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Sample records for experimental prosthetic graft

  1. [Localized purpura revealing vascular prosthetic graft infection].

    Science.gov (United States)

    Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

    2013-07-01

    Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  2. [Surgical management of limb prosthetic vascular graft exposure].

    Science.gov (United States)

    Wu, Hao; Wu, Wei-wei; Bai, Ming; Zeng, Rong; Song, Xiao-jun; Chen, Yu; Liu, Chang-wei

    2012-12-01

    To investigate the risk factors and surgical management of limb prosthetic vascular graft exposure. The clinical data of 17 patients suffering from limb prosthetic vascular graft exposure in Peking Union Medical College Hospital from August 2006 to December 2011 were retrospectively analyzed. Among 17 cases, 5 suffered from prosthetic vascular graft exposure after vascular bypass for the lower limb ischemia, whereas 12 were affected after the artificial graft arteriovenous fistula construction in the upper limbs for hemodialysis. The surgical procedures mainly included the local debridement as well as the local flap and transferred muscle-cutaneous flap reconstruction to preserve the prosthetic vascular graft. All 17 patients underwent local flap or muscle-cutaneous flap coverage procedure. After the surgery, the prosthetic vascular graft was successfully salvaged in 14 cases. The total successful rate was 82.4%. The surgery failed in three patients, in whom the prosthetic vascular grafts were finally removed. Local flap and transferred muscle-cutaneous flap reconstruction is an effective surgical management to salvage the exposed grafts.

  3. Prosthetic vascular graft infection and prosthetic joint infection caused byPseudomonas stutzeri.

    Science.gov (United States)

    Bonares, Michael J; Vaisman, Alon; Sharkawy, Abdu

    2016-01-01

    Pseudomonas stutzeri is infrequently isolated from clinical specimens, and if isolated, more likely represents colonization or contamination rather than infection. Despite this, there are dozens of case reports which describe clinically significant P. stutzeri infections at variable sites. A 69-year-old man had a P. stutzeri infection of a prosthetic vascular graft infection, which he received in Panama City. He was successfully treated with a single antipseudomonal agent for 6 weeks and the removal of the infected vascular graft. A 70-year-old man had a P. stutzeri infection of a prosthetic joint, which was successfully treated with a single anti-pseudomonal agent for 6 weeks. There is only one other documented case of a prosthetic vascular graft infection secondary to P. stutzeri . There are 5 documented cases of P. stutzeri prosthetic joint infections. The previous cases were treated with antibiotics and variably, source control with the removal of prosthetic material. Most cases of P. stutzeri infection are due to exposure in health care settings. Immunocompromised states such as HIV or hematological and solid tumor malignancies are risk factors for P. stutzeri infection. Infections caused by P. stutzeri are far less frequent and less fatal than those caused by P. aeruginosa. The etiology of a P. stutzeri infection could be exposure to soil and water, but also contaminated material in the health care setting or an immunocompromised state. Iatrogenic infections that are secondary to health care tourism are a potential cause of fever in the returned traveler.

  4. Exophiala (Wangiella dermatitidis Prosthetic Aortic Valve Endocarditis and Prosthetic Graft Infection in an Immune Competent Patient

    Directory of Open Access Journals (Sweden)

    Jay S. Berger

    2017-01-01

    Full Text Available Exophiala (Wangiella dermatitidis is an emerging dematiaceous fungus associated with high mortality rates and is a rare cause of endocarditis. We describe the first case of E. dermatitidis endocarditis of a prosthetic aortic valve and aortic graft in an immune competent patient with no clear risk factors of hematological acquisition.

  5. Prosthetic graft infection: limitations of indium white blood cell scanning

    International Nuclear Information System (INIS)

    Brunner, M.C.; Mitchell, R.S.; Baldwin, J.C.; James, D.R.; Olcott, C. IV; Mehigan, J.T.; McDougall, I.R.; Miller, D.C.

    1986-01-01

    The lack of a rapid, noninvasive, and accurate method to confirm or rule out prosthetic graft infection continues to constitute a compelling and vexing clinical problem. A host of adjunctive diagnostic techniques has been used in the past, but early promising results subsequently have usually not yielded acceptable sensitivity (reflecting false negatives) and specificity (reflecting false positive) data. White blood cell (WBC) indium 111 scanning has recently been added to this list. The utility and accuracy of 111 In WBC scans were assessed by retrospective review of WBC scan results in 70 patients undergoing evaluation for possible prosthetic graft infection over a 7-year period. Operative and autopsy data (mean follow-up, 18 months for survivors with negative scans) were used to confirm the 22 positive, 45 negative, and three equivocal WBC scans. The false positive rate (+/- 70% confidence limits) was 36% +/- 6% (n = 8) among the 22 patients with positive scans (44% +/- 6% [11 of 25] if the three equivocal scans are included as false positive), yielding a specificity of 85% +/- 5% and an overall accuracy rate of 88% +/- 4% (80% +/- 5% and 84% +/- 5%, respectively, if the three equivocal cases are considered as false positive). All three patients with equivocal scans ultimately were judged not to have prosthetic graft infection. As implied by the high accuracy rate, the sensitivity of the test was absolute (100% [14 of 14]); there were no false negative results

  6. In vitro adherence of bacteria to prosthetic grafting materials

    International Nuclear Information System (INIS)

    Brewer, A.R.; Stromberg, B.V.

    1990-01-01

    Adherence of bacteria to prosthetic grafting material is thought to play an important role in the ultimate development of prosthetic infections. To evaluate the role of bacterial adherence in the initiation and colonization of prosthetic materials, Proplast II, Gore-Tex, and silicone were evaluated for adherence of Escherichia coli and Staphylococcus aureus. Bacteria were radiolabeled and incubated with the study material. Adherence was determined by scintillation. Adherence to Proplast II and Gore-Tex reached a maximum at approximately 45 minutes of incubation and demonstrated a detachment phenomenon with E. coli. Similar results were noted with S. aureus, but with a maximal attachment at approximately 30 minutes. Interestingly, bacterial attachment to silicone continued to increase throughout the time of the incubation. In addition, adherence of S. aureus was at a faster rate than E. coli. Attachment of bacteria is a multifactorial process. However, the PTFE graft demonstrates a slower rate of attachment, lower total number of attached bacteria, and faster detachment. The importance of this phenomenon may help explain the foreign body effect of increased susceptibility to infection of foreign materials

  7. Remnant prosthetic graft in revision or limb-salvage surgery: routine complete excision?

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    Shenouda, Michael; Molena, Emma; Maftei, Nonica; Ali, Tahir

    2014-08-01

    Prosthetic graft occlusion following vascular reconstruction is a major cause of morbidity commonly necessitating further limb-salvage revascularization or life-saving amputation. It is therefore surprising that there is scant data in the literature regarding the optimal management of any remnant prosthetic grafts left in situ. We present a case series of 3 patients with remnant prosthetic graft infection following revisional arterial reconstruction for limb salvage and a literature review on this topic. Three patients presented to our institution with remnant prosthetic graft infection between March 2012 and January 2013. They had all undergone previous infrainguinal bypass surgery with polytetrafluorethylene (PTFE) grafts, which had subsequently thrombosed. Further limb salvage operations with autogenous long saphenous vein bypass in 2 cases and above-knee amputation in 1 case were performed. In all cases, the focus of infection was confirmed to have originated in the redundant remnant PTFE graft left in situ. These grafts were completely excised and the infected wounds were debrided. All patients made a full recovery. Remnant prosthetic grafts left in situ are shown in this series to be a proven nidus for infection. Published data indicate that these infection rates are greatest in revision vascular surgery and when performing amputations. We propose that routine excision of any occluded remnant prosthetic grafts in revision surgery be considered at the time of revascularization to mitigate against the risk of subsequent infection. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Diagnosis of arterial prosthetic graft infection by /sup 111/In oxine white blood cell scans

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, P.P.; Miller, D.C.; Jamieson, S.W.; Mitchell, R.S.; Reitz, B.A.; Olcott, C.; Mehigan, J.T.; Silberstein, R.J.; McDougall, I.R.

    1982-08-01

    Early and accurate diagnosis of infected prosthetic arterial grafts is difficult, despite the application of diverse diagnostic modalities. Delay in making the diagnosis is largely responsible for the high amputation and mortality rates associated with this complication. In nine patients with suspected graft infections, /sup 111/In white blood cell scanning was useful and accurate. Graft infection was proved in five cases and ruled out in three. One false-positive scan was due to a sigmoid diverticular abscess overlying the graft. /sup 111/In white blood cell scans may improve the accuracy of diagnosing infected prosthetic grafts, which may result in better limb and patient salvage rates.

  9. Diagnosis of arterial prosthetic graft infection by 111In oxine white blood cell scans

    International Nuclear Information System (INIS)

    McKeown, P.P.; Miller, D.C.; Jamieson, S.W.; Mitchell, R.S.; Reitz, B.A.; Olcott, C.; Mehigan, J.T.; Silberstein, R.J.; McDougall, I.R.

    1982-01-01

    Early and accurate diagnosis of infected prosthetic arterial grafts is difficult, despite the application of diverse diagnostic modalities. Delay in making the diagnosis is largely responsible for the high amputation and mortality rates associated with this complication. In nine patients with suspected graft infections, 111 In white blood cell scanning was useful and accurate. Graft infection was proved in five cases and ruled out in three. One false-positive scan was due to a sigmoid diverticular abscess overlying the graft. 111 In white blood cell scans may improve the accuracy of diagnosing infected prosthetic grafts, which may result in better limb and patient salvage rates

  10. 111 In-labeled leukocytes in the detection of prosthetic vascular graft infections

    International Nuclear Information System (INIS)

    Williamson, M.R.; Boyd, C.M.; Read, R.C.; Thompson, B.W.; Barnes, R.W.; Shah, H.R.; Balachandran, S.; Ferris, E.J.

    1986-01-01

    Making a clinical diagnosis of infection in prosthetic vascular grafts is difficult but when undiagnosed, this condition has a high mortality rate. Using Indium-111-labeled white-blood cells, 30 scans were performed in 21 patients suspected of having a prosthetic graft infection. The diagnosis of infected graft was confirmed by surgery in all cases, and lack of infection was established by resolution of symptoms with conservative therapy. Twenty-four hour scans of autologous Indium-111 leukocytes were obtained, and correlative CT studies were done in 11 cases. There were 13 infected grafts at surgery (purulent material present), and scans were positive in all (100% sensitivity); of 17 scans, there were 15 true negatives and two false positives (88% specificity). Using the criteria of gas or fluid around the graft, the sensitivity of CT was only 37% in a small subset of these patients. One-half of the cases in which infection was suspected clinically had no infection and had negative scans. Various types of grafts and graft materials were used, and there was no correlation with presence or absence of infection on the basis of the type of graft. Extragraft infection sites were found in five patients. In conclusion, use of Indium-111 leukocytes has been found to be an accurate and valuable diagnostic method for evaluation of suspected prosthetic vascular graft infection, and to have higher diagnostic accuracy than CT

  11. Prosthetic above-knee femoropopliteal bypass grafting: five-year results of a randomized trial.

    Science.gov (United States)

    Green, R M; Abbott, W M; Matsumoto, T; Wheeler, J R; Miller, N; Veith, F J; Money, S; Garrett, H E

    2000-03-01

    This trial was designed to identify factors affecting patency rates of primary prosthetic above-knee femoropopliteal bypass grafts at 5 years. A multi-institutional, prospective trial randomized 240 patients to compare patency rates of Gore-tex and Hemashield above-knee femoropopliteal bypass grafts at 5 years. Univariate comparisons of patency between levels of each prognostic variable were made with the Kaplan-Meier method. Variables that had a univariate P value less than.25 or those known to be important were submitted to a Cox regression analysis. The patient survival rate at 5 years was 59.4%. There were no differences in primary or secondary patency rates at 5 years between the two graft materials (primary, 45% vs 43% and secondary, 68% vs 68%). The risk for graft occlusion was significantly increased for patients younger than 65 years (2.1; P =.001) and for grafts with a diameter less than 7 mm (1.65; P =.0219). Variables with no apparent independent effect on patency rates were smoking status, runoff, diabetes mellitus, sex, presenting symptoms, and postoperative treatment with aspirin or Coumadin. Noninvasive test results were not predictive of subsequent graft function. Although the type of prosthetic used for above-knee femoropopliteal bypass grafts does not affect 5-year patency rates, age and graft size do influence results. These factors should be considered before a prosthetic bypass grafting procedure. Furthermore, these data should serve as a contemporary standard, with which evolving and conventional procedures can be compared.

  12. Repetitive complications after prosthetic graft for inflammatory aortic aneurysm

    Directory of Open Access Journals (Sweden)

    Yoshihiro Takeda

    2013-11-01

    Full Text Available The presence of retroperitoneal fibrosis after an aortic graft replacement is a marker of poor prognosis following aortic graft replacement. Herein we report the case of a 39-year-old man with retroperitoneal fibrosis that had been causing ureteral obstruction. The man had undergone repeated aortic graft replacement due to bacteremia and aortic graft–small intestinal fistula that occurred 4 years after initial aortic grafting for an inflammatory aortic aneurysm. The patient was discharged after 4 weeks of intravenous antibiotic therapy following the latest aortic graft replacement.

  13. Laparoscopic diagnosis and treatment of aortic vascular prosthetic graft infections in a porcine model

    DEFF Research Database (Denmark)

    Gao, Hongding; Lund, L; Prag, J

    2008-01-01

    To study the feasibility and efficacy of experimental laparoscopy in the diagnosis of aortic graft infection in pigs.......To study the feasibility and efficacy of experimental laparoscopy in the diagnosis of aortic graft infection in pigs....

  14. Brief report: biomarkers of aortic vascular prosthetic graft infection in a porcine model with Staphylococcus aureus

    DEFF Research Database (Denmark)

    Langerhuus, S. N.; Tønnesen, E. K.; Jensen, K. H.

    2010-01-01

    Aortic vascular prosthetic graft infection (AVPGI) with Staphylococcus aureus is a feared post-operative complication. This study was conducted to evaluate the clinical signs and potential biomarkers of infection in a porcine AVPGI model. The biomarkers evaluated were: C-reactive protein (CRP...

  15. Computerized tomographic evaluation of aortic prosthetic graft complications

    International Nuclear Information System (INIS)

    Kay, D.; Kalmar, J.A.

    1985-01-01

    Computerized tomography has been found to be an accurate and sensitive method of diagnosing complications of synthetic aortic grafts. Complications in this series of four cases included aortoesophageal fistula, aortoduodenal fistula, pseudoaneurysm, and retroperitoneal hematoma. 6 references, 5 figures

  16. Outcome of infrainguinal prosthetic graft infections depending on the surgical management.

    Science.gov (United States)

    Oberhuber, Alexander; Lohr, Bernard; Orend, Karl-Heinz; Schelzig, Hubert; Muehling, Bernd

    2014-10-01

    To evaluate the outcome of different therapeutic pathways to manage infrainguinal prosthetic graft infections. In this study a total of 66 patients treated between 1993 and 2009 (48 males and 18 females) were included. Subgroups were formed according to the following options of surgical management: excision of the grafts with or without arterial reconstruction (including prosthetic grafts and vein grafts), primary amputation, and surgical debridement with negative wound pressure therapy. Additionally, mortality, amputation rate, re-infection rate, and microbiological findings were analyzed. Mean age was 65.64±11.33 y and follow up was 22.21±36.85 mo. Thirty-day survival rate was 89.5%±4.1%, overall limb salvage rate was 82.5%±5.1%. In the group with primary amputation, one patient (20%) died; however, in the group of surgical debridement with negative wound pressure therapy, mortality was nil. In the group with graft excision, seven patients died (14.3%); no difference between the study groups was found (p=0.058). Amputation rate was 10% (n=5), 0% and 20.4% (n=10), respectively, with a higher rate in the primary amputation group (p<0.001). Reinfection rate was 0%, 8.3% (n=1) and 14.2% (n=7) respectively; p=0.822. Also, no difference was found regarding bypass level or revascularization graft material. Mortality and amputation rate is still high after infrainguinal prosthetic graft infection. Our strategy to preserve the graft whenever possible showed no difference compared with more aggressive strategies.

  17. Indium-111 leukocyte localization in infected prosthetic graft

    International Nuclear Information System (INIS)

    Purnell, G.L.; Walker, C.W.; Allison, J.W.; Dalrymple, G.V.

    1990-01-01

    Infective endocarditis can be difficult to prove, even in the face of strong clinical suspicion. A case in which standard methods of diagnosis failed to demonstrate endocarditis in a patient with recurrent Staphylococcus aureus bacteremia and porcine aortic valve is reported. An In-111 labelled leukocyte SPECT study demonstrated uptake in the aortic root and leaflets, and autopsy demonstrated vegetations on the leaflets. In-111 may prove useful in demonstrating endocarditis in patients with prosthetic valve infection

  18. Indium-111 leukocyte localization in infected prosthetic graft

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    Purnell, G.L.; Walker, C.W.; Allison, J.W.; Dalrymple, G.V. (Univ. of Arkansas for Medical Sciences, Little Rock (USA))

    1990-08-01

    Infective endocarditis can be difficult to prove, even in the face of strong clinical suspicion. A case in which standard methods of diagnosis failed to demonstrate endocarditis in a patient with recurrent Staphylococcus aureus bacteremia and porcine aortic valve is reported. An In-111 labelled leukocyte SPECT study demonstrated uptake in the aortic root and leaflets, and autopsy demonstrated vegetations on the leaflets. In-111 may prove useful in demonstrating endocarditis in patients with prosthetic valve infection.

  19. 18F-FDG uptake in noninfected prosthetic vascular grafts: incidence, patterns, and changes over time.

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    Keidar, Zohar; Pirmisashvili, Natalia; Leiderman, Max; Nitecki, Samy; Israel, Ora

    2014-03-01

    (18)F-FDG PET/CT is of value in the diagnosis of prosthetic vascular graft infection, but potential pitfalls related to tracer uptake in noninfected implants have been described. The current study assesses the incidence and patterns of (18)F-FDG uptake over time in noninfected grafts, in relationship to prosthetic material and location. A 12-y PET/CT database was retrospectively searched for cancer patients with prosthetic vascular grafts. Data retrieved from patient files included graft location, material, and time from surgery. Images were reviewed by 2 nuclear medicine physicians in consensus, with the presence and patterns (focal, diffuse homogeneous, inhomogeneous) of increased (18)F-FDG uptake in grafts recorded. The mean standardized uptake value in grafts (SUV-G) and mediastinum (SUV-M) was measured. The ratio of SUV-G to SUV-M (SUV-G/SUV-M) was calculated for each graft. One hundred seven prostheses were identified in 102 studies in 43 cancer patients. Sixty-seven prostheses were made of Dacron, 33 of Gore-Tex, and 7 were native veins. No increased (18)F-FDG uptake was found in 9 grafts (native veins, 4; Gore-Tex, 3; Dacron, 2). There was diffuse homogeneous uptake in 68 and inhomogeneous uptake in 30 grafts. The homogeneous pattern was more prevalent in Gore-Tex whereas the inhomogeneous uptake was seen more in Dacron vascular grafts. None of the grafts demonstrated focal uptake. The SUV-G range was 0.4-6.3 (average, 1.9), and SUV-M range was 0.6-2.4 (average, 1.4). The intensity of uptake was significantly higher in Dacron (SUV-G = 2.35 and SUV-G/SUV-M = 1.72) than in Gore-Tex (SUV-G = 1.09, SUV-G/SUV-M = 0.91) and native vein grafts (SUV-G = 1.07, SUV-G/SUV-M = 0.75) (P < 0.005). Native vein grafts showed a significant decrease in (18)F-FDG uptake over time whereas synthetic grafts showed no change in intensity for a follow-up of up to 16 y. Diffuse (18)F-FDG uptake was found in 92% of noninfected vascular prostheses, more in Dacron grafts than with

  20. Indium-111 platelet imaging for detection of platelet deposition in abdominal aneurysms and prosthetic arterial grafts

    International Nuclear Information System (INIS)

    Ritchie, J.L.; Stratton, J.R.; Thiele, B.; Haminton, G.W.; Warrick, L.N.; Huang, T.W.; Harker, L.A.

    1981-01-01

    Thirty-four platelet imaging studies were performed in 23 patients to determine whether platelet deposition could be detected in patients with vascular aneurysms (18 patients) or in patients in whom Dacron prosthetic grafts had been placed (5 patients). In patients in whom abnormal platelet deposition was detected, the effect of administration of platelet-active drugs on platelet deposition was examined. Of the 18 patients with an aneurysm, 12 had equivocally positive studies on initial imaging and 2 had equivocally positive images. Of five patients with Dacron arterial grafts in place, four had diffuse platelet deposition in the grafts; the fifth patient had a platelet deposition only in a pseudoaneurysm. Eight patients with an abdominal aneurysm and positive or equivocally positive baseline images were restudied during platelet-active drug therapy either with aspirin plus dipyridamole (seven patients) or with sulfinpyrazone (four patients). No patient studied during treatment with aspirin plus dipyridamole had detectably decreased platelet deposition compared with baseline determinations. In contrast, two of four patients studied while receiving sulfinpyrazone showed decreased platelet deposition. Thus, platelet imaging may be of value for studying platelet physiology in vivo and for assessing platelet-active drugs and the thrombogenicity of prosthetic graft materials in human beings

  1. Effects of cilostazol and k-134 on reconstructive surgery using prosthetic grafts in the abdominal aorta of beagle dogs.

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    Inoue, Yoshinori; Sugano, Norihide; Jibiki, Masatoshi; Kudo, Toshifumi; Iwai, Takehisa

    2008-01-01

    Problems associated with prosthetic graft replacement are stenosis at the anastomosis site and thrombus formation on the inner surface. Cilostazol is known to have antiplatelet activity and inhibit vascular smooth muscle cell proliferation and neointima thickening. A cilostazol derivative, (-)-6-[3-[3-cyclopropyl-3-[(1R,2R)-2-hydroxycyclohexyl]ureido]-propoxy]-2-(1H)-quinolinone (K-134), has more potent anti-platelet activity and anti-neointimal thickening activity than cilostazol in the in-vitro platelet aggregation and in-vivo anti-hyperplastic activity assay. The aim of this study was to investigate effects of cilostazol and K-134 on thrombus formation and neointimal thickening at the site of prosthetic graft replacement. Beagle dogs underwent infrarenal abdominal aortic resection with straight Dacron graft replacement, which were allocated to the control, cilostazol, and K-134 groups. Two dogs were dead without confirming the cause of death. After 6 months, all dogs were necropsied. All prosthetic grafts were patent in each group. Ratios of red thrombus to prosthetic graft area were 0.3+/-6.4%, and 3.3+/-4.5% in the cilostazol and K-134 groups, respectively, which were significant different from that in the control group (24.4+/-16.8%). However, no clear difference was seen among the 3 groups with respect to neointimal thickness (control group, 0.70+/-0.13 mm; cilostazol group, 0.59+/-0.14 mm; K-134 group, 0.67+/-0.14 mm). Cilostazol and K-134 significantly inhibited thrombus formation on the inner surface of the prosthetic graft at 6 months after graft replacement. Neointimal thickening on the inner surface was slight even in control-group animals, and the effects of cilostazol and K-134 on such thickening were unclear.

  2. The use of prosthetic grafts in complex military vascular trauma: a limb salvage strategy for patients with severely limited autologous conduit.

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    Vertrees, Amy; Fox, Charles J; Quan, Reagan W; Cox, Mitchell W; Adams, Eric D; Gillespie, David L

    2009-04-01

    The use of prosthetic grafts for reconstruction of military vascular trauma has been consistently discouraged. In the current conflict, however, the signature wound involves multiple extremities with significant loss of soft tissue and potential autogenous venous conduits. We reviewed the experience with the use of prosthetic grafts for the treatment of vascular injuries sustained during recent conflicts in Iraq and Afghanistan. Trauma registry records with combat-related vascular injuries repaired using prosthetic grafts were retrospectively reviewed from March 2003 to April 2006. Data collected included age, gender, mechanism of injury, vessel injured, conduit, graft patency, complications, including amputation and eventual outcome of repair. Prosthetic grafts were placed in 14 of 95 (15%) patients undergoing extremity bypass for vascular injuries. Patients were men with an average age of 25 years (range, 19-39 years). All prosthetic grafts in this series were made of polytetrafluoroethylene. Mechanism of injury included blast (n = 6), gunshot wounds (n = 6), and blunt trauma (n = 2), resulting in prosthetic repair of injuries to the superficial femoral (n = 8), brachial (n = 3), common carotid (n = 1), subclavian (n = 1), and axillary (n = 1) arteries. Mean evacuation time from injury to stateside arrival was 7 days (range, 3-9 days). Twelve grafts were placed initially at the time of injury, and two after vein graft blow out with secondary hemorrhage. The mean follow-up period was 427 days (range, 49-1,285 days). Seventy-nine percent of prosthetic grafts stayed patent in the short term, allowing patient stabilization, transport to a stateside facility, and elective revascularization with the remaining autologous vein graft. Three prosthetic grafts were replaced urgently for thrombosis. The remaining seven grafts were replaced electively for severe stenosis (3) or exposure (4) with presumed infection. There were no prosthetic graft blow outs or deaths in this

  3. Prosthetic aortic arch replacement. A new experimental technique.

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    Brodman, R F; Estner, S; Passik, C; Goldman, M

    1990-01-01

    An experimental method for rapid replacement of the transverse aortic arch is presented. Branched intraluminal prostheses were fashioned of varying sizes containing ascending and descending aortic limbs and branches for the brachiocephalic and subclavian vessels. Rigid rings were sewn into the ends to allow rapid fixation of the grafts using extraluminal ligatures. In 31 dogs, arch prostheses were inserted using inflow occlusion at normothermia. Twenty-seven animals successfully underwent aortic arch replacement during periods of circulatory arrest from 2.5 to 6.5 minutes. One animal was electively sacrificed 3 years after arch replacement. Various sized aortic arch prostheses manufactured for clinical use would have the potential advantages of technical simplicity of insertion and reduced cardiopulmonary bypass. Alternatively, varying sized tubular grafts for the brachiocephalic branches could be attached to the currently available tubular intraluminal grafts.

  4. Repeated transluminal endovascular Inoue stent graft placement for progressive dilatation of prosthetic graft that had been repaired with Inoue stent graft placement for dilatation 23 years after extraanatomical bypass.

    Science.gov (United States)

    Anzai, Tomohiro; Shimizu, Hideyuki; Yozu, Ryohei; Hashimoto, Subaru; Kuribayashi, Sachio; Inoue, Kanji

    2007-02-01

    A 76-year-old man had undergone aneurysm exclusion and ascending abdominal aortic extraanatomical bypass for a thoracoabdominal aortic aneurysm in 1978. In 1983 hemoptysis occurred, and resection and closure of the central stump of the aorta and a left lower lobectomy were performed. Dilatation (phi50 mm) of a prosthetic graft (Cooley Graft phi18 mm) used for extraanatomical bypass was noted in 2001 and was repaired by placement of an Inoue stent graft. However, the aneurysm diameter increased further (phi70 mm), although no endoleak was noted: Placement of an Inoue stent graft covering the whole length of the prosthetic graft was repeated in 2006. The postoperative course was smooth, no endoleak occurred, and the patient was discharged 2 weeks after surgery.

  5. Vascularized nerve grafts: an experimental study.

    Science.gov (United States)

    Donzelli, Renato; Capone, Crescenzo; Sgulò, Francesco Giovanni; Mariniello, Giuseppe; Maiuri, Francesco

    2016-08-01

    The aim of this study is to define an experimental model in order to promote the functional recovery of the nerves using grafts with vascular support (Vascular Nerve Grafts - VNG). The aim of this study is to define, on an experimental model in normal recipient bed, whether the functional recovery with VNG is superior to that obtained non-vascularized graft (NNG). Twenty male rabbits, which underwent dissection of sciatic nerve, were later treated by reinnervation through an autograft. In 10 animals the reconstruction of sciatic nerve was realized with VNG; in 10 control animals the reconstruction of sciatic nerve was realized with NNG. The VNG group showed a better axonal organization and a significantly higher number of regenerated axons in the early phases (after 30 days) than the NNG group, whereas the difference in the axonal number at day 90 was less significant; besides, the axon diameter and the myelin thickness were not significantly improved by VNG group. Our data suggests that the use of VNG leads to a faster regeneration process and a better functional recovery, although the final results are comparable to those of the NNG. VNG improve the quality of the axonal regeneration (axonal diameter and Schwann cells), although the increase in the axonal number is not significant and does not improve the long-term functional outcome.

  6. Initial in vitro and in vivo evaluation of a self-monitoring prosthetic bypass graft.

    Science.gov (United States)

    Neville, Richard F; Gupta, Samit K; Kuraguntla, David J

    2017-06-01

    Prosthetic grafts used for lower extremity revascularization and dialysis access fail because of hyperplastic stenosis and thrombosis. Graft surveillance is advocated to monitor function; however, graft failure can occur between episodic examinations. An innovative sensor with wireless, microchip technology allows automated surveillance with assessment of graft function using a "cloud"-based algorithm. We performed proof-of-concept experiments with in vitro and in vivo models to assess the feasibility such a real-time graft surveillance system. A self-monitoring graft system was evaluated consisting of a prosthetic conduit of expanded polytetrafluoroethylene and a sensor unit, and a microsensor, microelectronics, battery, and remote processor with a monitor. The sensor unit was integrated on the extraluminal surface of expanded polytetrafluoroethylene grafts without compromise to the lumen of the conduit. The grafts were tested in vitro in a pulsatile, recirculating flow system under physiologic flow parameters. The hemodynamic parameters were varied to assess the ability to obtain wireless signal acquisition reflecting real-time flow properties in vitro. Segments of custom tubing with reduced diameters were inserted into the model to mimic stenosis proximal and distal to the grafts. After characterization of the initial data, the self-monitoring grafts were implanted in an ovine carotid model to assess proof of concept in vivo with 30-day follow-up of signal acquisition as well as arteriographic and histologic analysis. In vitro flow data demonstrated the device was able to determine factors related to prosthetic graft function under varied hemodynamic flow conditions. Wireless signal acquisition using Bluetooth technology (Bluetooth SIG, Inc, Kirkland, Wash) allowed remote data analysis reflecting graft flow parameters through changes in microsensor voltage and frequency. Waveform analysis was applied to construct an algorithm using proprietary software and

  7. Effects of neurolytic concentrations of alcohol and phenol on Dacron and Gore-Tex vascular prosthetic grafts.

    Science.gov (United States)

    Gale, D W; Valley, M A; Rogers, J N; Poterack, K A

    1994-01-01

    Neurolytic nerve block, using either alcohol (A) or phenol (P), is frequently used to treat intractable pain. However, these agents may disrupt the integrity of prosthetic vascular grafts. To investigate this possibility, the tensile strength of Dacron (Meadox Medicals, Oakland, NJ) and Gore-Tex (W.L. Gore Associates, Flagstaff, AZ) vascular grafts was determined after in vitro exposure to various clinically used concentrations of A or P. Segments of Dacron and Gore-Tex graft were placed in the following solutions: saline (S), 6% and 9% P, and 25%, 50%, 75%, and 100% A, and stored at 23 degrees +/- 1 degree C for 72 hours. Axial maximum load (in kilonewtons, KN) and strain (in mm/mm) were determined with an Instron universal testing machine (Instron Corporation, Camden, MA). Samples from the S, 9% P, and the 100% A groups were evaluated using a scanning electron microscope. Dacron tensile strength decreased a maximum of 23% after exposure to 50%, 75%, and 100% A. Dacron strain capacity decreased after exposure to A (50%, 75%, 100%) and P (6%, 9%). Scanning electron microscope of both P and A showed significant degradation. No changes were found in the Gore-Tex group after exposure to P or A, however, scanning electron microscope of the 100% A sample showed moderate fiber degradation. The study shows that Dacron woven grafts are degraded by concentrations of A of at least 50%, and to a lesser extent, concentrations of at least 6%, while Gore-Tex had only minimal changes. While neurolytic block offers distinct advantages in patients with terminal cancer pain, the findings suggest that the use of more conservative modalities, such as oral medication regimens, be considered for the treatment of intractable pain in patients with vascular prosthetic grafts that are proximate to the proposed site of neurolysis.

  8. Use of rifampin-soaked gelatin-sealed polyester grafts for in situ treatment of primary aortic and vascular prosthetic infections.

    Science.gov (United States)

    Bandyk, D F; Novotney, M L; Johnson, B L; Back, M R; Roth, S R

    2001-01-01

    In situ treatment of artery/graft infection has distinct advantages compared to vessel excision and extra-anatomic bypass procedures. Based on animal studies of a rifampin-soaked, gelatin-impregnated polyester graft that demonstrated prolonged in vivo antibacterial activity, this antibiotic-bonded graft was used selectively in patients for in situ treatment of low-grade Gram-positive prosthetic graft infections or primary aortic infections not amenable to excision and ex situ bypass. In a 5-year period (1995-1999), 27 patients with prosthetic graft infection (aortofemoral, n = 18, femorofemoral, n = 3; axillofemoral, n = 1) or primary aortic infection (mycotic aneurysm, n = 3; infected AAA, n = 2) underwent excision of the infected vessel and in situ replacement with a rifampin soaked (45-60 mg/ml for 15 min) gelatin-impregnated polyester graft. All prosthetic graft infections were low grade in nature, caused Gram-positive bacteria (Staphylococcus epidermidis, 16; Staphylococcus aureus, 5; Streptococcus, 1), and were treated electively. Patients with mycotic aortic aneurysm presented with sepsis and underwent urgent or emergent surgery. Two (8%) patients died-1 as a result of a ruptured Salmonella mycotic aortic aneurysm and the other from methicillin-resistant S. aureus infection following deep vein replacement of an in situ replaced femorofemoral graft. No amputations or late deaths as the result of vascular infection occurred in the 25 surviving patients. Two patients developed recurrent infection caused by a rifampin-resistant S. epidermidis in a replaced aortofemoral graft limb and were successfully treated with graft excision and in situ autogenous vein replacement. Eighteen patients remain alive and clinically free of infection after a mean follow-up interval of 17 months. In situ replacement treatment using a rifampin-bonded prosthetic graft for low-grade staphylococcal arterial infection was safe, durable, and associated with eradication of clinical signs

  9. Comparison of graft patency, limb salvage, and antithrombotic therapy between prosthetic and autogenous below-knee bypass for critical limb ischemia.

    Science.gov (United States)

    Suckow, Bjoern D; Kraiss, Larry W; Stone, David H; Schanzer, Andres; Bertges, Daniel J; Baril, Donald T; Cronenwett, Jack L; Goodney, Philip P

    2013-11-01

    The autogenous vein is the preferred conduit in below-knee vascular reconstructions. However, many argue that prosthetic grafts can perform well in crural bypass with adjunctive antithrombotic therapy. We therefore compared outcomes of below-knee prosthetic versus autologous vein bypass grafts for critical limb ischemia and the use of adjunctive antithrombotic therapy in both settings. Utilizing the registry of the Vascular Study Group of New England (2003-2009), we studied 1227 patients who underwent below-knee bypass for critical limb ischemia, 223 of whom received a prosthetic graft to the below-knee popliteal artery (70%) or more distal target (30%). We used propensity matching to identify a patient cohort receiving single-segment saphenous vein yet had remained similar to the prosthetic cohort in terms of characteristics, graft origin/target, and antithrombotic regimen. Main outcome measures were graft patency and major limb amputation within 1 year. Secondary outcomes were bleeding complications (reoperation or transfusion) and mortality. We performed comparisons by conduit type and by antithrombotic therapy. Patients receiving prosthetic conduit were more likely to be treated with warfarin than those with greater saphenous vein (57% vs. 24%, Pprosthetic and single-segment saphenous vein grafts. In a subanalysis of grafts to tibial versus popliteal targets, we noted equivalent primary patency and amputation rates between prosthetic and venous conduits. Whereas overall 1-year prosthetic graft patency rates varied from 51% (aspirin+clopidogrel) to 78% (aspirin+warfarin), no significant differences were seen in primary patency or major amputation rates by antithrombotic therapy (P=0.32 and 0.17, respectively). Further, the incidence of bleeding complications and 1-year mortality did not differ by conduit type or antithrombotic regimen in the propensity-matched analysis. Although limited in size, our study demonstrates that, with appropriate patient selection and

  10. Coil embolization of a false aneurysm with aorto-cutaneous fistula after prosthetic graft replacement of the ascending aorta

    International Nuclear Information System (INIS)

    Miguel, Bruno; Camilleri, Lionel; Gabrillargues, Jean; Macheda, Bruno; Kubota, Hiroshi; Ravel, Anne; Riberolles, Charles de; Boyer, Louis

    2000-01-01

    Aim: To report palliative embolization of a false aneurysm over the distal suture line of an ascending aorta graft replacement. Material and Method: A 78-year-old male patient was admitted for increasing bleeding of a chronic Manubrium ulceration, 20 months after coronary artery bypass complicated by perioperative ascending aorta dissection requiring prosthetic graft replacement. One month later, he underwent epiploplasty for a mediastinitis followed by long-term antibiotic therapy. Five months later, he presented with a Manubrium ulceration of the sternotomy. Spiral computerized tomography (CT) and aortography revealed a 20 mm anterior peri-prosthetic false aneurysm with a wide neck. Advanced age, active mediastinitis and patient's objection led us to perform percutaneous occlusion according to the Moret remodeling technique while protecting the coils release with balloon catheter inflation. Results: No post-operative complication was observed and at 1-year follow-up the patient was doing well with no recurrent bleeding. Magnetic resonance imaging (MRI) and spiral CT controls confirmed coils stability without any internal flow. Conclusion: Percutaneous coils embolization of a large false aneurysm in the ascending aorta can be a palliative treatment in a surgically unsuited patient

  11. Risk factors and outcomes for nosocomial infection after prosthetic vascular grafts.

    Science.gov (United States)

    Fariñas, María Carmen; Campo, Ana; Duran, Raquel; Sarralde, José Aurelio; Nistal, Juan Francisco; Gutiérrez-Díez, José Francisco; Fariñas-Álvarez, Concepción

    2017-11-01

    The objective of this study was to determine risk factors for nosocomial infections (NIs) and predictors of mortality in patients with prosthetic vascular grafts (PVGs). This was a prospective cohort study of all consecutive patients who underwent PVG of the abdominal aorta with or without iliac-femoral involvement and peripheral PVG from April 2008 to August 2009 at a university hospital. Patients younger than 15 years and those with severe immunodeficiency were excluded. The follow-up period was until 3 years after surgery or until death. There were 261 patients included; 230 (88.12%) were male, and the mean age was 67.57 (standard deviation, 10.82) years. The reason for operation was aortic aneurysm in 49 (18.77%) patients or lower limb arteriopathy in 212 (81.23%) patients. NIs occurred in 71 (27.20%) patients. Of these, 42 were surgical site infections (SSIs), of which 61.9% occurred in the lower extremities (14 superficial, 10 deep, and 2 PVG infections) and 38.1% in the abdomen (7 superficial, 7 deep, and 2 PVG infections); 15 were respiratory tract infections; and 15 were urinary tract infections. Active lower extremity skin and soft tissue infection (SSTI) at the time of surgery was a significant predictor of NI for both types of PVG (abdominal aortic PVG: adjusted odds ratio [OR], 12.6; 95% confidence interval [CI], 1.15-138.19; peripheral PVG: adjusted OR, 2.43; 95% CI, 1.08-5.47). Other independent predictors of NI were mechanical ventilation (adjusted OR, 55.96; 95% CI, 3.9-802.39) for abdominal aortic PVG and low hemoglobin levels on admission (adjusted OR, 0.84; 95% CI, 0.71-0.99) and emergent surgery (adjusted OR, 4.39; 95% CI, 1.51-12.74) for peripheral PVG. The in-hospital mortality rate was 1.92%. The probability of surviving the first month was 0.96, and significant predictors of mortality were active lower extremity SSTI (adjusted risk ratio [RR], 12.07; 95% CI, 1.04-154.75), high postsurgical glucose levels (adjusted RR, 1.02; 95% CI, 1

  12. Less Than Total Excision of Infected Prosthetic PTFE Graft Does Not Increase the Risk of Reinfection.

    Science.gov (United States)

    Sgroi, Michael D; Kirkpatrick, Vincent E; Resnick, Karen A; Williams, Russell A; Wilson, Samuel E; Gordon, Ian L

    2015-01-01

    Traditional treatment of infected polytetrafluoroethylene (PTFE) grafts consist of removal of the entire prosthesis. Closure of the native vessels may compromise vascular patency. We examined the outcomes for patients in whom a PTFE remnant of an infected graft was retained on the vessel. We reviewed the operating room log from 2000 to 2011 and identified all patients who had partial removal of an infected PTFE graft used for hemodialysis or peripheral bypass. These patients were examined for subsequent complications. Twenty-seven patients underwent 30 partial graft excisions with mean follow-up of 27 months. A total of 17% (5 of 30) of the partial graft resection procedures resulted in complications. Of 48 total remnants left behind at the arterial or venous anastomoses, reinfection occurred in 15%. Leaving a well-incorporated small 1-to 5-mm PTFE remnant at the arterial or venous anastomoses can be performed safely with a low risk of complications. © The Author(s) 2015.

  13. A Case Report of Ridge Augmentation using Onlay Interpositional Graft: An Approach to Improve Prosthetic Prognosis of a Deficit Ridge

    Directory of Open Access Journals (Sweden)

    Devanand Shetty

    2014-01-01

    Full Text Available Background: Periodontal therapy has developed beyond the scope of the treatment of periodontal pathoses. Periodontal plastic surgery consists of the reconstructive procedures designed to enhance the both function and esthetics. Deficient ridges pose a severe problem to the restorative dentist in restoring the natural form, function and esthetics of the prosthesis replacing the natural dentition. Depending upon the severity, location of these defects and the prosthetic option chosen, hard and soft tissue ridge augmentation or non-surgical approach or a combination may help to address them. The present clinical report describes a soft tissue ridge augmentation of a localized ridge defect in maxillary aesthetic region using onlay interpositional graft followed by fixed partial denture.

  14. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    International Nuclear Information System (INIS)

    Kim, Charles Y.; Tandberg, Daniel J.; Rosenberg, Michael D.; Miller, Michael J.; Suhocki, Paul V.; Smith, Tony P.

    2012-01-01

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metal stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.

  15. Late prosthetic graft infection after frozen elephant trunk presenting by haemoptysis and positive ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography.

    Science.gov (United States)

    Morjan, Mohammed; Ali, Khaldoun; Harringer, Wolfgang; El-Essawi, Aschraf

    2014-11-01

    In cardiothoracic surgery, prosthetic graft infection represents a diagnostic and therapeutic challenge. Although clinical assessment, imaging techniques and microbiological investigations are helpful, late graft infection can be difficult to identify using classical diagnostic tools. An aggressive surgical approach involving removal and replacement of all prosthetic materials is technically demanding but remains the best strategy to eradicate infection. Herein, we report a case of a late aortic graft infection, after frozen elephant trunk implantation with atypical presentation, diagnosed with (18)F-fluorodeoxyglucose-positron emission tomography and treated successfully through a radical surgical strategy. This case emphasizes the emerging diagnostic role of positron emission tomography and encourages the adoption of an aggressive surgical approach. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  16. Sarpogrelate hydrochloride reduced intimal hyperplasia in experimental rabbit vein graft.

    Science.gov (United States)

    Kodama, Akio; Komori, Kimihiro; Hattori, Keisuke; Yamanouchi, Dai; Kajikuri, Junko; Itoh, Takeo

    2009-05-01

    The selective 5-HT(2A) receptor antagonist sarpogrelate has been clinically used for treatment in atherosclerotic diseases. However, it remains unknown whether administration of sarpogrelate inhibits intimal hyperplasia seen in autologous vein grafts. Therefore, we sought to clarify this question using an experimental rabbit vein graft model. Male rabbits were divided into two groups: a control group and a sarpogrelate-treated group. The jugular vein was interposed in the carotid artery in reversed fashion for 4 weeks and intimal hyperplasia of the grafted vein was measured (n = 8, in each group). Acetylcholine (ACh)-induced endothelium-dependent relaxation was tested by precontraction with prostaglandin F(2alpha) (PGF(2alpha), 5 muM) (n = 5, in each). endothelial nitric oxide synthase (eNOS) protein expression and superoxide production of these veins were also assessed. The suppression of intimal hyperplasia was significantly greater in the sarpogrelate-treated group than in the control group. ACh induced an endothelium-dependent relaxation in the sarpogrelate-treated group (but not in the control group). In endothelium-intact strips from the sarpogrelate-treated group, the nitric oxide (NO) synthase inhibitor nitroarginine enhanced the PGF(2alpha)-induced contraction and blocked the ACh-induced relaxation. Immunoreactive eNOS protein expression was similar between the two groups but superoxide production (estimated from ethidium fluorescence) in endothelial cells was significantly smaller in the sarpogrelate-treated group. The present results indicate that in vivo blockade of 5-HT(2A) receptors leads to an inhibition of intimal hyperplasia in rabbit vein graft. It is suggested that an increased function of endothelium-derived NO through a reduction in endothelial superoxide production may be a possible underlying mechanism for this. These novel findings support the clinical usefulness of sarpogrelate for preventing intimal hyperplasia in vein graft after bypass

  17. Efficacy of linezolid, teicoplanin, and vancomycin in prevention of an experimental polytetrafluoroethylene graft infection model caused by methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Mese, Bulent; Bozoglan, Orhan; Elveren, Serdal; Eroglu, Erdinc; Gul, Mustafa; Celik, Ahmet; Ciralik, Harun; Yildirimdemir, Halil Ibrahim; Yasim, Alptekin

    2015-03-27

    The aim of this study was to evaluate the effectiveness of linezolid, teicoplanin, and vancomycin in prevention of prosthetic vascular graft infections in a vascular graft infection model. Fifty rats were divided into 5 groups. A polytetrafluoroethylene graft was implanted on the back of each rat. Methicillin-resistant Staphylococcus aureus (MRSA) strain was inoculated into all rats except Group 1. Group 2 was not given any treatment, Group 3 received linezolid, Group 4 received vancomycin, and Group 5 received teicoplanin. The grafts were removed for microbiological and histological examinations on the 7th day. In addition, C-reactive protein and prealbumin levels and leukocyte counts in obtained blood specimens were determined. Group 1 did not have infection. Group 2 had bacteria 5.7 × 10(4) CFU/cm(2). Group 3 and Group 4 had less bacterial growth. Group 5 had no bacterial growth. The number of bacteria was significantly higher in Group 2 than in the other experimental groups and the control group (pprevention of prosthetic vascular graft infections.

  18. Experimental Validation of a Cardiac Simulator for in vitro Evaluation of Prosthetic Heart Valves

    Directory of Open Access Journals (Sweden)

    Ovandir Bazan

    Full Text Available Abstract Objective: This work describes the experimental validation of a cardiac simulator for three heart rates (60, 80 and 100 beats per minute, under physiological conditions, as a suitable environment for prosthetic heart valves testing in the mitral or aortic position. Methods: In the experiment, an aortic bileaflet mechanical valve and a mitral bioprosthesis were employed in the left ventricular model. A test fluid of 47.6% by volume of glycerin solution in water at 36.5ºC was used as blood analogue fluid. A supervisory control and data acquisition system implemented previously in LabVIEW was applied to induce the ventricular operation and to acquire the ventricular signals. The parameters of the left ventricular model operation were based on in vivo and in vitro data. The waves of ventricular and systemic pressures, aortic flow, stroke volume, among others, were acquired while manual adjustments in the arterial impedance model were also established. Results: The acquired waves showed good results concerning some in vivo data and requirements from the ISO 5840 standard. Conclusion: The experimental validation was performed, allowing, in future studies, characterizing the hydrodynamic performance of prosthetic heart valves.

  19. An experimental and theoretical framework for manufacturing prosthetic sockets for transtibial amputees.

    Science.gov (United States)

    Faustini, Mario C; Neptune, Richard R; Crawford, Richard H; Rogers, William E; Bosker, Gordon

    2006-09-01

    Selective laser sintering (SLS) is a powerful manufacturing technology that does not require part-specific tooling or significant human intervention and provides the ability to easily generate parts with complex geometric designs. The present work focuses on developing a manufacturing framework using this technology to produce subject-specific transtibial amputee prosthetic sockets made of Duraform PA, which is a nylon-based material. The framework includes establishing an overall socket design (using the patellar-tendon bearing approach), performing a structural analysis using the finite element method (FEM) to ensure structural reliability during patient use, and validating the results by comparing the model output with experimental data. The validation included quantifying the failure conditions for the socket through a series of bending moment and compression tests. In the case study performed, the FEM results were within 3% of the experimental failure loads for the socket and were considered satisfactory.

  20. An experimental study of exploitation of materials used for prosthetic temporary restorations

    Directory of Open Access Journals (Sweden)

    Szalewski Leszek

    2017-01-01

    Full Text Available Temporary restorations more often play their role for a definitely longer period of time, than the time necessary for implementation of final prosthetic work. Therefore, they are subjected to adverse effects of chemical, physical and thermal factors in a patient's oral cavity. Since loss of temporary prosthetic work can have negative consequences for an entire treatment process, it is important to identify a potential risk of damaging temporary restorations by factors derived from the diet of patients. The aim of this study was to evaluate the influence of components of the beverages, such as coffee and tea, consumed daily by the patients, on the mechanical properties of materials used in temporary restorations. The experimental design applied, as well as gained results, were justified by appropriate, chosen statistical methods. The conducted research demonstrated the change of mechanical properties of studied materials for their flexural strength, as well as microhardness. The tendency of changes in both result variables, compared with the samples kept in neutral environment – distilled water, indicates the decrease in mechanical strength and microhardness of materials conditioned in coffee and tea. It can be claimed that the components of beverages present in an everyday diet of patients have a considerably adverse effect on the quality of materials used for provisional crowns and bridges.

  1. [Experimental study of allogenic tendon with sheath grafting in chicken].

    Science.gov (United States)

    Zhang, Y L; Wang, S L; Gao, X S

    2001-03-01

    To investigate availability of deep freeze stored allogenic tendon with sheath grafting in repairing the tendon and sheath defect in the II area of flexor digitorum tendon. Sixty chickens with tendon and sheath defect were divided into 2 groups randomly, group A was treated with allogenic grafting and group B was treated with autogenic grafting, these two groups were divided into two subgroups respectively, they were, group A1 allogenic tendon with whole sheath grafting, group A2 allogenic tendon with partial sheath grafting, group B1 autogenic tendon with whole sheath grafting and group B2 autogenic tendon with whole sheath grafting. All the allogenic grafts were treated by deep freeze. Histomorphological study, histoimmunological study and slipping function of the grafts were measured after operation. In group A1 and B1, the local reaction was sever, the nutrition of tendon graft was barricaded by the whole sheath resulting in adhesion, degeneration and necrosis. In group A2 and B2, the tendon graft healed well and little adhesion existed between tendon and sheath. The results showed that there were significant differences between tendon grafting with whole sheath and tendon grafting with partial sheath. Deep freeze store can reduce the immunogenicity of allogenic tendon with sheath. Allogenic tendon with partial sheath grafting can be used as a new biological material for repairing the tendon and sheath defect.

  2. Limb Prosthetics

    Science.gov (United States)

    ... Catheter Insertion Additional Content Medical News Overview of Limb Prosthetics By James Baird, CPO, Director of Education, Hanger ... DOCTORS: Click here for the Professional Version Limb Prosthetics Overview of Limb Prosthetics Prosthetic Parts Options for Limb Prostheses Preparing ...

  3. Patient satisfaction after prosthetic rehabilitation of bone-grafted alveolar clefts with nonsubmerged ITI Straumann dental implants loaded at three months.

    Science.gov (United States)

    Landes, Constantin A; Bündgen, Lukas; Laudemann, Katharina; Ghanaati, Sharam; Sader, Robert

    2012-09-01

    To assess clinical, aesthetic, and quality-of-life parameters of cleft lip and palate patients' implant-supported crowns with ITI Straumann nonsubmerged and loaded after 3 months implants. In 17 bone-grafted cleft patients, 24 implants were placed nonsubmerged, loaded at 3 months to support crowns in the cleft area, and followed up at 40 months on average (± 22 months). The oral-health-related quality of life was assessed in all patients with the German Oral Health Impact Profile after implant therapy. Aesthetics were judged on photographs by dental professionals, nonprofessionals, and the patients themselves. The Implant Crown Aesthetic Index served as an objective tool. A total of 23 implants (95.8%) were loaded and in function. Clinical parameters were marginal bone loss of 1.15 ± 2.16 mm, peri-implant probing depth of 2.56 ± 0.66 mm, width of keratinized mucosa of 2.71 ± 1.1 mm, mucosal recession of 0.41 ± 0.8 mm, Periotest value of 0.18 ± 6.5, and German Oral Health Impact Profile summary score of ≤ 2. The best aesthetic outcome was assessed by the patients themselves. Soft tissues were rated worse than were implant-supported crowns. Implant-borne prosthetic rehabilitation of bone-grafted clefts with nonsubmerged ITI Straumann implants with 3 months' loading represents a reliable treatment option with high success rates in the long term. Functional aspects are comparable to those of noncleft patients. The oral-health-related quality of life of cleft patients is similar to that of noncleft patients. Aesthetics are restricted but satisfactory to patients and dental professionals. Aesthetics of peri-implant soft tissues should be improved in the future.

  4. Textural features of 18F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection

    International Nuclear Information System (INIS)

    Saleem, Ben R.; Zeebregts, Clark J.; Beukinga, Roelof J.; Slart, Riemer H.J.A.; Boellaard, Ronald; Glaudemans, Andor W.J.M.; Reijnen, Michel M.P.J.

    2017-01-01

    The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The objective of this retrospective study was to examine the feasibility and utility of 18 F-FDG uptake heterogeneity characterized by textural features to diagnose AGI. Thirty patients with a history of aortic graft reconstruction who underwent 18 F-FDG PET/CT scanning were included. Sixteen patients were suspected to have an AGI (group I). AGI was considered proven only in the case of a positive bacterial culture. Positive cultures were found in 10 of the 16 patients (group Ia), and in the other six patients, cultures remained negative (group Ib). A control group was formed of 14 patients undergoing 18 F-FDG PET for other reasons (group II). PET images were assessed using conventional maximal standardized uptake value (SUVmax), tissue-to-background ratio (TBR), and visual grading scale (VGS). Additionally, 64 different 18 F-FDG PET based textural features were applied to characterize 18 F-FDG uptake heterogeneity. To select candidate predictors, univariable logistic regression analysis was performed (α = 0.16). The accuracy was satisfactory in case of an AUC > 0.8. The feature selection process yielded the textural features named variance (AUC = 0.88), high grey level zone emphasis (AUC = 0.87), small zone low grey level emphasis (AUC = 0.80), and small zone high grey level emphasis (AUC = 0.81) most optimal for distinguishing between groups I and II. SUVmax, TBR, and VGS were also able to distinguish between these groups with AUCs of 0.87, 0.78, and 0.90, respectively. The textural feature named short run high grey level emphasis was able to distinguish group Ia from Ib (AUC = 0.83), while for the same task the TBR and VGS were not found to be predictive. SUVmax was found predictive in

  5. Textural features of {sup 18}F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection

    Energy Technology Data Exchange (ETDEWEB)

    Saleem, Ben R.; Zeebregts, Clark J. [University of Groningen, University Medical Center Groningen, Department of Surgery, Division of Vascular Surgery, P.O. Box 30 001, Groningen (Netherlands); Beukinga, Roelof J.; Slart, Riemer H.J.A. [University of Groningen, University Medical Center Groningen, Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University of Twente, Department of Biomedical Photonic Imaging (BMPI), Enschede (Netherlands); Boellaard, Ronald; Glaudemans, Andor W.J.M. [University of Groningen, University Medical Center Groningen, Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); Reijnen, Michel M.P.J. [Rijnstate Hospital, Department of Surgery, Arnhem (Netherlands)

    2017-05-15

    The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although {sup 18}F-fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The objective of this retrospective study was to examine the feasibility and utility of {sup 18}F-FDG uptake heterogeneity characterized by textural features to diagnose AGI. Thirty patients with a history of aortic graft reconstruction who underwent {sup 18}F-FDG PET/CT scanning were included. Sixteen patients were suspected to have an AGI (group I). AGI was considered proven only in the case of a positive bacterial culture. Positive cultures were found in 10 of the 16 patients (group Ia), and in the other six patients, cultures remained negative (group Ib). A control group was formed of 14 patients undergoing {sup 18}F-FDG PET for other reasons (group II). PET images were assessed using conventional maximal standardized uptake value (SUVmax), tissue-to-background ratio (TBR), and visual grading scale (VGS). Additionally, 64 different {sup 18}F-FDG PET based textural features were applied to characterize {sup 18}F-FDG uptake heterogeneity. To select candidate predictors, univariable logistic regression analysis was performed (α = 0.16). The accuracy was satisfactory in case of an AUC > 0.8. The feature selection process yielded the textural features named variance (AUC = 0.88), high grey level zone emphasis (AUC = 0.87), small zone low grey level emphasis (AUC = 0.80), and small zone high grey level emphasis (AUC = 0.81) most optimal for distinguishing between groups I and II. SUVmax, TBR, and VGS were also able to distinguish between these groups with AUCs of 0.87, 0.78, and 0.90, respectively. The textural feature named short run high grey level emphasis was able to distinguish group Ia from Ib (AUC = 0.83), while for the same task the TBR and VGS were not found to be predictive

  6. Scintigraphic follow up of autologous splenic grafts: An experimental and clinical study

    International Nuclear Information System (INIS)

    Reilmann, H.; Creutzig, H.; Pabst, R.; Kamran, D.

    1984-01-01

    The risk of overwhelming sepsis in splenectomized patients is well known and autotransplantation of splenic tissue might be considered as a prophylactic approach. Little is known, however, of the success of grafting in man. In six patients with autologous grafts after emergency splenectomy the ''trapping function'' (TF) was measured by sequential scintigraphy with heat damaged red cells every third month. To correlate TF with blood flow and histology, different experiments were done in pigs: ligation of the splenic artery or partial splenectomy or total splenectomy with grafting of fragments either subfascially or in the greater momentum. TF, blood flow with Rb-86 and immune response was measured at different times after surgery. Remnants left at the main vessels did not grow, while splenic tissue left at smaller vessels increased in size. There were great differences in blood flow per gram splenic tissue, but a significant correlation between TF and blood flow. All experimental grafts showed a normal function both of the white and the red pulp. In patients there was a growth of grafts in four, while in two no TF could be measured. TF is an indicator of relative blood flow to splenic grafts and therefore useful in the follow up of grafted patients

  7. Validation of a numerical 3-D fluid-structure interaction model for a prosthetic valve based on experimental PIV measurements.

    Science.gov (United States)

    Guivier-Curien, Carine; Deplano, Valérie; Bertrand, Eric

    2009-10-01

    A numerical 3-D fluid-structure interaction (FSI) model of a prosthetic aortic valve was developed, based on a commercial computational fluid dynamics (CFD) software program using an Arbitrary Eulerian Lagrangian (ALE) formulation. To make sure of the validity of this numerical model, an equivalent experimental model accounting for both the geometrical features and the hydrodynamic conditions was also developed. The leaflet and the flow behaviours around the bileaflet valve were investigated numerically and experimentally by performing particle image velocimetry (PIV) measurements. Through quantitative and qualitative comparisons, it was shown that the leaflet behaviour and the velocity fields were similar in both models. The present study allows the validation of a fully coupled 3-D FSI numerical model. The promising numerical tool could be therefore used to investigate clinical issues involving the aortic valve.

  8. The vascular pattern and viability of microvascularized rib grafts based on periosteal circulation--an experimental study

    International Nuclear Information System (INIS)

    Papanastasiou, V.W.; Lalonde, D.H.; Williams, H.B.

    1984-01-01

    Previous reports have stressed the importance of the nutrient blood supply in rib grafts transferred by microvascular anastomoses. In the present experimental study, we have demonstrated that a rib graft transferred by microvascular anastomoses based on periosteal vessels can survive; vascular clearing studies demonstrated that the vascularity of these grafts extends not only into the cortex but the medulla as well. The relative facility of harvesting these grafts (compared with those based on nutrient vessels) should make them the favored choice. Technetium bone scintigraphy proved accurate in the assessment of both vascular pattern and microanastomotic patency. Tetracycline labeling did not correlate well with the patency of a rib graft's pedicle blood supply

  9. Polyhydroxybutyrate/valerate/polycaprolactone small-diameter vascular graft: Experimental study of integration into organism

    Energy Technology Data Exchange (ETDEWEB)

    Antonova, L. V., E-mail: antonova.la@mail.ru; Burago, A. Yu.; Matveeva, V. G.; Velikanova, E. A.; Mukhamadiyarov, R. A.; Glushkova, T. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation); Mironov, A. V. [Kemerovo Cardiology Dispensary, Kemerovo (Russian Federation)

    2015-10-27

    We prepared polyhydroxybutyrate/valerate (PHBV)/polylcaprolactone (PCL) small-diameter vascular grafts using electrospinning. Surface structure was assessed by scanning electron microscopy whilst physicomechanical properties were investigated by longitudinal uniaxial tension testing. Patency of grafts implanted into the rat abdominal aorta was evaluated using a Doppler ultrasonography at 2 week, 1 month and 12 month postimplantation. In addition, we assessed local histological features, along with IL-1β, IL-2, IL-4, IL-10, TNFa, TGF-β1, and VEGF serum levels. We revealed that only 2 (25%) grafts were not thrombosed at 2 week and 1 month postimplantation. However, at 12 month postimplantation a satisfactory histological pattern was observed in 50% of all cases, and we detected a monolayer of endothelial cells on the inner graft surface in half the cases. Regarding other grafts, we revealed minor connective tissue hyperplasia in 41.7% of the grafts and an inflammatory infiltrate in the part of the arterial wall in 8.3% of the grafts. We found that the IL-1β serum level was 3.5-fold higher in the group of experimental rats at 12 month postimplantation (p < 0.01). In addition, the IL-2 and IL-4 serum levels at 12 month postimplantation were 2- and 2.8-fold higher as compared to short-term implantation (2 weeks and 1 month) and control rats (p < 0.05) whilst the IL-10 serum level at 1 and 12 month postimplantation was more than 100-fold higher in comparison with 2 week postimplantation and control rats (p < 0.001). Serum VEGF was detected only at 12 month postimplantation. All in all, we created a biocompatible PHBV/PCL small-diameter vascular graft with a high surface area to volume ratio. A long-term patency of biodegradable vascular grafts after implantation into the rat abdominal aorta and the absence of a considerable immune response confirmed a high biocompatibility of such construct and the possibility of its use as a vascular graft.

  10. Polyhydroxybutyrate/valerate/polycaprolactone small-diameter vascular graft: Experimental study of integration into organism

    Science.gov (United States)

    Antonova, L. V.; Burago, A. Yu.; Mironov, A. V.; Matveeva, V. G.; Velikanova, E. A.; Mukhamadiyarov, R. A.; Glushkova, T. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S.

    2015-10-01

    We prepared polyhydroxybutyrate/valerate (PHBV)/polylcaprolactone (PCL) small-diameter vascular grafts using electrospinning. Surface structure was assessed by scanning electron microscopy whilst physicomechanical properties were investigated by longitudinal uniaxial tension testing. Patency of grafts implanted into the rat abdominal aorta was evaluated using a Doppler ultrasonography at 2 week, 1 month and 12 month postimplantation. In addition, we assessed local histological features, along with IL-1β, IL-2, IL-4, IL-10, TNFa, TGF-β1, and VEGF serum levels. We revealed that only 2 (25%) grafts were not thrombosed at 2 week and 1 month postimplantation. However, at 12 month postimplantation a satisfactory histological pattern was observed in 50% of all cases, and we detected a monolayer of endothelial cells on the inner graft surface in half the cases. Regarding other grafts, we revealed minor connective tissue hyperplasia in 41.7% of the grafts and an inflammatory infiltrate in the part of the arterial wall in 8.3% of the grafts. We found that the IL-1β serum level was 3.5-fold higher in the group of experimental rats at 12 month postimplantation (p < 0.01). In addition, the IL-2 and IL-4 serum levels at 12 month postimplantation were 2- and 2.8-fold higher as compared to short-term implantation (2 weeks and 1 month) and control rats (p < 0.05) whilst the IL-10 serum level at 1 and 12 month postimplantation was more than 100-fold higher in comparison with 2 week postimplantation and control rats (p < 0.001). Serum VEGF was detected only at 12 month postimplantation. All in all, we created a biocompatible PHBV/PCL small-diameter vascular graft with a high surface area to volume ratio. A long-term patency of biodegradable vascular grafts after implantation into the rat abdominal aorta and the absence of a considerable immune response confirmed a high biocompatibility of such construct and the possibility of its use as a vascular graft.

  11. Cognitive vision system for control of dexterous prosthetic hands: Experimental evaluation

    Directory of Open Access Journals (Sweden)

    Došen Strahinja

    2010-08-01

    Full Text Available Abstract Background Dexterous prosthetic hands that were developed recently, such as SmartHand and i-LIMB, are highly sophisticated; they have individually controllable fingers and the thumb that is able to abduct/adduct. This flexibility allows implementation of many different grasping strategies, but also requires new control algorithms that can exploit the many degrees of freedom available. The current study presents and tests the operation of a new control method for dexterous prosthetic hands. Methods The central component of the proposed method is an autonomous controller comprising a vision system with rule-based reasoning mounted on a dexterous hand (CyberHand. The controller, termed cognitive vision system (CVS, mimics biological control and generates commands for prehension. The CVS was integrated into a hierarchical control structure: 1 the user triggers the system and controls the orientation of the hand; 2 a high-level controller automatically selects the grasp type and size; and 3 an embedded hand controller implements the selected grasp using closed-loop position/force control. The operation of the control system was tested in 13 healthy subjects who used Cyberhand, attached to the forearm, to grasp and transport 18 objects placed at two different distances. Results The system correctly estimated grasp type and size (nine commands in total in about 84% of the trials. In an additional 6% of the trials, the grasp type and/or size were different from the optimal ones, but they were still good enough for the grasp to be successful. If the control task was simplified by decreasing the number of possible commands, the classification accuracy increased (e.g., 93% for guessing the grasp type only. Conclusions The original outcome of this research is a novel controller empowered by vision and reasoning and capable of high-level analysis (i.e., determining object properties and autonomous decision making (i.e., selecting the grasp type and

  12. Prefabrication of a vascularized nerve graft by vessel implantation: preliminary report of an experimental model.

    Science.gov (United States)

    Cavadas, P C; Vera-Sempere, F J

    1994-01-01

    Regeneration through vascularized nerve grafts (VNG) seems to be better than nonvascularized nerve grafts (NVNG), especially in hostile beds. We report on an experimental technique of prefabrication of VNG by direct vessel implantation. An arteriovenous fistula was created in the groin region with autologous vein grafts in the Wistar rat model, and implanted into the sciatic nerve. Five weeks later the sciatic VNG was elevated on the prefabricated pedicle. The flap was free-transferred orthotopically over a silicone sheet to impede plasmatic imbibition. Flap viability at 3 days was complete. India ink injection of the AV fistula resulted in capillary ink filling within the nerve and surrounding tissues. Histologic sections of the flap were examined, revealing its neovascularity. In an ongoing study, the regeneration through this prefabricated VNG is being compared to native VNG.

