Progress Toward Development of a Multichannel Vestibular Prosthesis for Treatment of Bilateral Vestibular Deficiency

Science.gov (United States)

FRIDMAN, GENE Y.; DELLA SANTINA, CHARLES C.

2014-01-01

This article reviews vestibular pathology and the requirements and progress made in the design and construction of a vestibular prosthesis. Bilateral loss of vestibular sensation is disabling. When vestibular hair cells are injured by ototoxic medications or other insults to the labyrinth, the resulting loss of sensory input disrupts vestibulo-ocular reflexes (VORs) and vestibulo-spinal reflexes that normally stabilize the eyes and body. Affected individuals suffer poor vision during head movement, postural instability, chronic disequilibrium, and cognitive distraction. Although most individuals with residual sensation compensate for their loss over time, others fail to do so and have no adequate treatment options. A vestibular prosthesis analogous to cochlear implants but designed to modulate vestibular nerve activity during head movement should improve quality of life for these chronically dizzy individuals. We describe the impact of bilateral loss of vestibular sensation, animal studies supporting feasibility of prosthetic vestibular stimulation, the current status of multichannel vestibular sensory replacement prosthesis development, and challenges to successfully realizing this approach in clinical practice. In bilaterally vestibular-deficient rodents and rhesus monkeys, the Johns Hopkins multichannel vestibular prosthesis (MVP) partially restores the three-dimensional (3D) VOR for head rotations about any axis. Attempts at prosthetic vestibular stimulation of humans have not yet included the 3D eye movement assays necessary to accurately evaluate VOR alignment, but these initial forays have revealed responses that are otherwise comparable to observations in animals. Current efforts now focus on refining electrode design and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimizing stimulus protocols to improve dynamic range and reduce excitation–inhibition asymmetry, and adapting laboratory MVP prototypes into devices

Progress toward development of a multichannel vestibular prosthesis for treatment of bilateral vestibular deficiency.

Science.gov (United States)

Fridman, Gene Y; Della Santina, Charles C

2012-11-01

This article reviews vestibular pathology and the requirements and progress made in the design and construction of a vestibular prosthesis. Bilateral loss of vestibular sensation is disabling. When vestibular hair cells are injured by ototoxic medications or other insults to the labyrinth, the resulting loss of sensory input disrupts vestibulo-ocular reflexes (VORs) and vestibulo-spinal reflexes that normally stabilize the eyes and body. Affected individuals suffer poor vision during head movement, postural instability, chronic disequilibrium, and cognitive distraction. Although most individuals with residual sensation compensate for their loss over time, others fail to do so and have no adequate treatment options. A vestibular prosthesis analogous to cochlear implants but designed to modulate vestibular nerve activity during head movement should improve quality of life for these chronically dizzy individuals. We describe the impact of bilateral loss of vestibular sensation, animal studies supporting feasibility of prosthetic vestibular stimulation, the current status of multichannel vestibular sensory replacement prosthesis development, and challenges to successfully realizing this approach in clinical practice. In bilaterally vestibular-deficient rodents and rhesus monkeys, the Johns Hopkins multichannel vestibular prosthesis (MVP) partially restores the three-dimensional (3D) VOR for head rotations about any axis. Attempts at prosthetic vestibular stimulation of humans have not yet included the 3D eye movement assays necessary to accurately evaluate VOR alignment, but these initial forays have revealed responses that are otherwise comparable to observations in animals. Current efforts now focus on refining electrode design and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimizing stimulus protocols to improve dynamic range and reduce excitation-inhibition asymmetry, and adapting laboratory MVP prototypes into devices

EFNS guidelines on neurostimulation therapy for neuropathic pain

DEFF Research Database (Denmark)

EFNS Panel on Neuropathic Pain, Vienna; Cruccu, Giorgio; Aziz, T. Z.

2007-01-01

and to produce relevant recommendations. We searched the literature from 1968 to 2006, looking for neurostimulation in neuropathic pain conditions, and classified the trials according to the EFNS scheme of evidence for therapeutic interventions. Spinal cord stimulation (SCS) is efficacious in failed back surgery......Pharmacological relief of neuropathic pain is often insufficient. Electrical neurostimulation is efficacious in chronic neuropathic pain and other neurological diseases. European Federation of Neurological Societies (EFNS) launched a Task Force to evaluate the evidence for these techniques......TMS) has transient efficacy in central and peripheral neuropathic pains (level B). Motor cortex stimulation (MCS) is efficacious in central post-stroke and facial pain (level C). Deep brain stimulation (DBS) should only be performed in experienced centres. Evidence for implanted peripheral stimulations...

Critical review of the responsive neurostimulator system for epilepsy

Directory of Open Access Journals (Sweden)

Thomas GP

2015-10-01

Full Text Available George P Thomas, Barbara C Jobst Dartmouth-Hitchcock Medical Center, Geisel School of Medicine, Dartmouth College, Lebanon, NH, USA Abstract: Patients with medically refractory epilepsy have historically had few effective treatment options. Electrical brain stimulation for seizures has been studied for decades and ongoing technological refinements have made possible the development of an implantable electrical brain stimulator. The NeuroPace responsive neurostimulator was recently approved by the FDA for clinical use and the initial reports are encouraging. This device continually monitors brain activity and delivers an electric stimulus when abnormal activity is detected. Early reports of efficacy suggest that the device is well tolerated and offers a reduction in seizure frequency by approximately half at 2 years. Keywords: medically refractory epilepsy, seizures, brain surgery, brain stimulation, neurostimulation

Mitigating bit flips or single event upsets in epilepsy neurostimulators

Directory of Open Access Journals (Sweden)

Alice X. Dong

2016-01-01

Conclusions: Cosmic radiation can threaten RAM and settings of neurostimulators; neuromodulation teams and device designers need to take this threat into account when designing multifunctional neuromodulation systems.

Intermittent, noncyclic dysfunction of a mechanical aortic prosthesis by pannus formation.

Science.gov (United States)

Giroux, Sylvie K; Labinaz, Marino X; Grisoli, Dominique; Klug, Andrew P; Veinot, John P; Burwash, Ian G

2010-01-01

Mechanical aortic prosthesis dysfunction can result from thrombosis or pannus formation. Pannus formation usually restricts systolic excursion of the occluding disk, resulting in progressive stenosis of the aortic prosthesis. Intermittent dysfunction of a mechanical aortic prosthesis is usually ascribed to thrombus formation. We describe an unusual case of intermittent, noncyclic dysfunction of a mechanical aortic prosthesis due to pannus formation in the absence of systolic restriction of disk excursion that presented with intermittent massive aortic regurgitation, severe ischemia, and shock. Pannus formation should be considered as a potential cause of acute intermittent severe aortic regurgitation in a patient with a mechanical aortic prosthesis.

Current views on neurostimulation in the treatment of cardiac ischemic syndromes.

Science.gov (United States)

Jessurun, G A; DeJongste, M J; Blanksma, P K

1996-08-01

Most clinicians are still unacquainted with the beneficial effects of neurostimulation as an additional therapeutic strategy for severe angina pectoris. Patients with therapeutically refractory angina pectoris suffer from chest discomfort during minimal exercise, despite maximal tolerated antianginal drug therapy (at least 2 out of a beta-blocker, calcium-antagonist or long-acting nitrate). In these patients, revascularization procedures, such as a percutaneous transluminal coronary angioplasty or coronary artery bypass surgery, are often technically impossible because of diffuse coronary artery disease or should be withheld as a consequence of absolute contraindications such as severe left ventricular dysfunction. All patients have inoperable multivessel disease, experienced one or more myocardial infarctions, and were treated by earlier invasive interventions. This group of patients are severely physically and psychologically disabled by their intractable angina pectoris. Available published data and the neurostimulation experience of the authors are reviewed in relation to the treatment of cardiac ischemic syndromes. We conclude that neurostimulation is an effective therapeutic adjuvant for patients with severe angina pectoris unresponsive to standard treatment. This treatment modality appears to be safe, and a promising tool for other ischemic cardiac syndromes.

Laser-assisted fixation of a nitinol stapes prosthesis.

Science.gov (United States)

Schrötzlmair, Florian; Suchan, Fabian; Pongratz, Thomas; Krause, Eike; Müller, Joachim; Sroka, Ronald

2018-02-01

Otosclerosis is an inner ear bone disease characterized by fixation of the stapes and consequently progressive hearing loss. One treatment option is the surgical replacement of the stapes by a prosthesis. When so called "smart materials" like nitinol are used, prosthesis fixation can be performed using a laser without manual crimping on the incus. However, specific laser-prosthesis interactions have not been described yet. The aim of the present study was to elucidate the thermo-mechanical properties of the NiTiBOND® prosthesis as a basis for handling instructions for laser-assisted prosthesis fixation. Closure of the NiTiBOND® prosthesis was induced ex vivo by either a diode laser emitting at λ = 940 nm or a CO 2 laser (λ = 10,600 nm). Total energy for closure was determined. Suitable laser parameters (pulse duration, power per pulse, distance between tip of the laser fiber and prosthesis) were assessed. Specific laser-prosthesis interactions were recorded. Especially the diode laser was found to be an appropriate energy source. A total energy deposit of 60 mJ by pulses in near contact application was found to be sufficient for prosthesis closure ex vivo. Energy should be transmitted through a laser fiber equipollent to the prosthesis band diameter. Specific deformation characteristics due to the zonal prosthesis composition have to be taken into account. NiTiBOND® stapes prosthesis can be closed by very little energy when appropriate energy sources like diode lasers are used, suggesting a relatively safe application in vivo. Lasers Surg. Med. 50:153-157, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Quantitative cognitive-test characterization of reconnectable implantable fiber-optic neurointerfaces for optogenetic neurostimulation.

Science.gov (United States)

Fedotov, I V; Ivashkina, O I; Pochechuev, M S; Roshchina, M A; Toropova, K A; Fedotov, A B; Anokhin, K V; Zheltikov, A M

2017-11-01

Cognitive tests on representative groups of freely behaving transgenic mice are shown to enable a quantitative characterization of reconnectable implantable fiber-optic neurointerfaces for optogenetic neurostimulation. A systematic analysis of such tests provides a robust quantitative measure for the cognitive effects induced by fiber-optic neurostimulation, validating the performance of fiber-optic neurointerfaces for long-term optogenetic brain stimulations and showing no statistically significant artifacts in the behavior of transgenic mice due to interface implantation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spinal epidural neurostimulation for treatment of acute and chronic intractable pain: initial and long term results.

Science.gov (United States)

Richardson, R R; Siqueira, E B; Cerullo, L J

1979-09-01

Spinal epidural neurostimulation, which evolved from dorsal column stimulation, has been found to be effective in the treatment of acute and chronic intractable pain. Urban and Hashold have shown that it is a safe, simplified alternative to dorsal column stimulation, especially because laminectomy is not required if the electrodes are inserted percutaneously. Percutaneous epidural neurostimulation is also advantageous because there can be a diagnostic trial period before permanent internalization and implantation. This diagnostic and therapeutic modality has been used in 36 patients during the past 3 years at Northwestern Memorial Hospital. Eleven of these patients had acute intractable pain, which was defined as pain of less than 1 year in duration. Initial postimplantation results from the 36 patients indicate that spinal epidural neurostimulation is most effective in treating the intractable pain of diabetes, arachnoiditis, and post-traumatic and postamputation neuroma. Long term follow-up, varying from 1 year to 3 years postimplantation in the 20 initially responding patients, indicates that the neurostimulation continues to provide significant pain relief (50% or greater) in a majority of the patients who experienced initial significant pain relief.

Transcutaneous electrical neurostimulation in musculoskeletal pain of acute spinal cord injuries.

Science.gov (United States)

Richardson, R R; Meyer, P R; Cerullo, L J

1980-01-01

Cervical, thoracic, thoracolumbar, and lumbar fractures associated with physiologic complete or incomplete spinal cord injuries frequently have severe soft-tissue injury as well as severe pain associated with the site or area of injury. Transcutaneous electrical neurostimulation has proved effective in the treatment of various causes of severe acute and chronic intractable pains. We applied this modality to a group of 20 patients who had acute spinal cord injuries and pain associated with severe, extensive soft-tissue injury. Its advantages include ease of application, lack of major complications, increased intestinal peristalsis, and avoidance of narcotic analgesic medications. It also produced significant (greater than 50%) pain relief in 75% of patients treated by transcutaneous electrical neurostimulation.

Life Estimation of Hip Joint Prosthesis

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Desai, C.; Hirani, H.; Chawla, A.

2015-07-01

Hip joint is one of the largest weight-bearing structures in the human body. In the event of a failure of the natural hip joint, it is replaced with an artificial hip joint, known as hip joint prosthesis. The design of hip joint prosthesis must be such so as to resist fatigue failure of hip joint stem as well as bone cement, and minimize wear caused by sliding present between its head and socket. In the present paper an attempt is made to consider both fatigue and wear effects simultaneously in estimating functional-life of the hip joint prosthesis. The finite element modeling of hip joint prosthesis using HyperMesh™ (version 9) has been reported. The static analysis (load due to the dead weight of the body) and dynamic analysis (load due to walking cycle) have been described. Fatigue life is estimated by using the S-N curve of individual materials. To account for progressive wear of hip joint prosthesis, Archard's wear law, modifications in socket geometry and dynamic analysis have been used in a sequential manner. Using such sequential programming reduction in peak stress has been observed with increase in wear. Finally life is estimated on the basis of socket wear.

Restoration of bladder function in spastic neuropathic bladder using sacral deafferentation and different techniques of neurostimulation.

Science.gov (United States)

Schumacher, S; Bross, S; Scheepe, J R; Alken, P; Jünemann, K P

1999-01-01

Conventional sacral anterior root stimulation (SARS) results in simultaneous activation of both the detrusor muscle and the external urethral sphincter. We evaluated the possibilities of different neurostimulation techniques to overcome stimulation induced detrusor-sphincter-dyssynergia and to achieve a physiological voiding. The literature was reviewed on different techniques of sacral anterior root stimulation of the bladder and the significance of posterior rhizotomy in patients with supraconal spinal cord injury suffering from the loss of voluntary bladder control, detrusor hyperreflexia and sphincter spasm. The achievement of selective detrusor activation would improve current sacral neurostimulation of the bladder, including the principle of "poststimulus voiding". This is possible with the application of selective neurostimulation in techniques of anodal block, high frequency block, depolarizing prepulses and cold block. Nowadays, sacral deafferentation is a standard therapy in combination with neurostimulation of the bladder because in conclusion advantages of complete rhizotomy predominate. The combination of sacral anterior root stimulation and sacral deafferentation is a successful procedure for restoration of bladder function in patients with supraconal spinal cord injury. Anodal block technique and cryotechnique are excellent methods for selective bladder activation to avoid detrusor-sphincter-dyssynergia and thus improve stimulation induced voiding.

Autonomic hyper-reflexia modulated by percutaneous epidural neurostimulation: a preliminary report.

Science.gov (United States)

Richardson, R R; Cerullo, L J; Meyer, P R

1979-06-01

Our clinical experience in the management of five paraplegic or quadriplegic patients with subjective complaints and objective findings of autonomic hyper-reflexia is presented. These five patients had epidural neurostimulation systems implanted percutaneously to regulate intractable spasticity. During a follow-up period varying from 2 months to almost 2 years, four of the five patients experienced no episodes of autonomic dysfunction with the use of a low frequency, low voltage, square wave pulse output. From their responses and from recent neurophysiological evidence, the potential benefit of percutaneous epidural neurostimulation in the modulation of autonomic hyper-reflexia without antihypertensive medication is suggested. Further follow-up of these patients and additional clinical research should be performed to confirm our initial clinical impressions.

Transcutaneous sacral neurostimulation for irritative voiding dysfunction.

Science.gov (United States)

Walsh, I K; Johnston, R S; Keane, P F

1999-01-01

Patients with irritative voiding dysfunction are often unresponsive to standard clinical treatment. We evaluated the response of such individuals to transcutaneous electrical stimulation of the third sacral nerve. 32 patients with refractory irritative voiding dysfunction (31 female and 1 male; mean age 47 years) were recruited to the study. Ambulatory transcutaneous electrical neurostimulation was applied bilaterally to the third sacral dermatomes for 1 week. Symptoms of frequency, nocturia, urgency, and bladder pain were scored by each patient throughout and up to 6 months following treatment. The mean daytime frequency was reduced from 11.3 to 7.96 (p = 0.01). Nocturia episodes were reduced from a mean of 2.6 to 1.8 (p = 0.01). Urgency and bladder pain mean symptom scores were reduced from 5.97 to 4.89 and from 1.48 to 0.64, respectively. After stopping therapy, symptoms returned to pretreatment levels within 2 weeks in 40% of the patients and within 6 months in 100%. Three patients who continued with neurostimulation remained satisfied with this treatment modality at 6 months. Transcutaneous third sacral nerve stimulation may be an effective and noninvasive ambulatory technique for the treatment of patients with refractory irritative voiding dysfunction. Following an initial response, patients may successfully apply this treatment themselves to ensure long-term relief.

Long-Term Experience with First-Generation Implantable Neurostimulation Device in Central Sleep Apnea Treatment.

Science.gov (United States)

Fox, Henrik; Bitter, Thomas; Horstkotte, Dieter; Oldenburg, Olaf; Gutleben, Klaus-Jürgen

2017-05-01

Sleep-disordered breathing (SDB) and Cheyne-Stokes respiration (CSR) are associated with shorter survival in patients with heart failure. A novel treatment method for this patient group is unilateral phrenic nerve stimulation by the remedē® system (Respicardia Inc., Minnetonka, MN, USA), a transvenously implantable neurostimulation device, which has recently been studied in a large randomized, controlled trial. Previous literature has shown efficacy and safety of the treatment with this first-generation device, but hardly any data are available on long-term clinical parameters, the remedē® device's battery lifetime, device exchangeability, lead position stability, surgical accessibility, and manageability. We performed remedē® device replacements in consecutive patients for battery depletion, and documented clinical parameters, longevity, operation procedure, complications, and difficulties. All patients were on neurostimulation treatment by phrenic nerve neurostimulation when device replacement became necessary. Apnea-hypopnea index (from 45 ± 4/h to 9 ± 4/h), oxygen-desaturation index (from 35 ± 7/h to 7 ± 6/h), and time spent with oxygen saturation of ray documentation of stable lead positions in a long-term setting, no radiation or contrast dye usage was needed and no major complications occurred. In addition, clinical exercise capacity and sleepiness symptoms improved. Novel remedē® device shows sustained therapy efficacy and safety in terms of stable lead positions over 4 years. Long-term phrenic nerve neurostimulation therapy for central SDB/CSR appears feasible in a clinical routine setting. © 2017 Wiley Periodicals, Inc.

Prosthesis infections after orthopedic joint replacement: the possible role of bacterial biofilms

Directory of Open Access Journals (Sweden)

Zhijun Song

2013-06-01

Full Text Available Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore, important to understand the comprehensive interaction between the microbiological situation and the host immune responses that lead to prosthesis infections. Evidence indicates that prosthesis infections are actually biofilm-correlated infections that are highly resistant to antibiotic treatment and the host immune responses. The authors reviewed the related literature in the context of their clinical experience, and discussed the possible etiology and mechanism leading to the infections, especially problems related to bacterial biofilm, and prophylaxis and treatment of infection, including both microbiological and surgical measures. Recent progress in research into bacterial biofilm and possible future treatment options of prosthesis-related infections are discussed.

Technical aspects of neurostimulation : focus on equipment, electric field modeling, and stimulation protocols

NARCIS (Netherlands)

Klooster, D.C.W.; de Louw, A.J.A.; Aldenkamp, A.P.; Besseling, R.M.H.; Mestrom, R.M.C.; Carrette, S.; Zinger, S.; Bergmans, J.W.M.; Mess, W.; Vonck, K.; Carrette, Evelien; Breuer, L.; Bernas, A.; Tijhuis, A.G.; Boon, P.

Neuromodulation is a field of science, medicine, and bioengineering that encompasses implantable and non-implantable technologies for the purpose of improving quality of life and functioning of humans. Brain neuromodulation involves different neurostimulation techniques: transcranial magnetic

[Interscalene block for total shoulder arthroplasty: comparative study (ultrasound vs. neurostimulation)].

Science.gov (United States)

Mejía-Terrazas, Gabriel Enrique; Ruiz-Suárez, Michell; Gaspar-Carrillo, Sandra Patricia; Valero-González, Fernando; Unzueta-Navarro, David; Encalada-Díaz, Iván

2014-01-01

Modern anesthesiology has integrated the use of ultrasonography as a tool that has displaced neurostimulation as a technique for locating peripheral nerves. The aim of this study was to determine which procedure is more effective for guiding interscalene block for total shoulder arthroplasty. We carried out a comparative, prospective non-randomized study comprised of the group guided by neurostimulation interscalene block and the group guided by ultrasound. All patients in both groups were scheduled for total shoulder arthroplasty. Latency, degree of sensory and motor block, success rate, postoperative pain intensity at 6, 12, and 24 h, patient satisfaction and complications were measured. We included 110 patients, 55 per group. Patients were placed in beach chair position and the deltopectoral approach was used. There were no differences in demographic characteristics. Results for neurostimulation vs. ultrasound group: latency 19.11 ± 2.27 vs. 17.24 ± 1.42 min, p= 0.23. Block sensitivity in both groups was grade 0 motor block grade 0 in 76.4% and grade 1 in 23.6% vs. grade 0 to 100%. There was 100% success rate for both groups. Postoperative pain at 6 h was 0.13 ± 0.54 vs. 0.11 ± 0.13 p= 0.90, at 12 h 1.67 ± 1.15 vs. 1.65 ± 0.59 p= 0.89 and at 24 h 3.15 ± 1.66 vs. 2.99 ± 1.15 p= 0.78. Satisfaction 54.5% very satisfied and 45.5% satisfied 96.36% vs 3.6% very satisfied and satisfied. Complications 18.18% vs. 3.6% p= 0.023. Ultrasound-guided interscalene nerve block is the technique of choice in elective total shoulder arthroplasty.

The influence of transcutaneous electrical neurostimulation (TENS) on human cerebral blood flow velocities

NARCIS (Netherlands)

ter Laan, Mark; van Dijk, J. Marc C.; Elting, Jan-Willem J.; Fidler, Vaclav; Staal, Michiel J.

It has been shown that transcutaneous electrical neurostimulation (TENS) reduces sympathetic tone. Spinal cord stimulation (SCS) has proven qualities to improve coronary, peripheral, and cerebral blood circulation. Therefore, we postulate that TENS and SCS affect the autonomic nervous system in

Neurostimulation for neck pain and headache.

Science.gov (United States)

Hong, Jennifer; Ball, Perry A; Fanciullo, Gilbert J

2014-03-01

Patients with medically refractory headache disorders are a rare and challenging-to-treat group. The introduction of peripheral neurostimulation (PNS) has offered a new avenue of treatment for patients who are appropriate surgical candidates. The utility of PNS for headache management is actively debated. Preliminary reports suggested that 60-80% of patients with chronic headache who have failed maximum medical therapy respond to PNS. However, complications rates for PNS are high. Recent publication of 2 large randomized clinical trials with conflicting results has underscored the need for further research and careful patient counseling. In this review, we summarize the current evidence for PNS in treatment of chronic migraine, trigeminal autonomic cephalagias and occipital neuralgia, and other secondary headache disorders. © 2014 American Headache Society.

Personality : Predictor of neurostimulation outcomes in patients with chest pain and normal coronary arteries

NARCIS (Netherlands)

de Vries, J; DeJongste, MJL; Versteegen, GJ; Durenkamp, A; Staal, MJ

Objectives. To study the impact of personality traits on the effect of neurostimulation in patients with chest pain and normal coronary arteries. Materials and Methods. Using the Dutch personality questionnaire, we retrospectively studied the personality traits in 33 patients treated with

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs

Science.gov (United States)

Handford, Matthew L.; Srinivasan, Manoj

2016-02-01

Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user’s walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simultaneously optimizing human movements and prosthesis actuation, minimizing a weighted sum of human metabolic and prosthesis costs. The resulting Pareto optimal solutions predict that increasing prosthesis energy cost, decreasing prosthesis mass, and allowing asymmetric gaits all decrease human metabolic rate for a given speed and alter human kinematics. The metabolic rates increase monotonically with speed. Remarkably, by performing an analogous optimization for a non-amputee human, we predict that an amputee walking with an appropriately optimized robotic prosthesis can have a lower metabolic cost - even lower than assuming that the non-amputee’s ankle torques are cost-free.

Long-term effects of electrical neurostimulation in patients with unstable angina : Refractory to conventional therapies

NARCIS (Netherlands)

de Vries, Jessica; DeJongste, Mike J. L.; Zijlstra, Felix; Staal, Michiel

2007-01-01

Background. Patients with unstable angina pectoris may become refractory to conventional therapies. Electrical neurostimulation with transcutaneous electrical stimulation and/or spinal cord stimulation has been shown to be effective for patients with refractory unstable angina pectoris in hospital

The Angelchik prosthesis

International Nuclear Information System (INIS)

Fargnoli, R.; Bozza, A.; Magnoli, A.; Villari, N.; Pernice, L.M.; Andreoli, F.; Lombardi, P.

1989-01-01

The Angelchik prosthesis is used in the surgical treatment of gastroesophageal reflux. Operated patients are preliminary examined with imaging techniques, but manometric and acidometric techniques are also used. Although the conventional esophagogram still maintains its diagnostic significance, Computed Tomography (CT) has become the first-choice imaging modality. CT allows the correct evaluation of both the state of the prosthesis and its relationship to the esophagus and gastric fundus. The possible postoperative complications following an incorrect placement of the prosthesis can be accurately diagnosed too. The authors report their experience in the study of 5 patients examined with both conventional radiology and CT

Neurostimulation of the cholinergic anti-inflammatory pathway ameliorates disease in rat collagen-induced arthritis.

Directory of Open Access Journals (Sweden)

Yaakov A Levine

Full Text Available The inflammatory reflex is a physiological mechanism through which the nervous system maintains immunologic homeostasis by modulating innate and adaptive immunity. We postulated that the reflex might be harnessed therapeutically to reduce pathological levels of inflammation in rheumatoid arthritis by activating its prototypical efferent arm, termed the cholinergic anti-inflammatory pathway. To explore this, we determined whether electrical neurostimulation of the cholinergic anti-inflammatory pathway reduced disease severity in the collagen-induced arthritis model.Rats implanted with vagus nerve cuff electrodes had collagen-induced arthritis induced and were followed for 15 days. Animals underwent active or sham electrical stimulation once daily from day 9 through the conclusion of the study. Joint swelling, histology, and levels of cytokines and bone metabolism mediators were assessed.Compared with sham treatment, active neurostimulation of the cholinergic anti-inflammatory pathway resulted in a 52% reduction in ankle diameter (p = 0.02, a 57% reduction in ankle diameter (area under curve; p = 0.02 and 46% reduction overall histological arthritis score (p = 0.01 with significant improvements in inflammation, pannus formation, cartilage destruction, and bone erosion (p = 0.02, accompanied by numerical reductions in systemic cytokine levels, not reaching statistical significance. Bone erosion improvement was associated with a decrease in serum levels of receptor activator of NF-κB ligand (RANKL from 132±13 to 6±2 pg/mL (mean±SEM, p = 0.01.The severity of collagen-induced arthritis is reduced by neurostimulation of the cholinergic anti-inflammatory pathway delivered using an implanted electrical vagus nerve stimulation cuff electrode, and supports the rationale for testing this approach in human inflammatory disorders.

Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia.

Science.gov (United States)

Alwaal, Amjad; Al-Sayyad, Ahmad J

2017-01-01

Erectile dysfunction is a prevalent disease affecting over 50% of men between the ages of 40 and 70 years. Penile prosthesis represents the end of the line treatment when other less invasive therapies fail or are contraindicated. Male stress urinary incontinence can significantly diminish quality of life and lead to embarrassment and social withdrawal. Surgical therapies, such as male urethral slings and artificial urinary sphincters (AUS), are considered effective and safe treatments for male stress incontinence. No data exist on the utilization of penile prosthesis or male incontinence surgical treatment in Saudi Arabia. Generally, urological prosthetic surgery is performed either in private hospitals or in government hospitals. Our aim was to assess the trend of penile prosthesis and male incontinence device utilization in Saudi Arabia. We utilized sales' data of penile prosthetics, male slings, and AUS from the only two companies selling these devices in Saudi Arabia (AMS ® and Coloplast ® ), from January 2013 to December 2016. There were 2599 penile prosthesis implantation procedures done in the study period, with 67% of them performed in private institutions. There was a progressively increased use of penile prosthetics which nearly doubled from 2013 to 2016. The main type of prosthesis utilized was the semirigid type 70% versus 11% of the 2-piece inflatable and 17% of the 3-piece inflatable device. Only 10 slings and 31 AUS were inserted during the same study period. There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

Auto-Targeted Neurostimulation Is Not Superior to Placebo in Chronic Low Back Pain: A Fourfold Blind Randomized Clinical Trial.

Science.gov (United States)

Aguilar Ferrándiz, Maria Encarnación; Nijs, Jo; Gidron, Yori; Roussel, Nathalie; Vanderstraeten, Rob; Van Dyck, Dries; Huysmans, Eva; De Kooning, Margot

2016-07-01

Myofascial trigger points (MTrPs) are common in people with musculoskeletal pain and may play a role in chronic nonspecific low back pain (CLBP). One of the potential treatments of MTrPs is the Nervomatrix Soleve® auto-targeted neurostimulation device, providing targeted transcutaneous electrical nerve stimulation (TENS) to MTrPs in the lower back muscles. To date, no controlled studies have evaluated the effectiveness of this device for the pain management of this population. To examine whether the Nervomatrix Soleve® auto-targeted neurostimulation device is superior over placebo for the treatment of CLBP. A fourfold-blind randomized controlled trial was conducted. Brussels University Hospital, health care centers and pharmacies around Belgium. Participants with CLBP for at least 3 months were randomly assigned to the experimental (the Nervomatrix Soleve® auto-targeted neurostimulation device providing TENS-stimulation and mechanical pressure) or placebo group (the Nervomatrix Soleve® auto-targeted neurostimulation device providing mechanical pressure alone without current). The treatment protocol in both groups consisted of 6 treatment sessions per patient. Participants were evaluated at baseline prior to the intervention, immediately following treatment, and at one month follow-up. Pain and pain behavior (steps climbed) were assessed as primary outcome measures. Secondary outcome measures were pain functioning, health beliefs, symptoms of central sensitization, pain catastrophizing, and kinesiophobia. In total, 39 participants were included in the study. Participants in both groups improved significantly for pain and functioning, but no significant differences were observed between groups. These improvements were not clinically meaningful for any of the reported measures. The health beliefs changed significantly in both groups (P pain, pain behavior, functioning, central sensitization, pain catastrophizing, and health beliefs.

Perivalvular pannus and valve thrombosis: two concurrent mechanisms of mechanical valve prosthesis dysfunction.

Science.gov (United States)

Arnáiz-García, María Elena; González-Santos, Jose María; Bueno-Codoñer, María E; López-Rodríguez, Javier; Dalmau-Sorlí, María José; Arévalo-Abascal, Adolfo; Arribas-Jiménez, Antonio; Diego-Nieto, Alejandro; Rodríguez-Collado, Javier; Rodríguez-López, Jose María

2015-02-01

A 78-year-old woman was admitted to our institution with progressive dyspnea. She had previously been diagnosed with rheumatic heart disease and had undergone cardiac surgery for mechanical mitral valve replacement ten years previously. Transesophageal echocardiography revealed blockage of the mechanical prosthesis and the patient was scheduled for surgery, in which a thrombus was removed from the left atrial appendage. A partial thrombosis of the mechanical prosthesis and circumferential pannus overgrowth were concomitantly detected. Prosthetic heart valve blockage is a rare but life-threatening complication, the main causes of which are thrombosis and pannus formation. The two conditions are different but both are usually misdiagnosed. Two concurrent mechanisms of prosthesis blockage were found in this patient. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

[Efficacy and safety of ultrasound-guided or neurostimulator-guided bilateral axillary brachial plexus block].

Science.gov (United States)

Xu, C S; Zhao, X L; Zhou, H B; Qu, Z J; Yang, Q G; Wang, H J; Wang, G

2017-10-17

Objective: To explore the efficacy and safety of bilateral axillary brachial plexus block under the guidance of ultrasound or neurostimulator. Methods: From February 2012 to April 2014, 120 patients undergoing bilateral hand/forearm surgery in Beijing Jishuitan Hospital were enrolled and anaesthetized with bilateral axillary brachial plexus block. All patients were divided into two groups randomly using random number table: the ultrasound-guided group (group U, n =60) and the neurostimulator-guidedgroup (group N, n =60). The block was performed with 0.5% ropivacaine. Patients' age, sex and operation duration were recorded. Moreover, success rate, performance time, onset of sensor and motor block, performance pain, patient satisfaction degree and the incidence of related complications were also documented. Venous samples were collected at selected time points and the total and the plasma concentrations of ropivacaine were analyzed with HPLC. Results: The performance time, the onset of sensor block and the onset of motor block of group U were (8.2±1.5), (14.2± 2.2)and (24.0±3.5)min respectively, which were markedly shorter than those in group N( (14.6±3.9), (19.9±3.8), (28.8±4.2)min, respectively), and the differences were statistically significant( t =11.74, 10.09, 6.73, respectively, all P 0.05). No analgesic was superadded and no other anesthesia methods were applied. No complications were detected perioperatively. Conclusions: The bilateral axillary brachial plexus block under the guidance of ultrasound or neurostimulator are both effective and safe for bilateral hand/forearm surgery. However, the ultrasound-guided block may be more clinically beneficial because of its shorter performance time, rapid onset and higher patient satisfaction degree.

Angina pectoris refractory for conventional therapy--is neurostimulation a possible alternative treatment?

Science.gov (United States)

Hautvast, R W; DeJongste, M J; ter Horst, G J; Blanksma, P K; Lie, K I

1996-07-01

The treatment of angina pectoris as a symptom of coronary artery disease usually is focused on restoring the balance between oxygen demand and supply of the myocardium by administration of drugs interfering in heart rate, cardiac pre- and afterload, and coronary vascular tone. For nonresponders to drug therapy or for those with jeopardized myocardium, revascularization procedures such as coronary bypass surgery and percutaneous transluminal coronary angioplasty are at hand. However, the atherosclerotic process is not stopped by these therapies and, at longer terms, angina may recur. It is not always possible to revascularize all the patients who do not positively react to medical treatment. Those with angina, not responding to adequate medication and who are not suitable anymore for revascularization, are considered to suffer from refractory angina pectoris. This group of patients has a poor quality of life, for their exercise tolerance is severely afflicted. For these patients, neurostimulation has been described repeatedly as an effective and safe therapy. The mechanism of action of neurostimulation is not completely known, but recent studies suggest an anti-ischemic effect, exerted through changes in myocardial blood flow. As soon as its safety is sufficiently established, it may become a useful alternative in the treatment of refractory angina pectoris.

[Longterm results of cervical arthroplasty with disc prosthesis. A literature review].

Science.gov (United States)

Fransen, P; Schils, F

2014-01-01

Cervical arthroplasty has now been performed for over 10 years. Despite the large number of implanted artificial discs, the quality of the published studies is weak, and very few report a follow up exceeding two years. We reviewed the literature on cervical total disc replacement, focusing on publications reporting a follow-up of more than two years. The selection of patients, the type of implant and the surgical technique seem to influence greatly the quality of the clinical and radiological results. The occurrence of heterotopic ossifications around the implant seems to be the rule rather than the exception. Wear debris are likely to be observed in the vicinity of the prosthesis. Most long term studies also report a progressive decrease in the range of motion of the prosthesis, although without influence on the clinical evolution. It seems reasonable to say that cervical disc prosthesis is not inferior to discectomy and fusion, and that these implants allow a short term preservation of cervical mobility, but the efficacy in preventing adjacent segment disease or a favourable costleffectiveness ratio have yet to be demonstrated. A more widespread use of cervical disc prosthesis can only be suggested when these questions have been answered by long term follow-up studies.

Nasal prosthesis rehabilitation: a case report

DEFF Research Database (Denmark)

Jain, Sumeet; Maru, Kavita; Shukla, Jyotsana

2011-01-01

Facial defects resulting from neoplasm, congenital malformation or trauma can be restored with facial prosthesis using different materials and retention methods to achieve life-like look and function. A nasal prosthesis can re-establish esthetic form and anatomic contours for mid-facial defects...... the non-surgical rehabilitation, with polymethyl meth-acrylate resin, nasal prosthesis for a patient who received partial rhinectomy as a result of squamous cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of the patient with a mechanical retained design using...

Modulation of cerebral blood flow with transcutaneous electrical neurostimulation (TENS) in patients with cerebral vasospasm after subarachnoid hemorrhage

NARCIS (Netherlands)

ter Laan, Mark; van Dijk, J.M.C.; Stewart, Roy; Staal, Michiel J; Elting, Jan-Willem J.

ObjectivesTranscutaneous electrical neurostimulation (TENS) and spinal cord stimulation have been shown to increase peripheral and cerebral blood flow. We postulate that certain pathological conditions attenuate cerebral autoregulation, which may result in a relative increase of the importance of

Modulation of cerebral blood flow with transcutaneous electrical neurostimulation (TENS) in patients with cerebral vasospasm after subarachnoid hemorrhage

NARCIS (Netherlands)

Laan, M. ter; Dijk, J.M. van; Stewart, R.; Staal, M.J.; Elting, J.W.

2014-01-01

OBJECTIVES: Transcutaneous electrical neurostimulation (TENS) and spinal cord stimulation have been shown to increase peripheral and cerebral blood flow. We postulate that certain pathological conditions attenuate cerebral autoregulation, which may result in a relative increase of the importance of

Comparison of Range of Motion After Total Knee Prosthesis According to Different Type of Prosthesis

Directory of Open Access Journals (Sweden)

Firat Seyfettinoglu

2016-07-01

Full Text Available Aim: The aim of this study is to determine the effectiveness and range of motion of different type of knee prosthesis. Material and Method: This study includes 180 of 225 patients (139 F, 41 M, average age: 65, range of age: 51-82 between April 2005 and September 2007 with the diagnosis of gonarthrosis. All patients underwent to primary total knee arthroplasty. Primary osteoartrhritis is the reason of gonarthrosis. The patients with secondary osteoartrhritis were excluded from the study. All the patients were operated by the same surgical team and rehabilitated after surgery. Patella didnt change any patient. PCL was protected in some of the patients and cut some of patients. Totally seven type prosthesis in 16 subgroup were applied to the patients. All measurement were done by the same surgeon. Average follow up period was 31 months (24-49 months. Results: Patients without subgrouping were tested according to the range of motion before and after surgery to the type of the prosthesis trademark. Range of motion was decreased with the usage of Rotaglide and LCS® type of prosthesis. Range of motion didnt change with the usage of Maxim and Kinemax type. The range of motion increased in the other trademark of prosthesis. Flexion angle was increased statistically significant with nexgen® and scorpio® prosthesis (p

Implant-Retained Auricular Prosthesis: A Case Report

OpenAIRE

Ozturk, A. Nilgun; Usumez, Aslihan; Tosun, Zekeriya

2010-01-01

Extraoral implant retained prosthesis have been proven to be a predictable treatment option for maxillofacial rehabilitation. This case report describes the clinical and laboratory procedures for fabricating an auricular prosthesis. In this case report, an auricular prosthesis was fabricated for a patient who lost the left and right external ear in an electrical burn. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This...

Permanent Quadriplegia Following Replacement of Voice Prosthesis.

Science.gov (United States)

Ozturk, Kayhan; Erdur, Omer; Kibar, Ertugrul

2016-11-01

The authors presented a patient with quadriplegia caused by cervical spine abscess following voice prosthesis replacement. The authors present the first reported permanent quadriplegia patient caused by voice prosthesis replacement. The authors wanted to emphasize that life-threatening complications may be faced during the replacement of voice prosthesis. Care should be taken during the replacement of voice prosthesis and if some problems have been faced during the procedure patients must be followed closely.

Patients with hip prosthesis: radiotherapy treatment planning considerations

International Nuclear Information System (INIS)

Ganesh, K.M.; Supe, Sanjay S.

2000-01-01

The number of patients with hip prosthesis undergoing radiotherapy for pelvic cancer worldwide is increasing. This might be of importance depending on the materials in the prosthesis and whether any of the treatment fields are involved in the prosthesis. Radiotherapy planning involving the pelvic region of patients having total hip prosthesis has been found to be difficult due to the effect of the prosthesis on the dose distribution. This review is intended to project dosimetric considerations and possible solutions to this uncommon problem

21 CFR 872.3960 - Mandibular condyle prosthesis.

Science.gov (United States)

2010-04-01

... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... requirement for premarket approval for any mandibular condyle prosthesis intended to be implanted in the human...

Effect of Patient-Prosthesis Mismatch in Aortic Position on Late-Onset Tricuspid Regurgitation and Clinical Outcomes after Double Valve Replacement.

Science.gov (United States)

Lee, Seung Hyun; Youn, Young Nam; Chang, Byung Chul; Joo, Hyun Chel; Lee, Sak; Yoo, Kyung Jong

2017-09-01

Significant late-onset tricuspid regurgitation (TR) is unfortunately common after double valve replacement (DVR); however, its underlying factors remain undefined. We evaluated the effect of aortic patient-prosthesis mismatch (PPM) on late-onset TR and clinical outcomes after DVR. Of the 2392 consecutive patients who underwent aortic valve replacement between January 1990 and May 2014 at our institution, we retrospectively studied 462 patients who underwent DVR (excluding concomitant tricuspid valvular annuloplasty or replacement). Survival and freedom from grade >3 TR were compared between PPM (n=152) and non-PPM (n=310) groups using the Kaplan-Meier method. Although the overall survival rates were similar between the two groups at 5 and 10 years (95%, 91% vs. 96%, 93%, p=0.412), grade >3 TR-free survival was significantly lower in the PPM group (98%, 91% vs. 99%, 95%, p=0.014). Small body-surface area, atrial fibrillation, PPM, and subaortic pannus were risk factors for TR progression. However, aortic prosthesis size and trans-valvular pressure gradient were not significant factors for either TR progression or overall survival. Aortic PPM in DVR, regardless of mitral prosthesis size, was associated with late TR progression, but was not significantly correlated with overall survival. Therefore, we recommend careful echocardiographic follow-up for the early detection of TR progression in patients with aortic PPM in DVR. © Copyright: Yonsei University College of Medicine 2017

Dosimetry of a silicone breast prosthesis

International Nuclear Information System (INIS)

McGinley, P.H.; Powell, W.R.; Bostwick, J.

1980-01-01

Dose measurements were conducted in a phantom which simulates breast tissue and in another phantom which simulates a breast containing a silicone prosthesis. No detectable difference was found when the irradiations were carried out with tangential beams of 60 Co radiation. The degree of backscatter and absorption of radiation by the prosthesis and phantom were also similar. A slight decrease in dose of approximately 8% was found at the interface between the prosthesis and muscle-equivalent material

[Current status of neurostimulation and neuromodulation for vesicourethral dysfunction].

Science.gov (United States)

González-Chamorro, F; Verdú Tartajo, F; Hernández Fernández, C

1997-01-01

To describe the current indications, techniques and results of sacral root stimulation in patients with spinal cord lesions as a treatment for patients with high pressure bladders and/or urinary incontinence despite conservative management, as well as sacral root neuromodulation with permanent stimulators for complex bladder dysfunction: vesical instability, sensory urgency, chronic pelvic pain and chronic voiding dysfunction. The literature is reviewed, both techniques are described and the results of the most significant series are discussed, with special reference to the first groups that utilized these techniques. There is ample experience in the application of sacral root electrical stimulation. The reported results are comparable with those achieved by other treatments, such as augmentation cystoplasty. Neurostimulation and neuromodulation techniques are simple, the complications are minimal and they do not prelude the use of other therapies.

Duocentric® reversed shoulder prosthesis and Personal Fit® templates: innovative strategies to optimize prosthesis positioning and prevent scapular notching.

Science.gov (United States)

Trouilloud, P; Gonzalvez, M; Martz, P; Charles, H; Handelberg, F; Nyffeler, R W; Baulot, E

2014-05-01

We describe our experience with a new system of patient-specific template called Personal Fit(®), which is unique in shoulder surgery and used in combination with Duocentric(®) prosthesis. The reverse prosthesis's concept is the invention of Paul Grammont, developed with Grammont's team of Dijon University as from 1981, which led to the first reversed total shoulder prosthesis called Trumpet in 1985. The Duocentric(®) prosthesis developed in 2001 is the third-generation prosthesis, coming from the Trumpet and the second-generation prosthesis Delta(®) (DePuy). This prosthesis provides a novel solution to the notching problem with an inferior overhang integrated onto the glenoid baseplate. Personal Fit(®) system is based on reconstructing the shoulder joint bones in three dimensions using CT scan data, placing a landmark on the scapula and locating points on the glenoid and humerus. That will be used as a reference for the patient-specific templates. We study the glenoid position planned with Personal Fit(®) software relative to native glenoid position in 30 cases. On average, the difference between the planned retroversion (or anteversion in one case) and native retroversion was 8.6°.

Malrotation of the McGhan Style 510 prosthesis.

NARCIS (Netherlands)

Schots, J.M.; Fechner, M.R.; Hoogbergen, M.M.; Tits, H.W.H.J.

2010-01-01

BACKGROUND: Anatomically shaped cohesive silicone breast implants are frequently used in aesthetic and reconstructive surgery. After successful results with the Style 410 prosthesis, McGhan (Natrelle, Allergan) introduced the Style 510 prosthesis. After using this novel prosthesis, the authors

Finger prosthesis: a boon to handicapped.

Science.gov (United States)

Gupta, Ridhima; Kumar, Lakshya; Rao, Jitendra; Singh, Kamleshwar

2013-08-29

This is a clinical case report of a 52-year-old male patient with four partially missing fingers of the left hand. The article describes the clinical and laboratory procedure of making prosthesis with modern silicone material. A wax pattern was fabricated using the right hand of the patient. A special type of wax was formulated to make the pattern so that it can be easily moulded and carved. Intrinsic and extrinsic staining was also performed to match the adjacent skin colour. The patient was given the finger prosthesis and was asked to use a half glove (sports) to mask the junction between the prosthesis and the normal tissue. It also provides additional retention to the artificial fingers. The patient felt his social acceptance improved after wearing the finger prosthesis.

Shielding of the Hip Prosthesis During Radiation Therapy for Heterotopic Ossification is Associated with Increased Failure of Prophylaxis

International Nuclear Information System (INIS)

Balboni, Tracy A.; Gaccione, Peter; Gobezie, Reuben; Mamon, Harvey J.

2007-01-01

Purpose: Radiation therapy (RT) is frequently administered to prevent heterotopic ossification (HO) after total hip arthroplasty (THA). The purpose of this study was to determine if there is an increased risk of HO after RT prophylaxis with shielding of the THA components. Methods and Materials: This is a retrospective analysis of THA patients undergoing RT prophylaxis of HO at Brigham and Women's Hospital between June 1994 and February 2004. Univariate and multivariate logistic regressions were used to assess the relationships of all variables to failure of RT prophylaxis. Results: A total of 137 patients were identified and 84 were eligible for analysis (61%). The median RT dose was 750 cGy in one fraction, and the median follow-up was 24 months. Eight of 40 unshielded patients (20%) developed any progression of HO compared with 21 of 44 shielded patients (48%) (p = 0.009). Brooker Grade III-IV HO developed in 5% of unshielded and 18% of shielded patients (p 0.08). Multivariate analysis revealed shielding (p = 0.02) and THA for prosthesis infection (p = 0.03) to be significant predictors of RT failure, with a trend toward an increasing risk of HO progression with age (p = 0.07). There was no significant difference in the prosthesis failure rates between shielded and unshielded patients. Conclusions: A significantly increased risk of failure of RT prophylaxis for HO was noted in those receiving shielding of the hip prosthesis. Shielding did not appear to reduce the risk of prosthesis failure

21 CFR 878.3800 - External aesthetic restoration prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External aesthetic restoration prosthesis. 878... External aesthetic restoration prosthesis. (a) Identification. An external aesthetic restoration prosthesis... (general controls). The device is exempt from the premarket notification procedures in subpart E of part...

Rehabilitation of a Patient with an Intra Oral Prosthesis and an Extra Oral Orbital Prosthesis Retained with Magnets

OpenAIRE

Pattanaik, Seema; Wadkar, Aarti P.

2011-01-01

This clinical case report deals with a rehabilitation of a patient with an extensive maxillary and orbital defect using an intra oral prosthesis obturating the maxillary defect and extra oral orbital prosthesis retained with rare-earth magnets for secondary retention; primary retention was derived by snug fit of the prosthesis to underlying and adjacent tissues. The rehabilitation resulted in improved function, esthetics and comfort to the patient thus enabling him to lead a normal life.

Smooth muscle fatigue due to repeated urinary bladder neurostimulation: an in vivo study.

Science.gov (United States)

Bross, S; Schumacher, S; Scheepe, J R; Seif, C; Jünemann, K P; Alken, P

1999-01-01

The presented study investigates the influence of different pause lengths between two consecutive stimulations of the S3 roots on intravesical pressure during bladder neurostimulation. In eight male foxhounds (aged 7-18 months), laminectomy and placement of a modified Brindley electrode were performed. In four series with different pause lengths between two consecutive stimulations (1, 3, 5, and 15 min), the maximum intravesical pressure was measured during stimulation. The changes in intravesical pressure were registered in these four series, each series with six stimulations. A 15-min interval elapsed before the commencement of each series. In the series with a pause length of 15 min, the consecutive stimulations did not result in significant changes in maximum intravesical pressure. In the 5-min series, a significant decrease in intravesical pressure was not observed after the third stimulation. In the 3-min series, a significant decrease was seen at almost every stimulation (average decrease of 3.8% per stimulation) and in the 1-min series, a significant decrease was also observed at almost every stimulation (average decrease of 5.9% per stimulation). The results of repeated bladder neurostimulation demonstrate that the maximum intravesical pressure is dependent on the pause length between two consecutive stimulations. The detrusor muscle showed reversible and short-lived signs of fatigue. This implies the importance of a minimum 5-min interval between two subsequent stimulations. A pause length <5 min leads to a falsification of the results and thus to lower validity of the investigation.

Mood disorders in elderly population: neurostimulative treatment possibilities.

Science.gov (United States)

Rosenberg, Oded; Shoenfeld, Netta; Kotler, Moshe; Dannon, Pinhas N

2009-06-01

Treatment of mood disorders is one of the most challenging territories in elderly. Effectiveness of different treatment strategies could be related to age, sex and physical conditions. The side effect profile in this population also affects pharmacological interventions. Our review includes the neurostimulative treatment strategies in elderly. However, possible treatment strategies such as electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS) and deep brain stimulation (DBS) were less studied in elderly. ECT was found to be an effective treatment procedure in mood disorders. Few double-blind sham controlled studies were conducted and demonstrated effectiveness of TMS. DBS has lack of double-blind studies. ECT seems to be the golden standard for the treatment resistant elderly patients, yet side effect profile of ECT in elderly will be discussed. Double -blind sham controlled studies with larger samples are necessary to confirm preliminary results with transcranial direct current stimulation (tDCS), magnetic seizure therapy (MST) and VNS, DBS.

Power Link Optimization for a Neurostimulator in Nasal Cavity

Directory of Open Access Journals (Sweden)

Seunghyun Lee

2017-01-01

Full Text Available This paper examines system optimization for wirelessly powering a small implant embedded in tissue. For a given small receiver in a multilayer tissue model, the transmitter is abstracted as a sheet of tangential current density for which the optimal distribution is analytically found. This proposes a new design methodology for wireless power transfer systems. That is, from the optimal current distribution, the maximum achievable efficiency is derived first. Next, various design parameters are determined to achieve the target efficiency. Based on this design methodology, a centimeter-sized neurostimulator inside the nasal cavity is demonstrated. For this centimeter-sized implant, the optimal distribution resembles that of a coil source and the optimal frequency is around 15 MHz. While the existing solution showed an efficiency of about 0.3 percent, the proposed system could enhance the efficiency fivefold.

Attachment-retained gingival prosthesis for implant-supported fixed dental prosthesis in the maxilla: a clinical report.

Science.gov (United States)

Aparecida de Mattias Sartori, Ivete; Uhlendorf, Yuri; Padovan, Luiz Eduardo Marques; Junior, Paulo Domingos Ribeiro; Melo, Ana Cláudia Moreira; Tiossi, Rodrigo

2014-12-01

The rehabilitation of edentulous maxillae is a complex procedure due to the involvement of esthetic and functional requirements. A trial maxillary denture can be used to identify the need for adequate upper lip support when replacing removable complete dentures by implant-fixed dental prostheses. This clinical report describes the outcome of the rehabilitation of an edentulous atrophic maxilla with unfavorable maxillomandibular relationship and deficient upper lip support. A trial denture was fabricated and used to diagnose the need for a prosthesis capable of restoring the upper lip support. The reduced upper lip support was also confirmed by a lateral cephalogram. The patient was rehabilitated by an implant-fixed dental prosthesis associated with an attachment-retained gingival prosthesis. The case presented shows that when loss of upper lip support is detected and the patient does not wish to undergo further surgical reconstruction procedure, the retention of a gingival prosthesis using a ball attachment is a satisfactory treatment option. © 2014 by the American College of Prosthodontists.

Prosthesis infections after orthopedic joint replacement

DEFF Research Database (Denmark)

Song, Zhijun; Borgwardt, Lotte; Høiby, Niels

2013-01-01

Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore...

21 CFR 872.3950 - Glenoid fossa prosthesis.

Science.gov (United States)

2010-04-01

...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the temporomandibular...

Failed total carpometacarpal joint prosthesis of the thumb

DEFF Research Database (Denmark)

Hansen, Torben Bæk; Homilius, Morten

2010-01-01

Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis. T...... in eight of 10 patients, but the mean Disabilities of the arm, shoulder, and hand (DASH) scores, self-reported pinch-grip-related function, and pain were comparable with our earlier published results with the Elektra carpometacarpal total joint prosthesis.......Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis....... The male:female ratio was 1:4 and the mean duration of observation 32 months (range 6-52). In three patients the revised implant was a MOJE uncemented carpometacarpal joint prosthesis and in seven patients an Elektra uncemented one. At follow-up grip strength was reduced to less than 90% of the other hand...

Stretch due to Penile Prosthesis Reservoir Migration

Directory of Open Access Journals (Sweden)

E. Baten

2016-03-01

Full Text Available A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch.

Rehabilitation of amputed thumb with a silicone prosthesis

OpenAIRE

Asnani, Pooja; Shivalingappa, Chandu Giriyapura; Mishra, Sunil Kumar; Somkuwar, Kirti; Khan, Faisal

2015-01-01

Creating prosthesis, having realistic skin surface and seamless visual integration with the surrounding tissues, requires both artistic and technical skill. Anatomical design, thin margins, lifelike fingernails and realistic color/contours are essential for patient satisfaction. Prosthesis is especially useful in case of lost body parts, as reconstructive surgery cannot fully restore aesthetics. This case report describes a simple technique for fabricating silicon finger prosthesis for a pati...

Development and clinical application of a new testicular prosthesis.

Science.gov (United States)

Ning, Ye; Cai, Zhikang; Chen, Huixing; Ping, Ping; Li, Peng; Wang, Zhong; Li, Zheng

2011-11-01

A new type of testicular prosthesis made of silastic with an elliptical shape to mimic a normal testis was developed by our team and submitted for patenting in China. The prosthesis was produced in different sizes to imitate the normal testis of the patient. To investigate the effects and safety of the testicular prosthesis, 20 patients receiving testicular prosthesis implantation were recruited for this study. Follow-up after 6 months revealed no complications in the patients. All the patients answered that they were satisfied with their body image and the position of the implants, 19 patients were satisfied with the size and 16 patients were satisfied with the weight. These results show that the testicular prosthesis used in this study can meet patient's expectations. Patients undergoing orchiectomy should be offered the option to receive a testicular prosthesis implantation. The dimensions and weight of the available prosthetic implants should be further addressed to improve patient satisfaction.

Different techniques in fabrication of ocular prosthesis.

Science.gov (United States)

Cevik, Pinar; Dilber, Erhan; Eraslan, Oguz

2012-11-01

Loss of an eye caused by cancer, trauma, or congenital defect creates a deep psychological impact on an individual's life especially social and professional life. Custom-made prosthesis, compared to stock prosthesis, provides a better fit to the eye socket, better cosmetic results, and less discomfort to the patient in the long term. The main objective of this article was to describe 3 different alternative and practical techniques of fabricating custom-made ocular prosthesis. An impression of anophthalmic socket was made with the addition of cured silicone-based precision impression material in all techniques. A master cast was prepared and duplicated with condensation silicone. A self-cure acrylic resin was polymerized in the silicone model and was fitted into the patient's eye socket. A digital photograph of the patient's iris was made using a digital camera and printed on good-quality photo paper in various shades and sizes in the first and the second techniques. Then the photo paper was coated with PVC so as not to allow any color flowing. The proper iris was then inserted to the acrylic base. The prosthesis was final processed using orthodontic heat polymerizing clear acrylic resin.In the other technique, after the trying-in process with wax pattern, an acrylic base was fabricated using heat polymerizing scleral acrylic resin. The prosthetic iris was fabricated from a transparent contact lens by painting the lens with watercolor paints and attaching it to an acrylic resin with tissue conditioner. The final process was made with heat polymerizing transparent acrylic resin. Custom-made prosthesis allows better esthetic and functional results to the patient in comparison to stock prosthesis. Further follow-up is necessary to check the condition and fit of the ocular prosthesis in such patients.

Femoral Prosthesis Infection by Rhodotorula mucilaginosa▿

Science.gov (United States)

Savini, Vincenzo; Sozio, Federica; Catavitello, Chiara; Talia, Marzia; Manna, Assunta; Febbo, Fabio; Balbinot, Andrea; Di Bonaventura, Giovanni; Piccolomini, Raffaele; Parruti, Giustino; D'Antonio, Domenico

2008-01-01

This case report is a case history of a femoral prosthesis infection caused by Rhodotorula mucilaginosa in a human immunodeficiency virus patient. Though the pathogenicity of this organism for bone tissue has been previously reported, this is the first reported case of an orthopedic prosthesis infection by this species of the genus Rhodotorula. PMID:18753353

Kinematic analysis of a posterior-stabilized knee prosthesis.

Science.gov (United States)

Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

2015-01-20

The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

Directory of Open Access Journals (Sweden)

Zhi-Xin Zhao

2015-01-01

Full Text Available Background: The goal of total knee arthroplasty (TKA is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Results: Both the output data trends and the measured values derived from the normal knee′s kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

Science.gov (United States)

Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

2015-01-01

Background: The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0–135° flexion. Results: Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, “rollback” compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis. PMID:25591565

Prosthetic management of mid-facial defect with magnet-retained silicone prosthesis.

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Buzayan, Muaiyed M

2014-02-01

Mid-facial defect is one of the most disfiguring and impairing defects. A design of prosthesis that is aesthetic and stable can be precious to a patient who has lost part of his face due to surgical excision. Prosthesis can restore the patients' self-esteem and confidence, which affects the patients and their life style. The aim of this case report is to describe a technique of mid-facial silicone prosthesis fabrication. To provide an aesthetic and stable facial prosthesis, the extra-oral prosthesis was fabricated using silicone material, while the intra-oral defect was restored with obturator prosthesis, and then both prostheses were connected and attached to each other using magnets. This clinical report describes the rehabilitation of a large mid-facial defect with a two-piece prosthesis. The silicone facial prosthesis was made hollow and lighter by using an acrylic framework. Two acrylic channels were included within the facial prosthesis to provide the patient with clean and patent airways. A sectional mid-facial prosthesis was made and retained in place by using magnets, which resulted in a significant improvement in the aesthetical and functional outcome without the need for plastic surgery. Silicone prostheses are reliable alternatives to surgery and should be considered in selected cases.

Body image and prosthesis satisfaction in the lower limb amputee.

OpenAIRE

Murray, Craig; Fox, Jezz

2002-01-01

Purpose: This study examines the relationship between prosthesis satisfaction and body image in lower limb prosthesis users, and the gendered variations within these relationships. Method: A total of 44 valid responses were obtained to an Internet survey regarding prosthesis satisfaction, body image, and phantom pain. Spearman Rho correlations were calculated for these three domains. Results: Moderate to high negative correlations were observed between Body Image Disturbance and Prosthesis Sa...