  13. Oligothiol Graft-Copolymer Coatings Stabilize Gold Nanoparticles Against Harsh Experimental Conditions

    Science.gov (United States)

    Kang, Jun Sung; Taton, T. Andrew

    2013-01-01

    We report that poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) copolymers that bear multiple thiol groups on the polymer backbone are exceptional ligands for gold nanoparticles (AuNPs). In general, these graft copolymer ligands stabilize AuNPs against environments that would ordinarily lead to particle aggregation. To characterize the effect of copolymer structure on AuNP stability, we synthesized thiolated PLL-g-PEGs (PLL-g-[PEG:SH]) with different backbone lengths, PEG grafting densities, and number of thiols per polymer chain. AuNPs were then combined with these polymer ligands, and the stabilities of the resulting AuNP@PLL-g-[PEG:SH] particles against high temperature, oxidants, and competing thiol ligands were characterized using dynamic light scattering, visible absorption spectroscopy, and fluorescence spectrophotometry. Our observations indicate that thiolated PLL-g-PEG ligands combine thermodynamic stabilization via multiple Au-S bonds and steric stabilization by PEG grafts, and the best graft copolymer ligands balance these two effects. We hope that this new ligand system enables AuNPs to be applied to biotechnological applications that require harsh experimental conditions. PMID:22957513

  14. Graft infections after surgical aortic reconstructions

    NARCIS (Netherlands)

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open

  15. Socket grafting with the use of autologous bone: an experimental study in the dog.

    Science.gov (United States)

    Araújo, Mauricio G; Lindhe, Jan

    2011-01-01

    studies in humans and animals have shown that following tooth removal (loss), the alveolar ridge becomes markedly reduced. Attempts made to counteract such ridge diminution by installing implants in the fresh extraction sockets were not successful, while socket grafting with anorganic bovine bone mineral prevented ridge contraction. to examine whether grafting of the alveolar socket with the use of chips of autologous bone may allow ridge preservation following tooth extraction. in five beagle dogs, the distal roots of the third and fourth mandibular premolars were removed. The sockets in the right or the left jaw quadrant were grafted with either anorganic bovine bone or with chips of autologous bone harvested from the buccal bone plate. After 3 months of healing, biopsies of the experimental sites were sampled, prepared for buccal-lingual ground sections and examined with respect to size and composition. it was observed that the majority of the autologous bone chips during healing had been resorbed and that the graft apparently did not interfere with socket healing or processes that resulted in ridge resorption. autologous bone chips placed in the fresh extraction socket will (i) neither stimulate nor retard new bone formation and (ii) not prevent ridge resorption that occurs during healing following tooth extraction.

  16. Experimental Comparison of Cranial Particulate Bone Graft, rhBMP-2, and Split Cranial Bone Graft for Inlay Cranioplasty.

    Science.gov (United States)

    Hassanein, Aladdin H; Couto, Rafael A; Kurek, Kyle C; Rogers, Gary F; Mulliken, John B; Greene, Arin K

    2013-05-01

    Background :  Particulate bone graft and recombinant human bone morphogenetic protein-2 (rhBMP-2) are options for inlay cranioplasty in children who have not developed a diploic space. The purpose of this study was to determine whether particulate bone graft or rhBMP-2 has superior efficacy for inlay cranioplasty and to compare these substances to split cranial bone. Methods :  A 17 mm × 17 mm critical-sized defect was made in the parietal bones of 22 rabbits and managed in four ways: Group I (no implant; n=5), Group II (particulate bone graft; n=5), Group III (rhBMP-2; n=7), and Group IV (split cranial bone graft; n=5). Animals underwent microcomputed tomography and histologic analysis 16 weeks after cranioplasty. Results :  Defects without an implant (Group I) demonstrated inferior ossification (41.4%; interquartile range [IQR], 28.9% to 42.5%) compared to those treated with particulate bone graft (Group II: 99.5%; IQR, 97.8% to 100%), rhBMP-2 (Group III: 99.6%; IQR, 99.5% to 100%), or split cranial bone (Group IV: 100%) (P inlay calvarial defect areas equally, although the thickness of bone healed with rhBMP-2 is inferior. Clinically, particulate bone graft or split cranial bone graft may be superior to rhBMP-2 for inlay cranioplasty.

  17. Concepts to optimize stent-grafting of abdominal aortic aneurysms based on results of experimental studies

    International Nuclear Information System (INIS)

    Chavan, A.; Kirchhoff, T.; Baus, S.; Galanski, M.; Pichlmaier, M.

    2001-01-01

    Purpose. In the endoluminal therapy of abdominal aortic aneurysms, a short proximal aneurysm neck, endoleaks and the large size and stiffness of the introducer systems are responsible for many of the complications and sub-optimal outcomes. The purpose of the present review article is to to suggest strategies to minimize these complications based on the results of experimental studies in animals. Material and methods. After implanting various types of stents across the renal artery origins, the functional and morphological changes in the kidneys and renal vessels were studied by various authors. In order to prevent progressive widening of the proximal aneurysmal neck and graft dislocation, Sonesson et al. performed a laparoscopic banding around the proximal neck in pigs. To study the effects of endoleaks, Marty, Schurink and Pitton carried out pressure measurements in experimental aneurysms with and without endoleaks. Sakaguchi and Pavcnik developed the 'Twin-tube endografts' (TTEG) and the 'Bifurcated drum occluder endografts' (BDOEG) and tested them in dogs. Results. Up to 3 months after suprarenal stent placement, Chavan et al. detected no significant fall in the mean inulin clearance in sheep (140±46 ml/min before, 137±58 ml/min after). Nasim et al. and Malina et al. reported similar observations with respect to renal function. Suprarenal fixation may result in isolated thrombotic occlusions of the renal arteries and microinfarcts in the kidneys. Mean aortic diameters at the level of banding were significantly smaller in the animals with aortic banding as opposed to those in the control group without banding (8 mm vs 11 mm, p=0.004). The banding caused a secure proximal fixation of the stent-graft. Persistent endoleaks resulted in significantly higher intraaneurysmal pressures. Although the TTEG and the BDOEG stent-grafts required smaller sheaths, occlusions were observed in 8% (TTEG) and 60% (BDOEG) of the graft limbs. (orig.) [de

  18. Use of human fat grafting in the prevention of perineural adherence: Experimental study in athymic mouse.

    Directory of Open Access Journals (Sweden)

    Mario Cherubino

    Full Text Available Perineural adherences represent a problem after surgery involving peripheral neural system. Fat-grafting with adipose derived stem cells (ASCs with their pro-regenerative characteristics can be important to prevent the neural damage or to facilitate the neural regeneration. Our idea was to use the fat-grafting as an anti-adherence device and test its efficacy on a postsurgical scar animal model and comparing to an antiadhesive gel. 32 athymic mice were operated under magnification, we exposed both sciatic nerves. We randomly divided all sciatic nerves into four experimental groups: burning (1, burning + carboxy-methylcellulose and poly- ethylene oxide (CMC-PEO (2 + human adipose fat tissue (3, control group (4. Bio-mechanical evaluation was performed to measure the peak force required to pull out the nerve from the muscular bed.in the CMC-PEO group the peak pull out force was 0.37 Newton. In the fat grafted group we registered a peak pull out force of 0.35 N (t Student 0.913. In burning group the force necessary to tear the nerve apart was markedly superior (0.46 N. In control group, we reported the minimal strength (0.31 N to slide the nerve from the tissue. Histologically, in the group treated with fat-grating, a thinner scar layer was highlighted. Considering the results of this study we can support the efficacy in animal experimental model of fat graft as an anti-adherence device in peripheral nerve surgery.

  19. [Deformations of acetabulum with load before and after prosthetic implantation. An experimental study by extensometry].

    Science.gov (United States)

    Massin, P; Landjerit, B; Roy-Camille, R; Thourot, M; Jacquard-Simon, N

    1993-01-01

    Using fresh cadavers pelves, an experimental model of unipodal stance was performed. The skeleton (femurs, pelvis and 2 lumbar vertebrae) was connected to the machine by non constrained junctions. Muscles (gluteus, iliacus and rectus abdominis) were simulated. Using this model, monopodal stance could be maintained under load. Strain measurements were performed on the periphery of the acetabulum. Results showed that periacetabular strains were dependent on the mobility of the lower lumbar intervertebral discs as well as on the type equilibrium (uni or bipodal). It was remarkable that the blockage of intervertebral rotations (experimental lombo-sacral arthrodesis) increased acetabular stiffness. The influence of total hip replacement was also studied. Periacetabular strains remained important around cementless press-fit cups. This would plead for a non weight bearing postoperative period in clinical practice of cementless arthroplasty. Important deformations also persisted around conventional cemented cups, justifying further research to limit periacetabular deformations around total hip prostheses, in the hope of limiting the rate of late acetabular loosening.

  20. Experimental studies in chickens on the initial nutrition of tendon grafts.

    Science.gov (United States)

    Manske, P R; Lesker, P A; Bridwell, K

    1979-11-01

    A study of nutrition of various tendon graft preparations in adult chickens (up to 2 weeks after grafting), using tritiated proline and a trichloracetic acid extraction technique which separated the free and metabolized amino acid fractions, suggests that diffusion of nutrients is an important process in the initial nutrition of tendon grafts, that tendon grafts are metabolically active and viable structures, that adhesions which are frequently associated with tendon grafts do not appear to be essential to the nutrition of grafts, and that tendon grafts within fibrous pseudosheaths are nourished as effectively as grafts within synovial sheaths.

  1. Effect of polyethylene glycol-based preservation solutions on graft injury in experimental kidney transplantation.

    Science.gov (United States)

    Thuillier, R; Renard, C; Rogel-Gaillard, C; Demars, J; Milan, D; Forestier, L; Ouldmoulene, A; Goujon, J M; Badet, L; Hauet, T

    2011-03-01

    New preservation solutions are emerging, of various ionic compositions and with hydroxyethyl starch replaced by polymers such as polyethylene glycols (PEGs), offering the potential for 'immunocamouflage'. This experimental study investigated which of three clinically available preservation protocols offered the best graft protection, based on epithelial-to-mesenchymal transition (EMT) and fibrosis. Kidneys were preserved for 24 h at 4° C with University of Wisconsin solution (UW)as standard, compared with solutions containing either 1 g/l PEG 35 kDa (Institute Georges Lopez solution, IGL) or 30 g/l PEG 20 kDa (solution de conservation des organes et des tissus, SCOT). Animals were followed for up to 3 months and development of EMT, tubular atrophy and fibrosis was evaluated in comparison with sham-operated animals. Functional recovery was better in the SCOT group compared with the other groups. Chronic fibrosis, EMT and inflammation were observed in the UW and IGL groups, but limited in the SCOT group. Levels of profibrosis markers such as transforming growth factor β1, plasminogen activator inhibitor 1 and connective tissue growth factor were increased in IGL and UW groups compared with the SCOT group. Hypoxia-inducible factor (HIF) 1α and 2α expression was increased at 3 months in grafts preserved in UW and IGL, but detected transiently on day 14 when SCOT was used. Expression of HIF-regulated genes vascular endothelial growth factor and erythropoietin was increased in UW and IGL groups. The choice of colloid and ionic content is paramount in providing long-term protection against chronic graft injury after renal transplantation. Preservation solutions based on PEGs may optimize graft quality.

  2. Grafted natural polymer as new drag reducing agent: An experimental approach

    Directory of Open Access Journals (Sweden)

    Abdulbari Hayder A.

    2012-01-01

    Full Text Available The present investigation introduces a new natural drag reducing agent which has the ability to improve the flow in pipelines carrying aqueous or hydrocarbon liquids in turbulent flow. Okra (Abelmoschus esculentus mucilage drag reduction performance was tested in water and hydrocarbon (gas-oil media after grafting. The drag reduction test was conducted in a buildup closed loop liquid circulation system consists of two pipes 0.0127 and 0.0381 m Inside Diameter (ID, four testing sections in each pipe (0.5 to 2.0 m, tank, pump and pressure transmitters. Reynolds number (Re, additive concentration and the transported media type (water and gas-oil, were the major drag reduction variables investigated. The experimental results show that, new additive drag reduction ability is high with maximum percentage of drag reduction (%Dr up to 60% was achieved. The experimental results showed that the drag reduction ability increased by increasing the additive concentration. The %Dr was found to increase by increasing the Re by using the water-soluble additive while it was found to decrease by increasing the Re when using the oil-soluble additive. The %Dr was higher in the 0.0381 m ID pipe. Finally, the grafted and natural mucilage showed high resistance to shear forces when circulated continuously for 200 seconds in the closed-loop system.

  3. Long-Term Outcomes of Catheter-Directed Thrombolysis for Acute Lower Extremity Occlusions of Native Arteries and Prosthetic Bypass Grafts

    NARCIS (Netherlands)

    Schrijver, A. Marjolein; de Vries, Jean Paul P M; van den Heuvel, Daniel A F; Moll, Frans L.

    2016-01-01

    Background Catheter-directed thrombolysis is a well-accepted treatment for acute lower extremity occlusions of native arteries and bypass grafts. Several variables that affect outcomes of thrombolysis have been identified. The hypothesis of this study was that the long-term outcome after

  4. Experimental substantiation of the design of a prosthetic heart valve for «valve-in-valve» implantation

    Directory of Open Access Journals (Sweden)

    K. Yu. Klyshnikov

    2017-01-01

    Full Text Available The aim of the study was to perform a series of in vitro tests of a prototype of the developing heart valve prosthesis to evaluate its functional characteristics. Materials and methods. In this work we have used the frames and full prototypes of the prosthesis, consisting of a stent-like stainless steel support frame with mounted biological leaflets and cover. The authors evaluated the calculated and experimental forces necessary for the displacement of the sutureless implanted prosthesis using the test machine under uniaxial tension. The risk of defects and damages to the supporting framework as a result of implantation was evaluated by scanning electron microscopy. The hydrodynamic characteristics of the prosthesis were investigated under physiological conditions and «valvein-valve» implantation. Evaluation of the ergonomics and applicability of the proposed construction on the cadaver heart model of cattle was carried out. Results. As a result of the forces assessment, it was found that the force required to shear the prosthesis was 3.12 ± 0.37 N, while the calculated value was 1.7 N, which is significantly lower than the obtained value. The comparison of the images obtained with small and large magnifications demonstrated the absence of critical surface defects. Additional analysis under the super-large magnifications also did not reveal problem areas. During the hydrodynamic study, it was shown that the average transplant gradient increased slightly from 2.8–3.4 to 3.2–4.5 mm Hg for the initial prosthesis and the «valve-in-valve» complex, respectively. The decrease of the effective orifice area was 6–9% relative to the initial one. Evaluation of the implantation technique demonstrated the consistency of the approach: the use of the developed holder in combination with the balloon implantation system made it possible to position the prosthesis throughout the procedure. Conclusion. The series of tests demonstrates the consistency

  5. The effect of butyric acid with autogenous omental graft on healing of experimental Achilles tendon injury in rabbits.

    Science.gov (United States)

    Jahani, S; Moslemi, H R; Dehghan, M M; Sedaghat, R; Mazaheri Nezhad, R; Rezaee Moghaddam, D

    2015-01-01

    In this study, the role of local injection of butyric acid (BA) with autogenous omental graft was evaluated in healing of experimental Achilles tendon injury in rabbits. Nine adult male New Zealand rabbits were anesthetized and a partial thickness tenotomy was created on both hindlimbs. In treated group, omental graft was secured in place using BA soaked polygalactin 910 suture. In control group, the graft was sutured without BA. Butyric acid and normal saline were injected daily to treatment and control groups for three days, respectively. Based on the findings, on day 15 after injury, the tendon sections showed that healing rate in BA treated group was higher than that in control group. Furthermore, at days 28 and 45, comparison between BA treated and control groups demonstrated that BA increased the healing rate but with no significance. In summary, results of this study show that application of BA with autogenous omental graft can improve healing process of damaged Achilles tendon.

  6. Experimental Study of Real-Time Classification of 17 Voluntary Movements for Multi-Degree Myoelectric Prosthetic Hand

    Directory of Open Access Journals (Sweden)

    Trongmun Jiralerspong

    2017-11-01

    Full Text Available The myoelectric prosthetic hand is a powerful tool developed to help people with upper limb loss restore the functions of a biological hand. Recognizing multiple hand motions from only a few electromyography (EMG sensors is one of the requirements for the development of prosthetic hands with high level of usability. This task is highly challenging because both classification rate and misclassification rate worsen with additional hand motions. This paper presents a signal processing technique that uses spectral features and an artificial neural network to classify 17 voluntary movements from EMG signals. The main highlight will be on the use of a small set of low-cost EMG sensor for classification of a reasonably large number of hand movements. The aim of this work is to extend the capabilities to recognize and produce multiple movements beyond what is currently feasible. This work will also show and discuss about how tailoring the number of hand motions for a specific task can help develop a more reliable prosthetic hand system. Online classification experiments have been conducted on seven male and five female participants to evaluate the validity of the proposed method. The proposed algorithm achieves an overall correct classification rate of up to 83%, thus, demonstrating the potential to classify 17 movements from 6 EMG sensors. Furthermore, classifying 9 motions using this method could achieve an accuracy of up to 92%. These results show that if the prosthetic hand is intended for a specific task, limiting the number of motions can significantly increase the performance and usability.

  7. Ceacam1 separates graft-versus-host-disease from graft-versus-tumor activity after experimental allogeneic bone marrow transplantation.

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    Sydney X Lu

    Full Text Available Allogeneic bone marrow transplantation (allo-BMT is a potentially curative therapy for a variety of hematologic diseases, but benefits, including graft-versus-tumor (GVT activity are limited by graft-versus-host-disease (GVHD. Carcinoembryonic antigen related cell adhesion molecule 1 (Ceacam1 is a transmembrane glycoprotein found on epithelium, T cells, and many tumors. It regulates a variety of physiologic and pathological processes such as tumor biology, leukocyte activation, and energy homeostasis. Previous studies suggest that Ceacam1 negatively regulates inflammation in inflammatory bowel disease models.We studied Ceacam1 as a regulator of GVHD and GVT after allogeneic bone marrow transplantation (allo-BMT in mouse models. In vivo, Ceacam1(-/- T cells caused increased GVHD mortality and GVHD of the colon, and greater numbers of donor T cells were positive for activation markers (CD25(hi, CD62L(lo. Additionally, Ceacam1(-/- CD8 T cells had greater expression of the gut-trafficking integrin α(4β(7, though both CD4 and CD8 T cells were found increased numbers in the gut post-transplant. Ceacam1(-/- recipients also experienced increased GVHD mortality and GVHD of the colon, and alloreactive T cells displayed increased activation. Additionally, Ceacam1(-/- mice had increased mortality and decreased numbers of regenerating small intestinal crypts upon radiation exposure. Conversely, Ceacam1-overexpressing T cells caused attenuated target-organ and systemic GVHD, which correlated with decreased donor T cell numbers in target tissues, and mortality. Finally, graft-versus-tumor survival in a Ceacam1(+ lymphoma model was improved in animals receiving Ceacam1(-/- vs. control T cells.We conclude that Ceacam1 regulates T cell activation, GVHD target organ damage, and numbers of donor T cells in lymphoid organs and GVHD target tissues. In recipients of allo-BMT, Ceacam1 may also regulate tissue radiosensitivity. Because of its expression on both the

  8. Graft infections after surgical aortic reconstructions

    OpenAIRE

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open surgical reconstructions as first line of treatment for aorto-iliac diseases. Nowadays, open reconstructions are primarily reserved for patients unsuitable for endovascular reconstructions or for redo ...

  9. That hemodynamics and not material mismatch is of primary concern in bypass graft failure: an experimental argument.

    Science.gov (United States)

    O'Brien, Thomas; Morris, Liam; Walsh, Michael; McGloughlin, Tim

    2005-10-01

    The long term patency of end-to-side peripheral artery bypasses are low due to failure of the graft generally at the distal end of the bypass. Both material mismatch between the graft and the host artery and junction hemodynamics are cited as being major factors in disease formation at the junction. This study uses experimental methods to investigate the major differences in fluid dynamics and wall mechanics at the proximal and distal ends for rigid and compliant bypass grafts. Injection moulding was used to produce idealized transparent and compliant models of the graft/ artery junction configuration. An ePTFE graft was then used to stiffen one of the models. These models were then investigated using two-dimensional video extensometry and one-dimensional laser Doppler anemometry to determine the junction deformations and fluid velocity profiles for the rigid and complaint graft anastomotic junctions. Junction strains were evaluated and generally found to be under 5% with a peak stain measured in the stiff graft model junction of 8.3% at 100 mmHg applied pressure. Hemodynamic results were found to yield up to 40% difference in fluid velocities for the stiff/compliant comparison but up to 80% for the proximal/distal end comparisons. Similar strain conditions were assumed for the proximal and distal models while significant differences were noted in their associated hemodynamic changes. In contrasting the fluid dynamics and wall mechanics for the proximal and distal anastomoses, it is evident from the results of this study, that junction hemodynamics are the more variable factor.

  10. Biphasic alloplastic graft used to preserve the dimension of the edentulous ridge: an experimental study in the dog.

    Science.gov (United States)

    Lindhe, J; Araújo, M G; Bufler, M; Liljenberg, B

    2013-10-01

    Loss of teeth results in marked qualitative and quantitative alterations of the alveolar process at the edentulous site. It was observed that a graft comprised of bovine bone mineral placed in the fresh extraction socket delayed tissue modeling, but preserved the dimension of the ridge at edentulous sites. To analyze the influence of a biphasic synthetic graft on tissue modeling and remodeling during healing of extraction wounds. Five beagle dogs were used. Two premolars in the maxilla and two in the mandible were included. Full thickness flaps were elevated and the distal roots were removed. An alloplastic graft (BPCAP; α-TCP core coated with nanocrystalline biomimetic hydroxyapatite) embedded in porcine collagen was placed to fill the fresh extraction socket of the premolar sites. Flaps were replaced to cover the entrance of the extraction sockets during early healing. The extraction and grafting procedures were scheduled to allow for the study of 1, 2, and 3 months socket healing. The biopsies from the maxillary sites were decalcified, embedded in paraffin, and stained to allow the study of various aspects of hard tissue formation. The biopsies from the mandibular sites were processed for ground sectioning and used to evaluate alterations of ridge dimensions after 3 months of socket healing. It was documented that the biphasic alloplastic graft did not undergo marked resorption during tissue modeling and remodeling, but allowed large amounts of bone to form within the post-extraction site. Grafting the experimental sites with this biomaterial furthermore counteracted ridge resorption that otherwise occurs following tooth extraction. © 2012 John Wiley & Sons A/S.

  11. Repair of bile duct injuries with Gore-Tex vascular grafts: experimental study in dogs.

    Science.gov (United States)

    Gómez, Néstor A; Alvarez, Ludwig R; Mite, Alfredo; Andrade, Jean P; Alvarez, José R; Vargas, Paola E; Tomalá, Nancy E; Vivas, Alex F; Zapatier, Jorge A

    2002-01-01

    Bile duct injury is the most feared complication related to biliary tract operations. The goal of this investigation was to offer an alternative treatment that might prevent this complication. Twelve mongrel dogs, thin-walled FEP-ringed Gore-Tex vascular grafts, and Gore-Tex sutures were used in this study. The dogs were randomized into three groups of four according to the length of time of graft implantation: group 1 = 1 month; group 2 = 2 months; and group 3 = 3 months. During the first part of the study, a biliary injury was induced by ligating the middle choledocus after performing a conventional cholecystectomy. During the second part of the study, biliodigestive and biliobiliary anastomosis were performed using Gore-Tex vascular grafts prior to resection of the stenotic area. Initially, an increase in serum bilirubin and alkaline phosphatase levels was noted. Two weeks later, after implantation of the grafts, these values returned to normal. Thin-walled FEP-ringed Gore-Tex vascular grafts were found to be useful in the repair of bile duct injuries, especially in complete transections of the common bile duct. The ductility and flexibility of the material allows any type of anastomosis to be performed, especially when bile duct-gut anastomosis is technically difficult.

  12. Effects of Hydroxyapatite on Bone Graft Resorption in an Experimental Model of Maxillary Alveolar Arch Defects

    Directory of Open Access Journals (Sweden)

    Ozgur Pilanci

    2013-06-01

    Full Text Available Most commonly used treatments use autologous bone grafts to address bony defects in patients with cleft palate. Major disadvantages of autogenous bone grafts include donor site morbidity and resorption. Suggestions to overcome such problems include biomaterials that can be used alone or in combination with bone. We examined the effect of hydroxyapatite cement on bone graft resorption in a rabbit maxillary alveolar defect model. We divided 16 young adult albino New Zealand rabbits into two groups. A defect 1 cm wide was created in each rabbit's maxillary arch. In Group 1, the removed bone was disrupted, and the pieces were replaced in the defect. In the other group, the pieces were replaced after mixing (1:1 with hydroxyapatite cement. Quantitative computed tomographic evaluation of these grafts was performed in axial and coronal planes for each rabbit at 2 and 12 weeks. In axial images at 12 weeks, the group without cement showed mean bone resorption of 15%. In the cement group, a mean volumetric increase of 68% was seen. No resorption occurred when bone grafts were mixed with hydroxyapatite cement. [Arch Clin Exp Surg 2013; 2(3.000: 170-175

  13. Morphology and function of preserved microvascular arterial grafts: an experimental study in rats

    NARCIS (Netherlands)

    Vischjager, M.; van Gulik, T. M.; Kromhout, J. G.; van Marle, J.; Pfaffendorf, M.; Klopper, P. J.; Jacobs, M. J.

    1997-01-01

    The aim of this study is to examine the morphology and function and small-caliber, arterial grafts after preservation in the University of Wisconsin solution (UW). Rat carotid arteries were stored in UW (n = 10) or in phosphate-buffered saline (PBS) (n = 10) for 1, 3, 7, and 14 days and were

  14. Injectable calcium phosphate cement as a graft material for maxillary sinus augmentation: an experimental pilot study.

    NARCIS (Netherlands)

    Aral, A.; Yalcin, S.; Karabuda, Z.C.; Anil, A.; Jansen, J.A.; Mutlu, Z.

    2008-01-01

    OBJECTIVES: The aim of the present study was to evaluate the efficiency of injectable CaP cement as a graft material around dental implants in the maxillary sinus augmentation procedure. MATERIAL AND METHODS: Bilateral sinus augmentation process was carried out in three sheep and two implants were

  15. AI and Prosthetics

    OpenAIRE

    Kyriazi, Nefeli Evdokia

    2016-01-01

    Prosthetics are very important to an amputee.The introduction of technology to prosthetics has allowed bionic limbs to emerge and change the way we were thinking about prosthetic limbs.More and more companies create new innovative models,but not affordable for anyone.3D Printing gives more options.

  16. Graft survival and cytokine production profile after limbal transplantation in the experimental mouse model

    Czech Academy of Sciences Publication Activity Database

    Lenčová, Anna; Pokorná, Kateřina; Zajícová, Alena; Krulová, Magdalena; Filipec, M.; Holáň, Vladimír

    2011-01-01

    Roč. 24, č. 3 (2011), s. 189-194 ISSN 0966-3274 R&D Projects: GA AV ČR KAN200520804; GA MŠk 1M0506; GA ČR GD310/08/H077 Institutional research plan: CEZ:AV0Z50520514 Keywords : limbal transplantation * graft survival * cytokine response Subject RIV: EC - Immunology Impact factor: 1.459, year: 2011

  17. High Hydrostatic Pressure for Disinfection of Bone Grafts and Biomaterials: An Experimental Study

    OpenAIRE

    Gollwitzer, Hans; Mittelmeier, Wolfram; Brendle, Monika; Weber, Patrick; Miethke, Thomas; Hofmann, Gunther O; Gerdesmeyer, Ludger; Schauwecker, Johannes; Diehl, Peter

    2009-01-01

    Background: Autoclaving, heat, irradiation or chemical detergents are used to disinfect autografts, allografts and biomaterials for tissue reconstruction. These methods are often associated with deterioration of mechanical, physical, and biological properties of the bone grafts and synthetic implants. High hydrostatic pressure has been proposed as a novel method preserving biomechanical and biological properties of bone, tendon and cartilage. This is the first study to assess the inactivation...

  18. Interposition vein cuff in infrainguinal prosthetic bypasses.

    Science.gov (United States)

    D'Andrea, V; Biancari, F; Catania, A; Di Matteo, F M; Sorrenti, S; Spyrou, M; Dibra, A; Foti, N; Ortensi, A

    1999-01-01

    The Authors describe the interposition vein cuff technique as an adjuvant method to infrainguinal prosthetic bypass grafts. The haemodynamic, mechanical and humoral factors thought to be involved in the beneficial effects of the vein cuff are herein discussed. The results of the main series suggest the use of this method particularly in patients without any available autologous vein conduit requiring a below-knee popliteal or crural reconstruction.

  19. Experimental study of vascularized nerve graft: evaluation of nerve regeneration using choline acetyltransferase activity.

    Science.gov (United States)

    Iwai, M; Tamai, S; Yajima, H; Kawanishi, K

    2001-01-01

    A comparative study of nerve regeneration was performed on vascularized nerve graft (VNG) and free nerve graft (FNG) in Fischer strain rats. A segment of the sciatic nerve with vascular pedicle of the femoral artery and vein was harvested from syngeneic donor rat for the VNG group and the sciatic nerve in the same length without vascular pedicle was harvested for the FNG group. They were transplanted to a nerve defect in the sciatic nerve of syngeneic recipient rats. At 2, 4, 6, 8, 12, 16, and 24 weeks after operation, the sciatic nerves were biopsied and processed for evaluation of choline acetyltransferase (CAT) activity, histological studies, and measurement of wet weight of the muscle innervated by the sciatic nerve. Electrophysiological evaluation of the grafted nerve was also performed before sacrifice. The average CAT activity in the distal to the distal suture site was 383 cpm in VNG and 361 cpm in FNG at 2 weeks; 6,189 cpm in VNG and 2,264 cpm in FNG at 4 weeks; and 11,299 cpm in VNG and 9,424 cpm in FNG at 6 weeks postoperatively. The value of the VNG group was statistically higher than that of the FNG group at 4 weeks postoperatively. Electrophysiological and histological findings also suggested that nerve regeneration in the VNG group was superior to that in the FNG group during the same period. However, there was no significant difference between the two groups after 6 weeks postoperatively in any of the evaluations. The CAT measurement was useful in the experiments, because it was highly sensitive and reproducible. Copyright 2001 Wiley-Liss, Inc.

  20. Morphological experimental study of bone stress at the interface acetabular bone/prosthetic cup in the bipolar hip prosthesis.

    Science.gov (United States)

    Anuşca, D; Pleşea, I E; Iliescu, N; Tomescu, P; Poenaru, F; Dascălu, V; Pop, O T

    2006-01-01

    By calculating the tension and distortion of the elements composing the bipolar prosthesis under extreme conditions encountered in real life using a special post-processing program, we established the variation curves of the contact pressure at the hip bone-cup, armor-cup and cup-femoral head interface. By comparing the data obtained from all the examined cases, important conclusions were drawn regarding the influence of tension and pressure distribution on the structural integrity and biomechanics of the prosthesis, as well as the acetabular wear and tear, in order to assess its reliability. The experimentally determined tension and distortion status at the acetabular bone-metal armour interface, lead to the wear and tear phenomenon, which can be explained by three mechanisms and theories incompletely reflecting the overall process. The histopathologic study of the acetabular bone tissue using FEM (finite elements method) on surgically removed specimens will probably lead to the identification of a series of factors that could reduce the rate of the wear and tear process.

  1. Efficacy of Seprafilm® graft with adhesiolysis in experimentally induced lid adhesion in rabbits

    Directory of Open Access Journals (Sweden)

    Sang Wook Jin

    2013-02-01

    Full Text Available AIM:To evaluate the efficacy of Seprafilm® transplantation following adhesiolysis for preventing postoperative readhesion and improving surgical outcomes.METHODS:Primary blepharoplasty was carried out on both eyelids of 18 albino rabbits. After 2 weeks, a new skin incision was made, and adhesiolysis was performed on both eyelids. The rabbits were categorized into two groups, one with adhesiolysis alone in the left eyelid (control group, and the other with adhesiolysis with a Seprafilm® graft in the right eyelid (Seprafilm® group. The degrees of inflammation and fibrosis were examined with hematoxylin-eosin (HE and Masson’s trichrome stains. Expression of α-smooth muscle actin (α-SMA was also immunohistochemically examined.RESULTS:Eyelid examination immediately after the operation revealed mild swelling and hemorrhage in both groups, but these symptoms resolved after 1 week-2 weeks, and eyelid shape had recovered completely in both groups. Microscopic assessments demonstrated that the Seprafilm® group showed less inflammation and fibrosis than the control group. The Seprafilm® group also exhibited fewer α-SMA-positive cells than the control group.CONCLUSION:Based on these findings, we conclude that Seprafilm® graft with adhesiolysis is an effective method for preventing postoperative readhesions after eyelid surgery.

  2. High hydrostatic pressure for disinfection of bone grafts and biomaterials: an experimental study.

    Science.gov (United States)

    Gollwitzer, Hans; Mittelmeier, Wolfram; Brendle, Monika; Weber, Patrick; Miethke, Thomas; Hofmann, Gunther O; Gerdesmeyer, Ludger; Schauwecker, Johannes; Diehl, Peter

    2009-01-29

    Autoclaving, heat, irradiation or chemical detergents are used to disinfect autografts, allografts and biomaterials for tissue reconstruction. These methods are often associated with deterioration of mechanical, physical, and biological properties of the bone grafts and synthetic implants. High hydrostatic pressure has been proposed as a novel method preserving biomechanical and biological properties of bone, tendon and cartilage. This is the first study to assess the inactivation of clinically relevant bacteria on biomaterials and human bone by high hydrostatic pressure. Bacterial suspensions of Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecium, implants covered with infected blood, human bone infected in vitro, and biopsies of patients with chronic osteomyelitis were subjected to different protocols of high hydrostatic pressure up to 600 MPa. Bacterial survival after high hydrostatic pressure treatment was determined and compared with bacterial growth in untreated controls. S. aureus and P. aeruginosa in suspension were completely inactivated by high hydrostatic pressure (> 5log levels), whereas E. faecium showed barotolerance up to 600 MPa. Blood and adherence to metal implants did not significantly alter inactivation of bacteria, and complete disinfection was achieved with barotolerant bacteria (S. aureus and P. aeruginosa). However, osteoarthritic bone demonstrated a non-homogeneous baroprotective effect, with single bone samples resistant to treatment resulting in unaltered bacterial growth, and complete disinfection of artificially infected bone specimens was achieved in 66% for S. aureus, 60% for P. aeruginosa and 0% for E. faecium. Human bone samples of patients with chronic osteomyelitis could be completely disinfected in 2 of 37 cases. High hydrostatic pressure offers new perspectives for disinfection of sensitive biomaterials and bone grafts, and contamination by blood did not significantly affect bacterial inactivation rates

  3. Prevention of Prosthetic Dentistry

    Directory of Open Access Journals (Sweden)

    Eremin O.V.

    2011-03-01

    Full Text Available Prevention in prosthetic dentistry is not just a regular oral hygiene and the prevention of caries in the early stages of its development. The initial goal of orthopedic and dental should be the ability to convey to the patient's sense of pros-thetics that proteziruya one saved more. An example is included prosthetic dental arch defects with bridges or single artificial crowns on implants that will prevent movement of teeth and the continuity of the dentition

  4. Chest wall reconstruction with autologas rib grafts in dogs and report of a clinic case.

    Science.gov (United States)

    Tunçözgür, B; Elbeyli, L; Güngör, A; Işik, F; Akay, H

    1999-09-01

    Nowadays, in chest wall reconstruction prosthetic materials are generally used. However, the rejections of prosthetic materials and infections frequently occur in chest wall reconstruction, especially after radiotherapy or resection that is performed due to infections. We used 10 mongrel dogs and performed resections of 8 cm diameter on their chest walls. In the reconstruction of these defects, in five of the subjects, we used two free rib grafts with periosteum to be resected from the contralateral side and in other five subjects, we used free rib grafts without periosteum. After this experimental study, sternal resection was performed in a 24-year-old man because of sternal osteomyelitis. First to obtain rib grafts with periosteum, partial resection was performed to 5th, 7th, and 9th ribs of the lateral left side. After, total sternal resection, end to end anastomosis was performed to the 2nd, 3rd, 4th and 5th anterior ends of the ribs. Autogeneous rib grafts were found to be enough to provide chest wall stabilization. The contralateral autogeneous free rib grafts can successfully be used in reconstruction of wide chest wall defects. This method is found to be effective and sufficient to prevent infection, rejection and to provide stabilization.

  5. Threshold concepts in prosthetics.

    Science.gov (United States)

    Hill, Sophie

    2017-12-01

    Curriculum documents identify key concepts within learning prosthetics. Threshold concepts provide an alternative way of viewing the curriculum, focussing on the ways of thinking and practicing within prosthetics. Threshold concepts can be described as an opening to a different way of viewing a concept. This article forms part of a larger study exploring what students and staff experience as difficult in learning about prosthetics. To explore possible threshold concepts within prosthetics. Qualitative, interpretative phenomenological analysis. Data from 18 students and 8 staff at two universities with undergraduate prosthetics and orthotics programmes were generated through interviews and questionnaires. The data were analysed using an interpretative phenomenological analysis approach. Three possible threshold concepts arose from the data: 'how we walk', 'learning to talk' and 'considering the person'. Three potential threshold concepts in prosthetics are suggested with possible implications for prosthetics education. These possible threshold concepts involve changes in both conceptual and ontological knowledge, integrating into the persona of the individual. This integration occurs through the development of memories associated with procedural concepts that combine with disciplinary concepts. Considering the prosthetics curriculum through the lens of threshold concepts enables a focus on how students learn to become prosthetists. Clinical relevance This study provides new insights into how prosthetists learn. This has implications for curriculum design in prosthetics education.

  6. Laxity of the elbow after experimental excision of the radial head and division of the medial collateral ligament. Efficacy of ligament repair and radial head prosthetic replacement

    DEFF Research Database (Denmark)

    Jensen, S.L.; Deutch, S.R.; Olsen, B.S.

    2003-01-01

    We studied the stabilising effect of prosthetic replacement of the radial head and repair of the medial collateral ligament (MCL) after excision of the radial head and section of the MCL in five cadaver elbows. Division of the MCL increased valgus angulation (mean 3.9 +/- 1.5 degrees) and internal...

  7. Graft copolymerization of acrylic acid to cassava starch-Evaluation of the influences of process parameters by an experimental design method

    NARCIS (Netherlands)

    Witono, J. R.; Noordergraaf, I. W.; Heeres, H. J.; Janssen, L. P. B. M.

    2012-01-01

    The graft copolymerization of cassava starch with acrylic acid was investigated using a free radical initiator system (Fe2+/H2O2 redox system) in water. A comprehensive understanding of the important variables and their interaction has been obtained by applying an experimental design method. In this

  8. Use of platelet-rich plasma solution applied with composite chondrocutaneous graft technique: an experimental study in rabbit model.

    Science.gov (United States)

    Sevim, Kamuran Zeynep; Yazar, Memet; Irmak, Fatih; Tekkeşin, Merva Soluk; Yildiz, Kemalettin; Sirvan, Selami Serhat

    2014-07-01

    Composite chondrocutaneous grafts have been used widely for patients with cleft lip nasal deformity, alar defects, and septal perforations; however, the graft viability can be easily compromised. The aim of the present study was to extend the safe length of the composite chondrocutaneous grafts by enhancement of angiogenesis and re-epithelialization through platelet-rich plasma (PRP) and to investigate the changes that occur when PRP is administered to the graft and the recipient site. Composite grafts of critical sizes (1.5, 2.0, and 2.5 cm) were planned on the rabbit ears on 1 side. Group A consisted of grafts pretreated with PRP, group B consisted of recipient beds pretreated with PRP, and group C was the control group in which defects 1.5, 2.0, and 2.5 cm in size were formed on the right ears of the rabbits. On postoperative day 7, matching size chondrocutaneous grafts were adapted to the defect areas without PRP. In all groups, graft viability was evaluated 7 days after graft adaptation in group C and 14 days after PRP administration in groups A and B. Wound healing was scored histopathologically and immunohistologically using hematoxylin and eosin, CD34, and smooth muscle actin staining. The terminal transferase fluorescein-dUTP nick end labeling assay was performed to quantitatively demonstrate the apoptosis ratio among the groups. In groups A, B, and C, the mean graft survival of the 2.0-cm equilateral triangle-shaped composite grafts was 65.43% ± 15.7%, 78.12% ± 12.8%, and 41.31% ± 37.4%, respectively (P = .0364). PRP pretreatment accelerated composite graft survival in the 2.0-cm equilateral triangle grafts by increasing epithelial regeneration and fibrosis, inducing neovascularization, and ameliorating apoptosis rates. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Biomechanical and histologic comparison of Achilles tendon ruptures reinforced with intratendinous and peritendinous plantaris tendon grafts in rabbits: an experimental study.

    Science.gov (United States)

    Ilhami, Kuru; Gokhan, Maralcan; Ulukan, Inan; Eray, Bozan M; Levent, Altinel; Ciğdem, Tokyol

    2004-11-01

    We hypothesized that the closer the reinforcing graft was to the repair zone, the more strength the healed tendon would achieved. Therefore, we compared the ruptured rabbit Achilles tendons reinforced with intratendinous and peritendinous plantaris grafts. The experimental study was performed on Achilles tendons of 20 rabbits. First, they were divided into two groups: group I (n=10) underwent intratendinous graft and end-to-end tenorraphy, and group P (n=10) were repaired end-to-end and then reinforced with a peritendinous plantaris graft. An above-knee cast was applied during 6 weeks postoperatively. The two groups were compared to each other biomechanically and histologically. Seven randomly selected rabbits from each group were used for biomechanical evaluation. The remaining six rabbits (three from each group) were used for histologic comparison. Non-operated sides (n=20) served as the control group. The mean maximum load at rupture of the repaired and control groups was 159.9+/-31 N, 83+/-7.5 N, and 207.5+/-35 N for group I, group P, and the control group, respectively. Values between groups were significantly different considering maximum load and absorbed energy to rupture. There was no significant difference between groups I and P in respect to strain. Control group tendons (groups I-C and P-C) had significantly more lengthening capability than operated tendons. Macroscopically, group I tendons were thicker and stiffer than group P tendons. Histologically, differences between the group I and group P specimens revealed that the healing process was faster in tendons augmented intratendinously. In reinforcing Achilles tendon repair, the site of the tendon graft affected the result. When the graft was used intratendinously, the healed tendon was more similar biomechanically to normal tendon and had more graft-tendon orientation histologically than the tendon augmented peritendinously.

  10. Improved transjugular intrahepatic portosystemic shunt patency with PTFE-covered stent-grafts: experimental results in swine.

    Science.gov (United States)

    Nishimine, K; Saxon, R R; Kichikawa, K; Mendel-Hartvig, J; Timmermans, H A; Shim, H J; Uchida, B T; Barton, R E; Keller, F S; Rösch, J

    1995-08-01

    To evaluate the ability of stent-grafts made with polytetrafluoroethylene (PTFE) graft material to improve transjugular intrahepatic portosystemic shunt (TIPS) patency. TIPS were created in 13 swine by using PTFE-covered stent-grafts. Uncovered TIPS were placed in 13 other swine. Twenty-one of 26 animals were followed up with portal venography for 3 months or until the shunt became severely stenotic. Five animals without severe stenosis were sacrificed before 3 months because of illness. At 4 weeks after TIPS placement, nine of 13 stent-graft TIPS were patent (late shunt malfunction in selected cases.

  11. GIANT PROSTHETIC VALVE THROMBUS

    Directory of Open Access Journals (Sweden)

    Prashanth Kumar

    2015-04-01

    Full Text Available Mechanical prosthetic valves are predisposed to bleeding, thrombosis & thromboembolic complications. Overall incidence of thromboembolic complications is 1% per year who are on oral anticoagulants, whereas bleeding complications incidence is 0.5% to 6.6% per year. 1, 2 Minimization of Scylla of thromboembolic & Charybdis of bleeding complication needs a balancing act of optimal antithrombotic therapy. We are reporting a case of middle aged male patient with prosthetic mitral valve presenting in heart failure. Patient had discontinued anticoagulants, as he had subdural hematoma in the past. He presented to our institute with a giant prosthetic valve thrombus.

  12. Prosthetic training: upper limb.

    Science.gov (United States)

    Johnson, Shawn Swanson; Mansfield, Elizabeth

    2014-02-01

    Ideally, a collaborative team approach is already in place between the certified prosthetist (CP) and the occupational therapist (OT) before patients are casted for a prosthesis. Once an individual has completed their preprosthetic rehabilitation program and received an operational prosthesis from a CP, it is imperative that an OT provides prosthetic training. Prosthetic training is necessary so that the individual can learn how to use and incorporate the prosthesis into their daily life. Prosthetic training consists of 3 main phases: controls training, repetitive drills, and bimanual functional skill training. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. An experimental study on inhibiting graft rejection following high-risk penetrating keratoplasty by CD25 siRNA nanocarrier in rats

    Directory of Open Access Journals (Sweden)

    Yun-jie SHI

    2015-06-01

    RNA in the experimental group was significantly lower at every single time points. Conclusions CD25siRNA gene transfer could successfully down-regulate CD25 expression, inhibit graft rejection and prolong the survival time of allogeneic corneal graft. DOI: 10.11855/j.issn.0577-7402.2015.04.09

  14. Protection of intestinal anastomoses in septic environment with peritoneal graft and polyglycolic acid mesh: an experimental study.

    Science.gov (United States)

    Dilek, O N; Bakir, B; Dilek, F H; Demirel, H; Yiğit, M F

    1996-01-01

    We carried out an experimental study in dogs to evaluate the outcome of large bowel anastomosis with 6 stitches (Group C, n : 6) in a septic environment with protection by a polyglycolic acid (PGA) mesh (Group M, n : 12) or peritoneal graft (Group P, n : 12). Thirty dogs were used to compare the techniques. Two dogs in each group were re-operated after 3, 5, 7, 14, 28 and 90 days. They were evaluated for adhesion formation, lumen diameter (anastomotic index), clinical features, histologic appearance and quality of healing at the anastomotic sites. All dogs in group P and group M survived, whereas 2 dogs in the control group died of anastomotic leakage and 3 dogs were re-operated for anastomotic leakage and peritonitis. In group M, one dog was reoperated because of the anastomotic leakage and two dogs were reoperated because of the anastomotic stenosis. Also, 4 anastomoses showed evidence of moderate stenosis. In group P, three anastomoses were graded as minimal stenosis. Histopathologic evaluation showed more complete epithelization, less inflammation, and less adhesion in group P than group M. We could not find any study in the literature that described and compared both techniques. We report here the results of such a study.

  15. Prosthetic Care FAQs

    Science.gov (United States)

    ... are healthcare professionals that have demonstrated knowledge and competence in the field of prosthetics. Their qualifications include a ... issues. Prosthetists are allied health professionals and experts in designing and ... information, resources and advice to patients and their healthcare ...

  16. A comparison of one- versus two-stage surgery in an experimental model of functional muscle transfer with interposed nerve grafting.

    Science.gov (United States)

    Urso-Baiarda, F; Grobbelaar, A O

    2009-08-01

    Functional muscle transfer (FMT) combined with cross-facial nerve grafting (CFNG) is the gold standard treatment of chronic unilateral facial palsy, performed by most surgeons over two operative stages to minimise FMT denervation atrophy. Proponents of one-stage surgery cite shorter total recovery time, fewer operative procedures and a possible beneficial neurotrophic effect of muscle attachment. This study aimed to compare one- and two-stage surgery in terms of neural and muscle reinnervation and FMT force production. Forty New Zealand white rabbits underwent one- or two-stage rectus femoris FMT and interposed nerve grafting under different reinnervation conditions. For two-stage surgery, nerve grafting was followed by FMT after three months and by final experiments after a further six months, whereas one-stage groups experienced nerve grafting and FMT together and final experiments after nine months. Outcomes compared were nerve graft and rectus nerve morphometry, FMT reinnervation measured using PGP 9.5, and FMT force production. Statistical analysis was performed by means of the independent samples t-test or the Mann-Whitney Rank Sum test using Statistics Package for the Social Sciences version 11.0.4 for Mac OS X. Nerve graft reinnervation was similar for respective one- and two-stage surgery groups or favoured one-stage surgery. There was no significant difference between respective groups in terms of rectus nerve morphometry, muscle reinnervation, or absolute, weight-adjusted or weight- and control-adjusted tetanic force production. One-stage surgery offers potential advantages including a reduction in the number of surgical procedures, a shorter total recovery time and beneficial economic and healthcare delivery implications. This data supports previous clinical and experimental studies and questions the basis for performing facial reanimation by FMT combined with CFNG over two separate operative stages.

  17. Effects of the Diabetic Condition on Grafted Fat Survival: An Experimental Study Using Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Jae A Jung

    2014-05-01

    Full Text Available Background Autologous fat grafts have been widely used for cosmetic purposes and for soft tissue contour reconstruction. Because diabetes mellitus is one of the major chronic diseases in nearly every country, the requirement for fat grafts in diabetes patients is expected to increase continuously. However, the circulation complications of diabetes are serious and have been shown to involve microvascular problems, impairing ischemia-driven neovascularization in particular. After injection, revascularization is vital to the survival of the grafted fat. In this study, the authors attempted to determine whether the diabetic condition inhibits the survival of injected fat due to impaired neovascularization. Methods The rat scalp was used for testing fat graft survival. Forty-four seven-week-old male Sprague-Dawley rats were allocated to a diabetic group or a control group. 1.0 mL of processed fat was injected subcutaneously into the scalp of each rat. The effect of diabetes was evaluated by calculating the volume and the weight of the grafted fat and by histologically analyzing the fat sections. Results The surviving fat graft volume and weight were considerably smaller in the diabetic group than in the control group (P<0.05, and histological evaluations showed less vascularity, and more cysts, vacuoles, and fibrosis in the diabetic group (P<0.05. Cellular integrity and inflammation were not considerably different in the two groups. Conclusions As the final outcome, we found that the presence of diabetes might impair the survival and the quality of fat grafts, as evidenced by lower fat graft weights and volumes and poor histologic graft quality.

  18. Topical application of sodium hyaluronate for preventing perivascular adhesion of the vein grafts in rabbits: An experimental study

    Directory of Open Access Journals (Sweden)

    Ming-ke GUO

    2017-10-01

    Full Text Available Objective To explore the effect of topical application of sodium hyaluronate on preventing perivascular adhesion of the vein grafts in rabbits. Methods Thirty-six male New Zealand white rabbits, aged 5 months, were randomly and equally divided into 2 groups: groups A and B. Arterial defect model was established by cutting about 1cm artery from the middle part of the dissected left common carotid artery. A section about 3cm was cut from the right external jugular vein, and the harvested vein was inverted and anastomosed end-to-end to the artery defect. After the anastomosis, the adventitia and two anastomoses of the grafted veins in group A were coated locally with 0.2ml sodium hyaluronate. The grafted veins were obtained 1, 2 and 4 weeks after the operation, with the perivascular adhesion of the vein grafts being examined macroscopically before the resection. HE staining and Masson staining were preformed for histological changes of grafted vein wall and the perivascular adhesion of the vein grafts. At 2, 4 weeks postoperation, the perivascular adhesions of the vein grafts were graded by the grading criteria of adhesion in macroscopic evaluation and histological evaluation. Results At 1, 2 and 4 weeks postoperatively, the macroscopic and histological observation found that the perivascular adhesions in group A were looser than those in group B. The macroscopic grade and histological grade were lower in group A than in group B, there was a significant difference between the two groups at 2 and 4 weeks postoperation (P<0.05. Conclusion Topical application of sodium hyaluronate can reduce the perivascular adhesion and is an ideal treatment strategy for preventing perivascular adhesion of vein grafts. DOI: 10.11855/j.issn.0577-7402.2017.08.14

  19. Experimental and theoretical studies of xanthan gum and its graft co-polymer as corrosion inhibitor for mild steel in 15% HCl

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Amrita; Pal, Sagar; Udayabhanu, G., E-mail: g_udayabhanu@hotmail.com

    2015-10-30

    Highlights: • Xanthan gum and its graft co-polymer used as corrosion inhibitors for mild steel in 15% HCl. • Electrochemical and weight loss studies give comparable corrosion rates. • Both the inhibitors are mixed type in nature. • Modified graft co-polymer is a more effective corrosion inhibitor. • Theoretical calculations taking monomer units of the polymer support the experimental results. - Abstract: Xanthan gum (XG) and its graft co-polymer have been investigated as corrosion inhibitors for mild steel in 15% HCl. Gravimetric analysis, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods were employed for investigating the effectiveness of these inhibitors. Results indicate that both the inhibitors are of mixed type and follow Langmuir adsorption isotherm. Scanning electron microscopy (SEM) study also confirmed the protection of the metal surface by XG and xanthan gum-graft-poly(acrylamide) (XG-g-PAM). Theoretical calculations using Density Functional Theory (DFT) were used to establish the correlation between the structure and corrosion protection efficiencies.

  20. The Prosthetic Experience Between Body and Technology

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2018-01-01

    In this paper, I argue that a prosthetic aesthetic instigated by experimental art practices operate with and within a ‘second nature’ – in-between science and art. Drawing on theories from Dewey and Edelman and examples from Da Vinci, Brancusi, Man Ray, Dali and Stelarc, I am calling for an exper...

  1. The Prosthetic Experience Between Body and Technology

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2018-01-01

    In this paper, I argue that a prosthetic aesthetic instigated by experimental art practices operate with and within a ‘second nature’ – in-between science and art. Drawing on theories from Dewey and Edelman and examples from Da Vinci, Brancusi, Man Ray, Dali and Stelarc, I am calling...

  2. The experimental treatment of corneal graft rejection with the interleukin-1 receptor antagonist (IL-1ra gene.

    Directory of Open Access Journals (Sweden)

    Jin Yuan

    Full Text Available PURPOSE: To investigate the protective effects of interleukin-1 receptor antagonist (IL-1ra gene transfer in a rat model of corneal graft rejection. METHODS: We constructed a recombinant plasmid (pcDNA3.1-hIL-1ra with high IL-1ra expression in eukaryotic cells. Using a Wistar-SD rat model of corneal graft rejection, we examined the effects of IL-1ra in vivo after cationic polymer jetPEI-mediated nonviral gene delivery. Four groups were included: negative controls (group I, n = 20, pcDNA3.1-hIL-1ra corneal stromal injection (group II, n = 34, pcDNA3.1-hIL-1ra anterior chamber injection (group III, n = 34, and 500 µg/ml IL-1ra protein subconjunctiva injection (group IV, n = 20. IL-1ra expression after transfection was evaluated by real-time polymerase chain reaction (RT-PCR and western blotting. The rejection indices of corneal grafts were analysed in the different groups. The expression levels of transforming growth factor β1 (TGF-β1, inflammatory chemokines including RANTES, interleukin-1 (IL-1 and the numbers of CD4+ and CD8+ T cells in the grafts were determined by biochemical assays at different time points after corneal transplantation. RESULTS: Various degrees of inflammatory cell infiltration and graft neovascularisation were observed by histopathology. After injecting the pcDNA3.1-hIL-1ra plasmid into the cornea, IL-1ra mRNA and protein expression was detected in the corneal stroma and reached a peak on day 3. The graft survival curves indicated that the corneal transparency rates of grafts in the IL-1ra gene-treated group and the IL-1ra protein-treated group were higher compared with the untreated group (P<0.05. During the period of acute rejection, TGF-β1, RANTES, IL-1α and IL-1β levels in the grafts in the IL-1ra treatment groups were lower than the control group (P<0.05. CD4+ and CD8+ T cell counts were reduced significantly in the corneal grafts of groups II, III and IV compared with group I (P<0.05. CONCLUSION

  3. Dimensional changes in soft tissues around dental implants following free gingival grafting: an experimental study in dogs.

    Science.gov (United States)

    Bengazi, Franco; Lang, Niklaus P; Caroprese, Marino; Urbizo Velez, Joaquin; Favero, Vittorio; Botticelli, Daniele

    2015-02-01

    To study the buccal dimensional tissue changes at oral implants following free gingival grafting, with or without including the keratin layer, performed at the time of implant installation into alveolar mucosa. The mandibular premolars and first molars were extracted bilaterally in six Beagle dogs. In the right side of the mandible (Test), flaps were first elevated, and the buccal as well as part of the lingual masticatory mucosa was removed. An incision of the periosteum at the buccal aspect was performed to allow the flap to be coronally repositioned. Primary wound closure was obtained. In the left side, the masticatory (keratinized) mucosa was left in situ, and no sutures were applied (Control). After 3 months of healing, absence of keratinized mucosa was confirmed at the test sites. Two recipient sites were prepared at each side of the mandible in the region of the third and fourth premolars. All implants were installed with the shoulder placed flush with the buccal alveolar bony crest, and abutments were connected to allow a non-submerged healing. Two free gingival mucosal grafts were harvested from the buccal region of the maxillary canines. One graft was left intact (gingival mucosal graft), while for the second, the epithelial layer was removed (gingival connective tissue graft). Subsequently, the grafts were fixed around the test implants in position of the third and fourth premolars, respectively. After 3 months, the animals were euthanized and ground sections obtained. Similar bony crest resorption and coronal extension of osseointegration were found at test and control sites. Moreover, similar dimensions of the peri-implant soft tissues were obtained at test and control sites. The increase in the alveolar mucosal thickness by means of a gingival graft affected the peri-implant marginal bone resorption and soft tissue recession around implants. This resulted in outcomes that were similar to those at implants surrounded by masticatory mucosa, indicating

  4. DARPA Revolutionizing Prosthetics 2009

    Science.gov (United States)

    2009-01-01

    reaching, pointing, grasping, and coordinated finger movements to the design of this prosthetic.  Understand and address the amputees ’ needs to promote and...filled bladders 3. Vacuum attachment methods 4. Electro-active Polymers 5. Shape changing material structures Cosmesis  Exploring alternative materials

  5. Reconstruction of mandibular defects after radiation, using a free, living bone, graft transferred by microvascular anastomoses. An experimental study

    International Nuclear Information System (INIS)

    Ostrup, L.T.; Fredrickson, J.M.

    1975-01-01

    The replacement of a mandibular defect by a free, composite rib graft, transferred by microvascular anastomoses of the posterior intercostal vessels to donor vessels in the neck was described previously. We now present data which demonstrate that successful results can be achieved even after radical mandibular radiation. This technique, done in dogs, has obvious implications in the management of oral cancer in man

  6. Calcar bone graft

    Energy Technology Data Exchange (ETDEWEB)

    Bargar, W.L.; Paul, H.A.; Merritt, K.; Sharkey, N.

    1986-01-01

    A canine model was developed to investigate the use of an autogeneic iliac bone graft to treat the calcar deficiency commonly found at the time of revision surgery for femoral component loosening. Five large male mixed-breed dogs had bilateral total hip arthroplasty staged at three-month intervals, and were sacrificed at six months. Prior to cementing the femoral component, an experimental calcar defect was made, and a bicortical iliac bone graft was fashioned to fill the defect. Serial roentgenograms showed the grafts had united with no resorption. Technetium-99 bone scans showed more uptake at three months than at six months in the graft region. Disulfine blue injection indicated all grafts were perfused at both three and six months. Thin section histology, fluorochromes, and microradiographs confirmed graft viability in all dogs. Semiquantitative grading of the fluorochromes indicated new bone deposition in 20%-50% of each graft at three months and 50%-80% at six months. Although the calcar bone graft was uniformly successful in this canine study, the clinical application of this technique should be evaluated by long-term results in humans.

  7. Transplantation and microsurgical anastomosis of free omental grafts: experimental animal model of a new operative technique in dogs.

    Science.gov (United States)

    Pap-Szekeres, Jozsef; Cserni, Gabor; Furka, Istvan; Svebis, Mihaly; Cserni, Tamas; Brath, Endre; Nemeth, Norbert; Miko, Iren

    2003-01-01

    Our objective was the elaboration of a new animal model for the free transplantation of an omental flap and the examination of its viability in dogs. The cooled omental flap from the abdomen was freely transplanted to the lateral cervical region, and its blood supply was established with microsurgical anastomoses. The technique was developed in 5 dogs, and short-term survival examinations were later carried out in 3 cases by means of this method. Postoperative viability was assessed by angiography, methylene blue testing, and histology. Of the 3 transplanted grafts, 2 still survived 1 week after the operation. For technical reasons, 1 flap thrombotized. For determination of the viability of the transplanted graft, histology proved best. Vital reactions, including granulation tissue and angiogenesis, were present on the histological slides. The short-term survival of an omental flap can be ensured with microsurgical transplantation in dogs. Copyright 2003 Wiley-Liss, Inc.

  8. Some Theoretical and Experimental Insights on the Mechanistic Routes Leading to the Spontaneous Grafting of Gold Surfaces by Diazonium Salts.

    Science.gov (United States)

    Berisha, Avni; Combellas, Catherine; Kanoufi, Frédéric; Decorse, Philippe; Oturan, Nihal; Médard, Jérôme; Seydou, Mahamadou; Maurel, François; Pinson, Jean

    2017-09-05

    The spontaneous grafting of diazonium salts on gold may involve the carbocation obtained by heterolytic dediazonation and not necessarily the radical, as usually observed on reducing surfaces. The mechanism is addressed on the basis of DFT calculations and experiments carried out under conditions where the carbocation and the radical are produced selectively. The calculations indicate that the driving force of the reaction leading from a gold cluster, used as a gold model surface, and the carbocation to the modified cluster is higher than that of the analogous reaction starting from the radical. The experiments performed under conditions of heterolytic dediazonation show the formation of thin films on the surface of gold. The grafting of a carbocation is therefore possible, but a mechanism where the cleavage of the Ar-N bond is catalyzed by the surface of gold cannot be excluded.

  9. Welding of Prosthetic Alloys

    Directory of Open Access Journals (Sweden)

    Wojciechowska M.

    2015-04-01

    Full Text Available This paper presents the techniques of joining metal denture elements, used in prosthetic dentistry: the traditional soldering technique with a gas burner and a new technique of welding with a laser beam; the aim of the study was to make a comparative assessment of the quality of the joints in view of the possibility of applying them in prosthetic structures. Fractographic examinations were conducted along with tensile strength and impact strength tests, and the quality of the joints was assessed compared to the solid metal. The experiments have shown that the metal elements used to make dentures, joined by the technique which employs a laser beam, have better strength properties than those achieved with a gas burner.

  10. Prosthetics in Paediatric Dentistry

    Directory of Open Access Journals (Sweden)

    Vulićević Zoran

    2017-07-01

    Full Text Available Premature loss of teeth in children may lead to both functional and esthetic problems. Missing teeth in both anterior and posterior regions may cause malfunctions in mastication and proper pronunciation. If the missing teeth are not replaced, further complications may occur, including adjacent tooth migration, loss of alveolar bone, and irregular occlusion. Considering the sensitive nature of children, loss of teeth may cause the development of insecurities and low self esteem problems. Due to dynamic nature of growth in children and adolescents, prosthetic appliances must not hinder development of orofacial system, and must meet adequate esthetic and functional standards. Dental prosthetic appliances in paediatrics must be planned with respect to the special conditions that led to tooth loss or damage. Multi-disciplinary approach is needed, under constant supervision of paediatric dentist and orthodontist, as well as regular checkups with clinical and radiographical examinations.

  11. Prosthetics in Facial Reconstruction.

    Science.gov (United States)

    Klimczak, Jaclyn; Helman, Samuel; Kadakia, Sameep; Sawhney, Raja; Abraham, Manoj; Vest, Allison K; Ducic, Yadranko

    2018-03-01

    Reconstruction of the head and neck can be a challenging undertaking owing to numerous considerations for successful rehabilitation. Although head and neck defects were once considered irretrievably morbid and associated with a poor quality of life, advances in surgical technique has immensely contributed to the well-being of these patients. However, all patients are not suitable surgical candidates and many have sought nonsurgical options for functional and cosmetic restoration. As such, the advent of prostheses has ameliorated those concerns and provided a viable alternative for select patient populations. Prosthetic reconstruction has evolved significantly over the past decade. Advances in biocompatible materials and imaging adjuncts have spurred further discovery and forward progress. A multidisciplinary approach to head and neck reconstruction focused on appropriate expectations and patient-centered goals is most successfully coordinated by a team of head and neck surgeons, maxillofacial surgeons, and prosthetic specialists. The aim of this article is to provide a comprehensive review of the current trends for prosthetic rehabilitation of head and neck defects, and further elaborate on the limitations and advancements in the field.

  12. Temporomandibular joint reconstruction with a 2-part chrome-cobalt prosthesis, chondro-osseous graft, and silastic: clinical and experimental studies.

    Science.gov (United States)

    Kummoona, Raja

    2009-11-01

    Seventy-six patients including 27 females and 49 males, with ages ranging between 4 and 35 years (mean, 19.5 y), all experienced loss of weight, stiff temporomandibular joints and inability to chew food, and facial deformities. These patients were treated in the Maxillofacial Unit, Surgical Specialties Hospital, Medical City, Baghdad, Iraq, using 4 different techniques according to the requirement of each case and the facilities available. These patients were divided into 4 groups: the first group consists of 16 children (21.06%) treated with a chondro-osseous graft; the second group, 10 children (13.16%) treated with a 2-part chrome-cobalt prosthesis; the third group, 32 children (42.11%) treated with a Sialastic rubber silicone implant (Koken Co, Tokyo, Japan); and the fourth group, 18 children (23.69%) treated with interposition arthroplasty with a temporalis muscle flap. The follow-up period of the cases ranged between 3 and 15 years. Experimental studies were done on using rabbits to assess the viability of the chondro-osseous graft and on monkeys to demonstrate the biological acceptability of the 2-part chrome-cobalt prosthesis. The aim of this clinical and experimental study was to show our experience in managing difficult tasks that craniofacial or maxillofacial surgeons may face and to share these experiences with other colleagues all over the world.

  13. Catheter-based tricuspid valve replacement: first experimental data of a newly designed bileaflet stent graft prosthesis.

    Science.gov (United States)

    Lausberg, Henning F; Gryszkiewicz, Rafal; Kuetting, Maximilian; Baumgaertner, Moritz; Centola, Marcos; Wendel, Hans-Peter; Nowak-Machen, Martina; Schibilsky, David; Kruger, Tobias; Schlensak, Christian

    2017-07-01

    Moderate or severe degree tricuspid valve regurgitation (TVR) is associated with high rates of morbidity and mortality. Surgical correction as the only therapeutic option offers unsatisfactory results. Recently, several interventional procedures have been introduced clinically in a limited cohort. We present our initial experiments with an innovative interventional valved stent graft for treatment of TVR. A newly designed porcine pericardium-covered nitinol stent graft with a lateral bicuspid valve was adapted to size in a cadaver study. After haemodynamic testing in an ex vivo perfusion setup, vascular access, valve delivery and function were investigated in an ovine animal model ( n  = 7). The device was implanted successfully in all animals. Vascular access was established surgically via the femoral vein without any vascular complications. Angiography demonstrated the correct position of the device with proper sealing of both venae cavae in 6 animals. In 1 extremely large animal, the position of the device was considered too cranial but still acceptable. Correct valve function was verified in all animals by both angiography and echocardiography. There were no persistent arrhythmias other than during valve implant. All animals survived the implant procedure and were sacrificed electively. This study demonstrated that this new valved stent graft could be delivered safely with correct positioning and valve function in this ovine model. Further long-term studies in animals implanted with the device after creation of tricuspid regurgitation are necessary to prove the haemodynamic benefit of this procedure. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  14. Effects of exogenous surfactant on the non-heart-beating donor lung graft in experimental lung transplantation – a stereological study

    Science.gov (United States)

    Herrmann, Gudrun; Knudsen, Lars; Madershahian, Navid; Mühlfeld, Christian; Frank, Konrad; Rahmanian, Parwis; Wahlers, Thorsten; Wittwer, Thorsten; Ochs, Matthias

    2014-01-01

    The use of non-heart-beating donor (NHBD) lungs may help to overcome the shortage of lung grafts in clinical lung transplantation, but warm ischaemia and ischaemia/reperfusion injury (I/R injury) resulting in primary graft dysfunction represent a considerable threat. Thus, better strategies for optimized preservation of lung grafts are urgently needed. Surfactant dysfunction has been shown to contribute to I/R injury, and surfactant replacement therapy is effective in enhancing lung function and structural integrity in related rat models. In the present study we hypothesize that surfactant replacement therapy reduces oedema formation in a pig model of NHBD lung transplantation. Oedema formation was quantified with (SF) and without (non-SF) surfactant replacement therapy in interstitial and alveolar compartments by means of design-based stereology in NHBD lungs 7 h after cardiac arrest, reperfusion and transplantation. A sham-operated group served as control. In both NHBD groups, nearly all animals died within the first hours after transplantation due to right heart failure. Both SF and non-SF developed an interstitial oedema of similar degree, as shown by an increase in septal wall volume and arithmetic mean thickness as well as an increase in the volume of peribron-chovascular connective tissue. Regarding intra-alveolar oedema, no statistically significant difference could be found between SF and non-SF. In conclusion, surfactant replacement therapy cannot prevent poor outcome after prolonged warm ischaemia of 7 h in this model. While the beneficial effects of surfactant replacement therapy have been observed in several experimental and clinical studies related to heart-beating donor lungs and cold ischaemia, it is unlikely that surfactant replacement therapy will overcome the shortage of organs in the context of prolonged warm ischaemia, for example, 7 h. Moreover, our data demonstrate that right heart function and dysfunctions of the pulmonary vascular bed

  15. Prosthetic elbow joint

    Science.gov (United States)

    Weddendorf, Bruce C. (Inventor)

    1994-01-01

    An artificial, manually positionable elbow joint for use in an upper extremity, above-elbow, prosthetic is described. The prosthesis provides a locking feature that is easily controlled by the wearer. The instant elbow joint is very strong and durable enough to withstand the repeated heavy loadings encountered by a wearer who works in an industrial, construction, farming, or similar environment. The elbow joint of the present invention comprises a turntable, a frame, a forearm, and a locking assembly. The frame generally includes a housing for the locking assembly and two protruding ears. The forearm includes an elongated beam having a cup-shaped cylindrical member at one end and a locking wheel having a plurality of holes along a circular arc on its other end with a central bore for pivotal attachment to the protruding ears of the frame. The locking assembly includes a collar having a central opening with a plurality of internal grooves, a plurality of internal cam members each having a chamfered surface at one end and a V-shaped slot at its other end; an elongated locking pin having a crown wheel with cam surfaces and locking lugs secured thereto; two coiled compression springs; and a flexible filament attached to one end of the elongated locking pin and extending from the locking assembly for extending and retracting the locking pin into the holes in the locking wheel to permit selective adjustment of the forearm relative to the frame. In use, the turntable is affixed to the upper arm part of the prosthetic in the conventional manner, and the cup-shaped cylindrical member on one end of the forearm is affixed to the forearm piece of the prosthetic in the conventional manner. The elbow joint is easily adjusted and locked between maximum flex and extended positions.

  16. Prosthetic Joint Infection

    Science.gov (United States)

    Tande, Aaron J.

    2014-01-01

    SUMMARY Prosthetic joint infection (PJI) is a tremendous burden for individual patients as well as the global health care industry. While a small minority of joint arthroplasties will become infected, appropriate recognition and management are critical to preserve or restore adequate function and prevent excess morbidity. In this review, we describe the reported risk factors for and clinical manifestations of PJI. We discuss the pathogenesis of PJI and the numerous microorganisms that can cause this devastating infection. The recently proposed consensus definitions of PJI and approaches to accurate diagnosis are reviewed in detail. An overview of the treatment and prevention of this challenging condition is provided. PMID:24696437

  17. Transplante lobar experimental em suínos: enxerto proporcional na disparidade entre receptor e doador Experimental lobar transplantation in swine: proportional graft in the discrepancy between donor and recipient

    Directory of Open Access Journals (Sweden)

    Nuno Ferreira de Lima

    1999-04-01

    Full Text Available Objetivo - Perante a crítica falta de orgãos disponíveis para transplante, a doação intervivos de lobos ou segmentos pulmonares é possível e necessária no transplante pulmonar pediátrico. Na grande disparidade de tamanho do doador adulto e a criança pequena receptora, o lobo médio ou segmento pulmonar representa um enxerto de restrito leito vascular. Este estudo experimental testa a hipótese de que esse tipo de enxerto pode desenvolver hipertensão pulmonar no animal receptor, ao final do período de crescimento. Métodos - Foi utilizado um modelo de sobrevivência de transplante pulmonar à esquerda em leitões. Constituíram-se três grupos de comparação: I (n = 4 - transplante de lobo superior de doador adulto, enxerto proporcional ao receptor, mas irrigado por apenas dois ramos arteriais; II (n = 5 - transplante de lobo inferior de doador adulto, enxerto desproporcional ao receptor e com amplo leito vascular; III (n = 6 - transplante de pulmão imaturo de leitão doador proporcionado. Os animais transplantados tiveram a função do enxerto pulmonar estudada ao final de 3 meses, quando completaram o período de crescimento. Resultados - A pressão da artéria pulmonar do enxerto do grupo I (51,8 ± 2,1mmHg foi mais elevada do que no grupo II (40,4 ± 2,5mmHg e do que no grupo III (34,8 ± 1,5mmHg, atingindo significância estatística (p = 0,0003. Conclusões - O enxerto lobar proporcional ao receptor, mas de leito vascular restrito, teve desempenho hemodinâmico comprometido no animal em crescimento. Esses dados sugerem que a proporcionalidade do enxerto não deve ser prioritária e, antes, ser secundária a um adequado leito vascular do enxerto.Background - The critical donor shortage in pediatric pulmonary transplantation has prompted lobar transplantation from living-related. However, in the case of great size discrepancy between the adult donor and the small child recipient, a pulmonary segment or medium lobe represents

  18. Autologous grafting of extraocular muscles: experimental study in rabbits Transplante autólogo de musculatura ocular extrínseca: estudo experimental em coelhos

    Directory of Open Access Journals (Sweden)

    Jorge Meireles-Teixeira

    2005-06-01

    Full Text Available PURPOSE: To evaluate the feasibility of autologous extraocular muscle grafting as a type of muscle expansion surgery. METHODS: The left superior rectus muscle of twenty-nine rabbits was resected and this fragment was attached to the endpoint of the respective right superior rectus (test group. Thereafter, the superior rectus of the left eye was reattached to the sclera (control group. Both groups were examined during different postoperative periods in order to assess their outcomes. RESULTS: The presence of hyperemia was slightly more frequent in the grafted group. Secretion and muscle atrophy were negligible in both groups. Fibrosis was greater in grafted animals. These muscles were weaker than the control muscles, although the force required to split muscular parts was always greater than the physiological one. CONCLUSIONS: This surgical technique was reliable and useful if one intends to achieve muscle expansion without the intrinsic risks of dealing with heterologous/artificial materials.OBJETIVO: Avaliar a viabilidade do uso de segmentos de músculos oculares extrínsecos como expansores de tendões musculares. MÉTODOS: Vinte e nove coelhos tiveram seu músculo reto superior esquerdo ressecado e o fragmento de cada um foi transplantado para o reto superior contralateral (grupo-teste. Então, o reto superior esquerdo foi reinserido na esclera (grupo-controle. Os animais foram então examinados em diversos períodos pós-operatórios, até os seus sacrifícios, para que se avaliasse o desenrolar dessa técnica cirúrgica. RESULTADOS: A hiperemia foi maior entre os testes. A secreção e a atrofia muscular foram mínimas nos dois grupos. Houve maior presença de fibrose no grupo-teste, mas não tão expressiva a ponto de inviabilizar os efeitos da cirurgia. Esses músculos também se romperam mais facilmente do que os do grupo-controle, porém, a força de rompimento foi sempre bem maior do que aquela presente numa contração muscular normal

  19. The effect of cartilage and bone density of mushroom-shaped, photooxidized, osteochondral transplants: an experimental study on graft performance in sheep using transplants originating from different species

    Directory of Open Access Journals (Sweden)

    Hilbe Monika

    2005-12-01

    Full Text Available Abstract Background Differences in overall performance of osteochondral photooxidized grafts were studied in accordance of their species origin and a new, more rigorous cleansing procedure using alcohol during preparation. Methods Photooxidized mushroom-shaped grafts of bovine, ovine, human and equine origin were implanted in the femoral condyles of 32 sheep (condyles: n = 64. No viable chondrocytes were present at the time of implantation. Grafts were evaluated at 6 months using plastic embedded sections of non-decalcified bone and cartilage specimens. Graft incorporation, the formation of cyst-like lesions at the base of the cartilage junction as well as cartilage morphology was studied qualitatively, semi-quantitatively using a score system and quantitatively by performing histomorphometrical measurements of percentage of bone and fibrous tissue of the original defects. For statistical analysis a factorial analysis of variance (ANOVA- test was applied. Results Differences of graft performance were found according to species origin and cleansing process during graft preparation. According to the score system cartilage surface integrity was best for equine grafts, as well as dislocation or mechanical stability. The equine grafts showed the highest percentage for bone and lowest for fibrous tissue, resp. cystic lesions. The new, more rigorous cleansing process decreased cartilage persistence and overall graft performance. Conclusion Performance of grafts from equine origin was better compared to bovine, ovine and human grafts. The exact reason for this difference was not proven in the current study, but could be related to differences in density of cartilage and subchondral bone between species.

  20. Pursuing prosthetic electronic skin

    Science.gov (United States)

    Chortos, Alex; Liu, Jia; Bao, Zhenan

    2016-09-01

    Skin plays an important role in mediating our interactions with the world. Recreating the properties of skin using electronic devices could have profound implications for prosthetics and medicine. The pursuit of artificial skin has inspired innovations in materials to imitate skin's unique characteristics, including mechanical durability and stretchability, biodegradability, and the ability to measure a diversity of complex sensations over large areas. New materials and fabrication strategies are being developed to make mechanically compliant and multifunctional skin-like electronics, and improve brain/machine interfaces that enable transmission of the skin's signals into the body. This Review will cover materials and devices designed for mimicking the skin's ability to sense and generate biomimetic signals.

  1. Concepts to optimize stent-grafting of abdominal aortic aneurysms based on results of experimental studies; Konzepte zur Optimierung der Stentgraftversorgung von Bauchaortenaneurysmen auf der Basis tierexperimenteller Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Chavan, A.; Kirchhoff, T.; Baus, S.; Galanski, M. [Medizinische Hochschule Hannover (Germany). Abt. Diagnostische Radiologie 1; Pichlmaier, M. [Medizinische Hochschule Hannover (Germany). Leibniz Forschungslab. fuer Biotechnologie und Kuenstliche Organe an der Klinik fuer Thorax-, Herz- und Gefaesschirurgie

    2001-08-01

    Purpose. In the endoluminal therapy of abdominal aortic aneurysms, a short proximal aneurysm neck, endoleaks and the large size and stiffness of the introducer systems are responsible for many of the complications and sub-optimal outcomes. The purpose of the present review article is to to suggest strategies to minimize these complications based on the results of experimental studies in animals. Material and methods. After implanting various types of stents across the renal artery origins, the functional and morphological changes in the kidneys and renal vessels were studied by various authors. In order to prevent progressive widening of the proximal aneurysmal neck and graft dislocation, Sonesson et al. performed a laparoscopic banding around the proximal neck in pigs. To study the effects of endoleaks, Marty, Schurink and Pitton carried out pressure measurements in experimental aneurysms with and without endoleaks. Sakaguchi and Pavcnik developed the 'Twin-tube endografts' (TTEG) and the 'Bifurcated drum occluder endografts' (BDOEG) and tested them in dogs. Results. Up to 3 months after suprarenal stent placement, Chavan et al. detected no significant fall in the mean inulin clearance in sheep (140{+-}46 ml/min before, 137{+-}58 ml/min after). Nasim et al. and Malina et al. reported similar observations with respect to renal function. Suprarenal fixation may result in isolated thrombotic occlusions of the renal arteries and microinfarcts in the kidneys. Mean aortic diameters at the level of banding were significantly smaller in the animals with aortic banding as opposed to those in the control group without banding (8 mm vs 11 mm, p=0.004). The banding caused a secure proximal fixation of the stent-graft. Persistent endoleaks resulted in significantly higher intraaneurysmal pressures. Although the TTEG and the BDOEG stent-grafts required smaller sheaths, occlusions were observed in 8% (TTEG) and 60% (BDOEG) of the graft limbs. (orig.) [German

  2. The effect of monomer molecular weight on grafting reaction

    International Nuclear Information System (INIS)

    Wu Minghong; Ding Zhongli; Ma Zueteh

    1995-01-01

    In this paper, some condensed ethylene glycol acrylate monomers with different molecular weight being grafted to the PE film by means of pre-irradiation is reported. The effect of molecular weight of monomer on grafting reaction and the hydrophilicity of grafting sample have been discussed. The experimental results show: molar degrees of grafting decreased non-linearly with the increasement of molecular weight of monomer, the grafting reaction of polymer is greater effected by the swelling degree of PE film, the greater the swelling degree of grafting material, the higher the grating degree grafting is, the initial rate of grafting reaction decreased with the increasement of molecular weight of monomer. (author)

  3. Which prosthetic foot to prescribe?

    OpenAIRE

    De Asha, AR; Barnett, CT; Struchkov, V; Buckley, JG

    2017-01-01

    Introduction: \\ud Clinicians typically use findings from cohort studies to objectively inform judgements regarding the potential (dis)advantages of prescribing a new prosthetic device. However, before finalising prescription a clinician will typically ask a patient to 'try out' a change of prosthetic device while the patient is at the clinic. Observed differences in gait when using the new device should be the result of the device’s mechanical function, but could also conceivably be due to pa...

  4. Animal experimental model of a graft-versus-host (GVH) reaction after allogenic transplantation of bone marrow in lethally irradiated mice

    International Nuclear Information System (INIS)

    Schwenke, H.; Muench, S.; Haubold, S.; Weber, B.

    1977-01-01

    The graft-versus-host (GVH) disease represents a serious still unsolved problem in the human allogenic transplantation of bone marrow. An experimental model of GVH reaction after an allogenic transplantation of bone marrow in the adult mouse has been worked out as a prerequisite for further studies on the therapeutic influence of this syndrome. 3 groups have been formed out of 82 lethally X-irradiated C57 Bl mice. The non-transplanted control group died to a hundred per cent within 12 days. While out of the 2nd group treated with syngenic bone marrow 55 per cent survived from the 22nd day, 30 per cent of the third animal group, allogenicly transplanted with histoincompatible AKR donor marrow developed a chronic GVH syndrome. The following symptoms were observed: retardation, alterations of the skin, diarrhea, edemas of the legs, failing increase of leukocytes in blood and proliferation of lymphocytes in bone marrow of about 60 per cent (18 per cent in syngenically transplanted animals), in lacking proliferation of hematopoiesis. The increase of liver and especially spleen index is not characteristic in comparison with the syngenically transplanted group, since in the latter there is also an increase of the values on account of a strong hematopoetic proliferation. The model is suitable and sufficiently well characterized for the performance of further experimental studies. (author)

  5. Prosthetic helping hand

    Science.gov (United States)

    Vest, Thomas W. (Inventor); Carden, James R. (Inventor); Norton, William E. (Inventor); Belcher, Jewell G. (Inventor)

    1992-01-01

    A prosthetic device for below-the-elbow amputees, having a C-shaped clamping mechanism for grasping cylindrical objects, is described. The clamping mechanism is pivotally mounted to a cuff that fits on the amputee's lower arm. The present invention is utilized by placing an arm that has been amputated below the elbow into the cuff. The clamping mechanism then serves as a hand whenever it becomes necessary for the amputee to grasp a cylindrical object such as a handle, a bar, a rod, etc. To grasp the cylindrical object, the object is jammed against the opening in the C-shaped spring, causing the spring to open, the object to pass to the center of the spring, and the spring to snap shut behind the object. Various sizes of clamping mechanisms can be provided and easily interchanged to accommodate a variety of diameters. With the extension that pivots and rotates, the clamping mechanism can be used in a variety of orientations. Thus, this invention provides the amputee with a clamping mechanism that can be used to perform a number of tasks.

  6. Marginal bone loss in implants placed in grafted maxillary sinus.

    Science.gov (United States)

    Galindo-Moreno, Pablo; Fernández-Jiménez, Andrés; O'Valle, Francisco; Silvestre, Francisco J; Sánchez-Fernández, Elena; Monje, Alberto; Catena, Andrés

    2015-04-01

    The purpose of this study is to evaluate the vertical and horizontal graft bone resorption (GR) in grafted maxillary sinuses and the marginal bone loss (MBL) around implants placed in the sinuses with different prosthetic connections and to determine the effect of other clinical factors on these tissue responses at 6 and 18 months postloading. A total of 254 implants were placed in 150 grafted maxillary sinuses of 101 patients (51.5% female) with mean age of 52.2 years (range, 32-82 years). GR and MBL measurements were made in implants placed with two different prosthetic connections (internal and external) at 6 and 18 months postloading. The complex samples general linear model was used to analyze the influence of patient age, gender, smoking habit, history of periodontal disease, implantation timing (simultaneous vs deferred), and prosthetic abutment length on radiographic GR and MBL values. At 18 months postloading, the MBL ranged from 0 mm to 5.89 mm; less than 1 mm was lost around 49.0% (mesial) and 44.3% (distal) of the implants, while no bone was lost around 32.9% (mesial) and 26.7% (distal). The GR was significantly affected by smoking, remnant alveolar bone height, graft length, graft height, gender, and age, and it significantly decreased over time. The MBL was influenced by the type of connection, implantation timing, and prosthetic abutment length. The MBL was greater with longer postloading interval and higher patient age and in smokers. Resorption of grafts that combine autogenous cortical bone with anorganic bovine bone is dependent on the anatomic features of the sinus and is not affected by the time elapsed after the first 6 months. The MBL in implants placed in these grafted areas is time dependent and mainly related to potentially modifiable clinical decisions and patient habits. © 2013 Wiley Periodicals, Inc.

  7. Does treatment of split-thickness skin grafts with negative-pressure wound therapy improve tissue markers of wound healing in a porcine experimental model?

    Science.gov (United States)

    Ward, Christopher; Ciraulo, David; Coulter, Michael; Desjardins, Steven; Liaw, Lucy; Peterson, Sarah

    2012-08-01

    Negative-pressure wound therapy (NPWT) has been used for to treat wounds for more than 15 years and, more recently, has been used to secure split-thickness skin grafts. There are some data to support this use of NPWT, but the actual mechanism by which NPWT speeds healing or improves skin graft take is not entirely known. The purpose of this project was to assess whether NPWT improved angiogenesis, wound healing, or graft survival when compared with traditional bolster dressings securing split-thickness skin grafts in a porcine model. We performed two split-thickness skin grafts on each of eight 30 kg Yorkshire pigs. We took graft biopsies on postoperative days 2, 4, 6, 8, and 10 and submitted the samples for immunohistochemical staining, as well as standard hematoxylin and eosin staining. We measured the degree of vascular ingrowth via immunohistochemical staining for von Willenbrand's factor to better identify blood vessel epithelium. We determined the mean cross-sectional area of blood vessels present for each representative specimen, and then compared the bolster and NPWT samples. We also assessed each graft for incorporation and survival at postoperative day 10. Our analysis of the data revealed that there was no statistically significant difference in the degree of vascular ingrowth as measured by mean cross-sectional capillary area (p = 0.23). We did not note any difference in graft survival or apparent incorporation on a macroscopic level, although standard hematoxylin and eosin staining indicated that microscopically, there seemed to be better subjective graft incorporation in the NPWT samples and a nonsignificant trend toward improved graft survival in the NPWT group. We were unable to demonstrate a significant difference in vessel ingrowth when comparing NPWT and traditional bolster methods for split-thickness skin graft fixation. More studies are needed to elucidate the manner by which NPWT exerts its effects and the true clinical magnitude of these

  8. Histologic and histomorphometric evaluation of bone regeneration using nanocrystalline hydroxyapatite and human freeze-dried bone graft : An experimental study in rabbit.

    Science.gov (United States)

    Sadeghi, Rokhsareh; Najafi, Mohammad; Semyari, Hassan; Mashhadiabbas, Fatemeh

    2017-03-01

    Bone regeneration is an important concern in periodontal treatment and implant dentistry. Different biomaterials and surgical techniques have been used for this purpose. The aim of the present study was to compare the effect of nanocrystalline hydroxyapatite and human freeze-dried bone graft (FDBG) in regeneration of rabbit calvarium bony defects by histologic and histomorphometric evaluation. In this experimental study, three similar defects, measuring 8 mm in diameter, were created in the calvaria of 16 white New Zealand rabbits. Two defects were filled with FDBG and nanocrystalline hydroxyapatite silica gel, while the other one remained unfilled to be considered as control. All the defects were covered with collagen membranes. During the healing period, two animals perished; so 14 rabbits were divided into two groups: half of them were euthanized after 6 weeks of healing and the other half after 12 weeks. The specimens were subjected to histologic and histomorphometric examinations for assessment of the following variables: percentage of bone formation and residual graft material, inflammation scores, patterns of bone formation and type of newly formed bone. The percentages of new bone formation after 6 weeks were 14.22 ± 7.85, 21.57 ± 6.91, and 20.54 ± 10.07% in FDBG, NanoBone, and control defects. These values were 27.54 ± 20.19, 23.86 ± 6.27, and 26.48 ± 14.18% in 12-week specimens, respectively. No significant differences were found in the amount of bone formation between the groups. With regard to inflammation, the control and NanoBone groups showed significantly less inflammation compared to FDBG at the 6-week healing phase (P = 0.04); this difference was not significant in the 12-week specimens. Based on the results of this experimental study, both NanoBone and FDBG exhibited a similar effect on bone formation.

  9. 100 top-cited scientific papers in limb prosthetics.

    Science.gov (United States)

    Eshraghi, Arezoo; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq; Shadgan, Babak

    2013-11-17

    Research has tremendously contributed to the developments in both practical and fundamental aspects of limb prosthetics. These advancements are reflected in scientific articles, particularly in the most cited papers. This article aimed to identify the 100 top-cited articles in the field of limb prosthetics and to investigate their main characteristics. Articles related to the field of limb prosthetics and published in the Web of Knowledge database of the Institute for Scientific Information (ISI) from the period of 1980 to 2012. The 100 most cited articles in limb prosthetics were selected based on the citation index report. All types of articles except for proceedings and letters were included in the study. The study design and level of evidence were determined using Sackett's initial rules of evidence. The level of evidence was categorized either as a systematic review or meta-analysis, randomized controlled trial, cohort study, case-control study, case series, expert opinion, or design and development. The top cited articles in prosthetics were published from 1980 to 2012 with a citation range of 11 to 90 times since publication. The mean citation rate was 24.43 (SD 16.7) times. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) and case series studies (67%) that used human subjects (96%) providing level 4 evidence. Among the various fields, rehabilitation (47%), orthopedics (29%), and sport sciences (28%) were the most common fields of study. The study established that studies conducted in North America and were written in English had the highest citations. Top cited articles primarily dealt with lower limb prosthetics, specifically, on transtibial and transradial prosthetic limbs. Majority of the articles were experimental studies.

  10. Investigating the uncanny valley for prosthetic hands.

    Science.gov (United States)

    Poliakoff, Ellen; O'Kane, Sophie; Carefoot, Olivia; Kyberd, Peter; Gowen, Emma

    2018-02-01

    In 1970, Mori hypothesised the existence of an 'uncanny valley', whereby stimuli falling short of being fully human are found to be creepy or eerie. To investigate how eerie people find different prosthetic hands and whether perceptions of eeriness can be accounted for by categorical ambiguity. Students participated in computerised experiments during which photographic images of hands were presented. We compared photographs of prosthetic hands pre-selected as more (H+) or less human-like (H-), as well as mechanical and real hands. Participants rated the hands for eeriness and human-likeness, as well as performing a speeded classification (human/non-human) and location judgment (control) task. The H- prosthetic hands were rated as more eerie than the H+ prosthetic, mechanical and real hands, and this was unaffected by hand orientation. Participants were significantly slower to categorise the H+ prosthetic hands compared to the H- prosthetic and real hands, which was not due to generally slower responses to the H+ prosthetic hands (control task). People find prosthetic hands to be eerie, most consistently for less human-like prosthetic hands. This effect is not driven by ambiguity about whether to categorise the prosthetic hand as human or artificial. Clinical relevance More obviously artificial, less-realistic, prosthetic hands consistently generate a sense of eeriness, while more realistic prosthetic hands avoid the uncanny valley, at least on initial viewing. Thus, greater realism in prosthetic design may not always incur a cost, although the role of movement and cutaneous input requires further investigation.

  11. Holographic methods for quality monitoring and stress visualization in biological and mechanical prosthetic heart valves

    Science.gov (United States)

    Zarubin, Alexander M.; von Bally, Gert; Deiwick, M.; Geiger, A. W.; Scheld, H. H.

    1996-01-01

    A new application of holographic interferometry in biomedicine and bioengineering is presented. Holographic interferometry techniques for non-destructive testing and biomechanical evaluation of prosthetic heart valves are developed, and experimental results obtained with tissue and mechanical values are demonstrated.

  12. Candida infection of a prosthetic shoulder joint

    International Nuclear Information System (INIS)

    Lichtman, E.A.; Veterans Administration Medical Center, New York

    1983-01-01

    A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole. (orig.)

  13. Validation of the prosthetic esthetic index

    DEFF Research Database (Denmark)

    Özhayat, Esben B; Dannemand, Katrine

    2014-01-01

    OBJECTIVES: In order to diagnose impaired esthetics and evaluate treatments for these, it is crucial to evaluate all aspects of oral and prosthetic esthetics. No professionally administered index currently exists that sufficiently encompasses comprehensive prosthetic esthetics. This study aimed...

  14. Candida infection of a prosthetic shoulder joint

    Energy Technology Data Exchange (ETDEWEB)

    Lichtman, E.A.

    1983-09-01

    A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole.

  15. Prosthetic management of deciduous teeth

    OpenAIRE

    Bassil, Jean

    2015-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária Introduction: Situations of single or multiple edentulous are not an exception during childhood. Prosthetic management is necessary in case of absence of replacing tooth or when its eruption is planned too far in time. Indications of prosthetic rehabilitation for children are multiple and rise from the etiologic factors caus...

  16. Calcification of a Synthetic Renovascular Graft in a Child

    Directory of Open Access Journals (Sweden)

    D.S.T. Chong

    Full Text Available : Introduction: Vascular grafts, especially in paediatric cases, need to be durable. Common failures such as thrombosis are well documented with research efforts directed towards them. However, there are lesser known causes of graft failure, such as graft calcification, and these also require further research focus. Report: A paediatric case is described in which a synthetic renovascular graft, implanted for mid-aortic syndrome, became calcified, necessitating surgical intervention to resolve graft malfunction. Significant calcification in the limb of a bifurcated polyethylene terephthalate graft was found to be the cause of resistant stenosis and refractory hypertension. Histology conducted on the explanted limb showed the presence of multinuclear giant cells, indicating a chronic foreign body response. Discussion: Calcification of vascular grafts is probably more common than previously recognised. Stenosis typically resistant to angioplasty may result in the long term and thus leading to surgical intervention. In young children, this is suboptimal as these grafts need to last throughout adulthood. Explanted prosthetic grafts should be sent to specialist registries such as that in Strasbourg to be optimally assessed so that contributory factors can be identified. Keywords: Renovascular graft, Paediatric, Calcification

  17. Prosthetic Rehabilitation After Hip Disarticulation or Hemipelvectomy.

    Science.gov (United States)

    Kralovec, Michael E; Houdek, Matthew T; Andrews, Karen L; Shives, Thomas C; Rose, Peter S; Sim, Franklin H

    2015-12-01

    Prosthetic rehabilitation after pelvic-level amputation (hemipelvectomy/hip disarticulation) is difficult, and because of this, many patients are never fit with a prosthetic limb. The objectives of the study were to evaluate the characteristics of successful prosthetic users and to determine what factors are associated with successful prosthetic fitting and use. The authors identified 43 patients who underwent hip disarticulation/hemipelvectomy between 2000 and 2010 and were candidates for prosthetic fitting at the authors' institution. The medical records of these patients were then reviewed for pertinent demographic and medical characteristics to identify the profile of successful prosthetic users. Of 43 patients, 18 (43%) successfully used a prosthetic limb. The only preoperative factor associated with unsuccessful prosthetic fitting was coronary artery disease. Specifically, age, body mass index, other medical comorbidities, and demographic characteristics were not associated with successful or unsuccessful prosthetic fitting. Successful users wore their prosthesis an average of 5.8 hrs/day, and most ambulated with one or both hands free. Successful prosthetic rehabilitation after hemipelvectomy and hip disarticulation is possible. Increased body mass index, advanced age, depression, and other comorbidities should not discourage prosthetic rehabilitation. Most patients that undergo prosthetic rehabilitation enjoy long periods of survival and wear their prosthesis for most of the day.

  18. Target of physiological gait: Realization of speed adaptive control for a prosthetic knee during swing flexion.

    Science.gov (United States)

    Cao, Wujing; Yu, Hongliu; Zhao, Weiliang; Li, Jin; Wei, Xiaodong

    2017-10-13

    Prosthetic knee is the most important component of lower limb prosthesis. Speed adaptive for prosthetic knee during swing flexion is the key method to realize physiological gait. This study aims to discuss the target of physiological gait, propose a speed adaptive control method during swing flexion and research the damping adjustment law of intelligent hydraulic prosthetic knee. According to the physiological gait trials of healthy people, the control target during swing flexion is defined. A new prosthetic knee with fuzzy logical control during swing flexion is designed to realize the damping adjustment automatically. The function simulation and evaluation system of intelligent knee prosthesis is provided. Speed adaptive control test of the intelligent prosthetic knee in different velocities are researched. The maximum swing flexion of the knee angle is set between sixty degree and seventy degree as the target of physiological gait. Preliminary experimental results demonstrate that the prosthetic knee with fuzzy logical control is able to realize physiological gait under different speeds. The faster the walking, the bigger the valve closure percentage of the hydraulic prosthetic knee. The proposed fuzzy logical control strategy and intelligent hydraulic prosthetic knee are effective for the amputee to achieve physiological gait.

  19. Control method for prosthetic devices

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor)

    1995-01-01

    A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the moveable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the moveable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective moveable prosthesis device and its sub-prosthesis.

  20. Stent graft placement for dysfunctional arteriovenous grafts

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  1. A heparin-bonded vascular graft generates no systemic effect on markers of hemostasis activation or detectable heparin-induced thrombocytopeniaassociated antibodies in humans

    NARCIS (Netherlands)

    Heyligers, Jan M. M.; Lisman, Ton; Verhagen, Hence J. M.; Weeterings, Cees; de Groot, Philip G.; Moll, Frans L.

    Objectives. Almost a third of patients who undergo peripheral bypass procedures do not have suitable veins, making the use of prosthetic materials necessary. Prosthetic materials can cause platelet adhesion and activation of the coagulation cascade on the graft. One potential strategy to reduce this

  2. Dimensional evaluation of blood clot gap distances within the intrabony defects following grafting and EDTA root surface treatment - experimental study in dogs.

    Science.gov (United States)

    Gamal, Ahmed Y; Abdel-Ghaffar, Khaled A; Zouair, Mohamed G; Salama, Mohamed H; Destawy, Mahmoud T El

    2018-03-14

    Since it is important to establish and maintain a firm blood clot to the surrounding tissues within the intrabony lesion; we have to investigate the potentials of different materials in resisting clot retraction that disrupt clot adhesion to the root surface. This study was designed to measure the gap distance created by clot retraction within the defect following intrabony defects grafting with and without root surface EDTA etching. Eight mongrel dogs with surgically created acute-chronic bilateral mandibular interproximal intrabony defects in the premolar-molar areas were enrolled in this study (total 8 defects per dog). Intrabony defects were divided into four groups, the first group (OFD): control open flap debridement, the second group, (EDTA treated defects) in which debridement of the defects was followed by two minute root surface etching with a neutral 24% EDTA gel followed by two minute copious saline irrigation, the third group (only grafted defects): defects received closely packed β-TCP of a particle size ranged from 150 to 500 mm, and the fourth group, (Graft + EDTA treated defects): defects were etched for 2 minutes with a neutral 24% EDTA gel and saline irrigation followed by intrabony defect fill of β-TCP. Twenty four hours post treatment, animal euthanasia was carried out for histomorphometric analysis of the tooth and root side gap distances. EDTA treated group and EDTA + graft group showed statistically significant lower degree of clot shrinkage compared to both the control and only grafted group. Clot shrinkage in EDTA treated group showed no significant difference from that of the EDTA + graft group (p = 0.197). OFD and only grafted groups were found to show statistically higher clot retraction percnetage compared to both EDTA and EDTA+graft groups. following intrabony defect debridement, blood clot undergoes clot retraction creating a micro gap with the root surface. EDTA root surface etching before graft application into the defect area

  3. Fifteen years of follow-up of a removable prosthetic design to maintain two remaining molars in a patient with mandibular reconstruction

    Directory of Open Access Journals (Sweden)

    Ming-Lun Hsu

    2012-06-01

    Full Text Available This clinical report describes a long-term prosthetic solution for a patient who had undergone mandibular reconstruction with a fibular graft, leaving only two right molars. The only retention device for the removable prosthesis design included a telescoping system with an O-ring application, but without fibula graft involvement. This prosthesis design was motivated by the altered bony and muscular architecture resulting in an increased maxillomandibular space and thick soft tissue in the denture-bearing area. This case demonstrates that appropriate denture design, consistent recall maintenance, and oral hygiene motivation minimized periodontal destruction and maximized prosthetic use for the patient despite the unfavorable loading conditions.

  4. Dilatation of aortic grafts over time: what to expect and when to be concerned

    DEFF Research Database (Denmark)

    Schroeder, Torben V; Eldrup, Nikolaj; Just, Sven

    2009-01-01

    insertion of a woven polyester or expanded polytetrafluoroethylene (ePTFE) graft. Patients were followed with computed tomography and ultrasonography for up to 5 years in order to assess the frequency and magnitude of postoperative dilatation. Graft dilatation was documented in patients with polyester...... grafts at 12 months. Thereafter and up to 60 months, polyester grafts did not dilate further. After 5 years, polyester prostheses had dilated by 25% and ePTFE by 12.5%, as determined by computed tomography imaging. These observations suggest that dilatation of prosthetic grafts is more frequent...... with knitted polyester grafts compared with ePTFE. Dilatation occurs within the first year after implantation and can be, in part, explained by a discrepancy between the initial nominal graft diameter and its diameter after clamp release, probably due to an in vivo adaptation of the textile structure...

  5. [Preventive strategies in prosthetic dentistry].

    Science.gov (United States)

    Kern, M; Böning, K W; Stark, H; Wolowski, A; Wöstmann, B; Walter, M H

    2011-09-01

    Despite the success in preventing oral diseases, the prevalence of tooth loss in the German population remains high and increases with age. Today, the advances in prosthetic dentistry allow necessary tooth replacement following preventive strategies-after considering benefits and risks. Modern treatment options improve the overall prognosis of the stomatognathic system and the quality of life of the affected patients significantly. Hereby, adverse iatrogenic effects can be minimized or even completely avoided by extending the traditional treatment spectrum, e.g., using adhesively fixed restorations and implant-supported restorations, and refraining from placing restorations that are unnecessary from the medical point of view. Generally, patients benefit greatly from prosthetic treatment and the achieved health gain is remarkably high. It encompasses not only the recovery of the impaired oral functions but also extends to the whole human organism, including nutrition, digestion, musculoskeletal system, as well as mental and social well-being.

  6. Kytococcus schroeteri prosthetic valve endocarditis

    OpenAIRE

    Yousri, Taher; Hawari, Mohammad; Saad, Rasheed; Langley, Steve

    2010-01-01

    We report the case of a 64-year-old male patient with a prosthetic aortic valve who presented with clinical features of endocarditis confirmed by transoesophageal echocardiography. His blood cultures were positive for a very rare and newly described organism—Kytococcus schroeteri. The patient underwent aortic valve replacement and a 6-week course of intravenous antibiotics. This is the fifth reported case of endocarditis associated with this organism.

  7. Kytococcus schroeteri prosthetic valve endocarditis.

    Science.gov (United States)

    Yousri, Taher; Hawari, Mohammad; Saad, Rasheed; Langley, Steve

    2010-09-29

    We report the case of a 64-year-old male patient with a prosthetic aortic valve who presented with clinical features of endocarditis confirmed by transoesophageal echocardiography. His blood cultures were positive for a very rare and newly described organism-Kytococcus schroeteri. The patient underwent aortic valve replacement and a 6-week course of intravenous antibiotics. This is the fifth reported case of endocarditis associated with this organism.

  8. Control System for Prosthetic Devices

    Science.gov (United States)

    Bozeman, Richard J. (Inventor)

    1996-01-01

    A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that of movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the moveable body part through the full-shrg position of the moveable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the moveable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective moveable prosthesis device and its sub-prosthesis.

  9. Bar-holding prosthetic limb

    Science.gov (United States)

    Vest, Thomas W. (Inventor); Norton, William E. (Inventor); Belcher, Jewell G. (Inventor); Carden, James R. (Inventor)

    1992-01-01

    A prosthetic device for below-the-elbow amputees is disclosed. The device has a removable effector, which is attached to the end of an arm cuff. The effector is comprised of a pair of C-shaped members that are oriented so as to face each other. Working in concert, the C-shaped members are able to hold a bar such as a chainsaw handle. A flat spring is fitted around the C-shaped members to hold them together.

  10. Computer Aided Facial Prosthetics Manufacturing System

    Directory of Open Access Journals (Sweden)

    Peng H.K.

    2016-01-01

    Full Text Available Facial deformities can impose burden to the patient. There are many solutions for facial deformities such as plastic surgery and facial prosthetics. However, current fabrication method of facial prosthetics is high-cost and time consuming. This study aimed to identify a new method to construct a customized facial prosthetic. A 3D scanner, computer software and 3D printer were used in this study. Results showed that the new developed method can be used to produce a customized facial prosthetics. The advantages of the developed method over the conventional process are low cost, reduce waste of material and pollution in order to meet the green concept.

  11. Distal anastomotic vein adjunct usage in infrainguinal prosthetic bypasses.

    Science.gov (United States)

    McPhee, James T; Goodney, Philip P; Schanzer, Andres; Shaykevich, Shimon; Belkin, Michael; Menard, Matthew T

    2013-04-01

    Single-segment saphenous vein remains the optimal conduit for infrainguinal revascularization. In its absence, prosthetic conduit may be used. Existing data regarding the significance of anastomotic distal vein adjunct (DVA) usage with prosthetic grafts are based on small series. This is a retrospective cohort analysis derived from the regional Vascular Study Group of New England as well as the Brigham and Women's hospital database. A total of 1018 infrainguinal prosthetic bypass grafts were captured in the dataset from 73 surgeons at 15 participating institutions. Propensity scoring and 3:1 matching was performed to create similar exposure groups for analysis. Outcome measures of interest included: primary patency, freedom from major adverse limb events (MALEs), and amputation free survival at 1 year as a function of vein patch utilization. Time to event data were compared with the log-rank test; multivariable Cox proportional hazard models were used to evaluate the adjusted association between vein cuff usage and the primary end points. DVA was defined as a vein patch, cuff, or boot in any configuration. Of the 1018 bypass operations, 94 (9.2%) had a DVA whereas 924 (90.8%) did not (no DVA). After propensity score matching, 88 DVAs (25%) and 264 no DVAs (75%) were analyzed. On univariate analysis of the matched cohort, the DVA and no DVA groups were similar in terms of mean age (70.0 vs 69.0; P = .55), male sex (58.0% vs 58.3%; P > .99), and preoperative characteristics such as living at home (93.2% vs 94.3%; P = .79) and independent ambulatory status (72.7% vs 75.7%; P = .64). The DVA and no DVA groups had similar rates of major comorbidities such as hypertension chronic obstructive pulmonary disease, diabetes mellitus, coronary artery disease, and dialysis dependence (P > .05 for all). Likewise, they had similar rates of distal origin grafts (13.6% vs 12.5%; P = .85), critical limb ischemia indications (P = .53), and prior arterial bypass (58% vs 47%; P = .08

  12. Fifteen years of follow-up of a removable prosthetic design to maintain two remaining molars in a patient with mandibular reconstruction

    OpenAIRE

    Ming-Lun Hsu; Jacqueline Chia-Hsuan Wu; Ling-Ming Yu

    2012-01-01

    This clinical report describes a long-term prosthetic solution for a patient who had undergone mandibular reconstruction with a fibular graft, leaving only two right molars. The only retention device for the removable prosthesis design included a telescoping system with an O-ring application, but without fibula graft involvement. This prosthesis design was motivated by the altered bony and muscular architecture resulting in an increased maxillomandibular space and thick soft tissue in the den...

  13. Distal vein patch use and limb events after infragenicular prosthetic bypasses.

    Science.gov (United States)

    Branco, Bernardino C; Kougias, Panos; Braun, Jonathan D; Mills, Joseph L; Barshes, Neal R

    2018-02-10

    In the absence of suitable autologous vein, the use of prosthetic grafts for infragenicular bypasses in peripheral arterial disease has become standard practice. The purpose of this study was to investigate whether creating a vein patch at the distal anastomosis would further improve patency and freedom from major adverse limb events (MALEs). Furthermore, we sought to investigate whether the use of a distal vein patch (DVP) was associated with lower rates of acute limb ischemia (ALI) for those presenting with occluded prosthetic bypass graft. The cases of all patients undergoing infragenicular prosthetic bypass grafts between January 2009 and July 2016 were retrospectively reviewed. Demographics of the patients, clinical data, and outcomes (graft patency and MALEs) were collected. Patients were compared according to treatment group (DVP vs no DVP). A Cox regression analysis was used to analyze follow-up results. During the study period, a total of 373 patients underwent infragenicular bypass at our institution; of those, 93 (24.9%) had prosthetic grafts (DVP, 39; no DVP, 54). Overall, 92 (98.9%) patients were male; the mean age was 63.3 ± 6.6 years and did not differ between the two groups. Patients undergoing prosthetic bypass with DVP were more likely to have chronic obstructive pulmonary disease (38.5% vs 14.8%; P = .009) and less likely to have chronic kidney disease (2.6% vs 20.4%; P = .011). Follow-up data were available for all patients for a median of 7.8 months (range, 1-89 months). After adjustment for differences in demographics and clinical data between the two groups, when outcomes were analyzed, MALEs were significantly lower in the DVP group (35.9% vs 57.4%; odds ratio [OR], 0.4; 95% confidence interval [CI], 0.2-0.9; P = .041). Similarly, reintervention rates were significantly lower in the DVP group (30.8% vs 50.0%; OR, 0.4; 95% CI, 0.2-0.9; P = .044). There was a trend toward higher primary patency in the DVP group (46.2% vs 35.2%; OR, 1

  14. Novel Materials for Prosthetic Liners

    Science.gov (United States)

    Ragolta, Carolina I.; Morford, Megan

    2011-01-01

    Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury that reduce quality of life. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications. Three tests were performed on several types of aerogel to assess the properties of each material. Moisture vapor permeability was tested by incubating four aerogel varieties with an artificial sweat solution at 37.0 C and less than 20% relative humidity for 24 hours. Two aerogel varieties were eliminated from the study due to difficulties in handling the material, and further testing proceeded with Pyrogel in 2.0 and 6.0 mm thicknesses. Force distribution was tested by compressing samples under a load of 4448 N at a rate of 2.5 mm/min. Biofilm formation was tested in a high-shear CDC Biofilm Reactor. Results showed that 2.0 mm Pyrogel blanket allowed 55.7 plus or minus 28.7% of an artificial sweat solution to transpire, and 35.5 plus or minus 27.8% transpired through 6.0 mm Pyrogel blanket. Samples also outperformed the load-bearing capabilities of existing liner materials. No statistically significant difference was found between the two Pyrogel thicknesses for either moisture vapor permeability or force distribution. In addition, biofilm formation results showed no change between the two Pyrogel thicknesses. The breathability and load bearing properties of aerogel make it a suitable material for application to prosthetic liners.

  15. [Facial prosthetics: grounds and techniques].

    Science.gov (United States)

    Dirven, R; Lieben, G; Bouwman, S; Wolterink, R; van den Brekel, M W M; Lohuis, P J F M

    2017-09-01

    Surgical treatment of advanced facial tumours is often physically, functionally and emotionally debilitating. The resulting defects often give grounds for surgical reconstruction, prosthetic reconstruction or a combination of both. During the past two decades, huge advances have been achieved in the development of prostheses. This has led to improved rehabilitation of facial defects. In the clinic of the Netherlands Cancer Institute - Antoni van Leeuwenhoek, both adhesive- and implant-retained facial prostheses are used. In recent decades, implant-retained prostheses have been used increasingly often. Patient satisfaction rates are very high for both types of prostheses.

  16. State of the Art: Amputation and Prosthetics.

    Science.gov (United States)

    Westberry, David E

    2017-09-01

    Amputation is not a defeat or failure of treatment, but an effective management strategy for certain conditions in the pediatric population. The principles of management, especially in the pediatric population, have not changed. Current surgical strategies focus on providing an optimal residual limb for prosthetic fitting. New technology provides improvement in the design and fabrication of prosthetic devices.

  17. Designing prosthetic knee joints with bio-inspired bearing surfaces.

    Science.gov (United States)

    Qiu, Mingfeng; Chyr, Anthony; Sanders, Anthony P; Raeymaekers, Bart

    2014-09-01

    It has long been known that articular cartilage exhibits a surface microtexture with shallow indentations. By contrast, prosthetic joints consist of ultra-smooth bearing surfaces, the longevity of which does not reach that of natural cartilage. We show that adding a microtexture to the smooth femoral component of a prosthetic knee joint reduces friction by increasing the lubricant film thickness between the bearing surfaces of the knee. We have implemented an elastohydrodynamic lubrication model to optimize the geometry of the microtexture, while taking into account the deformation of the polyethylene tibial insert. We have manufactured several microtexture designs on a surrogate femoral component, and experimentally demonstrate that the microtexture reduces friction between the surrogate femoral component and tibial insert.

  18. Cochlear Implant Using Neural Prosthetics

    Science.gov (United States)

    Gupta, Shweta; Singh, Shashi kumar; Dubey, Pratik Kumar

    2012-10-01

    This research is based on neural prosthetic device. The oldest and most widely used of these electrical, and often computerized, devices is the cochlear implant, which has provided hearing to thousands of congenitally deaf people in this country. Recently, the use of the cochlear implant is expanding to the elderly, who frequently suffer major hearing loss. More cutting edge are artificial retinas, which are helping dozens of blind people see, and ìsmartî artificial arms and legs that amputees can maneuver by thoughts alone, and that feel more like real limbs.Research, which curiosity led to explore frog legs dancing during thunderstorms, a snail shapedorgan in the inner ear, and how various eye cells react to light, have fostered an understanding of how to ìtalkî to the nervous system. That understanding combined with the miniaturization of electronics and enhanced computer processing has enabled prosthetic devices that often can bridge the gap in nerve signaling that is caused by disease or injury.

  19. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

    Full Text Available Bone grafting is the process by which bone is transferred from a source (donor to site (recipient. Due to trauma from accidents by speedy vehicles, falling down from height or gunshot injury particularly in human being, acquired or developmental diseases like rickets, congenital defects like abnormal bone development, wearing out because of age and overuse; lead to bone loss and to replace the loss we need the bone grafting. Osteogenesis, osteoinduction, osteoconduction, mechanical supports are the four basic mechanisms of bone graft. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. An ideal bone graft material is biologically inert, source of osteogenic, act as a mechanical support, readily available, easily adaptable in terms of size, shape, length and replaced by the host bone. Except blood, bone is grafted with greater frequency. Bone graft indicated for variety of orthopedic abnormalities, comminuted fractures, delayed unions, non-unions, arthrodesis and osteomyelitis. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. By adopting different procedure of graft preservation its antigenicity can be minimized. The concept of bone banking for obtaining bone grafts and implants is very useful for clinical application. Absolute stability require for successful incorporation. Ideal bone graft must possess osteogenic, osteoinductive and osteocon-ductive properties. Cancellous bone graft is superior to cortical bone graft. Usually autologous cancellous bone graft are used as fresh grafts where as allografts are employed as an alloimplant. None of the available type of bone grafts possesses all these properties therefore, a single type of graft cannot be recomm-ended for all types of orthopedic abnormalities. Bone grafts and implants can be selected as per clinical problems, the equipments available and preference of

  20. Prosthetic

    Directory of Open Access Journals (Sweden)

    Pokpong Amornvit

    2014-01-01

    Full Text Available Ocular trauma can be caused by road traffic accidents, falls, assaults, or work-related accidents. Enucleation is often indicated after ocular injury or for the treatment of intraocular tumors, severe ocular infections, and painful blind eyes. Rehabilitation of an enucleated socket without an intraocular implant or with an inappropriately sized implant can result in superior sulcus deepening, enophthalmos, ptosis, ectropion, and lower lid laxity, which are collectively known as post-enucleation socket syndrome. This clinical report describes the rehabilitation of post-enucleation socket syndrome with a modified ocular prosthesis. Modifications to the ocular prosthesis were performed to correct the ptosis, superior sulcus deepening, and enophthalmos. The rehabilitation procedure produced satisfactory results.

  1. Fully 3-dimensional digitally planned reconstruction of a mandible with a free vascularized fibula and immediate placement of an implant-supported prosthetic construction

    NARCIS (Netherlands)

    Schepers, Rutger H.; Raghoebar, Gerry M.; Vissink, Arjan; Lahoda, Lars U.; Van der Meer, W. Joerd; Roodenburg, Jan L.; Reintsema, Harry; Witjes, Max J.

    Background Reconstruction of craniofacial defects becomes complex when dental implants are included for functional rehabilitation. We describe a fully 3-dimensional (3D) digitally planned reconstruction of a mandible and immediate prosthetic loading with a fibula graft in a 2-step surgical approach.

  2. Sinus Floor Augmentation Comparing an In Situ Hardening Biphasic Calcium Phosphate (Hydroxyapatite/β-Tricalcium Phosphate) Bone Graft Substitute with a Particulate Biphasic Calcium Phosphate (Hydroxyapatite/β-Tricalcium Phosphate) Bone Graft Substitute: An Experimental Study in Sheep.

    Science.gov (United States)

    Wildburger, Angelika; Bubalo, Vladimir; Magyar, Marton; Nagursky, Heiner; Jakse, Norbert; Schmelzeisen, Rainer; Sauerbier, Sebastian

    2017-07-01

    The aim of the present split-mouth study in sheep was to assess the influence of in situ hardening properties of a biphasic calcium phosphate (BCP) bone graft substitute (BGS) (ratio hydroxyapatite/β-tricalcium phosphate = 60/40) compared with a particulate BGS with the same biphasic core-granule composition without in situ hardening properties on sinus floor augmentation. Therefore, bilateral sinus floor augmentation was performed in eight sheep. Poly(lactide-co-glycolide) (PLGA)-coated, in situ hardening biphasic BGS (PLGA-NMP [N-Methyl-2-pyrrolidone]-BCP) was placed at the test site, and a particulate biphasic BGS without PLGA coating (BCP) was used for the contralateral site as a control. Animals were sacrificed after 21 weeks. Sinus augmentation sites were analyzed histologically. The volume was analyzed by computed tomography. Histomorphometric parameters were assessed for the 12 and 21 weeks' time points. Slopes of new bone formation over time were compared with a linear growth regression model. Bone formation after 12 and 21 weeks of healing was 8.94% (±3.74) and 19.82% (±6.29) for PLGA-NMP-BCP and 7.00% (±2.58) and 14.38% (±4.51) for BCP, respectively. The bone growth rate for PLGA-NMP-BCP was higher than the growth rate for BCP (probability 97.5%). The total fraction of calcified hard tissue (% bone fraction + % biomaterial) was around 46% for both tested biomaterials, 21 weeks after sinus floor augmentation. The in situ hardening BGS (PLGA-NMP-BCP) performed better than the particulate material (BCP) in terms of bone formation rate. The in situ hardening properties of the PLGA-NMP-BCP material mediated by the PLGA coating and NMP solution as plasticizer had no negative influence on the bone formation.

  3. Determination of the distribution of graft yields following a radiation-induced graft copolymerization

    International Nuclear Information System (INIS)

    Schipschack, K.; Wagner, H.; Sawtschenko, L.

    1976-01-01

    In the radiation-induced graft copolymerization on solid initial polymers a distribution of graft yields takes place along the cross-sections of samples. Methods for determining this distribution, which are described in the literature, are reviewed. In our own investigations boards made of ethylene-vinyl acetate copolymers and grafted with vinyl chloride were used. Distributions of the grafted component obtained by infrared analysis of microtome cuts parallel to the surface are partly rather inhomogeneous, and are interpreted as dependent on the experimental parameters. (author)

  4. Computed tomography evaluation of autogenous graft in sinus lift surgery

    International Nuclear Information System (INIS)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro; Alves, Maria Teresa de Seixas

    2001-01-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  5. Utilização da veia glicerolada na regeneração neural: Estudo experimental em ratos The use of glycerol-treated venous graft in damaged nerves repair: an experimental study in rats

    Directory of Open Access Journals (Sweden)

    Armando dos Santos Cunha

    2007-01-01

    Full Text Available A auto-enxertia de nervo é o tratamento de escolha para grandes perdas de tecido neural que não podem ser reparadas por meio de rafia primária. A utilização do enxerto venoso previamente conservado em glicerol seria uma alternativa para diminuir o tempo operatório e a morbidade cirúrgica nesses casos. Os vasos preservados em glicerol não apresentam destruição de sua estrutura, o que permite seu uso na microcirurgia vascular, tendo a vantagem de diminuir a imunogenicidade do enxerto. O objetivo deste trabalho experimental foi comparar o grau de reparação nervosa, utilizando análise histológica, contagem do número de axônios mielinizados regenerados e análise funcional, obtida com a interposição de enxerto autógeno (grupo A e de tubo de veia glicerolada (grupo B em defeitos de 5 mm no nervo fibular de ratos Wistar. Somente no grupo A foi observado a formação de neuroma. O grupo B apresentou padrões histológicos compatíveis com diminuição quantitativa do número de axônios mielinizados regenerados em menor número em relação ao grupo A (controle. Na recuperação funcional, não houve diferença estatisticamente significativa entre os dois grupos.Autografting is the treatment of choice for cases of major nervous tissue loss where the ruptured nerve ends cannot be reduced. The use of a venous autograft previously treated with glycerol may be an alternative treatment, as it reduces surgery time duration and level of morbidity. Blood vessel explants, used in vascular microsurgery, kept in glycerol maintain their original biological structure, and when used in autografting, present reduced levels of patient's immune response. The aim of this study was to compare the level of nervous tissue regeneration by using histological analysis, regenerated myelinized axons counts, and functional analysis, obtained with the interposition of autologous graft (group A and glycerol-treated vein tube (group B in 5-mm defects on Wistar

  6. A Novel Technique of Fabricating a Modified Removable Provisional Prosthesis over an Autologous Bone Grafted Maxillary Anterior Edentulous Segment Prior to Implant Placement

    OpenAIRE

    Andonissamy, Leoney; Vidhya, N. Sri

    2017-01-01

    Implant dentistry has provided a lot of surgical as well as prosthetic techniques for improving the success of the implants. The surgical technique commonly followed now prior to implant placement is bone grafting procedure. One of the commonest techniques is the use of autologous block graft harvested from mandibular chin region. However, interference in healing as well as excessive bone resorption due to the use of removable provisional prosthesis over the bone grafted region has been commo...

  7. Scrotal reconstruction and testicular prosthetics.

    Science.gov (United States)

    Lucas, Jacob W; Lester, Kyle M; Chen, Andrew; Simhan, Jay

    2017-08-01

    Scrotal surgery encompasses a wide-variety of surgical techniques for an even wider variety of indications. In this manuscript, we review our indications, techniques, and pit-falls for various reconstructive scrotal surgeries as-well-as surgical tips for placement of testicular prostheses. Penoscrotal webbing (PSW) is an abnormal, often-problematic distal insertion of scrotal skin onto the ventral penile shaft. There are several effective and straightforward techniques used to revise this condition, which include simple scrotoplasty, single- or double-Z-plasty, or the VY-flap scrotoplasty. Reconstruction is also commonly indicated following scrotal skin loss caused by infection, trauma, lymphedema, hidradenitis, and cancer. Although initial management of these conditions often involves scrotal skin removal, repair of expansive scrotal skin loss can be technically difficult and can be accomplished by using one of several skin flaps or skin grafting. Split-thickness skin grafting of scrotal defects can be accomplished easily, and provides durable results.

  8. Effects of a flat prosthetic foot rocker section on balance and mobility.

    Science.gov (United States)

    Hansen, Andrew; Nickel, Eric; Medvec, Joseph; Brielmaier, Steven; Pike, Alvin; Weber, Marilyn

    2014-01-01

    Previous studies have shown that the effective rocker shape of the physiologic ankle-foot system during standing and fore-aft swaying is much flatter than that used during walking, which indicates a more stable base of support for the standing/swaying activity. Previous work suggests that flat regions within the effective rocker shapes of prosthetic ankle-foot systems could provide enhanced stability for standing balance tasks. An experimental prosthetic foot was altered to provide three different flat region lengths within its effective rocker shape. It was hypothesized that longer flat regions of the effective rocker shape would lead to improved standing balance outcomes and reduced walking performance for unilateral transtibial prosthesis users. However, no significant changes were seen in the balance and mobility outcomes of 12 unilateral transtibial prosthesis users when using the three prosthetic foot conditions. Subjects in the study significantly preferred prosthetic feet with relatively low to moderate flat regions over those with long flat regions. All the subjects without loss of light touch or vibratory sensation selected the prosthetic foot with the shortest flat region. More work is needed to investigate the effects of prosthetic foot properties on balance and mobility of prosthesis users.

  9. 21 CFR 870.3945 - Prosthetic heart valve sizer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic heart valve sizer. 870.3945 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3945 Prosthetic heart valve sizer. (a) Identification. A prosthetic heart valve sizer is a device used to measure the size of the...

  10. 42 CFR 414.228 - Prosthetic and orthotic devices.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Prosthetic and orthotic devices. 414.228 Section... Durable Medical Equipment and Prosthetic and Orthotic Devices § 414.228 Prosthetic and orthotic devices. (a) Payment rule. Payment is made on a lump-sum basis for prosthetic and orthotic devices subject to...

  11. 21 CFR 870.3935 - Prosthetic heart valve holder.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic heart valve holder. 870.3935 Section... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3935 Prosthetic heart valve holder. (a) Identification. A prosthetic heart valve holder is a device used to hold a...

  12. 21 CFR 890.3025 - Prosthetic and orthotic accessory.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic and orthotic accessory. 890.3025... (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025 Prosthetic and orthotic accessory. (a) Identification. A prosthetic and orthotic accessory is a device...

  13. Anterior cruciate ligament reconstruction: a look at prosthetics - past, present and possible future

    Science.gov (United States)

    Mascarenhas, Randy; MacDonald, Peter B.

    2008-01-01

    Biological tissue autograft reconstruction using the patellar tendon or quadrupled semitendinosus/gracilis tendons has become the most popular procedure in surgical treatment of a ruptured ACL. This article provides a review of the history of the use of prosthetics with respect to ACL reconstruction grafts including Carbon Fibre, Gore-Tex and Dacron prosthetics as well as the Leeds-Keio Artificial Ligament and the Kennedy Ligament Augmentation Device (LAD). Emphasis is placed on the Ligament Advanced Reinforcement System (LARS) as preliminary investigations of its use have been encouraging. Significant progress has been made recently with respect to the understanding of ACL anatomy, composition, biomechanics, and healing processes, leading to innovative techniques using approaches based in tissue engineering principles and computer – assisted surgery. While research into improved ACL treatment options continues, the synthesis of recent advancements provides a new optimism towards the regeneration of an ACL mirroring its original stability, function, and longevity. PMID:18523530

  14. Hamster (Mesocricetus auratus cheek pouch as an experimental model to investigate human skin and keloid heterologous graft Bolsa jugal no hamster (Mesocricetus auratus como modelo experimental de investigação de enxertos heterólogos de pele humana e quelóide

    Directory of Open Access Journals (Sweden)

    Bernardo Hochman

    2004-12-01

    Full Text Available To describe the integration process of grafts of total human skin and keloid in hamster (Mesocricetus auratus cheek pouch, whose sub-epithelium is naturally an "Immunologically Privileged Site". Fragments of human normal skin and keloid from the breast region of mulatto female patients were transplanted into the cheek pouch subepithelium in situ. Surgical procedure and grafted pouches for microscopic exam at several time points of the transplantation were standardized. The integration of grafted fragments of human skin and keloid was seen in late periods (84 days since the microscopic assessment showed the presence of blood vases within the conjunctive tissue of grafted fragments. It was also possible to see among the grafted fragments the epithelium, the appearing of early cellular infiltrated, epithelial secretion of keratin, the presence of melanocytes, and delayed changes on the aspect of collagen fibers of conjunctive tissue. Pooled results allow to define hamster cheek pouch sub-epithelium as an experimental model to investigating heterologous graft physiology of human total skin and keloid with epithelium.Descrever a integração dos enxertos de pele total humana e quelóide na bolsa jugal do hamster (Mesocricetus auratus, cujo subepitélio é, naturalmente, um "Local de Privilégio Imunológico". Foram transplantados fragmentos, de pele humana normal e de quelóide, obtidos da região mamária de pacientes pardas, no subepitélio da bolsa jugal in situ. O procedimento operatório, e de preparo das bolsas enxertadas para exame microscópico em vários períodos de transplante, foi padronizado. Verificou-se a integração dos fragmentos enxertados de pele humana e de quelóide em períodos tardios (84 dias, uma vez que a avaliação microscópica revelou a presença de vasos sangüíneos no tecido conjuntivo dos fragmentos enxertados. Foi também possível observar, nos fragmentos enxertados, o epitélio, o aparecimento de infiltrado

  15. A novel initiating system for wool grafting

    Directory of Open Access Journals (Sweden)

    Magdy Kandil Zahran

    2016-05-01

    Full Text Available This paper describes a new method for the grafting of methacrylic acid (MAA and other acrylic monomers onto wool fabric in aqueous medium. The novelty principally concerns the chemical approach of the redox grafting reaction that was carried out in the presence of sodium perborate (SPB initiator. Before the grafting reaction was started, the wool fabric was treated first with a freshly prepared ferrous ammonium sulfate (FAS solution. The so-treated fabric formed, with SPB, an efficacious redox system capable of initiating grafting of methacrylic acid (MAA and other acrylic monomers onto the wool fabric. The effect of the polymerization conditions on the polymer criteria, namely, graft yield (%GY, homopolymer (%HP, total conversion (%TC, and grafting efficiency (%GE, was studied. These polymer criteria were found to depend spaciously upon concentrations of the Fe2+ ion (activator, SPB (initiator, and MAA, pH of the polymerization medium, duration and temperature of polymerization. The graft copolymerization reaction has also been carried out in the presence of polymerization activators (e.g. reductant transition metal ions and an inhibitor (e.g. hydroquinone. A suitable mechanism for the grafting processes has been suggested, in accordance with the experimental results.