Self-contained inflatable penile prosthesis: magnetic resonance appearance

International Nuclear Information System (INIS)

Levin, M.F.; Munk, P.L.; Vellet, A.D.; Chin, J.L.

1994-01-01

The appearance of an inflatable penile prosthesis, visualized on a short tau inversion recovery sequence, is reported, in a patient who had magnetic resonance imaging for pelvic pain subsequent to radical cystoprostatectomy for bladder carcinoma. With suppression of adjacent fat signal, the prosthesis is well delineated from adjacent structures. The fluid-containing cylinders of the prosthesis are of very bright signal intensity, with the relief valve assembly of low signal intensity. 5 refs., 2 figs

Fabrication of temporary speech bulb prosthesis: A clinical report

OpenAIRE

Kasim Mohamed, K.; Anand Kumar, V.; Devi, N.; Padmanaban, T. V.

2010-01-01

Maxillofacial prosthesis is an art and science which not only replaces the lost structure sometimes it restores the functions also. Pharyngeal obturator is a prosthesis which closes the palatal and pharyngeal defects and improving the speech and other function. The following case report discusses palatopharyngeal insufficiency, impression procedures, fabrication of prosthesis and improvements in speech.

Femoral hip prosthesis design for Thais using multi-objective shape optimization

International Nuclear Information System (INIS)

Virulsri, Chanyaphan; Tangpornprasert, Pairat; Romtrairat, Parineak

2015-01-01

Highlights: • A multi-objective shape optimization was proposed to design hip prosthesis for Thais. • The prosthesis design was optimized in terms of safety of both cement and prosthesis. • The objective functions used the Soderberg fatigue strength formulations. • Safety factors of the cement and prosthesis are 1.200 and 1.109 respectively. • The newly designed prosthesis also fits well with chosen small-sized Thai femurs. - Abstract: The long-term success of Total Hip Arthroplasty (THA) depends largely on how well the prosthetic components fit the bones. The majority of cemented femoral hip prosthesis failures are due to aseptic loosening, which is possibly caused by cracking of the cement mantle. The strength of cement components is a function of cement mantles having adequate thickness. Since the size and shape of cemented femoral hip prostheses used in Thailand are based on designs for a Caucasian population, they do not properly conform to most Thai patients’ physical requirements. For these reasons, prostheses designed specifically for Thai patients must consider the longevity and functionality of both cement and prosthesis. The objective of this study was to discover a new design for femoral hip prostheses which is not only optimal and safe in terms of both cement and prosthesis, but also fits the selected Thai femur. This study used a small-sized Thai femoral model as a reference model for a new design. Biocompatible stainless steel 316L (SS316L) and polymethylmethacrylate (PMMA) were selected as raw materials for the prosthesis and bone cement respectively. A multi-objective shape optimization program, which is an interface between optimization C program named NSGA-II and a finite element program named ANSYS, was used to optimize longevity of femoral hip prostheses by varying shape parameters at assigned cross-sections of the selected geometry. Maximum walking loads of sixty-kilograms were applied to a finite element model for stress and

Closed-eye orbital prosthesis: a clinical report.

Science.gov (United States)

Hatamleh, Muhanad M; Watson, Jason; Srinivasan, Dilip

2015-03-01

One of the most challenging prostheses to fabricate is an acceptable orbital prosthesis. Successful reconstruction of the complex missing tissues, the globe, muscle, skin, and bony elements requires time and high levels of practical skill. A good match to the contralateral nondefect side will help mask the underlying defect and give the patient confidence to return to normal, routine life. The contralateral eye opening will commonly dictate the eye opening of such a prosthesis, but because of the expressive nature of the eye and its high levels of mobility, this can be difficult to achieve. This clinical report presents a patient who had an extended orbital exenteration and right maxillectomy to remove a maxillary squamous cell carcinoma. An alternative approach to constructing an orbital prosthesis was undertaken with the eye closed. Compared to the normal method of fabrication, this process was less complex and quicker, made the prosthesis less "staring," camouflaged the defect, and reduced the detection of the prosthesis because of movements in the remaining eye. The patient engaged in his routine daily life, which reinforced his self-esteem, confidence, and reintegration into the community. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Split-Framework in Mandibular Implant-Supported Prosthesis

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Danny Omar Mendoza Marin

2015-01-01

Full Text Available During oral rehabilitation of an edentulous patient with an implant-supported prosthesis, mandibular flexure must be considered an important biomechanical factor when planning the metal framework design, especially if implants are installed posterior to the interforaminal region. When an edentulous mandible is restored with a fixed implant-supported prosthesis connected by a fixed full-arch framework, mandibular flexure may cause needless stress in the overall restorative system and lead to screw loosening, poor fit of prosthesis, loss of the posterior implant, and patient’s discomfort due to deformation properties of the mandible during functional movements. The use of a split-framework could decrease the stress with a precise and passive fit on the implants and restore a more natural functional condition of the mandible, helping in the longevity of the prosthesis. Therefore, the present clinical report describes the oral rehabilitation of an edentulous patient by a mandibular fixed implant-supported prosthesis with a split-framework to compensate for mandibular flexure. Clinical Significance. The present clinical report shows that the use of a split-framework reduced the risk of loss of the posterior implants or screws loosening with acceptable patient comfort over the period of a year. The split-framework might have compensated for the mandibular flexure during functional activities.

Clinical Outcomes of Penile Prosthesis Implantation Surgery

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Onur Dede

2016-06-01

Full Text Available Objective: We aimed to evaluating the outcomes of in­flatable penile prosthesis implantations and partner sat­isfaction. Methods: Data of 52 patients who underwent penile prosthesis implantation in single center between May 2010 and December 2015 were retrospectively analyzed. Types of prosthesis, complication and satisfaction rates of patients were recorded by EDITS (Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire was used. Results: The mean age was 49.2±14.7 years for patients. The mean follow-up durations for 34.3±12.5 months. The mean hospital stay was 3.84±1.52 days. Evaluating of the couples satisfaction revealed that 44 (84% of the patient were very satisfied. There was not any complication and no patient need to underwent revision surgery. Conclusion: Inflatable penile prosthesis implants, with high levels of treatment success, patient and partner sat­isfaction, are effective and safe options for treatment of organic erectile dysfunction with acceptable complication and revision rates.

Hearing results using the SMart piston prosthesis.

Science.gov (United States)

Fayad, Jose N; Semaan, Maroun T; Meier, Josh C; House, John W

2009-12-01

SMart, a newly introduced piston prosthesis for stapedotomy, is a nitinol-based, heat-activated, self-crimping prosthesis. We review our hearing results and postoperative complications using this self-crimped piston prosthesis and compare them with those obtained using stainless steel or platinum piston prostheses. Audiometric results using the SMart piston are identical to those obtained using a conventional piston prosthesis. Retrospective chart review. Private neurotologic tertiary referral center. The 416 ears reviewed included 306 with a SMart prosthesis and 110 conventional prostheses. 61% were women. Mean follow-up time was 5.6 (standard deviation [SD], 6.3 mo) and 6.9 months (SD, 7.0 mo) for the 2 groups, respectively. Stapedotomy using the SMart or a conventional (non-SMart) prosthesis. Audiometric hearing results, including pure-tone average (PTA) and air-bone gap (ABG), and prevalence of postoperative complications. Mean postoperative PTA was 32.6 (SD, 16.8) dB for the SMart group and 29.4 (SD, 13.5) dB for the non-SMart group, with ABGs of 7.6 (SD, 8.9) and 6.0 (SD, 5.2) dB, respectively. Mean change (decrease) in ABG was 18.7 (SD, 13.1) dB for the SMart group and 19.9 (SD, 10.3) dB for the non-SMart group. High-frequency bone PTAs showed overclosure of 2.0 (SD, 7.9) dB for the SMart group and 3.6 (SD, 8.6) dB for the non-SMart group. Postoperative vertigo and tinnitus were infrequent. No significant differences in these audiometric outcomes or complication rates were noted between groups. There was no significant difference in rate of gap closure to within 10 dB (78.3 versus 84.2%, SMart and non-SMart, respectively) or 20 dB (94.2 and 98.0%). Compared with conventional stapes prostheses, the nitinol-based SMart is a safe and reliable stapes prosthesis that eliminates manual crimping without significantly altering the audiometric outcome. Complications are rare, but longer follow-up is needed before establishing long-term stability.

Neurostimulation and neuromodulation: a guide to selecting the right urologic patient.

Science.gov (United States)

Schmidt, R A; Doggweiler, R

1998-01-01

Sensory input has an important influence on the integrity of neural circuitry. Central nervous system circuitry is programmed and reinforced by everyday experience. Even the simplest of behaviors participate in this process. A balance between inhibition and facilitation must be maintained for the CNS to function normally. For example, the bladder stores urine because of the inhibition from a closed sphincter, and relaxation of the sphincter disinhibits the bladder to permit voiding. This synergistic 'seesaw' in reflex neural activity preserves the functional and anatomical integrity of the lower urinary tract. Dysfunction and anatomical change results when an unnatural bias develops between inhibitory and facilitatory neural activity. Neurostimulation has an inherent conditioning effect on neural excitability and can restore the neural equilibrium. Voiding diaries are very useful in documenting these changes.

Difficult factors in Management of Impacted Dental Prosthesis in Esophagus

Directory of Open Access Journals (Sweden)

Efiaty A. Soepardi

2005-03-01

Full Text Available A dental prosthesis which ingested and impacted in esophagus, is an emergency case and life threatening, so require immediate esophagoscopy intervention for removing. The objective of this study is to assess some factors can caused dtfficulties in diagnosing and treating the ingested and impacted dental prosthesis in the esophagus and their complications. This retrospective study analyzed patient’s chart whose underwent esophagoscopy for removing the impacted dental prosthesis in Dr. Cipto Mangunkusumo General Hospital, Jakarta, Indonesia during a period between January 1997 and December 2003. Neck-chest X-ray and esophagoscopy were performed in all patients to identify the existence of the dental prosthesis as a diagnostic and treatment procedure. The length of time for removing the dental prosthesis was recorded and stated as a less difficult esophagoscopy when it takes time less than 60 minutes and as a difficult  esophagoscopy takes 60 minutes or longer. Some risk difficulties factors were statistically analyzed. There were 53 patients of ingested dental prosthesis in esophagus. Only 51 cases were analyzed According to the length of time for removing the dental prosthesis by esophagoscopy, 22 patients were recorded as less difficult cases and 29 patients as difficult cases. Two cases among the cases needed cervicotomy after unsuccessful esophagoscopy removal. The difficulties to diagnose an impacted dental prosthesis in the esophagus caused by unreliable clinical history, unclear signs and symptoms, unable to be detected by X-ray and was not found during esophagoscopy. The difficulties in treating due to mucosal laceration, edema, bleeding, failure of the first extraction and conformity with the size and shape, the wire outside the dental prosthesis and the length of time stayed in the esophagus. (Med J Indones 2005; 14: 33-6Keywords: ingested dental prosthesis, radioluscent foreign body, length of time of esophagoscopy

Impact of aortic prosthesis-patient mismatch on left ventricular mass regression.

Science.gov (United States)

Alassal, Mohamed A; Ibrahim, Bedir M; Elsadeck, Nabil

2014-06-01

Prostheses used for aortic valve replacement may be small in relation to body size, causing prosthesis-patient mismatch and delaying left ventricular mass regression. This study examined the effect of prosthesis-patient mismatch on regression of left ventricular mass after aortic valve replacement. We prospectively studied 96 patients undergoing aortic valve replacement between 2007 and 2012. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography at 3 and 6 months postoperatively. Patient-prosthesis mismatch was defined as indexed effective orifice area ≤0.85 cm(2)·m(-2). Moderate prosthesis-patient mismatch was present in 25% of patients. There were no significant differences in demographic and operative data between patients with and without prosthesis-patient mismatch. Left ventricular dimensions, posterior wall thickness, transvalvular gradients, and left ventricular mass decreased significantly after aortic valve replacement in both groups. The interventricular septal diameter and left ventricular mass index regression, and left ventricular ejection fraction were better in patients without prosthesis-patient mismatch. There was a significant positive correlation between the postoperative indexed effective orifice area of each valve prosthesis and the rate of left ventricular mass regression. Prosthesis-patient mismatch leads to higher transprosthetic gradients and impaired left ventricular mass regression. A small-sized valve prosthesis does not necessarily result in prosthesis-patient mismatch, and may be perfectly adequate in patient with small body size. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

[The endo-exo prosthesis for patients with a problematic amputation stump].

Science.gov (United States)

Frölke, Jan Paul M; van de Meent, Henk

2010-01-01

Following lower limb amputation, quality of life is highly related to the ability to use a prosthetic limb. The conventional way to attach a prosthetic limb to the body is with a socket. Many patients experience serious discomfort wearing a conventional prosthesis because of pain, instability during walking, pressure sores, bad smell or skin irritation. In addition, sitting is uncomfortable and pelvic and lower back pain due to unstable gait is often seen in these patients. The main disadvantage of the current prosthesis is the attachment of a rigid prosthesis socket to a soft and variable body. The socket must fit tightly for stability during walking but should also be comfortable for sitting. The implantation of an osseointegrated, intramedullary, transcutaneously conducted prosthesis is a new procedure for attaching a limb prosthesis to the human body without the disadvantages of the conventional prosthesis. The intramedullary prosthesis is designed with a rough surface resembling cancellous bone to enable a secure solid integration with the long bone. We treated two patients with this new prosthesis, a 44-year-old man after a transfemoral amputation, and a 32-year-old woman after a lower leg amputation; both amputations were necessary because of trauma. Those two patients are now, more than one year after the operation, showing excellent functional results without infectious complications. We assume that endo-exo prosthesis may be a promising option for selected patients unable to use a conventional prosthesis because of a problematic amputation stump.

Clinical predictors of prosthesis-patient mismatch after aortic valve replacement for aortic stenosis

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Luis M Astudillo

2012-01-01

Full Text Available OBJECTIVE: We sought to ascertain predictors of Patient Prosthesis Mismatch, an independent predictor of mortality, in patients with aortic stenosis using bioprosthetic valves. METHOD: We analyzed 2,107 sequential surgeries. Patient Prosthesis Mismatch was calculated using the effective orifice area of the prosthesis divided by the patient's body surface area. We defined nonsignificant, moderate, and severe Patient Prosthesis Mismatch as effective orifice area indexes of .0.85 cm²/m, 0.85-0.66 cm²/m², and <0.65 cm²/m², respectively. RESULTS: A total of 311 bioprosthetic patients were identified. The incidence of nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 41%, 42, and 16%, respectively. Severe Patient Prosthesis Mismatch was significantly more prevalent in females (82%. In severe Patient Prosthesis Mismatch, the perfusion and the crossclamp times were considerably lower when compared with nonsignificant Patient Prosthesis Mismatch and moderate Patient Prosthesis Mismatch. Patients with severe Patient Prosthesis Mismatch had a significantly higher likelihood of spending time in the intensive care unit and a significantly longer length of stay in the hospital. Body surface area was not different in severe Patient Prosthesis Mismatch when compared with nonsignificant Patient Prosthesis Mismatch. In-hospital mortality in patients with nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 2.3%, 6.1%, and 8%, respectively. Minimally invasive surgery was significantly associated with moderate Patient Prosthesis Mismatch in 49% of the patients, but not with severe Patient Prosthesis Mismatch. CONCLUSION: Severe Patient Prosthesis Mismatch is more common in females, but not in those with minimal available body surface area. Though operative times were shorter in these patients, intensive care unit and hospital lengths of stay were longer. Surgeons and cardiologists should be cognizant of these clinical

A pneumatic Bionic Voice prosthesis-Pre-clinical trials of controlling the voice onset and offset.

Science.gov (United States)

Ahmadi, Farzaneh; Noorian, Farzad; Novakovic, Daniel; van Schaik, André

2018-01-01

Despite emergent progress in many fields of bionics, a functional Bionic Voice prosthesis for laryngectomy patients (larynx amputees) has not yet been achieved, leading to a lifetime of vocal disability for these patients. This study introduces a novel framework of Pneumatic Bionic Voice Prostheses as an electronic adaptation of the Pneumatic Artificial Larynx (PAL) device. The PAL is a non-invasive mechanical voice source, driven exclusively by respiration with an exceptionally high voice quality, comparable to the existing gold standard of Tracheoesophageal (TE) voice prosthesis. Following PAL design closely as the reference, Pneumatic Bionic Voice Prostheses seem to have a strong potential to substitute the existing gold standard by generating a similar voice quality while remaining non-invasive and non-surgical. This paper designs the first Pneumatic Bionic Voice prosthesis and evaluates its onset and offset control against the PAL device through pre-clinical trials on one laryngectomy patient. The evaluation on a database of more than five hours of continuous/isolated speech recordings shows a close match between the onset/offset control of the Pneumatic Bionic Voice and the PAL with an accuracy of 98.45 ±0.54%. When implemented in real-time, the Pneumatic Bionic Voice prosthesis controller has an average onset/offset delay of 10 milliseconds compared to the PAL. Hence it addresses a major disadvantage of previous electronic voice prostheses, including myoelectric Bionic Voice, in meeting the short time-frames of controlling the onset/offset of the voice in continuous speech.

21 CFR 888.3760 - Wrist joint carpal scaphoid polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint carpal scaphoid polymer prosthesis. 888.3760 Section 888.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... scaphoid polymer prosthesis. (a) Identification. A wrist joint carpal scaphoid polymer prosthesis is a one...

21 CFR 888.3750 - Wrist joint carpal lunate polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint carpal lunate polymer prosthesis. 888.3750 Section 888.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... lunate polymer prosthesis. (a) Identification. A wrist joint carpal lunate prosthesis is a one-piece...

21 CFR 888.3770 - Wrist joint carpal trapezium polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint carpal trapezium polymer prosthesis. 888.3770 Section 888.3770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... trapezium polymer prosthesis. (a) Identification. A wrist joint carpal trapezium polymer prosthesis is a one...

Reliability of change in lumbar MRI findings over time in patients with and without disc prosthesis - comparing two different image evaluation methods

International Nuclear Information System (INIS)

Berg, Linda; Espeland, Ansgar; Gjertsen, Oeivind; Hellum, Christian; Neckelmann, Gesche; Johnsen, Lars G.; Eide, Geir E.

2012-01-01

To assess the reliability of change in lumbar magnetic resonance imaging (MRI) findings evaluated retrospectively by direct comparison of images and by non-comparison. Pre-treatment and 2-year follow-up MRI was performed in 126 patients randomized to disc prosthesis surgery or non-surgical treatment. Two experienced radiologists independently evaluated progress and regress for Modic changes, disc findings, and facet arthropathy (FA) at L3/L4, L4/L5, and L5/S1, both by non-comparison and by comparison of initial and follow-up images. FA was evaluated at all levels, and other findings at non-operated levels. We calculated prevalence- and bias-adjusted kappa (PABAK) values for interobserver agreement. The impact of an adjacent prosthesis (which causes artefacts) and image evaluation method on PABAK was assessed using generalized estimating equations. Image comparison indicated good interobserver agreement on progress and regress (PABAK 0.63-1.00) for Modic changes, posterior high-intensity zone, disc height, and disc contour at L3-S1 and for nucleus pulposus signal and FA at L3/L4; and moderate interobserver agreement (PABAK 0.46-0.59) on decreasing nucleus signal and increasing FA at L4-S1. Image comparison indicated lower (but fair) interobserver agreement (PABAK 0.29) only for increasing FA at L5/S1 in patients with prosthesis in L4/L5 and/or L5/S1. An adjacent prosthesis had no overall impact on PABAK values (p ≥ 0.22). Comparison yielded higher PABAK values than non-comparison (p < 0.001). Regarding changes in lumbar MRI findings over time, comparison of images can provide moderate or good interobserver agreement, and better agreement than non-comparison. An adjacent prosthesis may not reduce agreement on change for most findings. (orig.)

A modified technique for retention of orbital prosthesis

Directory of Open Access Journals (Sweden)

Sameera R Shaikh

2011-01-01

Full Text Available An orbital defect (congenital or acquired causes severe facial asymmetry and disfigurement, which results in psychological and social disturbances to the patient. It becomes a challenging task for a maxillofacial prosthodontist to fabricate a prosthesis that replicates the healthy side of the face. Success of the prosthesis depends primarily on satisfactory retention of the same. This clinical report illustrates rehabilitation of a patient with an orbital defect by fabricating a hollow orbital prosthesis, utilizing anatomical undercuts for retention using an acrylic resin template relined by a resilient denture liner.

Communication Protocol for Advanced Prosthesis Components

OpenAIRE

Karnå, David

2007-01-01

It would be of great value for the prosthesis industry to achieve an open standard for communication in upper limb prostheses. Cooperation between NTNU and the University of New Brunswick has resulted in a functional requirements specification for such a standard, SCIP(Standardised Communication Interface in Prostheses). The special challenges for communication in a prosthesis system are possible noisy environments, high demands for light weight, safety for the user and the fact that devices ...

Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report

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Gayatri Shankaran

2016-08-01

Full Text Available Rapid prototyping (RP is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D model created in a computer aided design (CAD system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the cranio-maxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography.

Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report.

Science.gov (United States)

Shankaran, Gayatri; Deogade, Suryakant Chhagan; Dhirawani, Rajesh

2016-01-01

Rapid prototyping (RP) is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D) model created in a computer aided design (CAD) system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the craniomaxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography.

A Simple Technique for Accurate Transfer of Secondary Copings in a Tooth-Supported Telescopic Prosthesis.

Science.gov (United States)

Shankargouda, Swapnil B; Sidhu, Preena; Kardalkar, Swetha; Desai, Pooja M

2017-02-01

Residual ridge resorption is a rapid, progressive, irreversible, and inevitable process of bone resorption. Long-standing teeth and implants have been shown to have maintained the bone around them without resorption. Thus, overdenture therapy has been proven to be beneficial in situations where few remaining teeth are present. In addition to the various advantages seen with tooth-supported telescopic overdentures, a few shortcomings can also be expected, including unseating of the overdenture, increased bulk of the prosthesis, secondary caries, etc. The precise transfer of the secondary telescopic copings to maintain the spatial relationship, without any micromovement, remains the most critical step in ensuring the success of the tooth-supported telescopic prosthesis. Thus, a simple and innovative technique of splinting the secondary copings was devised to prevent distortion and micromovement and maintain its spatial relationship. © 2015 by the American College of Prosthodontists.

Metabolics of stair ascent with a powered transfemoral prosthesis.

Science.gov (United States)

Ledoux, E D; Lawson, B E; Shultz, A H; Bartlett, H L; Goldfarb, M

2015-01-01

This paper evaluates the effectiveness of a powered knee and ankle prosthesis for stair ascent through a metabolic assessment comparing energy expenditure of a single transfemoral amputee subject while ascending stairs with the powered prosthesis relative to his passive daily use device, as well as comparing the kinematics and kinetics obtained with the passive prosthesis to healthy biomechanics. The subject wore a portable system that measured pulmonary gaseous exchange rates of oxygen and carbon dioxide while he ascended stairs with each of the prostheses in alternating tests. The results indicated that the amputee's energy expenditure decreased by 32 percent while climbing with the powered prosthesis as compared to his passive one, and the kinematics and kinetics achieved were representative of healthy biomechanics.

A Multicenter, Prospective Trial to Assess the Safety and Performance of the Spinal Modulation Dorsal Root Ganglion Neurostimulator System in the Treatment of Chronic Pain

NARCIS (Netherlands)

A.L. Liem (Liong); M. Russo (Marc); F.J.P.M. Huygen (Frank); J.P. Van Buyten (Jean-Pierre); I. Smets (Ilse); P. Verrills (Paul); M. Cousins (Michael); C. Brooker (Charles); R. Levy (Richard); T. Deer (Timothy); J. Kramer (Jeffery)

2013-01-01

textabstractObjectives: This multicenter prospective trial was conducted to evaluate the clinical performance of a new neurostimulation system designed to treat chronic pain through the electrical neuromodulation of the dorsal root ganglia (DRG) neurophysiologically associated with painful regions

Brain-responsive neurostimulation in patients with medically intractable mesial temporal lobe epilepsy.

Science.gov (United States)

Geller, Eric B; Skarpaas, Tara L; Gross, Robert E; Goodman, Robert R; Barkley, Gregory L; Bazil, Carl W; Berg, Michael J; Bergey, Gregory K; Cash, Sydney S; Cole, Andrew J; Duckrow, Robert B; Edwards, Jonathan C; Eisenschenk, Stephan; Fessler, James; Fountain, Nathan B; Goldman, Alicia M; Gwinn, Ryder P; Heck, Christianne; Herekar, Aamar; Hirsch, Lawrence J; Jobst, Barbara C; King-Stephens, David; Labar, Douglas R; Leiphart, James W; Marsh, W Richard; Meador, Kimford J; Mizrahi, Eli M; Murro, Anthony M; Nair, Dileep R; Noe, Katherine H; Park, Yong D; Rutecki, Paul A; Salanova, Vicenta; Sheth, Raj D; Shields, Donald C; Skidmore, Christopher; Smith, Michael C; Spencer, David C; Srinivasan, Shraddha; Tatum, William; Van Ness, Paul C; Vossler, David G; Wharen, Robert E; Worrell, Gregory A; Yoshor, Daniel; Zimmerman, Richard S; Cicora, Kathy; Sun, Felice T; Morrell, Martha J

2017-06-01

Evaluate the seizure-reduction response and safety of mesial temporal lobe (MTL) brain-responsive stimulation in adults with medically intractable partial-onset seizures of mesial temporal lobe origin. Subjects with mesial temporal lobe epilepsy (MTLE) were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline. Safety was assessed based on reported adverse events. There were 111 subjects with MTLE; 72% of subjects had bilateral MTL onsets and 28% had unilateral onsets. Subjects had one to four leads placed; only two leads could be connected to the device. Seventy-six subjects had depth leads only, 29 had both depth and strip leads, and 6 had only strip leads. The mean follow-up was 6.1 ± (standard deviation) 2.2 years. The median percent seizure reduction was 70% (last observation carried forward). Twenty-nine percent of subjects experienced at least one seizure-free period of 6 months or longer, and 15% experienced at least one seizure-free period of 1 year or longer. There was no difference in seizure reduction in subjects with and without mesial temporal sclerosis (MTS), bilateral MTL onsets, prior resection, prior intracranial monitoring, and prior vagus nerve stimulation. In addition, seizure reduction was not dependent on the location of depth leads relative to the hippocampus. The most frequent serious device-related adverse event was soft tissue implant-site infection (overall rate, including events categorized as device-related, uncertain, or not device-related: 0.03 per implant year, which is not greater than with other neurostimulation devices). Brain-responsive stimulation represents a safe and effective treatment option for patients with medically intractable epilepsy, including patients with unilateral or bilateral MTLE who are not candidates for

Penile prosthesis implant: scientific advances and technological innovations over the last four decades.

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Chung, Eric

2017-02-01

Despite introduction of oral phosphodiesterase type 5 inhibitors and intracavernosal vasoactive agents, penile prosthesis implant remains a relevant and desired option with sales of penile prostheses continue to stay high, as many men became refractory to medical therapy and/or seeking a more effective and permanent therapy. There are two types of penile prosthesis implants: inflatable and non-inflatable types, and the inflatable penile implants can be subdivided into single-, two- and three-piece devices. Non-inflatable penile prosthesis (non-IPP) may be referred to as semi-rigid rod or malleable prosthesis. IPP is considered a superior option to malleable prosthesis as it produces penile rigidity and flaccidity that closely replicates a normal penile erectile function. Since the introduction of IPP by Scott in 1973, surgical landscape for penile prosthesis implantation has changed dramatically. Advances in prosthesis design, device technologies and surgical techniques have made penile prosthesis implant a more natural, durable and reliable device. The following article reviews the scientific advances and technological innovation in modern penile prosthesis implants over the last four decades.

A pneumatic Bionic Voice prosthesis-Pre-clinical trials of controlling the voice onset and offset.

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Farzaneh Ahmadi

Full Text Available Despite emergent progress in many fields of bionics, a functional Bionic Voice prosthesis for laryngectomy patients (larynx amputees has not yet been achieved, leading to a lifetime of vocal disability for these patients. This study introduces a novel framework of Pneumatic Bionic Voice Prostheses as an electronic adaptation of the Pneumatic Artificial Larynx (PAL device. The PAL is a non-invasive mechanical voice source, driven exclusively by respiration with an exceptionally high voice quality, comparable to the existing gold standard of Tracheoesophageal (TE voice prosthesis. Following PAL design closely as the reference, Pneumatic Bionic Voice Prostheses seem to have a strong potential to substitute the existing gold standard by generating a similar voice quality while remaining non-invasive and non-surgical. This paper designs the first Pneumatic Bionic Voice prosthesis and evaluates its onset and offset control against the PAL device through pre-clinical trials on one laryngectomy patient. The evaluation on a database of more than five hours of continuous/isolated speech recordings shows a close match between the onset/offset control of the Pneumatic Bionic Voice and the PAL with an accuracy of 98.45 ±0.54%. When implemented in real-time, the Pneumatic Bionic Voice prosthesis controller has an average onset/offset delay of 10 milliseconds compared to the PAL. Hence it addresses a major disadvantage of previous electronic voice prostheses, including myoelectric Bionic Voice, in meeting the short time-frames of controlling the onset/offset of the voice in continuous speech.

Automated estimation of hip prosthesis migration: a feasibility study

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Vandemeulebroucke, Jef; Deklerck, Rudi; Temmermans, Frederik; Van Gompel, Gert; Buls, Nico; Scheerlinck, Thierry; de Mey, Johan

2013-09-01

A common complication associated with hip arthoplasty is prosthesis migration, and for most cemented components a migration greater than 0.85 mm within the first six months after surgery, are an indicator for prosthesis failure. Currently, prosthesis migration is evaluated using X-ray images, which can only reliably estimate migrations larger than 5 mm. We propose an automated method for estimating prosthesis migration more accurately, using CT images and image registration techniques. We report on the results obtained using an experimental set-up, in which a metal prosthesis can be translated and rotated with respect to a cadaver femur, over distances and angles applied using a combination of positioning stages. Images are first preprocessed to reduce artefacts. Bone and prosthesis are extracted using consecutive thresholding and morphological operations. Two registrations are performed, one aligning the bones and the other aligning the prostheses. The migration is estimated as the difference between the found transformations. We use a robust, multi-resolution, stochastic optimization approach, and compare the mean squared intensity differences (MS) to mutual information (MI). 30 high-resolution helical CT scans were acquired for prosthesis translations ranging from 0.05 mm to 4 mm, and rotations ranging from 0.3° to 3° . For the translations, the mean 3D registration error was found to be 0.22 mm for MS, and 0.15 mm for MI. For the rotations, the standard deviation of the estimation error was 0.18° for MS, and 0.08° for MI. The results show that the proposed approach is feasible and that clinically acceptable accuracies can be obtained. Clinical validation studies on patient images will now be undertaken.

Availability of Dental Prosthesis Procedures in Brazilian Primary Health Care

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Maria Aparecida Gonçalves Melo Cunha

2018-01-01

Full Text Available Objectives. To describe dental prosthesis provision in the Brazilian public health service and report the performance of dental prosthesis procedures according to the Brazilian macroregions. Methods. A structured interview was conducted with senior-level health professionals from each of the 18,114 oral health teams (OHT. The dependent variables were performance of removable prostheses and prosthesis procedures, including provision of fixed prostheses by OHT. Descriptive statistics were produced together with performing a cluster analysis using SPSS version 19.0. Results. The manufacture of any type of prosthesis was done by a minority of OHT (43%. The most commonly provided types of dental prosthesis were removable full and partial dentures. Cluster 1 (teams that performed prosthesis procedures the most was composed of a smaller number of teams (n = 5,531, and Cluster 2 (composed of teams that do not perform prosthetics or that perform them in small amounts consisted of 12,583 teams. The geographic distribution of clusters reveals that the largest proportion of Cluster 1 teams is located in the Northeast (33.9% and Southeast (33.6%. Conclusions. A minority of OHT produce dental prostheses. There is an unequal geographical distribution of clusters.

Amputation and prosthesis implantation shape body and peripersonal space representations.

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Canzoneri, Elisa; Marzolla, Marilena; Amoresano, Amedeo; Verni, Gennaro; Serino, Andrea

2013-10-03

Little is known about whether and how multimodal representations of the body (BRs) and of the space around the body (Peripersonal Space, PPS) adapt to amputation and prosthesis implantation. In order to investigate this issue, we tested BR in a group of upper limb amputees by means of a tactile distance perception task and PPS by means of an audio-tactile interaction task. Subjects performed the tasks with stimulation either on the healthy limb or the stump of the amputated limb, while wearing or not wearing their prosthesis. When patients performed the tasks on the amputated limb, without the prosthesis, the perception of arm length shrank, with a concurrent shift of PPS boundaries towards the stump. Conversely, wearing the prosthesis increased the perceived length of the stump and extended the PPS boundaries so as to include the prosthetic hand, such that the prosthesis partially replaced the missing limb.

Management of long span partially edentulous maxilla with fixed removable denture prosthesis.

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Jeyavalan, Mahilan I; Narasimman, M; Venkatakrishnan, C J; Philip, Jacob M

2012-07-01

Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis.

Dosimetric influence of hip prosthesis during radiotherapeutic treatment

International Nuclear Information System (INIS)

Gschwind, R.; Buffard, E.; Masset, H.; Makovicka, L.; David, C.; David, C.; Buffard, E.

2008-01-01

As the population become aged, many patients with hip prosthesis are treated for a pelvic cancer. The recommended ballistic must avoid to pass in the prosthesis, but sometimes it is inevitable. So it is essential to quantify with accuracy the dose modifications linked to the presence of metallic implant. The aim of this study is to analyze by Monte Carlo method these modifications in simple and complex models (anthropomorphic phantom) which take into account the geometry and the composition of the prosthesis and its coatings. Then, this methodology was used to study the behaviour of a treatment planning system in theses extreme conditions. (authors)

Impact of hip prosthesis on dose distribution of pelvic radiotherapy

International Nuclear Information System (INIS)

Ren Jiangping; Zhang Songfang; Zhu Qibao; Guo Jianxin; Zha Yuanzi

2011-01-01

Objective: To study the scattering effect of Co-Cr-Mo hip prosthesis which was high Z material for patients undergoing pelvic irradiation. Methods: The hip prosthesis was set in water phantom (30 cm x 30 cm x 30 cm), determining points were chosen on the entrance side of both 6 MV and 10 MV beams at the distance of 0.5 cm, 1.0 cm, 2.0 cm to the hip prosthesis, and also on the exit side of both 6 MV and 10 MV beams at the distance of 3.0 cm, 5.0 cm, 7.0 cm to the hip prostheses. Dose behind the hip prosthesis at depths of 5.0 cm and 10.0 cm for 6 MV and 10 MV beams are also measured. Results: The dose deviation on the beams' entrance side is between 0 to 5.0%, the backscatter effect was more obviously with the higher energy beam. The dose deviation on the beams' exit side was between 21.6%-30.8%. With the same field size and depth, dose deviation becomes smaller when the beam energy was higher; while with the same energy and depth, dose deviation becomes smaller when the field size was bigger. Dose profiles behind the head of the hip prosthesis indicate obvious attenuation of the beam. Conclusions: Beam arrangements that avoid the prosthesis should be considered first or we should at least reduce the weight of the beam that pass through the prosthesis. (authors)

21 CFR 888.3810 - Wrist joint ulnar (hemi-wrist) polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint ulnar (hemi-wrist) polymer prosthesis. 888.3810 Section 888.3810 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-wrist) polymer prosthesis. (a) Identification. A wrist joint ulnar (hemi-wrist) polymer prosthesis...

21 CFR 888.3730 - Toe joint phalangeal (hemi-toe) polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Toe joint phalangeal (hemi-toe) polymer prosthesis. 888.3730 Section 888.3730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-toe) polymer prosthesis. (a) Identification. A toe joint phalangeal (hemi-toe) polymer prosthesis...

Extraspectral Imaging for Improving the Perceived Information Presented in Retinal Prosthesis

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Walid Al-Atabany

2018-01-01

Full Text Available Retinal prosthesis is steadily improving as a clinical treatment for blindness caused by retinitis pigmentosa. However, despite the continued exciting progress, the level of visual return is still very poor. It is also unlikely that those utilising these devices will stop being legally blind in the near future. Therefore, it is important to develop methods to maximise the transfer of useful information extracted from the visual scene. Such an approach can be achieved by digitally suppressing less important visual features and textures within the scene. The result can be interpreted as a cartoon-like image of the scene. Furthermore, utilising extravisual wavelengths such as infrared can be useful in the decision process to determine the optimal information to present. In this paper, we, therefore, present a processing methodology that utilises information extracted from the infrared spectrum to assist in the preprocessing of the visual image prior to conversion to retinal information. We demonstrate how this allows for enhanced recognition and how it could be implemented for optogenetic forms of retinal prosthesis. The new approach has been quantitatively evaluated on volunteers showing 112% enhancement in recognizing objects over normal approaches.

Penile Corporeal Reconstruction during Difficult Placement of a Penile Prosthesis

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Viet Q. Tran

2008-01-01

Full Text Available For some patients with impotence and concomitant severe tunical/corporeal tissue fibrosis, insertion of a penile prosthesis is the only option to restore erectile function. Closing the tunica over an inflatable penile prosthesis in these patients can be challenging. We review our previous study which included 15 patients with severe corporeal or tunical fibrosis who underwent corporeal reconstruction with autologous rectus fascia to allow placement of an inflatable penile prosthesis. At a mean follow-up of 18 months (range 12 to 64, all patients had a prosthesis that was functioning properly without evidence of separation, herniation, or erosion of the graft. Sexual activity resumed at a mean time of 9 weeks (range 8 to 10. There were no adverse events related to the graft or its harvest. Use of rectus fascia graft for coverage of a tunical defect during a difficult penile prosthesis placement is surgically feasible, safe, and efficacious.

Design and Control of a Pneumatically Actuated Transtibial Prosthesis.

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Zheng, Hao; Shen, Xiangrong

2015-04-01

This paper presents the design and control of a pneumatically actuated transtibial prosthesis, which utilizes a pneumatic cylinder-type actuator to power the prosthetic ankle joint to support the user's locomotion. The pneumatic actuator has multiple advantages over the traditional electric motor, such as light weight, low cost, and high power-to-weight ratio. The objective of this work is to develop a compact and lightweight transtibial prosthesis, leveraging the multiple advantages provided by this highly competitive actuator. In this paper, the design details of the prosthesis are described, including the determination of performance specifications, the layout of the actuation mechanism, and the calculation of the torque capacity. Through the authors' design calculation, the prosthesis is able to provide sufficient range of motion and torque capacity to support the locomotion of a 75 kg individual. The controller design is also described, including the underlying biomechanical analysis and the formulation of the finite-state impedance controller. Finally, the human subject testing results are presented, with the data indicating that the prosthesis is able to generate a natural walking gait and sufficient power output for its amputee user.

Prosthesis rejection in acquired major upper-limb amputees: a population-based survey.

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Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-07-01

To estimate the rates of primary and secondary prosthesis rejection in acquired major upper-limb amputees (ULAs), to describe the most frequently reported reasons for rejection and to estimate the influence of background factors on the risk of rejection. Cross-sectional study analysing population-based questionnaire data (n = 224). Effects were analysed by logistic regression analyses and Cox regression analyses. Primary prosthesis rejection was found in 4.5% whereas 13.4% had discontinued prosthesis use. The main reasons reported for primary non-wear were a perceived lack of need and discrepancies between perceived need and the prostheses available. The main reasons reported for secondary prosthesis rejection were dissatisfaction with prosthetic comfort, function and control. Primary prosthesis rejection was more likely in ULAs amputated at high age and in ULAs with proximal amputations. Secondary prosthesis rejection was more likely in proximal ULAs and in women. Clinicians should be aware of the increased risk of rejection in proximal ULAs, elderly ULAs and in women. Emphasising individual needs will probably facilitate successful prosthetic fitting. Improved prosthesis quality and individualised prosthetic training may increase long-term prosthesis use. Further studies of the effect of prosthetic training and of the reasons for rejection of different prosthetic types are suggested.

Management of long span partially edentulous maxilla with fixed removable denture prosthesis

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Mahilan I Jeyavalan

2012-01-01

Full Text Available Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis.

The Appropriate Use of Neurostimulation of the Spinal Cord and Peripheral Nervous System for the Treatment of Chronic Pain and Ischemic Diseases : The Neuromodulation Appropriateness Consensus Committee

NARCIS (Netherlands)

Deer, Timothy R.; Mekhail, Nagy; Provenzano, David; Pope, Jason; Krames, Elliot; Leong, Michael; Levy, Robert M.; Abejon, David; Buchser, Eric; Burton, Allen; Buvanendran, Asokumar; Candido, Kenneth; Caraway, David; Cousins, Michael; de Jongste, Micheal; Diwan, Sudhir; Eldabe, Sam; Gatzinsky, Kliment; Foreman, Robert D.; Hayek, Salim; Kim, Philip; Kinfe, Thomas; Kloth, David; Kumar, Krishna; Rizvi, Syed; Lad, Shivanand P.; Liem, Liong; Linderoth, Bengt; Mackey, Sean; McDowell, Gladstone; McRoberts, Porter; Poree, Lawrence; Prager, Joshua; Raso, Lou; Rauck, Richard; Russo, Marc; Simpson, Brian; Slavin, Konstantin; Staats, Peter; Stanton-Hicks, Michael; Verrills, Paul; Wellington, Joshua; Williams, Kayode; North, Richard

Introduction: The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb ischemia, and refractory angina and recommended

21 CFR 872.3970 - Interarticular disc prosthesis (interpositional implant).

Science.gov (United States)

2010-04-01

... implant). 872.3970 Section 872.3970 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc prosthesis...

Reading visual braille with a retinal prosthesis.

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Lauritzen, Thomas Z; Harris, Jordan; Mohand-Said, Saddek; Sahel, Jose A; Dorn, Jessy D; McClure, Kelly; Greenberg, Robert J

2012-01-01

Retinal prostheses, which restore partial vision to patients blinded by outer retinal degeneration, are currently in clinical trial. The Argus II retinal prosthesis system was recently awarded CE approval for commercial use in Europe. While retinal prosthesis users have achieved remarkable visual improvement to the point of reading letters and short sentences, the reading process is still fairly cumbersome. This study investigates the possibility of using an epiretinal prosthesis to stimulate visual braille as a sensory substitution for reading written letters and words. The Argus II retinal prosthesis system, used in this study, includes a 10 × 6 electrode array implanted epiretinally, a tiny video camera mounted on a pair of glasses, and a wearable computer that processes the video and determines the stimulation current of each electrode in real time. In the braille reading system, individual letters are created by a subset of dots from a 3 by 2 array of six dots. For the visual braille experiment, a grid of six electrodes was chosen out of the 10 × 6 Argus II array. Groups of these electrodes were then directly stimulated (bypassing the camera) to create visual percepts of individual braille letters. Experiments were performed in a single subject. Single letters were stimulated in an alternative forced choice (AFC) paradigm, and short 2-4-letter words were stimulated (one letter at a time) in an open-choice reading paradigm. The subject correctly identified 89% of single letters, 80% of 2-letter, 60% of 3-letter, and 70% of 4-letter words. This work suggests that text can successfully be stimulated and read as visual braille in retinal prosthesis patients.

Testicular prosthesis: Patient satisfaction and sexual dysfunctions in testis cancer survivors.

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Catanzariti, Francesco; Polito, Benedetta; Polito, Massimo

2016-10-05

We studied patient satisfaction about sexual activity after prosthesis implantation using validated questionnaires with the aim to discover if testicular prosthesis could be responsible of sexual dysfunctions (erectile dysfunction or premature ejaculation). We evaluated a total of 67 men who underwent radical orchiectomy for testicular cancer and a silicon testicular prosthesis implantation from January 2008 to June 2014 at our Hospital. These patients completed 5 validated questionnaires the day before orchiectomy and 6 months after surgery: the International Index of Erectile Function 5 (IIEF5), the Premature Ejaculation Diagnostic Tool (PEDT), the Body Exposure during Sexual Activities Questionnaire (BESAQ), the Body-Esteem Scale and the Rosenberg Self- Esteem Scale. We also evaluated 6 months after surgery any defects of the prosthesis complained by the patients. The questionnaires completed by patients didn't show statistically significant changes for erectile dysfunction (p > 0.05) and premature ejaculation (p > 0.05). On the contrary the psychological questionnaires showed statistically significant change for the BESAQ (p < 0.001) and the Body Esteem Scale (p < 0.001), but not for the Rosenberg Self-Esteem Scale (p > 0,05). A total of 15 patients (22.37%) were dissatisfied about the prosthesis: the most frequent complaint (8 patients; 11.94%) was that the prosthesis was firmer than the normal testis. Testicular prosthesis implantation is a safe surgical procedure that should be always proposed before orchiectomy for cancer of the testis. The defects complained by patients with testicular prosthesis are few, they don't influence sexual activity and they aren't able to cause erectile dysfunction or premature ejaculation.

Nasal prosthesis for a patient with xeroderma pigmentosum

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Suresh Kumar

2013-01-01

Full Text Available Acquired facial defects caused by extirpation of neoplasms, congenital malformations or traumatic injury results in a huge functional, cosmetic and psychological handicap in those patients. These defects can be restored by facial prosthesis using different materials and retention methods to achieve a lifelike appearance and function. This clinical report describes a treatment schedule using silicone nasal prosthesis, which is mechanically retained for a patient who has undergone a partial rhinectomy due to basal cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of patient with a mechanically retained design using a spectacle glass frame without any prosthetic adhesives so that the patient is more comfortable and confident to resume daily activities.

Systematic analysis and experiment of inductive coupling and induced voltage for inductively coupled wireless implantable neurostimulator application

International Nuclear Information System (INIS)

Xue, Ning; Cho, Sung-Hoon; Chang, Sung-Pil; Lee, Jeong-Bong

2012-01-01

The main strategy for wireless power transfer to implantable devices is to use inductive coupling technology. The induced voltage of implanted devices highly depends on factors such as mutual inductance between the external transmitter coil and the receiver coil, quality factor of the receiver circuit and operation frequency. In this paper, the mutual inductance under a variety of geometries of external coil and under the condition of different vertical distances, lateral displacements and angular misalignments between two coils were theoretically calculated and simulated. To ascertain the condition of maximum power transmission for certain coils’ position requirements, an LC tank (2.7 mm × 2 mm) consisting of a microfabricated gold inductor coil and a small surface mounted capacitor was designed and fabricated as the telemetric part of a neurostimulator. The induced voltage of the LC tank was measured in both air and artificial tissue media under different sizes of power coil and operation frequencies. As a result, the optimum size of a transmitter coil is selected to be of 4 mm inner radius with six turns of coil, while the whole coupling system operates at 94 MHz resonant frequency within 5–11 mm vertical distance, 0–4 mm lateral and 0°–50° angular misalignment between two coils. With the change of the above coils’ positions, the measured induced voltage drops within 30%, satisfying the surgical requirement for neurostimulator implantation. (paper)

99m technetium-MDP bone scintigraphy in evaluation of painful joint prosthesis

International Nuclear Information System (INIS)

Milosevic, D.; Jaukovic, M.; Jaukovic, Lj.; Ajdinovic, B.

2004-01-01

In addition of clinical evaluation and x-ray radiography, the diagnosis of a loose joint prosthesis is often made by nuclear medicine imaging techniques. Differentiation between loosening and infected prosthesis is important for better treatment of those patients. Aim: The aim of this study was to reevaluate the scintigraphic patterns in patients with painful hip of knee arthroplasty. Material and Method: From 1996. to 2003. forty patients aged 49-78 years were referred for evaluation of possible loosening/infection joint prosthesis: 36 pts with 39 total/ partial hip prosthesis, 1 pt with knee prosthesis and 3 pts with history of previously extracted hip prosthesis due to infection. Whole body acquisition had been performed with a single head gamma camera three hours after the injection of 740 MBq 99m Tc-MDP. Scans were classified as: positive for loosening if abnormal uptake was shown at the tip of the prosthesis; positive for infection if diffuse abnormal uptake was shown around the implant; negative and indeterminate scans. Scintigraphic findings were compared to clinical follow up, histology or cultures. Results: Positive findings were found in 17 bone scans strongly suggesting loosening in 10 cases, infection of prosthesis in 4 cases and both loosening/infection in 3 cases. Bone scintigraphy was normal in 11pts. Scans of three pts with previously extracted hip prosthesis and scheduled for reimplatation, showed inhomogeneously and mildly increased uptake in femur. Most of scans classified as indeterminate (n=12) showed slightly increased tracer uptake in region of acetabular roof, greater or lesser tho chanter, suggesting bone remodeling due to the presence of implant, rather than loosening. Conclusion: 99m Tc-MDP bone scintigraphy had a significant role in assessing the painful joint prosthesis. Complementary diagnostic procedures should be considered in indeterminate scintiscans. (authors)

Control and Evaluation of a Powered Transfemoral Prosthesis for Stair Ascent.

Science.gov (United States)

Ledoux, Elissa D; Goldfarb, Michael

2017-07-01

This paper assesses the metabolic effort exerted by three transfemoral amputees, when using a powered knee and ankle prosthesis for stair ascent, relative to ascending stairs with passive knee and ankle prostheses. The paper describes a controller that provides step-over stair ascent behavior reflective of healthy stair ascent biomechanics, and describes its implementation in a powered prosthesis prototype. Stair ascent experiments were performed with three unilateral transfemoral amputee subjects, comparing the oxygen consumption required to ascend stairs using the powered prosthesis (with a step-over gait), relative to using their daily-use energetically passive prostheses (with a step-to gait). Results indicate on average a 24% reduction in oxygen consumption and a 30% reduction in stair ascent timewhen using the powered prosthesis, relative to when using the passive prostheses. All subjects expressed a strong preference for ascending stairs using the powered prosthesis.

Ultrasound Guidance Versus Peripheral Neurostimulation for Brachial Plexus Block Anesthesia with Axillary Approach and Multiple Injection Technique

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Lazar Alexandra

2017-09-01

Full Text Available Introduction: There are several approaches for brachial plexus anesthesia: supraclavicular, infraclavicular, interscalenic and axillary. Out of these, the axillary approach is considered to be the safest because of the low risk of lesioning the adjacent structures, low risk of phrenic nerve blockade or of producing an iatrogenic pneumothorax. The block can be performed by one single injection at the site, by two injections or by several injection, among each nerve of the plexus. Ultrasound was introduced in regional anesthesia since 1978, being used initially as an auxiliary method to peripheral neurostimulator.

Neurostimulation options for failed back surgery syndrome: The need for rational and objective measurements. Proposal of an international clinical network using an integrated database and health economic analysis: the PROBACK network.

Science.gov (United States)

Rigoard, P; Slavin, K

2015-03-01

In the context of failed back surgery syndrome (FBSS) treatment, the current practice in neurostimulation varies from center-to-center and most clinical decisions are based on an individual diagnosis. Neurostimulation evaluation tools and pain relief assessment are of major concern, as they now constitute one of the main biases of clinical trials. Moreover, the proliferation of technological devices, in a fertile and unsatisfied market, fosters and only furthers the confusion. There are three options available to apply scientific debates to our daily neurostimulation practice: intentional ignorance, standardized evidence-based practice or alternative data mining approach. In view of the impossibility of conducting multiple randomized clinical trials comparing various devices, one by one, the proposed concept would be to redefine the indications and the respective roles of the various spinal cord and peripheral nerve stimulation devices with large-scale computational modeling/data mining approach, by conducting a multicenter prospective database registry, supported by a clinician's global network called "PROBACK". We chose to specifically analyze 6 parameters: device coverage performance/coverage selectivity/persistence of the long-term electrical response (technical criteria) and comparative mapping of patient pain relief/persistence of the long-term clinical response/safety and complications occurrence (clinical criteria). Two types of analysis will be performed: immediate analysis (including cost analysis) and computational analysis, i.e. demonstration of the robustness of certain correlations of variables, in order to extract response predictors. By creating an international prospective database, the purpose of the PROBACK project was to set up a process of extraction and comparative analysis of data derived from the selection, implantation and follow-up of FBSS patients candidates for implanted neurostimulation. This evaluation strategy should help to change

Prosthetic rehabilitation of large mid-facial defect with magnet-retained silicone prosthesis

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Kirti Jajoo Shrivastava

2015-01-01

Full Text Available Rehabilitation of maxillofacial defect patients is a challenging task. The most common prosthetic treatment problem with such patients is, getting adequate retention, stability, and support. In cases of large maxillofacial defect, movement of the prosthesis is inevitable. The primary objectives in rehabilitating the maxillofacial defect patients are to restore the function of mastication, deglutition, speech, and to achieve normal orofacial appearance. This clinical report describes maxillofacial prosthetic rehabilitation of large midfacial defect including orbit along with its contents, zygoma and soft tissues including half of the nose, cheeks, upper lip of left side, accompanying postsurgical microstomia and orofacial communication, which resulted from severe fungal infection mucormycosis. The defect in this case was restored with magnet retained two piece maxillofacial prosthesis having hollow acrylic resin framework and an overlying silicone facial prosthesis. The retention of prosthesis was further enhanced with the use of spectacles. This type of combination prosthesis enhanced the cosmesis and functional acceptability of prosthesis.

Function of obturator prosthesis after maxillectomy and prosthetic obturator rehabilitation

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Cheng Chen

2016-04-01

Full Text Available ABSTRACT INTRODUCTION: Maxillary defects are usually rehabilitated by a prosthetic obturator. OBJECTIVE: This study aimed to evaluate the functioning of obturators prosthesis in patients with unilateral defects after maxillectomy. METHODS: Of 49 patients, 28 underwent to maxillectomy as a result of tumor ablative surgery, and acquired unilateral maxillary defects. Evaluation of the function was performed by applying the Obturator Functional Scale (OFS. RESULTS: From a total of 49 patients, 28 were treated as follows: 9 with a conventional retained obturator prosthesis (COP, 11 (39% with an enhanced retentive obturator prosthesis with stud attachment (POP and 8 (28% with an enhanced retentive obturator prosthesis with magnetic attachment (POM. The mean OFS score was 80. Scores on functions of speech, swallowing and chewing reached statistical significances (p < 0.05 among these three subgroups. Comparing COP and MOP groups, the scores of OFS in the domains of "Speech-ability to speak in public" and "Swallowing-leakage with liquids" were significantly higher in AOP group. Comparing COP group, the scores of OFS in "Swallowing-leakage with solid" and "Chewing/eating" domains were increased significantly (p < 0.05 both in MOP and AOP groups. CONCLUSION: Obturator prosthesis improves oral function of patients after maxillary defects; the retention of the obturator prosthesis enhanced by the addition of attachments showed more benefits in oral function.

Testicular prosthesis: Patient satisfaction and sexual dysfunctions in testis cancer survivors

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Francesco Catanzariti

2016-10-01

Full Text Available Purpose: We studied patient satisfaction about sexual activity after prosthesis implantation using validated questionnaires with the aim to discover if testicular prosthesis could be responsible of sexual dysfunctions (erectile dysfunction or premature ejaculation. Materials and Methods: We evaluated a total of 67 men who underwent radical orchiectomy for testicular cancer and a silicon testicular prosthesis implantation from January 2008 to June 2014 at our Hospital. These patients completed 5 validated questionnaires the day before orchiectomy and 6 months after surgery: the International Index of Erectile Function 5 (IIEF5, the Premature Ejaculation Diagnostic Tool (PEDT, the Body Exposure during Sexual Activities Questionnaire (BESAQ, the Body-Esteem Scale and the Rosenberg Self- Esteem Scale. We also evaluated 6 months after surgery any defects of the prosthesis complained by the patients. Results: The questionnaires completed by patients didn’t show statistically significant changes for erectile dysfunction (p > 0.05 and premature ejaculation (p > 0.05. On the contrary the psychological questionnaires showed statistically significant change for the BESAQ (p < 0.001 and the Body Esteem Scale (p < 0.001, but not for the Rosenberg Self-Esteem Scale (p > 0,05. A total of 15 patients (22.37% were dissatisfied about the prosthesis: the most frequent complaint (8 patients; 11.94% was that the prosthesis was firmer than the normal testis. Conclusions: Testicular prosthesis implantation is a safe surgical procedure that should be always proposed before orchiectomy for cancer of the testis. The defects complained by patients with testicular prosthesis are few, they don’t influence sexual activity and they aren’t able to cause erectile dysfunction or premature ejaculation.

An animal model to evaluate skin-implant-bone integration and gait with a prosthesis directly attached to the residual limb.

Science.gov (United States)

Farrell, Brad J; Prilutsky, Boris I; Kistenberg, Robert S; Dalton, John F; Pitkin, Mark

2014-03-01

Despite the number of advantages of bone-anchored prostheses, their use in patients is limited due to the lack of complete skin-implant integration. The objective of the present study was to develop an animal model that would permit both detailed investigations of gait with a bone-anchored limb prosthesis and histological analysis of the skin-implant-bone interface after physiological loading of the implant during standing and walking. Full-body mechanics of walking in two cats were recorded and analyzed before and after implantation of a percutaneous porous titanium pylon into the right tibia and attachment of a prosthesis. The rehabilitation procedures included initial limb casting, progressively increasing loading on the implant, and standing and locomotor training. Detailed histological analysis of bone and skin ingrowth into implant was performed at the end of the study. The two animals adopted the bone-anchored prosthesis for standing and locomotion, although loads on the prosthetic limb during walking decreased by 22% and 62%, respectively, 4months after implantation. The animals shifted body weight to the contralateral side and increased propulsion forces by the contralateral hindlimb. Histological analysis of the limb implants demonstrated bone and skin ingrowth. The developed animal model to study prosthetic gait and tissue integration with the implant demonstrated that porous titanium implants may permit bone and skin integration and prosthetic gait with a bone-anchored prosthesis. Future studies with this model will help optimize the implant and prosthesis properties. Copyright © 2013 Elsevier Ltd. All rights reserved.

Use of Powered Prosthesis for Children with Upper Limb Deficiency at Hyogo Rehabilitation Center.

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Mitsunori Toda

Full Text Available There has been no research investigating the use of powered prosthetic for children in Japan.To gain better insight into the state of powered prosthesis usage and identify a ratio of rejection among children.Subjects were 37 unilateral below elbow amputees between the ages of 0 and 16 at the time of their first experienced fitting with a powered prosthesis at our Center. The information was collected from medical records and through face-to-face interviews, and we examined rejection rate and the factors affecting the use of powered prosthesis.The rate of discontinuation was 21.6% as 8 of the 37 children stopped using powered prosthesis. All of them were fitted their prosthesis after 2 years of age, and they rejected prosthesis between 5 to 19 years. We found that the level of amputation had no influence on the use of a powered prosthesis.Children fitted before 2 years of age tend to accept their powered prosthesis than those fitted after 2 years. Multidisciprinary team approach, adequate rehabilitation, detailed follow-up and involvement of parents are quite important for introducing powered prosthesis for children.

Changes in performance over time while learning to use a myoelectric prosthesis

NARCIS (Netherlands)

Bouwsema, Hanneke; van der Sluis, Corry K.; Bongers, Raoul M.

2014-01-01

Background: Training increases the functional use of an upper limb prosthesis, but little is known about how people learn to use their prosthesis. The aim of this study was to describe the changes in performance with an upper limb myoelectric prosthesis during practice. The results provide a basis

Design of a power-asymmetric actuator for a transtibial prosthesis.

Science.gov (United States)

Bartlett, Harrison L; Lawson, Brian E; Goldfarb, Michael

2017-07-01

This paper presents the design and characterization of a power-asymmetric actuator for a transtibial prosthesis. The device is designed to provide the combination of: 1) joint locking, 2) high power dissipation, and 3) low power generation. This actuator functionality allows for a prosthesis to be designed with minimal mass and power consumption relative to a fully-powered robotic prosthesis while maintaining much of the functionality necessary for activities of daily living. The actuator achieves these design characteristics while maintaining a small form factor by leveraging a combination of electromechanical and hydraulic components. The design of the actuator is described herein, and results of an experimental characterization are provided that indicate that the actuator is capable of providing the functional capabilities required of an ankle prosthesis in a compact and lightweight package.

Embedded System for Prosthetic Control Using Implanted Neuromuscular Interfaces Accessed Via an Osseointegrated Implant.