  16. EEG Mind Controlled Smart Prosthetic Arm – A Comprehensive Study

    Directory of Open Access Journals (Sweden)

    Taha Beyrouthy

    2017-06-01

    Full Text Available Recently, the field of prosthetics has seen many accomplishments especially with the integration of technological advancements. In this paper, different arm types (robotic, surgical, bionic, prosthetic and static are analyzed in terms of resistance, usage, flexibility, cost and potential. Most of these techniques have some problems; they are extremely expensive, hard to install and maintain and may require surgery. Therefore, our work introduces the initial design of an EEG mind controlled smart prosthetic arm. The arm is controlled by the brain commands, obtained from an electroencephalography (EEG headset, and equipped with a network of smart sensors and actuators that give the patient intelligent feedback about the surrounding environment and the object in contact. This network provides the arm with normal hand functionality, smart reflexes and smooth movements. Various types of sensors are used including temperature, pressure, ultrasonic proximity sensors, accelerometers, potentiometers, strain gauges and gyroscopes. The arm is completely 3D printed built from various lightweight and high strength materials that can handle high impacts and fragile elements as well. Our project requires the use of nine servomotors installed at different places in the arm. Therefore, the static and dynamic modes of servomotors are analyzed. The total cost of the project is estimated to be relatively cheap compared to other previously built arms. Many scenarios are analyzed corresponding to the actions that the prosthetic arm can perform, and an algorithm is created to match these scenarios. Experimental results show that the proposed EEG Mind-controlled Arm is a promising alternative for current solutions that require invasive and expensive surgical procedures.

  17. Responsiveness of outcome measures for upper limb prosthetic rehabilitation.

    Science.gov (United States)

    Resnik, Linda; Borgia, Matthew

    2016-02-01

    There is limited research on responsiveness of prosthetic rehabilitation outcome measures. To examine responsiveness of the Box and Block test, Jebsen-Taylor Hand Function tests, Upper Extremity Functional Scale, University of New Brunswick skill and spontaneity tests, Activity Measure for Upper Limb Amputation, and the Patient-Specific Functional Scale. This was a quasi-experimental study with repeated measurements in a convenience sample of upper limb amputees. Measures were collected before, during, and after training with the DEKA Arm. Largest effect sizes were observed for Patient-Specific Functional Scale (effect size: 1.59, confidence interval: 1.00, 2.14), Activity Measure for Upper Limb Amputation (effect size: 1.33, confidence interval: 0.73, 1.90), and University of New Brunswick skill test (effect size: 1.18, confidence interval: 0.61, 1.73). Other measures that were responsive to change were Box and Block test, Jebsen-Taylor Hand Function light and heavy can tests, and University of New Brunswick spontaneity test. Responsiveness and pattern of responsiveness varied by prosthetic level. The Box and Block test, Jebsen-Taylor Hand Function light and heavy can tests, University of New Brunswick skill and spontaneity tests, Activities Measure for Upper Limb Amputation, and the Patient-Specific Functional Scale were responsive to change during prosthetic training. These findings have implications for choice of measures for research and practice and inform clinicians about the amount of training necessary to maximize outcomes with the DEKA Arm. Findings on responsiveness of outcome measures have implications for the choice of measures for clinical trials and practice. Findings regarding the responsiveness to change over the course of training can inform clinicians about the amount of training that may be necessary to maximize specific outcomes with the DEKA Arm. © The International Society for Prosthetics and Orthotics 2014.

  18. Grafting and curing

    International Nuclear Information System (INIS)

    Garnett, J.L.; Loo-Teck Ng; Visay Viengkhou

    1998-01-01

    Progress in radiation grafting and curing is briefly reviewed. The two processes are shown to be mechanistically related. The parameters influencing yields are examined particularly for grafting. For ionising radiation grafting systems (EB and gamma ray) these include solvents, substrate and monomer structure, dose and dose-rate, temperature and more recently role of additives. In addition, for UV grafting, the significance of photoinitiators is discussed. Current applications of radiation grafting and curing are outlined. The recent development of photoinitiator free grafting and curing is examined as well as the potential for the new excimer laser sources. The future application of both grafting and curing is considered, especially the significance of the occurrence of concurrent grafting during cure and its relevance in environmental considerations

  19. The comparison of acellular dermal matric (Alloderm), Dacron, Gore-Tex, and autologous cartilage graft materials in an experimental animal model for nasal septal repair surgery.

    Science.gov (United States)

    Mola, Ferhat; Keskin, Gurkan; Ozturk, Murat; Muezzinoglu, Bahar

    2007-01-01

    The aim of this study was to compare the compatibility of Alloderm, Dacron, Gore-Tex, and autologous cartilage graft materials with host tissues in nasal septal perforation repair surgery. The materials were placed into the nasal septum of 16 New Zealand rabbits. At the end of the 3rd month, septums of the rabbits were removed totally and reactions, such as inflammation;foreign body giant cell; or fibrosis that developed in the surrounding tissue against the implant material were evaluated. Acute inflammation reactions occurred mostly with Gore-Tex. There were no differences between groups according to chronic inflammation. When the number of reactions and tissue compatibility were taken into consideration, cartilage performed the best followed by Alloderm. There were more reactions with Dacron, but it still showed compatibility. Cartilage was found to be the best material followed by Alloderm and Dacron, but Gore-Tex was found unsuitable.

  20. Peri-prosthetic fracture vibration testing

    Energy Technology Data Exchange (ETDEWEB)

    Cruce, Jesse R [Los Alamos National Laboratory; Erwin, Jenny R [Los Alamos National Laboratory; Remick, Kevin R [Los Alamos National Laboratory; Cornwell, Phillip J [Los Alamos National Laboratory; Menegini, R. Michael [INDIANA UNIV.; Racanelli, Joe [STRYKER ORTHOPARDICS

    2010-11-08

    The purpose of this study was to establish a test setup and vibration analysis method to predict femoral stem seating and prevent bone fracture using accelerometer and force response data from an instrumented stem and impactor. This study builds upon earlier studies to identify a means to supplement a surgeon's tactile and auditory senses by using damage identification techniques normally used for civil and mechanical structures. Testing was conducted using foam cortical shell sawbones prepared for stems of different geometries. Each stem was instrumented with an accelerometer. Two impactor designs were compared: a monolithic impactor and a two-piece impactor, each with an integrated load cell and accelerometer. Acceleration and force measurements were taken in the direction of impaction. Comparisons between different methods of applying an impacting force were made, including a drop tower and a surgical hammer. The effect of varying compliance on the data was also investigated. The ultimate goal of this study was to assist in the design of an integrated portable data acquisition system capable of being used in future cadaveric testing. This paper will discuss the experimental setup and the subsequent results of the comparisons made between impactors, prosthetic geometries, compliances, and impact methods. The results of this study can be used for both future replicate testing as well as in a cadaveric environment.

  1. The mechanism of mediated oxidation of carboxylates with ferrocene as redox catalyst in absence of grafting effects. An experimental and theoretical approach

    International Nuclear Information System (INIS)

    Hernández-Muñoz, Lindsay S.; Galano, Annia; Astudillo-Sánchez, Pablo D.; Abu-Omar, Mahdi M.; González, Felipe J.

    2014-01-01

    Graphical abstract: - Highlights: • The mechanism of mediated oxidation of carboxylates. • Thermodynamics of the mediated Kolbe and Non-Kolbe mechanisms. • The oxidation of acetate and diphenylacetate ions by using ferrocene as redox catalyst. • Simulation and DFT calculations of the mediated oxidation of carboxylates. • Radical and carbocationic pathways in the carboxylate oxidation in acetonitrile. - Abstract: The oxidation of tetrabutylammonium carboxylates by using ferrocene derivatives as redox mediators has been recently used to perform the covalent grafting of carbon surfaces with organic and organometallic groups. Due to the intervention of this surface process, a partial description of the reaction mechanism has only been stated. Therefore, this article concerns about two features of the oxidation of carboxylates mediated by ferrocene. In the first part, it is discussed that in the oxidation of acetate ions by using ferrocene as redox catalyst, the gap between both oxidation potentials is very high, which means that the homogeneous electron transfer between the acetate ion and the electrochemically generated ferrocenium ion is energetically unfavorable. However, by using density functional theory calculations, it has been shown that the whole set of coupled chemical reactions involved either in a Kolbe or Non-Kolbe pathway drive the overall mechanisms towards a thermodynamically favorable situation. In order to avoid the strong covalent grafting process that occurs during the mediated oxidation of acetate ions, the second part of this work deals with the oxidation of tetrabutylammonium diphenylacetate by using ferrocene as a redox mediator in acetonitrile on glassy carbon electrodes. With this carboxylate, no electrode inhibition process occurs and, therefore cyclic voltammetry simulation was done to propose the electrochemical and chemical steps that are present when a carboxylate oxidation is performed in the presence of ferrocene derivatives

  2. Advanced upper limb prosthetic devices: implications for upper limb prosthetic rehabilitation.

    Science.gov (United States)

    Resnik, Linda; Meucci, Marissa R; Lieberman-Klinger, Shana; Fantini, Christopher; Kelty, Debra L; Disla, Roxanne; Sasson, Nicole

    2012-04-01

    The number of catastrophic injuries caused by improvised explosive devices in the Afghanistan and Iraq Wars has increased public, legislative, and research attention to upper limb amputation. The Department of Veterans Affairs (VA) has partnered with the Defense Advanced Research Projects Agency and DEKA Integrated Solutions to optimize the function of an advanced prosthetic arm system that will enable greater independence and function. In this special communication, we examine current practices in prosthetic rehabilitation including trends in adoption and use of prosthetic devices, financial considerations, and the role of rehabilitation team members in light of our experiences with a prototype advanced upper limb prosthesis during a VA study to optimize the device. We discuss key challenges in the adoption of advanced prosthetic technology and make recommendations for service provision and use of advanced upper limb prosthetics. Rates of prosthetic rejection are high among upper limb amputees. However, these rates may be reduced with sufficient training by a highly specialized, multidisciplinary team of clinicians, and a focus on patient education and empowerment throughout the rehabilitation process. There are significant challenges emerging that are unique to implementing the use of advanced upper limb prosthetic technology, and a lack of evidence to establish clinical guidelines regarding prosthetic prescription and treatment. Finally, we make recommendations for future research to aid in the identification of best practices and development of policy decisions regarding insurance coverage of prosthetic rehabilitation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  3. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

    Full Text Available Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation.

  4. Estudo experimental da influência da altura do enxerto ósseo intersomático na estabilidade da fixação monossegmentar anterior da coluna cervical Experimental study of the impact of intersomatic bone graft height on the stability of anterior monosegmental fixation of the cervical spine

    Directory of Open Access Journals (Sweden)

    Jorge Alfredo Léo

    2008-06-01

    Full Text Available OBJETIVO: Estudar experimentalmente a influência da altura do enxerto ósseo intersomático da coluna cervical na estabilidade mecânica da fixação cervical anterior. MÉTODOS: Foram realizados ensaios mecânicos utilizando a coluna cervical de suínos (C3-C4. Foram formados três grupos experimentais compostos por 20 segmentos da coluna cervical (C3-C4, de acordo com o grau de instabilidade produzido e a fixação do segmento vertebral. Grupo I: retirada do disco intervertebral e colocação de enxerto intersomático. Grupo II: retirada do disco intervertebral, colocação de enxerto intersomático e fixação anterior com placa. Grupo III: retirada do disco intervertebral, secção dos ligamentos posteriores e cápsulas articulares bilateralmente, colocação do enxerto intersomático e fixação anterior com placa. Cada grupo experimental foi dividido em dois subgrupos, de acordo com a altura do enxerto ósseo utilizado (3,0mm ou 6,0mm. Os segmentos vertebrais foram submetidos a ensaios mecânicos de flexão, flexão lateral e torção em máquina universal de ensaio. Os parâmetros analisados foram força máxima (N e o momento (Nm para produzir uma deflexão preestabelecida. RESULTADOS: Não foi observada em todos os grupos experimentais diferença estatística dos valores da força máxima (N e do momento (Nm, entre as diferentes alturas (3,0mm e 6,0mm do enxerto ósseo intersomático. Conclusões: A estabilidade mecânica imediata da artrodese cervical monossegmentar anterior não sofreu influência da altura do enxerto ósseo intersomático nos ensaios de flexão, flexão lateral e torção.OBJECTIVE: To perform an experimental study of the impact of intersomatic bone graft height of the cervical spine on the mechanical stability of anterior cervical fixation. METHODS: Mechanical assays were performed using swine cervical spine (C3-C4. Three experimental groups were formed with 20 cervical spine segments (C3-C4 according to the degree

  5. DME Prosthetics Orthotics, and Supplies Fee Schedule

    Data.gov (United States)

    U.S. Department of Health & Human Services — Durable Medical Equipment, Prosthetics-Orthotics, and Supplies Fee Schedule. The list contains the fee schedule amounts, floors, and ceilings for all procedure codes...

  6. Successful Thrombolysis of Aortic Prosthetic Valve Thrombosis ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    threatening. Standard surgical treatment using cardiopulmonary bypass carries high maternal and fetal complications. Here we report a case of an antenatal female in first trimester with aortic prosthetic valve thrombosis (PVT), who was successfully ...

  7. Computed Tomography of Prosthetic Heart Valves

    NARCIS (Netherlands)

    Habets, J.

    2012-01-01

    Prosthetic heart valve (PHV) dysfunction is an infrequent but potentially life-threatening disease with a heterogeneous clinical presentation. Patients with PHV dysfunction clinically can present with symptoms of congestive heart failure (dyspnea, fatigue, edema), fever, angina pectoris, dizziness

  8. Stump ulcers and continued prosthetic limb use.

    Science.gov (United States)

    Salawu, A; Middleton, C; Gilbertson, A; Kodavali, K; Neumann, V

    2006-12-01

    Stump ulcers are common problems in amputees. Temporary discontinuation of prosthetic limb use is frequently employed to facilitate healing. Inevitably, this limits activity and may, for instance, prevent an amputee from going to work. A survey of clinical practice was carried out based on the premise that controlled continued prosthetic limb use in patients with stump ulcers will not adversely affect the ulcer nor prevent healing. The survey would also form a basis for developing future guidelines in the management of stump ulcers. All consecutive patients attending the Chapel Allerton Hospital prosthetic clinic between January 2003 and May 2004 with stump ulcers were recruited into the study. Primary outcome measures were changes in the surface area of the ulcers and in clinical photographs taken on 2 occasions 6 weeks apart. Some 102 patients with a mean age 60 years (range 18 - 88 years) were recruited. Eight patients who were established prosthetic limb users did not complete the study and were excluded from the analysis. Of the patients 52 were newly referred patients with delayed surgical wound healing while 42 were established prosthetic limb users for at least 1 year. Continued prosthetic limb was associated with a significant reduction in ulcer size (p prosthetic limb wearing despite the presence of stump ulceration. This observational study found that, despite prosthetic use, 60 (64%) cases healed completely within the six-week study period and 23 (25%) ulcers reduced in size. The ulcers were unchanged in 2% of the cases. Deterioration was observed in nine (9%) cases. This survey suggests that the current practice of allowing patients to use their prostheses is safe. A clinical trial is now needed to establish whether this practice alters healing rate or has any other disadvantages for new or established amputees.

  9. Surgical and Prosthetic Rehabilitation of Combination Syndrome

    Directory of Open Access Journals (Sweden)

    Paolo Carlino

    2014-01-01

    Full Text Available The aim of this report is to analyze the clinical symptoms, ethologic factors, and prosthetic rehabilitation in a case of Combination Syndrome (CS. The treatment of CS can be conventional or surgical, with or without the bone reconstruction of maxilla. The correct prosthetic treatment helps this kind of patients to restore the physiologic occlusion plane to allow a correct masticatory and aesthetic function. Management of this kind of patients can be a challenge for a dental practitioner.

  10. Exploring virtual reality and prosthetic training.

    OpenAIRE

    Phelan, Ivan; Arden, Madelynne; Garcia, Carol; Roast, Chris

    2015-01-01

    Working together with health care professionals and a world\\ud leading bionic prosthetic maker we created a prototype that aims to decrease the time it takes for a transradial amputee to train how to use a Myoelectric prosthetic arm. Our research indicates that the Oculus Rift, Microsoft’s Kinect and the Thalmic Labs Myo gesture control armband will allow us to create a unique, cost effective training tool that could be beneficial to amputee patients.

  11. DNA nanosensor surface grafting and salt dependence

    Science.gov (United States)

    Carvalho, B. G.; Fagundes, J.; Martin, A. A.; Raniero, L.; Favero, P. P.

    2013-02-01

    In this paper we investigated the Paracoccidoides brasiliensis fungus nanosensor by simulations of simple strand DNA grafting on gold nanoparticle. In order to improve the knowledge of nanoparticle environment, the addiction of salt solution was studied at the models proposed by us. Nanoparticle and DNA are represented by economic models validated by us in this paper. In addition, the DNA grafting and salt influences are evaluated by adsorption and bond energies calculations. This theoretical evaluation gives support to experimental diagnostics techniques of diseases.

  12. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    International Nuclear Information System (INIS)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae

    1995-01-01

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy

  13. Implications of smart materials in advanced prosthetics

    Science.gov (United States)

    Lenoe, Edward M.; Radicic, William N.; Knapp, Michael S.

    1994-05-01

    This research reviews common implant materials and suggests smart materials that may be used as substitutes. Current prosthetic technology, including artificial limbs, joints, and soft and hard tissue, falls short in comprehensive characterization of the chemo-mechanics and materials relationships of the natural tissues and their prosthetic materials counterparts. Many of these unknown chemo-mechanical properties in natural tissue systems maintain cooperative function that allows for optimum efficiency in performance and healing. Traditional prosthetic devices have not taken into account the naturally occurring electro-chemo-mechanical stress- strain relationships that normally exist in a tissue system. Direct mechanical deformation of tissue and cell membrane as a possible use of smart materials may lead to improved prosthetic devices once the mechanosensory systems in living tissues are identified and understood. Smart materials may aid in avoiding interfacial atrophy which is a common cause of prosthetic failure. Finally, we note that advanced composite materials have not received sufficient attention, they should be more widely used in prosthetics. Their structural efficiency allows design and construction of truly efficient bionic devices.

  14. Kinked Graft and Anastomotic Stenosis-Induced Hemolytic Anemia Requiring Reoperation.

    Science.gov (United States)

    Kitahara, Hiroto; Yoshitake, Akihiro; Hachiya, Takashi; Okamoto, Kazuma; Kawaguchi, Shinji; Shimizu, Hideyuki

    2016-01-01

    We report a case of hemolytic anemia caused initially by narrowing of a proximal anastomotic site and subsequently by a kinked prosthetic graft after total aortic arch replacement. A 55-year-old man was diagnosed with acute type A aortic dissection by computed tomography (CT). After total aortic arch replacement, hemolytic anemia and renal dysfunction developed. CT detected narrowing of proximal anastomotic site of the graft. Removing the graft and ascending aortic replacement resolved the signs of hemolytic anemia. However, 50 days after the surgery, severe hemolytic anemia developed again. CT revealed a sharply kinked graft. Total arch replacement was again performed to resect the kinked graft. He was discharged on the 24th postoperative day without hemodialysis. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Cetacean Swimming with Prosthetic Limbs

    Science.gov (United States)

    Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Fish, Frank

    2016-11-01

    During entanglement in fishing gear, dolphins can suffer abrasions and amputations of flukes and fins. As a result, if the dolphin survives the ordeal, swimming performance is altered. Current rehabilitation technques is the use of prosthesis to regain swimming ability. In this work, analyses are focused on two dolphins with locomotive impairment; Winter (currently living in Clearwater Marine Aquarium in Florida) and Fuji (lived in Okinawa Churaumi Aquarium in Japan). Fuji lost about 75% of its fluke surface to necrosis (death of cells) and Winter lost its tail due to amputation. Both dolphins are aided by prosthetic tails that mimic the shape of a real dolphin tail. Using 3D surface reconstruction techniques and a high fidelity Computational Fluid Dynamics (CFD) flow solver, we were able to elucidate the kinematics and hydrodynamics and fluke deformation of these swimmers to clarify the effectiveness of prostheses in helping the dolphins regain their swimming ability. Associated with the performance, we identified distinct features in the wake structures that can explain this gap in the performance compared to a healthy dolphin. This work was supported by ONR MURI Grant Number N00014-14-1-0533.

  16. The response of the anophthalmic socket to prosthetic eye wear.

    Science.gov (United States)

    Pine, Keith Raymond; Sloan, Brian; Stewart, Joanna; Jacobs, Robert John

    2013-07-01

    The aim of this study was to investigate the inflammatory response of the anophthalmic socket to prosthetic eye wear. One hundred and two prosthetic eye wearers were recruited for this observational study. Photographic grading scales were used to measure the severity of conjunctival inflammation and the extent and intensity of stained deposits on the prosthetic eyes. Tear volume was measured with the phenol red thread test. For mucoid discharge, visual analogue scales were used to assess frequency of occurrence, colour, volume and viscosity. For the prostheses, assessments were made of weight, shape, wearing time and frequency of cleaning. Anophthalmic sockets had more severe conjunctival inflammation than their companion eyes (p = 0.0001). The difference in inflammation between the companion eye and the anophthalmic socket was associated with discharge volume (p = 0.01) and discharge viscosity (p = 0.007) with greater difference in inflammation being associated with higher levels of discharge volume and viscosity. A greater difference in inflammation was also associated with less surface deposition (p = 0.009). No evidence of associations was found between difference in conjunctival inflammation and the other variables. Recently developed grading scales for measuring inflammation in anophthalmic sockets and deposits on prosthetic eyes were used for the first time in this study. It is recommended that in clinical practice, inflammation grades for both socket and companion eye conjunctivae be compared, when determining if prosthesis-induced inflammation is present. The finding that more discharge was associated with more conjunctival inflammation is logical but the finding that less inflammation was associated with more deposits is counter-intuitive to those familiar with the contact lens literature. The apparently benign nature of at least some deposits on the prostheses raises questions about the maintenance of prosthetic eyes. We conclude that the simple presence

  17. The effects of prosthetic ankle stiffness on ankle and knee kinematics, prosthetic limb loading, and net metabolic cost of trans-tibial amputee gait.

    Science.gov (United States)

    Major, Matthew J; Twiste, Martin; Kenney, Laurence P J; Howard, David

    2014-01-01

    Previous studies of commercially-available trans-tibial prosthetic components have been unable to provide clear insight into the relationships between prosthetic mechanical properties and user performance (i.e., gait quality and energy expenditure), the understanding of which is key to improving prosthesis design and prescription. Many of these studies have been limited by not characterising the mechanical properties of the tested prostheses and/or only considered level walking at self-selected speeds. The aim of this study was to conduct a systematic investigation of the effects of ankle rotational stiffness on trans-tibial amputee gait during various walking conditions reflective of those encountered during daily ambulation. Ankle and knee kinematics, prosthetic limb normal ground reaction forces, and net metabolic cost were measured in five traumatic unilateral trans-tibial amputees during treadmill walking on the level, a 5% incline and a 5% decline whilst using an experimental articulated prosthetic foot with four different rotational stiffness setups and without changes in alignment between conditions. Overall, lower dorsiflexion stiffness resulted in greater prosthetic side dorsiflexion motion and sound side knee flexion, reduced normal ground reaction force during the loading phase of prosthetic stance and reduced net metabolic cost. Few differences were observed with changes in plantarflexion stiffness, most likely due to the foot achieving early foot flat. Low dorsiflexion stiffness generally improved gait performance seemingly due to easier tibial progression during stance. However, observed differences were small, suggesting that a wider range of walking and stiffness conditions would be useful to fully explore these effects in future studies. © 2013.

  18. Experimental studies on glycerol preserved vascular allografts

    NARCIS (Netherlands)

    Fahner, P.J.

    2014-01-01

    Autologous vein is the conduit of choice in patients with critical peripheral arterial disease who need a vascular reconstruction. However, autologous vein could be of inferior quality or used in prior surgery. Vascular allograft transplantation is an attractive alternative to prosthetic grafts in

  19. Percutaneous management of prosthetic valve thrombosis.

    Science.gov (United States)

    Hariram, Vuppaladadhiam

    2014-01-01

    Thrombosis of a prosthetic valve is a serious complication in patients with prosthetic heart valves. Thrombolysis is the initial choice of treatment. Patients who do not respond to thrombolysis are subjected to surgery which carries a high risk. We report a case series of 5 patients with prosthetic mitral valve thrombosis who did not respond to thrombolysis and were subjected to percutaneous manipulation of the prosthetic valves successfully and improved. Five patients who were diagnosed to have prosthetic mitral valve thrombosis and failed to respond to a minimum of 36 h of thrombolysis (persistent symptoms with increased gradients, abnormal findings on fluoroscopy),were subjected to percutaneous treatment after receiving proper consent. None of them had a visible thrombus on transthoracic echocardiogram. All patients underwent transseptal puncture following which a 6F JR4 guiding catheter was passed into the left atrium. The valve leaflets were repeatedly hit gently under fluoroscopic guidance till they regained their normal mobility. Mean age was 38.8 years. Average peak and mean gradients prior to the procedure were 38 and 25 and after the procedure were 12 and 6 mm of Hg respectively. All patients had successful recovery of valve motion on fluoroscopy with normalization of gradients and complete resolution of symptoms. None of the patients had any focal neurological deficits, embolic manifestations or bleeding complications. Percutaneous manipulation of prosthetic valves in selected patients with prosthetic valve thrombosis who do not respond to thrombolytic therapy is feasible and can be used as an alternative to surgery. Copyright © 2014 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  20. The effect of carbon dioxide therapy on composite graft survival

    OpenAIRE

    Durães, Eliana Ferreira Ribeiro; Durães, Leonardo de Castro; Carneiro, Fabiana Pirani; Lino Júnior, Ruy de Souza; Sousa, João Batista de

    2013-01-01

    PURPOSE: To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. METHODS: An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, h...

  1. [Ocular prosthetics. Fitting, daily use and complications].

    Science.gov (United States)

    Koch, K R; Trester, W; Müller-Uri, N; Trester, M; Cursiefen, C; Heindl, L M

    2016-02-01

    Ocular prosthetics make a decisive contribution to the functional, esthetic and psychosomatic rehabilitation of patients after ocular extirpation. This article provides an overview of the fitting, daily care and complications of ocular prosthetics. The study comprised a PubMed literature review and own clinical results. Ocular prosthetics made from cryolite glass or perspex can be manufactured and fitted 5-8 weeks after removal of the eye. During this period a conformer is placed within the conjunctival sac in order to prevent scar formation and shrinking of the socket. Artificial eyes can be worn continuously, only interrupted by a short but regular cleaning procedure. Artificial tears and lid hygiene improve the comfort of wearing. Glass prostheses have to be renewed every 1-2 years, while perspex prostheses need to be polished once a year. Complications, such as giant papillary conjunctivitis or blepharoconjunctivitis sicca are facilitated by poor fit, increased age and inappropriate care of the prosthetic device. In the case of socket shrinkage or anophthalmic socket syndrome, surgical interventions are needed to re-enable the use of an artificial eye. Adequate fitting, daily care of ocular prosthetics and therapeutic management of associated complications are mandatory for a durable functional, esthetic and psychosomatic rehabilitation after ocular extirpation.

  2. Effect of a selective thromboxane synthase inhibitor on arterial graft patency and platelet deposition in dogs

    International Nuclear Information System (INIS)

    McDaniel, M.D.; Huntsman, W.T.; Miett, T.O.; Cronenwett, J.L.

    1987-01-01

    This study examined the effect of selective thromboxane synthase inhibition and nonselective cyclooxygenase inhibition on vascular graft patency and indium 111-labeled platelet deposition in 35 mongrel dogs undergoing carotid artery replacement with 4 mm X 4 cm polytetrafluoroethylene (PTFE) (one side) and Dacron (opposite side) end-to-end grafts. Aspirin-dipyridamole therapy improved one-week graft patency, from 46% in untreated dogs to 93% in treated dogs. Thromboxane synthase inhibition (U-63557A) improved graft patency in these dogs to 81%. Both drug treatments reduced platelet deposition on Dacron and PTFE grafts by 48% to 68% compared with control dogs. Dacron grafts accumulated significantly more platelets than PTFE grafts but had comparable patency rates. Low-dose aspirin therapy had no significant effect on either graft patency or platelet deposition. All treatment groups showed a 60% to 76% reduction in serum thromboxane B2, but only thromboxane synthase inhibitor treatment increased plasma 6-keto-prostaglandin F1 alpha by 100%. Selective thromboxane synthase inhibition improved small-caliber prosthetic graft patency to the same extent as did conventional cyclooxygenase inhibition in this preliminary study

  3. [New technologies in the prosthetic management after amputations].

    Science.gov (United States)

    Schäfer, M; Gawron, O

    2015-06-01

    In Germany around 70,000 amputations are carried out on extremities each year. Modern prosthetic functional components have become more and more sophisticated and must be understood and applied by their users to be of beneficial use in everyday life. The prosthetic socket is the most important component of modern extremity prosthetics. Which demands have to be met by a modern prosthetic socket so that innovative function-improving components in prosthetics can be successfully applied? Complex prosthetic technologies are rarely compatible with a lower overall weight of the prosthesis. The increase in functionality also produces differentiated force effects on the human body. Modern socket technologies, therefore, have to compensate for the increased strain and counteract the increasing dynamics between the stump and the prosthesis. This can be achieved through the application of adhesive socket materials and through new adhesive mechanisms. Form variants can also improve the connection between stump and prosthetic socket. The improvements in prosthetic socket technology presented here have a lasting positive effect on the daily routine of many amputees. Not only do they improve the control and application of modern prosthetic components, but also clearly enhance the wearing comfort. The prosthetic socket is crucial for the success of exoskeletal prosthetic management. The better we succeed in making the human body and the prosthetic socket an entity, the more usefully and comfortably innovative prosthetic methods can be applied.

  4. Engineered vascularized bone grafts

    OpenAIRE

    Tsigkou, Olga; Pomerantseva, Irina; Spencer, Joel A.; Redondo, Patricia A.; Hart, Alison R.; O’Doherty, Elisabeth; Lin, Yunfeng; Friedrich, Claudia C.; Daheron, Laurence; Lin, Charles P.; Sundback, Cathryn A.; Vacanti, Joseph P.; Neville, Craig

    2010-01-01

    Clinical protocols utilize bone marrow to seed synthetic and decellularized allogeneic bone grafts for enhancement of scaffold remodeling and fusion. Marrow-derived cytokines induce host neovascularization at the graft surface, but hypoxic conditions cause cell death at the core. Addition of cellular components that generate an extensive primitive plexus-like vascular network that would perfuse the entire scaffold upon anastomosis could potentially yield significantly higher-quality grafts. W...

  5. Emprego de enxerto biológico na reconstrução de ferida experimental no esôfago cervical de ovinos Use of biological graft in the reconstruction of experimental wound of the cervical esophagus in sheep

    Directory of Open Access Journals (Sweden)

    D.R. Stainki

    2001-08-01

    Full Text Available Dezoito ovelhas foram divididas em dois grupos (I e II de nove animais, e cada grupo dividido em dois subgrupos (Ia, Ib e IIa, IIb conforme o tempo de avaliação, de 45 dias para os subgrupos a e de 60 dias para os subgrupos b. Todos os animais tiveram um segmento esofágico retangular de 2,5×1,5cm removido. Os animais do grupo I receberam enxerto de aorta canina, enquanto os do grupo II receberam enxerto de fáscia lata canina. Todos os enxertos foram previamente conservados entre 30 e 90 dias em glicerina 98%. A integração dos enxertos foi avaliada por meio de exame clínico (inspeção da ferida cirúrgica, comportamento quanto ao apetite e sede, capacidade de deglutição e regurgitação, hemograma completo, esofagograma contrastado e análises macroscópica e histopatológica. Concluiu-se que os tecidos enxertados foram suficientes para suportar a pressão da passagem do alimento e para a vedação esofágica, oferecendo condições para a regeneração epitelial.Eighteen sheep were equally divided into two groups (I and II and into four subgroups (Ia, Ib, IIa, IIb according to two distinct periods of time previously set for postoperative observation. Subgroups a and b were maintained under observation for 45 and 60 days, respectively. All animals had undergone an esophageal segment excisions of 1.5×2.5cm which were corrected with a biological graft conserved by a period between 30 and 90 days in glycerin 98%. A thoracic aortic graft was used in group I and canine fascia lata graft in group II. Postoperative evaluation consisted of clinical observation as well as laboratorial and radiographic exams. At the end of each period, the animals from corresponding groups were euthanized and the esophageal segments were evaluated macro and microscopically. It was observed that these heterografts were resistant to the passage of food and efficient in the closure of esophageal wounds, offering adequate surface for epithelial regeneration.

  6. Prosthetic status and prosthetic needs amongst geriatric fishermen population of Kutch coast, Gujarat, India.

    Science.gov (United States)

    Kumar, Dola Rama Venkata; Raju, Datla Srinivasa; Naidu, Lakshmu; Deshpande, Sumit; Chadha, Manish; Agarwal, Abhinav

    2015-01-01

    Literature among fishermen of India is scanty. The external factors like diet, quality of dental hygiene and environmental factors have an effect on oral health. Moreover elderly age group offer very little importance towards their oral health. To assess the prosthetic status and prosthetic treatment needs among the geriatric fishermen population of Kutch coast, Gujarat, India. A cross sectional descriptive study was conducted among 1200 elderly people (above 60 years) of Kutch coast, Gujarat, India. They were interviewed and examined using a proforma designed with the help of WHO Oral Health Survey 1997. Chi square test was used for comparisons. Confidence level and p-value were set at 95% and 5% respectively. Out of 1200 elderly people, 836 were males and 364 were females. Considering the prosthetic status, majority (76.7%) had no prosthesis followed by full removable dentures (12.3%). An insight into the prosthetic needs showed that majority (27.3%) had a need for multiunit prosthesis. In this study, it was seen that overall prosthetic status was low and prosthetic need was high. Therefore new avenues have to be discovered to make the prosthetic treatment readily available to the elderly.

  7. Concepção de bancada e montagem de experimento para a análise in vitro de próteses cardíacas mitrais Design conception and experimental setup for in vitro evaluation of mitral prosthetic valves

    Directory of Open Access Journals (Sweden)

    Ovandir Bazan

    2011-06-01

    prosthetic heart valves is due to disturbances of flow, its hydrodynamic characterization is a useful aid in the design of new prostheses. Simulations of pulsatile flow in cardiac prostheses began nearly 40 years ago, through the development of different mock human circulatory systems, improving the clinical results interpretation. A new design of a pulse duplicator system was developed at Polytechnic School of USP to study prosthetic heart valves. OBJECTIVE: To present the conception of a new mock circulatory system for hydrodynamic simulations of cardiac prosthetic valves and the assembly plan of an experiment whose focus is the test of mitral prosthesis. METHODS: Its conception is based on the state-of-art's review of these studies and the experience got with the previous mock circulatory systems, particularly the one used in the Instituto Dante Pazzanese de Cardiologia, São Paulo, SP, Brazil. RESULTS: In this design, an electric servomotor controlled by computer emits, through a hydraulic piston, a pulse to the left ventricular chamber model, where the heart valves are accomodated. To characterize, in the future, the dynamic operation of mitral prosthetic valves, an experimental setup was mounted to provide measurements of volumetric flow, instantaneous pressure and velocity fields on these valves. Optical access is conveniently provided on the design, making possible the use, in the future, of a LDA system. CONCLUSIONS: In order to improve the analysis of hydrodynamic shear stress and prediction of haemolysis, the experimental results may be used to regulate a numerical model using 'Computational Fluid Dynamics' (CFD.

  8. Ceratoplastia lamelar em cães utilizando membrana fetal eqüina como enxerto: estudo experimental Lamelar keratoplasty in dogs using equine fetal membrane as graft: experimental study

    Directory of Open Access Journals (Sweden)

    Cintia Aparecida Lopes Godoy

    2002-09-01

    Full Text Available Objetivo: Avaliar o emprego da membrana fetal (membrana amniótica, córion e alantóide eqüina como enxerto em ceratoplastia lamelar em cães. Métodos: Foram utilizados 9 animais SRD, respeitando as normas para experimentos em animais da ARVO - Association for Research in Vision and Ophthalmology. Ceratectomia semipenetrante foi realizada com o auxílio de trépano de 5 mm de diâmetro em região temporal superior, com subseqüente fixação de fragmento de membrana fetal eqüina de 6 mm de diâmetro com fio mononylon 8-0. Realizou-se avaliação clínica durante 2, 7, 15 e 60 dias. Os animais foram sacrificados e os olhos enucleados submetidos a estudo histológico. Resultados: Observou-se clinicamente edema moderado nas áreas circunjacentes ao implante desde o início até a fase intermediária do experimento. A neovascularização apareceu de maneira progressiva, com maior intensidade no período intermediário, regredindo paulatinamente. Aos 60 dias, notava-se uma mácula no local da cirurgia. Os achados histológicos demonstraram epitelização e perfeita integração do enxerto ao tecido autóctone logo aos 7 dias de evolução, quando também evidenciou respostas celular e vascular mais intensas. Aos 15 dias, verificou-se diminuição dos elementos vasculares em relação à quantidade de matriz e elementos celulares proliferados. Constatou-se ausência quase total de infiltrado inflamatório no enxerto e nos pontos de sutura. Conclusão: O emprego da membrana fetal (membrana amniótica, córion e alantóide eqüina como enxerto em ceratoplastia lamelar em cães é factível e produz bons resultados.Purpose: To evaluate the applicability of the equine fetal membrane (amniotic membrane, chorion and alantoid as graft in lamelar keratoplasty in dogs. Methods: 9 mixed breed dogs were used, according to the ARVO statement for use of animals in ophthalmic and vision research. Superficial keratectomy was performed with a 5 mm trephine and a

  9. Bruxism and prosthetic treatment: a critical review.

    Science.gov (United States)

    Johansson, Anders; Omar, Ridwaan; Carlsson, Gunnar E

    2011-07-01

    Based on the findings from available research on bruxism and prosthetic treatment published in the dental literature, an attempt was made to draw conclusions about the existence of a possible relationship between the two, and its clinical relevance. MEDLINE/PubMed searches were conducted using the terms 'bruxism' and 'prosthetic treatment', as well as combinations of these and related terms. The few studies judged to be relevant were critically reviewed, in addition to papers found during an additional manual search of reference lists within selected articles. Bruxism is a common parafunctional habit, occurring both during sleep and wakefulness. Usually it causes few serious effects, but can do so in some patients. The etiology is multifactorial. There is no known treatment to stop bruxism, including prosthetic treatment. The role of bruxism in the process of tooth wear is unclear, but it is not considered a major cause. As informed by the present critical review, the relationship between bruxism and prosthetic treatment is one that relates mainly to the effect of the former on the latter. Bruxism may be included among the risk factors, and is associated with increased mechanical and/or technical complications in prosthodontic rehabilitation, although it seems not to affect implant survival. When prosthetic intervention is indicated in a patient with bruxism, efforts should be made to reduce the effects of likely heavy occlusal loading on all the components that contribute to prosthetic structural integrity. Failure to do so may indicate earlier failure than is the norm. Copyright © 2011 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  10. [Multiple agenesis and prosthetic restoration].

    Science.gov (United States)

    Renault, P

    1990-03-01

    Cases of multiple agenesia present some difficulties in the treatment planing. Three situations may be encountered: limited agenesia, restored by a fixed, bonded or cemented prosthesis, multiple uni- or bimaxillary agenesia without remaining of deciduous teeth, restored by a fixed, bonded or cemented prosthesis or the partial adjacent prosthesis, multiple uni- or bimaxillary agenesia with remaining of deciduous teeth, restored by means of a supra-dental prosthesis. The first two situations have been described in dental literature and are relatively easy to treat. The same is not true for the third situation, where the decision to keep the temporary teeth considerably increases the difficulty of prosthetic restoration. This subject will be illustrated by the presentation of a clinical case of multiple bi-maxillary agenesia. The patient has: on the maxilla: an absence of 9 permanent teeth (18, 15, 14, 12, 22, 23, 24, 25, 28) and the presence of 4 deciduous teeth (62, 63, 64, 65), on the mandible: an absence of all permanent teeth, with the exception of 36 and 46, and the remaining of 4 deciduous teeth (75, 73, 83, 84). The remaining of deciduous teeth and the presence of a very high inter-arch space led to opting for dental coverage so as to keep the deciduous teeth and a proper vertical dimension. The patient wished to solve his "problem" in the maxilla first, and is not wanting to undergo the extraction of his deciduous teeth. The following therapeutic proposal was adapted: On the maxilla, a three-step procedure: first step: building of metal copings on 13, 16 and 26 and metal-ceramic crowns on 11 and 21, second step: building of telescop crowns on 16 and 26 and clasps on 13, 11 and 21, third step: casting of the removable partial denture framework and soldering to the telescop crowns and clasps. On the mandible, a provisional restoration using a supra-dental resin removable partial denture with ceramic occlusal surfaces was adopted. The aesthetic and functional

  11. Optimising the prescription of prosthetic technologies (opptec): Outcome measures for evidence based prosthetic practice and use

    LENUS (Irish Health Repository)

    Ryall, Dr Nicola

    2010-01-01

    This study provided a forum for patients and service providers to voice their opinions in what they believe to be the important predictors and outcomes involved in successful rehabilitation following limb loss. To develop a consensus on the most important outcomes and factors to address for both the lower limb and upper limb prosthetic prescription process, the above data relating to lower limb and upper prosthetics were subsequently used in the next phase of the research involving two Delphi surveys of 23 and 53 experts within the lower limb and upper limb amputation and prosthetic field respectively, including users, service providers and researchers.\\r\

  12. Mesofluidic controlled robotic or prosthetic finger

    Science.gov (United States)

    Lind, Randall F; Jansen, John F; Love, Lonnie J

    2013-11-19

    A mesofluidic powered robotic and/or prosthetic finger joint includes a first finger section having at least one mesofluidic actuator in fluid communication with a first actuator, a second mesofluidic actuator in fluid communication with a second actuator and a second prosthetic finger section pivotally connected to the first finger section by a joint pivot, wherein the first actuator pivotally cooperates with the second finger to provide a first mechanical advantage relative to the joint point and wherein the second actuator pivotally cooperates with the second finger section to provide a second mechanical advantage relative to the joint point.

  13. [Prosthetic rehabilitation: needs in Senegalese dental offices].

    Science.gov (United States)

    Mbodj, E B; Diouf, M; Faye, D; Ndiaye, A; Seck, M T; Ndiaye, C; Diallo, P D

    2011-12-01

    Knowledge of dental prosthetic needs will develop strategies for prevention and treatment through a package of individual, community and professional policies. The aim of this study was to evaluate prosthetic needs in Senegalese dental offices. The survey was conducted among people aged 15 years and more attending Senegalese dental clinics. The mean number of missing teeth was 4.4. Only 55.3% of the sample expressed the need for dentures and 81.8% had a diagnosed need for prosthesis. A statistically significant difference was noticed between the needs diagnosed and the expressed needs (p dental offices.

  14. Osseous scintigraphy and auxiliary graft

    International Nuclear Information System (INIS)

    Khelifa, F.; Siles, S.; Puech, B.

    1992-01-01

    The scintigraphy could be a good way to survey the osseous graft: three cases are studied in which were recognized the presence of a graft, surinfection, graft lysis, pseudo-arthrosis, algodystrophy. 8 refs., 5 figs

  15. Meniscal allograft transplantation. Part 1: systematic review of graft biology, graft shrinkage, graft extrusion, graft sizing, and graft fixation.

    Science.gov (United States)

    Samitier, Gonzalo; Alentorn-Geli, Eduard; Taylor, Dean C; Rill, Brian; Lock, Terrence; Moutzouros, Vasilius; Kolowich, Patricia

    2015-01-01

    To provide a systematic review of the literature regarding five topics in meniscal allograft transplantation: graft biology, shrinkage, extrusion, sizing, and fixation. A systematic literature search was conducted using the PubMed (MEDLINE), ScienceDirect, and EBSCO-CINAHL databases. Articles were classified only in one topic, but information contained could be reported into other topics. Information was classified according to type of study (animal, in vitro human, and in vivo human) and level of evidence (for in vivo human studies). Sixty-two studies were finally included: 30 biology, 3 graft shrinkage, 11 graft extrusion, 17 graft size, and 6 graft fixation (some studies were categorized in more than one topic). These studies corresponded to 22 animal studies, 22 in vitro human studies, and 23 in vivo human studies (7 level II, 10 level III, and 6 level IV). The principal conclusions were as follows: (a) Donor cells decrease after MAT and grafts are repopulated with host cells form synovium; (b) graft preservation alters collagen network (deep freezing) and causes cell apoptosis with loss of viable cells (cryopreservation); (c) graft shrinkage occurs mainly in lyophilized and gamma-irradiated grafts (less with cryopreservation); (d) graft extrusion is common but has no clinical/functional implications; (e) overall, MRI is not superior to plain radiograph for graft sizing; (f) graft width size matching is more important than length size matching; (g) height appears to be the most important factor influencing meniscal size; (h) bone fixation better restores contact mechanics than suture fixation, but there are no differences for pullout strength or functional results; and (i) suture fixation has more risk of graft extrusion compared to bone fixation. Systematic review of level II-IV studies, Level IV.

  16. PVDF multifilament yarns grafted with polystyrene induced by γ-irradiation: Influence of the grafting parameters on the mechanical properties

    International Nuclear Information System (INIS)

    Marmey, P.; Porte, M.C.; Baquey, Ch.

    2003-01-01

    The development of alternative prosthetic materials for cardiovascular applications has found growing interest due to the failure to date to be able to implement functional patent small diameter vascular grafts (diameter <5 mm). For instance, the successful implantation of small diameter polyester (PET) and expanded polytetrafluoroethylene (PTFEe) vascular grafts has not been achieved in humans. Our strategy is to work with a new multifilament yarns biomaterial, produced from polyvinylidene fluoride (PVDF), which shows suitable mechanical properties, such as a lower tensile modulus than PET and PTFEe. The required biological properties sought for (i.e. low thrombogenicity) could be achieved by 'heparin-like' surface modification treatments in order to modify the thrombogenicity levels of the polymeric materials [Ann. Biomed. Eng. 7 (1979) 429]. A four step method is necessary to achieve this 'heparin-like' surface transformation [J. Biomed. Mater. Res. 52 (2000) 119]. The first step consists in grafting polystyrene onto the PVDF surface by γ irradiation. The purpose of this study was to evaluate the influence of grafting parameters on the mechanical properties: (i) γ-ray irradiation time and (ii) grafting time of styrene monomers, which polymerize and form polystyrene bound to the PVDF surface

  17. Radiation-induced grafting of vinyl fluoride to polyacrylonitrile fibers

    International Nuclear Information System (INIS)

    Asamov, M.K.; Ziyaev, A.L.; Yul'chibaev, A.A.; Usmanov, Kh.U.

    1981-01-01

    Experimental data on gamma-radiation grafting of vinyl fluoride to polyacrylonitrile fibers in the presence of some organic liquids are given. It is shown, that the presence of chloroform vapours in the system produce sensitizing effect. Grafting of vinyl fluoride to polyacrylonitrile fibers considerably increases their thermal stability, lengthening and decreases shrinkage [ru

  18. Noradrenergic and cholinergic reinnervation of islet grafts in diabetic rats

    NARCIS (Netherlands)

    Houwing, H; VanAsperen, RM; VanderZee, EA; VanSuylichem, PTR; Oestreicher, AB; Steffens, AB; Strubbe, JH; Asperen, Roelie M. van

    1996-01-01

    Grafted islets become denervated due to the islet transplantation procedure. The aim of the present study was 1) to examine whether islet grafts in the liver, the spleen, and under the kidney capsule in rats become reinnervated following the transplantation and experimental procedures used in our

  19. 21 CFR 895.101 - Prosthetic hair fibers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic hair fibers. 895.101 Section 895.101 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES BANNED DEVICES Listing of Banned Devices § 895.101 Prosthetic hair fibers. Prosthetic hair...

  20. Comparative roll-over analysis of prosthetic feet

    NARCIS (Netherlands)

    Curtze, Carolin; Hof, At L.; van Keeken, Helco G.; Halbertsma, Jan P. K.; Postema, Klaas; Otten, Bert

    2009-01-01

    A prosthetic foot is a key element of a prosthetic leg, literally forming the basis for a stable and efficient amputee gait. We determined the roll-over characteristics of a broad range of prosthetic feet and examined the effect of a variety of shoes on these characteristics. The body weight of a

  1. A new computerized program for surveillance of prosthetic arteriovenous fistulas

    Directory of Open Access Journals (Sweden)

    Matteo Tozzi

    2015-05-01

    Full Text Available Stenosis and thrombosis are common causes of prosthetic vascular access (pVA failure. The role of arteriovenous fistula (AVF surveillance is widely debated. The aim of this paper is to present a new real-time application designed for AVF surveillance called SPIDER. Surgical staff and hemodialysis nurses are responsible for data entry. SPIDER automatically analyses data and generates alerts in case of abnormal trends. Surgical evaluation and duplex Doppler ultrasonography are then immediately performed to confirm presence of stenosis or other possible pVA defects. Surgery can be performed if required. A preliminary analysis of results will be completed at 12 months after the program begins and subsequently after 24 months. Primary assisted patency will be compared with historical using multivariate analysis. Expected results are an improvement in primary assisted pVA patency and reduction of hospitalizations. Simultaneous management of a high number of patients can become difficult due to the large amount of data required for surveillance. We want to demonstrate whether a real-time automated system could help to prevent thrombosis and graft loss.

  2. Advances in radiation grafting

    International Nuclear Information System (INIS)

    Hegazy, El-Sayed A.; AbdEl-Rehim, H.A.; Kamal, H.; Kandeel, K.A.

    2001-01-01

    Graft copolymerization is an attractive means for modifying base polymers because grafting frequently results in the superposition of properties relating to the backbone and pendent chains. Among the various methods for initiating the grafting reaction, ionizing radiation is the cleanest and most versatile method of grafting available. Ion-exchange membranes play an important role in modern technology, especially in separation and purification of materials. The search for improved membrane composition has considered almost every available polymeric material because of its great practical importance. Grafting of polymers with a mixture of monomers is important since different types of chains containing different functional groups are included. A great deal is focused on the waste treatment of heavy and toxic metals from wastewater because of the severe problems of environmental pollution. Functionalized polymers suitable for metal adsorption with their reactive functional groups such as carboxylic and pyridine groups suitable for waste treatment were prepared by radiation grafting method. More reactive chelating groups were further introduced to the grafted copolymer through its functional groups by chemical treatments with suitable reagents. The advances of radiation grafting and possible uses are briefly discussed

  3. Advances in radiation grafting

    Science.gov (United States)

    Hegazy, El-Sayed A.; AbdEl-Rehim, H. A.; Kamal, H.; Kandeel, K. A.

    2001-12-01

    Graft copolymerization is an attractive means for modifying base polymers because grafting frequently results in the superposition of properties relating to the backbone and pendent chains. Among the various methods for initiating the grafting reaction, ionizing radiation is the cleanest and most versatile method of grafting available. Ion-exchange membranes play an important role in modern technology, especially in separation and purification of materials. The search for improved membrane composition has considered almost every available polymeric material because of its great practical importance. Grafting of polymers with a mixture of monomers is important since different types of chains containing different functional groups are included. A great deal is focused on the waste treatment of heavy and toxic metals from wastewater because of the severe problems of environmental pollution. Functionalized polymers suitable for metal adsorption with their reactive functional groups such as carboxylic and pyridine groups suitable for waste treatment were prepared by radiation grafting method. More reactive chelating groups were further introduced to the grafted copolymer through its functional groups by chemical treatments with suitable reagents. The advances of radiation grafting and possible uses are briefly discussed.

  4. The effect of carbon dioxide therapy on composite graft survival.

    Science.gov (United States)

    Durães, Eliana Ferreira Ribeiro; Durães, Leonardo de Castro; Carneiro, Fabiana Pirani; Lino, Ruy de Souza; Sousa, João Batista de

    2013-08-01

    To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, histopathology features and histomorphometry of collagen. The treated group had a significantly lower weight gain (p=0.038). Histopathology was not significantly different between groups. There was an increase in amount of collagen in 2 cm grafts submitted to carbon dioxide therapy (p=0.003). Carboxytherapy didn't influence graft survival rate for 1.5 cm grafts or 2 cm grafts (p=0.567 and p=0.777, respectively). Carbon dioxide therapy increased the amount of collagen in 2 cm grafts. CO2 was not significantly different from saline infusion on composite grafts survival, but this study suggests that there is a mechanical effect caused by distension which favored graft survival.

  5. GRAFT TAKES OF TOMATO ON OTHER SOLANACEOUS PLANTS

    Directory of Open Access Journals (Sweden)

    ANDRÉ RICARDO ZEIST

    2017-01-01

    Full Text Available This paper aimed to assess tomato grafting on different solanaceous species through two grafting methods. Scions were cut from cultivar Santa Cruz Kada seedlings. A fully randomized experimental design was carried out with treatments in a 9 x 2 factorial scheme. As rootstocks, four accessions of mini - tomatoes (0224 - 53, RVTC 57, RVTC 20 and 6889 - 50 - Solanum lycopersicum L; two species of wild tomato ( Solanum habrochaites var hirsutum ‘PI - 127826’ and Solanum pennellii ‘LA716’; other two tomato species [ Solanum, cocona ( Solanum sessiliflorum and physalis ( Physalis peruviana ] and a control with cultivar Santa Cruz Kada (auto - graft rootstocks were used. In addition, two grafting methods were evaluated full cleft and approach graft. Fifteen days after grafting, plants were assessed for graft - take percentage; root length; plant height; leaf number; foliar area; root, stem and leaf dry matter; and ratio between shoot and root dry matter. Based on the results, we may state rootstock and grafting interaction had effect on both graft - take rate and plant development. Overall, the studied plants should be recommended as rootstock, except for 6889 - 50 mini - tomato ( S. lycopersicum L. and S. pennellii . Full cleft grafting was most suitable for cocona and physalis, while the approach method showed better results for the mini - tomato accessions 0224 - 53, RVTC 57 and RVTC 20, as well as for S. habrochaites .

  6. Mechanical and biological properties of the GORE-TEX expanded polytetrafluoroethylene (PTFE) prosthetic ligament.

    Science.gov (United States)

    Bolton, W; Bruchman, B

    1983-01-01

    Data from these studies have resulted in a modified implant technique which has taken into consideration the salient points from this and previous studies. Ongoing animal studies will provide a better understanding of the long-term performance of the material in the anterior cruciate ligament and medial collateral ligament positions. Additional studies will be implemented as new techniques and applications evolve. The key conclusions of this study are as follows: 1. This prosthetic ligament system is not intended to match the mechanical properties of the normal anterior cruciate ligament in dogs. However, in the dog at one to four months the GORE-TEX Prosthetic Ligament system is at least comparable in tensile strength to the repaired anterior cruciate ligament utilizing autogenous tissue at eight months. 2. One square knot with wire augmentation, appears to be an adequate method of fixation; however, since proximal placement of the knot will result in a mild bursitis formation, the implant technique has been modified so that the knot is placed more distally under the cranial tibial muscle. 3. The porosity of the material is adequate to allow for the tissue ingrowth, which is essential for fixation augmentation. 4. The recommended method of implantation appears to be crucial to satisfactory long-term performance of the device. Of particular importance, all edges of drill holes must be thoroughly radiused in order to minimize stress concentrations. 5. The GORE-TEX Prosthetic Ligament implanted in the anterior cruciate ligament position was effective in maintaining joint stability in the dog for up to four months. Ongoing studies have demonstrated maintenance of joint stability for up to ten months. 6. The limb need not be immobilized in order to assure healing and adequate fixation of the device. The immediate relative stability produced by the GORE-TEX Prosthetic Ligament system is adequate to encourage early mobilization. The only protection required is to allow

  7. Prosthetic soft contact lenses in Japan.

    Science.gov (United States)

    Kanemoto, Masumi; Toshida, Hiroshi; Takahiro, Itagaki; Murakami, Akira

    2007-11-01

    To investigate the use of the prosthetic iris-tinted soft contact lens, the SEED Opaque, during the past 5 years. The records of 42 outpatients (48 eyes) for whom the prosthetic soft contact lens was prescribed in the contact lens clinic of Juntendo University Hospital from July 2001 to June 2005 were investigated. An investigation was conducted in regard to the tint patterns of the prosthetic soft contact lens and the presence or absence of a transparent part in the middle, as a brown iris with a clear pupil or a solid pupil. The diagnosis, purpose of prescription, age when that lens was prescribed, complications, and changes in corrected visual acuities were analyzed retrospectively from the medical records. The mean age at the first prescription, total number of years of wearing prosthetic contact lenses, total number of prescriptions, and mean period to use each SEED Opaque lens were compared. The mean age at the first prescription of solid-pupil lens wearers was significantly younger than that for clear-pupil lens wearers (Ppossible to adjust the color and size of the cosmetic part and the pupil diameter. Further, corrected visual acuities could improve with the clear-pupil type for patients who had prescribed for improvement of visual function.

  8. Proceedings, 1972 Carahan Conference on Electronic Prosthetics.

    Science.gov (United States)

    Jackson, John S., Ed.; DeVore, R. William, Ed.

    Presented are 28 papers given at a 1972 conference on electronic prosthetics for the handicapped. Among the papers are the following titles: "Therapy for Cerebral Palsy Employing Artifician Sense Organs for Alternatives to Proprioceptive Feedback"; "Excessive Neuromuscular Time Delay as a Possible Cause of Poor Hand-Eye Coordination and…

  9. Consumer satisfaction in prosthetics and orthotics facilities

    NARCIS (Netherlands)

    Geertzen, J.H.B.; Gankema, H.G.J.; Groothoff, J.W.; Dijkstra, P.U.

    The aim of this study was to assess consumer/patient satisfaction with the services of the prosthetics and orthotics (P&O) facilities in the north of the Netherlands, using a modified SERVQUAL questionnaire. In this questionnaire, consumer interests and experiences are assessed on a 5-point Likert

  10. Prosthetic Management of Patients Presenting with Juvenile ...

    African Journals Online (AJOL)

    Eighteen were referred for prosthetic replacement. Their age ranged between 18 and 36 years. A total of 24 removable partial dentures were fabricated, 17[70.8%] were kennedy class III type, of which 11[64.7%] had the bounded saddle located in the anterior segment. Majority 8[44.4%] of the patients had 2-4 teeth replaced ...

  11. Mechanical behavior of provisional implant prosthetic abutments

    Science.gov (United States)

    Serra-Pastor, Blanca; Roig-Vanaclocha, Ana; Román-Rodriguez, Juan-Luis; Fons-Font, Antonio

    2015-01-01

    Introduction: Implant-supported prostheses have to overcome a major difficulty presented by the morphology and esthetics of peri-implant tissues in the anterior sector. Diverse therapeutic techniques are used for managing the mucosa adjacent to the implant and the most noteworthy is immediate/deferred fixed provisionalization. Objectives: In vitro testing of strength and deformation of implant prosthetic abutments made from different materials (Titanium/PEEK/methacrylate). Material and Methods: Forty Sweden&Martina® implant prosthetic abutments (n=40) were divided into five groups: Group MP: methacrylate provisional abutments with machined titanium base; Group PP: Poly ether ether ketone (PEEK) provisional abutments; Group TP: titanium provisional abutments; Group TAD: titanium anti-rotational definitive abutments; Group TRD: titanium rotational definitive abutments. Their mechanical behavior under static loading was analyzed. Samples were examined under a microscope to determine the type of fracture produced. Results and Conclusions: Definitive anti-rotational titanium abutments and definitive rotational titanium abutments achieved the best mean compression strength, while PEEK resin provisional abutments obtained the lowest. The group that showed the greatest elastic deformation was the group of titanium provisional abutments. Key words:Immediate loading, immediate provisionalization, implant prosthetic abutment, definitive implant prosthetic abutment. PMID:25129253

  12. Nonconventional mesocaval prosthetic shunt interposition in ...

    African Journals Online (AJOL)

    15 Burch PT, Kaza AK, Lambert LM, Holubkov R, Shaddy RE, Hawkins JA. Clinical performance of decellularized cryopreserved valved allografts compared with standard allografts in the right ventricular outflow tract. The Annals of thoracic surgery 2010; 90:1301–1306. Nonconventional mesocaval prosthetic shunt Salman ...

  13. Thoracoabdominal aneurysm repair using a four-branched thoracoabdominal graft: a case series.

    Science.gov (United States)

    Kokotsakis, John; Lazopoulos, George; Ashrafian, Hutan; Misthos, Panagiotis; Athanasiou, Thanos; Lioulias, Achilleas

    2009-07-17

    Revascularization of the visceral arteries during thoracoabdominal aneurysm repair is usually performed sequentially by an anastomosis between a prosthetic graft and an aortic patch. There are immediate operative risks such as bleeding and distortion. In the longer term, aneurysm, pseudo-aneurysm and rupture may occur. These require reoperation and are associated with significant morbidity and mortality.We present our experience with Crawford IV thoracoabdominal aneurysm repair in four patients, using a prefabricated four-branched graft (Coselli graft). At two years there were no deaths, no complications and no vessel abnormalities on computed tomography. We recommend its use as the graft of choice in young patients with an aortic tissue disorder requiring total resection of the aortic wall at the level of the visceral vessels.

  14. Prosthetic vision: devices, patient outcomes and retinal research.

    Science.gov (United States)

    Hadjinicolaou, Alex E; Meffin, Hamish; Maturana, Matias I; Cloherty, Shaun L; Ibbotson, Michael R

    2015-09-01

    Retinal disease and its associated retinal degeneration can lead to the loss of photoreceptors and therefore, profound blindness. While retinal degeneration destroys the photoreceptors, the neural circuits that convey information from the eye to the brain are sufficiently preserved to make it possible to restore sight using prosthetic devices. Typically, these devices consist of a digital camera and an implantable neurostimulator. The image sensor in a digital camera has the same spatiotopic arrangement as the photoreceptors of the retina. Therefore, it is possible to extract meaningful spatial information from an image and deliver it via an array of stimulating electrodes directly to the surviving retinal circuits. Here, we review the structure and function of normal and degenerate retina. The different approaches to prosthetic implant design are described in the context of human and preclinical trials. In the last section, we review studies of electrical properties of the retina and its response to electrical stimulation. These types of investigation are currently assessing a number of key challenges identified in human trials, including stimulation efficacy, spatial localisation, desensitisation to repetitive stimulation and selective activation of retinal cell populations. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

  15. GRAFT COPOLYMERIZATION OF OLYGOESTERACRYLATES WITH LIQUID RUBBER AND COPOLYMER’S CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Y. A. Anisimov

    2015-02-01

    Full Text Available The kinetic of graft copolymerization of threeethyleneglicoldimethacrylate and di threeethyleneglicolftalatedimethacrylate with liquid buthadiene rubber have been studied as a function of the olygomers composition. The experimental constants of copolymerization rate and efficiency olygoesteracrylates graft to liquid rubber were determined. The ihfluence of olygoesteracrylates’ nature on the grafting efficiency to olygomer rubber is determined and the strength characteristics are found.

  16. Pregnancy after Prosthetic Aortic Valve Replacement: How Do We Monitor Prosthetic Valvular Function during Pregnancy?

    Directory of Open Access Journals (Sweden)

    Nicole Sahasrabudhe

    2018-01-01

    Full Text Available Background. With modern medicine, many women after structural heart repair are deciding to experience pregnancy. There is a need for further study to identify normal echocardiographic parameters to better assess prosthetic valvular function in pregnancy. In addition, a multidisciplinary approach is essential in managing pregnant patients with complex cardiac conditions. Case. A 22-year-old nulliparous woman with an aortic valve replacement 18 months prior to her pregnancy presented to prenatal care at 20-week gestation. During her prenatal care, serial echocardiography showed a significant increase in the mean gradient across the prosthetic aortic valve. Multidisciplinary management and a serial echocardiography played an integral role in her care that resulted in a successful spontaneous vaginal delivery without complications. Conclusion. Further characterization of the normal echocardiographic parameters in pregnant patients with prosthetic valves is critical to optimize prenatal care for this patient population. This case report is novel in that serial echocardiograms were obtained throughout prenatal care, which showed significant changes across the prosthetic aortic valve. Teaching Points. (1 Further study is needed to identify normal echocardiographic parameters to best assess prosthetic valvular function in pregnancy. (2 Multidisciplinary management is encouraged to optimize prenatal care for women with prosthetic aortic valve replacements.

  17. Art Practice as Prosthetic Visuality

    Science.gov (United States)

    Garoian, Charles R.

    2010-01-01

    In this lecture I explore and conceptualize the anomalous spaces of perception and memory in art practice and research where experimental and alternative discourses and pedagogies can emerge. I argue that the instabilities and slippages between what is visible and invisible, known and unknown, in these spaces enable insightful and multivalent ways…

  18. Magnetic Oculomotor Prosthetics for Acquired Nystagmus.

    Science.gov (United States)

    Nachev, Parashkev; Rose, Geoff E; Verity, David H; Manohar, Sanjay G; MacKenzie, Kelly; Adams, Gill; Theodorou, Maria; Pankhurst, Quentin A; Kennard, Christopher

    2017-10-01

    Acquired nystagmus, a highly symptomatic consequence of damage to the substrates of oculomotor control, often is resistant to pharmacotherapy. Although heterogeneous in its neural cause, its expression is unified at the effector-the eye muscles themselves-where physical damping of the oscillation offers an alternative approach. Because direct surgical fixation would immobilize the globe, action at a distance is required to damp the oscillation at the point of fixation, allowing unhindered gaze shifts at other times. Implementing this idea magnetically, herein we describe the successful implantation of a novel magnetic oculomotor prosthesis in a patient. Case report of a pilot, experimental intervention. A 49-year-old man with longstanding, medication-resistant, upbeat nystagmus resulting from a paraneoplastic syndrome caused by stage 2A, grade I, nodular sclerosing Hodgkin's lymphoma. We designed a 2-part, titanium-encased, rare-earth magnet oculomotor prosthesis, powered to damp nystagmus without interfering with the larger forces involved in saccades. Its damping effects were confirmed when applied externally. We proceeded to implant the device in the patient, comparing visual functions and high-resolution oculography before and after implantation and monitoring the patient for more than 4 years after surgery. We recorded Snellen visual acuity before and after intervention, as well as the amplitude, drift velocity, frequency, and intensity of the nystagmus in each eye. The patient reported a clinically significant improvement of 1 line of Snellen acuity (from 6/9 bilaterally to 6/6 on the left and 6/5-2 on the right), reflecting an objectively measured reduction in the amplitude, drift velocity, frequency, and intensity of the nystagmus. These improvements were maintained throughout a follow-up of 4 years and enabled him to return to paid employment. This work opens a new field of implantable therapeutic devices-oculomotor prosthetics-designed to modify eye

  19. Tissue response and wound healing after placement of two types of bioengineered grafts containing vital cells in submucosal maxillary pouches: an experimental pilot study in rabbits.