Science.gov (United States)

Mastinu, Enzo; Doguet, Pascal; Botquin, Yohan; Hakansson, Bo; Ortiz-Catalan, Max

2017-08-01

Despite the technological progress in robotics achieved in the last decades, prosthetic limbs still lack functionality, reliability, and comfort. Recently, an implanted neuromusculoskeletal interface built upon osseointegration was developed and tested in humans, namely the Osseointegrated Human-Machine Gateway. Here, we present an embedded system to exploit the advantages of this technology. Our artificial limb controller allows for bioelectric signals acquisition, processing, decoding of motor intent, prosthetic control, and sensory feedback. It includes a neurostimulator to provide direct neural feedback based on sensory information. The system was validated using real-time tasks characterization, power consumption evaluation, and myoelectric pattern recognition performance. Functionality was proven in a first pilot patient from whom results of daily usage were obtained. The system was designed to be reliably used in activities of daily living, as well as a research platform to monitor prosthesis usage and training, machine-learning-based control algorithms, and neural stimulation paradigms.

Cranioplasty prosthesis manufacturing based on reverse engineering technology

Science.gov (United States)

Chrzan, Robert; Urbanik, Andrzej; Karbowski, Krzysztof; Moskała, Marek; Polak, Jarosław; Pyrich, Marek

2012-01-01

Summary Background Most patients with large focal skull bone loss after craniectomy are referred for cranioplasty. Reverse engineering is a technology which creates a computer-aided design (CAD) model of a real structure. Rapid prototyping is a technology which produces physical objects from virtual CAD models. The aim of this study was to assess the clinical usefulness of these technologies in cranioplasty prosthesis manufacturing. Material/Methods CT was performed on 19 patients with focal skull bone loss after craniectomy, using a dedicated protocol. A material model of skull deficit was produced using computer numerical control (CNC) milling, and individually pre-operatively adjusted polypropylene-polyester prosthesis was prepared. In a control group of 20 patients a prosthesis was manually adjusted to each patient by a neurosurgeon during surgery, without using CT-based reverse engineering/rapid prototyping. In each case, the prosthesis was implanted into the patient. The mean operating times in both groups were compared. Results In the group of patients with reverse engineering/rapid prototyping-based cranioplasty, the mean operating time was shorter (120.3 min) compared to that in the control group (136.5 min). The neurosurgeons found the new technology particularly useful in more complicated bone deficits with different curvatures in various planes. Conclusions Reverse engineering and rapid prototyping may reduce the time needed for cranioplasty neurosurgery and improve the prosthesis fitting. Such technologies may utilize data obtained by commonly used spiral CT scanners. The manufacturing of individually adjusted prostheses should be commonly used in patients planned for cranioplasty with synthetic material. PMID:22207125

Long-Term Symptoms Onset and Heterotopic Bone Formation around a Total Temporomandibular Joint Prosthesis: a Case Report

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Luca Guarda-Nardini

2014-04-01

Full Text Available Background: The literature on total alloplastic temporomandibular joint (TMJ reconstructions is encouraging, and studies on total alloplastic TMJ replacements outcomes showed acceptable improvements in terms of both pain levels and jaw function. Nevertheless, some adverse events, such as heterotopic bone formation around the implanted prosthesis, may occur. In consideration of that, the present manuscript describes a case of heterotopic bone formation around a total temporomandibular joint prosthesis, which occurred several years after the implant. Methods: The present manuscript describes a case of heterotopic bone formation around a total TMJ prosthesis, which occurred several years after the implant in patients, who previously underwent multiple failed TMJ surgeries. Results: Ten years after the surgical TMJ replacement to solve an ankylotic bone block, the patient came to our attention again referring a progressive limitation in mouth opening. A computerized tomography showed evidence of marked heterotopic bone formation in the medial aspects of the joint, where a new-born ankylotic block occupied most part of the gap created by resecting the coronoid process at the time of the TMJ prosthesis insertion. Conclusions: Despite this adverse event has been sometimes described in the literature, this is the first case in which its occurrence happened several years after the temporomandibular joint replacement. It can be suggested that an accurate assessment of pre-operative risk factors for re-ankylosis (e.g., patients with multiple failed temporomandibular joint surgeries and within-intervention prevention (e.g., strategies to keep the bone interfaces around the implant separated should be better standardized and define in future studies.

Function of obturator prosthesis after maxillectomy and prosthetic obturator rehabilitation.

Science.gov (United States)

Chen, Cheng; Ren, Wenhao; Gao, Ling; Cheng, Zheng; Zhang, Linmei; Li, Shaoming; Zhi, Pro Ke-qian

2016-01-01

Maxillary defects are usually rehabilitated by a prosthetic obturator. This study aimed to evaluate the functioning of obturators prosthesis in patients with unilateral defects after maxillectomy. Of 49 patients, 28 underwent to maxillectomy as a result of tumor ablative surgery, and acquired unilateral maxillary defects. Evaluation of the function was performed by applying the Obturator Functional Scale (OFS). From a total of 49 patients, 28 were treated as follows: 9 with a conventional retained obturator prosthesis (COP), 11 (39%) with an enhanced retentive obturator prosthesis with stud attachment (POP) and 8 (28%) with an enhanced retentive obturator prosthesis with magnetic attachment (POM). The mean OFS score was 80. Scores on functions of speech, swallowing and chewing reached statistical significances (p<0.05) among these three subgroups. Comparing COP and MOP groups, the scores of OFS in the domains of "Speech-ability to speak in public" and "Swallowing-leakage with liquids" were significantly higher in AOP group. Comparing COP group, the scores of OFS in "Swallowing-leakage with solid" and "Chewing/eating" domains were increased significantly (p<0.05) both in MOP and AOP groups. Obturator prosthesis improves oral function of patients after maxillary defects; the retention of the obturator prosthesis enhanced by the addition of attachments showed more benefits in oral function. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Design and Characterization of a Quasi-Passive Pneumatic Foot-Ankle Prosthesis.

Science.gov (United States)

Lee, Jeffrey D; Mooney, Luke M; Rouse, Elliott J

2017-07-01

The majority of commercially available passive prosthetic feet are not capable of providing joint mechanics that match that of the intact human ankle. Due to their cantilever design, their stiffness characteristics contrast with what has been observed in the biological ankle, namely, an increase in stiffness during the stance phase of walking. In this paper, we introduce the design and control of a pneumatic foot-ankle prosthesis that attempts to provide biomimetic mechanics. The prosthesis is comprised of a pneumatic cylinder in series with a fiberglass leaf spring, and a solenoid valve to control the flow of air between the two sides of the cylinder. The solenoid valve acts as a mechanical clutch, enabling resetting of the ankle's equilibrium position. By adjusting the pressure inside the cylinder, the prosthesis can be customized to provide a range of ankle mechanics. A mechanical testing machine is used to compare the torque-angle curve of the pneumatic prosthesis with a low-profile passive prosthetic foot. Finally, data are presented of one transtibial amputee walking with the prosthesis at 1.2 m/s. The testing shows that the pneumatic prosthesis is capable of providing an appropriate range of motion as well a maximum torque of 94 Nm, while returning approximately 11.5 J of energy.

Doppler derived gradient of ST Jude Mechanical Prosthesis, early postoperative assessment

International Nuclear Information System (INIS)

Shaikh, A.H.; Hanif, B.; Adil, A.; Hashimi, S.; Qazi, H.A.; Mujtaba, I.

2010-01-01

Objective: To determine the doppler derived mean gradients of St Jude mechanical prosthesis in early postoperative period in patients undergoing valve replacement at a tertiary care cardiac centre. Methods: Medical records of 190 consecutive patients who underwent 233 mitral, aortic or dual (mitral and aortic) valve replacement by St Jude bileaflet mechanical prosthesis at Tabba Heart Institute, between March 2006 to December 2008 were reviewed. Doppler derived mean gradients were assessed predischarge and recorded. Results: There were 98 (51.5%) males and 92 (48.5%) females in the study cohort. The mean age was 40 +- 14 years. Of the total, 101 (53%) had mitral, 46 (24.2%) had aortic and 43 (22.6%) patients had dual valve replacement. Doppler derived mean gradient was assessed across 144 mitral and 89 aortic St Jude mechanical prosthesis. Doppler derived mean gradient for St Jude mitral prosthesis was 3.5 mm Hg and for St Jude aortic prosthesis was 10.2 mm Hg. Conclusions: The study determines baseline gradients across mitral and aortic St Jude mechanical prosthesis in our population. These can be used as reference gradients to assess St Jude prosthetic valve function in patients who did not have early postoperative doppler assessment. (author)

The reverse shoulder prosthesis: a review of imaging features and complications

Energy Technology Data Exchange (ETDEWEB)

McFarland, Edward G.; Sanguanjit, Prakasit; Tasaki, Atsushi [Johns Hopkins University, Department of Orthopedic Surgery, Lutherville, MD (United States); Keyurapan, Ekavit [Mahidol University, Department of Orthopaedic Surgery, Bangkok (Thailand); Fishman, Elliot K.; Fayad, Laura M. [Johns Hopkins Medical Institutions, Johns Hopkins University, Department of Radiology and Radiological Sciences, Baltimore, MD (United States)

2006-07-15

The reverse shoulder prosthesis is a prosthesis that has been in clinical use in Europe since 1985 and was approved for use in the United States in 2004. This unique prosthesis has a baseplate attached to the glenoid, which holds a spherical component, while the humeral component includes a polyethylene insert that is flat. This design is the ''reverse'' configuration of that seen with a conventional arthroplasty, in which the spherical component is part of the humeral component. The indications for the reverse prosthesis are: (1) painful arthritis associated with irreparable rotator cuff tears (cuff tear arthropathy), (2) failed hemiarthroplasty with irreparable rotator cuff tears, (3) pseudoparalysis due to massive, irreparable rotator cuff tears, (4) some reconstructions after tumor resection, and (5) some fractures of the shoulder not repairable or reconstructable with other techniques. This prosthesis can produce a significant reduction in pain and some improvement in function for most of the indications mentioned. However, the unique configuration and the challenge of its insertion can result in a high incidence of a wide variety of unusual complications. Some of these complications, such as dislocation of the components, are similar to conventional shoulder replacement. Other complications, such as notching of the scapula and acromial stress fractures, are unique to this prosthesis. (orig.)

The reverse shoulder prosthesis: a review of imaging features and complications

International Nuclear Information System (INIS)

McFarland, Edward G.; Sanguanjit, Prakasit; Tasaki, Atsushi; Keyurapan, Ekavit; Fishman, Elliot K.; Fayad, Laura M.

2006-01-01

The reverse shoulder prosthesis is a prosthesis that has been in clinical use in Europe since 1985 and was approved for use in the United States in 2004. This unique prosthesis has a baseplate attached to the glenoid, which holds a spherical component, while the humeral component includes a polyethylene insert that is flat. This design is the ''reverse'' configuration of that seen with a conventional arthroplasty, in which the spherical component is part of the humeral component. The indications for the reverse prosthesis are: (1) painful arthritis associated with irreparable rotator cuff tears (cuff tear arthropathy), (2) failed hemiarthroplasty with irreparable rotator cuff tears, (3) pseudoparalysis due to massive, irreparable rotator cuff tears, (4) some reconstructions after tumor resection, and (5) some fractures of the shoulder not repairable or reconstructable with other techniques. This prosthesis can produce a significant reduction in pain and some improvement in function for most of the indications mentioned. However, the unique configuration and the challenge of its insertion can result in a high incidence of a wide variety of unusual complications. Some of these complications, such as dislocation of the components, are similar to conventional shoulder replacement. Other complications, such as notching of the scapula and acromial stress fractures, are unique to this prosthesis. (orig.)

Association between dental prosthesis need, nutritional status and quality of life of elderly subjects

DEFF Research Database (Denmark)

Pillai, Rajath; Mathur, Vijay Prakash; Jain, Veena

2015-01-01

clinic were recruited in the study. Mini-nutritional assessment (MNA), geriatric oral health assessment (GOHAI) indices, prosthesis need according to WHO criteria, and prosthesis want was recorded along with age, gender, socioeconomic status and posterior occluding pair. RESULTS: Significant associations......To determine the effect of prosthesis need on nutritional status and oral health-related quality of life (OHrQoL) in elderly and to check the disparity between prosthesis need and prosthesis want in the Indian elderly. METHODS: A total of 946 geriatric participants reporting to a geriatric medicine...

Smartphone supported upper limb prosthesis

Directory of Open Access Journals (Sweden)

Hepp D.

2015-09-01

Full Text Available State of the art upper limb prostheses offer up to six active DoFs (degrees of freedom and are controlled using different grip patterns. This low number of DoFs combined with a machine-human-interface which does not provide control over all DoFs separately result in a lack of usability for the patient. The aim of this novel upper limb prosthesis is both offering simplified control possibilities for changing grip patterns depending on the patients’ priorities and the improvement of grasp capability. Design development followed the design process requirements given by the European Medical Device Directive 93/42 ECC and was structured into the topics mechanics, software and drive technology. First user needs were identified by literature research and by patient feedback. Consequently, concepts were evaluated against technical and usability requirements. A first evaluation prototype with one active DoF per finger was manufactured. In a second step a test setup with two active DoF per finger was designed. The prototype is connected to an Android based smartphone application. Two main grip patterns can be preselected in the software application and afterwards changed and used by the EMG signal. Three different control algorithms can be selected: “all-day”, “fine” and “tired muscle”. Further parameters can be adjusted to customize the prosthesis to the patients’ needs. First patient feedback certified the prosthesis an improved level of handling compared to the existing devices. Using the two DoF test setup, the possibilities of finger control with a neural network are evaluated at the moment. In a first user feedback test, the smartphone based software application increased the device usability, e.g. the change within preselected grip patterns and the “tired muscle” algorithm. Although the overall software application was positively rated, the handling of the prosthesis itself needs to be proven within a patient study to be

Effect of silicone gel breast prosthesis on electron and photon dose distributions

International Nuclear Information System (INIS)

Krishnan, L.; St George, F.J.; Mansfield, C.M.; Krishnan, E.C.

1983-01-01

The effect of a silicone gel breast prosthesis on the absorbed dose distribution of 9-20 MeV electron beams and 1.25-15 MV photon beams was studied. Compared to water measurements, at depths smaller than the practical range of the electron beams, the central axis depth dose values below the prosthesis were lower for all energies by as much as 3.5%. However, at depths near the practical range, the central axis depth dose values for the prosthesis were greater than that of water by as much as 33%. Since this occurs near the end of the electron range, the resultant difference may not be clinically significant. Results of the effect of breast prosthesis on photon depth dose distributions reveal that no clinically significant perturbation is produced by the breast prosthesis using Co-60, 6- and 15-MV radiations

Fabrication of custom made ocular prosthesis with three different ...

African Journals Online (AJOL)

Loss of eye has a bad effect on the psychology of the patient. Eye prosthesis is fabricated to regain the patient's confidence by meticulous replacement of the missing eye. Immediate fitting of an anophthalmic socket with an artificial eye may not always be possible, and a delayed prosthesis delivery may result in settling and ...

Simplified technique for orbital prosthesis fabrication: a clinical report.

Science.gov (United States)

Veerareddy, Chandrika; Nair, K Chandrasekharan; Reddy, G Ramaswamy

2012-10-01

Loss of orbital content can cause functional impairment, disfigurement of the face, and psychological distress. Rehabilitation of an orbital defect is a complex task, and if reconstruction by plastic surgery is not possible or not desired by the patient, the defect can be rehabilitated by an orbital prosthesis. The prosthetic rehabilitation in such cases depends on the precisely retained, user-friendly removable maxillofacial prosthesis. Many times, making an impression of the orbital area with an accurate record of surface details can be a difficult procedure. The critical areas are making a facial moulage, mold preparation, and attaching the retention device, particularly when eyeglass frames are used. This case focuses on these hindrance factors. A simple basket was used for the impression tray to obtain the facial moulage. A putty mold was used, and attachment of the prosthesis to a retention device was accomplished with positional distance. This method proves to be an economical and simple way of making an orbital prosthesis. © 2012 by the American College of Prosthodontists.

[Rehabilitation by hollow obturator prosthesis immediately after total maxillectomy for malignant tumor].

Science.gov (United States)

Li, Xiao-ye; Yan, Ai-hui; Hao, Shuai; Li, Wei; Jiang, Xue-jun; Lu, Li; Qin, Xing-jun; Yan, Hai-xin

2011-05-01

The feasibility and clinical effects of hollow obturator prosthesis for the repair of maxillofacial defect immediately after maxillectomy for cancer were assessed. Thirteen patients with T3-4aN0M0 maxillary neoplasm were treated by the prostheses immediately after maxillectomy. According to the 3D-CT reconstruction of nasal sinus, the 3D stereoscopic prototype was constructed before the surgery. Simulating surgery with Surgicare 5.0 software and then the prosthesis 3D stereoscopic model was shaped. The prosthesis was made quickly and precisely with methacrylate resins according to the model and the print mold before surgery, with supplementary tooth at the bottom of prosthesis. In the surgery, the prosthesis was installed instantly after maxillectomy. The patients were followed up at 1, 3 and 6 month after the surgery, respectively. The facial features and the pronunciation clarity were examined and the questionnaires were carried out in the patients, with comparation by paired t-test. The hollow obturator prosthesis would be replaced by permanent prosthesis made of methacrylate resins at 6 month after the surgery. The hollow obturator prostheses were installed accurately and maxillofacial defects were repaired immediately after maxillectomy in the 13 patients. Postoperative follow-up showed there were significant differences in eyeball sagging (t = 4.67, P maxillectomy can improve survival quality of patient.

Treatment of femoral neck fracture by Moore Prosthesis in Cotonou ...

African Journals Online (AJOL)

Treatment of femoral neck fracture by Moore Prosthesis in Cotonou. AHM Akue, M Lawson, S Madougou, R Zannou, J Padonou. Abstract. Keywords: Benin; hip; Moore prosthesis; results. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Analysis of the mechanical behavior of the Nijdam voice prosthesis

NARCIS (Netherlands)

Verkerke, GJ; deVries, MP; Schutte, HK; vandenHoogen, FJA; Rakhorst, G

1997-01-01

The valveless Nijdam prosthesis is a new voice prosthesis for laryngectomized patients using tracheoesophageal speech. An ''umbrella-like hat'' covers the esophageal side of the tracheoesophageal fistula and is deformed during speech by air pressure. To decrease pressure loss during speech, a good

Custom-made silicone hand prosthesis: A case study.

Science.gov (United States)

Nayak, S; Lenka, P K; Equebal, A; Biswas, A

2016-09-01

Up to now, a cosmetic glove was the most common method for managing transmetacarpal (TMC) and carpometacarpal (CMC) amputations, but it is devoid of markings and body color. At this amputation level, it is very difficult to fit a functional prosthesis because of the short available length, unsightly shape, grafted skin, contracture and lack of functional prosthetic options. A 30-year-old male came to our clinic with amputation at the 1st to 4th carpometacarpal level and a 5th metacarpal that was projected laterally and fused with the carpal bone. The stump had grafted skin, redness, and an unhealed suture line. He complained of pain projected over the metacarpal and suture area. The clinical team members decided to fabricate a custom-made silicone hand prosthesis to accommodate the stump, protect the grafted skin, improve the hand's appearance and provide some passive function. The custom silicone hand prosthesis was fabricated with modified flexible wires to provide passive interphalangeal movement. Basic training, care and maintenance instructions for the prosthesis were given to the patient. The silicone hand prosthesis was able to restore the appearance of the lost digits and provide some passive function. His pain (VAS score) was reduced. Improvement in activities of daily living was found in the DASH questionnaire and Jebsen-Taylor Hand Function test. A silicone glove is a good option for more distal amputations, as it can accommodate any deformity, protect the skin, enhance the appearance and provide functional assistance. This case study provides a simple method to get passively movable fingers after proximal hand amputation. Copyright © 2016. Published by Elsevier Masson SAS.

Mastication improvement after partial implant-supported prosthesis use.

Science.gov (United States)

Gonçalves, T M S V; Campos, C H; Gonçalves, G M; de Moraes, M; Rodrigues Garcia, R C M

2013-12-01

Partially edentulous patients may be rehabilitated by the placement of removable dental prostheses, implant-supported removable dental prostheses, or partial implant fixed dental prostheses. However, it is unclear the impact of each prosthesis type over the masticatory aspects, which represents the objective of this paired clinical trial. Twelve patients sequentially received and used each of these 3 prosthesis types for 2 months, after which maximum bite force was assessed by a strain sensor and food comminution index was determined with the sieving method. Masseter and temporal muscle thicknesses during rest and maximal clenching were also evaluated by ultrasonography. Each maxillary arch received a new complete denture that was used throughout the study. Data were analyzed by analysis of variance for repeated measures, followed by the Tukey test (p mastication, and the magnitude of this effect was related to prosthesis type.

Structural valve deterioration in the Mitroflow biological heart valve prosthesis

DEFF Research Database (Denmark)

Issa, Issa Farah; Poulsen, Steen Hvitfeldt; Waziri, Farhad

2018-01-01

OBJECTIVES: Concern has been raised regarding the long-term durability of the Mitroflow biological heart valve prosthesis. Our aim was to assess the incidence of structural valve degeneration (SVD) for the Mitroflow bioprosthesis in a nationwide study in Denmark including all patients alive......: A total of 173 patients were diagnosed with SVD by echocardiography. Of these, 64 (11%) patients had severe SVD and 109 (19%) patients moderate SVD. Severe SVD was associated with the age of the prosthesis and small prosthesis size [Size 21: hazard ratio (95% confidence interval, CI) 2.72 (0.97-8.56), P...

Outcome of total knee arthroplasty with insall burstein-11 prosthesis

International Nuclear Information System (INIS)

Siddiq, M.Z.; Qayum, H.

2006-01-01

Patients with severe degenerative knee joint disease often require knee arthroplasty to reduce pain, improve stability and restore function. Insall Burstein II prosthesis is posteriorly stabilized condylar prosthesis, which provide posterior cruciate ligament substitution. It was designed to improve range of motion, stair climbing ability and to prevent posterior subluxation. Evaluate the functional outcome of total knee arthroplasty with IB II prosthesis and Evaluate the alignment of prosthetic components by radiological parameters and its correlation with functional outcome. Sixty knees of sixty patients were replaced by using Insall Burstein II prosthesis. Postoperative radiographs were evaluated for alignment of knee and prosthetic components by criteria selected from knee society roentogenographic evaluation system. Functional outcome was evaluated by rationale of knee society knee rating system. Prosthetic component was aligned in 93% and mal-alignment in 7% of the cases. There was significant improvement in functions core from mean score 33.83 +-15.5 to 59.5+-17.7 and knee score from 37 +- 12.5 to 76.4 +-2.2. Postoperative functional score was found correlated with alignment significantly. Conclusion: Total knee arthroplasty with I-B-II prosthesis is a safe durable and predictable procedure with proper surgical technique and expertise good alignment and satisfactory functional out come can be achieved. (author)

Prosthetic management of mid-facial defect with magnet-retained silicone prosthesis

OpenAIRE

Buzayan, M. M.

2014-01-01

Background and aim: Mid-facial defect is one of the most disfiguring and impairing defects. A design of prosthesis that is aesthetic and stable can be precious to a patient who has lost part of his face due to surgical excision. Prosthesis can restore the patients' self-esteem and confidence, which affects the patients and their life style. The aim of this case report is to describe a technique of mid-facial silicone prosthesis fabrication. Technique: To provide an aesthetic and stable facial...

Neurostimulation for bladder evacuation: is sacral root stimulation a substitute for microstimulation?

Science.gov (United States)

Probst, M; Piechota, H J; Hohenfellner, M; Gleason, C A; Tanagho, E A

1997-04-01

To determine by anatomical and functional studies whether stimulation of sacral rootlets might permit selective stimulation of autonomic fibres, thus avoiding the detrusor/sphincter dyssynergia characteristic of current techniques of neurostimulation for bladder evacuation. In 10 male mongrel dogs, the S2 root was isolated and its constituent rootlets followed from their origin in the spinal cord to the point of exit from the dura. The entire root and the individual rootlets were then stimulated, including intra- and extra-dural stimulation and at proximal, mid and distal levels. Neuroanatomical and histological findings showed that rootlets of ventral S2 maintain their identity throughout their intradural course; some carry predominantly autonomic fibres, some predominantly somatic and some a mixture of the two. It appears surgically feasible to identify, isolate and sever the predominantly somatic rootlets intradurally, sparing the predominantly autonomic rootlets for inclusion in extradural electrode placement around the entire sacral root, thus eliminating sphincteric interference with detrusor contraction for voiding at low pressure.

Acetabular prosthesis: Proff of migration with ruler and pencil?

International Nuclear Information System (INIS)

Diederichs, C.G.; Fischer, U.; Vosshenrich, R.

1993-01-01

Conventional X-ray films were made with varying degrees of tilt of a pelvic phantom containing an acetabular prosthesis. The position of the prosthesis was then reconstructed graphically. The measurement errors were calculated and an estimate was made for the tilt. There is a linear correlation between the measurement error and the tilt of the prosthesis. Therefore a tilt dependent maximum error can be calculated. This error is very small for small degrees of tilt, so that acetabular migration can in this instance be evaluated with greater confidence than with other graphical methods. The error also correlates with the determination of the selected region of the acetabulum, but not with the position of the central focus spot or image magnification. (orig.) [de

[Imaging evaluation on adaptability of proximal humeral anatomy after shoulder replacement with individualized shoulder prosthesis].

Science.gov (United States)

Shi, Youxing; Tang, Kanglai; Yuan, Chengsong; Tao, Xu; Wang, Huaqing; Chen, Bo; Guo, Yupeng

2015-03-24

Modern shoulder prosthesis has evolved through four generations. And the fourth generation technology has a core three-dimensional design of restoring 3D reconstruction of proximal humeral anatomy. Thus a new shoulder prosthesis is developed on the basis of the technology of 3D prosthesis. Assessment of whether shoulder prosthesis can restore individualized reconstruction of proximal humeral anatomy is based on the adaptability of proximal humeral anatomy. To evaluate the adaptability of proximal humeral anatomy through measuring the parameters of proximal humeral anatomy after shoulder replacement with individualized shoulder prosthesis and compare with normal data. The parameters of proximal humeral anatomy were analyzed and evaluated for a total of 12 cases undergoing shoulder replacement with individualized shoulder prosthesis. The relevant anatomical parameters included neck-shaft angle (NSA), retroversion angle (RA), humeral head height (HH) and humeral head diameter (HD). And the anatomical parameters were compared with the data from normal side. All underwent shoulder replacement with individualized shoulder prosthesis. The postoperative parameters of proximal humeral anatomy were compared with those of normal side. And the difference of NSA was 0.05). Individualized shoulder prosthesis has excellent adaptability to shoulder. All core parameters are freely adjustable and specification models may be optimized. With matching tools, individualized shoulder prosthesis improves the accuracy and reliability in shoulder replacement.

Rehabilitation of orbital cavity after orbital exenteration using polymethyl methacrylate orbital prosthesis

Directory of Open Access Journals (Sweden)

Sumeet Jain

2016-01-01

Full Text Available Squamous cell carcinoma of the eyelid is the second most common malignant neoplasm of the eye with the incidence of 0.09 and 2.42 cases/100 000 people. Orbital invasion is a rare complication but, if recognized early, can be treated effectively with exenteration. Although with advancements in technology such as computer-aided design and computer-aided manufacturing, material science, and retentive methods like implants, orbital prosthesis with stock ocular prosthesis made of methyl methacrylate retained by anatomic undercuts is quiet effective and should not be overlooked and forgotten. This clinical report describes prosthetic rehabilitation of two male patients with polymethyl methacrylate resin orbital prosthesis after orbital exenteration, for squamous cell carcinoma of the upper eyelid. The orbital prosthesis was sufficiently retained by hard and soft tissue undercuts without any complications. The patients using the prosthesis are quite satisfied with the cosmetic results and felt comfortable attending the social events.

Visual Prosthesis: Interfacing Stimulating Electrodes with Retinal Neurons to Restore Vision

Directory of Open Access Journals (Sweden)

Alejandro Barriga-Rivera

2017-11-01

Full Text Available The bypassing of degenerated photoreceptors using retinal neurostimulators is helping the blind to recover functional vision. Researchers are investigating new ways to improve visual percepts elicited by these means as the vision produced by these early devices remain rudimentary. However, several factors are hampering the progression of bionic technologies: the charge injection limits of metallic electrodes, the mechanical mismatch between excitable tissue and the stimulating elements, neural and electric crosstalk, the physical size of the implanted devices, and the inability to selectively activate different types of retinal neurons. Electrochemical and mechanical limitations are being addressed by the application of electromaterials such as conducting polymers, carbon nanotubes and nanocrystalline diamonds, among other biomaterials, to electrical neuromodulation. In addition, the use of synthetic hydrogels and cell-laden biomaterials is promising better interfaces, as it opens a door to establishing synaptic connections between the electrode material and the excitable cells. Finally, new electrostimulation approaches relying on the use of high-frequency stimulation and field overlapping techniques are being developed to better replicate the neural code of the retina. All these elements combined will bring bionic vision beyond its present state and into the realm of a viable, mainstream therapy for vision loss.

Multidisciplinary approach for in-deep assessment of joint prosthesis failure.

Science.gov (United States)

Tessarolo, F; Caola, I; Piccoli, F; Dorigotti, P; Demattè, E; Molinari, M; Malavolta, M; Barbareschi, M; Caciagli, P; Nollo, G

2009-01-01

In spite of advancement in biomaterials and biomechanics, in development of new osteo-integrative materials and coatings, and in macro- micro- component design, a non negligible fraction of the implanted prosthesis fails before the expected lifetime. A prospective observational clinical study has been conducted to define and apply a set of experimental techniques to in-deep assess the failure of joint prosthesis. Microbiological, histological and micro-structural techniques were implemented to specifically address phenomena occurring at the tissue-implant interface. Results obtained from 27 cases of prosthetic joint failure are discussed in terms of sensitivity and specificity. A procedural flow-chart is finally proposed for the assessment of joint prosthesis failure.

Electroencephalogram-Based Brain–Computer Interface and Lower-Limb Prosthesis Control: A Case Study

Directory of Open Access Journals (Sweden)

Douglas P. Murphy

2017-12-01

Full Text Available ObjectiveThe purpose of this study was to establish the feasibility of manipulating a prosthetic knee directly by using a brain–computer interface (BCI system in a transfemoral amputee. Although the other forms of control could be more reliable and quick (e.g., electromyography control, the electroencephalography (EEG-based BCI may provide amputees an alternative way to control a prosthesis directly from brain.MethodsA transfemoral amputee subject was trained to activate a knee-unlocking switch through motor imagery of the movement of his lower extremity. Surface scalp electrodes transmitted brain wave data to a software program that was keyed to activate the switch when the event-related desynchronization in EEG reached a certain threshold. After achieving more than 90% reliability for switch activation by EEG rhythm-feedback training, the subject then progressed to activating the knee-unlocking switch on a prosthesis that turned on a motor and unlocked a prosthetic knee. The project took place in the prosthetic department of a Veterans Administration medical center. The subject walked back and forth in the parallel bars and unlocked the knee for swing phase and for sitting down. The success of knee unlocking through this system was measured. Additionally, the subject filled out a questionnaire on his experiences.ResultsThe success of unlocking the prosthetic knee mechanism ranged from 50 to 100% in eight test segments.ConclusionThe performance of the subject supports the feasibility for BCI control of a lower extremity prosthesis using surface scalp EEG electrodes. Investigating direct brain control in different types of patients is important to promote real-world BCI applications.

Total Ossicular Replacement Prosthesis: A New Fat Interposition Technique

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Issam Saliba

2018-01-01

Full Text Available Objective: To compare audiometric results between the standard total ossicular replacement prosthesis (TORP-S and a new fat interposition total ossicular replacement prosthesis (TORP-F in pediatric and adult patients and to assess the complication and the undesirable outcome. Study design: This is a retrospective study. Methods: This study included 104 patients who had undergone titanium implants with TORP-F and 54 patients who had undergone the procedure with TORP-S between 2008 and 2013 in our tertiary care centers. The new technique consists of interposing a fat graft between the 4 legs of the universal titanium prosthesis (Medtronic Xomed Inc, Jacksonville, FL, USA to provide a more stable TORP in the ovale window niche. Normally, this prosthesis is designed to fit on the stapes’ head as a partial ossicular replacement prosthesis. Results: The postoperative air-bone gap less than 25 dB for the combined cohort was 69.2% and 41.7% for the TORP-F and the TORP-S groups, respectively. The mean follow-up was 17 months postoperatively. By stratifying data, the pediatric cohort shows 56.5% in the TORP-F group (n = 52 compared with 40% in the TORP-S group (n = 29. However, the adult cohort shows 79.3% in the TORP-F group (n = 52 compared with 43.75% in the TORP-S group (n = 25. These improvements in hearing were statistically significant. There were no statistically significant differences in the speech discrimination scores. The only undesirable outcome that was statistically different between the 2 groups was the prosthesis displacement: 7% in the TORP-F group compared with 19% in the TORP-S group ( P  = .03. Conclusions: The interposition of a fat graft between the legs of the titanium implants (TORP-F provides superior hearing results compared with a standard procedure (TORP-S in pediatric and adult populations because of its better stability in the oval window niche.

Total Ossicular Replacement Prosthesis: A New Fat Interposition Technique.

Science.gov (United States)

Saliba, Issam; Sabbah, Valérie; Poirier, Jackie Bibeau

2018-01-01

To compare audiometric results between the standard total ossicular replacement prosthesis (TORP-S) and a new fat interposition total ossicular replacement prosthesis (TORP-F) in pediatric and adult patients and to assess the complication and the undesirable outcome. This is a retrospective study. This study included 104 patients who had undergone titanium implants with TORP-F and 54 patients who had undergone the procedure with TORP-S between 2008 and 2013 in our tertiary care centers. The new technique consists of interposing a fat graft between the 4 legs of the universal titanium prosthesis (Medtronic Xomed Inc, Jacksonville, FL, USA) to provide a more stable TORP in the ovale window niche. Normally, this prosthesis is designed to fit on the stapes' head as a partial ossicular replacement prosthesis. The postoperative air-bone gap less than 25 dB for the combined cohort was 69.2% and 41.7% for the TORP-F and the TORP-S groups, respectively. The mean follow-up was 17 months postoperatively. By stratifying data, the pediatric cohort shows 56.5% in the TORP-F group (n = 52) compared with 40% in the TORP-S group (n = 29). However, the adult cohort shows 79.3% in the TORP-F group (n = 52) compared with 43.75% in the TORP-S group (n = 25). These improvements in hearing were statistically significant. There were no statistically significant differences in the speech discrimination scores. The only undesirable outcome that was statistically different between the 2 groups was the prosthesis displacement: 7% in the TORP-F group compared with 19% in the TORP-S group ( P  = .03). The interposition of a fat graft between the legs of the titanium implants (TORP-F) provides superior hearing results compared with a standard procedure (TORP-S) in pediatric and adult populations because of its better stability in the oval window niche.

Percutaneous Revision of a Testicular Prosthesis is Safe, Cost-effective, and Provides Good Patient Satisfaction

Directory of Open Access Journals (Sweden)

Eugene B. Cone

2015-09-01

Full Text Available Office-based percutaneous revision of a testicular prosthesis has never been reported. A patient received a testicular prosthesis but was dissatisfied with the firmness of the implant. In an office setting, the prosthesis was inflated with additional fluid via a percutaneous approach. Evaluated outcomes included patient satisfaction, prosthesis size, recovery time, and cost savings. The patient was satisfied, with no infection, leak, or complication after more than 1 year of follow-up, at significantly less cost than revision surgery. Percutaneous adjustment of testicular prosthesis fill-volume can be safe, inexpensive, and result in good patient satisfaction.

A direct bonded fixed partial dental prosthesis: A clinical report

OpenAIRE

Tanoue, Naomi; Tanaka, Takuo

2015-01-01

A direct bonded fixed partial dental prosthesis, with a composite resin denture tooth as a pontic, a tri-n-butylborane initiated adhesive resin, and screw posts for reinforcement, was still functioning after an observation period of 20 years. The prosthesis was found to be reliable for long-term clinical use when chemically and mechanically reinforced.

Rehabilitation of single finger amputation with customized silicone prosthesis

OpenAIRE

Yadav, Niharika; Chand, Pooran; Jurel, Sunit Kumar

2016-01-01

Finger amputations are common in accidents at home, work, and play. Apart from trauma, congenital disease and deformity also leads to finger amputation. This results in loss of function, loss of sensation as well as loss of body image. Finger prosthesis offers psychological support and social acceptance in such cases. This clinical report describes a method to fabricate ring retained silicone finger prosthesis in a patient with partial finger loss.

Dose distribution perturbation due to a Co-Cr-Mo prosthesis

International Nuclear Information System (INIS)

Castro Novais, J.; Rodriguez Rodriguez, C.; Cabello Murillo, E.; Fernandez Leton, P.; Perez Moreno, J. M.; Lopez Fernandez, A.; Ferrando Sanchez, A.; Martinez Gomez, L. C.

2009-01-01

Knowledge of the attenuation and interface effects when irradiating metallic prosthesis is necessary for the radiotherapy treatment of patients with this kind of implants. This report studies the dose distribution of a 6 MV photon beam in the vicinity of a 1,5 cm diameter Co-Cr-Mo prosthesis. Measurements with Gafchromic EBT radiochromic films have been made. Two blocks of cut films have been placed next to the prosthesis, one in each side. Forty two films reaching a height of 1 cm have been piled up in each block. A spatial resolution equal to the thickness of one film (0,24 mm) is achieved. The results show 28% attenuation and the production of a 42% overdose at the entrance interface, 12% and 3% at 1 mm and 2 mm away from the prosthesis respectively. A 5 mm build-up region is originated in the exit interface, where the under dose is less than 10%. The knowledge of the transmission factor and the interface effects allows us to assess the dose calculated by the treatment planning system. (Author) 11 refs.

Referral of sensation to an advanced humanoid robotic hand prosthesis.

Science.gov (United States)

Rosén, Birgitta; Ehrsson, H Henrik; Antfolk, Christian; Cipriani, Christian; Sebelius, Fredrik; Lundborg, Göran

2009-01-01

Hand prostheses that are currently available on the market are used by amputees to only a limited extent, partly because of lack of sensory feedback from the artificial hand. We report a pilot study that showed how amputees can experience a robot-like advanced hand prosthesis as part of their own body. We induced a perceptual illusion by which touch applied to the stump of the arm was experienced from the artificial hand. This illusion was elicited by applying synchronous tactile stimulation to the hidden amputation stump and the robotic hand prosthesis in full view. In five people who had had upper limb amputations this stimulation caused referral touch sensation from the stump to the artificial hand, and the prosthesis was experienced more like a real hand. We also showed that this illusion can work when the amputee controls the movements of the artificial hand by recordings of the arm muscle activity with electromyograms. These observations indicate that the previously described "rubber hand illusion" is also valid for an advanced hand prosthesis, even when it has a robotic-like appearance.

Adhesive strength of hydroxyl apatite(HA coating and biomechanics behavior of HA-coated prosthesis:an experimental study

Directory of Open Access Journals (Sweden)

Tian-yang ZHANG

2011-05-01

Full Text Available Objective To explore the influence of adhesive strength of hydroxyapatite(HA coating on the post-implantation stability of HA-coated prosthesis.Methods The adhesive strength and biomechanics behavior of HA coating were studied by histopathological observation,material parameters and biomechanical testing,the titanium(Ti-coated prosthesis was employed as control.Results Scratch test showed that the adhesive strength of HA coating was significantly lower than that of Ti coating(P < 0.01.Histopathological examination and bone morphometry showed that,at the early stage of prosthesis implantation,the bony growth around HA-coated prosthesis was significantly higher than that around Ti-coated prosthesis(P < 0.01,but the ultimate shear strength of HA-coated prosthesis was much lower than that of Ti-coated prosthesis(P < 0.01.After the push-out test with prosthesis,histopathological observation showed that there were accumulations of clump-and strip-like granular residues on the surface of bones that newly grew around the HA-coated prosthesis,and surface energy-dispersive X-ray spectroscopy(EDX analysis also confirmed that the shear stress induced HA decohesion from the substrate of prosthesis.Conclusions Although HA coating showed a satisfactory effect on early bone formation and prosthetic stability,due to the deficiencies of adhesive strength,the early stability of prosthesis may be gradually destroyed by the shear loads of human body and coating degradation.

Advanced engineering tools for design and fabrication of a custom nasal prosthesis

Science.gov (United States)

Oliveira, Inês; Leal, Nuno; Silva, Pedro; da Costa Ferreira, A.; Neto, Rui J.; Lino, F. Jorge; Reis, Ana

2012-09-01

Unexpected external defects resulting from neoplasms, burns, congenital malformations, trauma or other diseases, particularly when involving partial or total loss of an external organ, can be emotionally devastating. These defects can be restored with prosthesis, obtained by different techniques, materials and methods. The increase of patient numbers and cost constraints lead to the need of exploring new techniques that can increase efficiency. The main goal of this project was to develop a full engineering-based manufacturing process to obtain soft-tissue prosthesis that could provide faster and less expensive options in the manufacturing of customized prosthesis, and at the same time being able to reproduce the highest degree of details, with the maximum comfort for the patient. Design/methodology/approach - This case report describes treatment using silicone prosthesis with an anatomic retention for an 80-years-old woman with a rhinectomy. The proposed methodology integrates non-contact structured light scanning, CT and reverse engineering with CAD/CAM and additive manufacturing technology. Findings - The proposed protocol showed encouraging results since reveals being a better solution for fabricating custom-made facial prostheses for asymmetrical organs than conventional approaches. The process allows the attainment of prosthesis with the minimum contact and discomfort for the patient, disclosing excellent results in terms of aesthetic, prosthesis retention and in terms of time and resources consumed.

The method of manufacture of nylon dental partially removable prosthesis using additive technologies

Science.gov (United States)

Kashapov, R. N.; Korobkina, A. I.; Platonov, E. V.; Saleeva, G. T.

2014-12-01

The article is devoted to the topic of creating new methods of dental prosthesis. The aim of this work is to investigate the possibility of using additive technology to create nylon prosthesis. As a result of experimental studies, was made a sample of nylon partially removable prosthesis using 3D printing has allowed to simplify, accelerate and reduce the coat of manufacturing high-precision nylon dentures.

21 CFR 874.3540 - Prosthesis modification instrument for ossicular replacement surgery.

Science.gov (United States)

2010-04-01

... replacement surgery. 874.3540 Section 874.3540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... § 874.3540 Prosthesis modification instrument for ossicular replacement surgery. (a) Identification. A prosthesis modification instrument for ossicular replacement surgery is a device intended for use by a...

Predictors of Receiving a Prosthesis for Adults With Above-Knee Amputations in a Well-Defined Population.

Science.gov (United States)

Mundell, Benjamin F; Kremers, Hilal Maradit; Visscher, Sue; Hoppe, Kurtis M; Kaufman, Kenton R

2016-08-01

Prior studies have identified age as a factor in determining an individual's likelihood of receiving a prosthesis following a lower limb amputation. These studies are limited to specific subsets of the general population and are unable to account for preamputation characteristics within their study populations. Our study seeks to determine the effect of preamputation characteristics on the probability of receiving a prosthesis for the general population in the United States. To identify preamputation characteristics that predict of the likelihood of receiving a prosthesis following an above-knee amputation. A retrospective, population-based cohort study. Olmsted County, Minnesota (2010 population: 144,248). Individuals (n = 93) over the age of 18 years who underwent an above-knee amputation, that is, knee disarticulation or transfemoral amputation, while residing in Olmsted County, MN, between 1987 and 2013. Characteristics affecting the receipt of a prosthesis were analyzed using a logistic regression and a random forest algorithm for classification trees. Preamputation characteristics included age, gender, amputation etiology, year of amputation, mobility, cognitive ability, comorbidities, and time between surgery and the prosthesis decision. The association of preamputation characteristics with the receipt of a prosthesis following an above-knee amputation. Twenty-four of the participants received a prosthesis. The odds of receiving a prosthesis were almost 30 times higher in those able to walk independently prior to an amputation relative to those who could not walk independently. A 10-year increase in age was associated with a 53.8% decrease in the likelihood of being fit for a prosthesis (odds ratio = 0.462, P =.030). Time elapsed between surgery and the prosthesis decision was associated with a rise in probability of receiving a prosthesis for the first 3 months in the random forest algorithm. No other observed characteristics were associated with receipt

Achievable peak electrode voltage reduction by neurostimulators using descending staircase currents to deliver charge.

Science.gov (United States)

Halpern, Mark

2011-01-01

This paper considers the achievable reduction in peak voltage across two driving terminals of an RC circuit when delivering charge using a stepped current waveform, comprising a chosen number of steps of equal duration, compared with using a constant current over the total duration. This work has application to the design of neurostimulators giving reduced peak electrode voltage when delivering a given electric charge over a given time duration. Exact solutions for the greatest possible peak voltage reduction using two and three steps are given. Furthermore, it is shown that the achievable peak voltage reduction, for any given number of steps is identical for simple series RC circuits and parallel RC circuits, for appropriate different values of RC. It is conjectured that the maximum peak voltage reduction cannot be improved using a more complicated RC circuit.

Strategy to avoid patient-prosthesis mismatch: aortic root enlargement.

Science.gov (United States)

Srivastava, Dharmendra Kumar; Sanki, Prokash; Bhattacharya, Subhankar; Siddique, Javed Veqar

2014-02-01

The choice of a valve with an effective orifice area matching the body surface area and providing efficient hemodynamics is an important factor affecting mortality and morbidity in patients undergoing aortic valve replacement. Our preventative strategy was to implant a larger prosthetic valve by aortic root enlargement using the Nunez procedure in 17 patients between February 2010 and January 2011. The decision to enlarge the aortic root was taken when the 19-mm sizer could not be negotiated easily through the aortic root, or on the basis of body surface area of the patient or type of prosthesis available. Postoperative reductions in peak and mean pressure gradients across aortic valve of 12.8-16.5 and 10.2-12.6 mm Hg, respectively, were observed. Postoperative effective orifice areas of the aortic valves were 1.1-1.5 cm(2). By upsizing the aortic valve, we were able to eliminate patient-prosthesis mismatch in 5 patients, and reduce severe patient-prosthesis mismatch to moderate in 11. Aortic root enlargement is a safe procedure. Therefore, cardiac surgeons should not be reluctant to enlarge the aortic root with an autologous pericardial patch to permit implantation of an adequate size of aortic valve prosthesis, with minimal additional aortic crossclamp time and no added cost.

Smart image processing system for retinal prosthesis.

Science.gov (United States)

Weiland, James D; Parikh, Neha; Pradeep, Vivek; Medioni, Gerard

2012-01-01

Retinal prostheses for the blind have demonstrated the ability to provide the sensation of light in otherwise blind individuals. However, visual task performance in these patients remains poor relative to someone with normal vision. Computer vision algorithms for navigation and object detection were evaluated for their ability to improve task performance. Blind subjects navigating a mobility course had fewer collisions when using a wearable camera system that guided them on a safe path. Subjects using a retinal prosthesis simulator could locate objects more quickly when an object detection algorithm assisted them. Computer vision algorithms can assist retinal prosthesis patients and low-vision patients in general.

[Lessons from a heart valve prosthesis controversy].

Science.gov (United States)

Vandenbroucke, J P; Grobbee, D E

1998-07-18

Two lessons are to be learnt from the Björk-Shiley heart valve prosthesis tragedy. In the first place pharmacoepidemiologic studies are seriously hampered by recent privacy legislation. Individual patients carrying such a prosthesis cannot be traced and advised as to their health risks any more, because their legal autonomy has to be respected. This is clearly not to their advantage. In the second place the atmosphere of marketing and litigation and the increasing dependency of researchers on money from sources with conflicting interests is not conducive to a well-informed and balanced judgement of the epidemiological evidence of safety and efficacy of medical treatments.

Combined nuclear and digital subtraction contrast arthrography in painful knee prosthesis

International Nuclear Information System (INIS)

Namasivayam, J.; Forrester, A.; Poon, F.W.; Cuthbert, G.F.; McKillop, J.H.; Bryan, A.S.

1992-01-01

The evaluation of a painful knee prosthesis remains a difficult problem for both orthopaedic surgeons and radiologists. We have compared digital subtraction arthrography with nuclear-arthrography in 7 patients with a painful knee prosthesis. Three patients showed a loose tibial component, demonstrated by both digital subtraction and nuclear arthrography. All 3 underwent revision of their prosthesis. One patient had an equivocal digital subtraction arthrogram and negative nuclear arthrogram, while both studies were negative in the 3 remaining patients. Nuclear arthrography is a simple procedure and can provide useful additional information when combined with digital subtraction arthrography. (orig.)

21 CFR 878.3720 - Tracheal prosthesis.

Science.gov (United States)

2010-04-01

...) Identification. The tracheal prosthesis is a rigid, flexible, or expandable tubular device made of a silicone... of the trachea or trachealbronchial tree. It may be unbranched or contain one or two branches. The...

Magnetically retained silicone facial prosthesis

African Journals Online (AJOL)

2013-06-09

Jun 9, 2013 ... Prosthetic camouflaging of facial defects and use of silicone maxillofacial material are the alternatives to the surgical retreatment. Silicone elastomers provide more options to clinician for customization of the facial prosthesis which is simple, esthetically good when coupled with bio magnets for retention.

Pattern of External Breast Prosthesis Use by Post Mastectomy Breast Cancer Patients in India: Descriptive Study from Tertiary Care Centre.

Science.gov (United States)

Ramu, D; Ramesh, Rakesh S; Manjunath, Suraj; Shivakumar; Goel, Vipin; Hemnath, G N; Alexander, Annie

2015-12-01

In India, Breast cancer is now the most common cancer in urban and 2nd most common in rural areas [1]. The incidence is rising, more younger women are getting affected and due to increase in survival rates there is an increase in the total number of women suffering from breast Cancer. So far there are no studies evaluating the pattern of breast prosthesis use in Indian scenario. The aim of this study is to address the patterns of external breast prosthesis used in India and view of Indian women on such prosthesis after mastectomy for breast cancer. This was a descriptive longitudinal study. In this study we interviewed (telephonic) 63 people, after three years of completing treatment under The Department of Surgical Oncology, St. Johns medical college, Bangalore. Among the study group, 27 members (40 %) were using various prosthesis, rest 36 women were not using any type of prosthesis. Among the users of prosthesis, silicon prosthesis was used by 6 women, padded cups by 8 women, cloth or cotton by 12 women and 1 woman used other type of prosthesis. Most women use simple items like cloth and cotton (44 %). Next most commonly used prosthesis are padded cups(). Only 22 % of women were found using silicon prosthesis in this study. Most of the well educated patients used external prosthesis either in the form of silicon prosthesis or padded cups. Most of women below age of 50 used external breast prosthesis. Use of prosthesis was more in urban compared to rural population (48 % vs 25 %). Prosthesis users worried more about the body image than women not using prosthesis. 25 % of women using prosthesis had body image issues where as only 5 % of non prosthesis users had such problems. Prosthesis users need improvement in terms of comfort, size, shape and affordability. Most common reasons for not using prosthesis are age, lack of motivation and awareness. Less than half of the women included in this study used external prosthesis after mastectomy for breast cancer

Candida albicans, Staphylococcus aureus and Streptococcus mutans colonization in patients wearing dental prosthesis.

Science.gov (United States)

Baena-Monroy, Tania; Moreno-Maldonado, Víctor; Franco-Martínez, Fernando; Aldape-Barrios, Beatriz; Quindós, Guillermo; Sánchez-Vargas, Luis Octavio

2005-04-01

Denture stomatitis is associated to Candida albicans, different bacteria and other co-factors such as an acid pH, a carbohydrate ingestion increase, different systemic illnesses and pharmacological treatments. The aim of this study was to determine Candida albicans, Staphylococcus aureus and Streptococcus mutans prevalence in the mucous membrane and prosthesis of patients with and without atrophic denture stomatitis and its relationship with other potential clinical co-factors. Saliva was collected from 105 patients (62 female and 43 male) wearing dental prosthesis in order to measure their pH. Oral samples of the mucous membrane and the internal surface of dental prosthesis were taken with sterile cotton to proceed with the microbiological study. The identification of the isolated microorganisms was performed using conventional microbiological methods. Diabetes and Hypertension were the most frequent systemic illnesses. High carbohydrate ingestion was observed in numerous patients. Atrophic denture stomatitis was reported in 50 patients and the pH average in saliva was of 5.2. The presence of C albicans, S. aureus and S. mutans in the mucous membrane and prosthesis was of 51.4%, 52.4% and 67.6%, respectively. C. albicans was isolated in 66.7% from the prosthesis, whereas S. aureus and S. mutans were isolated in 49.5% of those same prosthesis. C. albicans was isolated in 86% of the patients with atrophic denture stomatitis and S. aureus was isolated in a similar percentage (84% of patients). The isolation of S. mutans was less frequent, and it was observed in 16% of the oral samples of these patients. C. albicans, S. aureus and S. mutans frequently colonize the oral mucous of patients wearing dental prosthesis. This illness-bearing condition is more frequent in patients with denture stomatitis, even though dental prosthesis colonization is lower than in the oral mucous.

Survival of various implant-supported prosthesis designs following 36 months of clinical function.

Science.gov (United States)

Rodriguez, A M; Orenstein, I H; Morris, H F; Ochi, S

2000-12-01

The use of endosseous dental implants to replace natural teeth lost to trauma, dental caries, or periodontal disease has become a predictable form of prosthetic treatment since gaining popularity in the early 1980s. While numerous clinical studies have focused on the survival of implants, few address the survival of different prosthesis designs. Beginning in 1991, 882 prostheses supported by more than 2,900 implants (687 patients) were placed by the Department of Veterans Affairs Dental Implant Clinical Research Group (DICRG). These prostheses were divided into five research strata based on arch location. The recommended design for each stratum was: bar-supported overdenture (maxillary completely edentulous); screw-retained hybrid denture (mandibular completely edentulous); screw-retained fixed partial denture (mandibular and maxillary posterior partially edentulous); and cemented single crown (maxillary anterior single tooth). Alternative overdenture designs were utilized in the edentulous arches when the recommended prosthesis could not be fabricated. Prosthesis success rates for the research strata were calculated for an observation time of up to 36 months following prosthesis placement. Success rates for the maxillary edentulous stratum ranged from 94.6% for the bar-retained overdenture supported by five to six fixtures to 81.8% for the cap-retained overdenture. The mandibular edentulous strata produced success rates of 98.1% for the fixed hybrid prosthesis to 91.7% for the cap-retained prosthesis. Success rates for maxillary and mandibular posterior fixed partial dentures were 94.3% and 92.6%, respectively, while the maxillary anterior single-tooth prosthesis yielded a success rate of 98.1% for the 36-month observation period. The recommended prosthesis designs investigated in this study proved to be reliable, with encouraging success rates for an observation period of 36 months following placement.

Retrospective Study on External Canine Limb Prosthesis used in 24 patients

Directory of Open Access Journals (Sweden)

Brittany Jean Carr

2018-03-01

Full Text Available Objective: The purpose of this retrospective study is to provide data regarding external prosthetic use in small animal patients, evaluate the common complications associated with external prosthetics, and evaluate the outcome of patients using an external prosthetic.Background: The use of external canine limb prosthetics is relatively uncommon in veterinary medicine today.  However, there is growing interest in prosthetics and their clinical application because these devices may offer an alternative to euthanasia in severe cases where full amputation or alternative methods of limb spare are not an option. The goal of the prosthesis is to provide a better quality of life, help prevent further deformation and degeneration of existing joints, decrease leg length discrepancies, increase exercise and activity levels, provide a means to participate in rehabilitation therapy and maintain the ability to perform daily acts of living. To the author’s knowledge, there is no report of external prosthetic use in small animal veterinary medicine, providing the profession with baseline information for use in, not only general practice or referral practice, but also future research.Evidentiary value: This retrospective study provides data regarding external prosthetic use in small animal patients, evaluates the procedures, manufacturing, rehabilitation and common complications associated with external prosthetics, and evaluates the factors that determine a patient’s prosthetic candidacy.Methods: Patients that had an external prosthesis custom manufactured for them at Animal Orthocare, LLC and had a complete medical record were identified for this study.  A client survey was completed via e-mail or telephone to collect further data about the patients, including age, weight, breed, sex, affected limb(s, reason for prosthesis, level of amputation, activities patient could perform with prosthesis in place, prosthetic fit, prosthetic migration (e

Research, design and development project Myoelectric Prosthesis of Upper Limb

International Nuclear Information System (INIS)

Galiano, L; Montaner, E; Flecha, A

2007-01-01

A Research Design and Development Project was developed of a myoelectric prosthesis for a pediatric patient presenting congenital amputation of the left forearm below the elbow. A multidisciplinary work-team was formed for this goal, in order to solve the several (/various) aspects regarding this project (mechanical, ergonomics, electronics, physical). The prosthesis as an electromechanical device was divided in several blocks, trying to achieve a focused development for each stage, acording to requisites. A mechanical prototype of the prothesis was designed and built along with the circuitry needed for EMG aquisition, control logic and drivers. Having acomplished the previuos stages, the project is now dealing with the definitions of the interface between the prosthesis and the patient, with promising perspectives

Research, design and development project Myoelectric Prosthesis of Upper Limb

Energy Technology Data Exchange (ETDEWEB)

Galiano, L; Montaner, E; Flecha, A [Bioparx, J Hernandez 1101, Parana, ERios (Argentina)

2007-11-15

A Research Design and Development Project was developed of a myoelectric prosthesis for a pediatric patient presenting congenital amputation of the left forearm below the elbow. A multidisciplinary work-team was formed for this goal, in order to solve the several (/various) aspects regarding this project (mechanical, ergonomics, electronics, physical). The prosthesis as an electromechanical device was divided in several blocks, trying to achieve a focused development for each stage, acording to requisites. A mechanical prototype of the prothesis was designed and built along with the circuitry needed for EMG aquisition, control logic and drivers. Having acomplished the previuos stages, the project is now dealing with the definitions of the interface between the prosthesis and the patient, with promising perspectives.

21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis. 888.3170 Section 888.3170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer...

Prosthesis-patient mismatch due to small ring annuloplasty in patients with degenerative mitral insufficiency.

Science.gov (United States)

Kawamoto, Naonori; Fujita, Tomoyuki; Hata, Hiroki; Shimahara, Yusuke; Sato, Shunsuke; Kobayashi, Junjiro

2016-08-01

Avoidance of prosthesis-patient mismatch (PPM) is important when selecting a mitral valve prosthesis. This study investigated the effect of PPM after small ring mitral valve annuloplasty on postoperative hemodynamics and the clinical course. This study retrospectively reviewed 227 patients with symptomatic severe mitral insufficiency (MI) who underwent mitral valve repair for degenerative MI using an Edwards ring or band (size: 26-32mm) between 2003 and 2012. Echocardiography was performed postoperatively and at follow-up to evaluate cardiac function, including residual MI, mean transmitral pressure gradient, left atrial diameter (LAD), and tricuspid regurgitant pressure gradient (TRPG). There were no operative deaths. Actuarial freedom from major adverse cardiac events was 91% at 10 years. The postoperative MI grade was not significantly different between different sizes of prosthesis (26mm, 0.67±0.8; 28mm, 0.73±0.9; 30mm, 0.85±0.9; 32mm, 0.3±0.6). LAD and TRPG were significantly lower for each size of prosthesis at follow-up (all pbody surface area received a significantly smaller prosthesis (pprosthesis than in patients with a larger size of prosthesis. Thirty-three patients had a follow-up transmitral pressure gradient ≥5mmHg. The follow-up LAD was larger in patients with a transmitral pressure gradient prosthesis. However, use of a smaller prosthesis may result in a higher mean transmitral pressure gradient, and may inhibit reverse remodeling of the left atrium. Therefore, PPM should be avoided. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Can nanofluidic chemical release enable fast, high resolution neurotransmitter-based neurostimulation?

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Peter D Jones

2016-03-01

Full Text Available Artificial chemical stimulation could provide improvements over electrical neurostimulation. Physiological neurotransmission between neurons relies on the nanoscale release and propagation of specific chemical signals to spatially-localized receptors. Current knowledge of nanoscale fluid dynamics and nanofluidic technology allows us to envision artificial mechanisms to achieve fast, high resolution neurotransmitter release. Substantial technological development is required to reach this goal. Nanofluidic technology — rather than microfluidic — will be necessary; this should come as no surprise given the nanofluidic nature of neurotransmission.This perspective reviews the state of the art of high resolution electrical neuroprostheses and their anticipated limitations. Chemical release rates from nanopores are compared to rates achieved at synapses and with iontophoresis. A review of microfluidic technology justifies the analysis that microfluidic control of chemical release would be insufficient. Novel nanofluidic mechanisms are discussed, and we propose that hydrophobic gating may allow control of chemical release suitable for mimicking neurotransmission. The limited understanding of hydrophobic gating in artificial nanopores and the challenges of fabrication and large-scale integration of nanofluidic components are emphasized. Development of suitable nanofluidic technology will require dedicated, long-term efforts over many years.

Evaluation of possible hip prosthesis infection with In-111 leukocyte scintigraphy

International Nuclear Information System (INIS)

Noto, R.B.; Alavi, A.; Star, A.M.; Cuckler, J.M.; Eisenberg, B.

1987-01-01

To evaluate the utility of In-111 leukocyte scintigraphy in patients with possible hip prosthesis infection, the authors retrospectively reviewed 44 such scans without clinical history. The results of In-111 leukocyte scans were compared with intraoperative cultures obtained at the time of prosthesis revision in 34 patients, with hip aspirates and/or clinical follow-up obtained in the remaining ten patients. This comparison yielded a 71% sensitivity, 78% specificity, and 77% overall accuracy. They conclude that In-111 leukocyte scans can be helpful in the evaluation of suspected hip prosthesis infection, but they are not as accurate as has been previously reported elsewhere

A Structural Analysis of a Mechanical Heart Valve Prosthesis with Flat Leaflet

Science.gov (United States)

Kwon, Young Joo

This paper addresses the basic concept of MDO methodology and the structural analysis that should be performed in the design process of a mechanical heart valve prosthesis with flat leaflet using MDO methodology. In the structural design of the mechanical heart valve (MHV) prosthesis, the fluid mechanics analysis is executed for the blood flow passing through the leaflets of a mechanical heart valve prosthesis. Thereafter, the rigid body dynamics analysis of the leaflet motion is performed to obtain the structural condition for the structural mechanics analysis of the deformed leaflet. Then the structural mechanics analysis of the deformed leaflet follows to confirm the minimum thickness of the leaflet for the structural durability of the mechanical heart valve prosthesis. This paper shows that the minimum leaflet thickness can be evaluated to be 0.6mm among the suggested thicknesses.

Effect of silicone gel breast prosthesis on electron and photon dose distributions

International Nuclear Information System (INIS)

Krishnan, L.; St George, F.J.; Mansfield, C.M.; Krishnan, E.C.

1983-01-01

The effect of a silicone gel breast prosthesis on the absorbed dose distribution of 9--20 MeV electron beams and 1.25--15 MV photon beams was studied. Compared to water measurements, at depths smaller than the practical range of the electron beams, the central axis depth dose values below the prothesis were lower for all energies by as much as 3.5%. However, at depths near the practical range, the central axis depth dose values for the prosthesis were greater than that of water by as much as 33%. Since this occurs near the end of the electron range, the resultant difference may not be clinically significant. Results of the effect of breast prosthesis on photon depth dose distributions reveal that no clinically significant perturbation is produced by the breast prosthesis using Co-60, 6- and 15-MV radiations

Quantifying risk of penile prosthesis infection with elevated glycosylated hemoglobin.

Science.gov (United States)

Wilson, S K; Carson, C C; Cleves, M A; Delk, J R

1998-05-01

Elevation of glycosylated hemoglobin above levels of 11.5 mg.% has been considered a contraindication to penile prosthesis implantation in diabetic patients. We determine the predictive value of glycosylated hemoglobin A1C in penile prosthesis infections in diabetic and nondiabetic patients to confirm or deny this prevalent opinion. We conducted a 2-year prospective study of 389 patients, including 114 diabetics, who underwent 3-piece penile prosthesis implantation. All patients had similar preoperative preparation without regard to diabetic status, control or glycosylated hemoglobin A1C level. Risk of infection was statistically analyzed for diabetics versus nondiabetics, glycosylated hemoglobin A1C values above and below 11.5 mg.%, insulin dependent versus oral medication diabetics, and fasting blood sugars above and below 180 mg.%. Prosthesis infections developed in 10 diabetics (8.7%) and 11 nondiabetics (4.0%). No increased infection rate was observed in diabetics with high fasting sugars or diabetics on insulin. There was no statistically significant increased infection risk with increased levels of glycosylated hemoglobin A1C among all patients or among only the diabetics. In fact, there was no meaningful difference in the median or mean level of glycosylated hemoglobin A1C in the infected and noninfected patients regardless of diabetes. Use of glycosylated hemoglobin A1C values to identify and exclude surgical candidates with increased risk of infections is not proved by this study. Elevation of fasting sugar or insulin dependence also does not increase risk of infection in diabetics undergoing prosthesis implantation.

Wispy Prosthesis: A Novel Method in Denture Weight Reduction.

Science.gov (United States)

Anne, Gopinadh; Budeti, Sreedevi; Anche, Sampath Kumar; Zakkula, Srujana; Atla, Jyothi; Jyothula, Ravi Rakesh Dev; Appana, Krishna Chaitanya; Peddinti, Vijaya Kumar

2016-04-01

Stability and retention of the denture becomes at stake with the increase in weight of the denture prosthesis. As a consequence, different materials and methods have been introduced to overcome these issues but denture weight reduction still remains to be a cumbersome and strenuous procedure. To introduce a novel technique for the fabrication of denture prosthesis where in the weight of the denture will not affect the retention and stability of the denture. Four groups with a sample size of 10 each, were included where in one group was control and other three were study groups. The control group samples were made completely solid and the study group samples were packed with materials like bean balls, cellulose balls and polyacrylic fibers. The weight of all the samples of each study group was measured and compared with the control group. The observations were analyzed statistically by paired t-test. It was observed that the bean balls group produced a weight reduction of 31.3%, cellulose balls group 27.4% and polyacrylic fibers group 24.5% when compared to that of the control group. This novel technique will eliminate the problems that were associated in creating hollowness and at the same time will reduce the weight of the prosthesis and among all the study groups, bean balls group were found to reduce maximum weight of the prosthesis.

A fiber-reinforced composite prosthesis restoring a lateral midfacial defect: a clinical report.

Science.gov (United States)

Kurunmäki, Hemmo; Kantola, Rosita; Hatamleh, Muhanad M; Watts, David C; Vallittu, Pekka K

2008-11-01

This clinical report describes the use of a glass fiber-reinforced composite (FRC) substructure to reinforce the silicone elastomer of a large facial prosthesis. The FRC substructure was shaped into a framework and embedded into the silicone elastomer to form a reinforced facial prosthesis. The prosthesis is designed to overcome the disadvantages associated with traditionally fabricated prostheses; namely, delamination of the silicone of the acrylic base, poor marginal adaptation over time, and poor simulation of facial expressions.

Subway Mandibular Buccal Defect Blocked with Two Part Prosthesis Unified by Earth Magnets

OpenAIRE

Punjani, Shikha; Arora, Aman; Upadhyaya, Viram

2012-01-01

This clinical report describes the fabrication of a two-piece obturator used to close the mandibular buccal defect. Two-piece obturator prosthesis was fabricated with clear heat cure acrylic resin to be used during the healing period following the marsupialization of odontogenic keratocyst which had lead to the loss of portions of the mandibular buccal region. The prosthesis fabricated in two parts was joined by the rare earth magnets. Retention was increased by lining the prosthesis with tis...

Aspiration of tracheoesophageal prosthesis in a laryngectomized patient

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Conte Sergio C

2012-08-01

Full Text Available Abstract Background The voice prosthesis inserted into a tracheoesophageal fistula has become the most widely used device for voice rehabilitation in patients with total laryngectomy. Case presentation We describe a case of tracheoesophageal prosthesis’ (TEP aspiration in a laryngectomized patient, with permanent tracheal stoma, that appeared during standard cleaning procedure, despite a programme of training for the safe management of patients with voice prosthesis. Conclusions The definitive diagnosis and treatment were performed by flexible bronchoscopy, that may be considered the procedure of choice in these cases, also on the basis of the literature.

Tracheobronchial Foreign Body Aspiration: Dental Prosthesis

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Ataman Köse

2014-01-01

Full Text Available It is important to extract foreign bodies for avoiding life-threatening complications. They can lead to death if they are not treated. Different signs and symptoms could occur according to the complete or partial airway obstruction. Foreign body aspiration is a rare incident in adults. The organic foreign materials such as foods are found to be aspirated more commonly and are usually settled in the right bronchial system. However, dental prosthesis and teeth aspirations are rare in literature. In our study, a 52-year-old male patient who had aspirated the front part of his lower dental prosthesis accidentally is presented and the foreign body is extracted by using rigid bronchoscopy. There are many causes of aspiration but dental prosthetic aspirations should be kept in mind during sleep. For this reason, dental apparatus must be taken out while asleep.

Stress analysis of different prosthesis materials in implant-supported fixed dental prosthesis using 3D finite element method

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Pedram Iranmanesh

2014-01-01

Full Text Available Introduction: In the present study, the finite element method (FEM was used to investigate the effects of prosthesis material types on stress distribution of the bone surrounding implants and to evaluate stress distribution in three-unit implant-supported fixed dental prosthesis (FDP. Materials and Methods: A three-dimensional (3D finite element FDP model of the maxillary second premolar to the second molar was designed. Three load conditions were statically applied on the functional cusps in horizontal (57.0 N, vertical (200.0 N, and oblique (400.0 N, θ = 120° directions. Four standard framework materials were evaluated: Polymethyl methacrylate (PMMA, base-metal, porcelain fused to metal, andporcelain. Results: The maximum of von Mises stress in the oblique direction was higher than the vertical and horizontal directions in all conditions. In the bone-crestal section, the maximum von Mises stress (53.78 MPa was observed in PMMA within oblique load. In FDPs, the maximum stress was generated at the connector region in all conditions. Conclusion: A noticeable difference was not observed in the bone stress distribution pattern with different prosthetic materials. Although, higher stress value could be seen in polymethyl methacrylate, all types of prosthesis yielded the same stress distribution pattern in FDP. More clinical studies are needed to evaluate the survival rate of these materials.

Adjuvant Maneuvers for Residual Curvature Correction During Penile Prosthesis Implantation in Men with Peyronie's Disease.

Science.gov (United States)

Berookhim, Boback M; Karpman, Edward; Carrion, Rafael

2015-11-01

The surgical treatment of comorbid erectile dysfunction and Peyronie's disease has long included the implantation of an inflatable penile prosthesis as well as a number of adjuvant maneuvers to address residual curvature after prosthesis placement. To review the various surgical options for addressing curvature after prosthesis placement, with specific attention paid to an original article by Wilson et al. reporting on modeling over a penile prosthesis for the management of Peyronie's disease. A literature review was performed analyzing articles reporting the management of penile curvature in patients undergoing implantation of an inflatable penile prosthesis. Reported improvement in Peyronie's deformity as well as the complication rate associated with the various surgical techniques described. Modeling is a well-established treatment modality among patients with Peyronie's disease undergoing penile prosthesis implantation. A variety of other adjuvant maneuvers to address residual curvature when modeling alone is insufficient has been presented in the literature. Over 20 years of experience with modeling over a penile prosthesis have proven the efficacy and safety of this treatment option, providing the surgeon a simple initial step for the management of residual curvature after penile implantation which allows for the use of additional adjuvant maneuvers in those with significant deformities. © 2015 International Society for Sexual Medicine.

Insidious strut fractures in a DeBakey-Surgitool aortic valve prosthesis.

Science.gov (United States)

Scott, S M; Sethi, G K; Paulson, D M; Takaro, T

1978-04-01

Recent reports of cage wear occurring in DeBakey-Surgitool aortic valve prostheses prompted us to examine with image intensification all our patients who have had this type of prosthesis implanted. One patient, who was asymptomatic, was discovered to have a prosthesis with two fractured struts. This patient's prosthetic valve was replaced successfully with a stented porcine heterograft prosthesis. Including the valve removed from this patient, 8 DeBakey-Surgitool aortic valves with structural defects have been reported to the manufacturer. In the absence of a catastrophic event, patients with valves having fractured or worn struts may be totally asymptomatic, and routine periodic roentgenographic examination may be the only way of detecting strut wear or fracture.

A Biomechanical Model for the Development of Myoelectric Hand Prosthesis Control Systems

NARCIS (Netherlands)

Peerdeman, B.; van Baal, D.W.; Boere, Daphne; Kallenberg, L.A.C.; Stramigioli, Stefano; Misra, Sarthak

2010-01-01

Advanced myoelectric hand prostheses aim to reproduce as much of the human hand's functionality as possible. Development of the control system of such a prosthesis is strongly connected to its mechanical design; the control system requires accurate information on the prosthesis' structure and the

Surgical treatment for progressive prostate cancer: A clinical case

Directory of Open Access Journals (Sweden)

E. I. Veliev

2014-01-01

Full Text Available In spite of its existing standards, the treatment of patients with progressive prostate cancer (PC remains a matter of debate. Ensuring that the patients have good quality of life is also relevant. The paper describes a clinical case of a patient with progressive PC after hormone therapy, brachytherapy, salvage prostatectomy, enucleation of the testicular parenchyma, and salvage lymphadenectomy. A phallic prosthesis and an artificial urinary sphincter have been implanted to improve quality of life. The results of preoperative examination and the technological features of surgical interventions are given.

Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia

Directory of Open Access Journals (Sweden)

Amjad Alwaal

2017-01-01

Conclusions: There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

An “Uncrimped” SMart Stapes Prosthesis: A Cause of Late Hearing Deterioration in Otosclerosis

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Premjit S. Randhawa

2012-01-01

Full Text Available Statement of Problem. Stapedotomy is the treatment of choice for otosclerosis. Numerous techniques and prosthesis are available to perform this procedure. Success rates of surgery vary from 17% to 80%, and revision surgery carries an increased risk of complications as well as poorer hearing outcomes. Method of Study. Case report. Results. We report the first case of uncrimping of a SMart stapes prosthesis with no lateral displacement as a cause of late failure despite successful crimping and improvement in audiological outcomes after initial surgery. Conclusion. The SMart stapes prosthesis is widely used and has been shown to be safe and provide good hearing outcomes. Displacement of a stapes prosthesis is the commonest cause of failure. Our case shows that deterioration of hearing thresholds can occur from uncrimping of the prosthesis with no displacement. It is important to improve our understanding of stapedotomy failure as revision procedures are associated with poorer outcomes.

Prosthesis Prescription Protocol of the Arm (PPP-Arm) : The implementation of a national prosthesis prescription protocol

NARCIS (Netherlands)

Wijdenes, Paula; Brouwers, Michael; van der Sluis, Corry K

BACKGROUND AND AIM: In order to create more uniformity in the prescription of upper limb prostheses by Dutch rehabilitation teams, the development and implementation of a Prosthesis Prescription Protocol of the upper limb (PPP-Arm) was initiated. The aim was to create a national digital protocol to

PARTIAL REPLACEMENT OF THE ESOPHAGEAL MUSCLE LAYERS BY A CARBON-FIBER PROSTHESIS

NARCIS (Netherlands)

RUKA, MP; TUNGEKAR, MF; KUIT, J; HOFSTRA, W

1991-01-01

In the present study we report on the surgical replacement of the thoracic portion of oesophageal muscularis by a synthetic carbon fibre (CF) prosthesis in a rabbit model. Our results, as corroborated by the oesophagograms and the post-operative weight gain, showed that this prosthesis functioned

Restoration of an atrophic eye socket with custom made eye prosthesis, utilizing digital photography

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Gaurav P Jayaswal

2011-01-01

Full Text Available Ocular defects may cause several ocular and orbital disorders, which require surgical intervention. These defects are psychologically disturbing for the patients, and therefore, they require immediate management and rehabilitation by a team of specialist. Ocular prosthesis may be either readymade (stock or custom made. Fabrication of a custom ocular prosthesis allows for a range of variations during construction. The iris can also be custom made by ocular painting or by digital photography. The optimum cosmetic and functional results of a custom-made prosthesis enhance the patient′s rehabilitation to a normal life style. This paper elaborates the technique for fabrication of a custom-made ocular prosthesis for an atrophic eye socket utilizing digital photography.

Optimization of Visual Information Presentation for Visual Prosthesis

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Fei Guo

2018-01-01

Full Text Available Visual prosthesis applying electrical stimulation to restore visual function for the blind has promising prospects. However, due to the low resolution, limited visual field, and the low dynamic range of the visual perception, huge loss of information occurred when presenting daily scenes. The ability of object recognition in real-life scenarios is severely restricted for prosthetic users. To overcome the limitations, optimizing the visual information in the simulated prosthetic vision has been the focus of research. This paper proposes two image processing strategies based on a salient object detection technique. The two processing strategies enable the prosthetic implants to focus on the object of interest and suppress the background clutter. Psychophysical experiments show that techniques such as foreground zooming with background clutter removal and foreground edge detection with background reduction have positive impacts on the task of object recognition in simulated prosthetic vision. By using edge detection and zooming technique, the two processing strategies significantly improve the recognition accuracy of objects. We can conclude that the visual prosthesis using our proposed strategy can assist the blind to improve their ability to recognize objects. The results will provide effective solutions for the further development of visual prosthesis.

Optimization of Visual Information Presentation for Visual Prosthesis

Science.gov (United States)

Gao, Yong

2018-01-01

Visual prosthesis applying electrical stimulation to restore visual function for the blind has promising prospects. However, due to the low resolution, limited visual field, and the low dynamic range of the visual perception, huge loss of information occurred when presenting daily scenes. The ability of object recognition in real-life scenarios is severely restricted for prosthetic users. To overcome the limitations, optimizing the visual information in the simulated prosthetic vision has been the focus of research. This paper proposes two image processing strategies based on a salient object detection technique. The two processing strategies enable the prosthetic implants to focus on the object of interest and suppress the background clutter. Psychophysical experiments show that techniques such as foreground zooming with background clutter removal and foreground edge detection with background reduction have positive impacts on the task of object recognition in simulated prosthetic vision. By using edge detection and zooming technique, the two processing strategies significantly improve the recognition accuracy of objects. We can conclude that the visual prosthesis using our proposed strategy can assist the blind to improve their ability to recognize objects. The results will provide effective solutions for the further development of visual prosthesis. PMID:29731769

21 CFR 878.3750 - External prosthesis adhesive.

Science.gov (United States)

2010-04-01

... used to fasten to the body an external aesthetic restoration prosthesis, such as an artificial nose. (b) Classification. Class I (general controls). The device is exempt from the premarket notification procedures in...

Development of a cosmetic knee disarticulation prosthesis : A single-patient case study

NARCIS (Netherlands)

de Laat, Fred A.; de Vos, Wouter; Geertzen, Jan; Roorda, Leo D.

2015-01-01

Background and aim: If a person does not become ambulant after an amputation, a knee disarticulation (KD) shouldbe considered and the person may then benefit from a cosmetic KD prosthesis. The features of a cosmetic KD prosthesis are, however, seldom described. The aim of this clinical note is to

21 CFR 888.3110 - Ankle joint metal/polymer semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ankle joint metal/polymer semi-constrained... Ankle joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an ankle...

Conception, design and development of a low-cost intelligent prosthesis for one-sided transfemoral amputees

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Wilson Carlos da Silva Júnior

Full Text Available Introduction Modern transfemoral knee prostheses are designed to offer comfort and self-confidence to amputees. These prostheses are mainly based upon either a passive concept, with a damping system, or an active computational intelligent design to control knee motion during the swing phase. In Brazil, most lower extremity amputees are unable to afford modern prostheses due to their high cost. In this work, we present the conception, design and development of a low-cost intelligent prosthesis for one-sided transfemoral amputees. Methods The concept of the prosthesis is based on a control system with sensors for loads, which are installed on the amputee’s preserved leg and used as a mirror for the movement of the prosthesis. Mechanical strength analysis, using the Finite Element Method, electromechanical tests for the sensors and actuators and verification of data acquisition, signal conditioning and data transferring to the knee prosthesis were performed. Results The laboratory tests performed showed the feasibility of the proposed design. The electromechanical concept that was used enabled a controlled activation of the knee prosthesis by the two load cells located on the shoe sole of the preserved leg. Conclusions The electromechanical design concept and the resulting knee prosthesis show promising results concerning prosthesis activation during walking tests, thereby showing the feasibility of a reduced manufacturing cost compared to the modern prostheses available on the market.

Self and partner satisfaction rates after 3 part inflatable penile prosthesis implantation.

Science.gov (United States)

Simsek, Abdulmuttalip; Kucuktopcu, Onur; Ozgor, Faruk; Ozkuvanci, Unsal; Baykal, Murat; Sarilar, Omer; Gurbuz, Zafer Gokhan

2014-09-30

To evaluate and present satisfaction rates of our patients and their partners after 3 part inflatable penile prosthesis implantation. We searched our hospital electronic data for patients who underwent inflatable penile prosthesis implantation between January 2008 and July 2013. Computer and archived file data were used to get information and reach the patients. We made telephone calls to patients and asked questionnaires about self and partner satisfaction rates. 36 patients underwent prosthesis implantation during the 5 year period. We were able to reach by telephone call 18 of them. The mean age of 18 patients was 55.7 ± 9.4 years and mean body mass index was 24.6 ± 2.1 kg/m2. The etiology was diabetes mellitus on 14 (77.8%) and radical pelvic surgery on 4 (22.2%) patients. 14 of 18 patients had penile Doppler ultrasound test. Doppler ultrasound demonstrated venous insufficiency in 8 and arterial insufficiency in 6 patients. Mean time from implantation to study was 20.8 ± 13.9 months. Out of 18 patients 2 had prosthesis removal operation because of infection in one patient and perforation in the other. Satisfaction rate was 88.9%, and recommendation rate was 94.4%. Causes of dissatisfaction were pain in one patient and insufficient rigidity plus shortening of the penis in the other one. Partner satisfaction rate was 94.4%. Penile Prosthesis Implantation (PPI) is the gold standard treatment of erectile dysfunction (ED) irresponsive to medical treatment. Infection and mechanical failure rates are going to be less according to the improvements in synthetic materials and coverings of the prosthesis, so patient and partner satisfaction rates will be higher.

A prosthesis-specific multi-link segment model of lower-limb amputee sprinting.

Science.gov (United States)

Rigney, Stacey M; Simmons, Anne; Kark, Lauren

2016-10-03

Lower-limb amputees commonly utilize non-articulating energy storage and return (ESAR) prostheses for high impact activities such as sprinting. Despite these prostheses lacking an articulating ankle joint, amputee gait analysis conventionally features a two-link segment model of the prosthetic foot. This paper investigated the effects of the selected link segment model׳s marker-set and geometry on a unilateral amputee sprinter׳s calculated lower-limb kinematics, kinetics and energetics. A total of five lower-limb models of the Ottobock ® 1E90 Sprinter were developed, including two conventional shank-foot models that each used a different version of the Plug-in-Gait (PiG) marker-set to test the effect of prosthesis ankle marker location. Two Hybrid prosthesis-specific models were then developed, also using the PiG marker-sets, with the anatomical shank and foot replaced by prosthesis-specific geometry separated into two segments. Finally, a Multi-link segment (MLS) model was developed, consisting of six segments for the prosthesis as defined by a custom marker-set. All full-body musculoskeletal models were tested using four trials of experimental marker trajectories within OpenSim 3.2 (Stanford, California, USA) to find the affected and unaffected hip, knee and ankle kinematics, kinetics and energetics. The geometry of the selected lower-limb prosthesis model was found to significantly affect all variables on the affected leg (p prosthesis-specific spatial, inertial and elastic properties from full-body models significantly affects the calculated amputee gait characteristics, and we therefore recommend the implementation of a MLS model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Maxillary palatal ramp prosthesis: A prosthodontic solution to manage mandibular deviation following surgery

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Sampa Ray (Bhattacharya

2015-01-01

Full Text Available Mandibular resection following surgical treatment for neoplastic lesions of the oral cavity leads to numerous complications including altered mandibular movements, disfigurement, difficult in swallowing, impaired speech and articulation, and deviation of the mandible towards the resected site. Various prosthetic methods are employed to reduce or minimize mandibular deviation and improve and restore the lost functions and esthetic, like maxillomandibular fixation, implant supported prosthesis, removable mandibular guide flange prosthesis, and palatal based guidance restoration. This clinical report describes the rehabilitation of a patient following segmental mandibulectomy using palatal ramp prosthesis.

A new and simple method of fabrication of tracheostomal prosthesis

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N Vidya Sankari

2015-01-01

Full Text Available Patients with a tracheostomy stoma experience compromised speech and function due to the associated changes in airflow patterns. Rehabilitation of a patient with tracheal stoma is a highly challenging task. The main objective is to design an inexpensive, easily fabricated stomal prosthesis for postlaryngectomy patients who require prolonged tracheotomy. This clinical case report describes a 29-year-old male patient who underwent for tracheotomy 3 months before for respiratory distress following a suicidal attempt. Hence tracheotomy was done, and the patient has been with the tracheostomal tube since surgery for the past 3 months. Laryngoscopy examination reported as restricted bilateral vocal cord movements, and the cords were in the adducted position with minimal glottic chink. No history of difficulty in swallowing. On examination, no scar or ulceration is seen around the stoma. The skin around the stoma is healthy. The patient was referred to the oral and maxillofacial Prosthodontics Department from the Department of ENT. The patient′s old tracheostomal tube was used as the dimensions of the custom made tracheal prosthesis without making a functional impression of the mature stoma. A tracheal button was made with 2 mm polyethylene urethane sheet to maintain the airway patency of the mature stoma. Width and length of the old tracheostomal tube were measured and customized with polyurethane sheet by directly flaming over heat. The finished product was thin, flexible, maintains enhanced tear strength, require no tapes or adhesives and less technique sensitive. These properties of the prosthesis make more advantageous than the commercially available tracheal buttons. The result in this patient was excellent with no postoperative complications. An innovative approach for fabrication of tracheostomal prosthesis was discussed to increase its successful use in tracheostomal patients. The patient′s old tracheostomal tube was used as the dimensions

Game-Based Rehabilitation for Myoelectric Prosthesis Control.

Science.gov (United States)

Prahm, Cosima; Vujaklija, Ivan; Kayali, Fares; Purgathofer, Peter; Aszmann, Oskar C

2017-02-09

A high number of upper extremity myoelectric prosthesis users abandon their devices due to difficulties in prosthesis control and lack of motivation to train in absence of a physiotherapist. Virtual training systems, in the form of video games, provide patients with an entertaining and intuitive method for improved muscle coordination and improved overall control. Complementary to established rehabilitation protocols, it is highly beneficial for this virtual training process to start even before receiving the final prosthesis, and to be continued at home for as long as needed. The aim of this study is to evaluate (1) the short-term effects of a commercially available electromyographic (EMG) system on controllability after a simple video game-based rehabilitation protocol, and (2) different input methods, control mechanisms, and games. Eleven able-bodied participants with no prior experience in EMG control took part in this study. Participants were asked to perform a surface EMG test evaluating their provisional maximum muscle contraction, fine accuracy and isolation of electrode activation, and endurance control over at least 300 seconds. These assessments were carried out (1) in a Pregaming session before interacting with three EMG-controlled computer games, (2) in a Postgaming session after playing the games, and (3) in a Follow-Up session two days after the gaming protocol to evaluate short-term retention rate. After each game, participants were given a user evaluation survey for the assessment of the games and their input mechanisms. Participants also received a questionnaire regarding their intrinsic motivation (Intrinsic Motivation Inventory) at the end of the last game. Results showed a significant improvement in fine accuracy electrode activation (Pgames when collecting items and facing challenging game play. Most upper limb amputees use a 2-channel myoelectric prosthesis control. This study demonstrates that this control can be effectively trained by

[Tripolar arthroplasty for recurrent total hip prosthesis dislocation].

Science.gov (United States)

Beaulé, P-E; Roussignol, X; Schmalzried, T-P; Udomkiat, P; Amstutz, H-C; Dujardin, F-H

2003-05-01

The purpose of this study was to assess the results of revision surgery for recurrent total hip prosthesis dislocation using a tripolar prosthesis composed of a conventional stem with a mobile head of an intermediary prosthesis measuring more than 40 mm and a modified cup. This technique was used in two centers in Rouen France and Los Angeles USA. Twenty-one hips in 21 patients were operated on. The mobile heads measured 40 to 47 mm. Mean patient age was 70 years (range 29-92). The indication for the tripolar prosthesis was reserved for extremely unstable hips in patients with major risk factors for recurrent dislocation. These 21 patients had experienced 95 dislocations. The acetabular cup was custom-made for the large-diameter heads. A cemented polyethylene cup was used in 14 cases and a press-fit metal-backed around a polyethylene insert in 7. The polyethylene thickness varied from 6.5 to 16 mm for the cemented cups and 4 to 5 mm for the press-fit cups. Fourteen femoral stems were left in place as were two press-fit cups where only the inserts were changed. Mean follow-up was 5.4 years (range 3-11.8). There has been no recurrent dislocation for 20 hips. One patient experienced a dislocation one week after surgery which required a second revision procedure to reposition the acetabular implant. Final outcome was good at 7.6 years for this hip. One patient who had not had any recurrent dislocation died 4 years after the revision surgery due to a cause unrelated to the prosthesis. Two patients were lost to follow-up at 3.7 and 6 years, both were pain free and had no radiological anomalies. Infection occurred in one patient undergoing chemotherapy for a myeloma; the head and neck had to be resected. For the 20 other patients, functional outcome, assessed with the UCLA score, showed improvement in pain (5.8 preoperatively, 9.2 at last follow-up), walking (4.8 and 8 respectively), function (4 and 6 respectively), and daily activities (3.3 and 5.2 respectively). A

An Underreported Consequence of Obesity in Pregnancy: Patient-Prosthesis Mismatch

OpenAIRE

Hartman, William R.; Arendt, Katherine W.; Rehfeldt, Kent H.

2012-01-01

As the rate of obesity increases in childbearing-aged women, so too will the complications of obesity in pregnancy. An uncommon and likely underreported complication occurs in obese women who have received prepregnancy cardiac valve replacement with a prosthesis that is inadequately sized for body habitus, a condition referred to as patient-prosthesis mismatch (PPM). The physiologic changes of pregnancy as well as the increased weight gain combine to exacerbate PPM. We report a case of PPM th...

A custom-made temporomandibular joint prosthesis for fabrication by selective laser melting: Finite element analysis.

Science.gov (United States)

Xu, Xiangliang; Luo, Danmei; Guo, Chuanbin; Rong, Qiguo

2017-08-01

A novel and custom-made selective laser melting (SLM) 3D-printed alloplastic temporomandibular joint (TMJ) prosthesis is proposed. The titanium-6aluminium-4vanadium (Ti-6Al-4V) condyle component and ultra-high molecular weight polyethylene (UHMWPE) fossa component comprised the total alloplastic TMJ replacement prosthesis. For the condyle component, an optimized tetrahedral open-porous scaffold with combined connection structures, i.e. an inlay rod and an onlay plate, between the prosthesis and remaining mandible was designed. The trajectory of movement of the intact condyle was assessed via kinematic analysis to facilitate the design of the fossa component. The behaviours of the intact mandible and mandible with the prosthesis were compared. The biomechanical behaviour was analysed by assessing the stress distribution on the prosthesis and strain distribution on the mandible. After muscle force was applied, the magnitude of the compressive strain on the condyle neck of the mandible with the prosthesis was lower than that on the condyle neck of the intact mandible, with the exception of the area about the screws; additionally, the magnitude of the strain at the scaffold-bone interface was relatively high. Copyright © 2017. Published by Elsevier Ltd.

Elektra prosthesis for trapeziometacarpal osteoarthritis

DEFF Research Database (Denmark)

Klahn, A; Nygaard, Mads; Gvozdenovic, R

2012-01-01

We present a prospective follow-up of 39 Elektra prostheses in 37 patients (32 women and five men), with a mean age of 56.5 (range 46-71) years; 34 patients had osteoarthritis and three had rheumatoid arthritis. Patients were followed using clinical examination, including measurement of pain...... be the key problem in treating trapeziometacarpal osteoarthritis using a total prosthesis....

A unique method of retaining orbital prosthesis with attachment systems - a clinical report.

Science.gov (United States)

Guttal, Satyabodh S; Akash, N R; Prithviraj, D R; Lekha, K

2014-06-01

Diminution of the orbital contents post-surgical removal of a malignant tumor can have a severe psychological impact on the patient in terms of function and esthetics. Therefore, esthetic remedy should be planned subsequently, since tumor obliteration precedes cosmetic concern. A convenient option for successful rehabilitation in such patients is a simple, user-friendly, removable orbital prosthesis. Retention of the prosthesis is one of the key factors for the successful rehabilitation. Spectacle frame, conformers, adhesives, osseointegrated implants, magnets or buttons have been used to impart retention to the prosthesis. The use of semi precision attachments in maxillofacial prostheses is limited to the osseointegrated prostheses. This case report describes a conventional spectacle frame technique, to retain the silicone orbital prosthesis using two different types of stud attachments viz., dalla bona and O-ring attachment systems. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Customization of stock eye prosthesis for a pediatric patient by a simplified technique.

Science.gov (United States)

Jurel, Sunit Kumar; Talwar, Naina; Chand, Pooran; Singh, Raghuwar D; Gupta, Durga Shanker

2012-05-01

The unfortunate loss or absence of an eye may be caused by congenital defect , irreparable trauma, tumor or blind eye. The role of the maxillofacial prosthodontist in fabricating an ocular prosthesis to restore facial symmetry and normal appearance for the anophthalmic patient becomes essential. A custom-made ocular prosthesis is an excellent alternative for the people who lose their eye especially in young age. It has acceptable fit, retention and esthetics but is technically difficult to fabricate. On the other hand the stock eye has compromised fit and poor esthetics. Our case report presents a simple technique of customization of stock eye prosthesis to provide accurate fit and acceptable esthetics. How to cite this article: Jurel SK, Talwar N, Chand P, Singh RD, Gupta DS. Customization of Stock Eye Prosthesis for a Pediatric Patient by a Simplified Technique. Int J Clin Pediatr Dent 2012;5(2):155-158.

Difference in occurrence of heterotopic ossification according to prosthesis type in the cervical artificial disc replacement.

Science.gov (United States)

Yi, Seong; Kim, Keung Nyun; Yang, Moon Sul; Yang, Joong Won; Kim, Hoon; Ha, Yoon; Yoon, Do Heum; Shin, Hyun Chul

2010-07-15

Retrospective study of the difference of heterotopic ossification (HO) occurrence according to 3 different types of prosthesis. This study was designed to investigate the difference of HO occurrence according to different type of prosthesis. HO is defined as formation of the bone outside the skeletal system. Reported HO occurrence rate in cervical artificial disc replacement (ADR) was unexpectedly high and varied. But the influencing factors of HO in cervical ADR have not been elucidated well. The prosthesis-related factors for making difference of HO occurrence were investigated in this study. A total of 170 patients undergoing cervical arthroplasty with the Bryan cervical disc prosthesis (Medtroic Sofamor Danek, Memphis, TN), Mobi-C disc prosthesis (LDR Medical, Troyes, France), and ProDisc-C (Synthes, Inc., West Chester, PA) were included. Cervical lateral radiographs obtained before and after surgery were used to identify HO. Occurrence rate, occurrence-free period, location, and grade of HOs were investigated according to the different prosthesis. Each prosthesis group included patients as follows: Bryan disc, 81 patients; Mobi-C, 61 patients; and ProDisc-C, 28 patients. Overall HO rate was 40.6% (69 of 170 patients). Each HO occurrence rate by prosthesis was as follows: the Bryan disc group, 21.0%; Mobi-C group, 52.5%; and the ProDisc-C group, 71.4%. In the survival analysis, all patients showed 27.1 +/- 3.7 months as the median survival. The Bryan disc group showed statistically longer survival (48.4 +/- 7.4 months) than the other groups. Occurrence of HO is an inevitable postoperative complication after cervical ADR. The occurrence rate of HO was higher than our expectation. Moreover, definite differences in occurrence rate according to the prosthesis type were identified by this study.

Influence of type of aortic valve prosthesis on coronary blood flow velocity.

Science.gov (United States)

Jelenc, Matija; Juvan, Katja Ažman; Medvešček, Nadja Tatjana Ružič; Geršak, Borut

2013-02-01

Severe aortic valve stenosis is associated with high resting and reduced hyperemic coronary blood flow. Coronary blood flow increases after aortic valve replacement (AVR); however, the increase depends on the type of prosthesis used. The present study investigates the influence of type of aortic valve prosthesis on coronary blood flow velocity. The blood flow velocity in the left anterior descending coronary artery (LAD) and the right coronary artery (RCA) was measured intraoperatively before and after AVR with a stentless bioprosthesis (Sorin Freedom Solo; n = 11) or a bileaflet mechanical prosthesis (St. Jude Medical Regent; n = 11). Measurements were made with an X-Plore epicardial Doppler probe (Medistim, Oslo, Norway) following induction of hyperemia with an adenosine infusion. Preoperative and postoperative echocardiography evaluations were used to assess valvular and ventricular function. Velocity time integrals (VTI) were measured from the Doppler signals and used to calculate the proportion of systolic VTI (SF), diastolic VTI (DF), and normalized systolic coronary blood flow velocities (NSF) and normalized diastolic coronary blood flow velocities (NDF). The systolic proportion of the LAD VTI increased after AVR with the St. Jude Medical Regent prosthesis, which produced higher LAD SF and NSF values than the Sorin Freedom Solo prosthesis (SF, 0.41 ± 0.09 versus 0.29 ± 0.13 [P = .04]; NSF, 0.88 ± 0.24 versus 0.55 ± 0.17 [P = .01]). No significant changes in the LAD velocity profile were noted after valve replacement with the Sorin Freedom Solo, despite a significant reduction in transvalvular gradient and an increase in the effective orifice area. AVR had no effect on the RCA flow velocity profile. The coronary flow velocity profile in the LAD was significantly influenced by the type of aortic valve prosthesis used. The differences in the LAD velocity profile probably reflect differences in valve design and the systolic transvalvular flow pattern.

Self and partner satisfaction rates after 3 part inflatable penile prosthesis implantation

Directory of Open Access Journals (Sweden)

Abdulmuttalip Simsek

2014-09-01

Full Text Available Objective: To evaluate and present satisfaction rates of our patients and their partners after 3 part inflatable penile prosthesis implantation. Materials and methods: We searched our hospital electronic data for patients who underwent inflatable penile prosthesis implantation between January 2008 and July 2013. Computer and archived file data were used to get information and reach the patients. We made telephone calls to patients and asked questionnaires about self and partner satisfaction rates. Results: 36 patients underwent prosthesis implantation during the 5 year period. We were able to reach by telephone call 18 of them. The mean age of 18 patients was 55.7 ± 9.4 years and mean body mass index was 24.6 ± 2.1 kg/m2. The etiology was diabetes mellitus on 14 (77.8% and radical pelvic surgery on 4 (22.2% patients. 14 of 18 patients had penile Doppler ultrasound test. Doppler ultrasound demonstrated venous insufficiency in 8 and arterial insufficiency in 6 patients. Mean time from implantation to study was 20.8 ± 13.9 months. Out of 18 patients 2 had prosthesis removal operation because of infection in one patient and perforation in the other. Satisfaction rate was 88.9%, and recommendation rate was 94.4%. Causes of dissatisfaction were pain in one patient and insufficient rigidity plus shortening of the penis in the other one. Partner satisfaction rate was 94.4%. Conclusion: Penile Prosthesis Implantation (PPI is the gold standard treatment of erectile dysfunction (ED irresponsive to medical treatment. Infection and mechanical failure rates are going to be less according to the improvements in synthetic materials and coverings of the prosthesis, so patient and partner satisfaction rates will be higher.

A study to assess whether fixed-width beam walking provides sufficient challenge to assess balance ability across lower limb prosthesis users.

Science.gov (United States)

Sawers, Andrew; Hafner, Brian J

2018-04-01

To evaluate the feasibility of fixed-width beam walking for assessing balance in lower limb prosthesis users. Cross-sectional. Laboratory. Lower limb prosthesis users. Participants attempted 10 walking trials on three fixed-width beams (18.6, 8.60, and 4.01 wide; 5.5 m long; 3.8 cm high). Beam-walking performance was quantified using the distance walked to balance failure. Heuristic rules applied to each participant's beam-walking distance to classify each beam as "too easy," "too hard," or "appropriately challenging" and determine whether any single beam provided an appropriate challenge to all participants. The number of trials needed to achieve stable beam-walking performance was quantified for appropriately challenging beams by identifying the last inflection point in the slope of each participant's trial-by-trial cumulative performance record. In all, 30 unilateral lower limb prosthesis users participated in the study. Each of the fixed-width beams was either too easy or too hard for at least 33% of the sample. Thus, no single beam was appropriately challenging for all participants. Beam-walking performance was stable by trial 8 for all participants and by trial 6 for 90% of participants. There was no significant difference in the number of trials needed to achieve stable performance among beams ( P = 0.74). Results suggest that a clinical beam-walking test would require multiple beams to evaluate balance across a range of lower limb prosthesis users, emphasizing the need for adaptive or progressively challenging balance tests. While the administrative burden of a multiple-beam balance test may limit clinical feasibility, alternatives to ease this administrative burden are proposed.

Hip arthroplasty. Part 1: prosthesis terminology and classification

International Nuclear Information System (INIS)

Pluot, E.; Davis, E.T.; Revell, M.; Davies, A.M.; James, S.L.J.

2009-01-01

Hip arthroplasty is an extremely common orthopaedic procedure and there is a wide array of implants that are in current use in the UK. The follow-up of patients who have undergone insertion of a hip prosthesis is shifting from a consultant-lead hospital service towards primary care. As this change in patient care continues it becomes increasingly important that an accurate description of the radiographic features is communicated to the primary-care practitioner so appropriate specialist input can be triggered. This review focuses on the terminology and classification of hip prostheses. This acts as a precursor for Part 2 of this series, which describes the normal and abnormal radiographic findings following hip prosthesis insertion.

A Biomimetic Approach for Designing a Full External Breast Prosthesis: Post-Mastectomy

Directory of Open Access Journals (Sweden)

Pedro Cruz

2018-03-01

Full Text Available This work presents the design of a new breast prosthesis using the biomimetic technique for cases of complete mastectomy to address the problem of the increasing number of women diagnosed with breast cancer in Mexico who are candidates for a mastectomy. The designed prosthesis considers the morphology of a real breast regarding its internal structure to obtain authentic mobility and feel. In order to accomplish this, a model was obtained in 3D CAD using a coordinate measuring machine (CMM that can be scalable without losing its qualities, and which can be used in any type of patient; afterwards, a finite element model was developed and a static analysis performed with suggested load cases to evaluate the sensitivity and naturalness of the prosthesis; and finally, a modal analysis was conducted. The results obtained in displacements and in distribution of stress for the load cases assessed are consistent with those of a real breast: there were smooth contours and there was natural mobility in the prosthesis designed by means of the biomimetic technique.

21 CFR 888.3565 - Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemorotibial metal/polymer... Devices § 888.3565 Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis. (a) Identification. A knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis is a device...

21 CFR 888.3550 - Knee joint patellofemorotibial polymer/metal/metal constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemorotibial polymer/metal/metal... § 888.3550 Knee joint patellofemorotibial polymer/metal/metal constrained cemented prosthesis. (a) Identification. A knee joint patellofemorotibial polymer/metal/metal constrained cemented prosthesis is a device...

21 CFR 888.3490 - Knee joint femorotibial metal/composite non-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/composite non... § 888.3490 Knee joint femorotibial metal/composite non-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/composite non-constrained cemented prosthesis is a device...

Eliciting Naturalistic Cortical Responses with a Sensory Prosthesis via Optimized Microstimulation

Science.gov (United States)

2016-08-12

Eliciting naturalistic cortical responses with a sensory prosthesis via optimized microstimulation John S Choi1, Austin J Brockmeier2, David B...applied to single electrodes in the ventral caudal thalamus evoke percepts that are both place and modality-specific, and yet ‘unnatural’ in feeling ...information on touch parameters, they do so with the same timing, as would be expected for a biomimetic sensory prosthesis . The discriminability of natural

Restoring Proprioception via a Cortical Prosthesis: A Novel Learning Based Approach

Science.gov (United States)

2016-10-01

AWARD NUMBER: W81XWH-14-1-0510 TITLE: Restoring Proprioception via a Cortical Prosthesis : A Novel Learning-Based Approach PRINCIPAL INVESTIGATOR...Sep 2015 - 29 Sep 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Restoring Proprioception via a Cortical Prosthesis : A Novel Learning-Based...the feeling of where the body is in space. The importance of proprioception is often not appreciated; without it, we are unable to move normally

An experimental-numerical method for comparative analysis of joint prosthesis

International Nuclear Information System (INIS)

Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

2001-01-01

The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs

21 CFR 888.3530 - Knee joint femorotibial metal/polymer semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/polymer semi... § 888.3530 Knee joint femorotibial metal/polymer semi-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/polymer semi-constrained cemented prosthesis is a device intended...

21 CFR 888.3540 - Knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemoral polymer/metal semi... § 888.3540 Knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis. (a) Identification. A knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis is a two-part...

21 CFR 888.3500 - Knee joint femorotibial metal/composite semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/composite semi... § 888.3500 Knee joint femorotibial metal/composite semi-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/composite semi-constrained cemented prosthesis is a two-part...

21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be implanted...

21 CFR 888.3520 - Knee joint femorotibial metal/polymer non-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/polymer non... § 888.3520 Knee joint femorotibial metal/polymer non-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/polymer non-constrained cemented prosthesis is a device intended to...

21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made of...

Usefulness of positron emission tomography (TEP) in the assessment of osteo-articular prosthesis

International Nuclear Information System (INIS)

Maldonado, A.; Suarez, J.P.; Dominguez, M.L.

2004-01-01

Joint arthroplasty is performed with increasing frequency as the population ages. Loosening or infection of the prosthesis is a relatively common event that can limit the lifetime of a prosthesis. Accuracy differentiation between aseptic and septic loosening of the prosthesis remains a challenge because of the consequences for patient management. Moreover, an early diagnosis of infected hip prosthesis is very important for optimal and cost-effective management. Various approaches have developed to visualize infection and inflammation by nuclear medicine techniques. Recently positron emission tomography (PET) with fluorine-l8 labelled 2 fluoro-2-deoxyglucose ( 18 F-FDG) has been shown to delineate infectious and inflammatory foci with high sensitivity owing to the increased glucose metabolism in inflammatory cells. In this paper we review the role of FDG-PET in this common differential diagnosis in patients with total knee and hip prostheses. Different patterns of FDG-PET interpretation have been described as wed as methodological aspects. (author)

[Phonomechanocardiography in the evaluation of the functional status of valvular prosthesis].

Science.gov (United States)

Esquivel Avila, J; Molina Zapata, B; Martínez Ríos, M A; Flamand, E

1975-01-01

The FMCG in 22 patients with valvular prosthesis is analyzed and its clinical, hemodynamic and surgical correlation are established (11 from the I.N.C. and 11 from the Hospital Infantil I.M.A.N.). The average age of the patients was 15 years old, 18 had a mitral and six aortic valvulopathy, and they all required a valvular replacement. Of the mitral prosthesis, 14 were Starr-Edwards (13 of ball valve and one of disc), three Lillehei-Kaster and one Börck-Shiley. In 5 patients, the FMCG suspected disfunction that was later corroborated by catheterism in three patients and by surgery in all of them. The important differences of the FMCG between the group with good and the one with bad function were: the aparition of a rumble, a decrease in the amplitud of the closing snap, index of closing snap opering snap of less than one, lenghtening of fases PFVP and IVCP, and shortening of IVDRP. In the patients with auricular fibrilation, after long dyastoles; that would represent an adequate atrial emptying; the closing snap was more intense, the PFVP was lennthened the IVDRP was shortened when the prosthesis was not properly functioning. All the aortic prosthesis were ball valve Starr-Edwards type; in one the FMCG suspected disfunction and the patient had a sudden death outside of the Hospital. The significant differences of the FMCG were the decrease in the intensity of the opening snap, with a Hylen index of less than one, lengthening of the PFVP, IVCP and of the expulsive period (EP). The authors conclude that the FMCG is a good method for an early detection of the disfunctions of valvular prosthesis.

Quality of life among lower limb prosthesis users attending Artificial Limb Center of Fauji Foundation Hospital Rawalpindi

International Nuclear Information System (INIS)

Kalsoom, U.; Bairam, S.

2018-01-01

To assess quality of life and the influencing factors as perceived by lower limb prosthesis users. Study Design: Cross sectional study. Place and Duration of Study: Artificial Limb Centre, Fauji Foundation Hospital Rawalpindi, 11 months (Jan to Nov 2014). Material and Methods: A sample of 50 patients with lower limb amputations and using lower limb prosthesis were recruited by applying inclusion criteria. Responses were recorded on demographic variables, reasons for amputation, time of provision of prosthesis, employment status etc. by the investigator on a structured pretested questionnaire after their consent. A p-value of <0.05 was taken as significant. Quality of life was interpreted on 5 point Likert scale. Data was analyzed in SPSS version 21. Result: Majority of respondents i.e. 17 (34%) were in 51-60 years age group with mean age 46 +- 14 years while 33 (66%) were males and 27 (54%) illiterate, 33 (66%) could afford a prosthesis. Trauma 28 (56%) was the most prevalent cause of lower limb amputation and among them 15 (53%) had road accident injuries. Various factors influenced quality of life as perceived by the respondents and in 10 (20%), 16 (32%), 25 (50%) social, family life and emotional status was affected respectively, while 14 (28%) of the prosthesis user were unemployed. Prosthesis were provided after 2 years in 18 (36%) and in 37 (74%) prosthesis were provided by the health care facility. Good quality of life was perceived in 40 (80%) respondents. Conclusion: Perceived Quality of life was good in majority of the prosthesis users but others can't be ignored. It can be improved by early provision of prosthesis which can help in better employment opportunities. (author)

Experimental Assessment of a New Type of Carbon-Coated ARTECOR® Vascular Prosthesis in Sheep

Directory of Open Access Journals (Sweden)

Jiří Podlaha

2009-01-01

Full Text Available The aim of the study was to test and verify the characteristics of a new type of carbon-coated ARTECOR® vascular prosthesis developed at the Knitting Research Institute, a.s. Brno. Eight healthy Merino sheep, aged between 2 and 3 years, were implanted four types (A, B, C with diamond-like carbon (DLC coating and D as a control without DLC of vascular prostheses. The site of implantation was the common carotid artery; the length of the implant was 7 cm. All sheep received antibiotics prophylactically in accordance with the theory of the so-called “protected coagulum”. Doppler ultrasound examination was performed before finishing the operation to verify the patency of each prosthesis. During the study period the animals were closely observed. Prostheses were extirpated on day +/- 100 in 6 sheep and on day 182 in 2 sheep. Type B prosthesis showed better results according to its postoperative patency. The implant lumen was constantly 7 mm, whereas the use of other types resulted in lumen narrowing. Type B prosthesis has a deposition of DLC coating of a thickness of 20 nm with a high content of sp3 bonds (more diamond-like ones. The experimental type B of prosthesis ARTECOR® appears to be the most successful of the tested prostheses (at the end of the study all B-type prostheses remained patent. This prosthesis appears to better satisfy the rheologic characteristics for healing.

Restoring Proprioception via a Cortical Prosthesis: A Novel Learning-Based Approach

Science.gov (United States)

2015-10-01

AWARD NUMBER: W81XWH-14-1-0510 TITLE: Restoring Proprioception via a Cortical Prosthesis : A Novel Learning-Based Approach PRINCIPAL INVESTIGATOR...Proprioception via a Cortical Prosthesis : A Novel Learning-Based Approach 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Philip Sabes, PhD 5d...component of this lost sensation is proprioception, the feeling of where the body is in space. The importance of proprioception is often not appreciated

Clinical experience with an alloplastic stoma prosthesis (Biocarbon) for urinary conduits and cutaneous ureterostomy.

Science.gov (United States)

Månsson, W; Harzmann, R

1988-01-01

An alloplastic stoma prosthesis, Biocarbon, composed of 99.9% pure carbon in vitreous form, was used in six patients with conduit urinary diversion and in seven with cutaneous ureterostomy. The patients were thereafter observed for 2-86 months. Complications were subcutaneous infection, urinary fistula and ureteral stenosis, which necessitated removal of the prosthesis in most cases. The permanent stoma, without need for adhesive collecting device, was appreciated by the patients. Problems relating to biocompatibility remain to be solved before the place of the stoma prosthesis in urinary diversion can be determined.

Effect of breast augmentation after breast-conserving surgery for breast cancer on radiation dose. Silicone prosthesis and changes in radiation dose

International Nuclear Information System (INIS)

Tonari, Ayako; Nako, Yasunobu; Ikezaki, Hiromi; Maruyama, Yasushi; Ikeda, Ikuo; Kusuda, Junko; Harii, Kiyonori; Takayama, Makoto

2008-01-01

The results of a study simulating postoperative radiation therapy of remaining breast tissue with a silicone bag prosthesis implanted to examine the effects of the prosthesis on radiation dosage and surrounding tissue are reported. The evaluation was conducted in two stages: a water phantom was used to evaluate scattering effects of a prosthesis installed inside the phantom using glass rod detector (GRD) set around the prosthesis. Measurements were conducted on both entrance and rear sides of the prosthesis. A Rand phantom was used to measure radiation doses around the prosthesis. The first evaluation resulted in a less than 5.4% reduction in dose at the rear side of the prosthesis whereas the second evaluation, for opposing portal irradiation used with breast-conserving surgical treatment, showed the effects of the prosthesis on radiation dosage being within ±2%, the permitted treatment range. In conclusion, for treating breast cancer, combining surgical treatment of the cancer with implanting of prosthesis for breast reconstruction followed by radiation treatment appears feasible as no effects on dosage were observed on treatment effectiveness. (author)

A cognitive prosthesis for complex decision-making.

Science.gov (United States)

Tremblay, Sébastien; Gagnon, Jean-François; Lafond, Daniel; Hodgetts, Helen M; Doiron, Maxime; Jeuniaux, Patrick P J M H

2017-01-01

While simple heuristics can be ecologically rational and effective in naturalistic decision making contexts, complex situations require analytical decision making strategies, hypothesis-testing and learning. Sub-optimal decision strategies - using simplified as opposed to analytic decision rules - have been reported in domains such as healthcare, military operational planning, and government policy making. We investigate the potential of a computational toolkit called "IMAGE" to improve decision-making by developing structural knowledge and increasing understanding of complex situations. IMAGE is tested within the context of a complex military convoy management task through (a) interactive simulations, and (b) visualization and knowledge representation capabilities. We assess the usefulness of two versions of IMAGE (desktop and immersive) compared to a baseline. Results suggest that the prosthesis helped analysts in making better decisions, but failed to increase their structural knowledge about the situation once the cognitive prosthesis is removed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stress distribution in dental prosthesis under an occlusal combined dynamic loading

International Nuclear Information System (INIS)

Merdji, A.; Bachir Bouiadjra, B.; Ould Chikh, B.; Mootanah, R.; Aminallah, L.; Serier, B.; Muslih, I.M.

2012-01-01

Highlights: ► The mechanical stress reaches the highest in areas of cortical bones. ► The mechanical stress in the cancellous bone reaches greatest in the bottom of the dental implant. ► Implant with low-volume bone might cause increased stress concentration in the cortical bone. -- Abstract: The biomechanical behavior of osseointegrated dental prostheses systems plays an important role in its functional longevity inside the bone. Simulation of these systems requires an accurate modeling of the prosthesis components, the jaw bone, the implant–bone interface, and the response of the system to different types of applied forces. The purpose of this study was to develop a new three-dimensional model of an osseointegrated molar dental prosthesis and to carry out finite element analysis to evaluate stress distributions in the bone and the dental prosthesis compounds under an occlusal combined dynamic load was applied to the top of the occlusale face of the prosthesis crown. The jaw bone model containing cortical bone and cancellous bone was constructed by using computer tomography scan pictures and Computer Aided Design tools. The dental prosthesis compounds were constructed, simulating the commercially available cylindrical implant of 4.8 mm diameter and 10 mm length. Both finite element models were created in Abaqus finite element software. All materials used in the models were considered to be isotropic, homogeneous and linearly elastic. The elastic properties, loads and constraints used in the model were taken from published data. Results of our finite element analyses, indicated that the maximum stresses were located around the mesial neck of the implant, in the marginal bone. Thus, this area should be preserved clinically in order to maintain the bone–implant interface structurally and functionally.

A simplified approach to fabrication of an ocular prosthesis: A case series

Directory of Open Access Journals (Sweden)

Kaur Amandeep

2010-01-01

Full Text Available The eye is a vital organ and an important component of facial expression. Loss of an eye has a crippling effect on the psychology of the patient. Enucleation of the eye is therefore normally followed by fabrication of an ocular prosthesis to improve esthetics. A less complex technique for fabrication of an ocular prosthesis is described in this report of two different cases.

Visual prosthesis wireless energy transfer system optimal modeling.

Science.gov (United States)

Li, Xueping; Yang, Yuan; Gao, Yong

2014-01-16

Wireless energy transfer system is an effective way to solve the visual prosthesis energy supply problems, theoretical modeling of the system is the prerequisite to do optimal energy transfer system design. On the basis of the ideal model of the wireless energy transfer system, according to visual prosthesis application condition, the system modeling is optimized. During the optimal modeling, taking planar spiral coils as the coupling devices between energy transmitter and receiver, the effect of the parasitic capacitance of the transfer coil is considered, and especially the concept of biological capacitance is proposed to consider the influence of biological tissue on the energy transfer efficiency, resulting in the optimal modeling's more accuracy for the actual application. The simulation data of the optimal model in this paper is compared with that of the previous ideal model, the results show that under high frequency condition, the parasitic capacitance of inductance and biological capacitance considered in the optimal model could have great impact on the wireless energy transfer system. The further comparison with the experimental data verifies the validity and accuracy of the optimal model proposed in this paper. The optimal model proposed in this paper has a higher theoretical guiding significance for the wireless energy transfer system's further research, and provide a more precise model reference for solving the power supply problem in visual prosthesis clinical application.

False-positive indium-111 labeled leukocyte scintigram in a patient with a painful hip prosthesis

International Nuclear Information System (INIS)

Feldman, N.; Makler, P.T. Jr.; Alavi, A.

1986-01-01

A Tronzo hip prosthesis is designed to elicit an inflammatory reaction in order to promote prosthesis stability. A three-phased bone scan and Ga-67 imaging in conjunction with physical examination and laboratory findings failed to demonstrate evidence for osteomyelitis in a patient with a painful hip prosthesis, in whom images obtained with In-111-labeled leukocytes were positive. This observation demonstrated that the interpretation of the latter technique in demonstrating inflammation can cause a false impression of an infectious process

Nontraumatic Fracture of the Femoral Condylar Prosthesis in a Total Knee Arthroplasty Leading to Mechanical Failure

Directory of Open Access Journals (Sweden)

Girish N. Swamy

2014-01-01

Full Text Available This paper reports a case of fatigue fracture of the femoral component in a cruciate-retaining cemented total knee arthroplasty (TKA. A 64-year-old man had undergone a primary TKA for osteoarthritis 10 years previously at another institution using the PFC-Sigma prosthesis. The patient recovered fully and was back to his regular activities. He presented with a history of sudden onset pain and locking of the left knee since the preceding three months. There was no history of trauma, and the patient was mobilizing with difficulty using crutches. Radiographs revealed fracture of the posterior condyle of the femoral prosthesis. Revision surgery was performed as an elective procedure revealing the broken prosthesis. The TC3RP-PFC revision prosthesis was used with a medial parapatellar approach. The patient recovered fully without any squeal. Mechanical failure of the knee arthroplasty prosthesis is rare, and nontraumatic fracture of the femoral metallic component has not been reported before.

Nontraumatic fracture of the femoral condylar prosthesis in a total knee arthroplasty leading to mechanical failure.

Science.gov (United States)

Swamy, Girish N; Quah, Conal; Bagouri, Elmunzar; Badhe, Nitin P

2014-01-01

This paper reports a case of fatigue fracture of the femoral component in a cruciate-retaining cemented total knee arthroplasty (TKA). A 64-year-old man had undergone a primary TKA for osteoarthritis 10 years previously at another institution using the PFC-Sigma prosthesis. The patient recovered fully and was back to his regular activities. He presented with a history of sudden onset pain and locking of the left knee since the preceding three months. There was no history of trauma, and the patient was mobilizing with difficulty using crutches. Radiographs revealed fracture of the posterior condyle of the femoral prosthesis. Revision surgery was performed as an elective procedure revealing the broken prosthesis. The TC3RP-PFC revision prosthesis was used with a medial parapatellar approach. The patient recovered fully without any squeal. Mechanical failure of the knee arthroplasty prosthesis is rare, and nontraumatic fracture of the femoral metallic component has not been reported before.