    Science.gov (United States)

    Bornstein, Michael M; Reichart, Peter A; Buser, Daniel; Bosshardt, Dieter D

    2011-01-01

    This pilot study evaluated the wound healing and tissue response after placement of two different skin substitutes in subgingival mucosal pouches in rabbits. Four rabbits were selected to receive a commercially available skin substitute consisting of a collagen matrix with fibroblasts and an epithelial layer (test membrane 1) and a prototype device consisting of a collagen matrix with fibroblasts only (test membrane 2). In each rabbit, two horizontal incisions were made in the buccal alveolar mucosa of the maxilla bilaterally to create submucosal pouches. Three pouches in each animal were filled with either the test 1 or test 2 membranes, and one pouch was left without a membrane (sham-operated control). All rabbits were sacrificed after a healing period of 4 weeks, and histologic samples were prepared and examined. After a healing period of 1 month, both tested membranes were still visible in the sections. Test membrane 1 was still bilayered, contained inflammatory cells in its center, and was encapsulated by a thick fibrous tissue. Numerous ectopic calcifications were evident in the collagenous part of the membrane and in association with some basal epithelial cells. Test membrane 2 was also encapsulated in fibrous tissue, with inflammatory cells present only between the fibrous encapsulation and the remnants of the membrane. For test membrane 2, no calcifications were visible. Test membrane 1 seemed to be more resistant to degradation, but there was also a more pronounced inflammatory reaction in comparison to test membrane 2, especially in the vicinity of the keratinocytes. The significance of the ectopic calcifications, along with that of the resorption or degradation processes of both tested membranes, must be evaluated in future experimental studies, with different time points after implantation examined.

  20. Bone Graft Alternatives

    Science.gov (United States)

    ... spinal deformity, or who have some types of disc herniations. In certain types of spinal fusion, bone grafts ... Specialist SEARCH Download Brochure ENGLISH Related Treatments Cervical Disc Herniation Fusion Lumbar Disc Herniation {1} ##LOC[OK]## {1} ## ...

  1. Melting graft wound syndrome

    Directory of Open Access Journals (Sweden)

    Shiou-Mei Chen

    2017-09-01

    Full Text Available Melting graft wound syndrome is characterized by progressive epidermal loss from a previously well-taken skin graft, healed burn, or donor site. It may result in considerable morbidity and require prolonged treatment. We report a 23-year-old flame-burned patient with second- to third-degree burns involving more than 70% of the total body surface area, whose condition was complicated with septic shock. The patient presented with erosions and ulcers occurring on previously well-taken skin graft recipient sites over both legs and progressive epidermal loss on donor sites over the back. The patient's presentation was compatible with the diagnosis of melting graft wound syndrome, and we successfully treated the patient with debridement and supportive treatment.

  2. Prosthetic rehabilitation of an amputated finger

    Directory of Open Access Journals (Sweden)

    Meenu Garg

    2016-01-01

    Full Text Available Amputation of finger causes devastating physical, psychosocial, and economic damage to an individual. The concealment of an amputated part with the help of prosthesis can shield an amputee from social stigma. Prosthesis for such patient must be comfortable to wear lightweight, durable, cosmetically pleasing easy to put on and remove. The restoration of finger amputations depends on the amount of tissue involved, the involvement of bone, the angles and levels of amputation, and the involvement of other fingers. The microsurgical reimplantation helps to save many severely injured and traumatically amputed finger. The prosthetic rehabilitation of an amputated finger is considered when microvascular reconstruction is not possible, unavailable, unsuccessful, or unaffordable. Most accepted material is silicones because of their better esthetics, ease of manipulation, and availability. This paper presents prosthetic rehabilitation of index finger of the right hand with custom made silicon prosthesis.

  3. Targeted muscle reinnervation and advanced prosthetic arms.

    Science.gov (United States)

    Cheesborough, Jennifer E; Smith, Lauren H; Kuiken, Todd A; Dumanian, Gregory A

    2015-02-01

    Targeted muscle reinnervation (TMR) is a surgical procedure used to improve the control of upper limb prostheses. Residual nerves from the amputated limb are transferred to reinnervate new muscle targets that have otherwise lost their function. These reinnervated muscles then serve as biological amplifiers of the amputated nerve motor signals, allowing for more intuitive control of advanced prosthetic arms. Here the authors provide a review of surgical techniques for TMR in patients with either transhumeral or shoulder disarticulation amputations. They also discuss how TMR may act synergistically with recent advances in prosthetic arm technologies to improve prosthesis controllability. Discussion of TMR and prosthesis control is presented in the context of a 41-year-old man with a left-side shoulder disarticulation and a right-side transhumeral amputation. This patient underwent bilateral TMR surgery and was fit with advanced pattern-recognition myoelectric prostheses.

  4. The radiology of prosthetic heart valves

    International Nuclear Information System (INIS)

    Steiner, R.M.; Flicker, S.

    1985-01-01

    The development of prosthetic heart valves in the late 1950s ushered in a new era in the treatment of heart disease. The radiologist has an important role to play preoperatively in the diagnosis of valvular heart disease. Radiology is valuable in identification of the implanted prosthetic valve and recognition of complications associated with valve implantation. Radiologists must be familiar with the imaging techniques best suited to evaluate the function of the valve prosthesis in question. In this chapter the authors discuss the radiographic approach to the evaluation of the status of patients for valve replacement and the imaging problems peculiar to the types of valves in current use. The relative value of plain-film radiography, fluoroscopy, videorecording and cinerecording, and aortography is addressed, as well as the potential value of magnetic resonance imaging and subsecond dynamic computed tomography

  5. Characteristics of a volume-adjustable compression chamber for transradial prosthetic interface.

    Science.gov (United States)

    Sang, Yuanjun; Li, Xiang; Luo, Yun

    2016-07-01

    In the transradial limb-socket contact interface, the physiological properties and prosthetic operating habits of the residual limb might affect the comfort and functionality of the prosthesis. To enhance the comfort and functionality of the interface, a frame-type socket with four volume-adjustable compression chambers was proposed for the transradial amputation level. The contact pressure of the limb-socket interface was adjusted by the volume changes in the chambers and controlled by a vacuum pump and the corresponding control system. The parameters of the chamber were designed in accordance with the biomechanics of the forearm soft tissue. The chamber with a negative stiffness characteristic was theoretically compared with the chamber with a positive stiffness characteristic. The results showed that the former had a superior performance to the latter in safety and pump performance requirements. A physical model of the transradial frame-type prosthetic interface was also manufactured with four negative stiffness chambers. The experimental results showed that this new prosthetic interface achieved more fitting time and better performance in comfort and functionality than the fixed frame-type socket. This new prosthetic interface with volume-adjustable compression chambers might be an alternative choice for transradial amputees. © IMechE 2016.

  6. Matching prosthetics order records in VA National Prosthetics Patient Database to healthcare utilization databases.

    Science.gov (United States)

    Smith, Mark W; Su, Pon; Phibbs, Ciaran S

    2010-01-01

    The National Prosthetics Patient Database (NPPD) is the national Department of Veterans Affairs (VA) dataset that records characteristics of individual prosthetic and assistive devices. It remains unknown how well NPPD records can be matched to encounter records for the same individuals in major VA utilization databases. We compared the count of prosthetics records in the NPPD with the count of prosthetics-related procedures for the same individuals recorded in major VA utilization databases. We then attempted to match the NPPD records to the utilization records by person and date. In general, 40% to 60% of the NPPD records could be matched to outpatient utilization records within a 14-day window around the NPPD dataset entry date. Match rates for inpatient data were lower: 10% to 16% within a 14-day window. The NPPD will be particularly important for studies of certain veteran groups, such as those with spinal cord injury or blast-related polytraumatic injury. Health services researchers should use both the NPPD and utilization databases to develop a full understanding of prosthetics use by individual patients.

  7. Retinal prosthetics, optogenetics, and chemical photoswitches.

    Science.gov (United States)

    Marc, Robert; Pfeiffer, Rebecca; Jones, Bryan

    2014-10-15

    Three technologies have emerged as therapies to restore light sensing to profoundly blind patients suffering from late-stage retinal degenerations: (1) retinal prosthetics, (2) optogenetics, and (3) chemical photoswitches. Prosthetics are the most mature and the only approach in clinical practice. Prosthetic implants require complex surgical intervention and provide only limited visual resolution but can potentially restore navigational ability to many blind patients. Optogenetics uses viral delivery of type 1 opsin genes from prokaryotes or eukaryote algae to restore light responses in survivor neurons. Targeting and expression remain major problems, but are potentially soluble. Importantly, optogenetics could provide the ultimate in high-resolution vision due to the long persistence of gene expression achieved in animal models. Nevertheless, optogenetics remains challenging to implement in human eyes with large volumes, complex disease progression, and physical barriers to viral penetration. Now, a new generation of photochromic ligands or chemical photoswitches (azobenzene-quaternary ammonium derivatives) can be injected into a degenerated mouse eye and, in minutes to hours, activate light responses in neurons. These photoswitches offer the potential for rapidly and reversibly screening the vision restoration expected in an individual patient. Chemical photoswitch variants that persist in the cell membrane could make them a simple therapy of choice, with resolution and sensitivity equivalent to optogenetics approaches. A major complexity in treating retinal degenerations is retinal remodeling: pathologic network rewiring, molecular reprogramming, and cell death that compromise signaling in the surviving retina. Remodeling forces a choice between upstream and downstream targeting, each engaging different benefits and defects. Prosthetics and optogenetics can be implemented in either mode, but the use of chemical photoswitches is currently limited to downstream

  8. Control system and method for prosthetic devices

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor)

    1992-01-01

    A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the movable body part through the full-shrug position of the movable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the movable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective movable prosthesis device and its sub-prosthesis.

  9. New developments in prosthetic arm systems

    Directory of Open Access Journals (Sweden)

    Vujaklija I

    2016-07-01

    Full Text Available Ivan Vujaklija,1 Dario Farina,1 Oskar C Aszmann2 1Institute of Neurorehabilitation Systems, Bernstein Focus Neurotechnology Göttingen, University Medical Center Göttingen, Georg-August University, Göttingen, Germany; 2Christian Doppler Laboratory for Restoration of Extremity Function, Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria Abstract: Absence of an upper limb leads to severe impairments in everyday life, which can further influence the social and mental state. For these reasons, early developments in cosmetic and body-driven prostheses date some centuries ago, and they have been evolving ever since. Following the end of the Second World War, rapid developments in technology resulted in powered myoelectric hand prosthetics. In the years to come, these devices were common on the market, though they still suffered high user abandonment rates. The reasons for rejection were trifold – insufficient functionality of the hardware, fragile design, and cumbersome control. In the last decade, both academia and industry have reached major improvements concerning technical features of upper limb prosthetics and methods for their interfacing and control. Advanced robotic hands are offered by several vendors and research groups, with a variety of active and passive wrist options that can be articulated across several degrees of freedom. Nowadays, elbow joint designs include active solutions with different weight and power options. Control features are getting progressively more sophisticated, offering options for multiple sensor integration and multi-joint articulation. Latest developments in socket designs are capable of facilitating implantable and multiple surface electromyography sensors in both traditional and osseointegration-based systems. Novel surgical techniques in combination with modern, sophisticated hardware are enabling restoration of dexterous upper limb

  10. Targeted Muscle Reinnervation and Advanced Prosthetic Arms

    OpenAIRE

    Cheesborough, Jennifer E.; Smith, Lauren H.; Kuiken, Todd A.; Dumanian, Gregory A.

    2015-01-01

    Targeted muscle reinnervation (TMR) is a surgical procedure used to improve the control of upper limb prostheses. Residual nerves from the amputated limb are transferred to reinnervate new muscle targets that have otherwise lost their function. These reinnervated muscles then serve as biological amplifiers of the amputated nerve motor signals, allowing for more intuitive control of advanced prosthetic arms. Here the authors provide a review of surgical techniques for TMR in patients with eith...

  11. Wettability of silicone rubber maxillofacial prosthetic materials.

    Science.gov (United States)

    Waters, M G; Jagger, R G; Polyzois, G L

    1999-04-01

    Maxillofacial prosthetic materials that contact skin or mucosa should have good wettability. A material that is easily wetted will form a superior lubricating layer between the supporting tissues and, thus, reduce friction and patient discomfort. The surface energy of a maxillofacial prosthetic material will give an indication of the amount of energy available for adhesion and of the susceptibility of the material to bacterial adhesion. This study evaluated the wettability and surface energies of a range of commercially available silicone rubber maxillofacial prosthetic materials. Contact angles and surface energies were measured by using a dynamic contact angle measuring technique. Four commonly used silicone maxillofacial materials were tested and their properties compared with those of an acrylic resin denture base material and a widely used denture soft lining material. There were no significant differences in the wettability of the silicone rubber materials. All materials were significantly less wetted than the denture acrylic resin material. There were no significant differences in the surface energies of the silicone rubber materials, but all were significantly lower than denture acrylic resin material. The Cahn dynamic contact angle analyzer was a quick and reproducible method for determining the contact angles and surface energies of maxillofacial materials. Further work is needed to improve the wettability of silicone rubber materials used for maxillofacial prostheses, thus, reducing their potential to produce friction with tissues.

  12. Adaptive sports technology and biomechanics: prosthetics.

    Science.gov (United States)

    De Luigi, Arthur Jason; Cooper, Rory A

    2014-08-01

    With the technologic advances in medicine and an emphasis on maintaining physical fitness, the population of athletes with impairments is growing. It is incumbent upon health care practitioners to make every effort to inform these individuals of growing and diverse opportunities and to encourage safe exercise and athletic participation through counseling and education. Given the opportunities for participation in sports for persons with a limb deficiency, the demand for new, innovative prosthetic designs is challenging the clinical and technical expertise of the physician and prosthetist. When generating a prosthetic prescription, physicians and prosthetists should consider the needs and preferences of the athlete with limb deficiency, as well as the functional demands of the chosen sporting activity. The intent of this article is to provide information regarding the current advancements in the adaptive sports technology and biomechanics in the field of prosthetics, and to assist clinicians and their patients in facilitating participation in sporting activities. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  13. Comparison of FLIXENE™ and standard PTFE arteriovenous graft for early haemodialysis.

    Science.gov (United States)

    Chiang, Nathaniel; Hulme, Katherine Ria; Haggart, Paul Charles; Vasudevan, Thodur

    2014-01-01

    The purpose is to compare the outcomes of FLIXENE™ arteriovenous graft (AVG) to standard polytetrafluoroethylene (PTFE) AVG for early haemodialysis. This is a prospective observational study of all AVGs placed over a 40-month period between 2008 and 2011 at our vascular unit. Primary outcome was to examine early cannulation rates for FLIXENE™. Secondary outcomes included patency rates, usability of grafts, complications in particular infections, interventions and death in comparison to standard PTFE grafts. Forty-five FLIXENE™ and 19 standard PTFE AVGs were placed in the study period; 89% of FLIXENE™ grafts were used for dialysis, with 78% cannulated within 3 days. At 18 months, primary patency (FLIXENE™ 34% vs standard PTFE 24%), primary assisted patency (35% vs 36%) and secondary patency rate (51% vs 48%) were not statistically different; 20.2% of FLIXENE™ grafts were infected at 18 months requiring explantation compared with 40.3% of standard PTFE grafts (p=0.14). FLIXENE™ can be cannulated for dialysis within 3 days. It has similar patency and complication rates as other prosthetic grafts in the market. In patients who have no access and require urgent dialysis, FLIXENE™ is a viable option.

  14. Prosthetic mesh repair of abdominal wall hernias in horses.

    Science.gov (United States)

    Tóth, Ferenc; Schumacher, Jim

    2018-02-05

    Repair of hernias of the abdominal wall of horses is often augmented by inserting a prosthetic mesh. In this review, we describe the various characteristics of prosthetic meshes used for hernia repair and present 2 systems that are used by surgeons in the human medical field to classify techniques of prosthetic mesh herniorrhaphy. Both of these classification systems distinguish between onlay, inlay, sublay, and underlay placements of mesh, based on the location within the abdominal wall in which the prosthetic mesh is inserted. We separate the published techniques of prosthetic mesh herniorrhaphy of horses using this classification system, ascribing names to the techniques of herniorrhaphy where none existed, and report the success rates and complications associated with each technique. By introducing a classification system widely used in the human medical field and illustrating each technique in a figure, we hope to clarify inconsistent nomenclature associated with prosthetic mesh herniorrhaphy performed by veterinary surgeons. © 2018 The American College of Veterinary Surgeons.

  15. Studies on the properties of poly (ethylene oxide) R-150 hydrogel films formed by irradiation graft

    International Nuclear Information System (INIS)

    Yang Zhanshan; Zhu Nankang; Yang Shuqin; Qiang Yizhong

    1999-01-01

    In order to improve the mechanical properties of poly (ethylene oxide) (PEO) hydrogel film was used as wound dressing. The chemical and physical properties of the PEO R-150 graft hydrogel film formed by blends of electron beam irradiated-PEO R-150 and poly(vinyl alcohol) (PVA) were studied. The experimental results showed that the crosslinking densities of the PEO R-150 graft hydrogel increased along with the increasing of the irradiation doses and decreased with the increasing of the blend concentrations. While the PVA graft proportions did not produce obvious effects on the crosslinking density of the graft hydrogel. The crosslinking density of the graft hydrogel were obviously lower than that of the pure PVA hydrogel. The equilibrium water content of the graft hydrogel decrease as the irradiation dose and the PVA graft proportion increased; but they increased as the blend concentration increased. The equilibrium water content of the graft hydrogel was obviously higher than those of the pure PVA hydrogel. The hardness of the PVA hydrogel film increased with the irradiation dose. The hardness of the graft hydrogel decreased with the blend concentration, whereas it increased with the PVA graft proportion. The results suggest the PVA produces a main effect on the crosslinking density of the graft hydrogel, the PEO R-150 produces a main effect on the equilibrium water content of the graft hydrogel, and the both polymers have double effects on the hardness of the graft hydrogel

  16. Fused Filament Fabrication of Prosthetic Components for Trans-Humeral Upper Limb Prosthetics

    Science.gov (United States)

    Lathers, Steven M.

    Presented below is the design and fabrication of prosthetic components consisting of an attachment, tactile sensing, and actuator systems with Fused Filament Fabrication (FFF) technique. The attachment system is a thermoplastic osseointegrated upper limb prosthesis for average adult trans-humeral amputation with mechanical properties greater than upper limb skeletal bone. The prosthetic designed has: a one-step surgical process, large cavities for bone tissue ingrowth, uses a material that has an elastic modulus less than skeletal bone, and can be fabricated on one system. FFF osseointegration screw is an improvement upon the current two-part osseointegrated prosthetics that are composed of a fixture and abutment. The current prosthetic design requires two invasive surgeries for implantation and are made of titanium, which has an elastic modulus greater than bone. An elastic modulus greater than bone causes stress shielding and overtime can cause loosening of the prosthetic. The tactile sensor is a thermoplastic piezo-resistive sensor for daily activities for a prosthetic's feedback system. The tactile sensor is manufactured from a low elastic modulus composite comprising of a compressible thermoplastic elastomer and conductive carbon. Carbon is in graphite form and added in high filler ratios. The printed sensors were compared to sensors that were fabricated in a gravity mold to highlight the difference in FFF sensors to molded sensors. The 3D printed tactile sensor has a thickness and feel similar to human skin, has a simple fabrication technique, can detect forces needed for daily activities, and can be manufactured in to user specific geometries. Lastly, a biomimicking skeletal muscle actuator for prosthetics was developed. The actuator developed is manufactured with Fuse Filament Fabrication using a shape memory polymer composite that has non-linear contractile and passive forces, contractile forces and strains comparable to mammalian skeletal muscle, reaction

  17. Stiffness and hysteresis properties of some prosthetic feet

    OpenAIRE

    van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the hysteresis, which are the topics of this paper, are not properly prescribed, but could be adapted to improve the prosthetic walking performance. The shape is strongly related to the cosmetic appearance a...

  18. Axillobifemoral bypass grafting

    Directory of Open Access Journals (Sweden)

    Davidović Lazar B.

    2004-01-01

    Full Text Available INTRODUCTION Axillo-femoral bypass (AxF means connecting the axillar and femoral artery with the graft that is placed subcutaneously [1]. Usually, this graft is connected with contralateral femoral artery via one accessory subcutaneous graft, and this connection is known as axillobifemoral bypass (AxFF. This extra-anatomic procedure is an alternative method to the standard reconstruction of aortoiliac region when there are contraindications for general or local reasons. OBJECTIVE The objective of this paper is to show early and late results of AxFF bypass grafting as well as to show the indications for AxFF bypass. METHODS The sample consisted of 37 patients. The procedure was performed in 28 patients who suffered from aortoiliac occlusive disease and who were at high risk due to the comorbidity- in one patient with the rupture of juxtarenal aneurysm of abdominal aorta; in five patients with aortoenteric fistula, in two patients with iatrogenic lesion of abdominal aorta and in one female patient with anus preternaturalis definitivus who was treated for rectovaginal fistula. Donor's right axillary artery was used in 26 cases (70.3%, and donor's left axillary artery was used in 9 cases (29.7%. Dacron graft was used in 34 patients and Polytetrafluo-roethlylene graft was used in three patients. Simultaneously, profundo-plastic was done in four patients and femoro-popliteal bypass was performed in three patients. In five patients who suffered from aortoenteric fistula, simultaneous intervention of gastrointerstinal system has been done, x2 test was used for statistical evaluation and life table method was used for verification of late graft patency. RESULTS The rate of early postoperative mortality was 13.5%. The causes of death were: sepsis -1, MOFS - 3, and infarct myocardium -1. The mean follow up period was 40.1 months, ranging from six months to 17 years. During the follow up period, an early graft thrombosis was identified in two and late graft

  19. In vitro study of biofilm growth on biologic prosthetics.

    Science.gov (United States)

    Bellows, Charles; Smith, Alison

    2014-01-01

    Biologic prosthetics are increasingly used for the repair of abdominal wall hernia defects but can become infected as a result of peri- or early post-operative bacterial contamination. Data evaluating biofilm formation on biologic prosthetics is lacking. The aim of this study was to investigate the influence of different biologic prosthetics on the growth behavior of two different bacterial species and their ability to form biofilms. Methicillin resistant Staphylococcus aureus (MRSA) or Pseudomrnonas aeruginosa were incubated on disks of two biologic prosthetics-human acellular dermis (ADM), and porcine small intestinal submucosa (SIS). The bacteria were allowed to attach to the prosthetics and propagate into mature biofilms for 24 hours at 370C. Images of biofilms were obtained using confocal microscopy and scanning electron microscopy (SEM). The number of viable cells and the biofilm biomass were quantified by colony forming units (CFUs) and crystal violet staining respectively. Analysis of variance was performed to compare the mean values for the different prosthetics. Each biologic matrix had a distinct surface characteristic. SEM visualized mature biofilms characterized by highly organized multi-cellular structures on surface of both biologic prosthetics. Quantification of bacterial growth over time showed that ADM had the lowest CFUs and biofilm biomass at 24 hours post-inoculation compared to SIS for both bacterial strains. MRSA and P. aeruginosa can form mature biofilms on biologic prosthetics but the relative abundance of the biofilm varies on different prosthetic constructs. Biologic material composition and manufacturing methods may influence bacterial adherence.

  20. The role of osteoblasts in peri-prosthetic osteolysis.

    LENUS (Irish Health Repository)

    O'Neill, S C

    2013-08-01

    Peri-prosthetic osteolysis and subsequent aseptic loosening is the most common reason for revising total hip replacements. Wear particles originating from the prosthetic components interact with multiple cell types in the peri-prosthetic region resulting in an inflammatory process that ultimately leads to peri-prosthetic bone loss. These cells include macrophages, osteoclasts, osteoblasts and fibroblasts. The majority of research in peri-prosthetic osteolysis has concentrated on the role played by osteoclasts and macrophages. The purpose of this review is to assess the role of the osteoblast in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts and contribute to the osteolytic process by two mechanisms. First, particles and metallic ions have been shown to inhibit the osteoblast in terms of its ability to secrete mineralised bone matrix, by reducing calcium deposition, alkaline phosphatase activity and its ability to proliferate. Secondly, particles and metallic ions have been shown to stimulate osteoblasts to produce pro inflammatory mediators in vitro. In vivo, these mediators have the potential to attract pro-inflammatory cells to the peri-prosthetic area and stimulate osteoclasts to absorb bone. Further research is needed to fully define the role of the osteoblast in peri-prosthetic osteolysis and to explore its potential role as a therapeutic target in this condition.

  1. Factors Associated with Prosthetic Looseness in Lower Limb Amputees.

    Science.gov (United States)

    Phonghanyudh, Thong; Sutpasanon, Taweesak; Hathaiareerug, Chanasak; Devakula, M L Buddhibongsa; Kumnerddee, Wipoo

    2015-12-01

    To determine the factors associated with prosthetic looseness in lower limb amputees in Sisaket province. The present was a cross-sectional descriptive study. Subjects were lower limb amputees who previously obtained prostheses and required prosthetic replacements at the mobile prosthetic laboratory unit under the Prostheses Foundation of H.R.H. the Princess Mother at Khun Han Hospital, Sisaket province, in February 2013. Data including participant characteristics, prosthetic looseness data, and various variables were collected by direct semi-structured interview. Energy expenditures in physical activities were measured using the Thai version of the short format international physical activity questionnaire. Data between participants with and without prosthetic looseness were compared to determine prosthetic loosening associated factors. Among 101 participants enrolled, 33 (32.7%) had prosthetic looseness with average onset of 1.76 ± 1.67 years. Diabetes mellitus was the only significant factor associated with prosthetic looseness from both univariate and multivariate analyses (HR = 7.05, p = 0.002 and HR = 5.93, p = 0.007 respectively). Among the lower limb amputees in Sisaket province, diabetes mellitus was the only factor associated with prosthetic looseness. Therefore, diabetic screening should be supplemented in lower limb amputee assessment protocol. In addition, we recommend that amputees with diabetes mellitus should receive prosthesis check out at approximately

  2. Echocardiographic Evaluation of Tricuspid Prosthetic Valves: An Update

    Directory of Open Access Journals (Sweden)

    Dimitrios Maragiannis, MD, FASE, FACC

    2016-05-01

    Full Text Available This review focuses on the diagnostic value of novel echocardiographic techniques and the clinical application of recently described algorithms to assess tricuspid prosthetic valve function.

  3. Successful Management of Prosthetic Valve Brucella Endocarditis with Antibiotherapy Alone

    Directory of Open Access Journals (Sweden)

    José Pedro Fonseca

    2018-01-01

    Full Text Available Objectives: To report a case of mechanical aortic prosthesis Brucella endocarditis successfully treated with antibiotics alone. Materials and methods: We describe a clinical case and present a review of the literature. Results: A 60-year-old female farmer with a mechanical aortic prosthetic valve presented with low back pain and fever. She was diagnosed with prosthetic valve Brucella mellitensis endocarditis and was cured with antibiotic therapy alone. Few cases of successfully treated prosthetic valve Brucella endocarditis without surgery have been reported. Conclusion: Prosthetic valve Brucella endocarditis usually requires surgical valve replacement. However, selected patients may be successfully treated with antibiotic therapy alone.

  4. Grafts for Ridge Preservation

    Science.gov (United States)

    Jamjoom, Amal; Cohen, Robert E.

    2015-01-01

    Alveolar ridge bone resorption is a biologic phenomenon that occurs following tooth extraction and cannot be prevented. This paper reviews the vertical and horizontal ridge dimensional changes that are associated with tooth extraction. It also provides an overview of the advantages of ridge preservation as well as grafting materials. A Medline search among English language papers was performed in March 2015 using alveolar ridge preservation, ridge augmentation, and various graft types as search terms. Additional papers were considered following the preliminary review of the initial search that were relevant to alveolar ridge preservation. The literature suggests that ridge preservation methods and augmentation techniques are available to minimize and restore available bone. Numerous grafting materials, such as autografts, allografts, xenografts, and alloplasts, currently are used for ridge preservation. Other materials, such as growth factors, also can be used to enhance biologic outcome. PMID:26262646

  5. [Chickenpox, burns and grafts].

    Science.gov (United States)

    Rojas Zegers, J; Fidel Avendaño, L

    1979-01-01

    An outbreak of chickenpox that occurred at the Burns Repair Surgery Unit, Department of Children's Surgery, Hospital R. del Río, between June and November, 1975, is reported. 27 cases of burned children were studied, including analysis of correlations of the stages and outcome of the disease (varicela), the trauma (burns) and the graft (repair surgery). As a result, the authors emphasize the following findings: 1. Burns and their repair are not aggravating factors for varicella. In a small number of cases the exanthema looked more confluent in the graft surgical areas and in the first degree burns healing spontaneously. 2. Usually there was an uneventful outcome of graft repair surgery on a varicella patient, either during the incubation period, the acme or the convalescence. 3. The fact that the outmost intensity of secondary viremia of varicella occurs before the onset of exanthemia, that is, during the late incubation period, is confirmed.

  6. Arteriovenous shunt graft ulceration with sinus and graft epithelialization

    Directory of Open Access Journals (Sweden)

    Pooja Singhal

    2015-03-01

    Full Text Available Arteriovenous fistula and grafts are used as access sites for patients with chronic kidney disease and are prone for complications. Stent grafts are used to treat access site complications. We report a rare and unusual finding of epithelialization of the sinus tract and the lumen of a polytetrafluoroethylene graft, following ulceration of the overlying skin.

  7. Reconsidering evidence-based practice in prosthetic rehabilitation : a shared enterprise

    NARCIS (Netherlands)

    van Twillert, S.; Geertzen, J.; Hemminga, T.; Postema, K.; Lettinga, A.

    Background: A divide is experienced between producers and users of evidence in prosthetic rehabilitation. Objective: To discuss the complexity inherent in establishing evidence-based practice in a prosthetic rehabilitation team illustrated by the case of prosthetic prescription for elderly

  8. Prosthetic limb sockets from plant-based composite materials.

    Science.gov (United States)

    Campbell, Andrew I; Sexton, Sandra; Schaschke, Carl J; Kinsman, Harry; McLaughlin, Brian; Boyle, Martin

    2012-06-01

    There is a considerable demand for lower limb prostheses globally due to vascular disease, war, conflict, land mines and natural disasters. Conventional composite materials used for prosthetic limb sockets include acrylic resins, glass and carbon fibres, which produce harmful gasses and dust in their manufacture. To investigate the feasibility of using a renewable plant oil-based polycarbonate-polyurethane copolymer resin and plant fibre composite, instead of conventional materials, to improve safety and accessibility of prosthetic limb manufacture. Experimental, bench research. Test pieces of the resin with a range of plant fibres (10.0% by volume) were prepared and tensile strengths were tested. Test sockets of both conventional composite materials and plant resin with plant fibres were constructed and tested to destruction. Combinations of plant resin and either banana or ramie fibres gave high tensile strengths. The conventional composite material socket and plant resin with ramie composite socket failed at a similar loading, exceeding the ISO 10328 standard. Both wall thickness and fibre-matrix adhesion played a significant role in socket strength. From this limited study we conclude that the plant resin and ramie fibre composite socket has the potential to replace the standard layup. Further mechanical and biocompatibility testing as well as a full economic analysis is required. Using readily sourced and renewable natural fibres and a low-volatile bio-resin has potential to reduce harm to those involved in the manufacture of artificial limb sockets, without compromising socket strength and benefitting clinicians working in poorer countries where safety equipment is scarce. Such composite materials will reduce environmental impact.

  9. Horizontal bone-augmentation procedures in implant dentistry: prosthetically guided regeneration.

    Science.gov (United States)

    Chiapasco, Matteo; Casentini, Paolo

    2018-02-25

    The rehabilitation of partially or totally edentulous patients with implant-supported prostheses has become routine, with excellent long-term outcome. A proper implant position is mandatory to achieve good functional and esthetic outcome and may require an adequate amount of alveolar bone and surrounding soft tissue. When this is lacking because of atrophy, sequelae of periodontal disease, traumas or congenital malformations, increased bone volume and/or keratinized mucosa can be obtained by guided bone regeneration, bone-grafting techniques and alveolar bone expansion. This article presents an evidence-based, prosthetically driven approach for the treatment of edentulous ridges with horizontal defects. The classification of bony defects, the main augmentation techniques, the selection criteria among different surgical procedures for different types of bony defects, and the advantages, disadvantages and limitations of each technique, are described in detail. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Confined relaxations of grafted polymer in solutions of linear polymer

    Science.gov (United States)

    Poling-Skutvik, Ryan; Krishnamoorti, Ramanan; Conrad, Jacinta

    Using neutron spin echo spectroscopy (NSE), we investigate the relaxations of polymer grafted to silica nanoparticles dispersed in semidilute solutions of linear polymer. The grafted polymer has a radius of gyration comparable to radius of the silica nanoparticle with a moderate grafting density so that the grafted polymer is more extended than a Gaussian chain. On length scales ranging from 1 to 20 nm and time scales less than 100 ns, the dynamics of the grafted polymer deviate from the standard Zimm model derived for linear polymers. Instead, the polymer chains are confined and unable to fully relax over the experimental time. The confinement length agrees with the distance between chains decreases as the linear polymer concentration is increased. Additionally, the confinement length is independent of linear polymer molecular weight, suggesting that linear polymer cannot penetrate the grafted layer. Instead, the grafted chains collapse onto themselves, similar to the structural changes observed in systems of star and linear polymers at high concentrations of linear polymer. We verify this physical picture using small-angle x-ray scattering and atomic force microscopy to observe aggregation of grafted particles at high concentrations of linear polymer.

  11. Graft Copolymerization Of Methyl Methacrylate Onto Agave Cellulose

    International Nuclear Information System (INIS)

    Noor Afizah Rosli; Ishak Ahmad; Ibrahim Abdullah; Farah Hannan Anuar

    2014-01-01

    The grafting polymerization of methyl methacrylate (MMA) and Agave cellulose was prepared and the grafting reaction conditions were optimized by varying the reaction time and temperature, and ratio of monomer to cellulose. The resulting graft copolymers were characterized by Fourier transform infrared, X-ray diffraction analysis, thermogravimetric analysis, and scanning electron microscopy (SEM). The experimental results showed that the optimal conditions were at a temperature of 45 degree Celsius for 90 min with ratio monomer to cellulose at 1:1 (g/ g). An additional peak at 1738 cm -1 which was attributed to the C=O of ester stretching vibration of poly(methyl methacrylate), appeared in the spectrum of grafted Agave cellulose. A slight decrease of crystallinity index upon grafting was found from 0.74 to 0.68 for cellulose and grafted cellulose, respectively. Grafting of MMA onto cellulose enhanced its thermal stability and SEM observation further furnished evidence of grafting MMA onto Agave cellulose with increasing cellulose diameter and surface roughness. (author)

  12. Graft nephrectomy: The SGPGI experience

    OpenAIRE

    Nand Kishore Arvind; Aneesh Srivastava; Anant Kumar; Subodh K Das

    2002-01-01

    Background: Graft nephrectomy is often considered a hazardous procedure with high morbidity and occasional mortality, and this may pose a technical challenge. The aim of this study was to evaluate the indications, etiology and complications following graft nephrectomy. Materials and Methods: From 1988 to 2001, among total of 1,019 live related renal transplants carried at our center, 46 underwent graft nephrectomy. Patients were divided into 2 groups depending on timing of graft re-mova...

  13. The noncovalent bonding of antibiotics to a polytetrafluoroethylene-benzalkonium graft

    International Nuclear Information System (INIS)

    Harvey, R.A.; Greco, R.S.

    1981-01-01

    This study evaluates the noncovalent bonding of anionic antibiotics to polytetrafluoroethylene grafts using benzalkonium chloride as a cationic anchor. The binding of radiolabeled surfactants and antibiotics was evaluated by liquid scintillation and in an in vitro microbiologic assay against Staphylococcus aureus. Significant quantities of antibiotic were bound when the grafts were pretreated with benzalkonium in ethanol or aqueous solution at elevated temperature. Bound antibiotic is stable in aqueous salt solutions, but slowly dissociates in the presence of blood or serum. The ionic nature of the bonding process is clarified by the use of a variety of antibiotics and surfactants with complementary charges. The ability of the benzalkonium treated grafts to adsorb antibiotic from blood is, likewise, demonstrated and the possibility of concomitantly binding heparin and antibiotic simultaneously is evaluated. These studies support the ability to noncovalently bond antibiotics to polytetrafluoroethylene surfaces and form the basis of eventually utilizing these surfaces in the prevention of vascular prosthetic infections

  14. The kinetics of normal and prosthetic wrists.

    Science.gov (United States)

    Tolbert, J R; Blair, W F; Andrews, J G; Crowninshield, R D

    1985-01-01

    The purposes of this study were (1) to describe normal wrist kinetics, and (2) to investigate the in-vitro kinetics of four currently available wrist prostheses (Swanson, Meuli, Volz, Hamas). The effective tendon moment arms of the six major wrist muscles were determined through the use of load cells and applied weights. Testing was conducted in a neutral wrist configuration with hand pronation-supination both constrained and unconstrained. The results indicate that each of the muscles studied has a unique set of effective tendon moment arms about the normal wrist as well as about wrists with the implanted prostheses, and that none of the prosthetic wrists studied duplicated normal wrist kinetics.

  15. Injectible bodily prosthetics employing methacrylic copolymer gels

    Energy Technology Data Exchange (ETDEWEB)

    Mallapragada, Surya K.; Anderson, Brian C.

    2007-02-27

    The present invention provides novel block copolymers as structural supplements for injectible bodily prosthetics employed in medical or cosmetic procedures. The invention also includes the use of such block copolymers as nucleus pulposus replacement materials for the treatment of degenerative disc disorders and spinal injuries. The copolymers are constructed by polymerization of a tertiary amine methacrylate with either a (poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) polymer, such as the commercially available Pluronic.RTM. polymers, or a poly(ethylene glycol) methyl ether polymer.

  16. Tactile sensing means for prosthetic limbs

    Science.gov (United States)

    Scott, W. L. (Inventor)

    1973-01-01

    An improved prosthetic device characterized by a frame and a socket for mounting on the stump of a truncated human appendage is described. Flexible digits extend from the distal end and transducers located within the digits act as sensing devices for detecting tactile stimuli. The transducers are connected through a power circuit with a slave unit supported by a strap and fixed to the stump. The tactile stimuli detected at the sensing devices are reproduced and applied to the skin of the appendage in order to stimulate the sensory organs located therein.

  17. Alveolar ridge sockets preservation with bone grafting--review.

    Science.gov (United States)

    Allegrini, Sergio; Koening, Bruno; Allegrini, Marcia Rivellino Facci; Yoshimoto, Marcelo; Gedrange, Tomasz; Fanghaenel, Jochen; Lipski, Mariusz

    2008-01-01

    Alveolar bone seems to play a key role in providing support to the teeth, which are anchored to the bone by desmodontal fibers. The progressive alveolar bone resorption process occurs due to a loss of anatomic, biologic and mechanical factors. Mechanical stimulation of alveolar bone during mastication is crucial in keeping the teeth and underlying bone healthy. Tooth extraction leads to typical bone deficiency of ridge width and height of alveolar crest and reduces the possibility of placing screw titanium implants. When tooth extraction is necessary, trauma should be minimized during the procedure and bone preservation should receive careful attention. The literature has shown that early bone loss can be significantly reduced by socket grafting. The process of socket grafting requires an understanding of wound healing and an appreciation of the biological properties of the products available for socket grafting. Augmentative measures may, thus, be required to guarantee optimal prosthetic replacement of the lost tissue. Success or failure of augmentation procedures is dependent on revascularization and remodelling of the grafted bone into a vital, load bearing bone. In contrast to a visible three-dimensional change, the concept of remodelling refers to the internal turnover of bone, which is a coupled process where osteoclastic resorption and osteoblastic formation are more or less balanced. To restore alveolar bone loss and support efficient placement of dental implants, many different bone substitute such as autografts, allografts, xenografts, synthetic biomaterials and osteoactive agents have been proposed. In order to avoid harvesting an autograft, and thereby eliminating additional surgical procedures and risks, bone grafting materials and substitutes are alternative filler materials to be used for ridge augmentation. To present a literature review about biomaterials applicable in alveolar ridge sockets preservation to future implants insertion. The

  18. Haemodynamics in axillobifemoral bypass grafts

    NARCIS (Netherlands)

    C.H. Wittens

    1992-01-01

    textabstractThis thesis is based on four publications on the subject of graft configuration and haemodynamics in axillobifemoral bypass grafts: 1. A clinical evaluation of 17 patients with axillobifemoral bypass graft operations, performed for various indications. Two important observations were

  19. Influences of irradiation on the anastomotic sites of artificial graft

    International Nuclear Information System (INIS)

    Ogawa, Junichi; Inoue, Hiroshi; Koide, Shirosaku; Kawada, Shimei; Shotsu, Akira

    1989-01-01

    To examine the acute influences of irradiation on the anastomotic sites of EPTFE vascular grafts, experimental study was performed using canine dogs. After replacement of superior vena cava and bilateral femoral arteries with EPTFE grafts, a total of 20 to 100 Gy doses were given at the anastomotic sites of superior vena cava and right femoral artery. There were no degradation of grafts themselves or rupture in the anastomoses at cumulative anastomotic sites of superior vena cava, stenoses and/or overgrowth of granulation tissues were observed, although at those of right femoral artery, no remarkable differences were observed between dogs which received irradiation and those which did not receive. (author)

  20. Indium-111-labeled leukocyte scan in detection of synthetic vascular graft infection: The effect of antibiotic treatment

    International Nuclear Information System (INIS)

    Chung, C.J.; Hicklin, O.A.; Payan, J.M.; Gordon, L.

    1991-01-01

    To determine the sensitivity and specificity of the indium-111-( 111 In) labeled leukocyte scan for prosthetic vascular graft infection in patients treated with antibiotic therapy, a retrospective study was performed. Of 41 consecutive 111 In-labeled leukocyte scans performed to evaluate possible vascular graft infection, 23 scans were performed in patients treated with antibiotics. The average duration of antibiotic therapy was 21 days. Twelve positive and 11 negative scans for graft infection were found. By surgical and autopsy correlation of all positive cases, and clinical correlation (of all negative cases), there were 10 true-positive, 11 true-negative, 2 false-positive, and no false-negative scans for graft infections, for an overall sensitivity of 100% and specificity of 85%

  1. Acrylonitrile grafted to PVDF

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jin; Eitouni, Hany Basam

    2015-03-31

    PVDF-g-PAN has been synthesized by grafting polyacrylonitrile onto polyvinylidene fluoride using an ATRP/AGET method. The novel polymer is ionically conducive and has much more flexibility than PVDF alone, making it especially useful either as a binder in battery cell electrodes or as a polymer electrolyte in a battery cell.

  2. Aortic Graft Infection Secondary to Iatrogenic Transcolonic Graft Malposition.

    Science.gov (United States)

    Blank, Jacqueline J; Rothstein, Abby E; Lee, Cheong Jun; Malinowski, Michael J; Lewis, Brian D; Ridolfi, Timothy J; Otterson, Mary F

    2018-01-01

    Aortic graft infections are a rare but devastating complication of aortic revascularization. Often infections occur due to contamination at the time of surgery. Iatrogenic misplacement of the limbs of an aortobifemoral graft is exceedingly rare, and principles of evaluation and treatment are not well defined. We report 2 cases of aortobifemoral bypass graft malposition through the colon. Case 1 is a 54-year-old male who underwent aortobifemoral bypass grafting for acute limb ischemia. He had previously undergone a partial sigmoid colectomy for diverticulitis. Approximately 6 months after vascular surgery, he presented with an occult graft infection. Preoperative imaging and intraoperative findings were consistent with graft placement through the sigmoid colon. Case 2 is a 60-year-old male who underwent aortobifemoral bypass grafting due to a nonhealing wound after toe amputation. His postoperative course was complicated by pneumonia, bacteremia thought to be secondary to the pneumonia, general malaise, and persistent fevers. Approximately 10 weeks after the vascular surgery, he presented with imaging and intraoperative findings of graft malposition through the cecum. Aortic graft infection is usually caused by surgical contamination and presents as an indolent infection. Case 1 presented as such; Case 2 presented more acutely. Both grafts were iatrogenically misplaced through the colon at the index operation. The patients underwent extra-anatomic bypass and graft explantation and subsequently recovered.

  3. Characterisation of the responsive properties of two running-specific prosthetic models.

    Science.gov (United States)

    Grobler, Lara; Ferreira, Suzanne; Vanwanseele, Benedicte; Terblanche, Elmarie E

    2017-04-01

    The need for information regarding running-specific prosthetic properties has previously been voiced. Such information is necessary to assist in athletes' prostheses selection. This study aimed to describe the characteristics of two commercially available running-specific prostheses. The running-specific prostheses were tested (in an experimental setup) without the external interference of athlete performance variations. Four stiffness categories of each running-specific prosthetic model (Xtend ™ and Xtreme ™ ) were tested at seven alignment setups and three drop masses (28, 38 and 48 kg). Results for peak ground reaction force (GRF peak ), contact time ( t c ), flight time ( t f ), reactive strength index (RSI) and maximal compression (Δ L) were determined during controlled dropping of running-specific prostheses onto a force platform with different masses attached to the experimental setup. No statistically significant differences were found between the different setups of the running-specific prostheses. Statistically significant differences were found between the two models for all outcome variables (GRF peak , Xtend > Xtreme; t c , Xtreme > Xtend; t f , Xtreme > Xtend; RSI, Xtend > Xtreme; Δ L, Xtreme > Xtend; p prosthetic choice. Physiologically and metabolically, a short sprint event (i.e. 100 m) places different demands on the athlete than a long sprint event (i.e. 400 m), and the RSP should match these performance demands.

  4. Stiffness and hysteresis properties of some prosthetic feet

    NARCIS (Netherlands)

    van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the

  5. Prosthetic Rehabilitation in Children: An Alternative Clinical Technique

    Directory of Open Access Journals (Sweden)

    Nádia Carolina Teixeira Marques

    2013-01-01

    Full Text Available Complete and partial removable dentures have been used successfully in numerous patients with oligodontia and/or anodontia. However, there is little information in the literature regarding the principles and guidelines to prosthetic rehabilitation for growing children. This case report describes the management of a young child with oligodontia as well as the treatment planning and the prosthetic rehabilitation technique.

  6. Prosthetic Rehabilitation in Children: An Alternative Clinical Technique

    Science.gov (United States)

    Teixeira Marques, Nádia Carolina; Gurgel, Carla Vecchione; Fernandes, Ana Paula; Lima, Marta Cunha; Machado, Maria Aparecida Andrade Moreira; Soares, Simone; Oliveira, Thais Marchini

    2013-01-01

    Complete and partial removable dentures have been used successfully in numerous patients with oligodontia and/or anodontia. However, there is little information in the literature regarding the principles and guidelines to prosthetic rehabilitation for growing children. This case report describes the management of a young child with oligodontia as well as the treatment planning and the prosthetic rehabilitation technique. PMID:24175103

  7. National Apprenticeship and Training Standards for Orthotic and Prosthetic Technicians.

    Science.gov (United States)

    American Orthotic and Prosthetic Association, Washington, DC.

    The booklet sets forth the National Apprenticeship and Training Standards for the one-year apprenticeship program for orthotic and/or prosthetic technicians, as developed and recommended by the American Orthotic and Prosthetic Association. Standards in various areas--such as qualifications for apprenticeship, hours of work, salaries, records,…

  8. Principles of obstacle avoidance with a transfemoral prosthetic limb

    NARCIS (Netherlands)

    van Keeken, Helco G.; Vrieling, Aline H.; Hof, At L.; Postema, Klaas; Otten, Bert

    2012-01-01

    In this study, conditions that enable a prosthetic knee flexion strategy in transfemoral amputee subjects during obstacle avoidance were investigated. This study explored the hip torque principle and the static ground principle as object avoidance strategies. A prosthetic limb simulator device was

  9. Prosthetic prescription in the Netherlands: An interview with clinical experts

    NARCIS (Netherlands)

    Van Der Linde, H.; Geertzen, J.H.B.; Hofstad, C.J.; Van Limbeek, Jacques; Postema, K.

    2004-01-01

    In the process of guideline development for prosthetic prescription in the Netherlands the authors made a study of the daily clinical practice of lower limb prosthetics. Besides the evidence-based knowledge from literature the more implicit knowledge from clinical experts is of importance for

  10. Maxillary sinus augmentation using sinus membrane elevation without grafts - A Systematic Review

    Directory of Open Access Journals (Sweden)

    Rakshith Hegde

    2016-01-01

    Full Text Available Implants have a predictable outcome and are the foremost treatment modality for prosthetic rehabilitation of edentulous patients. Due to loss of bone after extraction and pneumatization of maxillary sinus, there is insufficient bone volume for implant placement. The direct maxillary sinus lift procedure has been performed with different grafting materials (autogenous bone grafts, alloplasts, allografts, and xenografts and without grafting material, having new bone formation around the implant. There is no evidence to prove the need for grafting material in all direct sinus lift procedures, hence the need for this review. Previous meta-analysis showed that survival rates of implants placed in grafted maxillary sinuses had similar survival rates whether autogenous, allogenous, or alloplastic grafts were used. This paper aims to review scientific data on the direct sinus elevation technique without use of any grafting material, volume of new bone formed, and also mechanism behind this technique. Articles were searched from 1997 to October 2014 in PubMed, Google Scholar, and Cochrane CENTRAL. The study eligibility criteria were (1 direct sinus lift procedure without any graft material during implant placement and (2 human or animal studies with a minimum follow-up of 6 months or more. Two authors independently scrutinized the literature and if any controversy was raised, third author's opinion was sought to arrive at a mutual consensus for including the study in the review. Due to the heterogeneity across all studies in all study designs, the data were not pooled and a meta-analysis was not performed. Taking into consideration all factors reviewed in this regard along with the outcomes, the direct sinus lift technique without grafting can be suggested as a viable treatment option keeping in mind the limitations involved. The average bone gain was seen across all studies ranging from 2.37 to 10 mm and with an implant survival rate ranging from 79

  11. Sinus grafting and simultaneous removal of large antral pseudocysts of the maxillary sinus with a micro-invasive intraoral access.

    Science.gov (United States)

    Chiapasco, M; Palombo, D

    2015-12-01

    Large antral pseudocysts of the maxillary sinus (APCs) may hamper the elevation of the Schneiderian membrane during sinus grafting and may impair osteo-meatal complex patency after sinus augmentation. Therefore, these should be removed prior to or at the time of sinus grafting. This study presents a new technique that combines enucleation of large APCs during sinus grafting via a lateral approach with preservation of the Schneiderian membrane periosteal layer. Twelve patients underwent a sinus graft via lateral approach during the years 2004-2012. Simultaneous APC removal was achieved through a small additional bony access, preserving the integrity of the periosteal layer of the Schneiderian membrane. Nineteen implants were inserted at the time of sinus augmentation or during a second stage. Prosthetic rehabilitation was started at 4-6 months after implant placement. No patient developed surgical complications or APC recurrence. The survival rate of implants and related prostheses was 100% over a mean follow-up of 50 months (range 12-96 months) after completion of the prosthetic restorations. This technique may represent an effective procedure to achieve APC removal at the time of sinus grafting, preserving the integrity of the Schneiderian membrane periosteal layer. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  12. Is the Prosthetic Homologue Necessary for Embodiment?

    Science.gov (United States)

    Dornfeld, Chelsea; Swanston, Michelle; Cassella, Joseph; Beasley, Casey; Green, Jacob; Moshayev, Yonatan; Wininger, Michael

    2016-01-01

    Embodiment is the process by which patients with limb loss come to accept their peripheral device as a natural extension of self. However, there is little guidance as to how exacting the prosthesis must be in order for embodiment to take place: is it necessary for the prosthetic hand to look just like the absent hand? Here, we describe a protocol for testing whether an individual would select a hand that looks like their own from among a selection of five hands, and whether the hand selection (regardless of homology) is consistent across multiple exposures to the same (but reordered) set of candidate hands. Pilot results using healthy volunteers reveals that hand selection is only modestly consistent, and that selection of the prosthetic homologue is atypical (61 of 192 total exposures). Our protocol can be executed in minutes, and makes use of readily available equipment and softwares. We present both a face-to-face and a virtual protocol, for maximum flexibility of implementation. PMID:28066228

  13. The use of underactuation in prosthetic grasping

    Directory of Open Access Journals (Sweden)

    P. J. Kyberd

    2011-02-01

    Full Text Available Underactuation as a method of driving prosthetic hands has a long history. The pragmatic requirements of such a device to be light enough to be worn and used regularly have meant that any multi degree of freedom prosthetic hand must have fewer actuators than the usable degrees of freedom. Aesthetics ensures that while the hand needs five fingers, five actuators have considerable mass, and only in recent years has it even been possible to construct a practical anthropomorphic hand with five motors. Thus there is an important trade off as to which fingers are driven, and which joints on which fingers are actuated, and how the forces are distributed to create a functional device. This paper outlines some of the historical solutions created for this problem and includes those designs of recent years that are now beginning to be used in the commercial environment.

    This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010, 19 August 2010, Montréal, Canada.

  14. Is the prosthetic homologue necessary for embodiment?

    Directory of Open Access Journals (Sweden)

    Chelsea Dornfeld

    2016-12-01

    Full Text Available Embodiment is the process by which patients with limb loss come to accept their peripheral device as a natural extension of self. However, there is little guidance as to how exacting the prosthesis must be in order for embodiment to take place: is it necessary for the prosthetic hand to look just like the absent hand? Here, we describe a protocol for testing whether an individual would select a hand that looks like their own from among a selection of 5 hands, and whether the hand selection (regardless of homology is consistent across multiple exposures to the same (but reordered set of candidate hands. Pilot results using healthy volunteers reveals that hand selection is only modestly consistent, and that selection of the prosthetic homologue is atypical (61 of 192 total exposures. Our protocol can be executed in minutes, and makes use of readily available equipment and softwares. We present both a face-to-face and a virtual protocol, for maximum flexibility of implementation.

  15. Is the Prosthetic Homologue Necessary for Embodiment?

    Science.gov (United States)

    Dornfeld, Chelsea; Swanston, Michelle; Cassella, Joseph; Beasley, Casey; Green, Jacob; Moshayev, Yonatan; Wininger, Michael

    2016-01-01

    Embodiment is the process by which patients with limb loss come to accept their peripheral device as a natural extension of self. However, there is little guidance as to how exacting the prosthesis must be in order for embodiment to take place: is it necessary for the prosthetic hand to look just like the absent hand? Here, we describe a protocol for testing whether an individual would select a hand that looks like their own from among a selection of five hands, and whether the hand selection (regardless of homology) is consistent across multiple exposures to the same (but reordered) set of candidate hands. Pilot results using healthy volunteers reveals that hand selection is only modestly consistent, and that selection of the prosthetic homologue is atypical (61 of 192 total exposures). Our protocol can be executed in minutes, and makes use of readily available equipment and softwares. We present both a face-to-face and a virtual protocol, for maximum flexibility of implementation.

  16. Magnetic resonance imaging of prosthetic heart valves.

    Science.gov (United States)

    Soulen, R L; Budinger, T F; Higgins, C B

    1985-03-01

    To evaluate the safety of magnetic resonance (MR) imaging of prosthetic heart valves, nine different synthetic and tissue valves were studied ex vivo. Deflection was measured in 0.35-tesla (T) and 1.5-T superconducting magnets and at the edge of the bore of a 2.35-T electromagnet in field gradients of 5, 1.1, and 6.3 mT/cm, respectively. No valve deflected in the 0.35-T magnet; six synthetic valves deflected 0.25 degrees-3 degrees in the 1.5-T magnet; all valves deflected 1 degree-27 degrees at the edge of the 2.35-T magnet. Each valve was then submerged in a vial of water and the temperature was measured immediately before and after each of two spin-echo imaging sequences in the two superconducting magnets. No significant temperature rise followed exposure in either magnet. Image distortion varied from negligible to severe in both imagers; magnitude of distortion paralleled magnitude of deflection. These data suggest that patients with present-day prosthetic heart valves can be safely imaged in present-day MR imagers and that prosthesis-induced artifacts will not interfere with interpretation in most instances.

  17. The Prosthetic Workflow in the Digital Era

    Directory of Open Access Journals (Sweden)

    Lidia Tordiglione

    2016-01-01

    Full Text Available The purpose of this retrospective study was to clinically evaluate the benefits of adopting a full digital workflow for the implementation of fixed prosthetic restorations on natural teeth. To evaluate the effectiveness of these protocols, treatment plans were drawn up for 15 patients requiring rehabilitation of one or more natural teeth. All the dental impressions were taken using a Planmeca PlanScan® (Planmeca OY, Helsinki, Finland intraoral scanner, which provided digital casts on which the restorations were digitally designed using Exocad® (Exocad GmbH, Germany, 2010 software and fabricated by CAM processing on 5-axis milling machines. A total of 28 single crowns were made from monolithic zirconia, 12 vestibular veneers from lithium disilicate, and 4 three-quarter vestibular veneers with palatal extension. While the restorations were applied, the authors could clinically appreciate the excellent match between the digitally produced prosthetic design and the cemented prostheses, which never required any occlusal or proximal adjustment. Out of all the restorations applied, only one exhibited premature failure and was replaced with no other complications or need for further scanning. From the clinical experience gained using a full digital workflow, the authors can confirm that these work processes enable the fabrication of clinically reliable restorations, with all the benefits that digital methods bring to the dentist, the dental laboratory, and the patient.

  18. Improvement of grafting procedures for the ornamental species: II. Abies concolor [(Gord. & Glend. Lindl

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2012-06-01

    Full Text Available The achieved results concerning the grafting silver-fir - Abies concolor [(Gord. & Glend. Lindl] scions on white-fir (Abies alba Mill. rootstocks are reporting in this article. The double-side-veneer grafting method and the plastic tape and the ecological CeraltinŽ wax were applied in four experimental variants. The side-veneer-grafting method and the classic materials, such as raffia and the hot wax were used at the two controls involved in this experiment. The grafting success expressed in percents, were transformed in arcsin square root of percent values, and a two-way analysis of variance was performed. Highly significant (p < 0.001 statistical differences were found between grafting variants, including controls. The Duncan Multiple Range Test showed that the four experimental grafting variants were highly significantly (p < 0.01 be-tter than the two controls. The grafting success of the best experimental variant has surpassed the two controls by 129 and 153%, respectively. Consequently, the double-side-veneer grafting method, the new developed plastic tape and the ecological CeraltinŽ wax have contributed to this grafting success owing to which they are recommended to be used for grafting silver-fir ornamental trees.

  19. Improvement of grafting procedures for the ornamental species: II. Abies concolor [(Gord. & Glend. Lindl

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2012-05-01

    Full Text Available The achieved results concerning the grafting silver-fir - Abiesconcolor [(Gord. & Glend. Lindl] scions on white-fir (Abies alba Mill.rootstocks are reporting in this article. The double-side-veneer grafting method and the plastic tape and the ecological Ceraltin® wax were applied in four experimental variants. The side-veneer-grafting method and the classic materials, such as raffia and the hot wax were used at the two controls involved in this experiment. The grafting success expressed in percents, were transformed in arcsin square root of percent values, and a two-way analysis of variance was performed. Highly significant (p <0.001 statistical differences were found between grafting variants, including controls. The Duncan Multiple Range Test showed that the four experimental grafting variants were highly significantly (p < 0.01 better than the two controls. The grafting success of the best experimental variant has surpassed the two controls by 129 and 153%, respectively.Consequently, the double-side-veneer grafting method, the new developed plastic tape and the ecological Ceraltin® wax have contributed to this grafting success owing to which they are recommended to be used for grafting silver-fir ornamental trees.

  20. Systemic thioridazine in combination with dicloxacillin against early aortic graft infections caused by Staphylococcus aureus in a porcine model

    DEFF Research Database (Denmark)

    Stenger, Michael; Behr-Rasmussen, Carsten; Klein, Kasper

    2017-01-01

    INTRODUCTION: Conservative treatment solutions against aortic prosthetic vascular graft infection (APVGI) for inoperable patients are limited. The combination of antibiotics with antibacterial helper compounds, such as the neuroleptic drug thioridazine (TDZ), should be explored. AIM: To investiga...... results against APVGI caused by MSSA in this porcine model. However, unexpected severe adverse effects related to the planned dose of TDZ required a considerable reduction to the administered dose of TDZ, which may have compromised the results....

  1. A Powered Prosthetic Intervention for Bilateral Transfemoral Amputees

    Science.gov (United States)

    Lawson, Brian E.; Ruhe, Brian; Shultz, Amanda; Goldfarb, Michael

    2014-01-01

    This paper presents the design and validation of a control system for a pair of powered knee and ankle prostheses to be used as a prosthetic intervention for bilateral transfemoral amputees. The control system leverages communication between the prostheses for enhanced awareness and stability, along with power generation at the knee and ankle joints to better restore biomechanical functionality in level ground walking. The control methodology employed is a combination of an impedance-based framework for weight-bearing portions of gait and a trajectory-based approach for the non-weight-bearing portions. The control system was implemented on a pair of self-contained powered knee and ankle prostheses, and the ability of the prostheses and control approach to provide walking functionality was assessed in a set of experimental trials with a bilateral transfemoral amputee subject. Specifically, experimental data from these trials indicate that the powered prostheses and bilateral control architecture provide gait kinematics that reproduce healthy gait kinematics to a greater extent than the subject’s daily-use passive prostheses. PMID:25014950

  2. Hydrogen, a potential safeguard for graft-versus-host disease and graft ischemia-reperfusion injury?

    Science.gov (United States)

    Yuan, Lijuan; Shen, Jianliang

    2016-01-01

    Post-transplant complications such as graft-versus-host disease and graft ischemia-reperfusion injury are crucial challenges in transplantation. Hydrogen can act as a potential antioxidant, playing a preventive role against post-transplant complications in animal models of multiple organ transplantation. Herein, the authors review the current literature regarding the effects of hydrogen on graft ischemia-reperfusion injury and graft-versus-host disease. Existing data on the effects of hydrogen on ischemia-reperfusion injury related to organ transplantation are specifically reviewed and coupled with further suggestions for future work. The reviewed studies showed that hydrogen (inhaled or dissolved in saline) improved the outcomes of organ transplantation by decreasing oxidative stress and inflammation at both the transplanted organ and the systemic levels. In conclusion, a substantial body of experimental evidence suggests that hydrogen can significantly alleviate transplantation-related ischemia-reperfusion injury and have a therapeutic effect on graft-versus-host disease, mainly via inhibition of inflammatory cytokine secretion and reduction of oxidative stress through several underlying mechanisms. Further animal experiments and preliminary human clinical trials will lay the foundation for hydrogen use as a drug in the clinic. PMID:27652837

  3. Study of the grafting of dyes for the design of a pH optode

    Science.gov (United States)

    Fages, Mathias; Doizi, Denis; Deniau, Guy

    2015-05-01

    So as to covalently graft a chemical on a substrate, the GraftFastTM process can be used; the only requirement is that the chemical has at least one aromatic primary amine. In this work, this simple and fast process is presently used to graft dyes that are pH sensitive on an optical fiber, thus creating a pH sensor called optode. The major asset of this grafting process is that the dye is covalently grafted on the fiber, resolving stability issues encountered with other techniques - like physical entrapment or electrostatic interactions. Two different dyes have been successfully grafted on gold lamellas (which are the reference substrates for the GraftFastTM process), and an innovative experimental method to increase the thickness of the dye layer has been developed.

  4. Prosthetic finger phalanges with lifelike skin compliance for low-force social touching interactions

    Directory of Open Access Journals (Sweden)

    Ge Shuzhi

    2011-03-01

    Full Text Available Abstract Background Prosthetic arms and hands that can be controlled by the user's electromyography (EMG signals are emerging. Eventually, these advanced prosthetic devices will be expected to touch and be touched by other people. As realistic as they may look, the currently available prosthetic hands have physical properties that are still far from the characteristics of human skins because they are much stiffer. In this paper, different configurations of synthetic finger phalanges have been investigated for their skin compliance behaviour and have been compared with the phalanges of the human fingers and a phalanx from a commercially available prosthetic hand. Methods Handshake tests were performed to identify which areas on the human hand experience high contact forces. After these areas were determined, experiments were done on selected areas using an indenting probe to obtain the force-displacement curves. Finite element simulations were used to compare the force-displacement results of the synthetic finger phalanx designs with that of the experimental results from the human and prosthetic finger phalanges. The simulation models were used to investigate the effects of (a varying the internal topology of the finger phalanx and (b varying different materials for the internal and external layers. Results and Conclusions During handshake, the high magnitudes of contact forces were observed at the areas where the full grasping enclosure of the other person's hand can be achieved. From these areas, the middle phalanges of the (a little, (b ring, and (c middle fingers were selected. The indentation experiments on these areas showed that a 2 N force corresponds to skin tissue displacements of more than 2 mm. The results from the simulation model show that introducing an open pocket with 2 mm height on the internal structure of synthetic finger phalanges increased the skin compliance of the silicone material to 235% and the polyurethane material to

  5. Periorbital fat grafting.

    Science.gov (United States)

    Massry, Guy G; Azizzadeh, Babak

    2013-02-01

    Periorbital aging is a multifactorial process involving volume loss (bone and soft tissue), tissue decent, and cutaneous degenerative changes. Traditional approaches to surgery on this area of the face have been subtractive in nature, focusing on excision of skin, muscle, and fat. This has frequently led to a gaunt or hollowed postoperative appearance. Contemporary aesthetic eyelid and periorbital rejuvenation has undergone a paradigm shift from an excisionally based surgical approach to one that prioritizes volume preservation and/or augmentation. The development of fat grafting to the eyelids and periorbita has given the eyelid surgeon a viable surgical alternative to prevent postoperative volume depletion, maintain the smooth transition of the lower eyelid to the cheek, and aid in restoring the youthful appearance desired after surgery. This article will focus of periorbital fat grafting and touch upon fat preservation techniques as primary restorative procedures or as surgical adjuncts. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  6. Grafted polymer chains suppress nanoparticle diffusion in athermal polymer melts

    Science.gov (United States)

    Lin, Chia-Chun; Griffin, Philip J.; Chao, Huikuan; Hore, Michael J. A.; Ohno, Kohji; Clarke, Nigel; Riggleman, Robert A.; Winey, Karen I.; Composto, Russell J.