Carbon/PEEK composite materials as an alternative for stainless steel/titanium hip prosthesis: a finite element study.

Science.gov (United States)

Rezaei, Farshid; Hassani, Kamran; Solhjoei, Nosratollah; Karimi, Alireza

2015-12-01

Total hip replacement (THR) has been ranked within the most typical surgical processes in the world. The durability of the prosthesis and loosening of prosthesis are the main concerns that mostly reported after THR surgeries. In THR, the femoral prosthesis can be fixed by either cement or cementless methods in the patient's bones. In both procedures, the stability of the prosthesis in the hosted bone has a key asset in its long-term durability and performance. This study aimed to execute a comparative finite element simulation to assess the load transfer between the prosthesis, which is made of carbon/PEEK composite and stainless steel/titanium, and the femur bone. The mechanical behavior of the cortical bone was assumed as a linear transverse isotropic while the spongy bone was modeled like a linear isotropic material. The implants were made of stainless steel (316L) and titanium alloy as they are common materials for implants. The results showed that the carbon/PEEK composites provide a flatter load transfer from the upper body to the leg compared to the stainless steel/titanium prosthesis. Furthermore, the results showed that the von Mises stress, principal stress, and the strain in the carbon/PEEK composites prosthesis were significantly lower than that made of the stainless steel/titanium. The results also imply that the carbon/PEEK composites can be applied to introduce a new optimum design for femoral prosthesis with adjustable stiffness, which can decrease the stress shielding and interface stress. These findings will help clinicians and biomedical experts to increase their knowledge about the hip replacement.

Development and performance of a new prosthesis system using ultrasonic sensor for wrist movements: a preliminary study

Science.gov (United States)

2014-01-01

Background The design and performance of a new development prosthesis system known as biomechatronics wrist prosthesis is presented in this paper. The prosthesis system was implemented by replacing the Bowden tension cable of body powered prosthesis system using two ultrasonic sensors, two servo motors and microcontroller inside the prosthesis hand for transradial user. Methods The system components and hand prototypes involve the anthropometry, CAD design and prototyping, biomechatronics engineering together with the prosthetics. The modeler construction of the system develop allows the ultrasonic sensors that are placed on the shoulder to generate the wrist movement of the prosthesis. The kinematics of wrist movement, which are the pronation/supination and flexion/extension were tested using the motion analysis and general motion of human hand were compared. The study also evaluated the require degree of detection for the input of the ultrasonic sensor to generate the wrist movements. Results The values collected by the vicon motion analysis for biomechatronics prosthesis system were reliable to do the common tasks in daily life. The degree of the head needed to bend to give the full input wave was about 45° - 55° of rotation or about 14 cm – 16 cm. The biomechatronics wrist prosthesis gave higher degree of rotation to do the daily tasks but did not achieve the maximum degree of rotation. Conclusion The new development of using sensor and actuator in generating the wrist movements will be interesting for used list in medicine, robotics technology, rehabilitations, prosthetics and orthotics. PMID:24755242

Osseointegrated silicone finger prosthesis using dental implants: a renovated technique.

Science.gov (United States)

Vinnakota, Dileep Nag; Sankar, V Vijay; Chirumamilla, Naveen; Reddy, V Vamsikrishna

2014-11-01

In clinical practice, we come across patients with traumatically amputated or congenitally missing partial or complete fingers that can be restored using microsurgical replantation or transplantation procedures. However, in some cases this might not be possible due to systemic or local factors and the lost or missing part has to be replaced prosthetically to offer psychological and functional wellbeing. These prostheses can be constructed with various materials like acrylics or silicone retained with the help of auxiliary aids. However, these prostheses cause some hindrance in performing functions like writing, typing, etc. The aim of the present trial was to ameliorate the existing design of implant supported finger prosthesis. Distal phalange of middle finger replaced with implant supported silicone finger prosthesis is modified by utilizing a metal framework to support silicone material to improve rigidity while working. We could achieve a good function, esthetics and tactile sensibility with this modified design. Whenever, feasible this design can improve the performance and patients feel a deep sense of satisfaction and improved self-esteem with this modified prosthesis.

Toward a comprehensive hybrid physical-virtual reality simulator of peripheral anesthesia with ultrasound and neurostimulator guidance.

Science.gov (United States)

Samosky, Joseph T; Allen, Pete; Boronyak, Steve; Branstetter, Barton; Hein, Steven; Juhas, Mark; Nelson, Douglas A; Orebaugh, Steven; Pinto, Rohan; Smelko, Adam; Thompson, Mitch; Weaver, Robert A

2011-01-01

We are developing a simulator of peripheral nerve block utilizing a mixed-reality approach: the combination of a physical model, an MRI-derived virtual model, mechatronics and spatial tracking. Our design uses tangible (physical) interfaces to simulate surface anatomy, haptic feedback during needle insertion, mechatronic display of muscle twitch corresponding to the specific nerve stimulated, and visual and haptic feedback for the injection syringe. The twitch response is calculated incorporating the sensed output of a real neurostimulator. The virtual model is isomorphic with the physical model and is derived from segmented MRI data. This model provides the subsurface anatomy and, combined with electromagnetic tracking of a sham ultrasound probe and a standard nerve block needle, supports simulated ultrasound display and measurement of needle location and proximity to nerves and vessels. The needle tracking and virtual model also support objective performance metrics of needle targeting technique.

Malignant esophageal stenosis: treatment with the Wallsten ''TM prosthesis

International Nuclear Information System (INIS)

Paul, L.; Pinto, I.

1998-01-01

To discuss the technical aspects and adders the clinical results of treatment of malignant esophaged dysphagia by placement of a Wallstent prosthesis under fluoroscopic guidance. Over the past six years, we have implanted 63 Wallstent metallic prostheses in 40 patients with un operable malignant dysphagia of esophaged origin. The consisted of 36 men and 6 women with a mean age of 72 years. Seven of the neoplasms were associated with fistula.Six involved recurrent tumors at the point of the surgical anastomosis. Following implantation, the patients were evaluated clinically and radiologically at postoperative hour 48 and periodically thereafter until their death or until the study was completed in September 1996. The placement of the prostheses was achieved in all the patients. Immediate technical problems (malposition or failure to expand) in 27.5% of cases. Forty percent of the patients complained of plain, and there was one death due to massive hematemesis. A clear improvement in dysphagia was obtained was obtained in 79% of and only one of the 7 fistulas was closed. During follow-up, the main complication was obstruction of prosthesis (25%) as a result of tumor overgrowth (9 episodes in 8 patients) or due to food impaction (4 episodes in 3 patients). The rate of retreatment was 27.5%. The mean survival time after prosthesis implantation was 132 ±207 days and 62.5% of the devices were still permeable when the patient died. Implantation of Wallstent prosthesis in cases of malignant esophageal stenosis is easy and safe, and constitutes an effective treatment of dysphagia. Nevertheless, thorough knowledge of the technical aspects ensures better results and the strict assessment of the indications guarantees an improved cost-benefit ratio for this technique. (Author) 23 refs

Iris reconstruction using artificial iris prosthesis for management of aniridia.

Science.gov (United States)

Mostafa, Yehia S; Osman, Amr A; Hassanein, Dina H; Zeid, Ashraf M; Sherif, Ahmed M

2018-01-01

To discuss the limitations and benefits of the BrightOcular prosthetic artificial iris device in management of aniridia associated with aphakia or cataract. This is a retrospective study including 5 eyes of 4 patients who underwent implantation of the BrightOcular iris prosthesis (Stellar Devices) for total or partial aniridia. The cases included 2 eyes of 1 patient with congenital aniridia associated with congenital cataract and 3 eyes with traumatic aniridia: 1 with subluxated cataractous lens and 2 with aphakia. In all cases, the iris prosthesis was implanted after a 3-piece acrylic intraocular lens was implanted. We evaluated the clinical course with a minimum follow-up period of 6 months, the intraoperative and postoperative complications, and the cosmetic satisfaction of patients. All patients had improved uncorrected distance visual acuity and best-corrected distance visual acuity. All patients had a transient corneal edema that resolved within the first postoperative week. Only the patient with congenital aniridia had a permanent increase in intraocular pressure and developed a band keratopathy throughout a 2-year follow-up period. The prosthesis was well-centered in all eyes except for one case that required scleral suture fixation after 3 months. All patients had a satisfactory cosmetic appearance. BrightOcular iris prosthesis is a safe and useful tool to correct aniridia associated with pseudophakia or aphakia. Being foldable, it is easy to be implanted through a small incision and placed in the ciliary sulcus without sutures when properly sized. Cosmetic results are satisfactory. Sizing methods should be improved.

Early postoperative dislocation of the anterior Maverick lumbar disc prosthesis: report of 2 cases.

Science.gov (United States)

Gragnaniello, Cristian; Seex, Kevin A; Eisermann, Lukas G; Claydon, Matthew H; Malham, Gregory M

2013-08-01

The authors report on 2 cases of anterior dislocation of the Maverick lumbar disc prosthesis, both occurring in the early postoperative period. These cases developed after experience with more than 50 uneventful cases and were therefore thought to be unrelated to the surgeon's learning curve. No similar complications have been previously reported. The anterior Maverick device has a ball-and-socket design made of cobalt-chromium-molybdenum metal plates covered with hydroxyapatite. The superior and inferior endplates have keels to resist translation forces. The patient in Case 1 was a 52-year-old man with severe L4-5 discogenic pain; and in Case 2, a 42-year-old woman with disabling L4-5 and L5-S1 discogenic back pain. Both patients were without medical comorbidities and were nonsmokers with no risk factors for osteoporosis. Both had undergone uneventful retroperitoneal approaches performed by a vascular access surgeon. Computed tomography studies on postoperative Day 2 confirmed excellent prosthesis placement. Initial recoveries were uneventful. Two weeks postoperatively, after stretching (extension or hyperextension) in bed at home, each patient suffered the sudden onset of severe abdominal pain with anterior dislocation of the Maverick prosthesis. The patients were returned to the operating room and underwent surgery performed by the same spinal and vascular surgeons. Removal of the Maverick prosthesis and anterior interbody fusion with a separate cage and plate were performed. Both patients had recovered well with good clinical and radiological recovery at the 6- and 12-month follow-ups. Possible causes of the anterior dislocation of the Maverick prosthesis include the following: 1) surgeon error: In both cases the keel cuts were neat, and early postoperative CT confirmed good placement of the prosthesis; 2) equipment problem: The keel cuts may have been too large because the cutters were worn, which led to an inadequate press fit of the implants; 3) prosthesis

Case Report: Magnetically retained silicone facial prosthesis ...

African Journals Online (AJOL)

Prosthetic camouflaging of facial defects and use of silicone maxillofacial material are the alternatives to the surgical retreatment. Silicone elastomers provide more options to clinician for customization of the facial prosthesis which is simple, esthetically good when coupled with bio magnets for retention. Key words: Magnet ...

Fusion around cervical disc prosthesis: case report.

NARCIS (Netherlands)

Bartels, R.H.M.A.; Donk, R.

2005-01-01

OBJECTIVE AND IMPORTANCE: Cervical arthroplasty is a relatively new method to maintain motion after cervical anterior discectomy. Two cases are presented in which bony fusion occurred around a cervical disc prosthesis. CLINICAL PRESENTATION: A 30-year-old man and a 49-year-old woman underwent a

Heterotopic ossification associated with myelopathy following cervical disc prosthesis implantation.

Science.gov (United States)

Wenger, Markus; Markwalder, Thomas-Marc

2016-04-01

This case report presents a 37-year-old man with clinical signs of myelopathy almost 9 years after implantation of a Bryan disc prosthesis (Medtronic Sofamor Danek, Memphis, TN, USA) for C5/C6 soft disc herniation. As demonstrated on MRI and CT scan, spinal cord compression was caused by bony spurs due to heterotopic ossification posterior to the still moving prosthesis. The device, as well as the ectopic bone deposits, had to be removed because of myelopathy and its imminent aggravation. Conversion to anterior spondylodesis was performed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Short-Term Effect of Prosthesis Transforming Sensory Modalities on Walking in Stroke Patients with Hemiparesis

Science.gov (United States)

Sekiguchi, Yusuke; Honda, Keita; Ishiguro, Akio

2016-01-01

Sensory impairments caused by neurological or physical disorders hamper kinesthesia, making rehabilitation difficult. In order to overcome this problem, we proposed and developed a novel biofeedback prosthesis called Auditory Foot for transforming sensory modalities, in which the sensor prosthesis transforms plantar sensations to auditory feedback signals. This study investigated the short-term effect of the auditory feedback prosthesis on walking in stroke patients with hemiparesis. To evaluate the effect, we compared four conditions of auditory feedback from plantar sensors at the heel and fifth metatarsal. We found significant differences in the maximum hip extension angle and ankle plantar flexor moment on the affected side during the stance phase, between conditions with and without auditory feedback signals. These results indicate that our sensory prosthesis could enhance walking performance in stroke patients with hemiparesis, resulting in effective short-term rehabilitation. PMID:27547456

A kinematic assessment of knee prosthesis from fluoroscopy images

International Nuclear Information System (INIS)

Hossain, Mohammad Abrar; Fukunaga, Michihiko; Hirokawa, Shunji

2008-01-01

We have developed a technique for estimation 3D motion of knee prosthesis from its 2D perspective projections. Our estimation algorithm includes some innovations such as a two-step estimation algorithm, incorporative use of a geometric articulation model and a new method to solve two silhouettes' overlapping problem. Computer model simulations and experiments results demonstrated that our algorithms give sufficient accuracy. Next, with the cooperation of medical surgeons, we assessed the algorithm's clinical performance by applying it to moving fluoroscopy images of patients who had just undergone total knee arthroplasty (TKA) recently. Our experiments were done in four steps; first we have taken the moving X-ray pictures called fluoroscopy images of the knee prosthesis at different knee motions; second, introduced the absolute positions/orientations for both components, third, introduced the relative positions/orientations between the femoral and the tibial components and finally, introduced the contact points trajectories between the femur and the tibial insert. We drew the estimation results graphically and made the computer-aided detection (CAD) model pictures of the prosthesis, thereby helping us to assess how the relative motions between the femoral and the tibial components were generated. Estimation results of the clinical applications demonstrated that our algorithm worked well as like as theoretical. (author)

A new prosthetic alignment device to read and record prosthesis alignment data.

Science.gov (United States)

Pirouzi, Gholamhossein; Abu Osman, Noor Azuan; Ali, Sadeeq; Davoodi Makinejad, Majid

2017-12-01

Prosthetic alignment is an essential process to rehabilitate patients with amputations. This study presents, for the first time, an invented device to read and record prosthesis alignment data. The digital device consists of seven main parts: the trigger, internal shaft, shell, sensor adjustment button, digital display, sliding shell, and tip. The alignment data were read and recorded by the user or a computer to replicate prosthesis adjustment for future use or examine the sequence of changes in alignment and its effect on the posture of the patient. Alignment data were recorded at the anterior/posterior and medial/lateral positions for five patients. Results show the high level of confidence to record alignment data and replicate adjustments. Therefore, the device helps patients readjust their prosthesis by themselves, or prosthetists to perform adjustment for patients and analyze the effects of malalignment.

Endoscopic palliation of esophageal and cardial cancer: Nd:YAG laser and prosthesis

Science.gov (United States)

Norberto, Lorenzo; Ranzato, Riccardo; Marino, Saverio; Angriman, Imerio; Vella, Vincenzo; Donadi, Michele; D'Amico, D. F.

1997-12-01

From November 1, 1992 to January 31, 1997, 227 patients with inoperable esophageal and cardial carcinomas were treated with Nd:YAG laser therapy and prosthesis intubation. The retrograde technique was used in most cases. The tumor involved in 75 pts the Cardia, in 65 the middle thoracic esophagus, in 47 pts the lower thoracic esophagus, in 23 in the upper thoracic esophagus and in 17 in the cervical esophagus. The indications for palliative Nd:YAG laser and prosthesis intubation were a locally advanced or metastatic tumor in 146 pts (64.4%) and poor surgical risk in 81 pts (35.6%). The quality of palliation was evaluated according to the ability to swallow. The mean survival rate of the patients during the follow up was 22 weeks for the laser therapy and 16 weeks for the prosthesis intubation.

The influence of prosthesis diameter in stapes surgery: a meta-analysis and systematic review of the literature.

Science.gov (United States)

Laske, Roman D; Röösli, Christof; Chatzimichalis, Michail Vasileios; Sim, Jae Hoon; Huber, Alexander M

2011-06-01

To analyze the influence of stapes prosthesis diameter on postoperative hearing results after stapedotomy without interposition in otosclerotic patients. PubMed search from 1970 to 2009 using the key words stapedotomy or stapedectomy or otosclerosis or stapesplasty. Inclusion criteria to select articles and patient groups for meta-analysis and statistical analyses were as follows: otosclerosis as diagnosis, clear description of technique and prosthesis size, calibrated stapedotomy, and complete report of functional results. Five controlled studies were found analyzing the influence of prosthesis diameter and reporting the results in a comparable way for meta-analysis (n = 590). Sixty-two studies not analyzing the influence of prosthesis diameter contained comparable subgroups with a total of 9,536 cases. These cases were pooled according to their diameter (0.3, 0.4, 0.5, 0.6,and 0.8 mm). The results of air conduction, bone conduction, air-bone gap (ABG), and success rate (closure of the ABG within 10 dB as percentage of the total cases) for all groups and frequency-specific ABG results were gathered. Furthermore, 12 clinical and experimental studies were reviewed that did not contribute to the statistical analysis. A meta-analysis performed for success rate of the 5 controlled studies showed favorable results for 0.6-mm over 0.4-mm prostheses (success rate, 67% versus 58%, p = 0.05). In the statistical analysis of the pooled data, the 0.6-mm prosthesis showed better results compared with 0.4 mm (p prosthesis in the high frequencies. There was no difference in postoperative change of bone conduction in the 0.6- and 0.4-mm groups. Statistically significant results could not be assessed for other prosthesis diameters because of the small number of cases reported. A 0.6-mm diameter piston prosthesis is associated with significantly better results than a 0.4-mm prosthesis and should be used if the surgical conditions allow it.

Phantom studies of triple photon absorptiometry and bone mineral measurement at a hip prosthesis

International Nuclear Information System (INIS)

Farrell, T.J.; Webber, C.E.

1992-01-01

The feasibility of using triple photon absorptiometry (TPA) for the measurement of bone mineral mass about a hip prosthesis was examined. A theoretical expression describing the variance of TPA measurements was verified using a triple photon source and phantom materials which simulate the soft tissue-bone mineral-metal prosthesis system. The expression for the variance was used to determine an optimized set of photon energies. It was shown that a precision of 3% could be obtained for reasonable measurement times using this optimized set of energies and that TPA should be a feasible approach for measurement of bone mineral about a hip prosthesis. (orig.)

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metallic cemented or... Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis is a device intended to be implanted...

[COMPUTER ASSISTED DESIGN AND ELECTRON BEAMMELTING RAPID PROTOTYPING METAL THREE-DIMENSIONAL PRINTING TECHNOLOGY FOR PREPARATION OF INDIVIDUALIZED FEMORAL PROSTHESIS].

Science.gov (United States)

Liu, Hongwei; Weng, Yiping; Zhang, Yunkun; Xu, Nanwei; Tong, Jing; Wang, Caimei

2015-09-01

To study the feasibility of preparation of the individualized femoral prosthesis through computer assisted design and electron beammelting rapid prototyping (EBM-RP) metal three-dimensional (3D) printing technology. One adult male left femur specimen was used for scanning with 64-slice spiral CT; tomographic image data were imported into Mimics15.0 software to reconstruct femoral 3D model, then the 3D model of individualized femoral prosthesis was designed through UG8.0 software. Finally the 3D model data were imported into EBM-RP metal 3D printer to print the individualized sleeve. According to the 3D model of individualized prosthesis, customized sleeve was successfully prepared through the EBM-RP metal 3D printing technology, assembled with the standard handle component of SR modular femoral prosthesis to make the individualized femoral prosthesis. Customized femoral prosthesis accurately matching with metaphyseal cavity can be designed through the thin slice CT scanning and computer assisted design technology. Titanium alloy personalized prosthesis with complex 3D shape, pore surface, and good matching with metaphyseal cavity can be manufactured by the technology of EBM-RP metal 3D printing, and the technology has convenient, rapid, and accurate advantages.

Novel use of an air-filled breast prosthesis to allow radiotherapy to recurrent colonic cancer.

LENUS (Irish Health Repository)

O'Duffy, F

2012-02-01

AiM: The authors present the novel and successful use of an air-filled breast prosthesis for extra pelvic exclusion of small bowel to facilitate adjuvant radiotherapy following resection of recurrent adenocarcinoma of the ascending bowel. The therapeutic use of radiotherapy in colon cancer can cause acute or chronic radiation enteropathy. Mobile small bowel can be sequestered in \\'dead space\\' or by adhesions exposing it to adjuvant radiotherapy. A variety of pelvic partitioning methods have been described to exclude bowel from radiation fields using both native and prosthetic materials. METHOD: In this case a 68 year old presented with ascending colon adenocarcinoma invading the peritoneum and underwent en bloc peritoneal resection. Thirty-seven months later surveillance CT identified a local recurrence. Subsequent resection resulted in a large iliacus muscle defect which would sequester small bowel loops thus exposing the patient to radiation enteropathy. The lateral position of the defect precluded the use of traditional pelvic partitioning methods which would be unlikely to remain in place long enough to allow radiotherapy. A lightweight air-filled breast prosthesis (Allergan 133 FV 750 cms) secured in place with an omentoplasty was used to fill the defect. RESULTS: Following well tolerated radiotherapy the prosthesis was deflated under ultrasound guidance and removed via a 7-cm transverse incision above the right iliac crest. The patient is disease free 18 months later with no evidence of treatment related morbidity. CONCLUSION: The use of a malleable air-filled prosthesis for pelvic partitioning allows specific tailoring of the prosthesis size and shape for individual patient defects. It is also lightweight enough to be secured in place using an omentoplasty to prevent movement related prosthesis migration. In the absence of adequate omentum a mesh sling may be considered to allow fixation. In this case the anatomy of the prosthesis position allowed for its

Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

National Research Council Canada - National Science Library

Humayun, M

2001-01-01

An electronic retinal prosthesis is under development to treat retinitis pigmentosa and age-related macular degeneration, two presently incurable diseases of the outer retina that afflict millions world-wide...

Biomedical and psychosocial factors influencing transtibial prosthesis fit : a Delphi survey among health care professionals

NARCIS (Netherlands)

Baars, Erwin C.; Schrier, Ernst; Geertzen, Jan H.; Dijkstra, Pieter U.

2015-01-01

Purpose: We aimed to reach consensus among professionals caring for prosthesis users, on definitions of biomedical and psychosocial factors, to assess their influence on fit of transtibial prosthesis and to identify new factors. Method: A three-round, internet-based, Delphi survey was conducted

An innovative and simple approach to fabricate a hollow ocular prosthesis with functional lubricant reservoir: A solution to artificial eye comfort

Directory of Open Access Journals (Sweden)

Aditya Anil Kavlekar

2017-01-01

Full Text Available The loss of an eye is an emotional and psychological setback to the patient. An ocular prosthesis is created to restore the lost anatomical structure and to correct the cosmetic defect. The tear reflexes do not function at optimal levels in anophthalmic sockets which make prosthesis wear uncomfortable. This case report presents an innovative hollow ocular prosthesis with functional lubricant reservoir which upon normal blinking would draw the lubricant from the reservoir through an exit hole which spreads over the prosthesis allowing a comfortable and long duration of prosthesis wear.

Ipsilateral Fracture Shaft Femur with Neglected Dislocation of Prosthesis: A Case Report

Directory of Open Access Journals (Sweden)

Mantu Jain

2013-10-01

Full Text Available Introduction: Neglected hip dislocation is rare in today’s world and after prosthesis replacement even rarer finding. However such patients may not report to surgeons until they develop secondary complications. Management of such patient’s is a challenge to the treating surgeon and need to be tailored suiting to patient’s demands, expectations and constraints of financial resources. We did not find a similar case in the electronic and print media and therefore report this case which was innovatively managed. Case Report: A 60 year farmer presented with fracture shaft femur and ipsilateral dislocation prosthesis of right hip. He had a hemiarthroplasty done for fracture neck of femur in the past but used to walk with a lurch since he started to ambulate after discharge. However he was satisfied despite “some problems” which had caused shortening of his limb. The patient was informed of the various treatment options and their possible complications. He expressed his inability to afford a Total Hip Arthroplasty (THA at any stage and consented for other options discussed with him. The patient was positioned supine and adductor tenotomy done. Next he was positioned laterally and the fracture was fixed with heavy duty broad dynamic compression plate and screws. The wound was temporarily closed. Now through the previous scar via posterior approach the hip was exposed. The prosthesis was found to be firmly fixed to the proximal femur. The acetabulum was cleared with fibrous tissue. All attempts the prosthesis to relocate the prosthesis failed after several attempts and it was best decided to leave alone. Post operatively period was uneventful. At follow up he refused for any further manoeuvre in future inform of heavy traction and attempts to reduce the same. At one year when he was walking unaided and his X-rays showed that fracture had well united his SF-36 score was PCS – 49.6 and MCS – 51.9. Conclusion: Ipsilateral shaft femur fracture

Bicentric bipolar hip prosthesis: A radiological study of movement at the interprosthetic joint

Directory of Open Access Journals (Sweden)

Anil Kumar Rai

2011-01-01

Full Text Available Background: The bipolar hip prostheses after some time functions as a unipolar device. There is a need to change the design of bipolar hip prostheses to make it function as a bipolar device over a prolonged period of time. A bicentric bipolar hip prosthesis was used as an implant for various conditions of the hip. We evaluated the movement of this newly developed prosthesis at the interprosthetic joint radiologically at periodic intervals. Materials and Methods: Fifty two cases were operarted with the Bicentric bipolar prosthesis for indications like fracture neck of femur and various other diseases of the hip and were followed up with serial radiographs at periodic intervals to evaluate, what fraction of the total abduction at the hip was occurring at the interprosthetic joint. Results: In cases of intracapsular fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 33.74% (mean value of all the patients, which fell to 25.66% at 1.5 years. In indications for bipolar hemireplacement other than fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 71.71% (mean value and at 1.5 years it was 67.52%. Conclusion: This study shows the relative preservation of inner bearing movement in the bipolar hip prosthesis with time probably due its refined design. Further refinements are needed to make the prosthesis work better in patients of intracapsular fracture neck femur.

Characterization of a Polymer-Based, Fully Organic Prosthesis for Implantation into the Subretinal Space of the Rat.

Science.gov (United States)

Antognazza, Maria Rosa; Di Paolo, Mattia; Ghezzi, Diego; Mete, Maurizio; Di Marco, Stefano; Maya-Vetencourt, José Fernando; Maccarone, Rita; Desii, Andrea; Di Fonzo, Fabio; Bramini, Mattia; Russo, Angela; Laudato, Lucia; Donelli, Ilaria; Cilli, Michele; Freddi, Giuliano; Pertile, Grazia; Lanzani, Guglielmo; Bisti, Silvia; Benfenati, Fabio

2016-09-01

Replacement strategies arise as promising approaches in case of inherited retinal dystrophies leading to blindness. A fully organic retinal prosthesis made of conjugated polymers layered onto a silk fibroin substrate is engineered. First, the biophysical and surface properties are characterized; then, the long-term biocompatibility is assessed after implantation of the organic device in the subretinal space of 3-months-old rats for a period of five months. The results indicate a good stability of the subretinal implants over time, with preservation of the physical properties of the polymeric layer and a tight contact with the outer retina. Immunoinflammatory markers detect only a modest tissue reaction to the surgical insult and the foreign body that peaks shortly after surgery and progressively decreases with time to normal levels at five months after implantation. Importantly, the integrity of the polymeric layer in direct contact with the retinal tissue is preserved after five months of implantation. The recovery of the foreign-body tissue reaction is also associated with a normal b-wave in the electroretinographic response. The results demonstrate that the device implanted in nondystrophic eyes is well tolerated, highly biocompatible, and suitable as retinal prosthesis in case of photoreceptor degeneration. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evidence of echoic memory with a multichannel cochlear prosthesis.

Science.gov (United States)

Jerger, S; Watkins, M J

1988-10-01

Short-term memory was examined in a subject with a multichannel cochlear prosthesis. Serial recall for lists of digits revealed what are widely regarded as the principal hallmarks of echoic memory, namely the recency effect and the suffix effect. Thus, probability of recall increased for the last one or two digits, except when a nominally irrelevant but spoken item was appended to the to-be-remembered list. It appears, therefore, that a multichannel cochlear implant can give rise to not only the perception of, but also an echoic memory for, speech. As with normal subjects, the suffix effect did not occur with a nonspeech suffix, implying that the echoic memory from the prosthesis shows normal sensitivity to the distinction between speech and nonspeech.

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease

NARCIS (Netherlands)

van Slooten, Ymkje J.; Melle, van Joost P.; Freling, Hendrik G.; Bouma, Berto J.; van Dijk, Arie P. J.; Jongbloed, Monique R. M.; Post, Martijn C.; Sieswerda, Gertjan T.; in 't Veld, Anna Huis; Ebels, Tjark; Voors, Adriaan A.; Pieper, Petronella G.

Objectives To report the prevalence of aortic valve prosthesis patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease

NARCIS (Netherlands)

van Slooten, Ymkje J.; van Melle, Joost P.; Freling, Hendrik G.; Bouma, Berto J.; van Dijk, Arie Pj; Jongbloed, Monique Rm; Post, Martijn C.; Sieswerda, Gertjan T.; Huis In 't Veld, Anna; Ebels, Tjark; Voors, Adriaan A.; Pieper, Petronella G.

2016-01-01

To report the prevalence of aortic valve prosthesis-patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis later in

Prosthetic replacement of the medial meniscus in cadaveric knees - Does the prosthesis mimic the functional behavior of the native meniscus?

NARCIS (Netherlands)

Tienen, TG; Verdonschot, N; Heijkants, RGJC; Buma, R; Scholten, JGF; van Kampen, A; Veth, RPH

2004-01-01

Meniscus replacement by a polymer meniscus prosthesis in dogs resulted in generation of new meniscal tissue. Hypothesis: Optimal functioning of the prosthesis would involve realistic deformation and motion patterns of the prosthesis during knee joint motion. Study Design: Controlled laboratory

The Talar Body Prosthesis: Results at Ten to Thirty-six Years of Follow-up.

Science.gov (United States)

Harnroongroj, Thos; Harnroongroj, Thossart

2014-07-16

Satisfactory results of implantation of the talar body prosthesis were reported in 1997, although some complications associated with the initial design were noted. The present study evaluated outcomes of treatment with a modified talar body prosthesis. Of the thirty-six talar body prostheses implanted with use of a transmalleolar surgical approach from 1974 to 2011, thirty-three were available for follow-up at ten to thirty-six years or had failed prior to that time. The indication for implantation had been osteonecrosis in twenty-three patients, a comminuted talar fracture in eight, and a talar body tumor in two. Twenty-eight of the thirty-three prostheses were still in place at the time of final follow-up and five had failed prior to five years. The duration of follow-up was ten to twenty years in eight patients, twenty to thirty years in eleven, and thirty to thirty-six years in nine. The AOFAS (American Orthopaedic Foot & Ankle Society) ankle-hindfoot score did not differ significantly among these three groups. Patients over sixty-five years of age with underlying disease that impeded walking ability had lower AOFAS scores. Early prosthesis failure occurred as a result of size mismatch in two patients, tumor recurrence in one, infection in one, and osteonecrosis of the talar head and neck in one. These failures, which occurred at eight to fifty-seven months, were treated with tibiotalar arthrodesis in three patients, prosthesis revision in one, and below-the-knee amputation in one. Although early prosthesis failure may occur, survival of the talar body prosthesis can provide satisfactory ankle and foot function. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Investigation of the in-vitro loading on an artificial spinal disk prosthesis

Energy Technology Data Exchange (ETDEWEB)

Kyriacou, P A; Pancholi, M P [School of Engineering and Mathematical Sciences, City University London (United Kingdom); Yeh, J, E-mail: P.Kyriacou@city.ac.u [Department of Neurosurgery, Royal London Hospital, Barts and the London NHS Trust, London (United Kingdom)

2009-07-01

Spinal diseases imposes considerable burden to both patients and society. In recent years, much surgical efforts have been made in advancing the treatment of neck and back pain. Of particular prominence is the increasing clinical acceptance and use of intervertebral artificial disk prosthesis for the treatment of discogenic back pain. Despite this increased use of such disks, their in-vivo monitoring remains rudimentary. In an effort to develop an intelligent artificial spinal disk where the in-vivo loading of the spine can by studied for the first time an experimental set up has been created in order to initially study the in-vitro loading on an artificial disc prosthesis. Eight strain gauges and two piezoresistive sensors were used and placed suitably in the artificial disk prosthesis. The results from the in-vitro loading showed linear relationship between loading and the outputs from the sensors with good repeatability and less hysteresis.

Investigation of the in-vitro loading on an artificial spinal disk prosthesis

International Nuclear Information System (INIS)

Kyriacou, P A; Pancholi, M P; Yeh, J

2009-01-01

Spinal diseases imposes considerable burden to both patients and society. In recent years, much surgical efforts have been made in advancing the treatment of neck and back pain. Of particular prominence is the increasing clinical acceptance and use of intervertebral artificial disk prosthesis for the treatment of discogenic back pain. Despite this increased use of such disks, their in-vivo monitoring remains rudimentary. In an effort to develop an intelligent artificial spinal disk where the in-vivo loading of the spine can by studied for the first time an experimental set up has been created in order to initially study the in-vitro loading on an artificial disc prosthesis. Eight strain gauges and two piezoresistive sensors were used and placed suitably in the artificial disk prosthesis. The results from the in-vitro loading showed linear relationship between loading and the outputs from the sensors with good repeatability and less hysteresis.

Design and Control of a New Biomimetic Transfemoral Knee Prosthesis Using an Echo-Control Scheme

Directory of Open Access Journals (Sweden)

Mario G. Bernal-Torres

2018-01-01

Full Text Available Passive knee prostheses require a significant amount of additional metabolic energy to carry out a gait cycle, therefore affecting the natural human walk performance. Current active knee prostheses are still limited because they do not reply with accuracy of the natural human knee movement, and the time response is relatively large. This paper presents the design and control of a new biomimetic-controlled transfemoral knee prosthesis based on a polycentric-type mechanism. The aim was to develop a knee prosthesis able to provide additional power and to mimic with accuracy of the natural human knee movement using a stable control strategy. The design of the knee mechanism was obtained from the body-guidance kinematics synthesis based on real human walking patterns obtained from computer vision and 3D reconstruction. A biomechanical evaluation of the synthesized prosthesis was then carried out. For the activation and control of the prosthesis, an echo-control strategy was proposed and developed. In this echo-control strategy, the sound side leg is sensed and synchronized with the activation of the knee prosthesis. An experimental prototype was built and evaluated in a test rig. The results revealed that the prosthetic knee is able to mimic the biomechanics of the human knee.

New protocol for construction of eyeglasses-supported provisional nasal prosthesis using CAD/CAM techniques.

Science.gov (United States)

Ciocca, Leonardo; Fantini, Massimiliano; De Crescenzio, Francesca; Persiani, Franco; Scotti, Roberto

2010-01-01

A new protocol for making an immediate provisional eyeglasses-supported nasal prosthesis is presented that uses laser scanning, computer-aided design/computer-aided manufacturing procedures, and rapid prototyping techniques, reducing time and costs while increasing the quality of the final product. With this protocol, the eyeglasses were digitized, and the relative position of the nasal prosthesis was planned and evaluated in a virtual environment without any try-in appointment. This innovative method saves time, reduces costs, and restores the patient's aesthetic appearance after a disfiguration caused by ablation of the nasal pyramid better than conventional restoration methods. Moreover, the digital model of the designed nasal epithesis can be used to develop a definitive prosthesis anchored to osseointegrated craniofacial implants.

Sexual Function and Quality of Life Before and After Penile Prosthesis Implantation Following Radial Forearm Flap Phalloplasty.

Science.gov (United States)

Young, Ezekiel E; Friedlander, Daniel; Lue, Kathy; Anele, Uzoma A; Khurgin, Jacob L; Bivalacqua, Trinity J; Burnett, Arthur L; Redett, Richard J; Gearhart, John P

2017-06-01

To provide sexual function and quality of life outcomes in patients with severe penile deficiency who underwent radial forearm flap phalloplasty with and without penile prosthesis implantation. Patients with history of severe penile deficiency who underwent microsurgical radial forearm flap phalloplasty with and without penile prosthesis implantation between 2007 and 2014 were identified. They completed a set of web-based validated questionnaires including the International Index of Erectile Function, the Pediatric Penile Perception Score, the Sexual Quality of Life for Men, and several items addressing general quality of life. Outcomes were compared between groups. Nine of the 12 identified patients who had prosthesis after phalloplasty and 4 out of the 7 phalloplasty-only patients completed the survey, resulting in an overall response rate of 68%. Among the phalloplasty-prosthesis patients, 66% reported current sexual activity and 78% reported regular masturbation, whereas 1 of the 4 phalloplasty-only patients reported both. Prosthesis patients scored notably higher in all domains of the International Index of Erectile Function except for sexual desire. In contrast, they demonstrated similar scores of penile perception, as well as general and sexual quality of life. Among patients who have undergone flap phalloplasty, the subsequent placement of penile prosthesis appears to effectively allow for both intercourse and masturbation, resulting in measurable improvements in orgasmic function, intercourse satisfaction, and overall sexual satisfaction. Despite these important benefits, prosthesis placement does not appear to result in improvements in penile perception scores, or general or sexual quality of life. Copyright © 2017 Elsevier Inc. All rights reserved.

Early results of patellofemoral inlay resurfacing arthroplasty using the HemiCap Wave prosthesis.

Science.gov (United States)

Patel, Akash; Haider, Zakir; Anand, Amarjit; Spicer, Dominic

2017-01-01

Common surgical treatment options for isolated patellofemoral osteoarthritis include arthroscopic procedures, total knee replacement and patellofemoral replacement. The HemiCap Wave patellofemoral resurfacing prosthesis is a novel inlay design introduced in 2009 with scarce published data on its functional outcomes. We aim to prospectively evaluate early functional outcomes and complications, for patients undergoing a novel inlay resurfacing arthroplasty for isolated patellofemoral arthrosis in an independent centre. From 2010 to 2013, 16 consecutive patients underwent patellofemoral resurfacing procedures using HemiCap Wave (Arthrosurface Inc., Franklin, Massachusetts, USA) for anterior knee pain with confirmed radiologically and/or arthroscopically isolated severe patellofemoral arthrosis. Standardized surgical technique, as recommended by the implant manufacturer, was followed. Outcome measures included range of movement, functional knee scores (Oxford Knee Score (OKS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Short Form-36 (SF-36)), radiographic disease progression, revision rates and complications. Eight men and eight women underwent patellofemoral HemiCap Wave resurfacing, with an average age of 63 years (range: 46-83). Average follow-up was 24.1 months (6-34). Overall, post-operative scores were excellent. There was a statistically significant improvement in the post-operative OKS, KOOS and SF-36 scores ( p patellofemoral resurfacing prosthesis has excellent early results in terms of functional outcomes, radiological outcomes and low complication rates. At the very least, early results show that the HemiCap Wave is comparable to more established onlay prostheses. The HemiCap Wave thus provides a safe and effective surgical option in the treatment of isolated patellofemoral osteoarthritis in selected patients.

Natural Marine and Synthetic Xenobiotics Get on Nematode's Nerves: Neuro-Stimulating and Neurotoxic Findings in Caenorhabditis elegans.

Science.gov (United States)

Lieke, Thora; Steinberg, Christian E W; Ju, Jingjuan; Saul, Nadine

2015-05-06

Marine algae release a plethora of organic halogenated compounds, many of them with unknown ecological impact if environmentally realistic concentrations are applied. One major compound is dibromoacetic acid (DBAA) which was tested for neurotoxicity in the invertebrate model organism Caenorhabditis elegans (C. elegans). This natural compound was compared with the widespread synthetic xenobiotic tetrabromobisphenol-A (TBBP-A) found in marine sediments and mussels. We found a neuro-stimulating effect for DBAA; this is contradictory to existing toxicological reports of mammals that applied comparatively high dosages. For TBBP-A, we found a hormetic concentration-effect relationship. As chemicals rarely occur isolated in the environment, a combination of both organobromines was also examined. Surprisingly, the presence of DBAA increased the toxicity of TBBP-A. Our results demonstrated that organohalogens have the potential to affect single organisms especially by altering the neurological processes, even with promoting effects on exposed organisms.

Complications and Clinical Considerations of the Implant-Retained Zirconia Complete-Arch Prosthesis with Various Opposing Dentitions.

Science.gov (United States)

Gonzalez, Jorge; Triplett, Robert G

To evaluate the performance of the implant-retained zirconia complete-arch prosthesis with various opposing dentitions. The 40 patients included in this retrospective case series study were treated with one or two implant-retained zirconia complete-arch prostheses (ZIRCAP) using the Zirkonzahn protocol. Prettau zirconia frames were created with strategic cutbacks in the structure to extend zirconia incisal coverage of the esthetic anterior sextants and complete monolithic zirconia in the molar areas; subsequent layers of porcelain were applied to nonfunctional and esthetic areas. Patients had three possible occlusal scenarios: (1) maxillary ZIRCAP and mandibular ZIRCAP, (2) maxillary ZIRCAP and mandibular natural dentition, and (3) maxillary ZIRCAP and mandibular conventional hybrid prosthesis. Complications were recorded during follow-up appointments 3, 6, and 12 months after definitive prosthesis delivery. The mean treatment observation period was 33 months. Eight prosthetic complications were noted for the 40 implant-retained zirconia complete-arch prostheses (18.18%), including six cases of minor porcelain chipping and two cases of debonding of the metal insert from the zirconia framework. Maxillary ZIRCAP opposing mandibular ZIRCAP and maxillary ZIRCAP opposing mandibular natural dentition occlusal scenarios presented the same complication ratio of 4. No complications were seen in the maxillary ZIRCAP opposing mandibular conventional hybrid prosthesis group, yet 16 complications were found as denture tooth fractures in 12 mandibular conventional hybrid prostheses (ratio of 0.75). The results indicate that the implant-retained zirconia complete-arch prosthesis offers acceptable performance for use as an alternative to the conventional titanium framework acrylic veneer prosthesis for complete edentulism with a lower incidence of prosthetic complications and fewer maintenance appointments. Chipping of veneering porcelain was the most common complication, but a

Prosthesis-patient mismatch

Directory of Open Access Journals (Sweden)

Philippe Pibarot

2011-04-01

Full Text Available Prosthesis-patient mismatch (PPM is present when the effective orifice area of the inserted prosthetic valve is too small in relation to body size. Its main hemodynamic consequence is to generate higher than expected gradients through normally functioning prosthetic valves. The purpose of this review is to present an update on the present state of knowledge with regards to diagnosis, prognosis and prevention of PPM. PPM is a frequent occurrence (20%–70% of aortic valve replacements that has been shown to be associated with worse hemodynamics, less regression of left ventricular hypertrophy, more cardiac events, and lower survival. Moreover, as opposed to most other risk factors, PPM can largely be prevented by using a prospective strategy at the time of operation.

Bioelectronic retinal prosthesis

Science.gov (United States)

Weiland, James D.

2016-05-01

Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

Numerical analysis of an osseointegrated prosthesis fixation with reduced bone failure risk and periprosthetic bone loss

NARCIS (Netherlands)

Tomaszewski, P. M.; van Diest, M.; Bulstra, S. K.; Verdonschot, N.; Verkerke, G. J.

2012-01-01

Currently available implants for direct attachment of prosthesis to the skeletal system after transfemoral amputation (OPRA system. Integrum AB, Sweden and ISP Endo/Exo prosthesis, ESKA Implants AG, Germany) show many advantages over the conventional socket fixation. However, restraining

THR Simulator – the software for generating radiographs of THR prosthesis

Directory of Open Access Journals (Sweden)

Hou Sheng-Mou

2009-01-01

Full Text Available Abstract Background Measuring the orientation of acetabular cup after total hip arthroplasty is important for prognosis. The verification of these measurement methods will be easier and more feasible if we can synthesize prosthesis radiographs in each simulated condition. One reported method used an expensive mechanical device with an indeterminable precision. We thus develop a program, THR Simulator, to directly synthesize digital radiographs of prostheses for further analysis. Under Windows platform and using Borland C++ Builder programming tool, we developed the THR Simulator. We first built a mathematical model of acetabulum and femoral head. The data of the real dimension of prosthesis was adopted to generate the radiograph of hip prosthesis. Then with the ray tracing algorithm, we calculated the thickness each X-ray beam passed, and then transformed to grey scale by mapping function which was derived by fitting the exponential function from the phantom image. Finally we could generate a simulated radiograph for further analysis. Results Using THR Simulator, the users can incorporate many parameters together for radiograph synthesis. These parameters include thickness, film size, tube distance, film distance, anteversion, abduction, upper wear, medial wear, and posterior wear. These parameters are adequate for any radiographic measurement research. This THR Simulator has been used in two studies, and the errors are within 2° for anteversion and 0.2 mm for wearing measurement. Conclusion We design a program, THR Simulator that can synthesize prosthesis radiographs. Such a program can be applied in future studies for further analysis and validation of measurement of various parameters of pelvis after total hip arthroplasty.

Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

National Research Council Canada - National Science Library

Humayun, M

2001-01-01

.... Previous studies have established the feasibility of the retinal prosthesis. Short-term tests in blind humans have shown that degenerated retina will respond to light in a way that is consistent with form vision...

[Our experience with the use of Active-C cervical prosthesis].

Science.gov (United States)

Misik, Ferenc; Böösi, Martina; Papp, Zoltán; Padányi, Csaba; Banczerowski, Péter

2016-09-30

The most widely used surgical procedure in the treatment of cervical spine disc hernias have been the anterior cervical discectomy and fusion for decades. The usage of cervical disc prostheses enabled us to preserve the movements of the affected segments, hereby reducing the overexertion of the adjacent vertebrae and discs. Our goal is to follow our patients operated with Active-C prosthesis (which is used in the Institute since 2010) to gather information about the change of their complaints and about the functioning and unwanted negative effects of the prostheses. Question - Is the usage of Active-C prosthesis an efficient procedure? Between 2010 and 2013, performing the survey of neurological conditions and functional X-ray examinations. We measured the complaints of the patients using the Visual Analogue Scale, Neck Disability Index and Cervical Spine Outcomes Questionnaire. The control group consisted of patients who were operated in one segment using the fusion technique. In the study group according to the Neck Disability Index scale after 18 months, seven patients had no complaints, while twelve persons reported mild and the remaining six moderate complaints. In the control group, moderate complaints were present in four patients, while twelve patients reported mild complaints. The other eight persons showed no complaints. According to the results of the Visual Analogue Scale in the group of prosthesis, the degree of referred pain decreased from 8.6 to 1.84 one and a half years after the surgery. A decrease was observable in the case of axial pain too, from 6.6 down to 1.92 (pcervical disc prosthesis can be considered as an efficient procedure, but at the same time the advantages can only be determined in the long run, therefore further following and studies are required.

Functional property of the cardiac valve prosthesis evaluated in vivo by cine-radiography

International Nuclear Information System (INIS)

Murakoshi, Sadaaki

1986-01-01

Functional property of the convexo-concave Bjoerk-Shiley cardiac valve prosthesis implanted in the mitral position of 21 patients was investigated by integrated cine-radiography repeated for a long term after operation. The maximum opening angle of the tilting disc was 58 ± 2 deg, and was not affected by atrial fibrillation nor by tachycardia up to 160 bpm. There was no change in the maximum opening angle of the disc observed during follow-up period. Good correlation between shortning of the disc opening time and increase in pulse rate suggests excellent adaptation of this prosthesis for tachycardia induced by exercise or electric pacing. However, atrial fibrillation causes time delay in disc closure immediately after prolonged R-R interval. Disc rotation alleviating disc wear was observed in all the patients whether it moves slow or quick. Dysfunction of the disc opening can be readily determined not only by measuring the maximum disc opening angle, but also by observing the characteristic movement indicated in this study. It is concluded from these results that clinical apprication for the convexo-concave Bjoerk-Shiley valve prosthesis is appropriate and cine-radiography is an useful non-invasive examination of cardiac valve prosthesis for long follow-up period. (author)

Functional property of the cardiac valve prosthesis evaluated in vivo by cine-radiography

Energy Technology Data Exchange (ETDEWEB)

Murakoshi, Sadaaki

1986-07-01

Functional property of the convexo-concave Bjoerk-Shiley cardiac valve prosthesis implanted in the mitral position of 21 patients was investigated by integrated cine-radiography repeated for a long term after operation. The maximum opening angle of the tilting disc was 58 +- 2 deg, and was not affected by atrial fibrillation nor by tachycardia up to 160 bpm. There was no change in the maximum opening angle of the disc observed during follow-up period. Good correlation between shortning of the disc opening time and increase in pulse rate suggests excellent adaptation of this prosthesis for tachycardia induced by exercise or electric pacing. However, atrial fibrillation causes time delay in disc closure immediately after prolonged R-R interval. Disc rotation alleviating disc wear was observed in all the patients whether it moves slow or quick. Dysfunction of the disc opening can be readily determined not only by measuring the maximum disc opening angle, but also by observing the characteristic movement indicated in this study. It is concluded from these results that clinical apprication for the convexo-concave Bjoerk-Shiley valve prosthesis is appropriate and cine-radiography is an useful non-invasive examination of cardiac valve prosthesis for long follow-up period.

Evaluation of Gait Performance of a Hemipelvectomy Amputation Walking with a Canadian Prosthesis

Directory of Open Access Journals (Sweden)

M. T. Karimi

2014-01-01

Full Text Available Background. Hemipelvectomy amputation is a surgical procedure in which lower limb and a portion of pelvic are removed. There are a few studies in the literature regarding the performance of subjects with hip disarticulation during walking. However, there is no study on gait analysis of hemipelvectomy subject. Therefore, the aim of this paper was to evaluate the gait and stability of subject with hemipelvectomy amputation. Case Description and Methods. A subject with hemipelvectomy amputation at right side was involved in this study. He used a Canadian prosthesis with single axis ankle joint, 3R21 knee joint, and 7E7 hip joint for more than 10 years. The kinetic and kinematic parameters were collected by a motion analysis system and a Kistler force platform. Findings and Outcomes. There was a significant difference between knee, hip, and ankle range of motions and their moments in the sound and prosthesis sides. In the other side, the stability of the subject in the anteroposterior direction seems to be better than that in the mediolateral direction. Conclusions. There was a significant asymmetry between the kinetic and kinematic performance of the sound and prosthesis sides, which may be due to lack of muscular power and alignment of prosthesis components.

Research and development of a versatile portable speech prosthesis

Science.gov (United States)

1981-01-01

The Versatile Portable Speech Prosthesis (VPSP), a synthetic speech output communication aid for non-speaking people is described. It was intended initially for severely physically limited people with cerebral palsy who are in electric wheelchairs. Hence, it was designed to be placed on a wheelchair and powered from a wheelchair battery. It can easily be separated from the wheelchair. The VPSP is versatile because it is designed to accept any means of single switch, multiple switch, or keyboard control which physically limited people have the ability to use. It is portable because it is mounted on and can go with the electric wheelchair. It is a speech prosthesis, obviously, because it speaks with a synthetic voice for people unable to speak with their own voices. Both hardware and software are described.

Dextran/Albumin hydrogel sealant for Dacron(R) vascular prosthesis.

Science.gov (United States)

Lisman, Anna; Butruk, Beata; Wasiak, Iga; Ciach, Tomasz

2014-05-01

In this paper, the authors describe a novel type of hydrogel coating prepared from the copolymer of human serum albumin and oxidized dextran. The material was designed as a hydrogel sealant for polyester (Dacron®)-based vascular grafts. Dextran was chosen as a coating material due to its anti-thrombogenic properties. Prepared hydrogels were compared with similar, already known biomaterial made from gelatine with the same cross-linking agent. Obtained hydrogels, prepared from various ratios of oxidized dextran/albumin or oxidized dextran/gelatine, showed different cross-linking densities, which caused differences in swelling, degradation rate and mechanical properties. Permeability tests confirmed the complete tightness of the hydrogel-modified prosthesis. Results showed that application of the hydrogel coating provided leakage-free prosthesis and eliminated the need of pre-clotting.

21 CFR 888.3358 - Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal/polymer/metal semi-constrained... Devices § 888.3358 Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis. (a) Identification. A hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis is a device...

21 CFR 888.3390 - Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metal/polymer... § 888.3390 Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis is a two-part...

21 CFR 888.3380 - Hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) trunnion-bearing... Devices § 888.3380 Hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis is a two...

Prosthetic Rehabilitation of Mandibular Defects with Fixed-removable Partial Denture Prosthesis Using Precision Attachment: A Twin Case Report.

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Munot, Vimal Kantilal; Nayakar, Ramesh P; Patil, Raghunath

2017-01-01

The restoration of normal function and esthetic appearance with a dental prosthesis is a major challenge in the rehabilitation of patients who have lost their teeth and surrounding bone because of surgery for oral cyst or tumor. Rehabilitation with fixed or removable prosthesis is even more challenging when the edentulous span is long and the ridge is defective. Anatomic deformities and unfavorable biomechanics encountered in the region of resection add to the misery. In such situation, a fixed-removable prosthesis allows favorable biomechanical stress distribution along with restoration of esthetics, phonetics, comfort, hygiene, and better postoperative care and maintenance. This article describes rehabilitation of two cases with mandibular defects with an attachment-retained fixed-removable hybrid prosthesis.

The Influence of Artificial Cervical Disc Prosthesis Height on the Cervical Biomechanics: A Finite Element Study.

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Yuan, Wei; Zhang, Haiping; Zhou, Xiaoshu; Wu, Weidong; Zhu, Yue

2018-05-01

Artificial cervical disc replacement is expected to maintain normal cervical biomechanics. At present, the effect of the Prestige LP prosthesis height on cervical biomechanics has not been thoroughly studied. This finite element study of the cervical biomechanics aims to predict how the parameters, like range of motion (ROM), adjacent intradiscal pressure, facet joint force, and bone-implant interface stress, are affected by different heights of Prestige LP prostheses. The finite element model of intact cervical spine (C3-C7) was obtained from our previous study, and the model was altered to implant Prestige LP prostheses at the C5-C6 level. The effects of the height of 5, 6, and 7 mm prosthesis replacement on ROM, adjacent intradiscal pressure, facet joint force, as well as the distribution of bone-implant interface stress were examined. ROM, adjacent intradiscal pressure, and facet joint force increased with the prosthesis height, whereas ROM and facet joint force decreased at C5-C6. The maximal stress on the inferior surface of the prostheses was greater than that on the superior surface, and the stresses increased with the prosthesis height. The biomechanical changes were slightly affected by the height of 5 and 6 mm prostheses, but were strongly affected by the 7-mm prosthesis. An appropriate height of the Prestige LP prosthesis can preserve normal ROM, adjacent intradiscal pressure, and facet joint force. Prostheses with a height of ≥2 mm than normal can lead to marked changes in the cervical biomechanics and bone-implant interface stress. Copyright © 2018 Elsevier Inc. All rights reserved.

Finite element analysis of stresses in fixed prosthesis and cement layer using a three-dimensional model

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Arunachalam Sangeetha

2012-01-01

Full Text Available Context: To understand the effect of masticatory and parafunctional forces on the integrity of the prosthesis and the underlying cement layer. Aims: The purpose of this study was to evaluate the stress pattern in the cement layer and the fixed prosthesis, on subjecting a three-dimensional finite element model to simulated occlusal loading. Materials and Methods: Three-dimensional finite element model was simulated to replace missing mandibular first molar with second premolar and second molar as abutments. The model was subjected to a range of occlusal loads (20, 30, 40 MPa in two different directions - vertical and 30° to the vertical. The cements (zinc phosphate, polycarboxylate, glass ionomer, and composite were modeled with two cement thicknesses - 25 and 100 μm. Stresses were determined in certain reference points in fixed prosthesis and the cement layer. Statistical Analysis Used: The stress values are mathematic calculations without variance; hence, statistical analysis is not routinely required. Results: Stress levels were calculated according to Von Mises criteria for each node. Maximum stresses were recorded at the occlusal surface, axio-gingival corners, followed by axial wall. The stresses were greater with lateral load and with 100-μm cement thickness. Results revealed higher stresses for zinc phosphate cement, followed by composites. Conclusions: The thinner cement interfaces favor the success of the prosthesis. The stresses in the prosthesis suggest rounding of axio-gingival corners and a well-established finish line as important factors in maintaining the integrity of the prosthesis.

21 CFR 874.3695 - Mandibular implant facial prosthesis.

Science.gov (United States)

2010-04-01

... made of materials such as stainless steel, tantalum, titanium, cobalt-chromium based alloy... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mandibular implant facial prosthesis. 874.3695... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular implant...

Biomechanical conceptual design of a passive transfemoral prosthesis.

NARCIS (Netherlands)

Ünal, Ramazan; Carloni, Raffaella; Hekman, Edsko E.G.; Stramigioli, Stefano; Koopman, Hubertus F.J.M.

In this study, we present the conceptual design of a fully-passive transfemoral prosthesis. The proposed design is inspired by the analysis of the musculo-skeletal activity of the healthy human leg. In order to realize an energy efficient device, we introduce three storage elements, which are

Autoinflation Leading to Failure of Two-Piece Ambicor Implantable Penile Prosthesis: An Outcome from a Methodical Treatment of Recalcitrant Stuttering Priapism

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R. Charles Welliver

2014-01-01

Full Text Available Introduction. We present the case of a patient who received a two-piece Ambicor penile prosthesis for idiopathic recurrent “stuttering” priapism refractory to other treatment options. The patient returned unable to deflate the device due to an interesting anatomically induced mechanical failure. Aims. To describe the method and findings of this inflatable prosthesis failure. Results. Prosthesis failure occurred due to restrictive corporal diameter and the unique characteristics of fluid reservoir location in the two-piece inflatable prosthesis. The patient was successfully converted to a semirigid prosthesis with resolution of the pain that was due to his prosthesis autoinflation. Conclusion. Stuttering priapism remains a challenging clinical problem. Penile implantation is a reasonable long-term solution in a patient refractory to less invasive options. In patients with fibrotic corpora, a malleable device should be considered (at least temporarily if unable to dilate comfortably to 13 mm.

Effects of Prosthesis Stem Tapers on Stress Distribution of Cemented Hip Arthroplasty

International Nuclear Information System (INIS)

Abdullah, Abdul Halim; Nor, Mohd Asri Mohd; Saman, Alias Mohd; Tamin, Mohd Nasir; Kadir, Mohammed Rafiq Abdul

2010-01-01

Aseptic loosening effects are critical issues in encouraging long term stability of cemented hip arthroplasty. Stress shielding is believed to be an important factor that contributes to the aseptic loosening problems. The numerous changes in the prosthesis stem design are intended to minimize the stress shielding and aseptic loosening problems and to improve the long term performance of the implants. In this study, the stress distribution in cemented hip arthroplasty is established using finite element method. The taper of the prosthesis is designed to be 3 deg. at anterior/posterior, 3 deg. at medial/lateral and 10 deg. from wide lateral to narrow medial. Major muscle loads and contact forces are simulated for walking (toe-off phase) and stair climbing load cases. Effects of prosthesis stem tapers on the resulting stress distribution are investigated. Results show that compressive stress dominates in the medial plane while tensile stress in the lateral plane of the femur. The corresponding stress levels of intact femur for walking and stair-climbing load cases are 22 and 29 MPa, respectively. The magnitude of Tresca stress for the THA femur in stair-climbing load case remains higher in the region of 85 MPa while the walking load case induces around 40 MPa. The stress range in the straight and single taper stem prosthesis is lower than 260 MPa, while localized Tresca stress is in the order of the yield strength of Ti-6Al-4V alloy for double and triple taper stem design.

Effect of joining the sectioned implant-supported prosthesis on the peri-implant strain generated in simulated mandibular model.

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Singh, Ipsha; Nair, K Chandrasekharan; Shetty, Jayakar

2017-01-01

The aim of this study is to evaluate the strain developed in simulated mandibular model before and after the joining of an implant-supported screw-retained prosthesis by different joining techniques, namely, arc welding, laser welding, and soldering. A specimen simulating a mandibular edentulous ridge was fabricated in heat-cured acrylic resin. 4-mm holes were drilled in the following tooth positions; 36, 33, 43, 46. Implant analogs were placed in the holes. University of California, Los Angeles, abutment was attached to the implant fixture. Eight strain gauges were attached to the acrylic resin model. Six similar models were made. Implant-supported screw-retained fixed prosthesis was fabricated in nickel-chromium alloy. A load of 400 N was applied on the prosthesis using universal testing machine. Resultant strain was measured in each strain gauge. All the prostheses were sectioned at the area between 36 and 33, 33 and 43, and 43 and 46 using 35 micrometer carborundum disc, and strain was measured in each strain gauge after applying a load of 400 N on the prosthesis. Specimens were joined by arc welding, soldering, and laser welding. After joining, a load of 400 N was applied on each prosthesis and the resultant strain was measured in each strain gauge. Highest mean strain values were recorded before sectioning of the prostheses (889.9 microstrains). Lowest mean strain values were recorded after sectioning the prosthesis and before reuniting it (225.0 microstrains). Sectioning and reuniting the long-span implant prosthesis was found to be a significant factor in influencing the peri-implant strain.

[The esthetics of lower limb prosthesis].

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Gardrat, Franck

2015-01-01

The amputation, which is upper or lower limb, entails important consequences and often traumatic into subject amputee from a physical, psychological, interpersonal and social point of view. It acts on the body image unleashing different psychological disorders and alterations in the social and professional reality. The aesthetic prosthesis can be considered a good support to help the person regain a new body image of themselves, facilitating the process of physical rehabilitation and social integration.

Impact of removable partial denture prosthesis on chewing efficiency

Science.gov (United States)

BESSADET, Marion; NICOLAS, Emmanuel; SOCHAT, Marine; HENNEQUIN, Martine; VEYRUNE, Jean-Luc

2013-01-01

Removable partial denture prostheses are still being used for anatomic, medical and economic reasons. However, the impact on chewing parameters is poorly described. Objectives The objective of this study was to estimate the impact of removable partial denture prosthesis on masticatory parameters. Material and Methods Nineteen removable partial denture prosthesis (RPDP) wearers participated in the study. Among them, 10 subjects were Kennedy Class III partially edentulous and 9 with posterior edentulism (Class I). All presented a complete and full dentate opposing arch. The subjects chewed samples of carrots and peanuts with and without their prosthesis. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Number of chewing cycles (CC), chewing time (CT) and chewing frequency (CF=CC/CT) were video recorded. Results With RPDP, the mean D50 values for carrot and peanuts were lower [Repeated Model Procedures (RMP), F=15, p<0.001] regardless of the type of Kennedy Class. For each food, mean CC, CT and CF values recorded decreased (RMP, F=18, F=9, and F=20 respectively, p<0.01). With or without RPD, the boluses' granulometry values were above the masticatory normative index (MNI) determined as 4,000 µm. Conclusion RPDP rehabilitation improves the ability to reduce the bolus particle size, but does not reestablish fully the masticatory function. Clinical relevance This study encourages the clinical improvement of oral rehabilitation procedure. PMID:24212983

Pseudo-capsule “coffin effect”: How to prevent penile retraction after implant of three-piece inflatable prosthesis

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Enrico Caraceni

2014-06-01

Full Text Available Objective: Following three-component implantation of a penile prosthesis, some patients are dissatisfied with their penile length. This may be due to the procedure by itself or pre-existing risk factors or psychological reasons. We supposed that formation of a restricted pseudo-capsule due to a late prosthesis activation can inhibit later system expansion. We aimed to identify the presence or absence of penile retraction after implant and to prevent it by immediate prosthesis activation after implantation. Material and methods. Forty-six patients operated with three-piece inflatable penile prosthesis (AMS 700 CX o LGX were enrolled. In 27 patients prosthesis was first activated four weeks after surgery (NEA group and in 19 patients prosthesis was activated immediately after surgery (DEA group. Length and girth of the penis was evaluated before (in DEA group and after the surgical procedure. Results. The average post implant dorsal length of the erect penis in group NEA was found 3.28 cm shorter than in group with early activation (DEA. In DEA group there was no lenght difference between pre-operative stretching (14.57 cm and post operative erection (14.98 cm. When early activation was not performed, the clinical result was a smaller penis in erect phase. Conclusion. Reduced lenght of the penis after implantation can be caused by the presence of a pseudo-capsule that limits the elongation of the prosthesis and of the penis (“coffin effect”. Timing of first activation seems to be the key in order to prevent the risk of penile retraction after implantation. Early activation is identified as the best measure to maintain the length of the pre implant erect penis after the prosthetic hydraulic implant.

Penile prosthesis implantation in Chinese patients with severe erectile dysfunction: 10-year experience

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Song, Wei-Dong; Yuan, Yi-Ming; Cui, Wan-Shou; Wu, Alex K; Zhu, Yi-Chen; Liu, Jing; Wang, Lin; Bai, Guang-Yi; Peng, Jing; Zhang, Zhi-Chao; Gao, Bing; Guo, Ying-Lu; Lue, Tom F; Xin, Zhong-Cheng

2013-01-01

We retrospectively evaluated the clinical outcome of penile prosthesis implantation (PPI) in Chinese patients with severe erectile dysfunction (SED). From July 2000 to December 2011, 224 patients (mean age: 35.9±11.8 years, range: 20–75 years) with SED underwent PPI by experienced surgeon according to standard PPI procedure at our centre. A malleable prosthesis (AMS 650) was implanted in 45 cases (20.1%), and a three-piece inflatable prosthesis (AMS 700 CXM or AMS 700 CXR) was implanted in 179 cases (79.9%). Surgical outcomes, including postoperative complications, clinical efficacy and couple satisfaction, were evaluated over than 6 months postoperatively using medical record abstraction, IIEF-5, quality of life (QoL) scores, and the patient/partner sexual satisfaction score proposed by Bhojwani et al. Of the 224 patients eligible for the study, 201 subjects (89.7%) completed follow-up. All of patients could perform sexual intercourse post PPI with the mean postoperative IIEF-5 and QoL scores were 20.02±2.32 and 5.28±0.76, respectively, which were significantly improved compared with the preoperative scores (6.29±1.5 and 2.13±0.84, Preported by 178 men (88.6%), and overall satisfaction with the PPI surgery was reported by 89.0% of men and 82.5% of partners. Patient satisfaction in the three-piece inflatable prosthesis group was higher than in the malleable prosthesis group (P<0.05). Satisfaction, however, between the types of prostheses, did not differ in the partner survey. PPI is a safe and effective treatment option for Chinese patients with SED and experienced surgeon perform PPI according to standard PPI procedure could reduce the postoperative complications of PPI and could improve patient satisfaction ratio and QoL. PMID:23872664

Debridement, antibiotics, irrigation, and retention (DAIR) of the prosthesis after hip hemiarthroplasty infections. Does it work?

Science.gov (United States)

Kazimoglu, Cemal; Yalcin, Nadir; Onvural, Burak; Akcay, Serkan; Agus, Haluk

2015-08-01

Debridement, antibiotic, and implant retention (DAIR) is an attractive treatment modality after hip hemiarthroplasty (HA) infections. Data about the success of the procedure after acute onset infections is lacking. The aim of this study was to analyze the clinical outcome and associated risk factors. A multicenter, retrospective cohort study was designed, including 39 patients with acute onset prosthetic infection who had undergone debridement and irrigation with prosthesis retention. The primary outcome measure was infection eradication without prosthesis removal. We also analyzed how the success rate was influenced by the length of the interval between implantation of the prosthesis and the beginning of the treatment. The overall success rate was 41%. Sedimentation rate over 60 mm/h and the longer duration (2 weeks) after prosthesis implantation were found as factors negatively influencing the success rate. Our results indicated limited success to DAIR- treated patients with infected HA. The high failure rate of DAIR treatment after 2 weeks from the implantation should be taken into consideration.

Chest-wall reconstruction with a customized titanium-alloy prosthesis fabricated by 3D printing and rapid prototyping.

Science.gov (United States)

Wen, Xiaopeng; Gao, Shan; Feng, Jinteng; Li, Shuo; Gao, Rui; Zhang, Guangjian

2018-01-08

As 3D printing technology emerge, there is increasing demand for a more customizable implant in the repair of chest-wall bony defects. This article aims to present a custom design and fabrication method for repairing bony defects of the chest wall following tumour resection, which utilizes three-dimensional (3D) printing and rapid-prototyping technology. A 3D model of the bony defect was generated after acquiring helical CT data. A customized prosthesis was then designed using computer-aided design (CAD) and mirroring technology, and fabricated using titanium-alloy powder. The mechanical properties of the printed prosthesis were investigated using ANSYS software. The yield strength of the titanium-alloy prosthesis was 950 ± 14 MPa (mean ± SD), and its ultimate strength was 1005 ± 26 MPa. The 3D finite element analyses revealed that the equivalent stress distribution of each prosthesis was unifrom. The symmetry and reconstruction quality contour of the repaired chest wall was satisfactory. No rejection or infection occurred during the 6-month follow-up period. Chest-wall reconstruction with a customized titanium-alloy prosthesis is a reliable technique for repairing bony defects.

Prosthetic rehabilitation of mandibular defects with fixed-removable partial denture prosthesis using precision attachment: A twin case report

Directory of Open Access Journals (Sweden)

Vimal Kantilal Munot

2017-01-01

Full Text Available The restoration of normal function and esthetic appearance with a dental prosthesis is a major challenge in the rehabilitation of patients who have lost their teeth and surrounding bone because of surgery for oral cyst or tumor. Rehabilitation with fixed or removable prosthesis is even more challenging when the edentulous span is long and the ridge is defective. Anatomic deformities and unfavorable biomechanics encountered in the region of resection add to the misery. In such situation, a fixed-removable prosthesis allows favorable biomechanical stress distribution along with restoration of esthetics, phonetics, comfort, hygiene, and better postoperative care and maintenance. This article describes rehabilitation of two cases with mandibular defects with an attachment-retained fixed-removable hybrid prosthesis.

COMPARISON OF CULTURE OF SYNOVIAL FLUID, PERIPROSTHETIC TISSUE AND PROSTHESIS SONICATE FOR THE DIAGNOSIS OF KNEE PROSTHESIS INFECTION

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Andrej Trampuž

2003-03-01

Full Text Available Background. Synovial fluid and periprosthetic tissue specimens are the standard specimens cultured for the diagnosis of prosthetic joint infection (PJI. We hypothesize that ultrasonication of the explanted prosthesis may improve diagnosis of PJI by dislodging biofilm bacteria from the prosthesis surface and improve the sensitivity and specificity of diagnosis of PJI.Methods. Included were patients undergoing knee prosthesis exchange for septic or biomechanical failure and have not received antimicrobial therapy in the last 2 weeks prior specimen collection. Cultures of synovial fluid and periprosthetic tissue specimens were performed per the usual clinical practice. Additionally, explanted joint components were sonicated for 5 minutes at frequency 40 kHz in sterile Ringer’s solution; aliquots of 0.5 ml sonicate were plated onto five aerobic and five anaerobic blood agar plates, and incubated at 37 °C and examined for the next seven days. The number and identity of each colony morphology was recorded.Results. 35 patients undergoing knee replacement have been studied (24 for aseptic biomechanical failure and 11 for suspected PJI. In patients with PJI, coagulase-negative staphylococci (7 cases, Corynebacterium spp. (2 cases, Staphylococcus aureus (1 case, and viridans group streptococcus (1 case were recovered. Culture sensitivity and specificity were for synovial fluid 88% and 100%, for periprosthetic tissue 83% and 81%, and for explant sonicate 91% and 100%, respectively. In sonicate cultures higher numbers of microorganisms than in periprosthetic tissue cultures were consistently detected.Conclusions. Using synovial fluid, periprosthetic tissue, and explant sonicate cultures, 12%, 17% and 9% of PJI were missed, respectively. Explant sonicate cultures were the most sensitive with respect to the diagnosis of PJI, indicating that explant ultrasonication may improve bacterial recovery. In sonicate cultures, infecting organisms were detected in

The clinical relevance of advanced artificial feedback in the control of a multi-functional myoelectric prosthesis.

Science.gov (United States)

Markovic, Marko; Schweisfurth, Meike A; Engels, Leonard F; Bentz, Tashina; Wüstefeld, Daniela; Farina, Dario; Dosen, Strahinja

2018-03-27

To effectively replace the human hand, a prosthesis should seamlessly respond to user intentions but also convey sensory information back to the user. Restoration of sensory feedback is rated highly by the prosthesis users, and feedback is critical for grasping in able-bodied subjects. Nonetheless, the benefits of feedback in prosthetics are still debated. The lack of consensus is likely due to the complex nature of sensory feedback during prosthesis control, so that its effectiveness depends on multiple factors (e.g., task complexity, user learning). We evaluated the impact of these factors with a longitudinal assessment in six amputee subjects, using a clinical setup (socket, embedded control) and a range of tasks (box and blocks, block turn, clothespin and cups relocation). To provide feedback, we have proposed a novel vibrotactile stimulation scheme capable of transmitting multiple variables from a multifunction prosthesis. The subjects wore a bracelet with four by two uniformly placed vibro-tactors providing information on contact, prosthesis state (active function), and grasping force. The subjects also completed a questionnaire for the subjective evaluation of the feedback. The tests demonstrated that feedback was beneficial only in the complex tasks (block turn, clothespin and cups relocation), and that the training had an important, task-dependent impact. In the clothespin relocation and block turn tasks, training allowed the subjects to establish successful feedforward control, and therefore, the feedback became redundant. In the cups relocation task, however, the subjects needed some training to learn how to properly exploit the feedback. The subjective evaluation of the feedback was consistently positive, regardless of the objective benefits. These results underline the multifaceted nature of closed-loop prosthesis control as, depending on the context, the same feedback interface can have different impact on performance. Finally, even if the closed

Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment

Science.gov (United States)

Lee, Christine; Tu, Hong Anh; Weir, Mark; Holubowich, Corinne

2016-01-01

Background Retinitis pigmentosa is a group of genetic disorders that involves the breakdown and loss of photoreceptors in the retina, resulting in progressive retinal degeneration and eventual blindness. The Argus II Retinal Prosthesis System is the only currently available surgical implantable device approved by Health Canada. It has been shown to improve visual function in patients with severe visual loss from advanced retinitis pigmentosa. The objective of this analysis was to examine the clinical effectiveness, cost-effectiveness, budget impact, and safety of the Argus II system in improving visual function, as well as exploring patient experiences with the system. Methods We performed a systematic search of the literature for studies examining the effects of the Argus II retinal prosthesis system in patients with advanced retinitis pigmentosa, and appraised the evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria, focusing on visual function, functional outcomes, quality of life, and adverse events. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care over a 10-year time horizon. We also conducted a 5-year budget impact analysis. We used a qualitative design and an interview methodology to examine patients’ lived experience, and we used a modified grounded theory methodology to analyze information from interviews. Transcripts were coded, and themes were compared against one another. Results One multicentre international study and one single-centre study were included in the clinical review. In both studies, patients showed improved visual function with the Argus II system. However, the sight-threatening surgical complication rate was substantial. In the base-case analysis, the Argus II system was cost-effective compared with standard care only if willingness-to-pay was more than $207,616 per quality-adjusted life

Design and validation of a foldable and photovoltaic wide-field epiretinal prosthesis.

Science.gov (United States)

Ferlauto, Laura; Airaghi Leccardi, Marta Jole Ildelfonsa; Chenais, Naïg Aurelia Ludmilla; Gilliéron, Samuel Charles Antoine; Vagni, Paola; Bevilacqua, Michele; Wolfensberger, Thomas J; Sivula, Kevin; Ghezzi, Diego

2018-03-08

Retinal prostheses have been developed to fight blindness in people affected by outer retinal layer dystrophies. To date, few hundred patients have received a retinal implant. Inspired by intraocular lenses, we have designed a foldable and photovoltaic wide-field epiretinal prosthesis (named POLYRETINA) capable of stimulating wireless retinal ganglion cells. Here we show that within a visual angle of 46.3 degrees, POLYRETINA embeds 2215 stimulating pixels, of which 967 are in the central area of 5 mm, it is foldable to allow implantation through a small scleral incision, and it has a hemispherical shape to match the curvature of the eye. We demonstrate that it is not cytotoxic and respects optical and thermal safety standards; accelerated ageing shows a lifetime of at least 2 years. POLYRETINA represents significant progress towards the improvement of both visual acuity and visual field with the same device, a current challenging issue in the field.

Natural Marine and Synthetic Xenobiotics Get on Nematode’s Nerves: Neuro-Stimulating and Neurotoxic Findings in Caenorhabditis elegans

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Thora Lieke

2015-05-01

Full Text Available Marine algae release a plethora of organic halogenated compounds, many of them with unknown ecological impact if environmentally realistic concentrations are applied. One major compound is dibromoacetic acid (DBAA which was tested for neurotoxicity in the invertebrate model organism Caenorhabditis elegans (C. elegans. This natural compound was compared with the widespread synthetic xenobiotic tetrabromobisphenol-A (TBBP-A found in marine sediments and mussels. We found a neuro-stimulating effect for DBAA; this is contradictory to existing toxicological reports of mammals that applied comparatively high dosages. For TBBP-A, we found a hormetic concentration-effect relationship. As chemicals rarely occur isolated in the environment, a combination of both organobromines was also examined. Surprisingly, the presence of DBAA increased the toxicity of TBBP-A. Our results demonstrated that organohalogens have the potential to affect single organisms especially by altering the neurological processes, even with promoting effects on exposed organisms.

The Use of CAD/CAM Trial Pattern for Facial Prosthesis Fabrication of a Maxillofacial Patient with Large Defect

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Nina Ariani

2017-12-01

Full Text Available Treatment of maxillofacial patients needs a multidisciplinary approach of several expertise based on the complexityof the case. Prosthodontists often work together with e.g. ENT, oral or plastic surgeons to provide patient with betterprosthesis and optimum treatment. Case report: A 55 years old male was referred to Dental Teaching Hospital ofUniversitas Indonesia for facial prosthesis fabrication. Patient had undergone squamous cell carcinoma ablationsurgery that encompassed nose, cheek, sinuses, upper lip and most of the hard palate. Due to the extensive natureof the defect, Department of Prosthodontics collaborated with Department of Biomedical Engineering to employ3D printing technique using general purpose machine for fabricating the trial pattern for the prosthesis, withattention given especially to margin areas and facial contours. This technique helps for prosthesis fabrication ofthis patient because manual wax carving is no longer necessary. Wax carving usually is a labor/skill intensive stepand takes longer time. Conclusion: 3D printing of the trial pattern for the prosthesis help minimizes the labor/skill intensive part of facial prosthesis fabrication.

Quantitating the effect of prosthesis design on femoral remodeling using high-resolution region-free densitometric analysis (DXA-RFA)

DEFF Research Database (Denmark)

Farzi, Mohsen; Morris, Richard M; Penny, Jeannette

2017-01-01

Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs are not ......Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs...... using scans acquired during two previous randomized clinical trials (2004 to 2009); one comparing three cemented prosthesis design geometries, and the other comparing a hip resurfacing versus a conventional cementless prosthesis. DXA RFA resolved subtle differences in magnitude and area of bone...... remodeling between prosthesis designs not previously identified in conventional DXA analyses. A mean bone loss of 10.3%, 12.1%, and 11.1% occurred for the three cemented prostheses within a bone area fraction of 14.8%, 14.4%, and 6.2%, mostly within the lesser trochanter (p 

Cross-cultural validation of the Prosthesis Evaluation Questionnaire in vascular amputees fitted with prostheses in Spain.

Science.gov (United States)

Benavent, Jose Vicente; Igual, Celedonia; Mora, Enrique; Antonio, Rosa; Tenias, Jose Maria

2016-12-01

The lack of specific prosthetic-related outcome instruments for Spanish amputees must be addressed. To elaborate a culturally equivalent version of the Prosthesis Evaluation Questionnaire in the Spanish language. Cross-cultural questionnaire validation. Two-step process for cultural adaptation: forward and backward translations of English original and Spanish translated versions; assessment of both construct and criterion validity and reliability in a group of vascular amputees. A total of 61 patients were recruited, 44 men (72.1%) and 17 women (27.9%), with a median age of 71.1 years (standard deviation: 7.7 years; range: 51-87 years). In the Prosthesis Evaluation Questionnaire-Spanish, the lowest scores were for gait and frustration, and the highest scores were for noise and stump health. Internal consistency of the questionnaire was acceptable (>0.70) for four of the scales used in the Prosthesis Evaluation Questionnaire but poor (<0.50) for the scales relating to appearance and stump health. Correlations with the quality-of-life levels as measured by the Short Form-36 were positive and mostly significant. Prosthesis Evaluation Questionnaire-Spanish could assess the quality of life in patients who have undergone vascular amputations and then been fitted with a prosthetic limb. The questionnaire shows adequate criteria validity when compared with other instruments for measuring quality of life. The Prosthesis Evaluation Questionnaire-Spanish could be a valid and reliable instrument for assessing adaptation to prostheses in vascular amputees. The questionnaire adds information relevant to the patient and the physician and may identify cases with poor expected adaptation to the prosthesis. © The International Society for Prosthetics and Orthotics 2015.

Design of a Fully-Passive Transfemoral Prosthesis Prototype

NARCIS (Netherlands)

Behrens, Sebastiaan Maria; Behrens, S.M.; Ünal, Ramazan; Unal, R.; Hekman, Edsko E.G.; Carloni, Raffaella; Stramigioli, Stefano; Koopman, Hubertus F.J.M.

In this study, we present the mechanical design of a prototype of a fully-passive transfemoral prosthesis for normal walking. The conceptual working principle at the basis of the design is inspired by the power flow in human gait, with the main purpose of realizing an energy efficient device. The

Effect of joining the sectioned implant-supported prosthesis on the peri-implant strain generated in simulated mandibular model

Directory of Open Access Journals (Sweden)

Ipsha Singh

2017-01-01

Full Text Available Aim: The aim of this study is to evaluate the strain developed in simulated mandibular model before and after the joining of an implant-supported screw-retained prosthesis by different joining techniques, namely, arc welding, laser welding, and soldering. Materials and Methods: A specimen simulating a mandibular edentulous ridge was fabricated in heat-cured acrylic resin. 4-mm holes were drilled in the following tooth positions; 36, 33, 43, 46. Implant analogs were placed in the holes. University of California, Los Angeles, abutment was attached to the implant fixture. Eight strain gauges were attached to the acrylic resin model. Six similar models were made. Implant-supported screw-retained fixed prosthesis was fabricated in nickel-chromium alloy. A load of 400 N was applied on the prosthesis using universal testing machine. Resultant strain was measured in each strain gauge. All the prostheses were sectioned at the area between 36 and 33, 33 and 43, and 43 and 46 using 35 micrometer carborundum disc, and strain was measured in each strain gauge after applying a load of 400 N on the prosthesis. Specimens were joined by arc welding, soldering, and laser welding. After joining, a load of 400 N was applied on each prosthesis and the resultant strain was measured in each strain gauge. Results: Highest mean strain values were recorded before sectioning of the prostheses (889.9 microstrains. Lowest mean strain values were recorded after sectioning the prosthesis and before reuniting it (225.0 microstrains. Conclusions: Sectioning and reuniting the long-span implant prosthesis was found to be a significant factor in influencing the peri-implant strain.

To Compare the Effect of Pre and Post Weight Bearing Anxiety, Depression in Conventional and Modular Prosthesis on Unilateral Transtibial Amputees

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R. Raja

2014-01-01

Full Text Available Aims and Objectives: To compare the effect of anxiety and depression on unilateral trans tibial amputees those who are using conventional and modular patellar tendon bearing (PTB prosthesis with stump exercises. Material and Methods: A sample of 40 persons with below knee amputation who were trained to wear prosthesis were studied with an experimental comparative study design. Patients who were admitted at Kempegowda Institute of Medical Sciences and Research Centre, Bangalore, K. S. Hegde Medical Academy and Research Centre Mangalore, (N=150 who underwent unilateral transtibial, transfemoral and other amputations between August 2009 - December 2011. To find out peri and postoperative prosthetic fitting, anxiety and depression level of transtibial amputees who wear conventional and modular PTB prosthesis. 3 years of experimental comparative study reveals that the outcome measures of peri and post-operative anxiety and depression level while using conventional PTB prosthesis with stump exercises and modular PTB prosthesis with stump exercises on unilateral transtibial amputees. Results: The unilateral transtibial amputees who were trained with modular prosthesis along with stump exercises group patients anxiety and depression levels are reduced as compared to the unilateral transtibial amputees who were trained with conventional PTB prosthesis along with stump exercises. There is no significant difference seen in both the groups while giving stump exercises alone. Conclusion: The unilateral transtibial amputees who were trained with modular prosthesis along with stump exercises group, patient’s anxiety and depression levels are reduced drastically.

Treatment of sharp mandibular alveolar process with hybrid prosthesis

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Sukaedi Sukaedi

2010-09-01

Full Text Available Background: Losing posterior teeth for a long time would occasionally lead to the sharpening of alveolar process. The removable partial denture usually have problems when used during mastication, because of the pressure on the mucosa under the alveolar ridge. Purpose: The purpose of this case report was to manage patients with sharp mandibular alveolar process by wearing hybrid prosthesis with extra coronal precision attachment retention and soft liner on the surface base beneath the removable partial denture. Case: A 76 years old woman visited the Prosthodontic Clinic Faculty of Dentistry Airlangga University. The patient had a long span bridge on the upper jaw and a free end acrylic removable partial denture on the lower jaw. She was having problems with mastication. The patient did not wear her lower denture because of the discomfort with it during mastication. Hence, she would like to replace it with a new removable partial denture. Case management: The patient was treated by wearing a hybrid prosthesis with extra coronal precision attachment on the lower jaw. Soft liner was applied on the surface of the removable partial denture. Hybrid prosthesis is a complex denture consisting of removable partial denture and fixed bridge. Conclusion: It concluded that after restoration, the patient had no problems with sharp alveolar process with her new denture, and she was able to masticate well.Latar belakang: Kehilangan geligi posterior dapat menimbulkan processus alveolaris tajam. Gigi tiruan sebagian lepasan mempunyai masalah selama pengunyahan karena adanya tekanan di mukosa di bawah alveolar ridge. Tujuan: Tujuan laporan kasus ini adalah untuk menjelaskan cara menangani pasien yang mempunyai prosesus alveolaris yang tajam di rahang bawah dengan dibuatkan protesis hybrid dengan daya tahan extra coronal precision attachment dan soft liner di permukaan bawah basis gigi tiruan sebagian lepasan. Kasus: Pasien wanita berumur 76 tahun datang di klinik

Removable dental prosthesis as periodontal treatment method

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Aprilia Adenan

2007-11-01

Full Text Available The objectives of prostheses are to restore mastication force, improve esthetics and maintain gingival health. The construction and function of prosthesis restoration are mutually interdependent with condition of periodontal tissues. A properly constructed prosthesis is an integral phase of complete treatment of periodontal disease in order to maintain periodontal tissues health. This paper reports case of a man aged 47 years who came to Dental Specialist Clinic in Oral and Dental Hospital Faculty of Dentistry Universitas Padjadjaran with chief complaint of mobility in almost all his teeth and they seems to look longer. The patient has no systemic disease and did not want his teeth to be extracted. Clinical and panoramic radiographic and laboratoris examinations has been done. During treatment, oclusal adjustment and splinting had been done on tooth 33,34,35 and tooth 44,43 also tooth 43,42 splinting with composite. The following treatment was the acrylic removable partial denture for upper jaw while mandible was fitted a frame denture which functioned as a semi permanent splint. One month post treatment, patien felt comfort and the denture was well functioning.

Excessive strut wear allowing ball-poppet embolization in a DeBakey-Surgitool aortic valve prosthesis.

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Sutherland, R D; Guynes, W A; Nichols, C T; Martinez, H E

1982-01-01

Excessive cage strut wear allowing ball-poppet embolization caused the sudden death of a 47 year old lady in whom a DeBakey-Surgitool aortic prosthesis had been implanted nine years earlier. Patients with this type of prosthesis should have periodic valvular cine fluoroscopy with image intensification to allow visualization of significant strut wear or fracture, and appropriate prosthetic valve replacement.

Extended long term functional outcome of inflatable penile prosthesis in a single institution.

LENUS (Irish Health Repository)

Thomas, A Z

2011-02-01

We sought to evaluate the extended long term functional outcome of the AMS700 three piece inflatable prosthesis in men with erectile dysfunction in a single urological department and assess our revision rates. Patients that underwent first-time insertion or revision of an AMS700 3 piece inflatable penile prosthesis between 1984-2007 were included. Data was obtained from medical records and long term follow up of patients was conducted by telephone interview. The medical records of 38 patients were available for review. Of these 38 men, 56 prostheses were inserted. The mean follow up was 8.4 years (101 months). The revision rate at 50 months postoperatively was 7\\/38 (18%). The overall revision rate was 18\\/38 (47%). The mean time to revision in these 18 patients was 72 months (12-156 months) after initial insertion of AMS700 penile prosthesis. This study highlights that with longer follow u revision rates markedly increase after 72 months.

Modified cementless total coxofemoral prosthesis: development, implantation and clinical evaluation

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S.A. Arias

2013-12-01

Full Text Available The aim of this study was to modify canine coxofemoral prostheses and the clinical evaluation of the implantation. Fifteen canine hips and femora of cadavers were used in order to study the surface points of modification in prostheses and develop a perforation guide. Femoral stems and acetabular components were perforated and coated with biphasic calcium phosphate layer. Twelve young adult male mongrel dogs were implanted with coxofemoral prostheses. Six were operated upon and implanted with cemented canine modular hip prostheses, establishing the control group. The remaining six were implanted with a novel design of cementless porous tricalcic phosphate-hydroxyapatite coated hip prostheses. Clinical and orthopedic performance, complications, and thigh muscular hypotrophy were assessed up to the 120th post-operatory day. After 120 days, animals with cementless prostheses had similar clinical and orthopedic performance compared to the cemented group despite the increased pain thigh hypotrophy. Animals that underwent cementless hip prosthesis evidenced more pain, compared to animals with cemented hip prosthesis that required longer recuperation time. No luxations, two fractures and two isquiatic neurapraxies were identified in the course of the study. Using both the cemented and the bioactive coated cementless model were suitable to dogs, showing clinical satisfactory results. Osseointegration and biological fixation were observed in the animals with the modified cementless hip prosthesis.

Reconstruction of chronic acromioclavicular joint disruption with artificial ligament prosthesis

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Chouhan Devendra Kumar

2013-08-01

Full Text Available 【Abstract】Objective: Management of Rockwood type 3 acromioclavicular disruptions is a matter of debate. Should we adopt conservative or operative measures at first presentation? It is not clear but most of the evidences are in favour of conservative management. We present our expe-rience in managing these patients surgically. Methods: We present a prospective series of eight cases of chronic Rockwood type 3 acromioclavicular joint disruptions treated surgically. Anatomical reconstruction of the coracoclavicular ligament was done by artificial braided polyester ligament prosthesis. Results: All the patients were able to perform daily activities from an average of the 14th postoperative day. All patients felt an improvement in pain, with decrease in ave-rage visual analogue scale from preoperative 6.5 points (range 3-9 points to 2.0 points (range 0-5 points, Constant score from 59% to 91% and American Shoulder and Elbow Surgeons shoulder score from 65 to 93 points postoperatively. These results improved or at least remained stationary on midterm follow-up, and no deterioration was recorded at an average follow-up of 46 months. Conclusion: This midterm outcome analysis of the artificial ligament prosthesis is the first such follow-up study with prosthesis. Our results are encouraging and justify the further use and evaluation of this relatively new and easily reproducible technique. Key words: Acromioclavicular joint; Prostheses and implants; Reconstructive surgical procedures; Ligaments

Task-Oriented Gaming for Transfer to Prosthesis Use

NARCIS (Netherlands)

van Dijk, Ludger; Sluis, van der Corry K.; van Dijk, Hylke W.; Bongers, Raoul M.

2016-01-01

The aim of this study is to establish the effect of task-oriented video gaming on using a myoelectric prosthesis in a basic activity of daily life (ADL). Forty-one able-bodied right-handed participants were randomly assigned to one of four groups. In three of these groups the participants trained to

[Medial unicompartmental knee prosthesis for patients with unicompartmental gonarthrosis

NARCIS (Netherlands)

Kort, N.P.; Deutman, R.; Raay, J.J. van; Horn, J.R. van

2004-01-01

The function and survival time of unicompartmental knee prostheses for patients with severe gonarthrosis have been improved the past few years by developments in their design, the instrumentarium and the surgical technique. A medial unicompartmental knee prosthesis may be indicated in patients with

Survey on the Contemporary Management of Intraoperative Urethral Injuries During Penile Prosthesis Implantation.

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Sexton, Stephanie J; Granieri, Michael A; Lentz, Aaron C

2018-04-01

Intraoperative urethral injury is an uncommon event during the placement of a penile prosthesis, and alternative management strategies have been proposed with continuation of implantation after urethral injury. To evaluate surgeon practices in the management of intraoperative urethral injury. An online survey was sent to the society listservs of the Genitourinary Reconstructive Surgeons (GURS) and the Sexual Medicine Society of North America (SMSNA). Physicians were queried on their fellowship training, experience with penile prosthesis implantation, and management of urethral injuries during prosthesis placement. The response data were analyzed using SAS 9.4 (SAS Institute, Cary, NC, USA). The χ 2 test and Fisher exact test were used to determine associations between variables. Survey responses. 131 survey responses were analyzed. Of the responders, 41.2% were GURS fellowship trained, 19.1% were SMSNA trained, 30.5% were non-fellowship trained, and 9.2% were trained in other fellowships. 25.4% of participants performed more than 50 implantations per year, 37.7% performed 20 to 50 per year, and 36.9% performed fewer than 20 per year. Urethral injury during prosthesis implantation was uncommon, with 26.2% reporting 0 injury, 58.5% reporting 1 to 3 injuries, and 15.4% reporting more than 3 career injuries. Injuries were most commonly encountered during corporal dilation (71.1%) compared with corporal exposure (12.5%) or penile straightening maneuvers (7.0%). There was no statistically significant difference with aborting or continuing implantation among GURS-trained, SMSNA-trained, other fellowship-trained, and non-fellowship-trained surgeons. Of all responders, 55% would abort the procedure after distal urethral injury, whereas 45% would continue the procedure with unilateral or bilateral insertion of cylinders. Patient factors that increased likelihood of terminating the procedure in the case of urethral injury included immunosuppression, spinal cord injury, and

Modified prosthesis for the treatment of malignant esophagotracheal fistula

International Nuclear Information System (INIS)

Buess, G.; Schellong, H.; Kometz, B.; Gruessner, R.J.; Junginger, T.

1988-01-01

Esophagotracheal fistula is usually a sequela of irradiation or laser treatment of advanced carcinoma of the esophagus or the tracheobronchial tree. Resection of the tumor in these cases is not possible, and palliative bypass surgery is highly risky. The peroral placement of a prosthesis is less invasive, but conventional prostheses often fail to occlude the fistula. The authors regularly use an endoscopic multiple-diameter bougie for dilation. After dilation, a specially designed prosthesis is pushed through the tumor stenosis to block the fistula. This procedure can be done without general anesthesia. The funnels of conventional prostheses cannot cover the fistula when there is either a wide, proximal esophagus above the fistula or a high fistula. To cope with this particular situation, a special fistula funnel was developed. It perfectly occludes the fistulas in all patients. Of 21 patients, 19 were discharged without further aspiration

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users.

Science.gov (United States)

Sawers, Andrew; Hafner, Brian J

2018-05-08

Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Cross-sectional. Unilateral lower-limb prosthesis users. Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalized distance walked. Heuristic rules were applied to determine whether the narrowing beam task was "too easy," "too hard," or "appropriately challenging" for each participant. Linear regression and Bland-Altman plots were used to determine whether combinations of the first 5 trials could predict participants' stable beam-walking performance. Forty unilateral lower-limb prosthesis users participated. Narrowing beam-walking was appropriately challenging for 98% of participants. Performance stabilized for 93% of participants within 5 trials, while 62% were stable across all trials. The mean of trials 3-5 accurately predicted stable performance. A clinical narrowing beam-walking test is likely to challenge a range of lower-limb prosthesis users, have minimal administrative burden, and exhibit no floor or ceiling effects. Narrowing beam-walking is therefore a clinically viable method to evaluate lower-limb prosthesis users' balance ability, but requires psychometric testing before it is used to assess fall risk.

The effects of indwelling voice prosthesis on the quality of life, depressive symptoms, and self-esteem in patients with total laryngectomy.

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Polat, Beldan; Orhan, Kadir Serkan; Kesimli, Mustafa Caner; Gorgulu, Yasemin; Ulusan, Murat; Deger, Kemal

2015-11-01

This study aims to evaluate the effects of voice rehabilitation with indwelling voice prosthesis on quality of life, depression, anxiety, self-esteem, and sexual functions in laryngectomy patients. Provox-1 was applied to 30 patients who underwent total laryngectomy by opening a tracheoesophageal fistula. WHO Quality of Life-BREF, Beck Depression Inventory, Beck Anxiety Inventory, Rosenberg Self-Esteem Scale, Arizona Sexual Experience Scale forms were asked to be filled out by the patients before voice prosthesis application. These tests were asked to be filled out again 3 months later after the voice prosthesis application. Paired samples and Wilcoxon tests were used to compare before and after operation values. Indwelling voice prosthesis was found to improve quality of life, self-esteem, and sexual function (p < 0.05). Additionally, symptoms of depression and anxiety were regressed (p < 0.05). Indwelling voice prosthesis was found to especially increase the quality of life and decrease depression (p < 0.05). This study is an uncontrolled single-arm study comparing patients' psychosocial statuses pre- and post-voice prosthesis.

TOTAL ANKLE ARTHROPLASTY: BRAZILIAN EXPERIENCE WITH THE HINTEGRA PROSTHESIS.

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Nery, Caio; Fernandes, Túlio Diniz; Réssio, Cibele; Fuchs, Mauro Luiz; Godoy Santos, Alexandre Leme de; Ortiz, Rafael Trevisan

2010-01-01

Ankle arthrosis is becoming more and more common. The search for solutions that preserve joint function has led to a new generation of prosthesis with three components and more degrees of freedom. This paper presents the results achieved for ten patients treated with the HINTEGRA Prosthesis (Integra, New Deal), through collaborative action between the Foot and Ankle Groups of the Orthopedics and Traumatology divisions of Escola Paulista de Medicina, Unifesp, and the School of Medicine of the University of São Paulo (USP). The ten patients (six women and four men, aged between 29 and 66 years), underwent a surgical procedure consisting of Hintermann's technique, between January and June 2005. They were evaluated at prearranged intervals, and the data were subjected to statistical analysis. The surgery led to a significant improvement in ankle mobility. Radiological evaluation showed no signs of loosening or failure in the prosthetic components in any of the patients studied. Although the complication rate in our sample was high, it was equivalent to the rates found by other authors, and directly represents the learning curve associate with this kind of procedure. Four years after the procedure, it was found that the patients pain levels had significantly decreased, and that their functional patterns had significantly improved, with AOFAS and Hintermann scores indicating results that were excellent for 20%, good for 70% and poor for 10%. Treatment of ankle arthritis by means of total arthroplasty using the HINTEGRA prosthesis was capable of providing good results over an average observation period of four years.

[Questionnaire of the psychosocial profile of the patient with anophthalmia with indication of ocular prosthesis].

Science.gov (United States)

Nicodemo, Denise; Ferreira, Lydia Masako

2006-01-01

The patient with anophthalmia may present feelings of inferiority and rejection. Knowing his/her needs and expectations contribute to a better technical intervention. To elaborate a questionnaire of the psychosocial profile of the patient with anophthalmia with indication of ocular prosthesis. An exploratory research was used to elaborate the questionnaire, by means of a guided interview followed by writing down what was said by the interviewees, who were adult patients of the Bucco-Maxillo-Facial Prosthesis Center of FOSJC - UNESP. The guided interview was made up of 14 items directly related to the future outline of the profile. Each item of the interview resulted in questions of the questionnaire, which was pretested twice before reaching its final version. The patients reported, in the exploratory research, unpleasant feelings with the loss of the eye; relationship shyness; expectations regarding surgery and prosthesis use; a wish to receive explanations and to hold their opinion about the treatment. The questionnaire of the psychosocial profile of the patient with anophthalmia with indication of ocular prosthesis is, therefore, made of 43 questions divided into 5 blocks in order to aid the comprehension of the inquired aspects and to facilitate both the computation of data and discussion, and also to improve the selection of questions according to the objective of the researcher or professional. It was concluded that the questionnaire was viable, can be used in full or by selecting blocks and provide a panorama of the patient's history related to the problem he/she faces, from the loss of the ocular globe to the confection of the prosthesis.

Use of digital technologies for nasal prosthesis manufacturing.

Science.gov (United States)

Palousek, David; Rosicky, Jiri; Koutny, Daniel

2014-04-01

Digital technology is becoming more accessible for common use in medical applications; however, their expansion in prosthetic and orthotic laboratories is not large because of the persistent image of difficult applicability to real patients. This article aims to offer real example in the area of human facial prostheses. This article describes the utilization of optical digitization, computational modelling, rapid prototyping, mould fabrication and manufacturing of a nasal silicone prosthesis. This technical note defines the key points of the methodology and aspires to contribute to the introduction of a certified manufacturing procedure. The results show that the used technologies reduce the manufacturing time, reflect patient's requirements and allow the manufacture of high-quality prostheses for missing facial asymmetric parts. The methodology provides a good position for further development issues and is usable for clinical practice. Clinical relevance Utilization of digital technologies in facial prosthesis manufacturing process can be a good contribution for higher patient comfort and higher production efficiency but with higher initial investment and demands for experience with software tools.

Maxillary Implant-Supported Fixed Prosthesis: A Survey of Reviews and Key Variables for Treatment Planning.

Science.gov (United States)

Gallucci, German O; Avrampou, Marianna; Taylor, James C; Elpers, Julie; Thalji, Ghadeer; Cooper, Lyndon F

2016-01-01

This review was conducted to provide information to support the establishment of clinical guidelines for the treatment of maxillary edentulism using implant-supported fixed dental prostheses. Initial efforts were directed toward a systematic review with a defined PICO question: "For maxillary edentulous patients with dental implants treated using a fixed prosthesis, what is the impact of prosthesis design on prosthesis survival and complications?" Following a title search of more than 3,000 titles identified by electronic search of PubMed, 180 articles were identified that addressed the clinical evaluation of maxillary dental implant prostheses. The broad methodologic heterogeneity and clinical variation among reports precluded this approach for a systematic review. The information was extracted using a standardized extraction table by two pairs of investigators, and the reported outcomes were then summarized according to reported outcomes for implant prostheses supported by four, six, or eight implants using unitary or segmented prostheses. This review indicated that high prosthetic survival is observed using all approaches. The advantages of using fewer implants and a unitary prosthesis are revealed in the surgical phases, and complications commonly involve the fracture or detachment of acrylic teeth and reduced access for proper oral hygiene and related biologic complications. Using six implants typically involved grafting of posterior regions with advantages of reduced cantilevers and redundancy of implant support. Reduced prosthesis survival in these cases was associated with poor implant distribution. Segmented prostheses supported by six or more implants offered greater prosthetic survival, perhaps due to posterior implant placement. Advantages of a segmented prosthesis included pragmatic issues of accommodating divergent implants, attaining passive fit, combining prosthetic materials, and relative simplicity of repair. The existing literature demonstrated

HyPro: A Multi-DoF Hybrid-Powered Transradial Robotic Prosthesis

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C. L. Semasinghe

2018-01-01

Full Text Available This paper proposes a multi-DoF hybrid-powered transradial robotic prosthesis, named HyPro. The HyPro consists of two prosthetic units: hand and wrist that can achieve five grasping patterns such as power grasp, tip grasp, lateral grasp, hook grasp, and index point. It is an underactuated device with 15 degrees of freedom. A hybrid powering concept is proposed and implemented on hand unit of HyPro where the key focus is on restoration of grasp functions of biological hand. A novel underactuated mechanism is introduced to achieve the required hand preshaping for a given grasping pattern using electric power in the pregrasp stage and body power is used in grasp stage to execute the final grasping action with the selected fingers. Unlike existing hybrid prostheses where each of the joints is separately controlled by either electric or body power, the proposed prosthesis is capable of delivering grasping power in combination. The wrist unit of HyPro is designed and developed to achieve flexion-extension and supination-pronation using electric power. Experiments were carried out to evaluate the functionality and performance of the proposed hybrid-powered robotic prosthesis. The results verified the potential of HyPro to perform intended grasping patterns effectively and efficiently.

Frequent complications and severe bone loss associated with the repiphysis expandable distal femoral prosthesis.

Science.gov (United States)

Cipriano, Cara A; Gruzinova, Irina S; Frank, Rachel M; Gitelis, Steven; Virkus, Walter W

2015-03-01

The treatment of choice for distal femur malignancies in skeletally immature patients remains controversial. An expandable endoprosthesis device (Repiphysis Limb Salvage System; Wright Medical Technology, Arlington, TN, USA) allows for limb preservation and noninvasive lengthening but has been associated with significant complications; however, the extent and implications of bone loss associated with this implant have not been reported. Our goals were to report (1) the 2-year minimum clinical outcomes after placement of the Repiphysis expandable prosthesis for pediatric distal femur malignancies; (2) the complications associated with this prosthesis; (3) the failure rate of this prosthesis; and (4) the revision alternatives available for salvage procedures. Between 2002 and 2010, one surgeon (SG) treated all skeletally immature patients (mean age, 10.1 years; range, 4.7-13.6 years) with distal femoral osteosarcoma using a Repiphysis expandable prosthesis. Of the 12 patients who met these criteria, two were excluded for death from disease before 2 years, and mean followup for the remaining 10 was 72 months (range, 26-119 months). Medical records were retrospectively reviewed for complications and clinical outcomes, as assessed by the Musculoskeletal Tumor Society (MSTS) scoring system. Radiographs at final followup were reviewed for bone loss and analyzed by the two senior authors (SG, WWV) to determine reconstruction options available for future revisions. MSTS scores averaged 67%, and we observed 37 implant-related complications requiring a total of 15 reoperations. Six patients underwent implant revisions with aseptic loosening being the predominant mode of failure; ultimately, four of these were converted to adult modular oncology prostheses, and two underwent total femoral replacements. Bone loss in this series was severe in terms of femoral length, cortical thinning, and metadiaphyseal compromise, and most patients will not have sufficient bone stock to permit

An anthropomorphic transhumeral prosthesis socket developed based on an oscillometric pump and controlled by force-sensitive resistor pressure signals.

Science.gov (United States)

Razak, N A Abd; Gholizadeh, H; Hasnan, N; Osman, N A Abu; Fadzil, S S Mohd; Hashim, N A

2017-02-01

While considering the importance of the interface between amputees and prosthesis sockets, we study an anthropomorphic prosthesis socket whose size can be dynamically changed according to the requirements of the residual limb. First, we introduce the structure and function of the anthropomorphic prosthesis socket. Second, we study the dynamic model of the prosthesis system and analyze the dynamic characteristics of the prosthesis socket system, the inputs of an oscillometric pump, and the control mechanism of force-sensitive resistor (FSR) pressure signals. Experiments on 10 healthy subjects using the designed system yield an average detection result between 102 and 112 kPa for the FSR pressure sensor and 39 and 41 kPa for the oscillometric pump. Results show the function of the FSR pressure signal in maintaining the contact pressure between the sockets and the residual limb. The potential development of an auto-adjusted socket that uses an oscillometric pump system will provide prosthetic sockets with controllable contact pressure at the residual limb. Moreover, this development is an attractive research area for researchers involved in rehabilitation engineering, prosthetics, and orthotics.

Validation of the Narrowing Beam Walking Test in Lower Limb Prosthesis Users.

Science.gov (United States)

Sawers, Andrew; Hafner, Brian

2018-04-11

To evaluate the content, construct, and discriminant validity of the Narrowing Beam Walking Test (NBWT), a performance-based balance test for lower limb prosthesis users. Cross-sectional study. Research laboratory and prosthetics clinic. Unilateral transtibial and transfemoral prosthesis users (N=40). Not applicable. Content validity was examined by quantifying the percentage of participants receiving maximum or minimum scores (ie, ceiling and floor effects). Convergent construct validity was examined using correlations between participants' NBWT scores and scores or times on existing clinical balance tests regularly administered to lower limb prosthesis users. Known-groups construct validity was examined by comparing NBWT scores between groups of participants with different fall histories, amputation levels, amputation etiologies, and functional levels. Discriminant validity was evaluated by analyzing the area under each test's receiver operating characteristic (ROC) curve. No minimum or maximum scores were recorded on the NBWT. NBWT scores demonstrated strong correlations (ρ=.70‒.85) with scores/times on performance-based balance tests (timed Up and Go test, Four Square Step Test, and Berg Balance Scale) and a moderate correlation (ρ=.49) with the self-report Activities-specific Balance Confidence scale. NBWT performance was significantly lower among participants with a history of falls (P=.003), transfemoral amputation (P=.011), and a lower mobility level (P.50 (ie, chance). The results provide strong evidence of content, construct, and discriminant validity for the NBWT as a performance-based test of balance ability. The evidence supports its use to assess balance impairments and fall risk in unilateral transtibial and transfemoral prosthesis users. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

The Effect of Breast Reconstruction Prosthesis on Photon Dose Distribution in Breast Cancer Radiotherapy

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fatemeh sari

2017-12-01

Full Text Available Introduction: Siliconeprosthetic implants are commonlyutilizedfor tissue replacement and breast augmentation after mastectomy. On the other hand, some patients require adjuvant radiotherapy in order to preventlocal-regional recurrence and increment ofthe overall survival. In case of recurrence, the radiation oncologist might have to irradiate the prosthesis.The aim of this study was to evaluate the effect of silicone prosthesis on photon dose distribution in breast radiotherapy. Materials and Methods: The experimental dosimetry was performed using theprosthetic breast phantom and the female-equivalent mathematical chest phantom. A Computerized Tomographybased treatment planning was performedusing a phantom and by CorePlan Treatment Planning System (TPS. For measuring the absorbed dose, thermoluminescent dosimeter(TLD chips (GR-207A were used. Multiple irradiations were completed for all the TLD positions, and the dose absorbed by the TLDs was read by a lighttelemetry (LTM reader. Results: Statistical comparisons were performed between the absorbed dosesassessed by the TLDs and the TPS calculations forthe same sites. Our initial resultsdemonstratedanacceptable agreement (P=0.064 between the treatment planning data and the measurements. The mean difference between the TPS and TLD resultswas 1.99%.The obtained findings showed that radiotherapy is compatible withsilicone gel prosthesis. Conclusion: It could be concludedthat the siliconbreast prosthesis has no clinicallysignificant effectondistribution of a 6 MV photon beam for reconstructed breasts.

Simulation of the filtration mechanism of hyaluronic acid in total knee prosthesis

International Nuclear Information System (INIS)

Paolo, J Di; Berli, M E; Campana, D M; Ubal, S; Cardenes, L D

2007-01-01

Polyethylene (UHMWPE) wear in current knee prosthesis causes prosthesis loosening after no more than 15 years. In this work, a steady state one-dimensional lubrication model with non- Newtonian fluid, porous elastic layer on tibial component, ultra-filtration mechanism of fluid and some features of the surface roughness is studied through a numerical technique based on the Finite Element Method. The results show that the UHMWPE stiffness makes difficult the lubrication mechanism of the artificial joint and promotes abrasive and fatigue wear. Nevertheless, the use of compliant porous materials on the tibial component could reduce friction and wear. Moreover, the ultra-filtration mechanism promotes efficiency on the joint

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users

Directory of Open Access Journals (Sweden)

Andrew Sawers

2018-03-01

Full Text Available Objective: Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Design: Cross-sectional. Participants: Unilateral lower-limb prosthesis users. Methods: Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalized distance walked. Heuristic rules were applied to determine whether the narrowing beam task was “too easy,” “too hard,” or “appropriately challenging” for each participant. Linear regression and Bland-Altman plots were used to determine whether combinations of the first 5 trials could predict participants’ stable beam-walking performance. Results: Forty unilateral lower-limb prosthesis users participated. Narrowing beam-walking was appropriately challenging for 98% of participants. Performance stabilized for 93% of participants within 5 trials, while 62% were stable across all trials. The mean of trials 3–5 accurately predicted stable performance. Conclusion: A clinical narrowing beam-walking test is likely to challenge a range of lower-limb prosthesis users, have minimal administrative burden, and exhibit no floor or ceiling effects. Narrowing beam-walking is therefore a clinically viable method to evaluate lower-limb prosthesis users’ balance ability, but requires psychometric testing before it is used to assess fall risk.

Inflatable penile prosthesis implant length with baseline characteristic correlations: preliminary analysis of the PROPPER study.

Science.gov (United States)

Bennett, Nelson; Henry, Gerard; Karpman, Edward; Brant, William; Jones, LeRoy; Khera, Mohit; Kohler, Tobias; Christine, Brian; Rhee, Eugene; Kansas, Bryan; Bella, Anthony J

2017-12-01

"Prospective Registry of Outcomes with Penile Prosthesis for Erectile Restoration" (PROPPER) is a large, multi-institutional, prospective clinical study to collect, analyze, and report real-world outcomes for men implanted with penile prosthetic devices. We prospectively correlated co-morbid conditions and demographic data with implanted penile prosthesis size to enable clinicians to better predict implanted penis size following penile implantation. We present many new data points for the first time in the literature and postulate that radical prostatectomy (RP) is negatively correlated with penile corporal length. Patient demographics, medical history, baseline characteristics and surgical details were compiled prospectively. Pearson correlation coefficient was generated for the correlation between demographic, etiology of ED, duration of ED, co-morbid conditions, pre-operative penile length (flaccid and stretched) and length of implanted penile prosthesis. Multivariate analysis was performed to define predictors of implanted prosthesis length. From June 2011 to June 2017, 1,135 men underwent primary implantation of penile prosthesis at a total of 11 study sites. Malleable (Spectra), 2-piece Ambicor, and 3-piece AMS 700 CX/LGX were included in the analysis. The most common patient comorbidities were CV disease (26.1%), DM (11.1%), and PD (12.4%). Primary etiology of ED: RP (27.4%), DM (20.3%), CVD (18.0%), PD (10.3%), and Priapism (1.4%), others (22.6%). Mean duration of ED is 6.2¡À4.1 years. Implant length was weakly negatively correlated with White/Caucasian (r=-0.18; Pprosthesis length is negatively correlated with some ethnic groups, prostatectomy, and incontinence. Positive correlates include CV disease, preoperative stretched penile length, and flaccid penile length.

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease.

Science.gov (United States)

van Slooten, Ymkje J; van Melle, Joost P; Freling, Hendrik G; Bouma, Berto J; van Dijk, Arie Pj; Jongbloed, Monique Rm; Post, Martijn C; Sieswerda, Gertjan T; Huis In 't Veld, Anna; Ebels, Tjark; Voors, Adriaan A; Pieper, Petronella G

2016-01-01

To report the prevalence of aortic valve prosthesis-patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis later in life. However, the prevalence and clinical consequences of aortic PPM in ACHD are presently unknown. From the national Dutch Congenital Corvitia (CONCOR) registry, we identified 207 ACHD with an aortic valve prosthesis for this cross-sectional cohort study. Severe PPM was defined as an indexed effective orifice area ≤0.65 cm2/m2 and moderate PPM as an indexed orifice area ≤0.85 cm2/m2 measured using echocardiography. Exercise capacity was reported as percentage of predicted exercise capacity (PPEC). Of the 207 patients, 68% was male, 71% had a mechanical prosthesis and mean age at inclusion was 43.9 years ±11.4. The prevalence of PPM was 42%, comprising 23% severe PPM and 19% moderate PPM. Prevalence of PPM was higher in patients with mechanical prostheses (pHeart Association (NYHA) class remained stable in most patients. PPM showed no significant effect on death or hospitalisation during follow-up (p=0.218). In this study we report a high prevalence (42%) of PPM in ACHD with an aortic valve prosthesis and an independent association of PPM with diminished exercise capacity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Customized Knee Prosthesis in Treatment of Giant Cell Tumors of the Proximal Tibia: Application of 3-Dimensional Printing Technology in Surgical Design.

Science.gov (United States)

Luo, Wenbin; Huang, Lanfeng; Liu, He; Qu, Wenrui; Zhao, Xin; Wang, Chenyu; Li, Chen; Yu, Tao; Han, Qing; Wang, Jincheng; Qin, Yanguo

2017-04-07

BACKGROUND We explored the application of 3-dimensional (3D) printing technology in treating giant cell tumors (GCT) of the proximal tibia. A tibia block was designed and produced through 3D printing technology. We expected that this 3D-printed block would fill the bone defect after en-bloc resection. Importantly, the block, combined with a standard knee joint prosthesis, provided attachments for collateral ligaments of the knee, which can maintain knee stability. MATERIAL AND METHODS A computed tomography (CT) scan was taken of both knee joints in 4 patients with GCT of the proximal tibia. We developed a novel technique - the real-size 3D-printed proximal tibia model - to design preoperative treatment plans. Hence, with the application of 3D printing technology, a customized proximal tibia block could be designed for each patient individually, which fixed the bone defect, combined with standard knee prosthesis. RESULTS In all 4 cases, the 3D-printed block fitted the bone defect precisely. The motion range of the affected knee was 90 degrees on average, and the soft tissue balance and stability of the knee were good. After an average 7-month follow-up, the MSTS score was 19 on average. No sign of prosthesis fracture, loosening, or other relevant complications were detected. CONCLUSIONS This technique can be used to treat GCT of the proximal tibia when it is hard to achieve soft tissue balance after tumor resection. 3D printing technology simplified the design and manufacturing progress of custom-made orthopedic medical instruments. This new surgical technique could be much more widely applied because of 3D printing technology.

Cyclooxygenase-2 inhibitors and knee prosthesis surgery

OpenAIRE

Meunier, Andreas

2008-01-01

Adverse effects of cyclooxygenase (COX) inhibitors on bone healing have previously been demonstrated in diaphyseal fracture models in animals. In spite of that, they are widely used as postoperative analgesics in orthopaedic surgery. After joint replacement, a bone repair process starts at the interface between bone and cement. If this process is disturbed, the prosthesis may never become rigidly fixed to the bone, leading to migration and with time loosening. This thesis investigates the eff...

[Directions for reoperation of patients with Björk-Shiley convexo-concave valve prosthesis, based on long-term experience].

Science.gov (United States)

Yamaki, F; Nakano, K; Endo, M; Hashimoto, A; Koyanagi, H

1994-02-01

Although a high incidence of strut fracture of the Björk-Shiley convexo-concave (C-C) valve prosthesis has been reported, it is still controversial whether the prosthesis functioning normally should be replaced electively. To clarify our policy for this issue, we reviewed 28 patients who had undergone mitral valve replacement with a C-C valve prosthesis, and evaluated long-term results according to STS guidelines. The incidence of valve-related complications expressed as % patient-year were; structural deterioration 0.30, nonstructural dysfunction 0.30, thromboembolism 1.20. There were no thrombosed valves, anticoagulant-related hemorrhage or prosthetic valve endocarditis. The actuarial free rate after valve replacement with the C-C at 10 years, constructed by the Kaplan-Meier method, were compared with those with St. Jude Medical (SJM) valve prosthesis. (1) Actuarial survival: 77.9 vs 87.3 (NS), (2) Reoperation-free: 91.6 vs 98.0 (p valve-related complications: 71.2 vs 77.7 (NS). The long-term results with the C-C were compatible to those with a SJM valve prosthesis. However, if a strut fracture occurs, it is very difficult to save the patient's life. The hospital mortality of re-replacement of valve prosthesis during the last 10 years, at our institute, was 2.6%, which is almost equal to the cumulative risk of strut fracture of the C-C valve after 10 years (3.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Above-knee prosthesis design based on fatigue life using finite element method and design of experiment.