    2017-05-01

    We measure the center-of-mass diffusion of poly(methyl methacrylate) (PMMA)-grafted nanoparticles (NPs) in unentangled to slightly entangled PMMA melts using Rutherford backscattering spectrometry. These grafted NPs diffuse ˜100 times slower than predicted by the Stokes-Einstein relation assuming a viscosity equal to bulk PMMA and a hydrodynamic NP size equal to the NP core diameter, 2Rcore = 4.3 nm. This slow NP diffusion is consistent with an increased effective NP size, 2Reff ≈ 20 nm, nominally independent of the range of grafting density and matrix molecular weights explored in this study. Comparing these experimental results to a modified Daoud-Cotton scaling estimate for the brush thickness as well as dynamic mean field simulations of polymer-grafted NPs in athermal polymer melts, we find that 2Reff is in quantitative agreement with the size of the NP core plus the extended grafted chains. Our results suggest that grafted polymer chains of moderate molecular weight and grafting density may alter the NP diffusion mechanism in polymer melts, primarily by increasing the NP effective size.

  7. Pre-prosthetic and prosthetic treatment of patients with injuries and orofacial anomalies: A case report

    OpenAIRE

    Ajduković, Zorica R.; Krasić, Dragan Đ.; Filipović, Gordana Lj.; Kenić-Marinković, Dragana M.; Petrović, Nenad D.; Đorđević, Nadica S.

    2013-01-01

    Introduction Dentistry is the science that deals with the prevention, recognition and elimination of pathological changes in the orofacial system. Injuries in the orofacial region have become more frequent in recent years, and if these injuries are not properly treated, they may lead to permanent deformity and inability for adequate stomatoprosthetic treatment. Case Report This paper presents a surgical-prosthetic treatment and rehabilitation of a 49-year-old patient with traumatic injuries o...

  8. Vein grafting in fingertip replantations.

    Science.gov (United States)

    Yan, Hede; Jackson, William D; Songcharoen, Somjade; Akdemir, Ovunc; Li, Zhijie; Chen, Xinglong; Jiang, Liangfu; Gao, Weiyang

    2009-01-01

    In this retrospective study, the survival rates of fingertip replantation with and without vein grafting were evaluated along with their postoperative functional and cosmetic results. One hundred twenty-one-fingertip amputations were performed in 103 patients between September 2002 and July 2007. Thirty-four amputated fingertips were replanted without vein grafting, while 87 amputated fingertips were replanted with vein grafting for arterial and/or venous repairs. The overall survival rates of the replantations with and without vein grafting were 90% (78/87) and 85% (29/34), respectively. The survival rates were 88% (36/41) with venous repair, 93% (25/27) with arterial repair, and 89% (17/19) with both. Nineteen patients without vein grafting and 48 patients with vein grafting had a follow-up period of more than one year. Good cosmetic and functional outcomes were observed in both groups of patients. The results show that vein grafting is a reliable technique in fingertip replantations, showing no significant difference (P > 0.05) in survival between those with and without vein grafting. Furthermore, no significant difference (P > 0.05) in survival was found between cases with vein grafts for arterial and/or venous repairs. In fingertip replantations with vein grafting, favorable functional and esthetic results can be achieved without sacrificing replantation survival. (c) 2009 Wiley-Liss, Inc.

  9. Passive prosthetic hands and tools: A literature review.

    Science.gov (United States)

    Maat, Bartjan; Smit, Gerwin; Plettenburg, Dick; Breedveld, Paul

    2018-02-01

    The group of passive prostheses consists of prosthetic hands and prosthetic tools. These can either be static or adjustable. Limited research and development on passive prostheses has been performed although many people use these prosthesis types. Although some publications describe passive prostheses, no recent review of the peer-reviewed literature on passive prostheses is available. Review the peer-reviewed literature on passive prostheses for replacement of the hand. Literature review. Four electronic databases were searched using a Boolean combination of relevant keywords. English-language articles relevant to the objective were selected. In all, 38 papers were included in the review. Publications on passive prosthetic hands describe their users, usage, functionality, and problems in activities of daily living. Publications on prosthetic tools mostly focus on sport, recreation, and vehicle driving. Passive hand prostheses receive little attention in prosthetic research and literature. Yet one out of three people with a limb deficiency uses this type of prosthesis. Literature indicates that passive prostheses can be improved on pulling and grasping functions. In the literature, ambiguous names are used for different types of passive prostheses. This causes confusion. We present a new and clear classification of passive prostheses. Clinical relevance This review provides information on the users of passive prosthetic hands and tools, their usage and the functionality. Passive prostheses receive very little attention and low appreciation in literature. Passive prosthetic hands and tools show to be useful to many unilateral amputees and should receive more attention and higher acceptance.

  10. Predicting prosthetic prescription after major lower-limb amputation.

    Science.gov (United States)

    Resnik, Linda; Borgia, Matthew

    2015-01-01

    We describe prosthetic limb prescription in the first year following lower-limb amputation and examine the relationship between amputation level, geographic region, and prosthetic prescription. We analyzed 2005 to 2010 Department of Veterans Affairs (VA) Inpatient and Medical Encounters SAS data sets, Vital Status death data, and National Prosthetic Patient Database data for 9,994 Veterans who underwent lower-limb amputation at a VA hospital. Descriptive statistics and bivariates were examined. Cox proportional hazard models identified factors associated with prosthetic prescription. Analyses showed that amputation level was associated with prosthetic prescription. The hazard ratios (HRs) were 1.41 for ankle amputation and 0.46 for transfemoral amputation compared with transtibial amputation. HRs for geographic region were Northeast = 1.49, Upper Midwest = 1.26, and West = 1.39 compared with the South (p prosthetic prescription. Being married was positively associated. After adjusting for patient characteristics, people with ankle amputation were most likely to be prescribed a prosthesis and people with transfemoral amputation were least likely. Geographic variation in prosthetic prescription exists in the VA and further research is needed to explain why.

  11. Sensory feedback in upper limb prosthetics.

    Science.gov (United States)

    Antfolk, Christian; D'Alonzo, Marco; Rosén, Birgitta; Lundborg, Göran; Sebelius, Fredrik; Cipriani, Christian

    2013-01-01

    One of the challenges facing prosthetic designers and engineers is to restore the missing sensory function inherit to hand amputation. Several different techniques can be employed to provide amputees with sensory feedback: sensory substitution methods where the recorded stimulus is not only transferred to the amputee, but also translated to a different modality (modality-matched feedback), which transfers the stimulus without translation and direct neural stimulation, which interacts directly with peripheral afferent nerves. This paper presents an overview of the principal works and devices employed to provide upper limb amputees with sensory feedback. The focus is on sensory substitution and modality matched feedback; the principal features, advantages and disadvantages of the different methods are presented.

  12. 78 FR 69176 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

    Science.gov (United States)

    2013-11-18

    ... AFFAIRS Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting The..., that a meeting of the Federal Advisory Committee on Prosthetics and Special-Disabilities Programs will... Veterans Affairs on VA's prosthetics programs designed to provide state-of-the- art prosthetics and the...

  13. 77 FR 65609 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

    Science.gov (United States)

    2012-10-29

    ... AFFAIRS Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting The..., that a meeting of the Federal Advisory Committee on Prosthetics and Special-Disabilities Programs will... Veterans Affairs on VA's prosthetics programs designed to provide state-of-the- art prosthetics and the...

  14. 78 FR 48941 - Advisory Committee on Prosthetics and Special-Disabilities Programs, Notice of Meeting

    Science.gov (United States)

    2013-08-12

    ... AFFAIRS Advisory Committee on Prosthetics and Special-Disabilities Programs, Notice of Meeting The..., that a meeting of the Federal Advisory Committee on Prosthetics and Special-Disabilities Programs will... Veterans Affairs on VA's prosthetics programs designed to provide state-of-the- art prosthetics and the...

  15. 75 FR 24775 - Advisory Committee on Prosthetics and Special Disabilities Programs; Notice of Meeting

    Science.gov (United States)

    2010-05-05

    ... AFFAIRS Advisory Committee on Prosthetics and Special Disabilities Programs; Notice of Meeting The...) that a meeting of the Advisory Committee on Prosthetics and Special Disabilities Programs (the... Secretary of Veterans Affairs on VA's prosthetic programs designed to provide state-of-the- art prosthetics...

  16. 76 FR 21107 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

    Science.gov (United States)

    2011-04-14

    ... AFFAIRS Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting The...) that a meeting of the Advisory Committee on Prosthetics and Special-Disabilities Programs will be held... Veterans Affairs on VA's prosthetics programs designed to provide state-of-the art prosthetics and the...

  17. A mechanism to compensate undesired stiffness in joints of prosthetic hands.

    Science.gov (United States)

    Smit, Gerwin; Plettenburg, Dick; Van der Helm, Frans

    2014-04-01

    Cosmetic gloves that cover a prosthetic hand have a parasitic positive stiffness that counteracts the flexion of a finger joint. Reducing the required input torque to move a finger of a prosthetic hand by compensating the parasitic stiffness of the cosmetic glove. Experimental, test bench. The parasitic positive stiffness and the required input torques of a polyvinyl chloride glove and a silicone glove were measured when flexing a metacarpophalangeal finger joint for 90°. To compensate this positive stiffness, an adjustable compensation mechanism with a negative stiffness was designed and built. A MATLAB model was created to predict the optimal settings of the mechanism, based on the measured stiffness, in order to minimize the required input torque of the total system. The mechanism was tested in its optimal setting with an applied glove. The mechanism reduced the required input torque by 58% for the polyvinyl chloride glove and by 52% for the silicone glove. The total energy dissipation of the joint did not change significantly. This study shows that the undesired positive stiffness in the joint can be compensated with a relatively simple negative stiffness mechanism, which fits inside a finger of a standard cosmetic glove. Clinical relevance This study presents a mechanism that compensates the undesired stiffness of cosmetic gloves on prosthetic hands. As a result, it requires less input force, torque and energy to move the fingers. Application of this mechanism in body-powered hands will reduce the control effort of the user.

  18. Analysis and Evaluation of the Dynamic Performance of SMA Actuators for Prosthetic Hand Design

    Science.gov (United States)

    O'Toole, Kevin T.; McGrath, Mark M.; Coyle, Eugene

    2009-08-01

    It is widely acknowledged within the biomedical engineering community that shape memory alloys (SMAs) exhibit great potential for application in the actuation of upper limb prosthesis designs. These lightweight actuators are particularly suitable for prosthetic hand solutions. A four-fingered, 12 degree-of-freedom prosthetic hand has been developed featuring SMA bundle actuators embedded within the palmar structure. Joule heating of the SMA bundle actuators generates sufficient torque at the fingers to allow a wide range of everyday tasks to be carried out. Transient characterization of SMA bundles has shown that performance/response during heating and cooling differs substantially. Natural convection is insufficient to provide for adequate cooling during elongation of the actuators. An experimental test-bed has been developed to facilitate analysis of the heat transfer characteristics of the appropriately sized SMA bundle actuators for use within the prosthetic hand design. Various modes of heat sinking are evaluated so that the most effective wire-cooling solution can be ascertained. SMA bundles of varying size will be used so that a generalized model of the SMA displacement performance under natural and forced cooling conditions can be obtained. The optimum cooling solution will be implemented onto the mechanical hand framework in future work. These results, coupled with phenomenological models of SMA behavior, will be used in the development of an effective control strategy for this application in future work.

  19. Using skeletonised grafts for coronary artery bypass grafting.

    Science.gov (United States)

    Bawany, Faizan Imran; Khan, Muhammad Shahzeb; Khan, Asadullah; Kazi, Abdul Nafey; Naeem, Muhammed

    2014-05-01

    Coronary artery bypass graft surgery relieves angina symptoms and reduces mortality among ischaemic heart disease patients. It remains the gold standard for the treatment of multi-vessel and left main coronary artery disease. It is a well-known fact that internal mammary artery conduits have excellent and long-lasting patency when used for coronary artery bypass grafting. Its supremacy is largely because it prevents atherosclerosis. The old-style internal mammary artery bypass grafting, classically known as pedicle grafting, includes a circular rim of tissue around the graft. Bilateral pedicled internal mammary arteries, especially among diabetic patients, have been reported to cause complications in the sternum like sternal osteomyelitis. In many studies it has been reported that dissection of pedicled internal mammary artery can lead to sternal devascularisation which can lead to higher incidence of infections. Considering the higher incidence of deep sternal infections in patients with double pedicled arterial grafts, dissection of internal mammary artery in skeletonised manner was proposed. In this review, we outline the advantages of skeletonised grafting with respect to incidence of sternal infection, patency rates, blood flow, post-coronary artery bypass graft pain and the length of the graft.

  20. Genitourinary Prosthetics: A Primer for the Non-urologic Surgeon.

    Science.gov (United States)

    Lavien, Garjae; Zaid, Uwais; Peterson, Andrew C

    2016-06-01

    Genitourinary prosthetics are used for correction of functional deficits and to improve the quality of lives of affected patients. General surgeons must evaluate patients scheduled for nonurologic surgery with urologic devices that can impact their perioperative management. Lack of recognition of these prosthetics preoperatively can lead to unnecessary morbidity for the patient and have legal implications for the surgeon. Close consultation with a urologist may avoid common complications associated with these devices and allows for surgical assistance when operative misadventures do occur. This article reviews 3 common urologic prosthetics: testicular prosthesis, artificial urinary sphincter, and penile prosthesis. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Prosthetic options available for the diabetic lower limb amputee.

    Science.gov (United States)

    Chitragari, Gautham; Mahler, David B; Sumpio, Brandon J; Blume, Peter A; Sumpio, Bauer E

    2014-01-01

    Although the rate of lower limb amputation in patients with diabetes is decreasing, amputation still remains a major complication of diabetes. Prosthetics have been long used to help amputees ambulate. The last decade has seen many advances in prostheses with the enhanced understanding of the mechanics of ambulation and improved use of technology. This review describes the different types of prosthetic options available for below knee, ankle, and foot amputees, emphasizing the latest advances in prosthetic design. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Gait analysis in lower-limb amputation and prosthetic rehabilitation.

    Science.gov (United States)

    Esquenazi, Alberto

    2014-02-01

    Gait analysis combined with sound clinical judgment plays an important role in elucidating the factors involved in the pathologic prosthetic gait and the selection and effects of available interventions to optimize it. Detailed clinical evaluation of walking contributes to the analysis of the prosthetic gait, but evaluation in the gait laboratory using kinetic and kinematic data is often necessary to quantify and identify the particular contributions of the variables impacting the gait with confidence and assess the results of such intervention. The same approach can be considered when selecting prosthetic components and assessing leg length in this patient population. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Thrombolytic therapy in prosthetic valve thrombosis during early pregnancy

    Directory of Open Access Journals (Sweden)

    B.C. Srinivas

    2012-01-01

    Full Text Available Regardless of the improvements in the design of prosthetic heart valves and the use of anticoagulation, systemic embolism and valve thrombosis remains the most dreaded complications of mechanical heart valve replacement. A course of thrombolytic therapy may be considered as a first-line therapy for prosthetic heart valve thrombosis. The safety of thrombolysis in early pregnancy is not known. We describe a primigravida with mitral valve replacement status presenting with acute prosthetic valve thrombosis and treated successfully with intravenous streptokinase.

  4. Mechanical testing of pericardium for manufacturing prosthetic heart valves.

    Science.gov (United States)

    Aguiari, Paola; Fiorese, Michele; Iop, Laura; Gerosa, Gino; Bagno, Andrea

    2016-01-01

    Mammalian pericardia are currently used for the production of percutaneous prosthetic heart valves. The characteristics of biological tissues largely influence the durability of prosthetic devices used in the percutaneous approach and in traditional surgery, too. This paper reviews methodologies employed to assess and compare mechanical properties of pericardial patches from different mammalian species in order to identify the biomaterials adequate for manufacturing prosthetic heart valves. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  5. Prosthetic status and prosthetic need among the patients attending various dental institutes of ahmedabad and gandhinagar district, gujarat.

    Science.gov (United States)

    Shah, Vrinda R; Shah, Darshana N; Parmar, Chaitanya H

    2012-09-01

    The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment form (1997). Prosthetic status and prosthetic treatment need was recorded. Out of 510, any type of Edentulousness was 322 (63 %). Among them, 254 (49.8 %) were partially edentulous while 68 (13.3 %) were completely edentulous. Only 69 (13 %) were having any prosthesis in upper arch while only 80 (16 %) were having any prosthesis in lower arch. Need for any type of prosthesis in upper and lower arch was 55 and 60 % in males and females, respectively. In lower social class group need of prosthesis in upper and lower arch was 62 and 63 %, respectively. It was found that prosthetic status and prosthetic treatment need increased with increase in age. Steps should be taken to overcome this disparity and more emphasis should be given to meet the felt need of the people through government and non government organizations to improve the oral health. The unmet prosthetic treatment need should be met to rehabilitate needy people so that their disability may be limited.

  6. Long-term quality of life and mobility after prosthetic above-the-knee bypass surgery.

    Science.gov (United States)

    Bosma, Jan; Turkçan, Kagan; Assink, Joeri; Wisselink, Willem; Vahl, Anco C

    2012-02-01

    Multiple studies have addressed above-the-knee femoral artery bypass grafting; however, information on late quality of life (QoL) and mobility is scarce. We studied long-term QoL and mobility after above-the-knee bypass surgery. Consecutive patients presenting with claudication, ischemic rest pain, or gangrene who received above-the-knee prosthetic bypass grafting between December 1997 and January 2003 were included in this observational study. Data used were recorded in a prospectively collected database of patients receiving Dacron and polytetrafluoroethylene (PTFE) supragenicular bypasses for lower limb ischemia. Primary outcomes were QoL and mobility, and secondary outcomes were patency and patient survival. QoL was measured with the EuroQol questionnaire (EQ-5D/EQ-VAS). Mobility was assessed with the Walking Impairment Questionnaire (WIQ) and analyzed in univariate and multivariate models. Patency and survival were computed with Cox regression. One hundred forty patients were treated during the study period. Sixty-nine patients (50%) died during follow-up, leaving 71 survivors who were asked (63 [89%] complied) to complete the EQ-5D/EQ-VAS and WIQ questionnaires. None of the primary outcome parameters (WIQ, EQ-5D, EQ-VAS) were affected by primary bypass occlusion (p = 0.34, p = 0.44, and p = 0.27, respectively) or long-term patency (p = 0.07, p = 0.54, and p = 0.36, respectively). Male sex was significantly associated with a better outcome on all primary outcome parameters. Patients with Dacron versus PTFE grafts had WIQ scores of 0.49 and 0.26, respectively (p = 0.01). EQ-5D scores of patients with Dacron and PTFE were 0.576 and 0.409 (p = 0.08) and EQ-VAS scores were 61 and 54, respectively (p = 0.24). Graft type was not independently associated with occlusion, but runoff was. The 5-year and 10-year patient survival rates were 58% and 51%, respectively. In this study, long-term QoL and mobility did not seem to be associated with bypass patency, as assessed

  7. The Effect of Platelet-Rich Plasma on Survival of the Composite Graft and the Proper Time of Injection in a Rabbit Ear Composite Graft Model

    Directory of Open Access Journals (Sweden)

    Hyun Nam Choi

    2014-11-01

    Full Text Available BackgroundAdministration of growth factors has been associated with increased viability of composite grafts greater than 1-cm in diameter. Platelet-rich plasma (PRP contains many of the growth factors studied. In this study, we evaluate the effect of PRP injection on composite graft viability and the proper time for injection.MethodsA total of 24 New Zealand White rabbits were divided into four groups. Autologous PRP was injected into the recipient sites three days before grafting in group 1, on the day of grafting in group 2, and three days after grafting in group 3. Group 4 served as control without PRP administration. Auricular composite grafts of 3-cm diameter were harvested and grafted back into place after being rotated 180 degrees. Median graft viability and microvessel density were evaluated at day 21 of graft via macroscopic photographs and immunofluorescent staining, respectively.ResultsThe median graft survival rate was 97.8% in group 1, 69.2% in group 2, 55.7% in group 3, and 40.8% in the control group. The median vessel counts were 34 (per ×200 HPF in group 1, 24.5 in group 2, 19.5 in group 3, and 10.5 in the control group.ConclusionsThis study demonstrates that PRP administration is associated with increased composite graft viability. All experimental groups showed a significantly higher survival rate and microvessel density, compared with the control group. Pre-administration of PRP was followed by the highest graft survival rate and revascularization. PRP treatments are minimally invasive, fast, easily applicable, and inexpensive, and offer a potential clinical pathway to larger composite grafts.

  8. Micrografts: the "super" expansion graft.

    Science.gov (United States)

    Mardovin, W; Miller, S F; Eppinger, M; Finley, R K

    1992-01-01

    A novel technique for producing micronized skin grafts that was introduced in a paper presented at the 1990 ABA meeting was evaluated to quantify maximum expansion. Twenty Sprague-Dawley rats were divided into two groups representing 10:1 and 25:1 expanded micrograft ratios, respectively. Grafted sites in both groups were shown to heal better than those of the control group, and both grafted groups showed comparable healing at day 10.

  9. Environmental application of radiation grafting

    International Nuclear Information System (INIS)

    Tamada, Masao

    2007-01-01

    Adsorbent having high selectivity against a certain metal ion was synthesized by means of radiation-induced graft polymerization for the purpose of environmental application. The resulting adsorbents were utilized for the removal of toxic metal from scallop waste and the collection of uranium from seawater. As a novel application of grafting, the biodegradability of poly-hydroxybutylate was controlled by grafting. The biodegradability could be depressed by the graft chain and then recovered by external stimuli such as thermal and chemical treatments. (author)

  10. Development of electron beam grafted co-polymer membranes for recovery of uranium from seawater: process parameter standardization

    International Nuclear Information System (INIS)

    Bhardwaj, Y.K.; Virendra Kumar; Sarma, K.S.S.; Khader, S.A.; Sabharwal, S.

    2006-03-01

    Polymer matrices have been suggested for effective trapping of uranium from seawater as the trapped uranium can be easily eluted and the polymer matrix can be reused for further trapping of uranium for several cycles. Such polymer matrices have been synthesized by incorporating specific groups into some polymer backbones, which brings about changes in the physicochemical properties of parent polymer backbone and makes it suitable for uptake of uranium. Graft co-polymerization is a suitable means of incorporating desirable groups into parent polymer matrix without drastically affecting the basic properties of the substrate. Radiation grafting has proven to be an easy, reproducible and versatile technique for grafting in comparison to chemical grafting. Development of radiation-grafted copolymers for the purpose of uranium recovery from seawater has been in progress at BARC during last few years. This report describes the work carried out on radiation grafting of acrylonitrile onto thermally bonded non-woven porous polypropylene fiber sheets using electron beam irradiation by post-irradiation grafting technique. The effect of various experimental variables viz. substrate material, form of substrate material, radiation source, grafting technique, grafting dose, dose rate, temperature, grafting solution composition etc. on grafting have been reported. Grafting extent of ∼125% using technical grade chemical were achieved. The grafted nitrile groups were subsequently converted to amidoxime group by chemical treatment. (author)

  11. Fixed prosthetic treatment in patients with cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Bajevska Jagoda

    2017-01-01

    Full Text Available Introduction. The prosthetic treatment of patients with cleft palate includes various treatment options such as fixed partial dentures, removable partial prosthesis, etc. The type of prosthetic appliance is determined by the oral health of each individual and the circumstances. We presented three adult patients with the cleft lip and palate subjected to prosthetic treatment. Case report. From the possible prosthetic solutions according to the conditions in the oral cavity and the circumstances, fixed partial dentures veneered with composite or ceramic were chosen. A proper relationship between the teeth was reached with the fixed partial dentures, and function established, the phonetics improved and satisfying aesthetics effect accomplished improving the profile appearance of the patient’s face. Plastic surgery of the nose was performed after that. Conclusion. Multidisclipinary treatment is necessary for favourable long-term outcome in cleft lip and palate patients.

  12. Antithrombotic Therapy in Patients with Prosthetic Heart Valves

    Directory of Open Access Journals (Sweden)

    Mohamed HA

    2009-01-01

    Full Text Available Patients with mechanical valve prostheses require a lifelong anticoagulant treatment. The combined use of Warfarin and low-dose aspirin appears to reduce the risk of valve thrombosis and systemic embolism at a low risk of bleeding. The management of women with prosthetic heart valves during pregnancy poses a particular challenge, as there are no available controlled clinical trials to provide guidelines for effective antithrombotic therapy. Oral anticoagulants, such as Warfarin, cause foetal embryopathy; unfractionated heparin and low-molecular-weight heparin have been reported to be ineffective in preventing thromboembolic complications.This article discusses the available data and the most recent guidelines in the antithrombotic management of patients with prosthetic valves, and antithrombotic therapy in various clinical situations such as pregnant women with prosthetic heart valves, and patients with prosthetic heart valves undergoing noncardiac surgery.

  13. Prosthetic Rehabilitation of Amputated Thumb: A Simplified Approach.

    Science.gov (United States)

    Agrawal, Kaushal Kishor; Aggarawal, Himanshi; Singh, Kamleshwar

    2014-12-01

    This case report presents a case of prosthetic rehabilitation of an amputated thumb. It emphasizes that prosthetic replacement is a better option for aesthetic and psychological improvement, particularly in cases where the victim is unwilling to undergo complicated surgical procedures for reconstruction of thumb or where functioning of thumb cannot be restored even by multiple surgeries. In the present case, a 20 years old female patient, with missing thumb of her right hand was rehabilitated aesthetically by a non-invasive and cost effective prosthetic procedure by using heat temperature vulcanizing silicone material. The prosthesis (the thumb) was attached using medical adhesives. On 3 months recall appointment, no complications were observed. The prosthesis was in good shape and required no further intervention. The prosthetic thumb lacks the sensation of a normal or reconstructed thumb, although it does not require the multiple procedures of surgical reconstruction and the accompanying loss of time for rehabilitation and healing.

  14. Skin and bone integrated prosthetic pylon: A pilot animal study

    OpenAIRE

    Pitkin, Mark; Raykhtsaum, Grigory; Galibin, Oleg V.; Protasov, Mikhail V.; Chihovskaya, Julie V.; Belyaeva, Irina G.

    2006-01-01

    Direct skeletal attachment of limb prostheses is a viable alternative to traditional techniques that are based on a socket-residuum interface. Direct skeletal attachment may be a better or even the only method for patients with a very short residuum and high soft-tissue volume. The problem of integrating the prosthetic pylon with residual skin during direct skeletal attachment of a limb prosthesis has not been solved, and the use of a completely porous prosthetic pylon has not been the subjec...

  15. Possibilities of prosthetic upper limb fitting in cycling

    OpenAIRE

    Doležalová, Hana

    2011-01-01

    Bachelor thesis give an overview of possible solutions in upper limbs prosthetic fitting which is suitable for cycling. And provide enough information on modifications that should be performed on a bicycle so that it can be used by humans with upper extremity prostheses. It can be an essential guide for anyone looking for a solution that would allow a person with an amputated upper limb again sit on the bike. Keywords: amputation, upper limb prosthesis, prosthetic fitting, cycling

  16. [Prevention of complications fixed restorations in prosthetic patients with hypertension].

    Science.gov (United States)

    2014-04-01

    The author on the basis of clinical and laboratory methods justified, that the use of locally cream "Solcoseryl-Denta" persons suffering from arterial hypertension, increase the speed of recovery of normal epithelial layer of the cells of the mucous membranes of the oral cavity, and, consequently, prevents the development of complications in prosthetics. On the basis of research identified the need in developing a method of prevention of inflammatory complications in prosthetic patients with arterial hypertension.

  17. Case Study and Review: Treatment of Tricuspid Prosthetic Valve Thrombosis

    OpenAIRE

    Yi Zhang, David; Lozier, Jay; Chang, Richard; Sachdev, Vandana; Chen, Marcus Y.; Audibert, Jennifer L.; Horvath, Keith A.; Rosing, Douglas R.

    2011-01-01

    Prosthetic valve thrombosis (PVT) is a severe and life-threatening complication of heart valve replacement. Conventional therapy is surgical thrombectomy or valve replacement. Medical thrombolysis is another emerging option. We report the case of a 57 year old woman with a history of Ebstein anomaly who underwent successful treatment of a tricuspid prosthetic valve thrombosis with intra-atrial infusion of very low dose recombinant tissue plasminogen activator (tPA). We review the presentation...

  18. Prosthetic Tricuspid Valve Thrombosis: Three Case Reports and Literature Review

    OpenAIRE

    Ahmad Yaminisharif; MohammadJavad Alemzadeh-Ansari; SeyedHossein Ahmadi

    2015-01-01

    A common complication of prosthetic heart valves is thrombosis. Although the incidence of prosthetic valve thrombosis (PVT) in the tricuspid position is high, there are not enough data on the management of it, in contrast to left-sided PVT. Here, we describe three cases of tricuspid PVT with three different management approaches: thrombolytic therapy; close observation with oral anticoagulants; and surgery. The first case was a woman who suffered from recurrent PVT, for which we successfully ...

  19. ORAL HYGIENE OF PROSTHETIC DENTURE USER IN KODINGARENG ISLAND

    OpenAIRE

    NUR, NURUL KUSUMADEWI S.KG

    2008-01-01

    Objectives:to determine the level of oral hygiene for prosthetic denture user, especially for full-denture in Kodingareng Island. This researchincluded the distribution level of prosthetic denture user based on age and education.Methods: the method that used in this research is observational descriptive withcross sectional-studyas the research design. Variable result of the research determined in to 3, those are bad, middle, and good. Result:the highest percentage o...

  20. Suction blister grafting - Modifications for easy harvesting and grafting

    Directory of Open Access Journals (Sweden)

    2012-01-01

    Full Text Available Suction blister grafting is a simple modality of treatment of patients with resistant and stable vitiligo. But raising the blisters may be time consuming and transferring to the recipient site may be difficult as the graft is ultrathin. By doing some modifications we can make the technique simpler and easier. We can decrease the blister induction time by intradermal injection of saline, exposure to Wood′s lamp, intrablister injection of saline. By these methods we can decrease the blister induction time from 2-3 hrs to 45-90 minutes. After harvesting the graft, it can be transferred to the recipient area by taking the graft on a sterile glass slide, on the gloved finger, rolling the graft over a sterile syringe and then spreading on the recipient area, or taking on the sterile wrapper of paraffin dressing and then placing over the recipient area.

  1. A review of available prosthetics for ventral hernia repair.

    Science.gov (United States)

    Shankaran, Vidya; Weber, Daniel J; Reed, R Lawrence; Luchette, Fred A

    2011-01-01

    To review mesh products currently available for ventral hernia repair and to evaluate their efficacy in complex repair, including contaminated and reoperative fields. Although commonly referenced, the concept of the ideal prosthetic has never been fully realized. With the development of newer prosthetics and approaches to the ventral hernia repair, many surgeons do not fully understand the properties of the available prosthetics or the circumstances that warrant the use of a specific mesh. A systematic review of published literature from 1951 to June of 2009 was conducted to identify articles relating to ventral hernia repairs and the use of prosthetics in herniorrhaphy. Important differences exist between the synthetics, composites, and biologic prosthetics used for ventral hernia repair in terms of mechanics, cost, and the ideal situation in which each should be used. The use of synthetic mesh remains an appropriate solution for most ventral hernia repairs. Laparoscopic ventral hernia repair has created a niche for both expanded polytetrafluoroethylene and composite mesh, as they are suited to intraperitoneal placement. Preliminary studies have demonstrated that the newer biologic prosthetics are reasonable options for hernia repair in contaminated fields and for large abdominal wall defects; however, more studies need to be done before advocating the use of these biologics in other settings.

  2. Rotationplasty with Vascular Reconstruction for Prosthetic Knee Joint Infection

    Directory of Open Access Journals (Sweden)

    Masahide Fujiki

    2015-01-01

    Full Text Available Rotationplasty is used most often as a function-preserving salvage procedure after resection of sarcomas of the lower extremity; however, it is also used after infection of prosthetic knee joints. Conventional vascular management during rotationplasty is to preserve and coil major vessels, but recently, transection and reanastomosis of the major vessels has been widely performed. However, there has been little discussion regarding the optimal vascular management of rotationplasty after infection of prosthetic knee joints because rotationplasty is rarely performed for this indication. We reviewed four patients who had undergone resection of osteosarcomas of the femur, placement of a prosthetic knee joint, and rotationplasty with vascular reconstruction from 2010 to 2013. The mean interval between prosthetic joint replacement and rotationplasty was 10.4 years and the mean interval between the diagnosis of prosthesis infection and rotationplasty was 7.9 years. Rotationplasty was successful in all patients; however, in one patient, arterial thrombosis developed and necessitated urgent surgical removal and arterial reconstruction. All patients were able to walk independently with a prosthetic limb after rehabilitation. Although there is no consensus regarding the most appropriate method of vascular management during rotationplasty for revision of infected prosthetic joints, vascular transection and reanastomosis is a useful option.

  3. Instantaneous stiffness and hysteresis of dynamic elastic response prosthetic feet.

    Science.gov (United States)

    Webber, Christina M; Kaufman, Kenton

    2017-10-01

    Dynamic elastic response prosthetic feet are designed to mimic the functional characteristics of the native foot/ankle joint. Numerous designs of dynamic elastic response feet exist which make the prescription process difficult, especially because of the lack of empirical evidence describing the objective performance characteristics of the feet. To quantify the mechanical properties of available dynamic elastic response prosthetic feet, specifically the stiffness and hysteresis. Mechanical testing of dynamic elastic response prosthetic feet. Static Proof Testing in accordance with ISO 10328 was conducted on seven dynamic elastic response prosthetic feet. Load-displacement data were used to calculate the instantaneous stiffness in both the heel and forefoot regions, as well as hysteresis associated with each foot. Heel stiffness was greater than forefoot stiffness for all feet. The heel of the glass composite prosthetic foot was stiffer than the carbon fiber feet and it exhibited less hysteresis. Two different carbon fiber feet had the stiffest forefoot regions. Mechanical testing is a reproducible method that can be used to provide objective evidence about dynamic elastic response prosthetic foot performance and aid in the prescription process. Clinical relevance The quantitative stiffness and hysteresis data from this study can be used by prosthetists to aid the prescription process and make it more objective.

  4. Predictive factors for better bypass patency and limb salvage after prosthetic above-knee bypass reconstruction.

    Science.gov (United States)

    Klingelhoefer, Eric; Bergert, Hendrik; Kersting, Stephan; Ludwig, Stefan; Weiss, Norbert; Schönleben, Frank; Grützmann, Robert; Gäbel, Gabor

    2016-08-01

    Peripheral arterial disease (PAD) is one of the most underestimated diseases because of its high prevalence and unfavorable prognosis. Many PAD patients without suitable autologous veins or options for endovascular treatment receive prosthetic above-knee femoropopliteal bypass (PAKB). Until now predictors of prosthetic bypass failure and of increased amputation risk remain indistinct. This study aimed to identify predictive factors associated with better bypass patency and limb salvage to achieve a more favorable outcome after PAKB reconstruction. Pre-, intra-, and postoperative data of 244 PAKB procedures performed at a German university medical center were collected and analyzed using univariate and multivariate methods. To our knowledge this 12-year experience is the largest retrospective study to identify predictors for patency and limb salvage after PAKB reconstruction. Of the PAD patients 94% (229/244) were followed for an average of 34.9 months. Patient cohorts characteristics were: mean age, 66.1 years, 181 men (74%), claudication (64%), rest pain (16%), ischemic lesions (20%), arterial hypertension (92%), smoking (79%), hyperlipidemia (65%) and type 2 diabetes (43%). Cumulative primary 1- and 3-year graft patency rates were 60.8% and 50.7%, respectively, and cumulative 1- and 3-year limb salvage rates were 89.3% and 86.1%, respectively. One hundred seven bypasses (43.9%) failed, 26 patients (10.7%) required a major and seven patients (2.9%) required a minor amputation. Overall survival rates of PAD patients after 1- and 3-years were 94.4% and 82.9%, respectively. Subjective symptom improvement was found to be the most important prognostic follow-up factor for graft patency and limb salvage. Patients with recurrent symptoms in the follow-up had an increased risk of emerging bypass failure compared with patients with subjective symptom improvement (patency at 1 year: 40.8% vs 100% and at 3 years: 26% vs 100%; P limb salvage at 1 year: 100% vs 79% and

  5. Characterization of materials for prosthetic implants using the BEAMnrc Monte Carlo code

    International Nuclear Information System (INIS)

    Spezi, E; Palleri, F; Angelini, A L; Ferri, A; Baruffaldi, F

    2007-01-01

    Metallic implants degrade image quality and perturb severely the patient dose distribution in external beam radiotherapy. Furthermore, conventional treatment planning systems (TPS) do not accurately account for tissue heterogeneities, especially at the interfaces where high Z gradients are present. This work deals with the accurate and systematic characterization of materials used for prosthetic implants. The dose calculation engine used in this investigation is the BEAMnrc Monte Carlo code. A detailed comparison versus experimental data was carried out for two clinical photon beam energies (6MV and 18MV). Our results show that in both cases a very good agreement (within ± 2%) between calculations and experiments was achieved

  6. [Prosthetics and Orthotics: Prosthetic Fitting in Lower Extremity in Transfemoral Amputation].

    Science.gov (United States)

    Greitemann, Bernhard

    2017-12-01

    Modern prosthetic equipment often enables reintegration of patients with the amputation of a lower limb into their private life, their professional and social environment to a large extent. Provisioning of the lower extremity with artificial limbs aims at a life as normal as possible for the involved individual. The modules are selected in an interdisciplinary team. An optimal fitting of the socket, the correct static set-up, the appropriate fitting as well as cosmetic aspects are the essential basis for a sufficient provisioning. Knee and foot components should be chosen according to the individual patient's situation including their prognostic mobility classification. Georg Thieme Verlag KG Stuttgart · New York.

  7. Bone grafting options in children.

    Science.gov (United States)

    Betz, Randal R; Lavelle, William F; Samdani, Amer F

    2010-08-01

    Retrospective review of the literature. To review the current literature as well as recent trends in bone grafting techniques available for children. The currently accepted gold standard in bone grafting for adolescent idiopathic scoliosis (AIS) is autogenous iliac crest. Due to questions concerning complications such as donor site pain, other options have been explored, including various allograft sources, demineralized bone matrix, and bone morphogenetic protein. A review of the current medical literature was completed and additional case examples are presented. A review of the literature reveals that up to 31% of patients have persistent pain at 2 years post surgery when autogenous iliac crest bone graft is harvested. Allograft supplementation of local autograft has been demonstrated in the literature to be as effective as autogenous iliac crest bone grafting in contributing to a successful posterior spinal fusion in patients with AIS. Modern demineralized bone matrix formulations have been found in both animal models as well as in a recent retrospective clinical review to contribute to a successful posterior spinal fusion in AIS. Bone morphogenetic protein has been shown to contribute to a successful posterior spinal fusion in complex pediatric spinal deformity patients. At 2 years follow-up, patients who underwent a posterior instrumented spinal fusion that was not augmented with any bone graft appear to have successful spinal fusions. Although autogenous iliac bone graft remains the benchmark to which bone grafting materials are compared, other options including the placement of no bone graft at all provides similar fusion rates in patients with AIS.

  8. Prosthetic Status and Prosthetic Need Among the Patients Attending Various Dental Institutes of Ahmedabad and Gandhinagar District, Gujarat

    OpenAIRE

    Shah, Vrinda R.; Shah, Darshana N.; Parmar, Chaitanya H.

    2012-01-01

    The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment ...

  9. Analytical Study of Active Prosthetic Legs

    Science.gov (United States)

    Ono, Kyosuke; Katsumata, Mie

    Walking with prosthesis has not been well analyzed mathematically and it seems that the design of powered prosthesis has been done empirically so far. This paper presents a dynamic simulation of a normal human walking and walking with an active prosthesis. We also studied the two controlling methods of a powered thigh prosthesis based on multi-body simulation of human walking. First we measured the normal human walking gait, then, we showed that a 3-DOF human walking model can walk on level ground by applying tracking control to the measured walking gait within a certain range of tuned walking period. Next, we applied the tracking control and self-excited control to the powered thigh prosthesis and compared the robustness and efficiency of the two control methods by numerical simulation. As a result, we found that the self-excited control can significantly decrease the hip joint torque and specific cost to 1/3 compared with the tracking control. Moreover, the self-excited control is superior to the tracking control because tuning for the walking period is not needed for the active prosthetic leg.

  10. Surface EMG in advanced hand prosthetics.

    Science.gov (United States)

    Castellini, Claudio; van der Smagt, Patrick

    2009-01-01

    One of the major problems when dealing with highly dexterous, active hand prostheses is their control by the patient wearing them. With the advances in mechatronics, building prosthetic hands with multiple active degrees of freedom is realisable, but actively controlling the position and especially the exerted force of each finger cannot yet be done naturally. This paper deals with advanced robotic hand control via surface electromyography. Building upon recent results, we show that machine learning, together with a simple downsampling algorithm, can be effectively used to control on-line, in real time, finger position as well as finger force of a highly dexterous robotic hand. The system determines the type of grasp a human subject is willing to use, and the required amount of force involved, with a high degree of accuracy. This represents a remarkable improvement with respect to the state-of-the-art of feed-forward control of dexterous mechanical hands, and opens up a scenario in which amputees will be able to control hand prostheses in a much finer way than it has so far been possible.

  11. Prosthetic rehabilitation of the upper limb amputee

    Directory of Open Access Journals (Sweden)

    Bernard O′Keeffe

    2011-01-01

    Full Text Available The loss of all or part of the arm is a catastrophic event for a patient and a significant challenge to rehabilitation professionals and prosthetic engineers. The large, upper extremity amputee population in India has, historically, been poorly served, with most having no access to support or being provided with ineffective prostheses. In recent years, the arrival of organisations like Otto Bock has made high quality service standards and devices accessible to more amputees. This review attempts to provide surgeons and other medical professionals with an overview of the multidisciplinary, multistage rehabilitation process and the solution options available. With worldwide upper extremity prosthesis rejection rates at significant levels, the review also describes some of the factors which influence the outcome. This is particularly relevant in the Indian context where the service can involve high cost investments. It is the responsibility of all contributing professionals to guide vulnerable patients through the process and try to maximise the benefit that can be obtained within the resources available.

  12. Consumer design priorities for upper limb prosthetics.

    Science.gov (United States)

    Biddiss, Elaine; Beaton, Dorcas; Chau, Tom

    2007-11-01

    To measure consumer satisfaction with upper limb prosthetics and provide an enumerated list of design priorities for future developments. A self-administered, anonymous survey collected information on participant demographics, history of and goals for prosthesis use, satisfaction, and design priorities. The questionnaire was available online and in paper format and was distributed through healthcare providers, community support groups, and one prosthesis manufacturer; 242 participants of all ages and levels of upper limb absence completed the survey. Rates of rejection for myoelectric hands, passive hands, and body-powered hooks were 39%, 53%, and 50%, respectively. Prosthesis wearers were generally satisfied with their devices while prosthesis rejecters were dissatisfied. Reduced prosthesis weight emerged as the highest priority design concern of consumers. Lower cost ranked within the top five design priorities for adult wearers of all device types. Life-like appearance is a priority for passive/cosmetic prostheses, while improved harness comfort, wrist movement, grip control and strength are required for body-powered devices. Glove durability, lack of sensory feedback, and poor dexterity were also identified as design priorities for electric devices. Design priorities reflect consumer goals for prosthesis use and vary depending on the type of prosthesis used and age. Future design efforts should focus on the development of more light-weight, comfortable prostheses.

  13. Allogeneic bone marrow grafts in genotyped swine

    International Nuclear Information System (INIS)

    Vaiman, M.

    1974-01-01

    The proof of a major histocompatibility complex (MHC) called SL-A enabled to promote bone marrow allografts. A study of the response to that kind of graft in irradiated pig states a number of interesting points. Bone marrow allografting complies with the rule of tissular compatibility with the major histocompatibility complex. The taking of SL-A incompatible bone marrow allografts could not be achieved under the experimental conditions. In spite of the high doses of radiation, 950 to 1050 rads, higher than 1.5 LD 100%, recipients were capable of rejecting their grafts, regularly. SL-A identify ensured 100%, initial achievement. However, animals developed regular fatal disease within a fairly short time. This development could by no means, be ascribed to the sole sequealae of radiation sickness since autografted animals at equal or even higher doses, showed none of the symptome. Assumption of a chronic graft-vs-host reactions, induced by the minor histocompatible systems, was put foreward, but should be confirmed histopathologically [fr

  14. Radiation grafting on natural films

    Science.gov (United States)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37-40 N mm-1) and puncture deformation (PD=6.5-9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282-296 N mm-1 and PD of 5.0-5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films.

  15. Neointima development in externally stented saphenous vein grafts

    Directory of Open Access Journals (Sweden)

    Przemysław Węglarz

    2016-11-01

    Full Text Available Introduction : The main limitation of coronary artery bypass grafting (CABG is rapid neointimal hyperplasia leading to graft failure. Aim : To assess plaque formation in saphenous vein grafts (SVG covered by an external Dacron stent in comparison with the classical technique. Material and methods : In the study group vein grafts covered by external stent mesh made of Dacron were implanted. An intravascular ultrasonography (IVUS study was performed in 35 aorto-coronary SVG covered by an external Dacron stent and in 64 normal SVG during the first year after CABG. In each SVG 25 mm of good quality IVUS image, volumes of lumen, plaque (neointima, outer border of the vein graft (external SVG and adventitia were calculated in three time periods: 0–130 days, 130–260 days and 260–390 days. Results : Between the first and second time period, lumen volume (mm3 was reduced from 10.33 ±4.4, to 6.80 ±2.23 in the second period and 5.69 ±1.26 in the third one. This effect was much less marked in normal grafts. The corresponding lumen volume (mm3 was: 10.90 ±3.9, 9.15 ±2.94 and 8.92 ±2.93 in consecutive time periods. Plaque volume (mm3 did not change in control grafts during the course of the study, but it increased very significantly in stented grafts from 0.86 ±1.24 in the first period to 2.70 ±1.58 in the second and 3.29 ±2.66 in the third one. Conclusions : The experimental technique of implanting SVG covered with an external elastic Dacron stent seems to be inferior to traditional ones. This is probably due to the more complicated process of vein implantation and higher micro-injury occurrence during the surgery.

  16. A Novel Technique of Fabricating a Modified Removable Provisional Prosthesis over an Autologous Bone Grafted Maxillary Anterior Edentulous Segment Prior to Implant Placement.

    Science.gov (United States)

    Andonissamy, Leoney; Vidhya, N Sri

    2017-09-01

    Implant dentistry has provided a lot of surgical as well as prosthetic techniques for improving the success of the implants. The surgical technique commonly followed now prior to implant placement is bone grafting procedure. One of the commonest techniques is the use of autologous block graft harvested from mandibular chin region. However, interference in healing as well as excessive bone resorption due to the use of removable provisional prosthesis over the bone grafted region has been commonly observed/reported. Hence now-a-days, fixed provisional prosthesis is preferred over removable provisional prosthesis for the added advantages of superior aesthetics and patient acceptance. This article highlights a new technique of fabricating removable provisional prosthesis, which is superior in aesthetics and strength, consumes less chair time and exerts zero pressure onto the grafted site.

  17. Prosthetic aortic valve selection: current patient experience, preferences and knowledge

    Science.gov (United States)

    Korteland, Nelleke M; Bras, Frans J; van Hout, Fabienne M A; Kluin, Jolanda; Klautz, Robert J M; Bogers, Ad J J C; Takkenberg, Johanna J M

    2015-01-01

    Objective Current clinical practice guidelines advocate shared decision-making (SDM) in prosthetic valve selection. This study assesses among adult patients accepted for aortic valve replacement (AVR): (1) experience with current clinical decision-making regarding prosthetic valve selection, (2) preferences for SDM and risk presentation and (3) prosthetic valve knowledge and numeracy. Methods In a prospective multicentre cohort study, AVR patients were surveyed preoperatively and 3 months postoperatively. Results 132 patients (89 males/43 females; mean age 67 years (range 23–86)) responded preoperatively. Decisional conflict was observed in 56% of patients, and in 25% to such an extent that it made them feel unsure about the decision. 68% wanted to be involved in decision-making, whereas 53% agreed that they actually were. 69% were able to answer three basic knowledge questions concerning prosthetic valves correctly. 56% were able to answer three basic numeracy questions correctly. Three months postsurgery, 90% (n=110) were satisfied with their aortic valve prosthesis, with no difference between mechanical and bioprosthetic valve recipients. Conclusions In current clinical practice, many AVR patients experience decisional conflict and suboptimal involvement in prosthetic valve selection, and exhibit impaired knowledge concerning prosthetic valves and numeracy. Given the broad support for SDM among AVR patients and the obvious need for understandable information, to-be-developed tools to support SDM in the setting of prosthetic valve selection will help to improve quality of decision-making, better inform and actively involve patients, and reduce decisional conflict. Trial registration number NTR3618. PMID:25893105

  18. [Vacuum sealing drainage combined with free skin graft in repairing cutaneous deficiency of traumatic shank amputation stump].

    Science.gov (United States)

    Zhao, Xiao-fei; Li, Chun-you; Jin, Guo-qiang; Ming, Xiao-feng; Wang, Guo-jie

    2014-12-01

    To observe clinical efficacy in treating cutaneous deficiency of traumatic shank amputation stump with full-thickness skin graft combined with vacuum sealing drainage. From September 2009 to December 2012, 15 patients with cutaneous deficiency of traumatic shank amputation stump were treated with full-thickness skin graft combined with vacuum sealing drainage. Among patients, there were 11 males and 4 females with an average age of 41.5 (ranged from 25 to 62) years old. Ten cases were caused by traffic accident and 5 cases were caused by heavy object, 9 cases on left and 6 cases on right. Six patients with smashed wound were treated with debridement and amputation, combined with vacuum aspiration in-emergency; 9 patients caused by infection and necrosis were treated with debridement and amputation, combined with vacuum aspiration, and full-thickness skin graft were performed at stage II. The skin defect area of residual limbs ranged from 40 cm x 20 cm to 25 cm x 15 cm. All patients were followed up from 3 months to 1 year. Full-thickness skin graft of residual limbs were survived,and obtained satisfactory walking function with prosthetic. Residual skin increased thicken, wearproof without rupture and pain. Full-thickness skin graft combined with vacuum sealing drainage in treating cutaneous deficiency of traumatic shank amputation stump could reserve the length of residual limbs, increase survival rate of skin graft with less scar of survival skin, get good wearability and it is conducive to prosthetic wear. It is a simple and easy treatment method.

  19. A novel method of defective vascular reconstruction using 2-octyl-cyanoacrylate and homemade prosthetic component.

    Science.gov (United States)

    Liang, Xiangdang; Cai, Hongfei; Sun, Geng; Liu, Zihao; Chen, Wen; Tang, Peifu

    2014-01-01

    Currently, adhesive technique is popular in vascular repair but not widely used for defective vessels. This study aimed to determine the feasibility and effectiveness of repairing defective vessels with 2-octyl-cyanoacrylate and a homemade prosthetic component. Homemade prosthetic component consisting of expanded polytetrofluoroethylene (ePTFE), terylene film, and homemade soluble hollow stent mixed with adhesive can replace autologous graft and suture in repairing defective vessels, can fix vessels better using the stent without occlusive bleeding. Forty male mongrel dogs were used, 20 for biomechanical tests and 20 for animal experiments. In the biomechanical test, dogs were randomly divided into two groups (n = 10 each), one group repaired on the two sides of the carotid arteries with 2-octyl-cyanoacrylate and homemade component and another group repaired with suture and ePTFE. Of the 40 specimens, 10 were used for adhesive and 10 for suture specimens for tension strength test, whereas the remaining specimens were used for bursting pressure test. In animal experiments, dogs were also divided into adhesive and suture groups (n = 10), only of the left carotid artery. Recording the operational time, bleeding or not. Vessels were tested using color Doppler ultrasound, the inner diameter was measured, and the degree of stenosis at 8 weeks was evaluated digital subtraction angiography (DSA) were also performed. Specimens were then analyzed histologically. In the adhesive and suture groups, the specimens could afford atension strength of (23.80 ± 1.51) N versus (24.60 ± 1.08) N (P > 0.05), the bursting pressure was (52.03 ± 2.43) kPa versus (50.04 ± 3.51) kPa (P > 0.05), and the mean time of anastomosis was (15.20 ± 0.55) minutes versus (25.97 ± 0.58) minutes (P < 0.05). One dog in the adhesive group was bleeding from the suture. One dog from each group presented with thrombosis at 1 week. After measuring using ultrasound, the stenosis degree of all dogs were no

  20. Prescription and repair rates of prosthetic limbs in the VA healthcare system: implications for national prosthetic parity.

    Science.gov (United States)

    Etter, Katherine; Borgia, Matthew; Resnik, Linda

    2014-05-22

    Abstract Purpose: To quantify prescription and repair rates of prosthetic limbs in the Department of Veterans Affairs (VA) and explore differences by level, type, and age. Methods: Veterans (N = 32 440) with an initial prosthetic prescription between 2000 and 2010 were classified by amputation level and type. Annual rates of prescription and repair were calculated using person-time and compared by group. Results: Veterans with upper limb amputation had lower annual prescription and repair rates (0.28 and 0.21) compared with those with lower limb amputation (0.40 and 0.56). Myoelectric devices users had higher prescription rates. However, body-powered users had higher repair rates. Prescription and repair rates for microprocessor knee joints were higher than for fluid and friction devices. Veterans under 65 had 0.07 and 0.16 higher rates of prescription and repair than those over 65 (p < 0.0001). Conclusions: Because the VA is unconstrained by co-pays or caps, data on prosthetic prescription and repair can be used to estimate rates that might occur if national prosthetic parity laws were adopted. Given the rates found, it is likely that annual costs would exceed the typical annual and/or lifetime caps in most insurance plans. In states without prosthetic parity laws, such costs likely limit access to needed devices. Implications for Rehabilitation For the almost 2 million people in the United States living with an amputation or congenital limb loss, purchasing and maintaining a prosthetic limb can be costly, with insurances often imposing annual or lifetime caps. Data on prosthetic purchasing and repair is limited and reliant on self-reported information. Because the VA is unconstrained by co-pays or caps, claims data on prosthetic prescription and repair can be used to estimate rates that might occur if national prosthetic parity laws were adopted. Given the rates found, it is likely that annual costs would exceed the typical annual and/or lifetime caps

  1. Graft intolerance syndrome requiring graft nephrectomy after late kidney graft failure: can it be predicted? A retrospective cohort study.

    Science.gov (United States)

    Bunthof, Kim L W; Verhoeks, Carmen M; van den Brand, Jan A J G; Hilbrands, Luuk B

    2018-02-01

    Graft nephrectomy is recommended in case of early graft failure. When the graft fails more than 3-6 months after transplantation, it is current practice to follow a wait-and-see policy. A common indication for graft removal is the graft intolerance syndrome. We aimed to create a risk prediction model for the occurrence of graft intolerance resulting in graft nephrectomy. We collected data of kidney transplantations performed in our center between 1980 and 2010 that failed at least 6 months after transplantation. We evaluated the association between baseline characteristics and the occurrence of graft nephrectomy because of graft intolerance using a competing risk regression model. Prognostic factors were included in a multivariate prediction model. In- and exclusion criteria were met in 288 cases. In 48 patients, the graft was removed because of graft intolerance. Donor age, the number of rejections, and shorter graft survival were predictive factors for graft nephrectomy because of the graft intolerance syndrome. These factors were included in a prediction rule. Using donor age, graft survival, and the number of rejections, clinicians can predict the need for graft nephrectomy with a reasonable accuracy. © 2017 Steunstichting ESOT.

  2. Immediate loading of dental implants placed in severely resorbed edentulous maxillae reconstructed with Le Fort I osteotomy and interpositional bone grafting.

    Science.gov (United States)

    Pieri, Francesco; Lizio, Giuseppe; Bianchi, Alberto; Corinaldesi, Giuseppe; Marchetti, Claudio

    2012-08-01

    Reconstruction and rehabilitation of atrophic maxillae with bone grafts is a lengthy and demanding procedure. This study reports the immediate loading of 50 implants placed on six extremely atrophied edentulous maxillae reconstructed with Le Fort I osteotomy and iliac bone grafting. Six patients, aged 49 to 68 years, with severely atrophied maxillae were treated with Le Fort I osteotomy and iliac bone grafting to allow for implant-borne prosthetic rehabilitation. Four to 5 months thereafter, 50 implants (seven to 10 per patient) were placed in reconstructed maxillae and immediately functionally loaded with a screw-retained definitive prosthesis. The patients were followed by clinical and radiographic examinations for 24 months after prosthetic loading. The grafting procedure and healing period before implant placement were uneventful in all patients. Two implants were lost within 2 months after prosthesis insertion in two patients, with an overall survival rate of 96%. The prostheses success rate was 100%. At the end of the follow-up period, all remaining implants appeared clinically healthy; crestal bone loss was >1.7 mm for six implants, resulting in a cumulative success rate of 84%. Immediate loading of implants placed after Le Fort I osteotomy and interpositional iliac bone grafting could be considered a viable protocol to rehabilitate extremely atrophied edentulous maxillae, considerably reducing the treatment time.

  3. Two-step grafting significantly enhances the survival of foetal dopaminergic transplants and induces graft-derived vascularisation in a 6-OHDA model of Parkinson's disease.

    Science.gov (United States)

    Büchele, Fabian; Döbrössy, Máté; Hackl, Christina; Jiang, Wei; Papazoglou, Anna; Nikkhah, Guido

    2014-08-01

    Following transplantation of foetal primary dopamine (DA)-rich tissue for neurorestaurative treatment of Parkinson's disease (PD), only 5-10% of the functionally relevant DAergic cells survive both in experimental models and in clinical studies. The current work tested how a two-step grafting protocol could have a positive impact on graft survival. DAergic tissue is divided in two portions and grafted in two separate sessions into the same target area within a defined time interval. We hypothesized that the first graft creates a "DAergic" microenvironment or "nest" similar to the perinatal substantia nigra that stimulates and protects the second graft. 6-OHDA-lesioned rats were sequentially transplanted with wild-type (GFP-, first graft) and transgenic (GFP+, second graft) DAergic cells in time interims of 2, 5 or 9days. Each group was further divided into two sub-groups receiving either 200k (low cell number groups: 2dL, 5dL, 9dL) or 400k cells (high cell number groups: 2dH, 5dH, 9dH) as first graft. During the second transplantation, all groups received the same amount of 200k GFP+ cells. Controls received either low or high cell numbers in one single session (standard protocol). Drug-induced rotations, at 2 and 6weeks after grafting, showed significant improvement compared to the baseline lesion levels without significant differences between the groups. Rats were sacrificed 8weeks after transplantation for post-mortem histological assessment. Both two-step groups with the time interval of 2days (2dL and 2dH) showed a significantly higher survival of DAergic cells compared to their respective standard control group (2dL, +137%; 2dH, +47%). Interposing longer intervals of 5 or 9days resulted in the loss of statistical significance, neutralising the beneficial two-step grafting effect. Furthermore, the transplants in the 2dL and 2dH groups had higher graft volume and DA-fibre-density values compared to all other two-step groups. They also showed intense growth of

  4. Staphylococcus capitis isolated from prosthetic joint infections.

    Science.gov (United States)

    Tevell, S; Hellmark, B; Nilsdotter-Augustinsson, Å; Söderquist, B

    2017-01-01

    Further knowledge about the clinical and microbiological characteristics of prosthetic joint infections (PJIs) caused by different coagulase-negative staphylococci (CoNS) may facilitate interpretation of microbiological findings and improve treatment algorithms. Staphylococcus capitis is a CoNS with documented potential for both human disease and nosocomial spread. As data on orthopaedic infections are scarce, our aim was to describe the clinical and microbiological characteristics of PJIs caused by S. capitis. This retrospective cohort study included three centres and 21 patients with significant growth of S. capitis during revision surgery for PJI between 2005 and 2014. Clinical data were extracted and further microbiological characterisation of the S. capitis isolates was performed. Multidrug-resistant (≥3 antibiotic groups) S. capitis was detected in 28.6 % of isolates, methicillin resistance in 38.1 % and fluoroquinolone resistance in 14.3 %; no isolates were rifampin-resistant. Heterogeneous glycopeptide-intermediate resistance was detected in 38.1 %. Biofilm-forming ability was common. All episodes were either early post-interventional or chronic, and there were no haematogenous infections. Ten patients experienced monomicrobial infections. Among patients available for evaluation, 86 % of chronic infections and 70 % of early post-interventional infections achieved clinical cure; 90 % of monomicrobial infections remained infection-free. Genetic fingerprinting with repetitive sequence-based polymerase chain reaction (rep-PCR; DiversiLab®) displayed clustering of isolates, suggesting that nosocomial spread might be present. Staphylococcus capitis has the potential to cause PJIs, with infection most likely being contracted during surgery or in the early postoperative period. As S. capitis might be an emerging nosocomial pathogen, surveillance of the prevalence of PJIs caused by S. capitis could be recommended.

  5. Vascularized bone grafting in a canine carpal avascular necrosis model

    NARCIS (Netherlands)

    Willems, Wouter F.; Alberton, Gregory M.; Bishop, Allen T.; Kremer, Thomas

    2011-01-01

    Limited experimental research has been performed on the treatment of avascular necrosis (AVN) by vascularized bone grafting. A new model simulating carpal AVN was created to investigate surgical revascularization of necrotic bone. In seven mongrel dogs, AVN was induced by removal of the radial

  6. CAD-CAM prosthetically guided bone regeneration using preformed titanium mesh for the reconstruction of atrophic maxillary arches.

    Science.gov (United States)

    Ciocca, L; Fantini, M; De Crescenzio, F; Corinaldesi, G; Scotti, R

    2013-01-01

    The protocol presented here is intended to minimise the intervention in bone reconstruction surgery when severe atrophy or deformity is present in the maxillary arches. A patient underwent augmentation of an atrophic maxillary arch using titanium mesh and particulate autogenous plus bovine demineralised bone. After computed tomography data elaboration, computer-aided design and computer-aided machining were used to plan the augmentation of bone volume to improve the implant position needed to support the final dental prosthesis. The augmented maxilla was rapidly prototyped in plastic, and the titanium mesh was tested on this model before the surgical intervention. Then, the preformed titanium mesh was implanted in the maxillary arch with bone grafting. The bone was augmented relative to the position of the implants for the definitive fixed implant-supported rehabilitation. The protocol presented here is a viable, reproducible way to determine the correct bone augmentation for the final implant-supported prosthetic rehabilitation.

  7. Graft nephrectomy: The SGPGI experience

    Directory of Open Access Journals (Sweden)

    Nand Kishore Arvind

    2002-01-01

    Full Text Available Background: Graft nephrectomy is often considered a hazardous procedure with high morbidity and occasional mortality, and this may pose a technical challenge. The aim of this study was to evaluate the indications, etiology and complications following graft nephrectomy. Materials and Methods: From 1988 to 2001, among total of 1,019 live related renal transplants carried at our center, 46 underwent graft nephrectomy. Patients were divided into 2 groups depending on timing of graft re-moval. The early group included 27 patients (within 2 months of transplantation while in late group (graft re-moval after 2 months of transplantation there were 19 patients. The 2 groups were compared in terms of indica-tion, etiology and complications. Results: In early group the indications for graft removal were acute rejection, thrombosis/infarction and hyper-acute rejection, while in late group the indications were pain, hematuria, fever, hypertension and infection along with chronic failure. Overall, the external iliac artery in-jury occurred in I and 4 patients in early and late group respectively. Major blood loss occurred in I and 6 pa-tients in early and late graft removal respectively. There were 2 deaths in early group due to ftdminant pneumoni-tis that progressed to sepsis and disseminated intravascu-lar coagulation. There were 9 major wound infections all in early group except in 2 patients of late group. Respira-tory infections occurred in 14 patients in early group and 1 in late group. In early group patients had CNS compli-cations in form of seizures, clinical depression and delusional psychosis in 12 patients. Conclusions: Our experience highlights the risk in-volved in graft nephrectomies. Severe acute rejection and thrombosis lead to early graft nephrectomies. Pain, hematuria, infection and hypertension in setting of chronic rejection are predominant causes for the delayed graft ne- phrectomies. Early graft nephrectomy, though technically easy, is

  8. Methods for characterization of mechanical and electrical prosthetic vacuum pumps.

    Science.gov (United States)

    Komolafe, Oluseeni; Wood, Sean; Caldwell, Ryan; Hansen, Andrew; Fatone, Stefania

    2013-01-01

    Despite increasingly widespread adoption of vacuum-assisted suspension systems in prosthetic clinical practices, there remain gaps in the body of scientific knowledge guiding clinicians' choices of existing products. In this study, we identified important pump-performance metrics and developed techniques to objectively characterize the evacuation performance of prosthetic vacuum pumps. The sensitivity of the proposed techniques was assessed by characterizing the evacuation performance of two electrical (Harmony e-Pulse [Ottobock; Duderstadt, Germany] and LimbLogic VS [Ohio Willow Wood; Mt. Sterling, Ohio]) and three mechanical (Harmony P2, Harmony HD, and Harmony P3 [Ottobock]) prosthetic pumps in bench-top testing. Five fixed volume chambers ranging from 33 cm(3) (2 in.(3)) to 197 cm(3) (12 in.(3)) were used to represent different air volume spaces between a prosthetic socket and a liner-clad residual limb. All measurements were obtained at a vacuum gauge pressure of 57.6 kPa (17 inHg). The proposed techniques demonstrated sensitivity to the different electrical and mechanical pumps and, to a lesser degree, to the different setting adjustments of each pump. The sensitivity was less pronounced for the mechanical pumps, and future improvements for testing of mechanical vacuum pumps were proposed. Overall, this study successfully offers techniques feasible as standards for assessing the evacuation performance of prosthetic vacuum pump devices.