Science.gov (United States)

Phanphet, Suwattanarwong; Dechjarern, Surangsee; Jomjanyong, Sermkiat

2017-05-01

The main objective of this work is to improve the standard of the existing design of knee prosthesis developed by Thailand's Prostheses Foundation of Her Royal Highness The Princess Mother. The experimental structural tests, based on the ISO 10328, of the existing design showed that a few components failed due to fatigue under normal cyclic loading below the required number of cycles. The finite element (FE) simulations of structural tests on the knee prosthesis were carried out. Fatigue life predictions of knee component materials were modeled based on the Morrow's approach. The fatigue life prediction based on the FE model result was validated with the corresponding structural test and the results agreed well. The new designs of the failed components were studied using the design of experimental approach and finite element analysis of the ISO 10328 structural test of knee prostheses under two separated loading cases. Under ultimate loading, knee prosthesis peak von Mises stress must be less than the yield strength of knee component's material and the total knee deflection must be lower than 2.5mm. The fatigue life prediction of all knee components must be higher than 3,000,000 cycles under normal cyclic loading. The design parameters are the thickness of joint bars, the diameter of lower connector and the thickness of absorber-stopper. The optimized knee prosthesis design meeting all the requirements was recommended. Experimental ISO 10328 structural test of the fabricated knee prosthesis based on the optimized design confirmed the finite element prediction. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

A Preliminary Report on Combined Penoscrotal and Perineal Approach for Placement of Penile Prosthesis with Corporal Fibrosis

Directory of Open Access Journals (Sweden)

John P. Brusky

2008-01-01

Full Text Available Purpose. This paper aims at describing the combined penoscrotal and perineal approach for placement of penile prosthesis in cases of severe corporal fibrosis and scarring. Materials and methods. Three patients with extensive corporal fibrosis underwent penile prosthesis placement via combined penoscrotal and perineal approach from 1997 to 2006. Follow-up ranged from 15 to 129 months. Results. All patients underwent successful implantation of semirigid penile prosthesis. There were no short- or long-term complications. Conclusions. Results on combined penoscrotal and perineal approach to penile prosthetic surgery in this preliminary series of patients suggest that it is a safe technique and increases the chance of successful outcome in the surgical management of severe corporal fibrosis.

Functional evaluation of a CAD/CAM prosthesis for immediate defect repair after total maxillectomy: a case series of 18 patients with maxillary sinus cancer.

Science.gov (United States)

Jiang, Fei-Fei; Hou, Yan; Lu, Li; Ding, Xiao-Xu; Li, Wei; Yan, Ai-Hui

2015-01-01

To evaluate the facial profiles and functional recovery of 18 patients treated by a computer-aided designed/manufactured hollow obturator prosthesis (CAD/CAM prosthesis) after total maxillectomy for malignant maxillary sinus tumor. A retrospective observational study was performed to evaluate the facial profiles and functional recovery of 18 patients with T3-4a N0 M0 maxillary sinus cancer, who were treated by total maxillectomy and simultaneous implantation of a computer-aided designed/manufactured hollow obturator prosthesis (CAD/CAM prosthesis). Follow-ups were performed 1, 3, 6, and 12 months after surgery. Facial measurements, speech intelligibility, and chewing and swallowing functions were examined. Thirteen patients converted to a permanent prosthesis 6 months after surgery. Comparisons were made between patients with and without the CAD/CAM or permanent prosthesis at various times using SPSS13.0 statistical software (SPSS Inc., Chicago, IL, USA). Speech intelligibility, facial depression, and eyeball prolapse results showed improvements with prosthesis use at 1, 3, and 6 months after surgery (p maxillectomy. This surgical treatment of maxillary sinus cancer is applied rarely in China, but it has a good effect based on our observation. Simultaneous CAD/CAM prosthesis implantation after total maxillectomy can recover the facial profile, enhance the speaking, swallowing, and chewing functions, and improve the quality of life of patients. Tumor recurrence can be detected by direct observation of the postoperative maxillary cavity. This technique avoids the need for dental implants because the bottom part of the prosthesis contains a palatal plate with dentures. © 2014 Wiley Periodicals, Inc.

Veno-arterial extracorporeal membrane oxygenation as a bridge for enabling surgery in a patient under cardiogenic shock due to acute mitral prosthesis dysfunction

Directory of Open Access Journals (Sweden)

María Elena Arnáiz-García

2018-04-01

Full Text Available A 52-year-old male patient, who underwent mitral replacement with a mechanical prosthesis as a child, sustained a cardiac arrest which was successfully resuscitated. Further investigation showed prosthesis malfunction with significant regurgitation in the context of multi-organ failure. In such a life-threatening condition, veno-arterial extracorporeal membrane oxygenation was considered as a rescue procedure to achieve optimisation of clinical status to allow definitive surgical treatment. An unusual complete fracture of the prosthesis was subsequently identified as the cause of acute dysfunction. Keywords: VA-ECMO, Mitral, Prosthesis, Dysfunction, Cardiogenic shock

Percutaneous closure of ductus arteriosus with the amplatzer prosthesis. The Brazilian experience

Directory of Open Access Journals (Sweden)

Luiz Carlos Simões

2001-12-01

Full Text Available OBJECTIVE - To report the results of percutaneous occlusion of persistent ductus arteriosus with the Amplatzer prosthesis in 2 Brazilian cardiological centers. METHODS - From May 1998 to July 2000, 33 patients with clinical and laboratory diagnosis of persistent ductus arteriosus underwent attempts at percutaneous implantation of the Amplatzer prosthesis. The median age was 36 months (from 6 months to 38 years, and the median weight was 14kg (from 6 to 92kg. Sixteen patients (48.5% were under 2 years of age at the time of the procedure. All patients were followed up with periodical clinical and echocardiographic evaluations to assess the presence and degree of residual shunt and possible complications, such as pseudocoarctation of the aorta and left pulmonary artery stenosis. RESULTS - The minimum diameter of the arterial ducts ranged from 2.5 to 7.0mm (mean of 4.0±1.0, median of 3.9. The rate of success for implantation of the prosthesis was 100%. Femoral pulse was lost in 1 patient. The echocardiogram revealed total closure prior to hospital discharge in 30 patients, and in the follow-up visit 3 months later in the 3 remaining patients. The mean follow-up duration was 6.4±3.4 months. All patients were clinically well, asymptomatic, and did not need medication. No patient had narrowing of the left pulmonary artery or of the aorta. No early or late embolic events occurred, nor did infectious endarteritis. A new hospital admission was not required for any patient. CONCLUSION - The Amplatzer prosthesis for persistent ductus arteriosus is safe and highly effective for occlusion of ductus arteriosus of varied diameters, including large ones in small symptomatic infants.

Rehabilitation with ear prosthesis linked to osseointegrated implants.

Science.gov (United States)

Goiato, Marcelo C; dos Santos, Daniela M; Haddad, Marcela F; Moreno, Amália

2012-06-01

The absence of an ear, which can be the result of a congenital malformation, surgical tumour resection or traumatic injury, is a significant aesthetic problem. Attachment of ear prostheses with adhesives can cause local irritation for the wearer and affect the colour of the prostheses. Use of implants in craniofacial reconstruction can improve the retention and stability of prostheses giving to patient greater comfort and security relative to adhesive attachment. The aim of this report was to present a clinical case of a mutilated patient who was rehabilitated by means of installing an ear prosthesis fixed through osseointegrated implants. The patient had two implants installed in the mastoid region that were linked by a bar, and a clip-type system was used. The ear prosthesis was constructed from medical-use silicone, pigmented to match the patient's skin colour and linked to the retention system. The patient's rehabilitation was satisfactory from both a functional and an aesthetic point of view, making it possible for the patient to return to a normal social life and regain lost self-esteem. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

Hearing improvement after stapedotomy using teflon loop prosthesis

International Nuclear Information System (INIS)

Ahmed, S.; Raza, N.

2006-01-01

To assess hearing improvement after stapedotomy for otosclerosis using teflon loop prosthesis. Thirty diagnosed cases of otosclerosis were included in the study. Ear with greater air-bone gap was selected and stapedotomy was done using teflon loop prosthesis (size 4 - 4.5 mm). Mild vertigo occurred during immediate postoperative period, which subsided with Inj. Prochlorperazine. Patients were followed-up postsurgically at one month, two months, four months, six months and one year and postoperative air-bone gap was calculated. Out of 30 cases, there were 24 males and 06 females. The age ranged from 18 to 50 years. Twenty-one (70%) patients had bilateral hearing loss and 09 (30%) had tinnitis also. Pre-operative audiograms showed conductive deafness. Carhart's notch was present in 10 (33.3%) cases. Tympanogram revealed loss of stapedial reflex. Postoperatively good hearing improvement was seen in 56.7% (postoperative air-bone gap closure upto 10 dB), fair improvement in 30% (postoperative air bone gap closure from 11 to 20 dB) and poor results in 10% (postoperative air-bone gap more than 21 dB) cases. One patient developed dead ear. (author)

The clinical relevance of advanced artificial feedback in the control of a multi-functional myoelectric prosthesis

DEFF Research Database (Denmark)

Markovic, Marko; Schweisfurth, Meike A.; Engels, Leonard F.

2018-01-01

. Nonetheless, the benefits of feedback in prosthetics are still debated. The lack of consensus is likely due to the complex nature of sensory feedback during prosthesis control, so that its effectiveness depends on multiple factors (e.g., task complexity, user learning). METHODS: We evaluated the impact...... of these factors with a longitudinal assessment in six amputee subjects, using a clinical setup (socket, embedded control) and a range of tasks (box and blocks, block turn, clothespin and cups relocation). To provide feedback, we have proposed a novel vibrotactile stimulation scheme capable of transmitting...... multiple variables from a multifunction prosthesis. The subjects wore a bracelet with four by two uniformly placed vibro-tactors providing information on contact, prosthesis state (active function), and grasping force. The subjects also completed a questionnaire for the subjective evaluation...

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature

Directory of Open Access Journals (Sweden)

Ernesto Suaste-Gómez

2016-03-01

Full Text Available An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa and temperature (2 °C to 90 °C. The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing. More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception.

Multi-body simulation of various falling scenarios for determining resulting loads at the prosthesis interface of transfemoral amputees with osseointegrated fixation.

Science.gov (United States)

Welke, Bastian; Schwarze, Michael; Hurschler, Christof; Calliess, Tilman; Seehaus, Frank

2013-07-01

Conventionally, transfemoral amputees are treated with a shaft prosthesis fitted over the residual limb. To improve the quality of life of such patients, in particular those with complications relating to conventional attachment (e.g., skin irritation, stump ulcers, and poor motor-control with short stumps), osseointegrated prosthesis fixation implants have been developed and implanted in a limited population of patients. To assess possible damage to the implant/prosthesis during falling scenarios, the loads in high-risk situations were estimated using a multi-body simulation of motion. Five falling scenarios were identified and performed by healthy volunteer wearing safety equipment. Kinematic data and ground reaction forces were captured as input for the inverse-dynamics-based simulations, from which the forces and moments at a typical implant-prosthesis interface location were computed. The estimated peak loads in all five scenarios were of a magnitude that could lead to bone fracture. The largest peak force observed was 3274 ± 519 N, with an associated resultant moment of 176 ± 55 Nm on the prosthesis-implant interface. A typical femur is prone to fracture under this load, thus illustrating the need for a safety-release element in osseointegrated prosthesis fixation. Copyright © 2013 Orthopaedic Research Society.

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature.

Science.gov (United States)

Suaste-Gómez, Ernesto; Rodríguez-Roldán, Grissel; Reyes-Cruz, Héctor; Terán-Jiménez, Omar

2016-03-04

An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF) for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa) and temperature (2 °C to 90 °C). The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing). More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception.

Prosthesis use in adult acquired major upper-limb amputees: patterns of wear, prosthetic skills and the actual use of prostheses in activities of daily life.

Science.gov (United States)

Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-11-01

To describe patterns of prosthesis wear and perceived prosthetic usefulness in adult acquired upper-limb amputees (ULAs). To describe prosthetic skills in activities of daily life (ADL) and the actual use of prostheses in the performance of ADL tasks. To estimate the influence of prosthetic skills on actual prosthesis use and the influence of background factors on prosthetic skills and actual prosthesis use. Cross-sectional study analysing population-based questionnaire data (n = 224) and data from interviews and clinical testing in a referred/convenience sample of prosthesis-wearing ULAs (n = 50). Effects were analysed using linear regression. 80.8% wore prostheses. 90.3% reported their most worn prosthesis as useful. Prosthetic usefulness profiles varied with prosthetic type. Despite demonstrating good prosthetic skills, the amputees reported actual prosthesis use in only about half of the ADL tasks performed in everyday life. In unilateral amputees, increased actual use was associated with sufficient prosthetic training and with the use of myoelectric vs cosmetic prostheses, regardless of amputation level. Prosthetic skills did not affect actual prosthesis use. No background factors showed significant effect on prosthetic skills. Most major ULAs wear prostheses. Individualised prosthetic training and fitting of myoelectric rather than passive prostheses may increase actual prosthesis use in ADL.

Verge of Collapse: The Pros/thesis of Art Research

Science.gov (United States)

Garoian, Charles R.

2008-01-01

This article explores "prosthesis" as a metaphor of embodiment in art-based research to challenge the utopian myth of wholeness and normality in art and the human body. Bearing in mind the correspondences between amputated bodies and the cultural dislocations of art, I propose "prosthetic epistemology" and "prosthetic ontology" as embodied knowing…

Prosthetic Rehabilitation of a Patient with Ocular Defect using Semi-customized Prosthesis: A Case Report

OpenAIRE

Putanikar, Nagaraj Y.; Patil, Anandkumar G.; Shetty, Pavithra K.; Nagaral, Suresh; Mithaiwala, Hatimali I.

2015-01-01

Severe physical and psychological distress occurs due to disfigurement caused by loss of eye. Ocular prosthesis is the only mode of rehabilitation for the missing eye. There are different materials and techniques used for the fabrication of the same. Resin proved to be the better among the available materials. Either using the stock eye or using customized ocular prosthesis has their own advantages and disadvantages. Through our clinical report, we have fabricated a semi-customized ocular pro...

SU-E-J-230: Effect of Metal Hip Prosthesis On the Accuracy of Electromagnetic Localization and Tracking

International Nuclear Information System (INIS)

Butler, W; Merrick, G; Kurko, B; Bittner, N

2014-01-01

Purpose: To quantify the effect of metal hip prosthesis on the ability to track and localize electromagnetic transponders. Methods: Three Calypso transponders were implanted into two prostate phantoms. The geometric center of the transponders were identified on computed tomography and set as the isocenter. With the phantom stationary on the treatment table and the tracking array 14-cm above the isocenter, data was acquired by the Calypso system at 10 Hz to establish the uncertainty in measurements. Transponder positional data was acquired with unilateral hip prostheses of different metallic compositions and then with bilateral hips placed at variable separation from the phantom. Results: Regardless of hip prosthesis composition, the average vector displacement in the presence of a unilateral prosthesis was < 0.5 mm. The greatest contribution to overall vector displacement occurred in the lateral dimension. With bilateral hip prosthesis, the average vector displacement was 0.3 mm. The displacement in the lateral dimension was markedly reduced compared with a unilateral hip, suggesting that there was a countervailing effect with bilateral hip prosthesis. The greatest average vector displacement was 0.6 mm and occurred when bilateral hip prostheses were placed within 4 cm of the detector array. Conclusion: Unilateral and bilateral hip prostheses did not have any meaningful effect on the ability to accurately track electromagnetic transponders implanted in a prostate phantom. At clinically realistic distances between the hip and detection array, the average tracking error is negligible

Control of dental prosthesis system with microcontroller.

Science.gov (United States)

Kapidere, M; Müldür, S; Güler, I

2000-04-01

In this study, a microcontroller-based electronic circuit was designed and implemented for dental prosthesis curing system. Heater, compressor and valve were controlled by 8-bit PIC16C64 microcontroller which is programmed using MPASM package. The temperature and time were controlled automatically by preset values which were inputted from keyboard while the pressure was kept constant. Calibration was controlled and the working range was tested. The test results showed that the system provided a good performance.

Prosthesis-patient mismatch after transcatheter aortic valve implantation using the Edwards SAPIEN™ prosthesis.

Science.gov (United States)

Van Linden, Arnaud; Kempfert, Jörg; Blumenstein, Johannes; Rastan, Ardawan; Holzhey, David; Lehmann, Sven; Mohr, Friedrich W; Walther, Thomas

2013-08-01

Prosthesis-patient mismatch (PPM) is defined as a too small effective orifice area (EOA) of the prosthetic valve in relation to the patient's body size and has been documented to be related to adverse outcomes after conventional aortic valve replacement (AVR). Aim of this study was to analyze the incidence of PPM after transcatheter aortic valve implantation (T-AVI) using the Edwards SAPIEN prosthesis and its relation to postoperative outcome. 200 consecutive high-risk patients underwent transapical aortic valve implantation (TA-AVI) between February 2006 and January 2009 and fulfilled 1 year follow-up were included. Severe PPM was defined as indexed EOA (EOAi) <0.65 cm2/m2 and moderate PPM as EOAi = 0.65-0.85 cm2/m2, EOA was calculated from transthoracic echocardiographic (TTE) measurements using the continuity equation. Total 112 patients with sufficient postoperative TTE image quality formed the study group. EOAi increased from 0.3 ± 0.1 cm2/m2 (preoperatively) to 1.1 ± 0.4 cm2/m2 after TA-AVI (p < 0.001). According to the standard definitions, PPM was seen in 38.4% of the patients and 9.8% presented with severe PPM. The occurrence of PPM had neither an effect on clinical outcome in terms of NYHA class nor on survival. Patients with PPM had significantly higher postoperative transprosthetic gradients (mean gradient 10.4 ± 4.1 versus 7.1 ± 3.0 mm Hg, p < 0.001). Based on the in vitro EOA data obtained from pulse duplicator measurements, however, none of the patients was judged to have PPM. Transcatheter AVI provides good antegrade hemodynamic function and EOAi improves significantly. According to standardized evaluations PPM occurs after TA-AVI, but it is not associated with adverse outcomes. Thus use of the continuity equation may not adequately reflect the situation after T-AVI or the current definition of PPM is not suitable for T-AVI prostheses. Georg Thieme Verlag KG Stuttgart · New York.

A novel speech prosthesis for mandibular guidance therapy in hemimandibulectomy patient: A clinical report

Directory of Open Access Journals (Sweden)

Raghavendra Adaki

2016-01-01

Full Text Available Treating diverse maxillofacial patients poses a challenge to the maxillofacial prosthodontist. Rehabilitation of hemimandibulectomy patients must aim at restoring mastication and other functions such as intelligible speech, swallowing, and esthetics. Prosthetic methods such as palatal ramp and mandibular guiding flange reposition the deviated mandible. Such prosthesis can also be used to restore speech in case of patients with debilitating speech following surgical resection. This clinical report gives detail of a hemimandibulectomy patient provided with an interim removable dental speech prosthesis with composite resin flange for mandibular guidance therapy.

In vivo operation of the Boston 15-channel wireless subretinal visual prosthesis

Science.gov (United States)

Shire, Douglas B.; Doyle, Patrick; Kelly, Shawn K.; Gingerich, Marcus D.; Chen, Jinghua; Cogan, Stuart F.; Drohan, William A.; Mendoza, Oscar; Theogarajan, Luke; Wyatt, John; Rizzo, Joseph F.

2010-02-01

This presentation concerns the engineering development of the Boston visual prosthesis for restoring useful vision to patients blind with degenerative retinal disease. A miniaturized, hermetically-encased, 15-channel wirelessly-operated retinal prosthetic was developed for implantation and pre-clinical studies in Yucatan mini-pig animal models. The prosthesis conforms to the eye and drives a microfabricated polyimide stimulating electrode array having sputtered iridium oxide electrodes. This array is implanted into the subretinal space using a specially-designed ab externo surgical technique; the bulk of the prosthesis is on the surface of the sclera. The implanted device includes a hermetic titanium case containing a 15-channel stimulator chip; secondary power/data receiving coils surround the cornea. Long-term in vitro pulse testing was also performed on the electrodes to ensure their stability over years of operation. Assemblies were first tested in vitro to verify wireless operation of the system in biological saline using a custom RF transmitter circuit and primary coils. Stimulation pulse strength, duration and frequency were programmed wirelessly using a computer with a custom graphical user interface. Operation of the retinal implant was verified in vivo in 3 minipigs for more than three months by measuring stimulus artifacts on the eye surface using contact lens electrodes.

Reliability of MRI findings in candidates for lumbar disc prosthesis

International Nuclear Information System (INIS)

Berg, Linda; Espeland, Ansgar; Neckelmann, Gesche; Gjertsen, Oeivind; Hellum, Christian; Johnsen, Lars G.; Eide, Geir E.

2012-01-01

Limited reliability data exist for localised magnetic resonance imaging (MRI) findings relevant to planning of treatment with lumbar disc prosthesis and later outcomes. We assessed the reliability of such findings in chronic low back pain patients who were accepted candidates for disc prosthesis. On pretreatment MRI of 170 patients (mean age 41 years; 88 women), three experienced radiologists independently rated Modic changes, disc findings and facet arthropathy at L3/L4, L4/L5 and L5/S1. Two radiologists rerated 126 examinations. For each MRI finding at each disc level, agreement was analysed using the kappa statistic and differences in prevalence across observers using a fixed effects model. All findings at L3/L4 and facet arthropathy at L5/S1 had a mean prevalence <10% across observers and were not further analysed, ensuring interpretable kappa values. Overall interobserver agreement was generally moderate or good (kappa 0.40-0.77) at L4-S1 for Modic changes, nucleus pulposus signal, disc height (subjective and measured), posterior high-intensity zone (HIZ) and disc contour, and fair (kappa 0.24) at L4/L5 for facet arthropathy. Posterior HIZ at L5/S1 and severely reduced subjective disc height at L4/L5 differed up to threefold in prevalence between observers (p < 0.0001). Intraobserver agreement was mostly good or very good (kappa 0.60-1.00). In candidates for disc prosthesis, mostly moderate interobserver agreement is expected for localised MRI findings. (orig.)

Reliability of MRI findings in candidates for lumbar disc prosthesis

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Berg, Linda; Espeland, Ansgar [Haukeland University Hospital, Department of Radiology, Bergen (Norway); University of Bergen, Section for Radiology, Department of Surgical Sciences, Bergen (Norway); Neckelmann, Gesche [Haukeland University Hospital, Department of Radiology, Bergen (Norway); Gjertsen, Oeivind [Oslo University Hospital, Department of Neuroradiology, Oslo (Norway); Hellum, Christian [Oslo University Hospital, Department of Orthopaedics, Oslo (Norway); University of Oslo, Department of Orthopaedics, Oslo (Norway); Johnsen, Lars G. [University Hospital of Trondheim, National Centre for Diseases of the Spine, Trondheim (Norway); University Hospital of Trondheim, Orthopaedic Department, Trondheim (Norway); Eide, Geir E. [Haukeland University Hospital, Centre for Clinical Research, Bergen (Norway); University of Bergen, Department of Public Health and Primary Health Care, Bergen (Norway)

2012-07-15

Limited reliability data exist for localised magnetic resonance imaging (MRI) findings relevant to planning of treatment with lumbar disc prosthesis and later outcomes. We assessed the reliability of such findings in chronic low back pain patients who were accepted candidates for disc prosthesis. On pretreatment MRI of 170 patients (mean age 41 years; 88 women), three experienced radiologists independently rated Modic changes, disc findings and facet arthropathy at L3/L4, L4/L5 and L5/S1. Two radiologists rerated 126 examinations. For each MRI finding at each disc level, agreement was analysed using the kappa statistic and differences in prevalence across observers using a fixed effects model. All findings at L3/L4 and facet arthropathy at L5/S1 had a mean prevalence <10% across observers and were not further analysed, ensuring interpretable kappa values. Overall interobserver agreement was generally moderate or good (kappa 0.40-0.77) at L4-S1 for Modic changes, nucleus pulposus signal, disc height (subjective and measured), posterior high-intensity zone (HIZ) and disc contour, and fair (kappa 0.24) at L4/L5 for facet arthropathy. Posterior HIZ at L5/S1 and severely reduced subjective disc height at L4/L5 differed up to threefold in prevalence between observers (p < 0.0001). Intraobserver agreement was mostly good or very good (kappa 0.60-1.00). In candidates for disc prosthesis, mostly moderate interobserver agreement is expected for localised MRI findings. (orig.)

[Mid-term effectiveness of total hip arthroplasty with collum femoris preserving prosthesis].

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Li, Mingqing; Hu, Yihe; Li, Kanghua; Liao, Qiande; Wen, Ting; Zhong, Da

2012-08-01

To discuss the clinical application of total hip arthroplasty (THA) with collum femoris preserving (CFP) prosthesis and to analyze the mid-term effectiveness. Between January 2004 and February 2007, 45 patients (48 hips) underwent THA with CFP prosthesis. There were 29 males (31 hips) and 16 females (17 hips) with an average age of 48.8 years (range, 38-60 years), including 20 left hips, 22 right hips, and 3 bilateral hips. The causes of hip replacement were osteoarthritis (20 cases), avascular necrosis of femoral head (13 cases), dysplasia (4 cases), rheumatoid arthritis (3 cases), posttraumatic osteoarthritis (2 cases), ankylosing spondylitis (2 cases), and Perths disease (1 case). The average disease duration was 6.1 years (range, 2-13 years). Harris scores, visual analogue scale (VAS) score, and the hip range of motion (ROM) were recorded at pre- and post-operation. The X-ray films were taken at pre- and post-operation to observe the position, loosening of the prosthesis, and ectopic ossification. The gait of patients were also evaluated during follow-up. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients. All 45 patients were followed up 5-8 years with an average of 6.4 years. All the incisions healed by first intention. No infection, hip dislocation, nerve injury, or deep vein thrombosis occurred. Six cleavage fractures (13.3%) of the lateral femoral diaphysis at the distal prosthesis occurred during operation, which healed at 8 months postoperatively without any treatment. Mild ectopic ossification occurred in 4 patients (8.9%) who had no discomfort. Five patients (11.1%) had bone mineral density loss in the region of the proximal femur. The survival rates of the cups and stems were all 100% at last follow-up. The results of Harris score, VAS score, and ROM of the hip joint at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P 0.05) except the Harris score (P fair in 6 hips

Effect of prosthesis endplate lordosis angles on L5-S1 kinematics after disc arthroplasty.

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Tsitsopoulos, Parmenion P; Wojewnik, Bartosz; Voronov, Leonard I; Havey, Robert M; Renner, Susan M; Zelenakova, Julia; McIntosh, Braden; Carandang, Gerard; Abjornson, Celeste; Patwardhan, Avinash G

2012-06-01

We hypothesized that L5-S1 kinematics will not be affected by the lordosis distribution between the prosthesis endplates. Twelve cadaveric lumbosacral spines (51.3 ± 9.8 years) were implanted with 6° or 11° prostheses (ProDisc-L) with four combinations of superior/inferior lordosis (6°/0°, 3°/3°, 11°/0°, 3°/8°). Specimens were tested intact and after prostheses implantation with different lordosis distributions. Center of rotation (COR) and range of motion (ROM) were quantified. Six-degree lordosis prostheses (n = 7) showed no difference in flexion-extension ROM, regardless of design (6°/0° or 3°/3°) (p > 0.05). In lateral bending (LB), both designs reduced ROM (p lordosis prostheses (n = 5) showed no difference in flexion-extension ROM for either design (p > 0.05). LB ROM decreased with distributed lordosis prostheses (3°/8°) (p lordosis distribution among the two prosthesis endplates. The ProDisc-L prosthesis design where all lordosis is concentrated in the superior endplate yielded COR locations that were anterior and caudal to intact controls. The prosthesis with lordosis distributed between the two endplates yielded a COR that tended to be closer to intact. Further clinical and biomechanical studies are needed to assess the long-term impact of lordosis angle distribution on the fate of the facet joints.

Semantic Feature Training in Combination with Transcranial Direct Current Stimulation (tDCS for Progressive Anomia

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Jinyi Hung

2017-05-01

Full Text Available We examined the effectiveness of a 2-week regimen of a semantic feature training in combination with transcranial direct current stimulation (tDCS for progressive naming impairment associated with primary progressive aphasia (N = 4 or early onset Alzheimer’s Disease (N = 1. Patients received a 2-week regimen (10 sessions of anodal tDCS delivered over the left temporoparietal cortex while completing a language therapy that consisted of repeated naming and semantic feature generation. Therapy targets consisted of familiar people, household items, clothes, foods, places, hygiene implements, and activities. Untrained items from each semantic category provided item level controls. We analyzed naming accuracies at multiple timepoints (i.e., pre-, post-, 6-month follow-up via a mixed effects logistic regression and individual differences in treatment responsiveness using a series of non-parametric McNemar tests. Patients showed advantages for naming trained over untrained items. These gains were evident immediately post tDCS. Trained items also showed a shallower rate of decline over 6-months relative to untrained items that showed continued progressive decline. Patients tolerated stimulation well, and sustained improvements in naming accuracy suggest that the current intervention approach is viable. Future implementation of a sham control condition will be crucial toward ascertaining whether neurostimulation and behavioral treatment act synergistically or alternatively whether treatment gains are exclusively attributable to either tDCS or the behavioral intervention.

[Study of satisfaction of testicular prosthesis implantation in children].

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Martínez, Y; Millán, A; Gilabert, R; Delgado, L; De Agustín, J C

2012-01-01

Testicular absence may cause psychological trauma in children. It can be avoided by placing testicular prosthesis (TP). However there is no consensus on the optimal age of implantation. We evaluate the results of TP implantation and their complications, as well as patient and family satisfaction. This is a retrospective study of TP implanted between 2004-2010 in our center. Variables analyzed are: age, size and side, indication, surgical technique, complications and comorbidity. Telephone survey was done by a single interviewer to 50 families. general family satisfaction, characteristics of the prosthesis (size, shape, location and consistency), body image and psychological situation of the child, duration of analgesia after surgery, reoperation rate, and family advice to other parents. Statistical analysis with SPSS-18.0. 107 prostheses were placed (4 bilateral, 64 left and 35 rights) at a mean age of 70,10 +/- 58,6 months. The most common indication was cryptorchidism (48.2%). Initial inguinal approach in 69%, and simultaneous contralateral orchidopexy in 29.9%. Only one patient refused the prostheses. In 71% the mother was interviewed. Parents consider size, shape and position appropriate in 55.6%, 66.7% and 82.22% respectively. Hard consistency of TP was considered in 82.3% of the patients. Psychological problems were absent in 86.7%. Nighty five percent would be willing to replace when it was necessary. Parents would recommend the intervention to parents in the same situation in 86.7%. Testicular prosthesis avoids psychological trauma. The lack of satisfaction regarding to the small size and hardness makes necessary to replace the TP in adulthood. An open question remains whether we should consider the placement of TP in early ages, or if we should establish some indications based on a more rational communication with the family.

Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis.

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Nakamura, Hiromasa; Yamaguchi, Hiroki; Takagaki, Masami; Kadowaki, Tasuku; Nakao, Tatsuya; Amano, Atsushi

2015-03-01

Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm(2) m(-2), has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus. Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m(2)) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery. Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm(2) m(-2). Moderate mismatch, defined as effective orifice area index ≤0.85 cm(2) m(-2), developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe. Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users

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Andrew Sawers; Brian J. Hafner

2018-01-01

Objective: Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Design: Cross-sectional. Participants: Unilateral lower-limb prosthesis users. Methods: Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalize...

The Development of Skull Prosthesis Through Active Contour Model.

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Chen, Yi-Wen; Shih, Cheng-Ting; Cheng, Chen-Yang; Lin, Yu-Cheng

2017-09-09

Skull defects result in brain infection and inadequate brain protection and pose a general danger to patient health. To avoid these situations and prevent re-injury, a prosthesis must be constructed and grafted onto the deficient region. With the development of rapid customization through additive manufacturing and 3D printing technology, skull prostheses can be fabricated accurately and efficiently prior to cranioplasty. However, an unfitted skull prosthesis made with a metal implant can cause repeated infection, potentially necessitating secondary surgery. This paper presents a method of creating suitably geometric graphics of skull defects to be applied in skull repair through active contour models. These models can be adjusted in each computed tomography slice according to the graphic features, and the curves representing the skull defect can be modeled. The generated graphics can adequately mimic the natural curvature of the complete skull. This method will enable clinical surgeons to rapidly implant customized prostheses, which is of particular importance in emergency surgery. The findings of this research can help surgeons provide patients with skull defects with treatment of the highest quality.

Bilateral electromyogram response latency following platform perturbation in unilateral transtibial prosthesis users: influence of weight distribution and limb position.

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Rusaw, David; Hagberg, Kerstin; Nolan, Lee; Ramstrand, Nerrolyn

2013-01-01

Appropriate muscular response following an external perturbation is essential in preventing falls. Transtibial prosthesis users lack a foot-ankle complex and associated sensorimotor structures on the side with the prosthesis. The effect of this lack on rapid responses of the lower limb to external surface perturbations is unknown. The aim of the present study was to compare electromyogram (EMG) response latencies of otherwise healthy, unilateral, transtibial prosthesis users (n = 23, mean +/- standard deviation [SD] age = 48 +/- 14 yr) and a matched control group (n = 23, mean +/- SD age = 48 +/- 13 yr) following sudden support-surface rotations in the pitch plane (toes-up and toes-down). Perturbations were elicited in various weight-bearing and limb-perturbed conditions. The results indicated that transtibial prosthesis users have delayed responses of multiple muscles of the lower limb following perturbation, both in the intact and residual limbs. Weight-bearing had no influence on the response latency in the residual limb, but did on the intact limb. Which limb received the perturbation was found to influence the muscular response, with the intact limb showing a significantly delayed response when the perturbation was received only on the side with a prosthesis. These delayed responses may represent an increased risk of falling for individuals who use transtibial prostheses.

[CLINICAL APPLICATION OF OXFORD MOBILE-BEARING BIPOLAR PROSTHESIS UNICOMPARTMENTAL KNEE ARTHROPLASTY FOR SINGLE COMPARTMENTAL KNEE OSTEOARTHRITIS].

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Wang, Shangzeng; Cheng, Shao; Wang, Yisheng

2016-01-01

To evaluate the effectiveness of Oxford mobile-bearing bipolar prosthesis unicompartmental knee arthroplasty (UKA) in the treatment of single compartmental knee osteoarthritis. Between June 2011 and July 2013, 22 cases of single compartmental knee osteoarthritis were treated by Oxford mobile-bearing bipolar prosthesis UKA. Of 22 cases, 8 were male and 14 were female with an average age of 65 years (range, 45-80 years); the left knee was involved in 12 cases, and the right knee in 10 cases, with a mean disease duration of 32.5 months (range, 8-90 months). The mean weight was 55.2 kg (range, 50-65 kg), and the mean body mass index was 20.8 kg/m2 (range, 17-25 kg/m2). Osteoarthritis involved in the single knee medial compartment in all patients. Knee society score (KSS) and range of motion (ROM) were measured to evaluate the knee joint function. Primary healing of incision was obtained in all patients, and there was no complication of infection, bedsore, or deep venous thrombosis. Postoperative follow-up was 2-4 years (mean, 3.2 years). The X-ray films showed good position of prosthesis, no prosthesis dislocation, or periprosthetic infection during follow-up. Knee ROM, KSS function score, and KSS clinical score were significantly improved at 1 week after operation and at last follow-up when compared with preoperative ones (P 0.05). Oxford mobile-bearing bipolar prosthesis UKA is an effective method to treat single compartmental knee osteoarthritis, with the advantages of less trauma, earlier rehabilitation exercise, near physiological state in joint function, and less risk of complications.

Patient-prosthesis mismatch and left ventricular remodelling after implantation of Shelhigh SuperStentless aortic valve prostheses.

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Germing, A; Lindstaedt, M; Holt, S; Reber, D; Mügge, A; Laczkovics, A; Fritz, M

2008-08-01

Aortic valve replacement is a standard procedure for the treatment of severe aortic valve stenosis. Due to lower flow velocities stentless valves are associated with a more effective regression of left ventricular hypertrophy in comparison to stented valves. However, mismatch between body surface area and valve size supports unfavourable hemodynamic results. The aim of the study was to analyze hemodynamic parameters by echocardiography after implantation of the Shelhigh SuperStentless bioprosthesis and to analyze the occurrence of patient-prosthesis mismatch and left ventricular remodelling in this specific valve type. A total of 20 patients with severe aortic stenosis underwent implantation of a Shelhigh Super Stentless prosthesis. Clinical and echocardiographic assessment was done prior to, immediate after and six months after surgery. All surgical procedures were successful, no surgery-related complication was documented perioperatively. One patient died after development of multiorgan failure. Echocardiography during the first eight days after surgery showed mean gradients of 16 mmHg, mean valve orifice areas of 1.8 cm(2) and indexed effective orifice areas at 0.95 cm(2)/m(2). Six-months follow-up data were obtained in 19/20 patients. There were no relevant changes in echocardiographic hemodynamic findings at the time of follow-up measurements. Significant regression of left ventricular hypertrophy was shown (P=0.0088). A patient-prosthesis mismatch occurred in one patient (0.54 cm(2)/m(2)). No recurrent symptoms were documented. Patient-prosthesis mismatch after implantation of SuperStentless Shelhigh prosthesis is rare. A significant regression of left ventricular hypertrophy could be shown after six months. Hemodynamic valve function assessed by echocardiography may be predicted early after surgery.

Wear-testing of a temporomandibular joint prosthesis : UHMWPE and PTFE against a metal ball, in water and in serum

NARCIS (Netherlands)

Van Loon, JP; Verkerke, GJ; de Bont, LGM; Liem, RSB

For a temporomandibular joint prosthesis, an estimation of the wear rate was needed, prior to patient application. Therefore, we determined the in vitro wear rate of the ball-socket articulation of this prosthesis, consisting of a metal head and an ultra-high molecular weight polyethylene (UHMWPE)

Strain-stress analysis of surface prosthesis of hip joint

Czech Academy of Sciences Publication Activity Database

Návrat, Tomáš; Fuis, Vladimír; Florian, Z.; Hlavoň, Pavel

2007-01-01

Roč. 40, č. 2 (2007), S559-S559 ISSN 0021-9290. [ISB 2007. Taipei, 01.07.2007-05.07.2007] R&D Projects: GA ČR GA101/05/0136 Institutional research plan: CEZ:AV0Z20760514 Keywords : surface prosthesis * hip joint * FEM Subject RIV: BO - Biophysics Impact factor: 2.897, year: 2007

Penile prosthesis implant with bi-triangular excision and graft for surgical therapy of Peyronie’s disease: A case report

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Alexandre de Freitas Miranda

2016-01-01

Full Text Available We present a case of a 65-year-old man, who presented with moderate erectile dysfunction and a dorsal penile deviation of 60° caused by Peyronie’s disease. The patient underwent bi-triangularshaped plaque excision, followed by grafting and implantation of inflatable penile prosthesis. Complete penile straightening, without mechanical or geometric abnormalities, was achieved using bi-triangular excision and grafting. Postoperatively, the patient reported high satisfaction with the results and could perform sexual intercourse naturally. This novel technique corrects any degree of penile curvature, permits malleable and semi-rigid penile prosthesis implantation, avoids penile length loss, and eliminates additional incisions. To our knowledge, this case is the first in the literature in which the bi-triangular technique was successfully used for penile prosthesis implantation secondary to Peyronie’s disease. This new technique appears to be a good solution to correct penile curvature during penile prosthesis implantation for the treatment of Peyronie’s disease associated with erectile dysfunction.

Three-Dimensional Printed Prosthesis for Repair of Superior Canal Dehiscence.

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Kozin, Elliott D; Remenschneider, Aaron K; Cheng, Song; Nakajima, Hideko Heidi; Lee, Daniel J

2015-10-01

Outcomes following repair of superior canal dehiscence (SCD) are variable, and surgery carries a risk of persistent or recurrent SCD symptoms, as well as a risk of hearing loss and vestibulopathy. Poor outcomes may occur from inadequate repair of the SCD or mechanical insult to the membranous labyrinth. Repair of SCD using a customized, fixed-length prosthesis may address current operative limitations and improve surgical outcomes. We aim to 3-dimensionally print customized prostheses to resurface or occlude bony SCD defects. Dehiscences were created along the arcuate eminence of superior semicircular canals in cadaveric temporal bones. Prostheses were designed and created using computed tomography and a 3-dimensional printer. The prostheses occupied the superior semicircular canal defect, reflected in postrepair computed tomography scans. This novel approach to SCD repair could have advantages over current techniques. Refinement of prosthesis design and materials will be important if this approach is translated into clinical use. © American Academy of Otolaryngology-Head and Neck Surgery Foundation 2015.

Predictors of retention and attrition in a study of an advanced upper limb prosthesis: implications for adoption of the DEKA Arm.

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Resnik, Linda; Cancio, Jill; Klinger, Shana; Latlief, Gail; Sasson, Nicole; Smurr-Walters, Lisa

2018-02-01

The purpose was to identify factors associated with completion of the VA home study of the DEKA Arm. Design and methodological procedures used: Differences between groups were examined using chi-square and t-tests. A multivariable logistic regression model predicting completion was generated and odds ratios (OR) for significant variables calculated. Post-hoc analysis was performed to plot the receiver operating characteristics (ROC) curve. Participants who completed were more likely to be prosthesis users at study onset (p = .03), and less likely to have a history of musculoskeletal problems (p = .047). There were no statistically significant differences between groups who completed and those who did not in gender, race, veteran status, age, body mass index (BMI), weight, height, musculoskeletal pain at baseline, satisfaction with current prosthesis, type of prosthesis, or months of prosthesis use. Two variables, prosthesis use and history of musculoskeletal problems were significant at p study a reasonable proxy for participant willingness to adopt the device; and believe that findings can be extrapolated to guide DEKA Arm prescription recommendations. Participants most likely to complete the study were already using a personal prosthesis, and without pre-existing musculoskeletal problems. Implications for rehabilitation Data from the VA Study of the DEKA Arm were analysed to determine which factors were associated with likely successful adoption of the DEKA Arm. Participants most likely to complete the study were those who already using a personal prosthesis, and those without pre-existing chronic or re-occurring musculoskeletal problems. This information may be useful when attempting to identify and target the most appropriate candidates for DEKA Arm prescription.

Silver-coated dacron prosthesis in the treatment of infection in arterial surgery: Case reports

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Nenezić Dragoslav

2008-01-01

Full Text Available INTRODUCTION Although the incidence is low, infection of prosthetic vascular graft bears a high incidence of serious complications including 25-75% mortality rate and 40-75% limb loss. The standard treatment of vascular graft infection consists of excision of the prosthesis, wound debridement and extraanatomic revascularization. Conservative treatment might be an option in a limited number of patients. We present three cases of surgical and conservative treatment of vascular graft infection. CASE OUTLINE Case 1: A patient developed silver-coated graft infection after femorodistal arterial reconstruction performed because of critical limb ischemia. In the early postoperative period, massive skin and subcutaneous tissue necrosis developed, with the graft being exposed. After two months of persistent debridement and wound toilette, the defect was covered with a Thiersch skin graft. Case 2: PTFE graft infection in the right groin followed reconstruction of the isolated common femoral artery aneurysm. This graft was replaced with a silver-coated graft in situ. Reinfection of the proximal end of the implanted silver-coated graft occurred and the graft was exposed. After repeated debridement and wound toilette, the exposed prosthesis was covered with granulomatous tissue, and the wound healed. Case 3: A year after anastomotic pseudoaneurysm resection in the left groin, prosthesis was exposed following wound infection. This graft was substituted with a silver-coated graft in situ. The wound healed primarily. CONCLUSION These three cases demonstrate that under some circumstances vascular prosthesis infection can be successfully treated conservatively without graft removal, and also by in situ replacement using silver-coated graft.

Fabrication of a hollow bulb prosthesis for the rehabilitation of an acquired total maxillectomy defect

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Vamsi Krishna, C H; Babu, Jaya Krishna; Fathima, Tanveer; Reddy, G V K

2014-01-01

The prosthodontic rehabilitation of maxillary defects is a challenging and demanding task which requires careful pre-surgical and post-surgical planning. Maxillary defects can be congenital or acquired. Acquired defects include those following trauma or surgical treatment of benign or malignant neoplasms. A prosthodontist encounters problems such as absence of support, poor retention, and lack of prosthesis stability in treating these patients. The present case report describes a procedure to fabricate a definitive hollow bulb obturator prosthesis for the rehabilitation of a total maxillectomy defect. PMID:24671313

EVALUATION AND RANKING OF ARTIFICIAL HIP PROSTHESIS SUPPLIERS BY USING A FUZZY TOPSIS METHODOLOGY

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Marija Zahar Djordjevic

2014-06-01

Full Text Available The aim of this study is to propose a fuzzy multi-criteria decision-making approach (MCDM to evaluate the artificial hip prosthesis suppliers with respect to numerous criteria, simultaneously, taking into account the type of each criteria and its relative importance. The fuzzy of the Technique for Order Preference by Similarity to Ideal Solution (FTOSISis applied in order to rank the artificial hip prosthesis suppliers. The rank is obtained using the process of fuzzy number comparison. Software solution based on suggested method is also presented. A real-life example with real data is presented to clarify the proposed method.

Tactile feedback is an effective instrument for the training of grasping with a prosthesis at low- and medium-force levels.

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De Nunzio, Alessandro Marco; Dosen, Strahinja; Lemling, Sabrina; Markovic, Marko; Schweisfurth, Meike Annika; Ge, Nan; Graimann, Bernhard; Falla, Deborah; Farina, Dario

2017-08-01

Grasping is a complex task routinely performed in an anticipatory (feedforward) manner, where sensory feedback is responsible for learning and updating the internal model of grasp dynamics. This study aims at evaluating whether providing a proportional tactile force feedback during the myoelectric control of a prosthesis facilitates learning a stable internal model of the prosthesis force control. Ten able-bodied subjects controlled a sensorized myoelectric prosthesis performing four blocks of consecutive grasps at three levels of target force (30, 50, and 70%), repeatedly closing the fully opened hand. In the first and third block, the subjects received tactile and visual feedback, respectively, while during the second and fourth block, the feedback was removed. The subjects also performed an additional block with no feedback 1 day after the training (Retest). The median and interquartile range of the generated forces was computed to assess the accuracy and precision of force control. The results demonstrated that the feedback was indeed an effective instrument for the training of prosthesis control. After the training, the subjects were still able to accurately generate the desired force for the low and medium target (30 and 50% of maximum force available in a prosthesis), despite the feedback being removed within the session and during the retest (low target force). However, the training was substantially less successful for high forces (70% of prosthesis maximum force), where subjects exhibited a substantial loss of accuracy as soon as the feedback was removed. The precision of control decreased with higher forces and it was consistent across conditions, determined by an intrinsic variability of repeated myoelectric grasping. This study demonstrated that the subject could rely on the tactile feedback to adjust the motor command to the prosthesis across trials. The subjects adjusted the mean level of muscle activation (accuracy), whereas the precision could not

Designing and manufacturing an auricular prosthesis using computed tomography, 3-dimensional photographic imaging, and additive manufacturing: a clinical report.

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Liacouras, Peter; Garnes, Jonathan; Roman, Norberto; Petrich, Anton; Grant, Gerald T

2011-02-01

The method of fabricating an auricular prosthesis by digitally positioning a mirror image of the soft tissue, then designing and using rapid prototyping to produce the mold, can reduce the steps and time needed to create a prosthesis by the traditional approach of sculpting either wax or clay. The purpose of this clinical report is to illustrate how the use of 3-dimensional (3-D) photography, computer technology, and additive manufacturing can extensively reduce many of the preliminary procedures currently used to create an auricular prosthesis. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

The influence of push-off timing in a robotic ankle-foot prosthesis on the energetics and mechanics of walking.

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Malcolm, Philippe; Quesada, Roberto E; Caputo, Joshua M; Collins, Steven H

2015-02-22

Robotic ankle-foot prostheses that provide net positive push-off work can reduce the metabolic rate of walking for individuals with amputation, but benefits might be sensitive to push-off timing. Simple walking models suggest that preemptive push-off reduces center-of-mass work, possibly reducing metabolic rate. Studies with bilateral exoskeletons have found that push-off beginning before leading leg contact minimizes metabolic rate, but timing was not varied independently from push-off work, and the effects of push-off timing on biomechanics were not measured. Most lower-limb amputations are unilateral, which could also affect optimal timing. The goal of this study was to vary the timing of positive prosthesis push-off work in isolation and measure the effects on energetics, mechanics and muscle activity. We tested 10 able-bodied participants walking on a treadmill at 1.25 m · s(-1). Participants wore a tethered ankle-foot prosthesis emulator on one leg using a rigid boot adapter. We programmed the prosthesis to apply torque bursts that began between 46% and 56% of stride in different conditions. We iteratively adjusted torque magnitude to maintain constant net positive push-off work. When push-off began at or after leading leg contact, metabolic rate was about 10% lower than in a condition with Spring-like prosthesis behavior. When push-off began before leading leg contact, metabolic rate was not different from the Spring-like condition. Early push-off led to increased prosthesis-side vastus medialis and biceps femoris activity during push-off and increased variability in step length and prosthesis loading during push-off. Prosthesis push-off timing had no influence on intact-side leg center-of-mass collision work. Prosthesis push-off timing, isolated from push-off work, strongly affected metabolic rate, with optimal timing at or after intact-side heel contact. Increased thigh muscle activation and increased human variability appear to have caused the lack

A proposed intracortical visual prosthesis image processing system.

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Srivastava, N R; Troyk, P

2005-01-01

It has been a goal of neuroprosthesis researchers to develop a system, which could provide artifical vision to a large population of individuals with blindness. It has been demonstrated by earlier researches that stimulating the visual cortex area electrically can evoke spatial visual percepts, i.e. phosphenes. The goal of visual cortex prosthesis is to stimulate the visual cortex area and generate a visual perception in real time to restore vision. Even though the normal working of the visual system is not been completely understood, the existing knowledge has inspired research groups to develop strategies to develop visual cortex prosthesis which can help blind patients in their daily activities. A major limitation in this work is the development of an image proceessing system for converting an electronic image, as captured by a camera, into a real-time data stream for stimulation of the implanted electrodes. This paper proposes a system, which will capture the image using a camera and use a dedicated hardware real time image processor to deliver electrical pulses to intracortical electrodes. This system has to be flexible enough to adapt to individual patients and to various strategies of image reconstruction. Here we consider a preliminary architecture for this system.

Psychosocial impact on anophthalmic patients wearing ocular prosthesis.

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Goiato, M C; dos Santos, D M; Bannwart, L C; Moreno, A; Pesqueira, A A; Haddad, M F; dos Santos, E G

2013-01-01

The aim of this study was to assess the improvement in psychosocial awareness of anophthalmic patients wearing ocular prostheses and its relationship with demographic characteristics, factors of loss/treatment, social activity, and relationship between professional and patient. Surveys including a form for evaluation of psychosocial pattern were conducted with 40 anophthalmic patients rehabilitated with ocular prosthesis at the Center of Oral Oncology in the authors' dental school from January 1998 to November 2010. The improvement in psychosocial awareness was assessed by comparing the perception of some feelings reported in the period of eye loss and currently. Wilcoxon tests were applied for comparison of patients' perception between the periods. χ(2) tests were used to assess the relationship between the improvement in psychosocial awareness and the variables of the study. In addition, the logistic regression model measured this relationship with the measure of odds ratio. The feelings of shame, shyness, preoccupation with hiding it, sadness, insecurity and fear were significant for improvement in psychosocial awareness. It was concluded that the anophthalmic patients wearing an ocular prosthesis has significant improvement in psychosocial awareness after rehabilitation. Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Reconstruction of a midfacial defect using an intraoral-extraoral combination prosthesis employing magnets: a clinical report

OpenAIRE

Nair, Anoop; Regish, K M.; Shah, Farhan K.; Prithviraj, D R.

2012-01-01

Radical maxillectomy frequently leads to extended defects in hard and soft tissues that result in a connection between the oral cavities and orbit. If the defect cannot be surgically reconstructed, a combination prosthesis may be necessary to remedy dysfunction in patient function, comfort, esthetics. For minor defects, enlargement of the base of the intra oral prosthesis is generally sufficient. Resections that affect more than one third of the maxilla usually require an intra oral and an ex...

Mechanical properties of ramie fiber reinforced epoxy lamina composite for socket prosthesis

Directory of Open Access Journals (Sweden)

Tresna Soemardi

2010-10-01

Full Text Available This paper presents an investigation into the application of natural fiber composite especially ramie fiber reinforced epoxy lamina composite for socket prosthesis. The research focuses on the tensile and shear strength from ramie fiber reinforced epoxy lamina composite which will be applied as alternative material for socket prosthesis. The research based on American Society for Testing Material (ASTM standard D 3039/D 3039M for tensile strength and ASTM D 4255/D 4255M-83 for shear strength. The ramie fiber applied is a fiber continue 100 % Ne14'S with Epoxy Resin Bakelite EPR 174 as matrix and Epoxy Hardener V-140 as hardener. The sample composite test made by hand lay up method. Multiaxial characteristic from ramie fiber reinforced epoxy composite will be compared with ISO standard for plastic/polymer for health application and refers strength of material application at Prosthetics and Orthotics. The analysis was completed with the mode of the failure and the failure criterion observation by using Scanning Electron Microscope (SEM. Based on results of the research could be concluded that ramie fiber reinforced epoxy composite could be developed further as the alternative material for socket prosthesis on Vf 40-50%. Results of the research will be discussed in more detail in this paper.

Atraumatic patellar prosthesis dislocation with patellar tendon injury following a total knee arthroplasty: a case report

Directory of Open Access Journals (Sweden)

Singh Alka

2010-01-01

Full Text Available Abstract Introduction Total knee arthroplasty is a well-established procedure with gratifying results. There is no consensus in the literature whether to routinely resurface the patella while performing total knee arthroplasty or not. Although an extremely rare occurrence in clinical practice, patellar prosthesis dislocation is a possible complication resulting from total knee arthroplasty. Case presentation We report a rare case of atraumatic spontaneous dislocation of patellar prosthesis in a 63-year-old Caucasian man of British origin with patellar tendon injury. The patient was treated successfully through a revision of the patellar component and tendon repair. In two years follow-up the patient is asymptomatic with no sign of loosening of his patellar prosthesis. Conclusions A thorough understanding of knee biomechanics is imperative in performing total knee arthroplasty in order to achieve a better functional outcome and to prevent early prosthetic failure.

[Dislocated fracture of the lesser trochanter with malrotation of the stem after robot assisted implantation of a cementless hip prosthesis: a casuistic report].

Science.gov (United States)

Prymka, M; Hassenpflug, J

2003-08-01

This paper presents the case of a 63 year old female with a severe coxarthrosis. She got a robot assited implantation of a cementless hip prosthesis (Osteolock, Stryker-Howmedica, Mühlheim). As operation robot the CASPAR-System (Orto-Maquet, Rastatt) was used. Initially, the clinical progress of the patient was fine. She was nearly painfree within 14 days and showed an acceptable range of motion in the operated joint (flexion/ extension 90 degrees /05 degrees /00 degrees ). She was mobilized with crutches and 15 kg weight bearing at the operated leg. 3 weeks postoperative the patient complaint about increasing pain without trauma or intensification of the weight bearing. X-rays showed not only a dislocated fracture of the lesser trochanter, but also a sinking combined with a malrotation of the stem. A revision operation was necessary,where we implanted a cemented stem. Now clinical progress was completely satisfying.

Prosthetic Rehabilitation of a Patient with Mandibular Resection Prosthesis Using Mini Dental Implants (MDIs) – Case Report

OpenAIRE

Vojvodić, Denis; Čelebić, Asja; Mehulić, Ketij; Žabarović, Domagoj

2012-01-01

Physical disfigurement and functional impairments associated with facial trauma are a challenge to a prosthodontist, because even novel sophisticated surgical reconstructive techniques fail to provide adequate support for dental resection prosthesis. Therefore, different endosseous implants are often used as prosthesis-supporting elements. Manufacturers of dental implants have recently presented mini dental implants (MDIs) with diameter of only 1.8–2.4 mm. These implants allow very suitable p...

Classification of EMG signals using artificial neural networks for virtual hand prosthesis control.

Science.gov (United States)

Mattioli, Fernando E R; Lamounier, Edgard A; Cardoso, Alexandre; Soares, Alcimar B; Andrade, Adriano O

2011-01-01

Computer-based training systems have been widely studied in the field of human rehabilitation. In health applications, Virtual Reality presents itself as an appropriate tool to simulate training environments without exposing the patients to risks. In particular, virtual prosthetic devices have been used to reduce the great mental effort needed by patients fitted with myoelectric prosthesis, during the training stage. In this paper, the application of Virtual Reality in a hand prosthesis training system is presented. To achieve this, the possibility of exploring Neural Networks in a real-time classification system is discussed. The classification technique used in this work resulted in a 95% success rate when discriminating 4 different hand movements.

78 FR 9010 - Dental Devices; Reclassification of Temporary Mandibular Condyle Prosthesis

Science.gov (United States)

2013-02-07

.... FDA-2012-N-1239] Dental Devices; Reclassification of Temporary Mandibular Condyle Prosthesis AGENCY... condyle prostheses into class III, based on the recommendation of a Dental Products Panel (the Panel... Administration, Dental Products Advisory Panel Meeting Transcript, February 12, 1997; http://www.accessdata.fda...

VARIABLE STIFFNESS HAND PROSTHESIS: A SYSTEMATIC REVIEW

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S. Cecilia Tapia-Siles

2017-06-01

Full Text Available Prosthetics is an important field in engineering due to the large number of amputees worldwide and the associated problems such as limited functionality of the state of the art. An important functionality of the human hand is its capability of adjusting the stiffness of the joints depending on the currently performed task. For the development of new technology it is important to understand the limitations of existing resources. As part of our efforts to develop a variable stiffness grasper for developing countries a systematic review was performed covering technology of body powered and myoelectric hand prosthesis. Focus of the review is readiness of prosthetic hands regarding their capability of controlling the stiffness of the end effector. Publications sourced through three different digital libraries were systematically reviewed on the basis of the PRISMA standard. We present a search strategy as well as the PRISMA assessment of the resulting records which covered 321 publications. The records were assessed and the results are presented for the ability of devices to control their joint stiffness. The review indicates that body powered prosthesis are preferred to myoelectric hands due to the reduced cost, the simplicity of use and because of their inherent ability to provide feedback to the user. Stiffness control was identified but has not been fully covered in the current state of the art. In addition we summarise the identified requirements on prosthetic hands as well as related information which can support the development of new prosthetics.

Stent valve implantation in conventional redo aortic valve surgery to prevent patient-prosthesis mismatch.

Science.gov (United States)

Ferrari, Enrico; Franciosi, Giorgio; Clivio, Sara; Faletra, Francesco; Moccetti, Marco; Moccetti, Tiziano; Pedrazzini, Giovanni; Demertzis, Stefanos

2017-03-01

The goal was to show the technical details, feasibility and clinical results of balloon-expandable stent valve implantation in the aortic position during conventional redo open-heart surgery in selected obese patients with a small aortic prosthesis and severe patient-prosthesis mismatch. Two symptomatic overweight patients (body mass index of 31 and 38), each with a small aortic prosthesis (a 4-year-old, 21-mm Hancock II biological valve and a 29-year-old, 23-mm Duromedic mechanical valve), increased transvalvular gradients (59/31 and 74/44 mmHg) and a reduced indexed effective orifice area (0.50 and 0.43 cm 2 /m 2 ) underwent implantation of two 26-mm balloon-expandable Sapien 3 valves during standard on-pump redo valve surgery. Using full re-sternotomy, cardiopulmonary bypass and cardioplegic arrest, the two balloon-expandable stent valves were implanted under direct view using a standard aortotomy, after prosthesis removal and without annulus enlargement. Aortic cross-clamp times were 162 and 126 min; cardiopulmonary bypass times were 178 and 180 min; total surgical times were 360 and 318 min. At discharge, echocardiograms showed transvalvular peak and mean gradients of 13/9 and 23/13 mmHg and indexed effective orifice areas of 0.64 and 1.08 cm 2 /m 2 . The 3-month echocardiographic follow-up showed transvalvular peak and mean gradients of 18/9 and 19/11 mmHg and indexed effective orifice areas of 0.78 cm 2 /m 2 and 0.84 cm 2 /m 2 , with improved symptoms (New York Heart Association class 1). Implantation of a balloon-expandable stent valve during redo aortic valve surgery is feasible in selected cases and prevents patient-prosthesis mismatch in obese patients without need for aortic annulus enlargement. Moreover, in the case of stent valve degeneration, this approach permits additional valve-in-valve procedures with large stent valves and prevents re-redo surgery. © The Author 2016. Published by Oxford University Press on behalf of the

Indeks Massa Tubuh dengan Keseimbangan Statis Pengguna Transtibial Prosthesis

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Nur Rachmat

2017-11-01

Full Text Available The balance of a person's body is affected by the Body Mass Index. Body Mass Index is the easiest way to estimate obesity as well as to be highly correlated with body fat mass, but it is also important to identify obese patients who have a risk of medical complications. Purpose of this study was to know correlation body mass index with the static balance of transtibial prosthesis user. The study was a quantitative research with a cross-sectional design. Location research in BBRSBD Prof. Dr. Soeharso Surakarta with sample were patients with post-amputation of transtibial as many as 15 people. Analysis of data was used correlation Pearson test. There was a correlation between body mass index with the static balance of transtibial prosthesis user, the coefficient correlation of -0.646 with significant and levels of correlation moderate. The value of normal body mass index has the highest static balance than lean body mass index and fat. Mass Index of the skinny body has a moderate static balance. Obese body mass index has the lowest static balance of body mass index thin and normal.