  9. Hand Transplantation Versus Hand Prosthetics: Pros and Cons.

    Science.gov (United States)

    Salminger, S; Roche, A D; Sturma, A; Mayer, J A; Aszmann, O C

    Composite tissue transplantation and new developments in the field of prosthetics have opened new frontiers in the restoration of function among upper limb amputees. It is now possible to restore hand function in affected patients; however, the indications, advantages, and limitations for either hand transplantation or prosthetic fitting must be carefully considered depending on the level and extent of the limb loss. Hand transplantation allows comprehensive hand function to be restored, yet composite tissue transplantation comes with disadvantages, making this method a controversial topic in the hand surgical community. Alternatively, prosthetic limb replacement represents the standard of care for upper limb amputees, but results in the known limitations of function, sensation, and usage. The indication for hand transplantation or prosthetic fitting strongly depends on the level of amputation, as well as on the extent (unilateral/bilateral) of the amputation. In this review, we discuss the advantages and disadvantages of hand transplantation and prosthetic replacement for upper limb amputees in general, as well as in regard to the different levels of amputation.

  10. Heel-region properties of prosthetic feet and shoes.

    Science.gov (United States)

    Klute, Glenn K; Berge, Jocelyn S; Segal, Ava D

    2004-07-01

    The properties of the prosthetic components prescribed to amputees have the potential to ameliorate or exacerbate their comfort, mobility, and health. To measure the difference in heel-region structural properties of currently available prosthetic feet and shoes, we simulated the period of initial heel-ground contact with a pendulum apparatus. The energy dissipation capacity of the various prosthetic feet ranged from 33.6% to 52.6% of the input energy. Donning a shoe had a large effect. Energy dissipation of a Seattle Lightfoot 2 prosthetic foot was 45.3%, while addition of a walking, running, and orthopedic shoe increased energy dissipation to 63.0%, 73.0%, and 82.4%, respectively. The force versus deformation response to impact was modeled as a hardening spring in parallel with a position-dependent damping element. A nonlinear least-squares curve fit produced model coefficients useful for predicting the heel-region impact response of both prosthetic feet and shoes.

  11. Provision of Prosthetic Services Following Lower Limb Amputation in Malaysia

    Science.gov (United States)

    Arifin, Nooranida; Hasbollah, Hasif Rafidee; Hanafi, Muhammad Hafiz; Ibrahim, Al Hafiz; Rahman, Wan Afezah Wan Abdul; Aziz, Roslizawati Che

    2017-01-01

    The incidence of lower limb amputation is high across the globe and continues to be a major threat to morbidity and mortality. Consequently, the provision of high quality and effective prosthetics services have been known as an essential component for a successful rehabilitation outcome. In Malaysia, amputation prevalence has been increasing in which several main components of service delivering aspects (such as service intervention, prosthetic personnel) should be anticipated to accommodate for the increasing demand. This article highlights the hurdles experienced in providing prosthetic services in Malaysia from multiple aspects such as financial burden to acquire the prosthesis and lack of expertise to produce quality prosthesis. This paramount issues consequently justify for the urgency to carry out national level survey on the current statistics of lower limb amputation and to ascertain the available workforce to provide a quality prosthetics services. Only with accurate and current information from the national survey, strategies and policies aimed at enhancing the outcome from prosthetics services can be achieved. PMID:29386978

  12. Biomechanical design considerations for transradial prosthetic interface: A review.

    Science.gov (United States)

    Sang, Yuanjun; Li, Xiang; Luo, Yun

    2016-03-01

    Traditional function and comfort assessment of transradial prostheses pay scant attention to prosthetic interface. With better understanding of the biomechanics of prosthetic interface comes better efficiency and safety for interface design; in this way, amputees are more likely to accept prosthetic usage. This review attempts to provide design and selection criteria of transradial interface for prosthetists and clinicians. Various transradial socket types in the literature were chronologically reviewed. Biomechanical discussion of transradial prosthetic interface design from an engineering point of view was also done. Suspension control, range of motion, stability, as well as comfort and safety of socket designs have been considered in varying degrees in the literature. The human-machine interface design should change from traditional "socket design" to new "interface design." From anatomy and physiology to biomechanics of the transradial residual limb, the force and motion transfer, together with comfort and safety, are the two main aspects in prosthetic interface design. Load distribution and transmission should mainly rely on achieving additional skeletal control through targeted soft tissue relief. Biomechanics of the residual limb soft tissues should be studied to find the relationship between mechanical properties and the comfort and safety of soft tissues. © IMechE 2016.

  13. Provision of Prosthetic Services Following Lower Limb Amputation in Malaysia.

    Science.gov (United States)

    Arifin, Nooranida; Hasbollah, Hasif Rafidee; Hanafi, Muhammad Hafiz; Ibrahim, Al Hafiz; Rahman, Wan Afezah Wan Abdul; Aziz, Roslizawati Che

    2017-10-01

    The incidence of lower limb amputation is high across the globe and continues to be a major threat to morbidity and mortality. Consequently, the provision of high quality and effective prosthetics services have been known as an essential component for a successful rehabilitation outcome. In Malaysia, amputation prevalence has been increasing in which several main components of service delivering aspects (such as service intervention, prosthetic personnel) should be anticipated to accommodate for the increasing demand. This article highlights the hurdles experienced in providing prosthetic services in Malaysia from multiple aspects such as financial burden to acquire the prosthesis and lack of expertise to produce quality prosthesis. This paramount issues consequently justify for the urgency to carry out national level survey on the current statistics of lower limb amputation and to ascertain the available workforce to provide a quality prosthetics services. Only with accurate and current information from the national survey, strategies and policies aimed at enhancing the outcome from prosthetics services can be achieved.

  14. Graft union formation in Douglas-fir.

    Science.gov (United States)

    D.L. Copes

    1969-01-01

    Greenhouse-grown Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) graft unions were examined between 2 and 84 days after grafting. Room temperature was maintained at 60-70 F throughout the growing season. In most respects grafts of Douglas-fir followed development patterns previously reported for spruce and pine grafts, but specific differences...

  15. Grafting compatibility between selected rootstocks and Tanzanian ...

    African Journals Online (AJOL)

    The grafted seedlings with graft union tied using grafting clips were healed in a dark chamber for three days and then in a transparent chamber for three days. The average temperature and relative humidity in both chambers were maintained at 21-30°C and 85-95 %, respectively. The grafted seedlings were hardened for ...

  16. Saphenous vein graft vs. radial artery graft searching for the best second coronary artery bypass graft

    Science.gov (United States)

    Al-Sabti, Hilal Ali; Al Kindi, Adil; Al-Rasadi, Khalid; Banerjee, Yajnavalka; Al-Hashmi, Khamis; Al-Hinai, Ali

    2013-01-01

    Coronary artery bypass grafting (CABG) was first used in the late 1960s. This revolutionary procedure created hope among ischemic heart disease patients. Multiple conduits are used and the golden standard is the left internal mammary artery to the left anterior descending artery. Although all approaches were advocated by doctors, the use of saphenous vein grafts became the leading approach used by the majority of cardiac surgeons in the 1970s. The radial artery graft was introduced at the same time but was not as prevalent due to complications. It was reintroduced into clinical practice in 1989. The procedure was not well received initially but it has since shown superiority in patency as well as long-term survival after CABG. This review provides a summary of characteristics, technical features and patency rates of the radial artery graft in comparison with venous conduits. Current studies and research into radial artery grafts and saphenous vein grafts for CABG are explored. However, more studies are required to verify the various findings of the positive effects of coronary artery bypass grafting with the help of radial arteries on mortality and long-lasting patency. PMID:24198449

  17. [Skin defect coverage with micro skin graft].

    Science.gov (United States)

    Gümüş, Nazim; Kaya, Yalçin; Karakaya, Sadik; Camci, Cemalettin

    2002-04-01

    The aim of this study is to coverage of the large skin defect with microskin graft. The wound coverage of the large skin defect may be difficult with auto skin graft. In these patients, split thickness skin graft may be used in a bloc shape or expanded skin graft shape and a stamp skin graft shape or expanded stamp skin graft shape. On the other hand, split thickness skin graft may be used as a micrograft shape after the mincing process, which reduces of the graft size in a few millimeters. In this study, 6 patients with skin defect was admitted in our clinic, and their skin defect was treated with micro skin graft. Expansion ratio was 1:15. Epithelialization on the wound surface was completed in 4 to 6 weeks and cobblestone appearance was observed after the wound coverage. Skin defect coverage with micrograft is an effective technique like the other skin graft coverage methods.

  18. Structural Transitions of Solvent-Free Oligomer-Grafted Nanoparticles

    KAUST Repository

    Chremos, Alexandros

    2011-09-01

    Novel structural transitions of solvent-free oligomer-grafted nanoparticles are investigated by using molecular dynamics simulations of a coarse-grained bead-spring model. Variations in core size and grafting density lead to self-assembly of the nanoparticles into a variety of distinct structures. At the boundaries between different structures, the nanoparticle systems undergo thermoreversible transitions. This structural behavior, which has not been previously reported, deviates significantly from that of simple liquids. The reversible nature of these transitions in solvent-free conditions offers new ways to control self-assembly of nanoparticles at experimentally accessible conditions. © 2011 American Physical Society.

  19. LONG TERM EVOLUTION OF BONE RECONSTRUCTION WITH BONE GRAFT SUBSTITUTES

    Directory of Open Access Journals (Sweden)

    O. V. Martynenko

    2017-06-01

    Full Text Available The review involves clinical and experimental data, constitutive modeling, and computational investigations towards an understanding on how mechanical cyclic loads for long periods of time affect damage evolution in a reconstructed bone, as well as, lifetime reduction of bone graft substitutes after advanced core decompression. The outcome of the integrated model discussed in this paper will be how damage growth in femur after advanced core decompression subjected to mechanical cyclic loading under creep and fatigue conditions may be controlled in order to optimize design and processing of bone graft substitutes, and extend lifetime of bone substitutes.

  20. Dutch evidence-based guidelines for amputation and prosthetics of the lower extremity: Rehabilitation process and prosthetics. Part 2.

    Science.gov (United States)

    Geertzen, Jan; van der Linde, Harmen; Rosenbrand, Kitty; Conradi, Marcel; Deckers, Jos; Koning, Jan; Rietman, Hans S; van der Schaaf, Dick; van der Ploeg, Rein; Schapendonk, Johannes; Schrier, Ernst; Duijzentkunst, Rob Smit; Spruit-van Eijk, Monica; Versteegen, Gerbrig; Voesten, Harrie

    2015-10-01

    A structured, multidisciplinary approach in the rehabilitation process after amputation is needed that includes a greater focus on the involvement of both (para)medics and prosthetists. There is considerable variation in prosthetic prescription concerning the moment of initial prosthesis fitting and the use of replacement parts. To produce an evidence-based guideline for the amputation and prosthetics of the lower extremities. This guideline provides recommendations in support of daily practice and is based on the results of scientific research and further discussions focussed on establishing good medical practice. Part 2 focuses on rehabilitation process and prosthetics. Systematic literature design. Literature search in five databases and quality assessment on the basis of evidence-based guideline development. An evidence-based multidisciplinary guideline on amputation and prosthetics of the lower extremity. The best care (in general) for patients undergoing amputation of a lower extremity is presented and discussed. This part of the guideline provides recommendations for treatment and reintegration of patients undergoing amputation of a lower extremity and can be used to provide patient information. This guideline provides recommendations in support of daily practice and is based on the results of scientific research and further discussions focussed on establishing good medical practice. © The International Society for Prosthetics and Orthotics 2014.

  1. Obtention of a prosthetic group for labelling of radioiodinated proteins

    International Nuclear Information System (INIS)

    Santos, Josefina da S.; Colturato, Maria Tereza; Araujo, Elaine B. de

    2000-01-01

    Antibodies and peptides labeled with radionuclides has been extensively used in radioimmunotherapy and radioimmunodetection. The principal problem with the use of radioiodinated proteins is the in vivo dehalogenation. The use of prosthetic groups for indirect labeling of proteins with radioiodine has showed to be useful on labeling proteins with greater in vivo stability. A procedure is described for the preparation of an radioiodinated prosthetic group (N-succinimidyl 4-radioiodine-benzoate-SIB), using procedure described by Stocklin et al, with the iodination of p-bromo-benzoic acid and subsequent reaction with TSTU. Preliminary labeling results showed that the prosthetic group can be obtained in a good yield. The coupling of the SIB to the protein will be studied using human IgG as protein model. (author)

  2. Surgical-prosthetic treatment of large mandibular cysts

    Directory of Open Access Journals (Sweden)

    Džambas Ljubiša D.

    2003-01-01

    Full Text Available This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II. After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient’s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis. The patient’s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

  3. Prosthetic mitral valve thrombosis in pregnancy: from thrombolysis to anticoagulation.

    Science.gov (United States)

    Cardoso, Gonçalo; Aguiar, Carlos; Andrade, Maria João; Patrício, Lino; Freire, Isabel; Serrano, Fátima; Anjos, Rui; Mendes, Miguel

    2015-01-01

    Pregnant women with mechanical prosthetic heart valves are at increased risk for valve thrombosis. Management decisions for this life-threatening complication are complex. Open-heart surgery has a very high risk of maternal mortality and fetal loss. Bleeding and embolic risks associated with thrombolytic agents, the limited efficacy of thrombolysis in certain subgroups, and a lack of experience in the setting of pregnancy raise important concerns. We report a case of mitral prosthetic valve thrombosis in early pregnancy, which was successfully treated with streptokinase. Ten years later, the same patient had an uneventful pregnancy, throughout which acenocoumarol was maintained. With this case we review the prevention (with oral anticoagulant therapy) and treatment of prosthetic valve thrombosis during pregnancy, which is important for both obstetrician and cardiologist. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  4. Image segmentation for enhancing symbol recognition in prosthetic vision.

    Science.gov (United States)

    Horne, Lachlan; Barnes, Nick; McCarthy, Chris; He, Xuming

    2012-01-01

    Current and near-term implantable prosthetic vision systems offer the potential to restore some visual function, but suffer from poor resolution and dynamic range of induced phosphenes. This can make it difficult for users of prosthetic vision systems to identify symbolic information (such as signs) except in controlled conditions. Using image segmentation techniques from computer vision, we show it is possible to improve the clarity of such symbolic information for users of prosthetic vision implants in uncontrolled conditions. We use image segmentation to automatically divide a natural image into regions, and using a fixation point controlled by the user, select a region to phosphenize. This technique improves the apparent contrast and clarity of symbolic information over traditional phosphenization approaches.

  5. Prosthetic abutment influences bone biomechanical behavior of immediately loaded implants

    Directory of Open Access Journals (Sweden)

    Germana de Villa CAMARGOS

    2016-01-01

    Full Text Available Abstract This study aimed to evaluate the influence of the type of prosthetic abutment associated to different implant connection on bone biomechanical behavior of immediately and delayed loaded implants. Computed tomography-based finite element models comprising a mandible with a single molar implant were created with different types of prosthetic abutment (UCLA or conical, implant connection (external hexagon, EH or internal hexagon, IH, and occlusal loading (axial or oblique, for both immediately and delayed loaded implants. Analysis of variance at 95%CI was used to evaluate the peak maximum principal stress and strain in bone after applying a 100 N occlusal load. The results showed that the type of prosthetic abutment influences bone stress/strain in only immediately loaded implants. Attachment of conical abutments to IH implants exhibited the best biomechanical behavior, with optimal distribution and dissipation of the load in peri-implant bone.

  6. Synthesis and characterization of polypyrrole grafted chitin

    Science.gov (United States)

    Ramaprasad, A. T.; Latha, D.; Rao, Vijayalakshmi

    2017-05-01

    Synthesis and characterization of chitin grafted with polypyrrole (PPy) is reported in this paper. Chitin is soaked in pyrrole solution of various concentrations for different time intervals and polymerized using ammonium peroxy disulphate (APS) as an initiator. Grafting percentage of polypyrrole onto chitin is calculated from weight of chitin before and after grafting. Grafting of polymer is further verified by dissolution studies. The grafted polymer samples are characterized by FTIR, UV-Vis absorption spectrum, XRD, DSC, TGA, AFM, SEM and conductivity studies.

  7. 77 FR 14989 - Medicare Program; Revisions to the Durable Medical Equipment, Prosthetics, Orthotics, and...

    Science.gov (United States)

    2012-03-14

    ... section 1861(s)(8) of the Act. Prosthetic devices are defined as devices (other than dental) which replace... examples of prosthetic devices include cardiac pacemakers, cochlear implants, electrical continence aids...

  8. A histomorphometric meta-analysis of sinus elevation with various grafting materials.

    Science.gov (United States)

    Handschel, Jörg; Simonowska, Melani; Naujoks, Christian; Depprich, Rita A; Ommerborn, Michelle A; Meyer, Ulrich; Kübler, Norbert R

    2009-06-11

    Several grafting materials have been used in sinus augmentation procedures including autogenous bone, demineralized freeze-dried bone (DFDBA), hydroxyapatite, beta-tricalcium phosphate (beta-TCP), anorganic deproteinized bovine bone and combination of these and others. Up to now a subject of controversy in maxillofacial surgery and dentistry is, what is the most appropriate graft material for sinus floor augmentation. The aim of this study is to provide a body of evidence-based data regarding grafting materials in external sinus floor elevation concerning the fate of the augmented material at the histomorphological level, through a meta-analysis of the available literature. The literature searches were performed using the National Library of Medicine. The search covered all English and German literature from 1995 until 2006. For analyzing the amount of bone the parameter "Total Bone Volume" (TBV) was assessed. TBV is determined as the percentage of the section consisting of bone tissue. In a relatively early phase after implantation the autogenous bone shows the highest TBV values. Interestingly, the different TBV levels approximate during the time. After 9 months no statistically significant differences can be detected between the various grafting materials. From a clinical point of view, the use of autogenous bone is advantageous if a prosthetic rehabilitation (with functional loading) is expected within 9 months. In other cases the use of anorganic deproteinized bovine bone in combination with autogenous bone seems to be preferable. Donor side morbidity is ignored in this conclusion.

  9. A histomorphometric meta-analysis of sinus elevation with various grafting materials

    Directory of Open Access Journals (Sweden)

    Handschel Jörg

    2009-06-01

    Full Text Available Abstract Several grafting materials have been used in sinus augmentation procedures including autogenous bone, demineralized freeze-dried bone (DFDBA, hydroxyapatite, β-tricalcium phosphate (β-TCP, anorganic deproteinized bovine bone and combination of these and others. Up to now a subject of controversy in maxillofacial surgery and dentistry is, what is the most appropriate graft material for sinus floor augmentation. Purpose The aim of this study is to provide a body of evidence-based data regarding grafting materials in external sinus floor elevation concerning the fate of the augmented material at the histomorphological level, through a meta-analysis of the available literature. Materials and methods The literature searches were performed using the National Library of Medicine. The search covered all English and German literature from 1995 until 2006. For analyzing the amount of bone the parameter "Total Bone Volume" (TBV was assessed. TBV is determined as the percentage of the section consisting of bone tissue. Results In a relatively early phase after implantation the autogenous bone shows the highest TBV values. Interestingly, the different TBV levels approximate during the time. After 9 months no statistically significant differences can be detected between the various grafting materials. Conclusion From a clinical point of view, the use of autogenous bone is advantageous if a prosthetic rehabilitation (with functional loading is expected within 9 months. In other cases the use of anorganic deproteinized bovine bone in combination with autogenous bone seems to be preferable. Donor side morbidity is ignored in this conclusion.

  10. Development of EPDM based thermoplastic elastomers for oil resistant applications: optimization of radiation grafting parameters

    International Nuclear Information System (INIS)

    Chaudhari, C.V.; Dubey, K.A.; Bhardwaj, Y.K.; Sabharwal, S.

    2008-01-01

    Full text: Ethylene-propylene diene terpolymer (EPDM) is currently among the most industrially useful elastomers because of its certain unique properties like excellent heat resistance, resistance towards ozone deterioration, high impact strength. However EPDM has a serious drawback of weak adhesion properties and tendency to swell in contact with paraffin oil and aromatic hydrocarbons. Blending EPDM with suitable polar elastomers or grafting polar polymer chains onto EPDM is an easy method to overcome this drawback. Radiation grafting of Acrylonitrile (ACN) on EPDM provides an easy and effective method of incorporating ACN uniformly on the EPDM backbone. Grafting of ACN on EPDM is expected to result grafted copolymer with better oil resistance, hardness and better compatibility with polar polymer matrices. In the present study radiation induced grafting of ACN onto EPDM rubber film was investigated by mutual radiation grafting technique. Effect of experimental variables viz. radiation dose, dose rate, types of solvents and monomer content on extent of grafting was studied. The solvent composition of Acetone:CCl 4 (20:80) was found to be the optimum mixture which resulted in highest degree of grafting. It was found that the degree of grafting increases with radiation dose, monomer content and decreases with dose rate

  11. Maxillofacial prosthetics training and practice profiles in the United States.

    Science.gov (United States)

    Sheets, James L; Yuan, Judy Chia-Chun; Sukotjo, Cortino; Davis, Betsy K; Wee, Alvin G

    2017-10-01

    The motivation of maxillofacial prosthodontists to go into fellowship training and specific procedures in maxillofacial prosthetics practice once they have completed training has not been previously evaluated. The purpose of this study was to survey maxillofacial prosthodontists in the United States to investigate their reasons for pursuing maxillofacial prosthetic training and their practice profiles. In June 2015, a survey was sent to all US maxillofacial prosthodontists asking for descriptive demographics, their reasoning as to what prompted entrance into a maxillofacial prosthetic program, and their practice pattern. Frequencies, percentages, means, and standard deviations were calculated and reported. The survey response rate was 60.4%. The main reason for pursuing maxillofacial training was primarily personal satisfaction, prosthodontic residency exposure, and mentorship rather than media exposure and compensation. The time spent in prosthodontic practice varied among practitioners, with the majority of practice time spent accomplishing standard prosthodontic procedures (65.59%) versus maxillofacial (25.53%) or surgical procedures (9.67%). Of 12 clinical maxillofacial procedures inquired about, the most prevalent were obturators, dental oncology, and mandibular resections. This study reveals that personal satisfaction, mentorship, and prosthodontic residency exposure were the reasons most prosthodontists pursued an additional year of maxillofacial prosthetic fellowship. Most were very satisfied with their training and chosen career path and would recommend an additional year of training. The majority of maxillofacial prosthodontists provided maxillofacial prosthetic treatment for approximately one fourth of their practice time. The most common procedures performed were obturators, dental oncology, and mandibular resections. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Prosthetic Mesh Repair for Incarcerated Inguinal Hernia

    Directory of Open Access Journals (Sweden)

    Cihad Tatar

    2016-08-01

    Full Text Available Background: Incarcerated inguinal hernia is a commonly encountered urgent surgical condition, and tension-free repair is a well-established method for the treatment of noncomplicated cases. However, due to the risk of prosthetic material-related infections, the use of mesh in the repair of strangulated or incarcerated hernia has often been subject to debate. Recent studies have demonstrated that biomaterials represent suitable materials for performing urgent hernia repair. Certain studies recommend mesh repair only for cases where no bowel resection is required; other studies, however, recommend mesh repair for patients requiring bowel resection as well. Aim: The aim of this study was to compare the outcomes of different surgical techniques performed for strangulated hernia, and to evaluate the effect of mesh use on postoperative complications. Study Design: Retrospective cross-sectional study. Methods: This retrospective study was performed with 151 patients who had been admitted to our hospital’s emergency department to undergo surgery for a diagnosis of incarcerated inguinal hernia. The patients were divided into two groups based on the applied surgical technique. Group 1 consisted of 112 patients treated with mesh-based repair techniques, while Group 2 consisted of 39 patients treated with tissue repair techniques. Patients in Group 1 were further divided into two sub-groups: one consisting of patients undergoing bowel resection (Group 3, and the other consisting of patients not undergoing bowel resection (Group 4. Results: In Group 1, it was observed that eight (7.14% of the patients had wound infections, while two (1.78% had hematomas, four (3.57% had seromas, and one (0.89% had relapse. In Group 2, one (2.56% of the patients had a wound infection, while three (7.69% had hematomas, one (2.56% had seroma, and none had relapses. There were no statistically significant differences between the two groups with respect to wound infection

  13. Bone Grafting: Sourcing, Timing, Strategies, and Alternatives.

    Science.gov (United States)

    Egol, Kenneth A; Nauth, Aaron; Lee, Mark; Pape, Hans-Christoph; Watson, J Tracy; Borrelli, Joseph

    2015-12-01

    Acute fractures, nonunions, and nonunions with bone defects or osteomyelitis often need bone graft to facilitate union. There are several factors to consider when it is determined that a bone graft is needed. These factors include the source of the bone graft (autograft vs. allograft), proper timing for placement of the bone graft, strategies to avoid further complications (particularly in the setting of osteomyelitis), and with the development of a variety of bone graft substitutes, whether alternatives to autograft are available and appropriate for the task at hand. Autograft bone has commonly been referred to as the "gold standard" of bone grafts, against which the efficacy of other grafts has been measured. The best timing for when to place a bone graft or substitute is also somewhat controversial, particularly after an open fracture or a potentially contaminated bed. The treatment of infected nonunions, particularly those that require a graft to facilitate healing, can be quite challenging. Typically, the infection is completely eradicated before placement of a bone graft, but achieving a sterile bed and the timing of a bone graft require strategic thinking and planning. This review outlines the benefits of autografts, the most suitable sites for harvesting bone grafts, the timing of bone graft procedures, the potential risks and benefits of grafting in the face of infection, and the currently available bone graft extenders.

  14. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    Science.gov (United States)

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  15. Costal Grafting in Mandibular Reconstruction.

    Science.gov (United States)

    Bachelet, Jean-Thomas; Bourlet, Jerôme; Château, Joseph; Jacquemart, Mathieu; Dufour, Clémence; Mojallal, Ali; Gleizal, Arnaud

    2015-11-01

    Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery, and free fibular flap is the gold standard for this indication. However, there are alternatives; nonvascular bone grafting is one of them, and we present the costal grafting for mandibular reconstruction, a classic technique that is reliable, efficient, and produced less morbidity than the technique of using composite free flaps. A 9-year retrospective review of 54 patients treated surgically for mandibular reconstruction was performed. The criterion mainly analyzed was graft survival. The surgical technique was described in detail. A total of 54 patients with mandibular bone defect were identified. Five symphysis, 46 corpus, and 20 ramus defects were considered. These patients underwent reconstruction by costal grafting, and the engrafting was successful in 92.6% of cases. Dental rehabilitation with dental implants was realized in 70% of cases. The approach described in this article allowed the authors to obtain good results with costal grafting for mandibular reconstruction and dental rehabilitation. Costal grafting is a good alternative for fibula free flap in specific indications. Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery. Since the 1980s, the gold standard for these defects is the use of free fibular flap.(1) In some cases, this technique is contradicted; the surgeon then has several possibilities for the use of free osteomyocutaneous flaps (iliac crest, scapula, and serrato-costal flaps).(2-8).

  16. Effects of bone grafting, performed with corticotomies and buccal tooth movements, on dehiscence formation in dogs.

    Science.gov (United States)

    Bare-Welchel, Britney; Campbell, Phillip M; Gonzalez, Marianela; Buschang, Peter H

    2017-06-01

    A randomized split-mouth experiment was performed in dogs to determine the effects of bone grafting, together with corticotomies and buccal tooth movements, on dehiscence formation. Bilateral full-thickness mucoperiosteal buccal flaps were raised, and corticotomies were performed with a piezosurgery unit adjacent to the maxillary second premolars in 7 dogs. The experimental (graft+) side received a demineralized freeze-dried allograph and a resorbable collagen membrane. The second premolars were expanded with archwires for 9 weeks, followed by 3 weeks of consolidation. Soft tissue measurements included probing depths, attachment loss, and recession. Tooth movements were monitored using intraoral, radiographic, and model measurements. Bone surrounding the second premolars was evaluated with microcomputed tomography. New bone formation was analyzed histologically using calcein and alizarin fluorescent labels, and hematoxylin and eosin stains. Postsurgical healing progressed normally with no signs of infection. The graft+ and control (graft-) second premolars underwent similar amounts of expansion (about 2.5 mm intraorally; about 1.7 mm radiographically) and tipping, with no statistically significant side differences. The soft tissue periodontium was not affected on either side. There were bony dehiscences on both the graft+ and graft- sides, with slightly but significantly (P = 0.038) more bone loss over the mesial root on the graft- side. Bone material density was significantly (P = 0.028) greater on the graft+ side. Buccal bone apposition was evident surrounding graft particles, and mineralized particulate graft material was present at the apical aspect of the roots on the graft+ side. Bone grafting does not prevent dehiscence formation because only a limited amount of new bone is formed, primarily at the more apical aspects of the tooth's roots. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  17. Non- invasive in vivo analysis of a murine aortic graft using high resolution ultrasound microimaging

    International Nuclear Information System (INIS)

    Rowinska, Zuzanna; Zander, Simone; Zernecke, Alma; Jacobs, Michael; Langer, Stephan; Weber, Christian; Merx, Marc W.; Koeppel, Thomas A.

    2012-01-01

    Introduction: As yet, murine aortic grafts have merely been monitored histopathologically. The aim of our study was to examine how these grafts can be monitored in vivo and non-invasively by using high-resolution ultrasound microimaging to evaluate function and morphology. A further aim was to prove if this in vivo monitoring can be correlated to immunohistological data that indicates graft integrity. Methods: Murine infrarenal aortic isografts were orthotopically transplanted into 14 female mice (C57BL/6-Background) whereas a group of sham-operated animals (n = 10) served as controls. To assess the graft morphology and hemodynamics, we examined the mice over a post-operative period of 8 weeks with a sophisticated ultrasound system (Vevo 770, Visual Sonics). Results: The non-invasive graft monitoring was feasible in all transplanted mice. We could demonstrate a regular post-transplant graft function and morphology, such as anterior/posterior wall displacement and wall thickness. Mild alterations of anterior wall motion dynamics could only be observed at the site of distal graft anastomosis (8 weeks after grafting (transplant vs. sham mice: 0.02 mm ± 0.01 vs. 0.03 mm ± 0.01, p < 0.05). However, the integrity of the entire graft wall could be confirmed by histopathological evaluation of the grafts. Conclusions: With regard to graft patency, function and morphology, high resolution ultrasound microimaging has proven to be a valuable tool for longitudinal, non-invasive, in vivo graft monitoring in this murine aortic transplantation model. Consequently, this experimental animal model provides an excellent basis for molecular and pharmacological studies using genetically engineered mice.

  18. ALL-CERAMIC APPLIANCES FOR PROSTHETIC REHABILITATION IN YOUNG PATIENTS

    Directory of Open Access Journals (Sweden)

    Alexandru BASNO

    2016-03-01

    Full Text Available The aim of the present study was to assess a possible fixed rehabilitation in young patients, by means of CAD-CAM techniques. Materials and method. The CERCON substractive technique with zirconium oxide blanks was applied. Discussion. The obtained prosthetic structures are characterized by a better aesthetic integration, optimum marginal adaptation and suitable clinical longevity. Conclusions. All-ceramic prostheses appear as a biological solution in the prosthetic rehabilitation of young patients, as they require reduced removal of both enamel and dentin, while obeying the biological conservative principle of treatment.

  19. Prosthetic limbs on display: from maker to user

    Directory of Open Access Journals (Sweden)

    Sophie Goggins

    2017-11-01

    Full Text Available Prosthetic devices have been used in museums to tell clinical, technical and personal stories. Here we reflect on the ways artificial limbs and their users were represented in recent museum projects at the Royal College of Surgeons of England and at National Museums Scotland. We consider how these meaningful artefacts illuminate three overlapping themes in museum scholarship and practice: the representation of disabled people and disability in museums; reflections on conflict-acquired limb loss; and the presence or otherwise of user or patient voice in interpretation. In working with and representing people who design and wear prosthetics we advocate a balance between narratives of technique and of use.

  20. Case Study and Review: Treatment of Tricuspid Prosthetic Valve Thrombosis

    Science.gov (United States)

    Yi Zhang, David; Lozier, Jay; Chang, Richard; Sachdev, Vandana; Chen, Marcus Y.; Audibert, Jennifer L.; Horvath, Keith A.; Rosing, Douglas R.

    2011-01-01

    Prosthetic valve thrombosis (PVT) is a severe and life-threatening complication of heart valve replacement. Conventional therapy is surgical thrombectomy or valve replacement. Medical thrombolysis is another emerging option. We report the case of a 57 year old woman with a history of Ebstein anomaly who underwent successful treatment of a tricuspid prosthetic valve thrombosis with intra-atrial infusion of very low dose recombinant tissue plasminogen activator (tPA). We review the presentation, etiology, diagnosis, and treatment of the tricuspid PVT emphasizing a modified medical option as a safe, minimally invasive alternative to surgical intervention or conventional medical therapy for tricuspid valve thrombosis. PMID:22000268

  1. Reconstruction of the maxilla following hemimaxillectomy defects with scapular tip grafts and dental implants.

    Science.gov (United States)

    Mertens, Christian; Freudlsperger, Christian; Bodem, Jens; Engel, Michael; Hoffmann, Jürgen; Freier, Kolja

    2016-11-01

    Treatment of post-resective defects of the maxilla can be challenging and usually requires dental obturation or microvascular reconstruction. As compared to soft-tissue microvascular grafts, bone reconstruction can additionally allow for facial support and retention of dental implants. The aim of this study was to evaluate scapular tip grafts with respect to their applicability for maxillary reconstruction and their potential to retain dental implants for later dental rehabilitation. In this retrospective study, 14 patients with hemimaxillectomy defects were reconstructed with free scapular tip grafts, oriented horizontally, to rebuild the palate and alveolar ridge. After bone healing, three-dimensional virtual implant planning was performed, and a radiographic guide was fabricated to enable implant placement in the optimal anatomic and prosthetic position. All patients' mastication and speech were evaluated, along with the extent of defect closure, suitability of the graft sites for implant placement, and soft-tissue stability. Pre- and postsurgical radiographs were also evaluated. A good postoperative outcome was achieved in all patients, with complete closure of maxillary defects that were class II, according to the system of Brown and Shaw. Additional bone augmentation was necessary in two patients in order to increase vertical bone height. Patients were subsequently treated with 50 dental implants to retain dental prostheses. In all cases, additional soft-tissue surgery was necessary to achieve a long-term stable periimplant situation. No implants were lost during the mean observation period of 34 months. Due to its specific form, the scapular tip graft is well suited to reconstruct the palate and maxillary alveolar ridge and to enable subsequent implant-retained rehabilitation. Due to the limited bone volume, an accurate three-dimensional graft orientation is essential. Furthermore, most cases require additional soft-tissue surgery to achieve a long

  2. Primary graft dysfunction.

    Science.gov (United States)

    Suzuki, Yoshikazu; Cantu, Edward; Christie, Jason D

    2013-06-01

    Primary graft dysfunction (PGD) is a syndrome encompassing a spectrum of mild to severe lung injury that occurs within the first 72 hours after lung transplantation. PGD is characterized by pulmonary edema with diffuse alveolar damage that manifests clinically as progressive hypoxemia with radiographic pulmonary infiltrates. In recent years, new knowledge has been generated on risks and mechanisms of PGD. Following ischemia and reperfusion, inflammatory and immunological injury-repair responses appear to be key controlling mechanisms. In addition, PGD has a significant impact on short- and long-term outcomes; therefore, the choice of donor organ is impacted by this potential adverse consequence. Improved methods of reducing PGD risk and efforts to safely expand the pool are being developed. Ex vivo lung perfusion is a strategy that may improve risk assessment and become a promising platform to implement treatment interventions to prevent PGD. This review details recent updates in the epidemiology, pathophysiology, molecular and genetic biomarkers, and state-of-the-art technical developments affecting PGD. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. A meta-analysis to compare Dacron versus polytetrafluroethylene grafts for above-knee femoropopliteal artery bypass.

    Science.gov (United States)

    Rychlik, Igor J; Davey, Philip; Murphy, Jamie; O'Donnell, Mark E

    2014-08-01

    Surgical revascularization for lower limb ischemia remains an important component for optimization of quality of life and symptoms in patients with peripheral arterial disease. In the absence of a vein graft, prosthetic alternatives are considered. The objective of this meta-analysis was to establish which prosthetic graft, Dacron or polytetrafluroethylene (PTFE), has the better long-term patency in patients undergoing an above-knee femoropopliteal arterial bypass. This meta-analysis was performed by use of Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search of all relevant databases was performed from 1990 to 2013 with the Medical Subject Headings "Dacron," "polytetrafluroethylene," "PTFE," "above knee," "femoropopliteal," and "bypass" combined with the Boolean operator "AND." The inclusion criteria were randomized controlled trials, use of Dacron vs PTFE prosthetic conduits, and completion of an above-knee femoropopliteal arterial bypass involving adult patients older than 18 years presenting with disabling claudication, rest pain or tissue loss, occlusion of the superficial femoral artery, and reconstitution of the above-knee popliteal artery. Whenever studies included above- and below-knee data, only the above-knee arterial bypass data were extracted and analyzed. Graft patency rates were calculated with RevMan 5.1 software provided by the Cochrane Collaboration. Ninety-one publications were reviewed. After exclusion of duplicate, nonrandomized, and alternative bypass surgery studies, eight randomized controlled trials were identified and included in the meta-analysis. Two of the included trials represented follow-up evaluation of two previous studies, and for the purpose of this analysis, the initial and follow-up studies were subsequently evaluated as one trial. In this meta-analysis, 1192 patients were assessed, including 601 Dacron and 591 PTFE above-knee lower limb arterial bypasses. Primary

  4. Study of radiation induced grafting of [(methacryloylamino)-propyl] trimethyl ammonium chlorite (MPTAC) on to cotton fabrics and its application

    International Nuclear Information System (INIS)

    Selambakkannu, S.

    2014-01-01

    Quaternary ammonium salt, [(methacryloylamino)-propyl] trimethyl ammonium chlorite (MPTAC) had been used as monomer in mutual radiation grafting process on cotton fabrics with the aid of high energy gamma radiation source. The polymer chains of MPTAC were successfully grafted covalently onto cotton fabrics. Effect of selected experimental variables such as irradiation dose, monomer concentration, and ambient conditions and effect of inhibitors on extent of grafting had been analyzed. Grafting yield increases steadily with monomer concentration. The highest grafting yield obtained at 2 kGy and reduces thereafter then become almost constant at higher dose range. The grafted samples characterized for its surface morphology. Finally the grafted cotton subjected to its dye uptake capacity and antibacterial efficacy. The grafted cotton fiber was used in absorption studies of aqueous basic dye solution, namely AB74. The grafted cotton posses very good dye uptake capacity. The maximum dye uptake capacity of the grafted cotton sample was 150 mg/g. Antibacterial efficacy has been tested by qualitative and quantitative methods against model bacteria S. aureus and E. coli from gram positive and gram negative respectively. 20 % grafted cotton was found to be responsible of 2 log cycle reductions for the E.coli and S.aureus colonies. (author)

  5. 76 FR 64429 - Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting

    Science.gov (United States)

    2011-10-18

    ... AFFAIRS Advisory Committee on Prosthetics and Special-Disabilities Programs; Notice of Meeting The...) ] that a meeting of the Advisory Committee on Prosthetics and Special- Disabilities Programs will be held... advise the Secretary of Veterans Affairs on VA's prosthetics programs designed to provide state-of-the...

  6. 78 FR 35099 - Proposed Information Collection Activity: [Claim, Authorization and Invoice for Prosthetic Items...

    Science.gov (United States)

    2013-06-11

    ... AFFAIRS Proposed Information Collection Activity: [Claim, Authorization and Invoice for Prosthetic Items... information needed to determine eligibility and authorize funding for various prosthetic services. DATES..., VA Form 10- 1394. (d) Prosthetic Authorization for Items or Services, VA Form 10- 2421. (e...

  7. 75 FR 45206 - Proposed Information Collection (Claim, Authorization and Invoice for Prosthetic Items and...

    Science.gov (United States)

    2010-08-02

    ... AFFAIRS Proposed Information Collection (Claim, Authorization and Invoice for Prosthetic Items and... information needed to determine eligibility and authorize funding for various prosthetic services. DATES... Adaptive Equipment Motor Vehicle, VA Form 10- 1394. c. Prosthetic Authorization for Items or Services, VA...

  8. 75 FR 62185 - Proposed Information Collection (Claim, Authorization and Invoice for Prosthetic Items and...

    Science.gov (United States)

    2010-10-07

    ... AFFAIRS Proposed Information Collection (Claim, Authorization and Invoice for Prosthetic Items and...-0103. c. Application for Adaptive Equipment Motor Vehicle, VA Form 10- 1394. d. Prosthetic Authorization for Items or Services, VA Form 10-2421. e. Prosthetic Service Card Invoice, VA Form 10-2520. f...

  9. Evaluation of a xenogeneic acellular collagen matrix as a small-diameter vascular graft in dogs--preliminary observations.

    Science.gov (United States)

    Nemcova, S; Noel, A A; Jost, C J; Gloviczki, P; Miller, V M; Brockbank, K G

    2001-01-01

    Autogenous veins are the materials of choice for arterial reconstruction. In the absence of autogenous material, prosthetic materials are used. However, vascular prostheses of less than 0.4 cm in diameter have low long-term patency. This study was designed to determine if cells would infiltrate an engineered xenogeneic biomaterial used as a small diameter arterial graft in dogs and, if so, to determine the phenotype of the infiltrating cells. Nine acellular xenogeneic grafts (0.4 cm in diameter, 5 cm long), composed of porcine collagen derived from the submucosa of the small intestine and type I bovine collagen, were implanted as end to-end interposition grafts in femoral arteries of five male mongrel dogs (total of nine grafts). All dogs received daily aspirin (325 mg). Patency of implanted grafts was monitored weekly by Duplex ultrasonography. After 9 weeks, or earlier in case of blood flow reduction by at least 75%, grafts were explanted and prepared for light or electron microscopy to evaluate cellularization. Eight of nine grafts remained patent up to 9 weeks. At explant, diameters were 0.31 +/- 0.02 cm at the midgraft, and 0.14 +/- 0.01 and 0.19 +/- 0.01 cm at the proximal and distal anastomoses. At explant, cells of mesenchymal origin (endothelial cells, smooth muscle cells, myofibroblasts) were embedded in the extracellular matrix of the graft scaffold. Minimal evidence of cellular inflammatory reaction and no aneurysmal dilatation or thrombus formation was detected. Variable degrees of hyperplasia were present at proximal and distal anastomoses. This preliminary study demonstrates that a collagen-based xenogeneic biomaterial provides a scaffold for cellularization when used for arterial reconstruction in dogs.

  10. Pre-prosthetic surgical alterations in maxillectomy to enhance the prosthetic prognoses as part of rehabilitation of oral cancer patient.

    Science.gov (United States)

    El Fattah, H; Zaghloul, A; Pedemonte, E; Escuin, T

    2012-03-01

    After maxillectomy, prosthetic restoration of the resulting defect is an essential step because it signals the beginning of patient's rehabilitation. The obturator used to restore the defect should be comfortable, restore adequate speech, deglutition, mastication, and be cosmetically acceptable, success will depend on the size and location of the defect and the quantity and integrity of the remaining structures, in addition to pre-prosthetic surgical preparation of defect site. Preoperative cooperation between the oncologist surgeon and the maxillofacial surgeon may allow obturation of a resultant defect by preservation of the premaxilla or the tuberosity on the defect side and maintaining the alveolar bone or teeth adjacent to the defect. This study evaluates the importance of pre-prosthetic surgical alterations at the time maxillectomy on the enhancement of the prosthetic prognoses as part of the rehabilitation of oral cancer patient. The study was carried out between 2003- 2008, on 66 cancer patients(41 male-25 female) age ranged from 33 to 72 years, at National Cancer Institute, Cairo University, whom underwent maxillectomy surgery to remove malignant tumor as a part of cancer treatment. Patients were divided in two groups. Group A: Resection of maxilla followed by preprosthetic surgical preparation. Twenty-four cancer patients (13 male - 11 female). Group B: Resection of maxilla without any preprosthetic surgical preparation. Forty-two cancer patients (28 male-14 female). Outcome variables measured included facial contour and aesthetic results, speech understandability, ability to eat solid foods, oronasal separation, socializing outside the home, and return-to-work status. Flap success and donor site morbidity were also studied. To improve the prosthetic restoration of maxillary defect resulting maxillary resection as part treatment of maxillofacial tumor depends on the close cooperation between prosthodontist and surgeon, by combination of pre-prosthetic

  11. Radiation grafting on natural films

    International Nuclear Information System (INIS)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37–40 N mm −1 ) and puncture deformation (PD=6.5–9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282–296 N mm −1 and PD of 5.0–5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films. - Highlights: • Irradiation of zein

  12. Computed tomography evaluation of autogenous graft in sinus lift surgery; Analise por tomografia computadorizada do enxerto autogeno na cirurgia de 'sinus lift'

    Energy Technology Data Exchange (ETDEWEB)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Tecnica Operatoria e Cirurgia Experimental; Alves, Maria Teresa de Seixas [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Anatomia Patologica

    2001-02-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  13. Clinical and histologic outcomes of socket grafting after flapless tooth extraction: a systematic review of randomized controlled clinical trials.

    Science.gov (United States)

    Jambhekar, Shantanu; Kernen, Florian; Bidra, Avinash S

    2015-05-01

    allografts (0.58 mm), followed by alloplasts (0.77 mm) and sockets without any grafting (1.74 mm). The mean histologic outcomes at or beyond the 12-week reentry period revealed the highest vital bone content for sockets grafted with alloplasts (45.53%), followed by sockets with no graft material (41.07%), xenografts (35.72%), and allografts (29.93%). The amount of remnant graft material was highest for sockets grafted with allografts (21.75%), followed by xenografts (19.3%) and alloplasts (13.67%). The highest connective tissue content at the time of reentry was seen for sockets with no grafting (52.53%), followed by allografts (51.03%), xenografts (44.42%), and alloplast (38.39%). Data for new and emerging biomaterials such as cell therapy and tissue regenerative materials were not amenable to calculations because of biomaterial heterogeneity and small sample sizes. After flapless extraction of teeth, and using a minimum healing period of 12 weeks as a temporal measure, xenografts and allografts resulted in the least loss of socket dimensions compared to alloplasts or sockets with no grafting. Histologic outcomes after a minimum of 12 weeks of healing showed that sockets grafted with alloplasts had the maximum amount of vital bone and the least amount of remnant graft material and remnant connective tissue. There is a limited but emerging body of evidence for the predictable regeneration of deficient buccal bone with socket grafting materials, need for barrier membranes, use of tissue engineering, and use of autogenous soft tissue grafts from the palate to cover the socket. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. Histological evaluation of the influence of magnetic field application in autogenous bone grafts in rats

    Directory of Open Access Journals (Sweden)

    Ponzoni Deise

    2009-01-01

    Full Text Available Abstract Background Bone grafts are widely used in oral and maxillofacial reconstruction. The influence of electromagnetic fields and magnets on the endogenous stimulation of target tissues has been investigated. This work aimed to assess the quality of bone healing in surgical cavities filled with autogenous bone grafts, under the influence of a permanent magnetic field produced by in vivo buried devices. Methods Metal devices consisting of commercially pure martensitic stainless steel washers and titanium screws were employed. Thirty male Wistar rats were divided into 3 experimental and 3 control groups. A surgical bone cavity was produced on the right femur, and a bone graft was collected and placed in each hole. Two metallic washers, magnetized in the experimental group but not in the control group, were attached on the borders of the cavity. Results The animals were sacrificed on postoperative days 15, 45 and 60. The histological analysis of control and experimental samples showed adequate integration of the bone grafts, with intense bone neoformation. On days 45 and 60, a continued influence of the magnetic field on the surgical cavity and on the bone graft was observed in samples from the experimental group. Conclusion The results showed intense bone neoformation in the experimental group as compared to control animals. The intense extra-cortical bone neoformation observed suggests that the osteoconductor condition of the graft may be more susceptible to stimulation, when submitted to a magnetic field.

  15. The Design And Development Of Adjustable Prosthetic Device For A ...

    African Journals Online (AJOL)

    Using a six bar link knee mechanism an artificial adjustable leg is produced for an amputee. The prosthetic device when fitted to an amputee provided easy movement for the left leg amputee. It is produced using readily available materials involving aluminum, steel, polyethylene, leader, glue etc. the device has a special ...

  16. American Board for Certification in Orthotics and Prosthetics

    Science.gov (United States)

    ... enable scripts and reload this page. My ABC ABC Directory State Licensure Professional Ethics News & Events OandPCare.org Contact Us It looks like ... Practitioner Career Opportunities Professional & Educational Resources ... of Use Privacy Policy Contact Us News & Events American Board for Certification in Orthotics, Prosthetics & ...

  17. Predictors of Success on the Prosthetics Certification Examination

    Science.gov (United States)

    Miro, Rebecca Maria

    2014-01-01

    Students who graduate from a practitioner program in prosthetics & orthotics must achieve certification in order to obtain licensure and practice independently in 16 states. In states where licensure is not mandatory, graduates may choose to pursue certification in order assure patients that they are practicing at the highest level as well as…

  18. Early prosthetic valve endocarditis caused by Corynebacterium kroppenstedtii.

    Science.gov (United States)

    Hagemann, Jürgen Benjamin; Essig, Andreas; Herrmann, Manuel; Liebold, Andreas; Quader, Mohamed Abo

    2015-12-01

    Corynebacterium (C.) kroppenstedtii is a rarely detected agent of bacterial infections in humans. Here, we describe the first case of prosthetic valve endocarditis caused by C. kroppenstedtii. Application of molecular methods using surgically excised valve tissue was a cornerstone for the establishment of the microbiological diagnosis, which is crucial for targeted antimicrobial treatment. Copyright © 2015 Elsevier GmbH. All rights reserved.

  19. Consumer satisfaction with the services of prosthetics and orthotics facilities

    NARCIS (Netherlands)

    Bosmans, Joline; Geertzen, Jan; Dijkstra, Pieter U.

    2009-01-01

    Consumer satisfaction with the services provided in a prosthetics and orthotics (PO) facility has seldom been studied. The aim of this study was to analyze consumer satisfaction regarding the services provided by 15 PO facilities in The Netherlands. Consumers (n=1,364) of these PO facilities who

  20. Development of a 3D-Printed Robotic Prosthetic Arm

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Martinez, M.; Garcia-Miquel, A.; Vidal Martinez, N.

    2016-07-01

    Current prostheses are not affordable to the general public. 3D printing technology may allow low-cost production of such devices, making them more readily accessible to people in need. This contribution presents the set-up and the considerations that have to be taken into account to develop a functional artificial upper limb prototype. The robotic prosthetic arm reported herein was produced entirely using 3D printing technology to demonstrate its feasibility on a limited budget. The project was developed to integrate two different functional modes: a prosthetic application and a remote application. The prosthetic application is intended to emulate existing prosthetic devices using myoelectric sensors. The remote application is conceived as a tool for prevention, by providing the general public with a device that could carry out activities that entail a risk of severe physical injury. This is achieved using a hand-tracking system that allows the robotic arm to copy the user’s movements remotely and in real time. The outcome of the validation tests has been considerably successful for both applications and the total costs are on target. (Author)

  1. Diagnostic flowcharts in osteomyelitis, spondylodiscitis and prosthetic joint infection

    NARCIS (Netherlands)

    Jutte, P.; Lazzeri, E.; Sconfienza, L. M.; Cassar-Pullicino, V.; Trampuz, A.; Petrosillo, N.; Signore, A.

    Infections of the bone, spine and prosthetic joints are serious and complex conditions to diagnose and to treat. Structured diagnostic workup may very well improve the accuracy and speed of diagnosis, thereby improving the outcome since treatment may very well be more successful and less harmful if

  2. Rehabilitation regimes based upon psychophysical studies of prosthetic vision

    Science.gov (United States)

    Chen, S. C.; Suaning, G. J.; Morley, J. W.; Lovell, N. H.

    2009-06-01

    Human trials of prototype visual prostheses have successfully elicited visual percepts (phosphenes) in the visual field of implant recipients blinded through retinitis pigmentosa and age-related macular degeneration. Researchers are progressing rapidly towards a device that utilizes individual phosphenes as the elementary building blocks to compose a visual scene. This form of prosthetic vision is expected, in the near term, to have low resolution, large inter-phosphene gaps, distorted spatial distribution of phosphenes, restricted field of view, an eccentrically located phosphene field and limited number of expressible luminance levels. In order to fully realize the potential of these devices, there needs to be a training and rehabilitation program which aims to assist the prosthesis recipients to understand what they are seeing, and also to adapt their viewing habits to optimize the performance of the device. Based on the literature of psychophysical studies in simulated and real prosthetic vision, this paper proposes a comprehensive, theoretical training regime for a prosthesis recipient: visual search, visual acuity, reading, face/object recognition, hand-eye coordination and navigation. The aim of these tasks is to train the recipients to conduct visual scanning, eccentric viewing and reading, discerning low-contrast visual information, and coordinating bodily actions for visual-guided tasks under prosthetic vision. These skills have been identified as playing an important role in making prosthetic vision functional for the daily activities of their recipients.

  3. Esthetics with prosthetics in case of maxillary canine transposition: A ...

    African Journals Online (AJOL)

    Esthetics with prosthetics in case of maxillary canine transposition: A clinical report. ... provides a helpful Frequently Asked Questions about PDFs. Alternatively, you can download the PDF file directly to your computer, from where it can be opened using a PDF reader. To download the PDF, click the Download link above.

  4. 21 CFR 890.3420 - External limb prosthetic component.

    Science.gov (United States)

    2010-04-01

    ... total prosthesis. Examples of external limb prosthetic components include the following: Ankle, foot, hip, knee, and socket components; mechanical or powered hand, hook, wrist unit, elbow joint, and shoulder joint components; and cable and prosthesis suction valves. (b) Classification. Class I (general...

  5. Principles of obstacle avoidance with a transfemoral prosthetic limb.

    Science.gov (United States)

    van Keeken, Helco G; Vrieling, Aline H; Hof, At L; Postema, Klaas; Otten, Bert

    2012-10-01

    In this study, conditions that enable a prosthetic knee flexion strategy in transfemoral amputee subjects during obstacle avoidance were investigated. This study explored the hip torque principle and the static ground principle as object avoidance strategies. A prosthetic limb simulator device was used to study the influence of applied hip torques and static ground friction on the prosthetic foot trajectory. Inverse dynamics were used to calculate the energy produced by the hip joint. A two-dimensional forward dynamics model was used to investigate the relation between obstacle-foot distance and the necessary hip torques utilized during obstacle avoidance. The study showed that a prosthetic knee flexion strategy was facilitated by the use of ground friction and by larger active hip torques. This strategy required more energy produced by the hip compared to a knee extension strategy. We conclude that when an amputee maintains enough distance between the distal tip of the foot and the obstacle during stance, he or she produces sufficiently high, yet feasible, hip torques and uses static ground friction, the amputee satisfies the conditions for enable stepping over an obstacle using a knee flexion strategy. Copyright © 2011 IPEM. Published by Elsevier Ltd. All rights reserved.

  6. Effect of Modifying Prosthetic Socket Base Materials by Adding Nanodiamonds

    Directory of Open Access Journals (Sweden)

    Lifang Ma

    2015-01-01

    Full Text Available The curing process of prosthetic socket base materials requires attention owing to a series of associated problems that are yet to be addressed and solved. However, to date, few relevant studies have been reported. In this paper, nanodiamonds modified with a silane coupling agent were dispersed into a prosthetic socket base material, and the performance of the modified base materials was investigated. Adding a predetermined amount of nanodiamonds to the prosthetic socket base material increased the glass transition temperature, improved the mechanical properties of the cured base material, and reduced the influence of the volatile gas formed during the curing process on the environment. With increasing nanodiamond contents, the glass transition temperature increased and the mechanical properties improved slightly. Owing to the high thermal conductivity of the nanodiamonds, the localized heat, as a result of the curing process, could be dissipated and released. Thus, adding nanodiamonds led to a more uniform temperature field forming in the curing system. This improved the curing process and reduced the formation of volatile monomers, thereby decreasing the adverse impact of the generated volatile gases on the environment. All of these provide a potential strategy for modifying prosthetic socket base materials.

  7. Development of a prototype over-actuated biomimetic prosthetic hand.

    Directory of Open Access Journals (Sweden)

    Matthew R Williams

    Full Text Available The loss of a hand can greatly affect quality of life. A prosthetic device that can mimic normal hand function is very important to physical and mental recuperation after hand amputation, but the currently available prosthetics do not fully meet the needs of the amputee community. Most prosthetic hands are not dexterous enough to grasp a variety of shaped objects, and those that are tend to be heavy, leading to discomfort while wearing the device. In order to attempt to better simulate human hand function, a dexterous hand was developed that uses an over-actuated mechanism to form grasp shape using intrinsic joint mounted motors in addition to a finger tendon to produce large flexion force for a tight grip. This novel actuation method allows the hand to use small actuators for grip shape formation, and the tendon to produce high grip strength. The hand was capable of producing fingertip flexion force suitable for most activities of daily living. In addition, it was able to produce a range of grasp shapes with natural, independent finger motion, and appearance similar to that of a human hand. The hand also had a mass distribution more similar to a natural forearm and hand compared to contemporary prosthetics due to the more proximal location of the heavier components of the system. This paper describes the design of the hand and controller, as well as the test results.

  8. Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

    NARCIS (Netherlands)

    Habets, Jesse; Budde, Ricardo P.; Symersky, Petr; van den Brink, Renee B.; de Mol, Bas A.; Mali, Willem P.; van Herwerden, Lex A.; Chamuleau, Steven A.

    Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these

  9. Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

    NARCIS (Netherlands)

    Habets, Jesse; Budde, Ricardo P.; Symersky, Petr; van den Brink, Renee B.; de Mol, Bas A.; Mali, Willem P.; van Herwerden, Lex A.; Chamuleau, Steven A.

    2011-01-01

    Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these

  10. Role of CT in patients with prosthetic heart valves

    NARCIS (Netherlands)

    Suchá, D.

    2016-01-01

    Valvular heart disease accounts for a substantial part of the cardiovascular disease worldwide with an estimated prevalence of 2.5% in the Western population aged <65 years and over 13% in the population aged >75 years. Surgical prosthetic heart valve (PHV) replacement is the indicated therapy for

  11. Prosthetic prescription in the Netherlands : an observational study

    NARCIS (Netherlands)

    van der Linde, H; Geertzen, JHB; Hofstad, CJ; Postema, K; Van Limbeek, Jacques

    2003-01-01

    Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

  12. Perfluorinated polymer grafting: influence of preirradiation conditions

    International Nuclear Information System (INIS)

    Moura, E.; Somessari, E.S.R.; Silveira, C.G.; Paes, H.A.; Sousa, C.A.; Fernandes, W.; Manzoli, J.E; Geraldo, A.B.; Cardozo, P.

    2009-01-01

    The technological interest of perfluorinated polymers is related to its specific properties like low chemical reactivity and high mechanical and temperature resistance. The development of polymeric membranes for PEM fuel cell dispositives requires beyond these characteristics, a long-life time performance and low cost compared to Nafion membranes. By these material have high crystallinity, the radiation grafting indeed occurs but this process generate a low mechanical resistance aggregate. In this way, it is necessary to render the polymer with a low crystallinity or even amorphous. Generally, irradiation under polymer melt temperatures makes the crystallinity breaking and polymer crosslinking. The main objective of this work was promoting the crosslinking process into perfluorinated polymers by pre-irradiation method and to precede styrene grafting by electron beam irradiation in a second step. The experimental methodology consists in pre-irradiate perfluorinated polymers films like PTFE and PFA under high temperature (> 300 deg C) and vacuum conditions by electron beam irradiation at 5 kGy to 30 kGy doses and 2,85 kGy/s to 22,4 kGy/s dose rates. To obtain temperatures above 300 deg C, it was necessary construct a vacuum chamber with a heating system where temperature process could be follow up in real time. Some molecular alterations in polymeric matrix were analyzed by Mid-ATR-FTIR spectroscopy; macroscopic changes are verified by gravimetry. The styrene grafting onto these samples is realized by electron beam irradiation at doses between 30 and 100 kGy. These results are discussed. (author)

  13. Evaluation of peri-implant bone resorption around Straumann Bone Level implants placed in areas reconstructed with autogenous vertical onlay bone grafts.

    Science.gov (United States)

    Chiapasco, Matteo; Casentini, Paolo; Zaniboni, Marco; Corsi, Elena

    2012-09-01

    To evaluate the survival and success rate of Straumann Bone Level implants placed in vertically atrophied edentulous jaws previously reconstructed with autogenous onlay bone grafts taken from the calvarium or the mandibular ramus. From 2007 to 2009, 18 patients presenting with vertical deficits of the edentulous ridges were treated with autogenous cortical bone grafts harvested from the mandibular ramus or the calvarium. Four to seven months afterward, 60 Straumann Bone Level implants were placed in the reconstructed areas. After a further waiting period of 2-3 months, patients were rehabilitated with implant-supported fixed prostheses. Follow-up ranged from 12 to 36 months (mean: 19 months) after the start of prosthetic loading. Graft resorption before implant placement, as well as survival and success rates of implants, were recorded. The mean bone resorption prior to implant placement was 0.18 mm for calvarial grafts and 0.42 mm for ramus grafts. Survival rate was 100% either for implants placed in calvarial grafts or implants placed in ramus grafts, while success rate was 90.3% for implants placed in calvarial grafts, and 93.1% for implants placed in ramus grafts. Results from this study seem to demonstrate that implants with a platform-switching design may predictably integrate in edentulous areas reconstructed with autogenous bone grafts, with survival rates consistent with those reported in recent literature reviews on the same topic, and also with implants placed in native bone. Conversely, this study was not able to demonstrate that implants with platform-switching design may reduce bone resorption around implants placed in reconstructed areas. © 2011 John Wiley & Sons A/S.

  14. Robotic hand with locking mechanism using TCP muscles for applications in prosthetic hand and humanoids

    Science.gov (United States)

    Saharan, Lokesh; Tadesse, Yonas

    2016-04-01

    This paper presents a biomimetic, lightweight, 3D printed and customizable robotic hand with locking mechanism consisting of Twisted and Coiled Polymer (TCP) muscles based on nylon precursor fibers as artificial muscles. Previously, we have presented a small-sized biomimetic hand using nylon based artificial muscles and fishing line muscles as actuators. The current study focuses on an adult-sized prosthetic hand with improved design and a position/force locking system. Energy efficiency is always a matter of concern to make compact, lightweight, durable and cost effective devices. In natural human hand, if we keep holding objects for long time, we get tired because of continuous use of energy for keeping the fingers in certain positions. Similarly, in prosthetic hands we also need to provide energy continuously to artificial muscles to hold the object for a certain period of time, which is certainly not energy efficient. In this work we, describe the design of the robotic hand and locking mechanism along with the experimental results on the performance of the locking mechanism.

  15. Design, Sensing and Control of a Robotic Prosthetic Eye for Natural Eye Movement

    Directory of Open Access Journals (Sweden)

    J. J. Gu

    2006-01-01

    Full Text Available Loss of an eye is a tragedy for a person, who may suffer psychologically and physically. This paper is concerned with the design, sensing and control of a robotic prosthetic eye that moves horizontally in synchronization with the movement of the natural eye. Two generations of robotic prosthetic eye models have been developed. The first generation model uses an external infrared sensor array mounted on the frame of a pair of eyeglasses to detect the natural eye movement and to feed the control system to drive the artificial eye to move with the natural eye. The second generation model removes the impractical usage of the eye glass frame and uses the human brain EOG (electro-ocular-graph signal picked up by electrodes placed on the sides of a person's temple to carry out the same eye movement detection and control tasks as mentioned above. Theoretical issues on sensor failure detection and recovery, and signal processing techniques used in sensor data fusion, are studied using statistical methods and artificial neural network based techniques. In addition, practical control system design and implementation using micro-controllers are studied and implemented to carry out the natural eye movement detection and artificial robotic eye control tasks. Simulation and experimental studies are performed, and the results are included to demonstrate the effectiveness of the research project reported in this paper.

  16. [The biomechanical behaviour of the flexible acrylic partial prosthetics].

    Science.gov (United States)

    Gheban, E; Forna, Norina Consuela

    2008-01-01

    The simulation methods constitute a modern method absolutely necessary at the forerunner stage of the practical unwinding of the research stages, outlining the precise directions for the practical application, the final results influencing the dental practice. Our study proposes itself to analyze through the method of the finite element the status of the tension and the deformations registered at the level of the partially extended indentured prosthetic field and at the level of the partially flexible acrylic prosthetics. The first step was constituted by the realization of CT followed by their scanning and the usage of the material constants. Following the tomographic computer exam at the patients submitted to the study, it was observed a resorption and an important atrophy at the level of the jaw indented crest, after a period of four months, with the flexible prosthetics type Valplast, this aspect having profound clinical and viability implications to the selected therapy solution. For the 3D reconstruction of the different types of partial extended indentation the Amira universal program was used for the 3D reconstructions for any type of Tomographic Computer. Following the 3D reconstructions of the information obtained on the tomographic computer on the images it can be observed an important resorption of the jaw bone in the area of the edentulous space with an acrylic flexible prosthetics. The intrusion of the silicon material Rubber type, as a viable solution for the reduction of the absorption rate and atrophy of the partially indented prosthetics field, has results proportional to the type of the force applied and the applying of this. The simulation of the real clinical situations following the contribution of the tomographic computer constitutes a highly important stage in the evaluation of the degree of resorption and atrophy at the level of the indented crests, process whose parameters are influenced by the factorial accumulation with a profound impact

  17. Results of Infrainguinal Bypass with a Composite Graft Combining Polytetrafluoroethylene and Vein Graft in Absence of Appropriate Saphenous Vein Graft.

    Science.gov (United States)

    Jin, Myung Jae; Park, Ui Jun; Kim, Hyoung Tae; Roh, Young-Nam

    2017-06-01

    Use of a composite graft combining a polytetrafluoroethylene graft with an autogenous vein is an option for limb salvage in the absence of an adequate single segment vein graft. We aimed to investigate the results of infrainguinal bypass with a composite graft. We retrospectively reviewed 11 infrainguinal arterial bypasses on 11 limbs which underwent surgery from March 2012 to November 2016. Critical limb ischemia was common (63.6%) indication of bypass surgery and most (90.9%) of the patients had history of failed previous treatment including endovascular treatment (36.4%) and bypass surgery (72.7%). At the 2 years after graft implantations, primary patency and amputation-free survival of below-knee bypasses using composite graft were 73% and 76%, respectively. Infrainguinal arterial bypasses with composite graft had an acceptable patency. In patients without other alternative conduits for revascularization, bypass with a composite graft can be an option.

  18. Plant grafting: new mechanisms, evolutionary implications

    Directory of Open Access Journals (Sweden)

    Eliezer E Goldschmidt

    2014-12-01

    Full Text Available Grafting, an old plant propagation practice, is still widely used with fruit trees and in recent decades also with vegetables. Taxonomic proximity is a general prerequisite for successful graft-take and long-term survival of the grafted, composite plant. However, the mechanisms underlying interspecific graft incompatibility are as yet insufficiently understood. Hormonal signals, auxin in particular, are believed to play an important role in the wound healing and vascular regeneration within the graft union zone. Long-distance protein, mRNA and small RNA graft-transmissible signals currently emerge as novel mechanisms which regulate nutritional and developmental root/top relations and may play a pivotal role in grafting physiology. Grafting also has significant pathogenic projections. On one hand, stock to scion mechanical contact enables the spread of diseases, even without a complete graft union. But, on the other hand, grafting onto resistant rootstocks serves as a principal tool in the management of fruit tree plagues and vegetable soil-borne diseases. The ‘graft hybrid’ historic controversy has not yet been resolved. Recent evidence suggests that epigenetic modification of DNA-methylation patterns may account for certain graft-transformation phenomena. Root grafting is a wide spread natural phenomenon; both intraspecific and interspecific root grafts have been recorded. Root grafts have an evolutionary role in the survival of storm-hit forest stands as well as in the spread of devastating diseases. A more fundamental evolutionary role is hinted by recent findings that demonstrate plastid and nuclear genome transfer between distinct Nicotiana species in the graft union zone, within a tissue culture system. This has led to the formation of alloploid cells that, under laboratory conditions, gave rise to a novel, alloploid Nicotiana species, indicating that natural grafts may play a role in plant speciation. under certain circumstances.

  19. Plant grafting: new mechanisms, evolutionary implications.

    Science.gov (United States)

    Goldschmidt, Eliezer E

    2014-01-01

    Grafting, an old plant propagation practice, is still widely used with fruit trees and in recent decades also with vegetables. Taxonomic proximity is a general prerequisite for successful graft-take and long-term survival of the grafted, composite plant. However, the mechanisms underlying interspecific graft incompatibility are as yet insufficiently understood. Hormonal signals, auxin in particular, are believed to play an important role in the wound healing and vascular regeneration within the graft union zone. Incomplete and convoluted vascular connections impede the vital upward and downward whole plant transfer routes. Long-distance protein, mRNA and small RNA graft-transmissible signals currently emerge as novel mechanisms which regulate nutritional and developmental root/top relations and may play a pivotal role in grafting physiology. Grafting also has significant pathogenic projections. On one hand, stock to scion mechanical contact enables the spread of diseases, even without a complete graft union. But, on the other hand, grafting onto resistant rootstocks serves as a principal tool in the management of fruit tree plagues and vegetable soil-borne diseases. The 'graft hybrid' historic controversy has not yet been resolved. Recent evidence suggests that epigenetic modification of DNA-methylation patterns may account for certain graft-transformation phenomena. Root grafting is a wide spread natural phenomenon; both intraspecific and interspecific root grafts have been recorded. Root grafts have an evolutionary role in the survival of storm-hit forest stands as well as in the spread of devastating diseases. A more fundamental evolutionary role is hinted by recent findings that demonstrate plastid and nuclear genome transfer between distinct Nicotiana species in the graft union zone, within a tissue culture system. This has led to the formation of alloploid cells that, under laboratory conditions, gave rise to a novel, alloploid Nicotiana species, indicating

  20. Dutch evidence-based guidelines for amputation and prosthetics of the lower extremity : Rehabilitation process and prosthetics. Part 2

    NARCIS (Netherlands)

    Geertzen, Jan; van der Linde, Harmen; Rosenbrand, Kitty; Conradi, Marcel; Deckers, Jos; Koning, Jan; Rietman, Hans S.; van der Schaaf, Dick; van der Ploeg, Rein; Schapendonk, Johannes; Schrier, Ernst; Duijzentkunst, Rob Smit; Spruit-van Eijk, Monica; Versteegen, Gerbrig; Voesten, Harrie

    2015-01-01

    Background: A structured, multidisciplinary approach in the rehabilitation process after amputation is needed that includes a greater focus on the involvement of both (para)medics and prosthetists. There is considerable variation in prosthetic prescription concerning the moment of initial prosthesis

  1. Vascularized osseous graft for scaphoid

    International Nuclear Information System (INIS)

    Mendez Daza, Carlos Hernan; Mathoulin, Cristophe

    2004-01-01

    The most commonly used technique for treatment of pseudo-arthrosis of the scaphoid is osteo-synthesis with Kirschnet wires and cortical sponge grafts. Results reported by different teams using this procedure show no more than 90% osseous consolidation, especially in cases where vascularisation of the proximal fragment of the scaphoid is compromised. Here we present a series of ten cases of pseudo-arthrosis of the scaphoid, treated using a new surgical technique involving a vascularized osseous graft of the distal radius. Using this procedure we obtained 100% consolidation, with no complications either during the procedure or immediately post-operatively. Patients returned to work in week 15 on average. In 4 cases we observed discomfort in the area of the scar, which was successfully treated using local cortisone injection. The results obtained are very similar to those seen in the literature on the different techniques for vascularized osseous grafts for pseudo-arthrosis of the scaphoid

  2. Treatment of Recurrent Prosthetic Mitral Valve Thrombosis with Reteplase: A Report of Four Cases.

    Science.gov (United States)

    Behzadnia, Neda; Sharif Kashani, Babak; Kiani, Arda; Abedini, Atefe; Seyedi, Seyed Reza; Zargham Ahmadi, Hossein; Naghash Zadeh, Farah; Fakharian, Atefeh

    2016-01-01

    Thrombosis is a life threatening complications of prosthetic mitral valves and is associated with high morbidity and mortality. Even in presence of systemic anticoagulation prosthetic valve thrombosis has an incidence of 0.5% to 8%. Recurrent prosthetic valve thrombosis and the resulting thrombotic occlusion require re-establishment of blood flow across the valve. While surgical repair is considered the classic first line treatment option for prosthetic valve thrombosis, intravenous thrombolysis has emerged as an acceptable alternative for the first episode of prosthetic valve thrombosis. Due to the limitation of using streptokinase in recurrent thrombotic events, fibrin-specific tissue plasminogen activators have been successfully utilized to treat cases of recurrent prosthetic valve thrombosis. In this case-series, we have reported four cases of recurrent prosthetic valve thrombosis that were successfully treated with Reteplase at our hospital.

  3. sEMG Sensor Using Polypyrrole-Coated Nonwoven Fabric Sheet for Practical Control of Prosthetic Hand.

    Science.gov (United States)

    Jiang, Yinlai; Togane, Masami; Lu, Baoliang; Yokoi, Hiroshi

    2017-01-01

    One of the greatest challenges of using a myoelectric prosthetic hand in daily life is to conveniently measure stable myoelectric signals. This study proposes a novel surface electromyography (sEMG) sensor using polypyrrole-coated nonwoven fabric sheet as electrodes (PPy electrodes) to allow people with disabilities to control prosthetic limbs. The PPy electrodes are sewn on an elastic band to guarantee close contact with the skin and thus reduce the contact electrical impedance between the electrodes and the skin. The sensor is highly customizable to fit the size and the shape of the stump so that people with disabilities can attach the sensor by themselves. The performance of the proposed sensor was investigated experimentally by comparing measurements of Ag/AgCl electrodes with electrolytic gel and the sEMG from the same muscle fibers. The high correlation coefficient (0.87) between the two types of sensors suggests the effectiveness of the proposed sensor. Another experiment of sEMG pattern recognition to control myoelectric prosthetic hands showed that the PPy electrodes are as effective as Ag/AgCl electrodes for measuring sEMG signals for practical myoelectric control. We also investigated the relation between the myoelectric signals' signal-to-noise ratio and the source impedances by simultaneously measuring the source impedances and the myoelectric signals with a switching circuit. The results showed that differences in both the norm and the phase of the source impedance greatly affect the common mode noise in the signal.

  4. Brånemark and ITI dental implants in the human bone-grafted maxilla: a comparative evaluation

    DEFF Research Database (Denmark)

    Pinholt, Else M

    2003-01-01

    and the patients were followed between 20 and 67 months post implantation. The bone graft was transplanted to add bony volume in the maxillary sinus, the anterior floor of the nose and/or the alveolar ridge. After a healing period of 4(1/2) months, dental implants were inserted and left for healing for 8 months....... Twelve consecutive patients received machine-surfaced Brånemark fixtures and 13 consecutive patients received SLA-ITI fixtures. Gradual loading was applied after healing abutment application. After 6 months the permanent prosthetic reconstruction was provided to the patient, either as a fixed...

  5. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    Science.gov (United States)

    Zhang, Huanxia; Li, Wei

    2015-11-01

    Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid-base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as Csbnd O, Cdbnd O, and Osbnd Cdbnd O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the plasma-grafting treatments.

  6. Crosslinked Radiation-Grafted Films

    Energy Technology Data Exchange (ETDEWEB)

    Slaski, M.; Brack, H.P.; Fischer, D. [Zuercher Hochschule Winterthur (Switzerland); Peter, G. [Zuercher Hochschule Winterthur (Switzerland); Wokaun, A.; Scherer, G.G.

    2004-03-01

    Radiation-grafted membranes prepared by using styrene (S) and divinyl benzene (DVB) as graft components and subsequent sulfonation can be applied as solid polymer electrolytes in fuel cells and other electrochemical devices. The use of DVB as crosslinker has an important influence on the ex-situ properties like swelling, ionic resistivity, mechanical properties, surface energy, and oxidative stability. DVB also influences gas crossover, polarization performance, and lifetime in the fuel cell application. In spite of this importance, the actual DVB content and its extent of reaction has not been well investigated. (author)

  7. Reconstruction of mandible with pedicle bone grafts.

    Science.gov (United States)

    Kowalik, S

    1980-02-01

    Three cases of pedicle bone grafts used to reconstruct the mandible are presented. The grafts were taken from the shoulder blade, rib and clavicle. In two patients partial and in one patient total mandibles were reconstructed. Good results were obtained.

  8. Evaluation of Replacement Grafts and Punch Grafts in the Treatment of Vitiligo

    Directory of Open Access Journals (Sweden)

    Singh Ajit Kumar

    1980-01-01

    Full Text Available Thirtycasesof vitiligo eachwithminimum of two lesions undent replacement graft and multiple punch grafts in one lesion each. Complications observed at the recipient site like infection and raised nigosed surface were significantly more in replacement grafts. Hypopigmentation of the graft was significantly more when the disease was progressive.

  9. Progressing takayasu arteritis successfully treated by common carotid-internal carotid crossover bypass grafting: technical case report.

    Science.gov (United States)

    Hiu, Takeshi; Kitagawa, Naoki; Suyama, Kazuhiko; Nagata, Izumi

    2008-05-01

    This report describes a unique case of Takayasu arteritis with occlusion of the left common carotid artery (CCA) and the right internal carotid artery (ICA), which was successfully treated by right CCA-left ICA crossover bypass grafting using the saphenous vein. The histological findings of the original occluded prosthetic graft are also described. A 63-year-old woman with a history of Takayasu arteritis was admitted to our hospital with a history of progressive dizziness, frequent syncopal attacks, and repetitive blurred vision in the left eye. She had undergone repeat transthoracic bypass surgeries, including grafting with the use of a Gore-Tex (W.L. Gore & Associates, Inc., Flagstaff, AZ) prosthesis between the left external ilioaxillary bypass and the left CCA. However, cerebral angiography demonstrated total occlusion of the left CCA, the right ICA, and the bilateral subclavian arteries. On admission, I-iodoamphetamine single-photon emission computed tomography showed a decreased cerebrovascular reactivity to acetazolamide in the bilateral cerebral hemispheres. Moreover, cerebral angiography revealed an occlusion of the Gore-Tex graft, whereas the left ICA was opacified through the retrograde filling in the left external carotid artery. Crossover bypass grafting was performed using the saphenous vein between the right CCA and the left ICA. The Gore-Tex graft was partially removed, and myointimal hypertrophy with an inflammatory response around the wall was found histologically. The postoperative course was uneventful. A normalized cerebrovascular reserve in both cerebral hemispheres was demonstrated on I-iodoamphetamine single-photon emission computed tomography. Although it is not frequently indicated, crossover bypass grafting using the saphenous vein between bilateral carotid arteries is considered to be a feasible alternative procedure in patients with Takayasu arteritis.

  10. Effect of prosthetic restoration on implant survival and success.

    Science.gov (United States)

    Rammelsberg, Peter; Lorenzo-Bermejo, Justo; Kappel, Stefanie

    2017-10-01

    The objective of this work was to evaluate the effect of prosthetic restoration on the survival of implants and on the incidence of implant-related complications. From a prospectively documented clinical study, 1569 implants placed in 630 patients (mean age 59.56 years) were evaluated. Selection criteria were a conventional loading protocol, prosthetic restoration with at least one follow-up, and a minimum observation period of 9 months. Implants that failed before prosthetic restoration were excluded. The sample included 1345 tissue-level implants and 104 bone-level implants (Straumann), and 120 Replace implants (Nobel Biocare). The observation period ranged between 9 months and 11 years after prosthetic restoration (mean 4.0 years; SD 2.5). The implants were restored with single crowns (n = 557), fixed dental prostheses (n = 594), or removable dental prostheses (RDP) (n = 418). In the RDP group, 356 implants were restored with telescoping crowns, 22 with bar units 24 with bar joints, and 16 with locator attachments. The incidence of implant-related complications and failures was analyzed by use of Kaplan-Meier survival curves. Cox regression analysis was used to identify possible risk factors. Twenty-seven failures (1.8%; loosened or removed implants) were observed after prosthetic restoration; the incidence of failure was 3% for implants placed in males and 1% for implants placed in females. Other factors had no effect on the incidence of failure. Peri-implantitis (n = 29) and marginal bone loss >2 mm without acute inflammation (n = 6) also resulted in a 4% incidence of severe implant-related complications (62 of 1569; success 96%). Cox regression analysis revealed combined tooth-implant-supported restorations as a significant risk-reducing factor for severe implant-related complications (hazard ratio, HR = 0.34; P = 0.04). There was, furthermore, a tendency toward a greater incidence of complications for implants restored with RDPs than for

  11. Initial Clinical Evaluation of the Modular Prosthetic Limb

    Directory of Open Access Journals (Sweden)

    Briana N. Perry

    2018-03-01

    Full Text Available The Modular Prosthetic Limb (MPL was examined for its feasibility and usability as an advanced, dexterous upper extremity prosthesis with surface electromyography (sEMG control in with two individuals with below-elbow amputations. Compared to currently marketed prostheses, the MPL has a greater number of sequential and simultaneous degrees of motion, as well as wrist modularity, haptic feedback, and individual digit control. The MPL was successfully fit to a 33-year-old with a trans-radial amputation (TR01 and a 30-year-old with a wrist disarticulation amputation (TR02. To preserve anatomical limb length, we adjusted the powered degrees of freedom of wrist motion between users. Motor training began with practicing sEMG and pattern recognition control within the virtual integration environment (VIE. Prosthetic training sessions then allowed participants to complete a variety of activities of daily living with the MPL. Training and Motion Control Accuracy scores quantified their ability to consistently train and execute unique muscle-to-motion contraction patterns. Each user also completed one prosthetic functional metric—the Southampton Hand Assessment Procedure (SHAP for TR01 and the Jebsen-Taylor Hand Function Test (JHFT for TR02. Haptic feedback capabilities were integrated for TR01. TR01 achieved 95% accuracy at 84% of his VIE sessions. He demonstrated improved scores over a year of prosthetic training sessions, ultimately achieving simultaneous control of 13 of the 17 (76% attempted motions. His performance on the SHAP improved from baseline to final assessment with an increase in number of tasks achieved. TR01 also used vibrotactile sensors to successfully discriminate between hard and soft objects being grasped by the MPL hand. TR02 demonstrated 95% accuracy at 79% of his VIE sessions. He demonstrated improved scores over months of prosthetic training sessions, however there was a significant drop in scores initially following a mid

  12. The effect of acid on the radiation-induced grafting of styrene to polyethylene

    International Nuclear Information System (INIS)

    Chappas, W.J.; Silverman, J.

    1979-01-01

    In this work experiments were performed in O 2 -free systems. γ-irradiation of polyethylene films immersed in styrene-methanol solutions both with and without sulfuric acid, show the grafting rate is enhanced by the presence of acid despite the fact that the acid does not permeate the film. Experimental results are presented to show how the grafting rate depends on the composition of both the film and the liquid in which it is immersed. The results indicate that hydrogen atoms are not involved in the grafting reaction. (author)

  13. Endovascular repair of an innominate artery pseudoaneurysm using the Valiant Mona LSA branched graft device

    Directory of Open Access Journals (Sweden)

    Josh A. Sibille, MD

    2017-03-01

    Full Text Available A 60-year-old woman involved in a motor vehicle collision presented with a traumatic pseudoaneurysm of the innominate artery origin in addition to multiple concomitant injuries. She was classified as a high-risk candidate for open repair. An experimental thoracic branched graft device was used for coverage of the injury with the addition of a right carotid-to-left carotid-to-left subclavian artery bypass. Follow-up imaging showed resolution of the pseudoaneurysm and patency of her bypass grafts. This is the first described use of the Mona LSA Branch Thoracic Stent Graft System (Medtronic, Minneapolis, Minn in the innominate artery.

  14. [Redo ascending aorta replacement using a homograft for graft infection caused by methicillin-resistant Staphylococcus aureus; report of an emergently air-transferred case just after Great East Japan Earthquake].

    Science.gov (United States)

    Nakamura, Ken; Uchida, Tetsuro; Yoshimura, Yukihiro; Kim, Cholsu; Maekawa, Yoshiyuki; Minagawa, Tadanori; Mizumoto, Masahiro; Yamashita, Atsushi; Sadahiro, Mitsuaki; Saiki, Yoshikatsu; Kawamoto, Shunsuke

    2012-10-01

    We describe a case of replacement with a cryopreserved homograft for graft infection. A 48-year-old man had been performed ascending aorta replacement using woven dacron graft for type A aortic dissection. Two months ago, methicillin-resistant Staphylococcus aureus infection was suspected because of high-grade fever. Computed tomography (CT) scan revealed abscess formation around the prosthetic graft and redo operation using cryopreserved homograft was scheduled to avoid re-infection into mediastinum at Tohoku University Hospital, an institute cooperating with University of Tokyo tissue bank. However, Catastrophic Great East Japan Earthquake occurred the day before the scheduled date, and the patient could not have an operation at the institution. He was transferred to our hospital by helicopter. Then homograft was successfully implanted in ascending aorta after complete excision of infectious graft.

  15. The caudal septum replacement graft.

    Science.gov (United States)

    Foda, Hossam M T

    2008-01-01

    To describe a technique for reconstructing the lost tip support in cases involving caudal septal and premaxillary deficiencies. The study included 120 patients with aesthetic and functional nasal problems resulting from the loss of caudal septal and premaxillary support. An external rhinoplasty approach was performed to reconstruct the lost support using a cartilaginous caudal septum replacement graft and premaxillary augmentation with Mersilene mesh. The majority of cases (75%) involved revisions in patients who had previously undergone 1 or more nasal surgical procedures. A caudal septum replacement graft was combined with premaxillary augmentation in 93 patients (77.5%). The mean follow-up period was 3 years (range, 1-12 years). The technique succeeded in correcting the external nasal deformities in all patients and resulted in a significant improvement in breathing in 74 patients (86%) with preoperative nasal obstruction. There were no cases of infection, displacement, or extrusion. The caudal septum replacement graft proved to be very effective in restoring the lost tip support in patients with caudal septal deficiency. Combining the graft with premaxillary augmentation using Mersilene mesh helped increase support and stability over long-term follow-up.

  16. Endovascular stent grafting: a review

    International Nuclear Information System (INIS)

    Kribs, S.

    2001-01-01

    Endovascular stent grafts are intravascular devices composed of surgical graft material and a metallic frame, (Fig. 1). Their main application has been to treat aneurysms, but they have been used in vascular trauma and are being investigated for use in occlusive disease. Their advantage in treating aneurysms over conventional surgical treatment is that they are loaded into relatively small delivery systems (Fig. 2) and can be introduced to the area of interest from a remote site - usually the femoral artery. This avoids the morbidity of surgical exposure in difficult sites, such as the thoracic aorta, and lessens the cardiovascular stress to patients by eliminating the need to surgically cross-clamp the vessel being treated. The first description of abdominal aortic aneurysm exclusion by an endovascular stent graft was provided by Parodi and colleagues in 1991. Much of the early clinical experience in endovascular stent grafting was obtained from centres in Australia and Europe, and they are now reporting midterm follow-up data. There are now many centres in Canada and the United States involved in endovascular research and practice. (author)

  17. SOME TECHNIQUES IN CORNEAL GRAFTING

    African Journals Online (AJOL)

    1971-04-10

    Apr 10, 1971 ... simulate as nearly as possible the intra-ocular tension of the recipient. In this manner the apposition of the graft to the host cornea is as satisfactory as .... rected to 6/9 in spite of distortion and encroachment of the fibrotic process on the pupillary area. There has been no recurrence and inspection shows.

  18. Increasing the Thermal Conductivity of Graphene-Polyamide-6,6 Nanocomposites by Surface-Grafted Polymer Chains: Calculation with Molecular Dynamics and Effective-Medium Approximation.

    Science.gov (United States)

    Gao, Yangyang; Müller-Plathe, Florian

    2016-02-25

    By employing reverse nonequilibrium molecular dynamics simulations in a full atomistic resolution, the effect of surface-grafted chains on the thermal conductivity of graphene-polyamide-6.6 (PA) nanocomposites has been investigated. The interfacial thermal conductivity perpendicular to the graphene plane is proportional to the grafting density, while it first increases and then saturates with the grafting length. Meanwhile, the intrinsic in-plane thermal conductivity of graphene drops sharply as the grafting density increases. The maximum overall thermal conductivity of nanocomposites appears at an intermediate grafting density because of these two competing effects. The thermal conductivity of the composite parallel to the graphene plane increases with the grafting density and grafting length which is attributed to better interfacial coupling between graphene and PA. There exists an optimal balance between grafting density and grafting length to obtain the highest interfacial and parallel thermal conductivity. Two empirical formulas are suggested, which quantitatively account for the effects of grafting length and density on the interfacial and parallel thermal conductivity. Combined with effective medium approximation, for ungrafted graphene in random orientation, the model overestimates the thermal conductivity at low graphene volume fraction (f 10%). For unoriented grafted graphene, the model matches the experimental results well. In short, this work provides some valuable guides to obtain the nanocomposites with high thermal conductivity by grafting chain on the surface of graphene.

  19. Intracortical neural interface for prosthetic applications.

    Science.gov (United States)

    Ortmann, Valerij; Baziyan, Boris Kh

    2007-01-01

    New design of intracortical penetrating electrodes with integrated electronic front end is presented. The main advantage of the presented manufacturing technology is a simple customization of the electrode lengths and arrangement, according to the brain geometry of the specific patient. The neural interface may be used for the stimulation of the inner cortical layers and for recording of evoked potentials. Experimental investigations on several cats have shown the higher effectiveness of the intracortical stimulation of the primary visual cortex in comparison to surface electrodes.

  20. [Spectral analysis and LDB based classification of heart sounds with mechanical prosthetic heart valves].

    Science.gov (United States)

    Zhang, Di; Wu, Yuequan; Yao, Jianping; Yang, Song; Du, Minghui

    2011-12-01

    Auscultation, the act of listening for heart sounds to aid in the diagnosis of various heart diseases, is a widely used efficient technique by cardiologists. Since the mechanical prosthetic heart valves are widely used today, it is important to develop a simple and efficient method to detect abnormal mechanical valves. The study on five different mechanical valves showed that only the case of perivalvular leakage could be detected by spectral estimation. Though it is possible to classify different mechanical valves by using time-frequency components of the signal directly, the recognition rate is merely 84%. However, with the improved local discriminant bases (LDB) algorithm to extract features from heart sounds, the recognition rate is 97.3%. Experimental results demonstrated that the improved LDB algorithm could improve classification rate and reduce computational complexity in comparison with original LDB algorithm.

  1. On the open/close performance of prosthetic heart valves at high frequencies

    Science.gov (United States)

    Beltran, A.; Zenit, R.

    2013-11-01

    We report experimental observations of the performance of mechanical and biological prosthetic heart valves. The valves are mounted in a test circular channel conected to a flow system that emulates accelerated human-like conditions. The flow is generated by a high frequencie pulsative pump (in the range of 7 to 18 Hz). The objective of the investigation is to find the treshold conditions for which the open/close performance fails. Preliminary results show that for the mechanical valve the failure starts at 436 pulses/min, while for the biological valve, it starts a failing performance is observed for frequencies higher that 462 pulses/min. Even though these values are far from the heart rate in the human body, we use these measurements to further understand the structure-fluid interaction mechanics of the flow through heart valves.

  2. Fluxional behavior of molecular WMe6 and of silica grafted WMe6

    KAUST Repository

    Credendino, Raffaele

    2015-02-09

    Using DFT methods we describe the fluxional behavior of mono-, bi-, and tripodal W(CH3)6 species grafted on partially dehydroxylated silica. Our results show that the umbrella inversion mechanism described to explain the fluxionality of the parent W(CH3)6 molecule is not operative after grafting on silica. Low-energy turnstile rotations are instead operative for all considered species, correlating the experimental values found in solid-state NMR.

  3. Classification of prosthetics used in hernia repair based on weight and biomaterial.

    Science.gov (United States)

    Coda, A; Lamberti, R; Martorana, S

    2012-02-01

    The aim of this study was to classify the polymeric prosthetics used for hernia repair based on biomaterial composition and weight in an effort to clarify to surgeons what kinds of material they are dealing with and to provide a standardized system of categorization. An intensive research effort was carried out on prosthetics that are commercially available worldwide. We conducted a search of the medical literature and companies' websites to find the weights and thicknesses of commercially available prosthetics. Where these data were lacking, we contacted manufacturers directly in order to render the research more complete. A total of 166 products were considered for classification based on biomaterial properties. Among these, a homogeneous group of 80 polypropylene monofilament knitted or woven prosthetics was selected for classification based on weight. Weights were provided for 70 prosthetics (87%), and both the weight and thickness was provided for 40 prosthetics (50%). Classification based on weight: Ultra-light prosthetics made of one pure biomaterial); composite (prosthetics made of two or more different layers); combined (prosthetics made of two materials knitted or woven together); and biologic. Weight and biomaterial classifications were proposed after an extensive analysis of commercially available prosthetics. The need for a common terminology is important to avoid misunderstandings among clinicians and technicians.

  4. Customized mold radiotherapy with prosthetic apparatus for oral cancers

    International Nuclear Information System (INIS)

    Noguchi, Tadahide; Tsuchiya, Yoshiyuki; Hayasaka, Junichi; Itoh, Hiroto; Jinbu, Yoshinori; Kusama, Mikio; Takahashi, Satoru; Nakazawa, Masanori

    2014-01-01

    Eight patients (6 males, 2 females; median age, 78 years; age range, 31-94 years) were treated by mold radiotherapy with a prosthetic apparatus for oral cancers between October 2006 and March 2013. The primary sites were the tongue in 3 cases, hard palate and buccal mucosa in 2 cases each, and oral floor in 1 case. The type of treatment consisted of radical radiotherapy and palliative radiotherapy in 2 cases each, and preoperative radiotherapy, postoperative radiotherapy, additional radiotherapy after external beam radiotherapy and systemic chemotherapy in 1 case each. Patients received 40-50 Gy in 8-10 fractions with mold radiotherapy. Two patients who received radical radiotherapy showed no signs of recurrence or metastasis. The present therapy contributed to patients' palliative, postoperative, and preoperative therapy. Mold radiotherapy with a prosthetic appliance was performed safely and was a useful treatment for several types of oral cancer. (author)

  5. Prosthetic Rehabilitation in Partially Edentulous Elders – A Case Report

    Science.gov (United States)

    PICOS, ALINA MONICA; DONCA, VALER; PICOS, ANDREI

    2014-01-01

    Complex treatment involving removable articulated to fixed prostheses is indicated in extended edentulous areas, which represent clinical conditions more frequently encountered in elderly patients. A number of aspects must be considered in elderly patients before starting the therapy: physical and mental condition, self-care capacity, time and cost of treatment, predictability. In institutionalized elders, suffering of systemic diseases, the therapy of choice should be the least invasive and able to restore function at an acceptable level. Active healthy elders can be beneficiaries of complex prosthetic treatments involving many long sessions and difficult treatments. We present a case of a 74 year-old male with extended maxillary edentulous areas, in whom a complex prosthetic treatment was performed. PMID:26528025

  6. Self-cleaning skin-like prosthetic polymer surfaces

    Science.gov (United States)

    Simpson, John T [Clinton, TN; Ivanov, Ilia N [Knoxville, TN; Shibata, Jason [Manhattan Beach, CA

    2012-03-27

    An external covering and method of making an external covering for hiding the internal endoskeleton of a mechanical (e.g., prosthetic) device that exhibits skin-like qualities is provided. The external covering generally comprises an internal bulk layer in contact with the endoskeleton of the prosthetic device and an external skin layer disposed about the internal bulk layer. The external skin layer is comprised of a polymer composite with carbon nanotubes embedded therein. The outer surface of the skin layer has multiple cone-shaped projections that provide the external skin layer with superhydrophobicity. The carbon nanotubes are preferably vertically aligned between the inner surface and outer surface of the external skin layer in order to provide the skin layer with the ability to transmit heat. Superhydrophobic powders may optionally be used as part of the polymer composite or applied as a coating to the surface of the skin layer to enhance superhydrophobicity.

  7. Can we close large prosthetic space with orthodontics?

    Science.gov (United States)

    Mesko, Mauro Elias; Skupien, Jovito Adiel; Valentini, Fernanda; Pereira-Cenci, Tatiana

    2013-01-01

    For years, the treatment for the replacement of a missing tooth was a fixed dental prosthesis. Currently, implants are indicated to replace missing teeth due to high clinical success and with the advantage of not performing preparations in the adjacent tooth. Another option for space closure is the use of orthodontics associated to miniscrews for anchorage allowing better control of the orthodontic biomechanics and especially making possible closure of larger prosthetic spaces. Thus, this article describes two cases with indications and discussion of the advantages and disadvantages of using orthodontics for prosthetic spaces closure. The cases herein presented show that it is possible to close an space when there are available teeth in the adjacent area. It can be concluded that when a malocclusion is present there will be a strong trend to indicate space closure by orthodontic movement as it preserves natural teeth and seems a more physiological approach.

  8. Mechanical Prosthetic Valves and Pregnancy: A therapeutic dilemma of anticoagulation

    Directory of Open Access Journals (Sweden)

    Prashanth Panduranga

    2014-10-01

    Full Text Available Choosing the best anticoagulant therapy for a pregnant patient with a mechanical prosthetic valve is controversial and the published international guidelines contain no clear-cut consensus on the best approach. This is due to the fact that there is presently no anticoagulant which can reliably decrease thromboembolic events while avoiding damage to the fetus. Current treatments include either continuing oral warfarin or substituting warfarin for subcutaneous unfractionated heparin or low-molecular-weight heparin (LMWH in the first trimester (6–12 weeks or at any point throughout the pregnancy. However, LMWH, while widely-prescribed, requires close monitoring of the blood anti-factor Xa levels. Unfortunately, facilities for such monitoring are not universally available, such as within hospitals in developing countries. This review evaluates the leading international guidelines concerning anticoagulant therapy in pregnant patients with mechanical prosthetic valves as well as proposing a simplified guideline which may be more relevant to hospitals in this region.

  9. Single implant restorations: prosthetically induced soft tissue topography.

    Science.gov (United States)

    Bichacho, N; Landsberg, C J

    1997-09-01

    An aesthetic transition from the smaller diameter of the implant to the prosthetic restoration that resembles the size of the natural tooth has presented an ongoing challenge to the implant restorative dentists. The appearance of the surrounding soft tissue is of major importance, and various techniques have been developed to guide and optimize its topography. The learning objective of this article is to present a cervical contouring concept, whereby the soft tissue topography is optimally determined already in the laboratory phase. Using a custom abutment and provisional crown as components of the transmucosal prosthetic unit (TPU), the topography is transferred to the vital intraoral tissues, which predictably adapt to the enhanced aesthetic configuration. Clinical cases are presented to demonstrate the sequence of the technique in treating the anterior region of the maxilla.

  10. Functional Assessment of a Myoelectric Postural Controller and Multi-Functional Prosthetic Hand by Persons With Trans-Radial Limb Loss.

    Science.gov (United States)

    Segil, Jacob L; Huddle, Stephen A; Weir, Richard F Ff

    2017-06-01

    The functional assessment of myoelectric control algorithms by persons with amputation promotes the overarching goal of the field of prosthetic limb design: to replace what was lost. However, many studies use experimental paradigms with virtual interfaces and able-bodied subjects that do not capture the challenges of a clinical implementation with an amputee population. A myoelectric control system must be robust to variable physiology, loading effects of the prosthesis on the limb, and limb position effects during dynamic tasks. Here persons with transradial limb loss performed activities of daily living using a postural controller and multi-functional prosthetic hand in order to verify that the postural controller was robust to these clinical challenges. The Southampton Hand Assessment Procedure was performed by persons with limb loss and able-bodied subjects. The results indicate that persons with limb loss and able-limbed subjects achieved the same performance and therefore that the clinical challenges were overcome. Persons with limb loss achieved 55% of physiological hand function on average. Also, the postural controller is compared to other state of the art myoelectric controllers and prosthetic hands previously tested. This work confirms that the postural controller is potentially a clinically-viable method to control myoelectric multi-functional prosthetic hands.

  11. Osteotome-Mediated Sinus Lift without Grafting Material: A Review of Literature and a Technique Proposal

    Directory of Open Access Journals (Sweden)

    Silvio Taschieri

    2012-01-01

    Full Text Available Implant rehabilitation of the edentulous posterior maxilla may be a challenging procedure in the presence of insufficient bone volume for implant placement. Maxillary sinus augmentation with or without using grafting materials aims to provide adequate bone volume. The aim of the present study was to systematically review the existing literature on transalveolar maxillary sinus augmentation without grafting materials and to propose and describe an osteotome-mediated approach in postextraction sites in combination with platelet derivative. The systematic review showed that high implant survival rate (more than 96% after 5 years can be achieved even without grafting the site, with a low rate of complications. Available alveolar bone height before surgery was not correlated to survival rate. In the described case report, three implants were placed in posterior maxilla after extraction of two teeth. An osteotome-mediated sinus lifting technique was performed with the use of platelet derivative (PRGF; a synthetic bone substitute was used to fill the gaps between implant and socket walls. No complications occurred, and implants were successfully in site after 1 year from prosthetic loading. The presented technique might represent a viable alternative for the treatment of edentulous posterior maxilla with atrophy of the alveolar bone though it needs to be validated by studies with a large sample size.

  12. [Revascularization surgery of an anuric solitary kidney using the left colic artery as a free graft].

    Science.gov (United States)

    da Gama, A Dinis; Nunes, J Silva; Cunha e Sá, Diogo; Pedro, Luís Mendes

    2003-01-01

    The thrombotic occlusion of one renal artery may become completely asymptomatic, due to the functionality of the contralateral kidney. However, in rare circumstances, such is the case of individuals with a solitary kidney, a situation of anuria and acute renal failure may constitute the main presentation of the condition. The authors report the clinical case of a 43 year old male patient, with the previous diagnosis of an infrarenal aortic occlusion and a single left kidney, who developed a thrombotic occlusion of the renal artery, with anuria and acute renal failure. The patient underwent an emergency revascularization procedure, consisting in the implantation of a prosthetic bypass graft from the superceliac aorta to the renal artery, with immediate recovery of the diuresis and renal function. Seventeen months later as a consequence of an anastomotic hyperplasia, an occlusion of the bypass graft occurred, again with anuria and acute renal failure. The patient was reoperated on and due to the inadequacy of both saphenous veins to be used as the material of choice for the revascularization procedure, a redundant segment of the left colic artery (Riolan's arcade) was removed and used as an interposition graft, from the middle colic artery to the renal artery, followed by an immediate restoration of diuresis and renal function. The singular and recurrent character of this clinical condition and the utilization of an original, eventually unique and well succeeded revascularization procedure, prompted its presentation and divulgation.

  13. Radiochemical grafting of acryonitrile on polystyrene

    International Nuclear Information System (INIS)

    Jendrychowska-Bonamour, A.M.; Michot, C.

    1977-01-01

    Polystyrene polyacrylonitrile copolymers have been prepared by the direct radio-induced grafting method. The reaction has been carried out in a gel of polystyrene swollen by the monomer. The ungrafted polystyrene has been extracted by toluene. It has been possible to separate grafted copolymers from homopolymer traces, despite the very strong dipole-dipole interactions exhibited in solution between polyacrylonitrile chains; afterwards these grafted copolymers were fractionated by composition. The limits of solubility and the glass transition temperatures of the grafted copolymers have been determined. The properties of grafted copolymers have been compared with those of block polyacrylonitrile copolymers. (authors)

  14. Homogeneous cation exchange membrane by radiation grafting

    International Nuclear Information System (INIS)

    Kolhe, Shailesh M.; G, Agathian; Ashok Kumar

    2001-01-01

    Preparation of a strong cation exchange membrane by radiation grafting of styrene on to polyethylene (LDPE) film by mutual irradiation technique in the presence of air followed by sulfonation is described. The grafting has been carried out in the presence of air and without any additive. Low dose rate has been seen to facilitate the grafting. Further higher the grafting percentage more is the exchange capacity. The addition of a swelling agent during the sulfonation helped in achieving the high exchange capacity. The TGA-MASS analysis confirmed the grafting and the sulfonation. (author)

  15. Neural-Network Control Of Prosthetic And Robotic Hands

    Science.gov (United States)

    Buckley, Theresa M.

    1991-01-01

    Electronic neural networks proposed for use in controlling robotic and prosthetic hands and exoskeletal or glovelike electromechanical devices aiding intact but nonfunctional hands. Specific to patient, who activates grasping motion by voice command, by mechanical switch, or by myoelectric impulse. Patient retains higher-level control, while lower-level control provided by neural network analogous to that of miniature brain. During training, patient teaches miniature brain to perform specialized, anthropomorphic movements unique to himself or herself.

  16. Effect of comprehensive prosthetic rehabilitation program for Intelligent Prosthesis users

    OpenAIRE

    Nagakura, Y.; Chin, T.; Furukawa, H.

    2004-01-01

    The aim of this research was to divide Intelligent Prosthesis users into one group which only received conventional training in prosthetic walking (referred to below as the conventional training group) and another group which received the comprehensive training devised by our center to test the functions of Intelligent Prostheses (referred to below as the comprehensive training group), in order to compare walking ability, with reference to energy consumption, in the two groups. The comprehens...

  17. Lactococcus garvieae Endocarditis on a Prosthetic Biological Aortic Valve.

    Science.gov (United States)

    Tsur, A; Slutzki, T; Flusser, D

    2015-09-01

    Lactococcus garvieae (LG) endocarditis is a rare disease in humans. There are only about 16 reported cases in the world. We report a 76-year-old male patient with LG endocarditis. In depth interview with the patient revealed that 2 weeks prior to admission, he had eaten sushi containing raw fish. Unlike many of the other infections reported, which were on a native mitral valve, our patient's vegetation was on a prosthetic aortic valve. © 2014 Blackwell Verlag GmbH.

  18. Prosthetic rehabilitation for a patient with microstomia: a case report

    Directory of Open Access Journals (Sweden)

    Moslehifard E

    2011-04-01

    Full Text Available "nFabrication of dental prosthesis for patients with microstomia has long been a problem for dentists. Microstomia is defined as an abnormally small oral orifice. Prosthetic rehabilitation of microstomia patients presents difficulties at all stages, from the preliminary impressions to fabrication of prosthesis. This study described a method for making impressions for patients with limited opening of the oral cavity which the use of a full-size impression tray was not possible.

  19. Improved design and development of a functional moulded prosthetic foot.

    Science.gov (United States)

    Narayanan, Govindarajan; Gnanasundaram, Saraswathy; Ranganathan, Mohan; Ranganathan, Rajaraman; Gopalakrishna, Gautham; Das, Bhabendra Nath; Mandal, Asit Baran

    2016-01-01

    In the Indian scenario, the Jaipur foot is a low-cost breakthrough that enabled the disabled person to adapt to the Indian environment. The aim of this study is to modify the present foot in terms of ankle support design and method of fabrication, foot moulds profile and the inner core material in order to improve the performance and durability. The optimized design of ankle support and flat foot profile moulds suitable for both left and right foot were developed through CAD/CAM and prosthetic feet were fabricated using ethylene vinyl acetate (EVA) foam as an appropriate alternative core material for microcellular rubber (MCR). The developed prosthetic feet were tested for rigidity by load-deflection analysis in universal testing machine. EVA foot had shown better rigidity than conventional MCR foot, which will help in weight transfer during walking and increase the durability. The CAD modeled ankle support and single block EVA had made the manufacturing process easy and reduced the weight of foot and improved Gait to the person fitted with it due to improved flat foot profile. The new artificial foot had proven to be efficacious technically as well as functionally, which is clearly borne out from the extremely positive feedback given by the amputees. Implications of Rehabilitation Persons with below knee amputation are usually provided with transtibial prosthesis, which allows for easier ambulation and helps them to get back to their normal life. Transtibial prosthesis is an artificial limb that replaces a lower limb that is amputated below the knee. In our study, a new prosthetic foot with a modified ankle support and flat foot profile using better inner-core material than the conventional Jaipur foot was developed and the process was also optimized for mass production. The developed prosthetic foot can be fitted with both above and below knee exoskeleton type of prosthesis.

  20. Prosthetic heart valve evaluation by magnetic resonance imaging

    OpenAIRE

    Hasenkam, J. Michael; Ringgaard, Steffen; Houlind, Kim; Botnar, René M.; Stødkilde-Jørgensen, Hans; Boesiger, Peter; Pedersen, Erik Morre

    2017-01-01

    Objective: To evaluate the potential of magnetic resonance imaging (MRI) for evaluation of velocity fields downstream of prosthetic aortic valves. Furthermore, to provide comparative data from bileaflet aortic valve prostheses in vitro and in patients. Methods: A pulsatile flow loop was set up in a 7.0 Tesla MRI scanner to study fluid velocity data downstream of a 25 mm aortic bileaflet heart valve prosthesis. Three dimensional surface plots of velocity fields were displayed. In six NYHA clas...

  1. The effect of platelet-rich plasma on composite graft survival.

    Science.gov (United States)

    Jeon, Yeo Reum; Kang, Eun Hye; Yang, Chae Eun; Yun, In Sik; Lee, Won Jai; Lew, Dae Hyun

    2014-08-01

    Composite grafts are suitable for facial reconstruction because of good color matching, low donor-site morbidity, acceptable texture, and easy surgical techniques. However, their use is limited to small defects and by unpredictable survival rates. As platelet-rich plasma contains large numbers of growth factors and has been widely used for tissue regeneration, this study aimed to investigate platelet-rich plasma as an adjuvant to enhance composite graft survival. Twenty New Zealand White rabbits were used, and chondrocutaneous composite grafts were applied to their ears. The grafts were then returned to their original positions after rotation to block the original circulation from the base of the graft. Each of the individual ears was assigned randomly into one of two groups: experimental (n=20; platelet-rich plasma group) or control (n=20; control group). The surrounding skin of the composite graft was injected with either 1.0 ml of platelet-rich plasma derived from autologous whole blood in the platelet-rich plasma group or normal saline in the control group. Graft survival, cutaneous blood flow, CD31-stained vessels, and vascular endothelial growth factor protein levels were examined. Twelve days after surgery, graft viability in the platelet-rich plasma group was higher than in the control group. Blood perfusion was also higher in the platelet-rich plasma group. Compared with the control group, the number of CD31 blood vessels and vascular endothelial growth factor expression levels were significantly increased in the platelet-rich plasma group. The authors' results suggest that platelet-rich plasma restores the perfusion of composite grafts by enhancing revascularization and may exert therapeutic effects on the survival of composite grafts.

  2. A smartphone photogrammetry method for digitizing prosthetic socket interiors.

    Science.gov (United States)

    Hernandez, Amaia; Lemaire, Edward

    2017-04-01

    Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficulties arise when working from the person's socket since current 3D scanners have difficulties scanning socket interiors. While dedicated scanners exist, they are expensive and the cost may be prohibitive for a limited number of scans per year. A low-cost and accessible photogrammetry method for socket interior digitization is proposed, using a smartphone camera and cloud-based photogrammetry services. 15 two-dimensional images of the socket's interior are captured using a smartphone camera. A 3D model is generated using cloud-based software. Linear measurements were comparing between sockets and the related 3D models. 3D reconstruction accuracy averaged 2.6 ± 2.0 mm and 0.086 ± 0.078 L, which was less accurate than models obtained by high quality 3D scanners. However, this method would provide a viable 3D digital socket reproduction that is accessible and low-cost, after processing in prosthetic CAD software. Clinical relevance The described method provides a low-cost and accessible means to digitize a socket interior for use in prosthetic CAD/CAM systems, employing a smartphone camera and cloud-based photogrammetry software.

  3. Orientation and mobility assessment in retinal prosthetic clinical trials.

    Science.gov (United States)

    Geruschat, Duane R; Bittner, Ava K; Dagnelie, Gislin

    2012-09-01

    The purpose of this study was to develop an orientation and mobility (O&M) assessment protocol to implement in subjects who have been implanted with an artificial silicon retina (ASR), and to use this experience to propose a research agenda for O&M with prosthetic vision. A controlled and naturalistic assessment was developed that included walking a prescribed obstacle course and travel to and from a hospital cafeteria. Subjects were tested before and 3 and 6 months after being implanted with the ASR. Outcome measures were walking speed and number of contacts with obstacles. The experiences from this study led to a proposed research agenda in O&M. Eight subjects with retinitis pigmentosa participated in this study. The vision status of the subjects ranged from mobility after implantation. Three subjects self-reported enhancements of travel after implantation, but this enhancement was not observed. This study demonstrates that mobility might not be improved with prosthetic vision. The proposed research agenda emphasizes the importance of developing individualized assessments, identifying specific items of orientation rather than mobility for measuring the effect of prosthetic vision, and to develop and evaluate instructional programs that may be needed to obtain the full benefit of the technology.

  4. Development of Standardized Material Testing Protocols for Prosthetic Liners.

    Science.gov (United States)

    Cagle, John C; Reinhall, Per G; Hafner, Brian J; Sanders, Joan E

    2017-04-01

    A set of protocols was created to characterize prosthetic liners across six clinically relevant material properties. Properties included compressive elasticity, shear elasticity, tensile elasticity, volumetric elasticity, coefficient of friction (CoF), and thermal conductivity. Eighteen prosthetic liners representing the diverse range of commercial products were evaluated to create test procedures that maximized repeatability, minimized error, and provided clinically meaningful results. Shear and tensile elasticity test designs were augmented with finite element analysis (FEA) to optimize specimen geometries. Results showed that because of the wide range of available liner products, the compressive elasticity and tensile elasticity tests required two test maxima; samples were tested until they met either a strain-based or a stress-based maximum, whichever was reached first. The shear and tensile elasticity tests required that no cyclic conditioning be conducted because of limited endurance of the mounting adhesive with some liner materials. The coefficient of friction test was based on dynamic coefficient of friction, as it proved to be a more reliable measurement than static coefficient of friction. The volumetric elasticity test required that air be released beneath samples in the test chamber before testing. The thermal conductivity test best reflected the clinical environment when thermal grease was omitted and when liner samples were placed under pressure consistent with load bearing conditions. The developed procedures provide a standardized approach for evaluating liner products in the prosthetics industry. Test results can be used to improve clinical selection of liners for individual patients and guide development of new liner products.

  5. Ergonomic workplace assessment in orthotic and prosthetic workshops.

    Science.gov (United States)

    Salmani Nodooshan, H; Koohi Booshehri, S; Daneshmandi, H; Choobineh, A R

    2016-10-17

    In Iranian orthotic and prosthetic workshops, the majority of activities are carried out by manpower and the tasks are labor-intensive. In these workshops, ergonomic aspects of working conditions are seldom considered. This study was conducted in orthotic and prosthetic workshops with the objectives of determination of prevalence rate of MSDs among employees and assessment of ergonomics working conditions. In this cross-sectional study, all employees (n = 42; 29 males and 13 females) in 11 active orthotic and prosthetic production centers of Shiraz city participated. Data were collected using Nordic Musculoskeletal disorders Questionnaire (NMQ) and observational technique by an ergonomics checklist for assessment of working conditions. The means (SD) of age and job tenure (years) in the study individuals were 37.26 (10.21) and 12.8 (9.39), respectively. The most prevalent MSD symptoms in the past 12 months were reported in the lower back (42.9%), shoulders (40.5%) and knees (40.5%). Working conditions assessment showed that the main ergonomic problems in the workshops studied originated from awkward working posture, improper workstation design, poorly designed hand tools and incorrect manual material handling. Any interventional program for working conditions improvement should, therefore, focus on these areas.

  6. Prosthetic design directives: Low-cost hands within reach.

    Science.gov (United States)

    Jones, G K; Rosendo, A; Stopforth, R

    2017-07-01

    Although three million people around the world suffer from the lack of one or both upper limbs 80% of this number is located within developing countries. While prosthetic prices soar with technology 3D printing and low cost electronics present a sensible solution for those that cannot afford expensive prosthetics. The electronic and control design of a low-cost prosthetic hand, the Touch Hand II, is discussed. This paper shows that sensorless techniques can be used to reduce design complexities, costs, and provide easier access to the electronics. A closing and opening finite state machine (COFSM) was developed to handle the actuated digit joint control state and a supervisory switching control scheme, used for speed and grip strength control. Three torque and speed settings were created to be preset for specific grasps. The hand was able to replicate ten frequently used grasps and grip some common objects. Future work is necessary to enable a user to control it with myoelectric signals (MESs) and to solve operational problems related to electromagnetic interference (EMI).

  7. Iodine-125 orbital brachytherapy with a prosthetic implant in situ

    Energy Technology Data Exchange (ETDEWEB)

    Stannard, Clare [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Radiation Oncology; Maree, Gert; Munro, Roger [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Medical Physics; Lecuona, Karin [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Ophthalmology; Sauerwein, Wolfgang [Universitaetsklinikum Essen (Germany). Strahlenklinik, NCTeam

    2011-05-15

    Purpose: Brachytherapy is one method of irradiating the orbit after enucleation of an eye with a malignant tumor that has a potential to recur. It consists of 6 trains of I-125 seeds placed around the periphery of the orbit, a shorter central train, and a metal disc, loaded with seeds, placed beneath the eyelids. The presence of a prosthetic orbital implant requires omission of the central train and adjustment of the activity of the seeds in the anterior orbit around the prosthesis. Patients and Methods: This is a retrospective review of the technical modifications and outcome of 12 patients treated in this manner: 6 with retinoblastoma, 5 with malignant melanoma, and 1 with an intraocular rhabdomyosarcoma. The median dose was 35.5 Gy in 73 hours for retinoblastoma and 56 Gy in 141 hours for malignant melanoma. Patients with retinoblastoma and rhabdomyosarcoma also received chemotherapy. Results: The tubes can be placed satisfactorily around the prosthesis. The increased activity in the anterior half of the tubes produced comparable dose distributions. There have been no orbital recurrences, no extrusion of the prosthesis, and cosmesis is good. Conclusion: Insertion of a prosthetic implant at the time of enucleation greatly enhances the subsequent cosmetic appearance. This should be encouraged unless there is frank tumor in the orbit. Orbital brachytherapy without the central train continues to give excellent local control. The short treatment time and good cosmesis are added advantages. The patient is spared the expense and inconvenience of removing and replacing the prosthetic implant. (orig.)

  8. Novel implant for peri-prosthetic proximal tibia fractures.

    Science.gov (United States)

    Tran, Ton; Chen, Bernard K; Wu, Xinhua; Pun, Chung Lun

    2018-02-02

    Repair of peri-prosthetic proximal tibia fractures is very challenging in patients with a total knee replacement or arthroplasty. The tibial component of the knee implant severely restricts the fixation points of the tibial implant to repair peri-prosthetic fractures. A novel implant has been designed with an extended flange over the anterior of tibial condyle to provide additional points of fixation, overcoming limitations of existing generic locking plates used for proximal tibia fractures. Furthermore, the screws fixed through the extended flange provide additional support to prevent the problem of subsidence of tibial component of knee implant. The design methodology involved extraction of bone data from CT scans into a flexible CAD format, implant design and structural evaluation and optimisation using FEM as well as prototype development and manufacture by selective laser melting 3D printing technology with Ti6Al4 V powder. A prototype tibia implant was developed based on a patient-specific bone structure, which was regenerated from the CT images of patient's tibia. The design is described in detail and being applied to fit up to 80% of patients, for both left and right sides based on the average dimensions and shape of the bone structure from a wide range of CT images. A novel tibial implant has been developed to repair peri-prosthetic proximal tibia fractures which overcomes significant constraints from the tibial component of existing knee implant. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Dynamics of bone graft healing around implants

    Directory of Open Access Journals (Sweden)

    Narayan Venkataraman

    2015-01-01

    A few questions arise pertaining to the use of bone grafts along with implants are whether these are successful in approximation with implant. Do they accelerate bone regeneration? Are all defects ultimately regenerated with new viable bone? Is the bone graft completely resorbed or integrated in new bone? Does the implant surface characteristic positively affect osseointegration when used with a bone graft? What type of graft and implant surface can be used that will have a positive effect on the healing type and time? Finally, what are the dynamics of bone graft healing around an implant? This review discusses the cellular and molecular mechanisms of bone graft healing in general and in vicinity of another foreign, avascular body, namely the implant surface, and further, the role of bone grafts in osseointegration and/or clinical success of the implants.

  10. [Pre-prosthetics: role of the physiotherapist in the treatment of the residual limb and prosthetic preparation of the person].

    Science.gov (United States)

    Maffi, Alberto; Mulè, Chiara; Taveggia, Giovanni

    2015-01-01

    The rehabilitation of amputees requires a multi-discipline approach. Within the work of the team, physiotherapy plays a central role both in terms of the technical skills made available to the patient, as well as in terms of the psychological-motivational support offered to the amputee during treatment. The pre-prosthetic phase of rehabilitation is the beginning of a complex rehabilitative process during which starts with an assessment of the general clinical condition of the patient and their residual capacities, so as to develop personalised rehabilitative strategies based upon the needs of the amputee. This whole process aims to get the amputee standing with a prosthetic as quickly as possible, thus allowing the social reintegration of the amputee.

  11. Short-term alendronate treatment does not maintain a residual effect on spinal fusion with interbody devices and bone graft after treatment withdrawal: an experimental study on spinal fusion in pigs.

    Science.gov (United States)

    Huang, Baoding; Zou, Xuenong; Li, Haisheng; Xue, Qingyun; Bünger, Cody

    2013-02-01

    Whether alendronate treatment has a residual effect on bone ingrowth into porous biomaterial in humans or experimental animals after treatment withdrawal is still unknown. The purpose of this study was to investigate bone ingrowth into porous tantalum and carbon fiber interbody implants after discontinuing alendronate treatment in experimental spinal fusion in pigs. Twenty-four pigs were randomly divided into two groups of each 12 pigs. The pigs underwent anterior intervertebral lumbar arthrodeses at L2-3, L4-5 and L6-7. Each level was randomly allocated to one of the three implants: a porous tantalum ring with pedicle screw fixation, a porous tantalum ring or a carbon fiber cage with anterior staple fixation. The central hole of implants was packed with an autograft. Alendronate was given orally for the first 3 months to one of the two groups. The pigs were observed for 6 months postoperatively. Histology and micro-CT scans were done at the endpoint. The spinal fusion rates of each implant showed no differences between two treatment groups. Furthermore, no differences were found between two groups as for bone ingrowth into the central holes of implants and bone-implant interface in each implant, or as for the pores of tantalum implants. Trabecular bone microarchitecture in the central hole of the carbon fiber cage did not differ between two treatment groups. The application of ALN, with a dose equivalent to that given to humans during the first 3 months after surgery, does not maintain a residual effect on spinal fusion with porous tantalum ring and autograft after treatment withdrawal in a porcine ALIF model.

  12. Advances in Retinal Prosthetic Research: A Systematic Review of Engineering and Clinical Characteristics of Current Prosthetic Initiatives.

    Science.gov (United States)

    Cheng, Derrick L; Greenberg, Paul B; Borton, David A

    2017-03-01

    To date, reviews of retinal prostheses have focused primarily on devices undergoing human trials in the Western Hemisphere and fail to capture significant advances in materials and engineering research in countries such as Japan and Korea, as well as projects in early stages of development. To address these gaps, this systematic review examines worldwide advances in retinal prosthetic research, evaluates engineering characteristics and clinical progress of contemporary device initiatives, and identifies potential directions for future research in the field of retinal prosthetics. A literature search using PubMed, Google Scholar, and IEEExplore was conducted following the PRISMA Guidelines for Systematic Review. Inclusion criteria were peer-reviewed papers demonstrating progress in human or animal trials and papers discussing the prosthetic engineering design. For each initiative, a description of the device, its engineering considerations, and recent clinical results were provided. Ten prosthetic initiatives met our inclusion criteria and were organized by stimulation location. Of these initiatives, four have recently completed human trials, three are undergoing multi- or single-center human trials, and three are undergoing preclinical animal testing. Only the Argus II (FDA 2013, CE 2011) has obtained FDA approval for use in the United States; the Alpha-IMS (CE 2013) has achieved the highest visual acuity using a Landolt-C test to date and is the only device presently undergoing a multicenter clinical trial. Several distinct approaches to retinal stimulation have been successful in eliciting visual precepts in animals and/or humans. However, many clinical needs are still not met and engineering challenges must be addressed before a retinal prosthesis with the capability to fully and safely restore functional vision can be realized.

  13. A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations

    Science.gov (United States)

    2017-09-01

    commercial prosthetic feet is the limited number and diversity of feet included in studies relative to those available on the market . Given that there are...the Department of Defense ( study sponsors) Other federal agencies including, but not limited to, the Food and Drug Administration (FDA), the Office for...STATEMENT Approved for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The objective of this study is to evaluate a “test

  14. Risks and Challenges of Surgery for Aortic Prosthetic Valve Endocarditis.

    Science.gov (United States)

    Grubitzsch, Herko; Tarar, Waharat; Claus, Benjamin; Gabbieri, Davide; Falk, Volkmar; Christ, Torsten

    2018-03-01

    Prosthetic valve endocarditis is the most severe form of infective endocarditis. This study assessed the risks and challenges of surgery for aortic prosthetic valve endocarditis. In total, 116 consecutive patients (98 males, age 65.2±12.7years), who underwent redo-surgery for active aortic prosthetic valve endocarditis between 2000 and 2014, were reviewed. Cox regression analysis was used to identify factors for aortic root destructions as well as for morbidity and mortality. Median follow-up was 3.8 years (0-13.9 years). Aortic root destructions (42 limited and 29 multiple lesions) were associated with early prosthetic valve endocarditis and delayed diagnosis (≥14 d), but not with mortality. There were 16 (13.8%) early (≤30 d) and 32 (27.6%) late (>30 days) deaths. Survival at 1, 5, and 10 years was 72±4.3%, 56±5.4%, and 46±6.4%, respectively. The cumulative incidence of death, reinfection, and reoperation was 19.0% at 30days and 36.2% at 1year. Delayed diagnosis, concomitant procedures, and EuroSCORE II >20% were predictors for early mortality and need for mechanical circulatory support, age >70years, and critical preoperative state were predictors for late mortality. In their absence, survival at 10 years was 70±8.4%. Reinfections and reoperations occurred more frequently if ≥1 risk factor for endocarditis and aortic root destructions were present. At 10 years, freedom from reinfection and reoperation was 89±4.2% and 91±4.0%. The risks of death, reinfection, and reoperation are significant within the first year after surgery for aortic prosthetic valve endocarditis. Early diagnosis and aortic root destructions are the most important challenges, but advanced age, critical preoperative state, and the need for mechanical circulatory support determine long-term survival. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B

  15. Complete oral rehabilitation of a deep bite patient with Ewing’s sarcoma; surgical and prosthetic phases: A clinical report

    Directory of Open Access Journals (Sweden)

    Mehran Bahrami

    2017-01-01

    Full Text Available Introduction: Ewings sarcoma (ES is an unusual, aggressive malignant neoplasm occurring primarily in the long bones of the lower and upper extremities followed by pelvis, ribs, vertebrae, skull, and jaws-bones. Patients with ES tumor need long-term complete oral reconstruction. The location of the primary tumor in the face is predominantly in the mandible, and usually in the posterior mandible. Case Report: Here, both surgical procedures and prosthetic reconstruction in three stages of a 10-year-old childs life presented. Definitive prosthetic reconstruction is extremely challenging in such patients after previous excessive surgical resection, especially when the patient has complex dental abnormality. Fixed dental prostheses and implant-supported fixed restorations have been selected as the preferred treatment option in this case after increasing occlusal vertical dimension (OVD to create sufficient interocclusal space (IOS. Discussion: In this case, ES patient treated in three phases. In the first-stage, only surgical resection of tumor and bone graft reconstruction with titanium plate fixation was performed. In the second-stage, Lefort I surgery for maxilla with dental implants insertion in mandible was done simultaneously. For definitive restorations fabrication, it was mandatory to increase occlusal vertical dimension (OVD to create sufficient inter-occlusal space (IOS for the restorations. OVD has been altered to achieve more stable relationship of mandibular teeth with maxillary teeth, and to obtain an optimum esthetic and functional result. Several factors should be considered as determinants for increasing the OVD such as remaining tooth structure, the space available for the restorations such as the current situation, occlusal variables, and esthetics.

  16. Clinical Effectiveness of Using Aesthetic Fixed Prosthetic Appliances with Combined Occlusal Surface

    OpenAIRE

    Andrii Biben; Zinovii Ozhohan

    2017-01-01

    The objective of the research was to evaluate the clinical effectiveness of using aesthetic fixed prosthetic appliances with combined occlusal surface. Materials and methods. The study included 30 patients who were divided into 2 groups: Group I included 20 patients with combined occlusal surface of the crowns; Group II included 22 patients with ceramic occlusal surface of the crowns. The patients were observed 3, 6 and 12 months after prosthetic repair. Results. 6 months after prosthet...

  17. LOW-MOLECULAR-WEIGHT HEPARIN TREATMENT FAILURE IN PREVENTION OF PROSTHETIC MITRAL VALVE THROMBOSIS

    OpenAIRE

    David Šuran; Vojko Kanič; Tatjana Golob Gulič; Husam Franjo Naji; Robert Lipovec

    2009-01-01

    Background Prosthetic heart valve thrombosis (PHVT) represents a dangerous postoperative complication following prosthetic heart valve replacement. Incidence varies according to different data from 0.5–4 % per year following mitral or aortic valve replacement in spite of adequate oral anticoagulation with coumarins. Case report We are presenting a case of prosthetic mitral valve thrombosis as a result of 6-month lowmolecular-weight heparin (LMWH) (nadroparine) treatment failure. Our pat...

  18. Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health

    OpenAIRE

    Wernke, Matthew M.; Schroeder, Ryan M.; Haynes, Michael L.; Nolt, Lonnie L.; Albury, Alexander W.; Colvin, James M.

    2017-01-01

    Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to ea...

  19. The Efficacy of Fish Scales as Bone Graft Alternative Materials

    Directory of Open Access Journals (Sweden)

    Abdul Gani Soulissa

    2018-01-01

    Full Text Available Background: Bone graft application is a therapy that could be used to repair bone and minimize bone resorption. However, current bone graft materials carry risks for the recipient. Studies on alloplast, which can be found in fish bones and scales have been developed in the past few years. Objectives: This study aimed to determine the efficacy of hydroxyapatite powder from white barramundi (Lates calcarifer fish scales as bone graft material in the mandibular defect regeneration of rats. Methods: This experimental laboratory study utilized 24 male Sprague-Dawley rats aged 16 weeks as test subjects, where 12 were used for control groups and the other 12 were used as the experimental group. All were given bone defects of 3 mm on the right mandible, split into 6 groups of 4 (3 experimental and 3 control groups, and the groups were observed for 2, 4, and 6 weeks respectively. The surgery results were assessed by radiography and histopathologic analysis. Result: Radiography results showed that the highest bone growth was found in the 6 weeks treatment group with 100% growth, followed by the 4 weeks treatment group with 88.89% growth, and last was the 2 weeks treatment group with 66.67% growth. The Mann-Whitney test showed that there is a significant difference between pre- and post-intervention (p-value=0.026. Histopathologic analysis showed the presence of osteocytes and osteoblasts in the 6 weeks treatment group. Conclusion: It can be concluded that hydroxyapatite powder from white barramundi fish scales can be used as a bone graft alternative material.

  20. Septal graft in laryngeal reconstruction

    International Nuclear Information System (INIS)

    Bahannan, Abdulrahman; Slavicek, A.; Taudy, M.; Chovanec, M.

    2006-01-01

    A 62-year-old woman presented with symptoms of dyspnea. Ultrasonography and computed tomography examinations revealed mass extending from the cricoid cartilage to the left lobe of thyroid gland and thyroid cartilage. Cytology revealed possibility of cartilaginous origin, which was proven to be chondrosarcoma (Grade 1) from the biopsy specimen obtained during panendosopy. She underwent one stage radical resection and immediate reconstruction of laryngeal skeleton defect by mucocartilaginous graft from the nasal septum. Her postoperative course was optimal with preservation of the laryngeal functions. Twenty-eight months postoperatively, she had to undergo total laryngectomy as a salvage procedure for the advanced local recurrence. We report on the relatively easy technique for functional reconstruction of the large laryngeal defect with the employment cartilage graft from the nasal septum. (author)