Adhesive strength of hydroxyl apatite(HA) coating and biomechanics behavior of HA-coated prosthesis:an experimental study

OpenAIRE

Tian-yang ZHANG; Yong-hong DUAN; Shu ZHU; Jin-yu ZHU; Qing-sheng ZHU

2011-01-01

Objective To explore the influence of adhesive strength of hydroxyapatite(HA) coating on the post-implantation stability of HA-coated prosthesis.Methods The adhesive strength and biomechanics behavior of HA coating were studied by histopathological observation,material parameters and biomechanical testing,the titanium(Ti)-coated prosthesis was employed as control.Results Scratch test showed that the adhesive strength of HA coating was significantly lower than that of Ti coating(P < 0.01).Hist...

The effects of static friction and backlash on extended physiological proprioception control of a powered prosthesis.

Science.gov (United States)

Farrell, Todd R; Weir, Richard F; Heckathorne, Craig W; Childress, Dudley S

2005-01-01

In general, externally powered prostheses do not provide proprioceptive feedback and thus require the user to rely on cognitively expensive visual feedback to effectively control the prosthesis. Applying the concept of extended physiological proprioception (EPP) to externally powered prostheses provides direct feedback to the user's proprioceptive system regarding the position, velocity, and forces applied to the prosthesis. However, electric elbows with EPP controllers developed at the Northwestern University Prosthetics Research Laboratory have exhibited unexplained "jerky" behavior in both clinical fittings and bench-top operation. In addition, the development of limit cycles, a specific type of constant-amplitude oscillation, had been observed in bench-top use of these elbows. Backlash and static friction within the EPP system were found to be primarily responsible for the development of limit cycles. Reducing static friction and backlash improved the system's performance. These results suggest that to most effectively implement EPP, prosthesis manufacturers should design prosthetic components that minimize static friction and backlash.

The Metal-Zirconia Implant Fixed Hybrid Full-Arch Prosthesis: An Alternative Technique for Fabrication.

Science.gov (United States)

Stumpel, Lambert J; Haechler, Walter

2018-03-01

The metal-resin hybrid full-arch prosthesis has been a traditionally used type of restoration for full-arch implant fixed dentures. A newer development has centered around the use of monolithic zirconia or zirconia veneered with porcelain. Being a ceramic, zirconia has the potential for fracture. This article describes a technique that utilizes a metal substructure to support a chemically and mechanically resinbonded shell of zirconia. The workflow is discussed, ranging from in-office master cast fabrication to the CAD/ CAM production of the provisional and the definitive metal-zirconia prosthesis. The article also highlights the advantages and disadvantages of various materials used for hybrid prostheses.

WalkMECH: design and control of an energy recycling transfemoral prosthesis

NARCIS (Netherlands)

Ünal, Ramazan

2014-01-01

This study presents the design and realization of an energy-efficient trans-femoral prosthesis called WalkMECH. Trans-femoral amputees consume significant amount of extra metabolic energy (more than 65% extra) during walking compared to the able- bodied person. Therefore, we mainly focused on the

Transapical JenaValve in a patient with mechanical mitral valve prosthesis.

LENUS (Irish Health Repository)

O' Sullivan, Katie E

2014-01-29

We report the first case of transcatheter aortic valve replacement implantation using JenaValve™ in a patient with mechanical mitral valve prosthesis. We believe that the design features of this valve may be particularly suited for use in this setting. © 2014 Wiley Periodicals, Inc.

Tubing erosion of an inflatable penile prosthesis long after implantation.

Science.gov (United States)

Morales, Alvaro

2014-06-01

Erosion through skin of connecting tubing of an inflatable penile prosthesis (IPP) has not been previously reported. The aim of this study was to present a case of tubing erosion, review the pertinent literature, and discuss the possible causes and management options, including preservation of the device and its components. A 42-year-old male failing to respond to medical treatment for erectile dysfunction underwent insertion of an AMS 700 IPP in 1986. Six years later, a revision was necessary because of a leak in the right cylinder and 4 years after, the pump was replaced. Fourteen years after the original implant, he presented with a portion of the tube connecting the pump to the right cylinder eroding through the skin. There was no infection. The skin area involved was resected and the original pump and tubing were buried in a new scrotal pocket after thorough irrigation. The IPP remained in place, allowing vaginal penetration and without infection for another 11 years. Three years later, it was de-functionalized, converted into a fixed volume device. It eventually was replaced 25 years after originally implanted with a semirigid prosthesis because it did not provide sufficient rigidity and because of concerns about the presence of "screws" detected during pelvic imaging. Mechanical failures in the early IPP models, as illustrated in this case, were expected. However, the long survival of the device is remarkable. Erosion of the connecting tubing through the skin is unique and, under exceptional circumstances, may be managed conservatively without replacing components of the IPP. Clinicians unfamiliar with procedures involving inflatable devices need to be aware of "foreign bodies" visible in radiological examinations in men who have had revisions of an IPP. Morales A. Tubing erosion of an inflatable penile prosthesis long after implantation. Sex Med 2014;2:103-106.

Distal corporoplasty for distal cylinders extrusion after penile prosthesis implantation.

Science.gov (United States)

Carrino, Maurizio; Chiancone, Francesco; Battaglia, Gaetano; Pucci, Luigi; Fedelini, Paolo

2017-02-03

Distal extrusion of cylinders is a potential complication of the penile prosthesis implantation. Several methods have been proposed for repairing a distal penile erosion. We present our preliminary experience in "Distal corporoplasty" technique. We enrolled 18 consecutive patients whose underwent a distal corporoplasty with simultaneous reimplantation of an "AMS 700 inflatable penile prosthesis (LGX)" from January 2013 to November 2015 at our hospital. All procedures were performed by a single surgical team. Intraoperative and postoperative complications have been classified and reported according to Satava6 and Clavien-Dindo (CD) system.7 Mean values with standard deviations (±SD) were computed and reported for all items. Mean age of the patients was 53.61 (±11.90) years. Mean body max index (BMI) was 24.22 (±2.51). Mean operative time was 85.2 (±13.1) minutes. Blood losses were minimal. No intraoperative complications are reported according to Satava classification. Four out of 18 patients (22.22%) experienced postoperative complications according to CD system. All patients had sexual intercourse for the first time postsurgery after a mean of 59.11 ± 2.08 days. Mean follow-up was 22.11 (±9.95). Distal extrusion of cylinders is a potential complication of the penile prosthesis implantation. Distal corporoplasty was first described by Mulcahy. He reported a series of 14 patients with a follow-up of about 2 years with optimal functional outcomes. Moreover, distal corporoplasty resulted in shorter operative time, better function, less pain, and fewer recurrences than Gortex windsock repair.10 In our experience, distal corporoplasty is a simple and safe procedure in the treatment of distal cylinders extrusion when the prosthetic material is not exposed to the exterior.

Prosthesis-guided implant restoration of an auricular defect using computed tomography and 3-dimensional photographic imaging technologies: a clinical report.

Science.gov (United States)

Wang, Shuming; Leng, Xu; Zheng, Yaqi; Zhang, Dapeng; Wu, Guofeng

2015-02-01

The concept of prosthesis-guided implantation has been widely accepted for intraoral implant placement, although clinicians do not fully appreciate its use for facial defect restoration. In this clinical report, multiple digital technologies were used to restore a facial defect with prosthesis-guided implantation. A simulation surgery was performed to remove the residual auricular tissue and to ensure the correct position of the mirrored contralateral ear model. The combined application of computed tomography and 3-dimensional photography preserved the position of the mirrored model and facilitated the definitive implant-retained auricular prosthesis. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

A phantom study of dose compensation behind hip prosthesis using portal dosimetry and dynamic MLC

International Nuclear Information System (INIS)

Nielsen, Martin Skovmos; Carl, Jesper; Nielsen, Jane

2008-01-01

Background and purpose: A dose compensation method is presented for patients with hip prosthesis based on Dynamic Multi Leaves Collimator (DMLC) planning. Calculations are done from an exit Portal Dose Image (PDI) from 6 MV Photon beam using an Electronic Portal Imaging Device (EPID) from Varian. Four different hip prostheses are used for this work. Methods: From an exit PDI the fluence needed to yield a uniform dose distribution behind the prosthesis is calculated. To back-project the dose distribution through the phantom, the lateral scatter is removed by deconvolution with a point spread function (PSF) determined for depths from 10 to 40 cm. The dose maximum, D max , is determined from the primary plan which delivers the PDI. A further deconvolution to remove the dose glare effect in the EPID is performed as well. Additionally, this calculated fluence distribution is imported into the Treatment Planning System (TPS) for the final calculation of a DMLC plan. The fluence file contains information such as the relative central axis (CAX) position, grid size and fluence size needed for correct delivery of the DMLC plan. GafChromic EBT films positioned at 10 cm depth are used as verification of uniform dose distributions behind the prostheses. As the prosthesis is positioned at the phantom surface the dose verifications are done 10 cm from the prosthesis. Conclusion: The film measurement with 6 MV photon beam shows uniform doses within 5% for most points, but with hot/cold spots of 10% near the femoral head prostheses

Partial-limb salvage after persistent infection in the distal femoral prosthesis: straight-plasty - a novel technique

International Nuclear Information System (INIS)

Kundu, Z. S.; Gupta, V.; Gogna, P.

2014-01-01

A 35 years old female had giant cell tumour (GCT) of the distal femur for which wide resection and distal femoral endoprosthetic replacement was performed. Massive infection of prosthesis required removal and replacement of the prosthesis with nail antibiotic cement spacer, which also proved to be futile. Ultimately the whole of the infected thigh had to be excised. The limb could be preserved partially using straight-plasty instead of amputation. Patient is well rehabilitated and doing well at a follow-up of 3 years. (author)

Kinematic Measurement of Knee Prosthesis from Single-Plane Projection Images

Science.gov (United States)

Hirokawa, Shunji; Ariyoshi, Shogo; Takahashi, Kenji; Maruyama, Koichi

In this paper, the measurement of 3D motion from 2D perspective projections of knee prosthesis is described. The technique reported by Banks and Hodge was further developed in this study. The estimation was performed in two steps. The first-step estimation was performed on the assumption of orthogonal projection. Then, the second-step estimation was subsequently carried out based upon the perspective projection to accomplish more accurate estimation. The simulation results have demonstrated that the technique archived sufficient accuracies of position/orientation estimation for prosthetic kinematics. Then we applied our algorithm to the CCD images, thereby examining the influences of various artifacts, possibly incorporated through an imaging process, on the estimation accuracies. We found that accuracies in the experiment were influenced mainly by the geometric discrepancies between the prosthesis component and computer generated model and by the spacial inconsistencies between the coordinate axes of the positioner and that of the computer model. However, we verified that our algorithm could achieve proper and consistent estimation even for the CCD images.

[The endo-exo prosthesis for patients with a problematic amputation stump].

NARCIS (Netherlands)

Frolke, J.P.M.; Meent, H. van de

2010-01-01

Following lower limb amputation, quality of life is highly related to the ability to use a prosthetic limb. The conventional way to attach a prosthetic limb to the body is with a socket. Many patients experience serious discomfort wearing a conventional prosthesis because of pain, instability during

Metabolic cost of level-ground walking with a robotic transtibial prosthesis combining push-off power and nonlinear damping behaviors: preliminary results.

Science.gov (United States)

Yanggang Feng; Jinying Zhu; Qining Wang

2016-08-01

Recent advances in robotic technology are facilitating the development of robotic prostheses. Our previous studies proposed a lightweight robotic transtibial prosthesis with a damping control strategy. To improve the performance of power assistance, in this paper, we redesign the prosthesis and improve the control strategy by supplying extra push-off power. A male transtibial amputee subject volunteered to participate in the study. Preliminary experimental results show that the proposed prosthesis with push-off control improves energy expenditure by a percentage ranged from 9.72 % to 14.99 % for level-ground walking compared with the one using non-push-off control.

BODY IMAGE AND MENTAL REPRESENTATION IN TABLE TENNIS PLAYERS WHO DO VERSUS DO NOT USE A PROSTHESIS

OpenAIRE

Damian Jeraj; Lisa Musculus; Babett H. Lobinger

2017-01-01

The prosthesis that athletes use should take over the function of the missing limb. Playing table tennis without constraints is one exemplary goal. The question arose whether table tennis players who used a prosthesis and players who did not show similar body image values and mental representation of movements. Five matched pairs of active table tennis players (n = 10) completed a body image questionnaire. Additionally, the mental representation of a forehand table tennis serve was assessed. ...

Online Phase Detection Using Wearable Sensors for Walking with a Robotic Prosthesis

Directory of Open Access Journals (Sweden)

Maja Goršič

2014-02-01

Full Text Available This paper presents a gait phase detection algorithm for providing feedback in walking with a robotic prosthesis. The algorithm utilizes the output signals of a wearable wireless sensory system incorporating sensorized shoe insoles and inertial measurement units attached to body segments. The principle of detecting transitions between gait phases is based on heuristic threshold rules, dividing a steady-state walking stride into four phases. For the evaluation of the algorithm, experiments with three amputees, walking with the robotic prosthesis and wearable sensors, were performed. Results show a high rate of successful detection for all four phases (the average success rate across all subjects >90%. A comparison of the proposed method to an off-line trained algorithm using hidden Markov models reveals a similar performance achieved without the need for learning dataset acquisition and previous model training.

Walking on uneven terrain with a powered ankle prosthesis: A preliminary assessment.

Science.gov (United States)

Shultz, Amanda H; Lawson, Brian E; Goldfarb, Michael

2015-01-01

A successful walking gait with a powered prosthesis depends heavily on proper timing of power delivery, or push-off. This paper describes a control approach which provides improved walking on uneven terrain relative to previous work intended for use on even (level) terrain. This approach is motivated by an initial healthy subject study which demonstrated less variation in sagittal plane shank angle than sagittal plane ankle angle when walking on uneven terrain relative to even terrain. The latter therefore replaces the former as the control signal used to initiate push-off in the powered prosthesis described herein. The authors demonstrate improvement in consistency for several gait characteristics, relative to healthy, as well as controller characteristics with the new control approach, including a 50% improvement in the consistency of the percentage of stride at which push-off is initiated.

Wrist disarticulation of a deformed hand: appropriate prosthesis and the habilitation of a severely retarded young man.

Science.gov (United States)

Stimson, C; Morrison, H; Wakefield, W; Kiss, T; Lehneis, H R; Simons, A; Sverdlik, S S; Rotondo, M J

1984-05-01

A 24-year-old man, who was late attaining developmental milestones and tested in the severely mentally retarded range, had incurred third- and fourth-degree burns at 2.5 years that resulted in a deformed, anesthetic, and useless distal left upper limb. Following wrist disarticulation, he was fitted with a cosmetic prosthesis that he accepted enthusiastically. It permitted him to use his left upper limb as an effective assister. Attempts to wear and use a functional prosthesis were not successful because the bulbous stump was covered with abnormal skin that ulcerated whenever he wore the prosthesis. At present, he resides at home with his mother and has all self-care skills. He attends a day treatment program and helps his mother with household chores as well as neighborhood errands. The prognosis for continued functional improvement is good, even though he remains severely mentally retarded.

Residual standard deviation: Validation of a new measure of dual-task cost in below-knee prosthesis users.

Science.gov (United States)

Howard, Charla L; Wallace, Chris; Abbas, James; Stokic, Dobrivoje S

2017-01-01

We developed and evaluated properties of a new measure of variability in stride length and cadence, termed residual standard deviation (RSD). To calculate RSD, stride length and cadence are regressed against velocity to derive the best fit line from which the variability (SD) of the distance between the actual and predicted data points is calculated. We examined construct, concurrent, and discriminative validity of RSD using dual-task paradigm in 14 below-knee prosthesis users and 13 age- and education-matched controls. Subjects walked first over an electronic walkway while performing separately a serial subtraction and backwards spelling task, and then at self-selected slow, normal, and fast speeds used to derive the best fit line for stride length and cadence against velocity. Construct validity was demonstrated by significantly greater increase in RSD during dual-task gait in prosthesis users than controls (group-by-condition interaction, stride length p=0.0006, cadence p=0.009). Concurrent validity was established against coefficient of variation (CV) by moderate-to-high correlations (r=0.50-0.87) between dual-task cost RSD and dual-task cost CV for both stride length and cadence in prosthesis users and controls. Discriminative validity was documented by the ability of dual-task cost calculated from RSD to effectively differentiate prosthesis users from controls (area under the receiver operating characteristic curve, stride length 0.863, p=0.001, cadence 0.808, p=0.007), which was better than the ability of dual-task cost CV (0.692, 0.648, respectively, not significant). These results validate RSD as a new measure of variability in below-knee prosthesis users. Future studies should include larger cohorts and other populations to ascertain its generalizability. Copyright © 2016 Elsevier B.V. All rights reserved.

Engagement in activities revealing the body and psychosocial adjustment in adults with a trans-tibial prosthesis.

Science.gov (United States)

Donovan-Hall, M K; Yardley, L; Watts, R J

2002-04-01

The purpose of this study was to examine the effects of the appearance of a prosthesis on social behaviour, social discomfort and psychological well-being in eleven amputees taking delivery of a prosthesis with a silicone cover. Two new scales were developed: the 'Engagement in everyday activities involving revealing the body' (EEARB); and the 'Discomfort-Engagement in everyday activities involving revealing the body' (Discomfort-EEARB) scales. The psychometric properties of these scales were determined using a sample of 101 able-bodied adults. The Hospital Anxiety and Depression Scale and the Rosenberg Self-Esteem Scale were also used to measure psychological well-being in the amputee sample. The EEARB and Discomfort-EEARB proved to have good reliability and validity. Comparison of amputees' scores prior to receiving the silicone cosmesis with those of the able-bodied adults revealed significant behavioural limitations and social discomfort, associated with low self-esteem, anxiety and depression. There was a significant increase in amputees' scores three months afier taking delivery of their prosthesis, indicating that amputees reported engaging in more activities which involved revealing their body, and that they would feel more comfortable in situations which involved revealing the body. As the amputee sample available was small and self-selected, it is not possible to generalise these findings to the amputee population as a whole. However, since there is little previous research investigating the effects of the appearance of the prosthesis, these findings demonstrate the need for further research in this area.

Clinical, biomechanical and morphological assessment of anterior cruciate ligament Kevlar®-based artificial prosthesis in rabbit model.

Science.gov (United States)

de la Garza-Castro, Santiago; González-Rivera, Carlos E; Vílchez-Cavazos, Félix; Morales-Avalos, Rodolfo; Barrera-Flores, Francisco J; Elizondo-Omaña, Rodrigo E; Soto-Dominguez, Adolfo; Acosta-Olivo, Carlos; Mendoza-Lemus, Oscar F

2017-07-27

The aim of this study was to evaluate the clinical, biomechanical and morphological characteristics of a Kevlar®-based prosthetic ligament as a synthetic graft of the anterior cruciate ligament (ACL) in an experimental animal model in rabbits. A total of 27 knees of rabbits randomly divided into 3 groups (control, ACL excision and ACL replacement with a Kevlar® prosthesis) were analyzed using clinical, biomechanical and morphological tests at 6, 12 and 18 weeks postprocedure. The mean displacement in mechanical testing was 0.73 ± 0.06 mm, 1.58 ± 0.19 mm and 0.94 ± 0.20 mm for the control, ACL excision and ACL replacement with synthetic prosthesis groups, respectively. The results showed an improvement in the stability of the knee with the use of the Kevlar® synthetic prosthesis in the biomechanical testing (p0.05), between the replacement group and the control group. The histological study revealed a good morphological adaptation of the synthetic material to the knee. This study proposes a new animal model for the placement and evaluation of Kevlar®-based synthetic ACL implants. The studied prosthesis showed promising behavior in the clinical and biomechanical tests and in the histological analysis. This study lays the foundation for further basic and clinical studies of artificial ACL prostheses using this material.

78 FR 79308 - Dental Devices; Reclassification of Temporary Mandibular Condyle Prosthesis

Science.gov (United States)

2013-12-30

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 872 [Docket No. FDA-2012-N-1239] Dental Devices; Reclassification of Temporary Mandibular Condyle Prosthesis AGENCY... delegated to the Commissioner of Food and Drugs, 21 CFR part 872 is amended as follows: PART 872--DENTAL...

Evaluation of metal-polymeric fixed partial prosthesis using optical coherence tomography

Science.gov (United States)

Sinescu, C.; Negrutiu, M. L.; Duma, V. F.; Marcauteanu, C.; Topala, F. I.; Rominu, M.; Bradu, A.; Podoleanu, A. Gh.

2013-11-01

Metal-Polymeric fixed partial prosthesis is the usual prosthetic treatment for many dental patients. However, during the mastication the polymeric component of the prosthesis is fractured and will be lost. This fracture is caused by the material defects or by the fracture lines trapped inside the esthetic components of the prosthesis. This will finally lead to the failure of the prosthetic treatment. Nowadays, there is no method of identification and forecast for the materials defects of the polymeric materials. The aim of this paper is to demonstrate the capability of Optical Coherence Tomography (OCT) as a non-invasive clinical method that can be used for the evaluation of metal-polymeric fixed partial prostheses. Twenty metal-polymeric fixed partial prostheses were used for this study. The esthetic component of the prostheses has been Adoro (Ivoclar). Optical investigations of the metal prostheses have revealed no material defects or fracture lines. All the prostheses were temporary cemented in the oral cavities of the patients for six month. The non-invasive method used for the investigations was OCT working in Time Domain mode at 1300 nm. The evaluations of the prostheses were performed before and after their cementation in the patient mouths. All the imagistic results were performed in 2D and than in 3D, after the reconstruction. The results obtained after the OCT evaluation allowed for the identification of 4 metal-polymeric fixed partial prostheses with material defects immediately after finishing the technological procedures. After 6 month in the oral environment other 3 fixed partial prostheses revealed fracture lines. In conclusion, OCT proved to be a valuable tool for the noninvasive evaluation of the metal-polymeric fixed partial prostheses.

Lumbar subtotal corpectomy non-fusion model produced using a novel prosthesis.

Science.gov (United States)

Liu, Jiantao; Zhang, Feng; Gao, Zhengchao; Li, Yuhuan; Niu, Binbin; He, Xijing

2017-11-01

In this study, we aimed to design a movable artificial lumbar complex (MALC) prosthesis for non-fusion reconstruction after lumbar subtotal corpectomy and to establish an in vitro anterolateral lumbar corpectomy non-fusion model for evaluating the biomechanical stability, preservation of segment movements and influence on adjacent inter-vertebral movements of this prosthesis. Imaging was performed on a total of 26 fresh goat lumbar spine specimens to determine which of the specimens did not meet the requirements (free of deformity and fractures); the residual specimens were randomly divided into an intact group, a fusion group and a non-fusion group. Bone mineral density (BMD) was tested and compared among the three groups. Biomechanical testing was conducted to obtain the range of motion (ROM) in flexion-extension, lateral bending at L2-3, L3-4 and L4-5 and axial rotation at L2-5 in the three groups. Two specimens were excluded due to vertebral fractures. BMD showed no statistical significance among three groups (P > 0.05). The stability of the prosthesis did not differ significantly during flexion, extension, and lateral bending at L2-3, L3-4, and L4-5 and axial torsion at L2-5 between the intact group and the non-fusion group (P > 0.05). Segment movements of the specimens in the non-fusion group revealed significantly decreased L2-3 ROM and significantly increased L3-4 and L4-5 ROM in flexion and lateral bending compared with the fusion group (P inter-vertebral spaces. However, additional studies, including in vivo animal experiments as well as biocompatibility and biomechanical tests of human body specimens are needed.

On the analysis of using 3-coil wireless power transfer system in retinal prosthesis.

Science.gov (United States)

Bai, Shun; Skafidas, Stan

2014-01-01

Designing a wireless power transmission system(WPTS) using inductive coupling has been investigated extensively in the last decade. Depending on the different configurations of the coupling system, there have been various designing methods to optimise the power transmission efficiency based on the tuning circuitry, quality factor optimisation and geometrical configuration. Recently, a 3-coil WPTS was introduced in retinal prosthesis to overcome the low power transferring efficiency due to low coupling coefficient. Here we present a method to analyse this 3-coil WPTS using the S-parameters to directly obtain maximum achievable power transferring efficiency. Through electromagnetic simulation, we brought a question on the condition of improvement using 3-coil WPTS in powering retinal prosthesis.

EFFECTS OF DEXAMETHASONE AND PHENIRAMINE MALEATE ON HEMODYNAMIC AND RESPIRATORY PARAMETERS AFTER CEMENTATION IN CEMENTED PARTIAL HIP PROSTHESIS.

Science.gov (United States)

Yektaş, Abdulkadir; Gümüş, Funda; Totoz, Tolga; Gül, Nurten; Erkalp, Kerem; Alagöl, Ayşin

2015-02-01

To prevent hemodynamic and respiratory changes that are likely to occur during cementation in partial hip prosthesis by prophylactic use of pheniramine maleate and dexamethasone. The study included 40 patients aged between 60 and 85 years with an American Society ofAnesthesiologists (ASA) grade of II-III who underwent partial hip prosthesis. Just after spinal anesthesia, 4 mL normal saline was pushed in patients in Group S, whereas 45.5 mg pheniramine maleate and 8 mg dexamethasone mixture was pushed intravenously in a total volume of 4 mL in patients in Group PD. Amounts of atropine and adrenaline administered after cementation were significantly higher in Group S than in Group PD (P pheniramine maleate and dexamethasone in partial hip prosthesis led to an increase in SpO2 value and a decrease in the utilization of adrenaline and atropine after cementation.

A Medical Wireless Measurement System for Hip Prosthesis Loosening Detection Based on Vibration Analysis

Directory of Open Access Journals (Sweden)

Sebastian Sauer

2013-01-01

Full Text Available Vibration analysis is a promising approach in order to detect early hip prosthesis loosening, with the potential to extend the range of diagnostic tools currently available in clinical routine. Ongoing research efforts and developments in the area of multi-functional implants, which integrate sensors, wireless power supply, communication and signal processing, provide means to obtain valuable in vivo information otherwise not available. In the current work a medical wireless measurement system is presented, which is integrated in the femoral head of a hip prosthesis. The passive miniaturized system includes a 3-axis acceleration sensor and signal pre-processing based on a lock-in amplifier circuit. Bidirectional data communication and power supply is reached through inductive coupling with an operating frequency of 125 kHz in accordance with the ISO 18000-2 protocol standard. The system allows the acquisition of the acceleration frequency response of the femur-prosthesis system between 500 to 2500 Hz. Applied laboratory measurements with system prototypes on artificial bones and integrated prostheses demonstrate the feasibility of the measurement system approach, clearly showing differences in the vibration behavior due to an implant loosening. In addition a possibility to evaluate the non-linear mechanic system behavior is presented.

Patient satisfaction with maxillofacial prosthesis. Literature review.

Science.gov (United States)

Goiato, Marcelo Coelho; Pesqueira, Aldiéris Alves; Ramos da Silva, Cristina; Gennari Filho, Humberto; Micheline Dos Santos, Daniela

2009-02-01

Obturators and facial prostheses are important not only in rehabilitation and aesthetics, but also in patient re-socialisation. The level of reintegration is directly related to the degree of satisfaction with rehabilitation. So, the maxillofacial prosthetics must provide patient satisfaction during treatment. This study aimed to search information in database and conduct a literature review on patient satisfaction with maxillofacial prosthesis. The problems experienced by these patients may decrease when specialists keep the patient on regular inspection. Rehabilitation through alloplasty or prosthetic restoration provides satisfactory conditions in aesthetics and well-being and reinstates individuals in familial and social environment.

A predictive model for early mortality after surgical treatment of heart valve or prosthesis infective endocarditis. The EndoSCORE.

Science.gov (United States)

Di Mauro, Michele; Dato, Guglielmo Mario Actis; Barili, Fabio; Gelsomino, Sandro; Santè, Pasquale; Corte, Alessandro Della; Carrozza, Antonio; Ratta, Ester Della; Cugola, Diego; Galletti, Lorenzo; Devotini, Roger; Casabona, Riccardo; Santini, Francesco; Salsano, Antonio; Scrofani, Roberto; Antona, Carlo; Botta, Luca; Russo, Claudio; Mancuso, Samuel; Rinaldi, Mauro; De Vincentiis, Carlo; Biondi, Andrea; Beghi, Cesare; Cappabianca, Giangiuseppe; Tarzia, Vincenzo; Gerosa, Gino; De Bonis, Michele; Pozzoli, Alberto; Nicolini, Francesco; Benassi, Filippo; Rosato, Francesco; Grasso, Elena; Livi, Ugolino; Sponga, Sandro; Pacini, Davide; Di Bartolomeo, Roberto; De Martino, Andrea; Bortolotti, Uberto; Onorati, Francesco; Faggian, Giuseppe; Lorusso, Roberto; Vizzardi, Enrico; Di Giammarco, Gabriele; Marinelli, Daniele; Villa, Emmanuel; Troise, Giovanni; Picichè, Marco; Musumeci, Francesco; Paparella, Domenico; Margari, Vito; Tritto, Francesco; Damiani, Girolamo; Scrascia, Giuseppe; Zaccaria, Salvatore; Renzulli, Attilio; Serraino, Giuseppe; Mariscalco, Giovanni; Maselli, Daniele; Foschi, Massimiliano; Parolari, Alessandro; Nappi, Giannantonio

2017-08-15

The aim of this large retrospective study was to provide a logistic risk model along an additive score to predict early mortality after surgical treatment of patients with heart valve or prosthesis infective endocarditis (IE). From 2000 to 2015, 2715 patients with native valve endocarditis (NVE) or prosthesis valve endocarditis (PVE) were operated on in 26 Italian Cardiac Surgery Centers. The relationship between early mortality and covariates was evaluated with logistic mixed effect models. Fixed effects are parameters associated with the entire population or with certain repeatable levels of experimental factors, while random effects are associated with individual experimental units (centers). Early mortality was 11.0% (298/2715); At mixed effect logistic regression the following variables were found associated with early mortality: age class, female gender, LVEF, preoperative shock, COPD, creatinine value above 2mg/dl, presence of abscess, number of treated valve/prosthesis (with respect to one treated valve/prosthesis) and the isolation of Staphylococcus aureus, Fungus spp., Pseudomonas Aeruginosa and other micro-organisms, while Streptococcus spp., Enterococcus spp. and other Staphylococci did not affect early mortality, as well as no micro-organisms isolation. LVEF was found linearly associated with outcomes while non-linear association between mortality and age was tested and the best model was found with a categorization into four classes (AUC=0.851). The following study provides a logistic risk model to predict early mortality in patients with heart valve or prosthesis infective endocarditis undergoing surgical treatment, called "The EndoSCORE". Copyright © 2017. Published by Elsevier B.V.

Prototype design and realization of an innovative energy efficient transfemoral prosthesis

NARCIS (Netherlands)

Ünal, Ramazan; Behrens, Sebastiaan Maria; Behrens, S.M.; Carloni, Raffaella; Hekman, Edsko E.G.; Stramigioli, Stefano; Koopman, Hubertus F.J.M.

In this paper, we present the prototype realization of the conceptual design of a fully-passive transfemoral prosthesis. The working principle has been inspired by the power flow in human gait so to achieve an energy efficient device. The main goal of this paper is to validate the concept by

Temporomandibular Joint Prosthesis - 3D-CT Reconstruction before and after Treatment

Czech Academy of Sciences Publication Activity Database

Feltlová, E.; Dostálová, T.; Kašparová, M.; Daněk, J.; Hliňáková, P.; Hubáček, M.; Nedoma, Jiří

2010-01-01

Roč. 6, č. 1 (2010), s. 15-19 ISSN 1801-5603 Institutional research plan: CEZ:AV0Z10300504 Keywords : dentistry * maxillofacial surgery * partial TMJ prosthesis * three-dimensional computed tomography * magnetic resonance imaging * temporomandibular joint Subject RIV: BA - General Mathematics http://www.ejbi.cz/articles/201012/50/1.html

Monitoring the evolution of boron doped porous diamond electrode on flexible retinal implant by OCT and in vivo impedance spectroscopy

International Nuclear Information System (INIS)

Hébert, Clément; Cottance, Myline; Degardin, Julie; Scorsone, Emmanuel; Rousseau, Lionel; Lissorgues, Gaelle; Bergonzo, Philippe; Picaud, Serge

2016-01-01

Nanocrystalline Boron doped Diamond proved to be a very attractive material for neural interfacing, especially with the retina, where reduce glia growth is observed with respect to other materials, thus facilitating neuro-stimulation over long terms. In the present study, we integrated diamond microelectrodes on a polyimide substrate and investigated their performances for the development of neural prosthesis. A full description of the microfabrication of the implants is provided and their functionalities are assessed using cyclic voltammetry and electrochemical impedance spectroscopy. A porous structure of the electrode surface was thus revealed and showed promising properties for neural recording or stimulation. Using the flexible implant, we showed that is possible to follow in vivo the evolution of the electric contact between the diamond electrodes and the retina over 4 months by using electrochemical impedance spectroscopy. The position of the implant was also monitored by optical coherence tomography to corroborate the information given by the impedance measurements. The results suggest that diamond microelectrodes are very good candidates for retinal prosthesis. - Highlights: • Microfabrication of porous diamond electrode on flexible retinal implant • Electrochemical characterization of microelectrode for neural interfacing • In vivo impedance spectroscopy of retinal tissue

Monitoring the evolution of boron doped porous diamond electrode on flexible retinal implant by OCT and in vivo impedance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Hébert, Clément, E-mail: clement.hebert@icn2.cat [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette 91191 (France); Cottance, Myline [Université Paris-Est, ESYCOM-ESIEE Paris, Noisy le Grand (France); Degardin, Julie [INSERM, U968, Institut de la Vision, Paris (France); Scorsone, Emmanuel [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette 91191 (France); Rousseau, Lionel; Lissorgues, Gaelle [Université Paris-Est, ESYCOM-ESIEE Paris, Noisy le Grand (France); Bergonzo, Philippe [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette 91191 (France); Picaud, Serge [INSERM, U968, Institut de la Vision, Paris (France)

2016-12-01

Nanocrystalline Boron doped Diamond proved to be a very attractive material for neural interfacing, especially with the retina, where reduce glia growth is observed with respect to other materials, thus facilitating neuro-stimulation over long terms. In the present study, we integrated diamond microelectrodes on a polyimide substrate and investigated their performances for the development of neural prosthesis. A full description of the microfabrication of the implants is provided and their functionalities are assessed using cyclic voltammetry and electrochemical impedance spectroscopy. A porous structure of the electrode surface was thus revealed and showed promising properties for neural recording or stimulation. Using the flexible implant, we showed that is possible to follow in vivo the evolution of the electric contact between the diamond electrodes and the retina over 4 months by using electrochemical impedance spectroscopy. The position of the implant was also monitored by optical coherence tomography to corroborate the information given by the impedance measurements. The results suggest that diamond microelectrodes are very good candidates for retinal prosthesis. - Highlights: • Microfabrication of porous diamond electrode on flexible retinal implant • Electrochemical characterization of microelectrode for neural interfacing • In vivo impedance spectroscopy of retinal tissue.

Computer design synthesis of a below knee-Syme prosthesis

Science.gov (United States)

Elangovan, P. T.; Ghista, D. N.; Alwar, R. S.

1979-01-01

A detailed design synthesis analysis of the BK Syme prosthesis is provided, to determine the socket's cutout orientation size and shape, cutout fillet shape, socket wall thickness distribution and the reinforced fiber distribution in the socket wall, for a minimally stressed structurally safe lightweight prosthesis. For analysis purposes, the most adverse socket loading is obtained at the push-off stage of gait; this loading is idealized as an axial in-plane loading on the bottom edge of the circular cylindrical socket shell whose top edge is considered fixed. Finite element stress analysis of the socket shell (with uniform and graded wall thickness) are performed for various orientations of the cutout and for various types of corner fillets. A lateral cutout with a streamline fillet is recommended. The wall material (i.e., thickness) distribution is determined so as to minimize the stresses, while ensuring that the wall material's stress limits are not exceeded. For such a maximally stressed lightweight socket shell, the panels in the neighborhood of the cutout are checked to ensure that they do not buckle under their acquired stresses. A fiber-reinforced laminated composite socket shell is also analyzed in order to recommend optimum variables in orientations and densities of reinforcing fibers.

Learning to use a body-powered prosthesis : changes in functionality and kinematics

NARCIS (Netherlands)

Huinink, Laura H. B.; Bouwsema, Hanneke; Plettenburg, Dick H.; van der Sluis, Corry K.; Bongers, Raoul M.

2016-01-01

Background: Little is known about action-perception learning processes underlying prosthetic skills in body-powered prosthesis users. Body-powered prostheses are controlled through a harness connected by a cable that might provide for limited proprioceptive feedback. This study aims to test transfer

Learning to use a body-powered prosthesis : changes in functionality and kinematics

NARCIS (Netherlands)

Huinnk, L.H.B.; Bouwsema, H.; Plettenburg, D.H.; van der Sluis, C.K.; Bongers, R.M.

2016-01-01

Background: Little is known about action-perception learning processes underlying prosthetic skills in body-powered prosthesis users. Body-powered prostheses are controlled through a harness connected by a cable that might provide for limited proprioceptive feedback. This study aims to test

The psychosocial benefits of secondary hydroxyapatite orbital implant insertion and prosthesis wearing for patients with anophthalmia.

Science.gov (United States)

Wang, Junming; Zhang, Hong; Chen, Wei; Li, Guigang

2012-01-01

Anophthalmia is associated with a range of psychosocial difficulties and hydroxyapatite orbital implant insertion and prosthesis wearing is the predominant rehabilitation therapy for anophthalmia. However, few articles have compared preoperative and postoperative psychosocial outcomes using standardized questionnaires. This study aimed to investigate the psychosocial benefits of hydroxyapatite orbital implant insertion and prosthesis wearing in this patient population. In all, 36 participants were tested preoperatively and 6-months postoperatively using standardized measures of anxiety and depression (Hospital Anxiety and Depression Scale), social anxiety and social avoidance (Derriford Appearance Scale-Short Form), and quality of life (World Health Organization Quality of Life Scale-Short Form). Before treatment, levels of depression were comparable with population norms; however, levels of general anxiety were slightly raised, levels of social anxiety, social avoidance, and quality of life were significantly poorer than population norms. Treatment resulted in significant improvement in psychosocial adjustment with improvements in all study variables for the participant group as a whole. Hydroxyapatite orbital implant insertion and prosthesis wearing offers significant improvements in psychological and physical functioning for patients with anophthalmia.

Complicações decorrentes do uso de prótese vocal Complications in consequence of the vocal prosthesis use

Directory of Open Access Journals (Sweden)

Leonardo de Souza Kruschewsky

2002-01-01

Full Text Available INTRODUÇÃO: Desde a primeira laringectomia total, realizada em 1873, já se tem registro do interesse em se desenvolver e recuperar a comunicabilidade verbal desses pacientes. Porém grandes progressos foram observados depois de 1979, quando se pode contar com próteses traqueoesofágicas. Mesmo sendo um enorme progresso, as próteses vocais geram complicações. OBJETIVO: Avaliar as complicações com o emprego de próteses vocais e relaciona-las com fatores clínicos e tipo de prótese. MÉTODOS: Dez pacientes submetidos a laringectomia total portando prótese fonatória foram acompanhados no serviço de Cirurgia de Cabeça e Pescoço do HCRP-FMRP-USP buscando-se registrar as complicações e relaciona-las com fatores clínicos e tipo de prótese. RESULTADOS: Foram registrados: vazamento de saliva e/ou dieta da faringe para a traquéia, infecção fungica, ausência de função da prótese e esses achados foram quantificados avaliando-se os efeitos da radioterapia e do tipo de prótese usada. CONCLUSÃO: A prótese vocal apresenta dificuldades e complicações operacionais que merecem atenção e mais estudos são necessários para se ter o perfil mais completo destes aspectos.INTRODUCTION: Since 1873 when the first total laryngectomy was performed there is a scientific interest in develop and recover patients' verbal comunication. Great successes were done after 1979, that permitted the tracheoesophagical prosthesis be a reality. Even being a special conquest the vocal prosthesis has its complications. AIM: To evaluate its complications registered with the vocal prosthesis use and its relation with patients' clinical aspects and the prosthesis kind. METHODS: Ten total laryngectomised patients from the HCRP-FMRP-USP, Head and Neck ambulatory, were followed to complications manifestations with the prosthesis use. RESULTS: Complications as saliva and/or diet passage from the pharynx to the trachea, fungal infection, prosthesis dysfunction were

Electron microscopy study of a vascular prosthesis destructed in vivo reveals fractures in Dacron fibers.

Science.gov (United States)

Woźniak, Witold; Olszewski, Wojciech; Górski, Grzegorz

2016-02-01

The genuine destruction of a synthetic prosthesis wall, as a late complication of vascular surgery, is extremely rare. We report a case of a 64-year-old male who had his 12-year-old femoropopliteal synthetic graft explanted due to two large pseudoaneurysms in the middle section of the graft. Microscopic evaluation demonstrated the areas of focal thinning along the entire prosthesis wall, with "foreign body" type reaction in the adjacent connective tissue. Transmission electron microscopy showed longitudinal fractures of Dacron fibers interposed with cellular structures, suggesting that destruction must have taken place significantly earlier. The problems of limited graft durability and graft surveillance are discussed. © The Author(s) 2015.

A Patient-Matched Entire First Metacarpal Prosthesis in Treatment of Giant Cell Tumor of Bone

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Thipachart Punyaratabandhu

2017-01-01

Full Text Available Giant cell tumor of the bones occurring in the first metacarpals frequently requires entire metacarpal resection due to the aggressive nature and high rate of recurrence. Bone reconstruction can be performed with autogenous bone grafts. Here we describe a new technique of reconstruction using a patient-matched three-dimensional printed titanium first metacarpal prosthesis. This prosthesis has a special design for ligament reconstruction in the proximal and distal portions. Good hand function and aesthetic appearance were maintained at a 24-month follow-up visit. This reconstructive technique can avoid donor-site complications and spare the autogenous bone grafts for revision options.

Clinical and Radiographic Outcomes of Unipolar and Bipolar Radial Head Prosthesis in Patients with Radial Head Fracture: A Systemic Review and Meta-Analysis.

Science.gov (United States)

Chen, Hongwei; Wang, Ziyang; Shang, Yongjun

2018-06-01

To compare clinical outcomes of unipolar and bipolar radial head prosthesis in the treatment of patients with radial head fracture. Medline, Cochrane, EMBASE, Google Scholar databases were searched until April 18, 2016 using the following search terms: radial head fracture, elbow fracture, radial head arthroplasty, implants, prosthesis, unipolar, bipolar, cemented, and press-fit. Randomized controlled trials, retrospective, and cohort studies were included. The Mayo elbow performance score (MEPS), disabilities of the arm, shoulder, and hand (DASH) score, radiologic assessment, ROM, and grip strength following elbow replacement were similar between prosthetic devices. The pooled mean excellent/good ranking of MEPS was 0.78 for unipolar and 0.73 for bipolar radial head arthroplasty, and the pooled mean MEPS was 86.9 and 79.9, respectively. DASH scores for unipolar and bipolar prosthesis were 19.0 and 16.3, respectively. Range of motion outcomes were similar between groups, with both groups have comparable risk of flexion arc, flexion, extension deficit, rotation arc, pronation, and supination (p values bipolar prosthesis). However, bipolar radial head prosthesis was associated with an increased chance of heterotopic ossification and lucency (p values ≤0.049) while unipolar prosthesis was not (p values ≥0.088). Both groups had risk for development of capitellar osteopenia or erosion/wear (p values ≤0.039). Unipolar and bipolar radial head prostheses were similar with respect to clinical outcomes. Additional comparative studies are necessary to further compare different radial head prostheses used to treat radial head fracture.

Total hip arthroplasty using a short-stem prosthesis: restoration of hip anatomy.

Science.gov (United States)

Amenabar, Tomas; Marimuthu, Kanniraj; Hawdon, Gabrielle; Gildone, Alessandro; McMahon, Stephen

2015-04-01

To evaluate hip parameters such as vertical centre of rotation (VCR), horizontal centre of rotation (HCR), femoral offset, and leg length after total hip arthroplasty (THA) using the Nanos short-stem prosthesis. Medical records of 73 men and 74 women aged 25 to 92 (mean, 63) years who underwent THA using the Nanos short-stem prosthesis by a single surgeon were reviewed. Prior to the surgery, the optimal cup and stem size, head length, and level of the neck osteotomy were determined using radiographs. Intra-operatively, the leg length and femoral offset were checked, and the level of neck resection and head length were adjusted. VCR, HCR, femoral offset, and leg length of the operated and contralateral sides were compared. Functional outcomes were assessed using the Harris Hip Score (HHS). Compared with the normal contralateral hips, the operated hips had a mean increase of 0.4 mm in VCR (p=0.032), a mean decrease of 1.4 mm in HCR (p=0.027), a mean increase of 0.6 mm in femoral offset (p=0.043), and a mean increase of 0.36 mm in leg length (p=0.035). For these respective parameters, the difference between the normal contralateral side and the operated side was within 5 mm in 89%, 80%, 71%, and 96% of patients. The HHS improved from a mean of 53 to 91 at one year (pNanos short-stem prosthesis enabled restoration of hip anatomy (VCR, HCR, femoral offset, and leg length).

Treatment of sharp mandibular alveolar process with hybrid prosthesis

OpenAIRE

Sukaedi, Sukaedi; Djulaeha, Eha

2010-01-01

Background: Losing posterior teeth for a long time would occasionally lead to the sharpening of alveolar process. The removable partial denture usually have problems when used during mastication, because of the pressure on the mucosa under the alveolar ridge. Purpose: The purpose of this case report was to manage patients with sharp mandibular alveolar process by wearing hybrid prosthesis with extra coronal precision attachment retention and soft liner on the surface base beneath the removabl...

A novel knee prosthesis model of implant-related osteo- myelitis in rats

DEFF Research Database (Denmark)

Søe, Niels H.; Jensen, Nina Vendel; Nürnberg, Birgit Meinecke

2012-01-01

There have been numerous reports of animal models of osteomyelitis. Very few of these have been prosthesis models that imitate human conditions. We have developed a new rat model of implant-related osteomyelitis that mimics human osteomyelitis, to investigate the pathology of infection after...

Analysis of failure of voice production by a sound-producing voice prosthesis

NARCIS (Netherlands)

van der Torn, M.; van Gogh, C.D.L.; Verdonck-de Leeuw, I M; Festen, J.M.; Mahieu, H.F.

OBJECTIVE: To analyse the cause of failing voice production by a sound-producing voice prosthesis (SPVP). METHODS: The functioning of a prototype SPVP is described in a female laryngectomee before and after its sound-producing mechanism was impeded by tracheal phlegm. This assessment included:

Rapid proto typing of dental prosthesis by means of a feldspathic glass composite mixed with muscovite mica via CAD/CAM

International Nuclear Information System (INIS)

Garcia Junior, E.S.; Gomes Junior, G.G.; Fonseca, M.D.; Moraes, E.E.S.; Ogasawara, T.

2010-01-01

The work consists in the use and integration of CAD/CAM tools as a process of design and manufacture of a rapid prototyping of dental prosthesis by machining using a CNC milling machine. The material machined to obtain the dental prosthesis were cylindrical blocks of a Feldspathic glass composite mixed with muscovite mica in various percentages (15%, 40% and 80%), which was resigned under biaxial pressing and sintered in vacuum at temperatures from 800 to 1100 deg C. The composite was characterized by XRD and SEM. The results show that increasing the crystallization of leucite is consequent to the temperature increase, and that the use of CAD/CAM system using a CNC milling machine is feasible to obtain dental prosthesis. (author)

Semi-rigid penile prosthesis as a salvage management of idiopathic ischemic stuttering priapism

Directory of Open Access Journals (Sweden)

Faddan AA

2015-09-01

Full Text Available Amr A Faddan, Alexey V Aksenov, Carsten M Naumann, Klaus P Jünemann, Daniar K Osmonov Department of Urology and Pediatric Urology, University Hospital Schleswig-Holstein, Kiel, Germany Introduction: Priapism is the persistent erection resulting from dysfunction of the mechanisms that regulate penile swelling, stiffness, and sagging. It is a full or partial erection that persists for a period more than 4 hours beyond sexual stimulation and/or orgasm or is unrelated to sexual stimulation. Ischemic priapism should be managed in a step-by-step fashion. Objective: To demonstrate step-by-step management of stuttering refractory ischemic priapism. We report a case of stuttering refractory ischemic priapism. Moreover, we reviewed different approaches to priapism management in the literature. Case presentation: A 53-year-old male presented with a painful erection of 29 hours’ duration, probably caused by consumption of alcohol. The penile blood gas showed a pH of 7.08, PCO2 of 75 mmHg and PO2 of 39 mmHg. Aspiration was followed by irrigation of an α-adrenergic, Winter and T-shunt operations were preformed, and finally a semi-rigid penile prosthesis was implanted to overcome the refractory stuttering ischemic priapism. Conclusion: In case of stuttering refractory ischemic priapism, immediate implantation of a penile prosthesis is a simple and effective procedure that manages both the acute episode and the inevitable erectile dysfunction that would otherwise occur, while preserving penile length. Keywords: priapism, stuttering priapism, shunting operation, penile prosthesis 

Transcatheter aortic valve prosthesis surgically replaced 4 months after implantation

DEFF Research Database (Denmark)

Thyregod, Hans Gustav; Lund, Jens Teglgaard; Engstrøm, Thomas

2010-01-01

Transcatheter aortic valve implantation is a new and rapidly evolving treatment option for high-risk surgical patients with degenerative aortic valve stenosis. Long-term results with these new valve prostheses are lacking, and potential valve dysfunction and failure would require valve replacemen....... We report the first case of surgical valve replacement in a patient with a dysfunctional transcatheter-implanted aortic valve prosthesis 4 months after implantation....

Missing facial parts computed by a morphable model and transferred directly to a polyamide laser-sintered prosthesis: an innovation study.

Science.gov (United States)

Mueller, A A; Paysan, P; Schumacher, R; Zeilhofer, H-F; Berg-Boerner, B-I; Maurer, J; Vetter, T; Schkommodau, E; Juergens, P; Schwenzer-Zimmerer, K

2011-12-01

Mirroring of missing facial parts and rapid prototyping of templates have become widely used in the manufacture of prostheses. However, mirroring is not applicable for central facial defects, and the manufacture of a template still requires labour-intensive transformation into the final facial prosthesis. We have explored innovative techniques to meet these remaining challenges. We used a morphable model of a face for the reconstruction of missing facial parts that did not have mirror images, and skin-coloured polyamide laser sintering for direct manufacture of the prosthesis. From the knowledge gleaned from a data set of 200 coloured, three-dimensional scans, we generated a missing nose that was statistically compatible with the remaining parts of the patient's face. The planned prosthesis was manufactured directly from biocompatible skin-coloured polyamide powder by selective laser sintering, and the prosthesis planning system produced a normal-looking reconstruction. The polyamide will need adjustable colouring, and we must be able to combine it with a self-curing resin to fulfil the requirements of realistic permanent use. Copyright © 2011 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

An Adult Patient with Pneumonia Due to Aspiration of Dental Prosthesis

Directory of Open Access Journals (Sweden)

Samil Gunay

2014-03-01

Full Text Available In patients with a new and suddenly beginning of bronchial asthma and repetitive respiratory infection, one should consider the possibility of obstruction by a foreign body. In this case we present a male patient with pneumonia due to aspiration of dental prosthesis. A 32-year-old man presented with a 4-month history of dyspnea, chest pain and new    compliants of diaphoresis and fever persistend despite of antibiotic treatment. Then the patient consultated to our chest surgery department. After the physical examination of patient we made the fiberoptic  flexible bronchoscopy according to the uncertain opasity seen in the chest radiography. Later in the operating room, with the patient under general anesthesia, we extracted the aspirated foreign body, dental prosthesis, by rigid bronchoscopy. We should think about the possibility of foreign body aspiration for the patients with suddenly beginning of the complaints such as, bronchial asthma, repetitive respiratory infection, diaphoresis, chest pain and fever. Sometimes people hides the true anamnesis because of be ashamed or amnesia.

21 CFR 888.3400 - Hip joint femoral (hemi-hip) metallic resurfacing prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metallic resurfacing... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3400 Hip joint femoral (hemi-hip) metallic resurfacing prosthesis. (a) Identification. A hip joint femoral (hemi-hip...

21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint (hemi-hip) acetabular metal cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3370 Hip joint (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip) acetabular...

21 CFR 888.3350 - Hip joint metal/polymer semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal/polymer semi-constrained cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3350 Hip joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/polymer semi...

21 CFR 888.3300 - Hip joint metal constrained cemented or uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal constrained cemented or uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3300 Hip joint metal constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal constrained...

Supracondylar correction osteotomy to prevent repetitive posterior dislocation of a hip prosthesis

NARCIS (Netherlands)

Haverkamp, D.; Marti, R. K.

2008-01-01

Recurrent dislocation of a total hip prosthesis can be a challenging and often disappointing problem. This case report describes a 78-year-old woman who had recurrent posterior dislocations of a revision total hip replacement (THR) that occurred on flexion and internal rotation of the hip. The

21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral (hemi-knee...

21 CFR 888.3120 - Ankle joint metal/polymer non-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ankle joint metal/polymer non-constrained cemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3120 Ankle joint metal/polymer non-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer non...

Online human training of a myoelectric prosthesis controller via actor-critic reinforcement learning.

Science.gov (United States)

Pilarski, Patrick M; Dawson, Michael R; Degris, Thomas; Fahimi, Farbod; Carey, Jason P; Sutton, Richard S

2011-01-01

As a contribution toward the goal of adaptable, intelligent artificial limbs, this work introduces a continuous actor-critic reinforcement learning method for optimizing the control of multi-function myoelectric devices. Using a simulated upper-arm robotic prosthesis, we demonstrate how it is possible to derive successful limb controllers from myoelectric data using only a sparse human-delivered training signal, without requiring detailed knowledge about the task domain. This reinforcement-based machine learning framework is well suited for use by both patients and clinical staff, and may be easily adapted to different application domains and the needs of individual amputees. To our knowledge, this is the first my-oelectric control approach that facilitates the online learning of new amputee-specific motions based only on a one-dimensional (scalar) feedback signal provided by the user of the prosthesis. © 2011 IEEE

The Role of Prosthesis Spacer for Ocular Prostheses.

Science.gov (United States)

Figueiredo, Luiza Alencar De Andrade; Sampaio, Aline Araújo; Souza, Samilly Evangelista; Ferreira, Fernando José Rigolin; Buzzá, Edmur Pereira; Rizzatti-Barbosa, Celia Marisa

2017-06-01

Eye defects can lead to emotional, psychological, and social changes, impacting negatively the quality of life of the patient. When these structures cannot be satisfactorily repaired by reconstructive surgery, the prosthetic rehabilitation is the better treatment option to restore lost ocular anatomy and promote the social integration of the individual. The aim of this clinical report is to report and discuss a case of ocular prosthesis confection eviscerated patient with opening limitation eyelid and shortening of the distance between palpebral commissure, to obtain a more natural and comfortable to the patient ocular rehabilitation.

SU-F-T-374: Dosimetric Effects of Irradiation Through a Bilateral Hip Prosthesis in a MRI Linac

International Nuclear Information System (INIS)

Wronski, M; Sarfehnia, A; Sahgal, A; Keller, B; Ahmad, S

2016-01-01

Purpose: To evaluate the interface effects when irradiating through a hip prosthesis in the presence of an orthogonal 1.5 T magnetic field using Monte Carlo simulations. Methods: A 20×20×38 cm virtual phantom with two 5×5×5 cm sections of bilateral titanium hip prosthesis was created in GPU-based Monte Carlo (MC) algorithm (GPUMCD, Elekta AB, Stockholm Sweden). The lateral prosthesis spacing was based on a representative patient CT scan. A treatment SAD of 143.5 cm was chosen, corresponding to the Elekta AB MRI Linac and the beam energy distribution was sampled from a histogram representing the true MRI Linac spectrum. A magnetic field of 1.5 T was applied perpendicular to the plane of irradiation. Dose was calculated, in voxels of side 1 mm, for 2×2, 5×5, and 10×10 cm treatment field sizes with normal beam incidence (gantry at 90° or 270°) and at 5° and 10° from normal, representing the range of incidence through the bilateral prosthesis. Results: With magnetic field ON (B-On) and normal beam incidence the backscatter dose at the interfaces of proximal and distal implants is reduced for all the field sizes compared to the magnetic field OFF (B-Off) case. The absolute reduction in doses at the interface was in the range of 12.93% to 13.16% for the proximal implant and 13.57% to 16.12% for the distal implant. Similarly for the oblique incidences of 5o and 10o the dose in the plane adjacent to the prosthetic implants is lower when the magnetic field is ON. Conclusion: The dosimetric effects of irradiating through a hip prosthesis in the presence of a transverse magnetic field have been determined using MC simulation. The backscatter dose reduction translates into significantly lower hot spots at the prosthetic interfaces, which are otherwise substantially high in the absence of the magnetic field. This project was supported through funding provided by ElektaTM.

CLINICAL AND FUNCTIONAL ASSESSMENT OF THE BIOLOGICAL PROSTHESIS “ASPIRE” FOR SURGICAL CORRECTION OF MITRAL VALVE DISEASE

Directory of Open Access Journals (Sweden)

S. G. Esin

2015-01-01

Full Text Available Aim: To assess clinical and functional efficacy of implanted biological prosthesis “ASPIRE” (manufactured by Vascutek for correction of mitral valve disease.Materials and methods: From October 2008 to December 2013, biological prostheses “ASPIRE” (Vascutek were implanted to 34 patients with mitral valve disease (mean age 63.59 ± 4.96 years, 79.4% female. From these, 24 patients had mitral stenosis and 10 patients had mitral insufficiency. 73.5% of all patients had heart failure Strazhesko-Vasilenko IIA grade and 85.3% of patients had chronic heart failure NYHA III. Isolated mitral valve replacement was performed only in 8 (23.5% of patients. In 22 (64.7% of cases mitral valve replacement was combined with tricuspid valvuloplasty in various modifications. Duration of cardiopulmonary bypass and of aortic clamping was 88.09 ± 25.95 and 65.68 ± 25.51 minutes, respectively. Before and after surgery all patients underwent echocardiographic assessment and clinical assessment of their general status.Results: In-hospital mortality was 5.88% (n = 2 and was related to multiorgan failure in the early postoperative period. All 32 (94.12% surviving patients improved with decrease or complete disappearance of heart failure. Postoperative complications were typical for cardiac surgery. There were no episodes of embolism, structural dysfunction, thrombosis of the prosthesis and endocarditis of the prosthesis in the early postoperative period. Pressure gradients across prosthetic valves were not high and corresponded to good clinical and hemodynamic results in the early postoperative period.Conclusion: Taking into account good immediate results of mitral valve replacement, as well as no need in lifelong anticoagulation in patients with multiple concomitant disorders, implantation of the biological prosthesis “ASPIRE” (Vascutek could become a procedure of choice for correction of valve abnormalities in patients above 65 years. For more comprehensive

SU-F-T-374: Dosimetric Effects of Irradiation Through a Bilateral Hip Prosthesis in a MRI Linac

Energy Technology Data Exchange (ETDEWEB)

Wronski, M; Sarfehnia, A; Sahgal, A; Keller, B [Sunnybrook Odette Cancer Center, Toronto (Canada); University of Toronto, Department of Radiation Oncology, Toronto (Canada); Ahmad, S [Sunnybrook Odette Cancer Center, Toronto (Canada)

2016-06-15

Purpose: To evaluate the interface effects when irradiating through a hip prosthesis in the presence of an orthogonal 1.5 T magnetic field using Monte Carlo simulations. Methods: A 20×20×38 cm virtual phantom with two 5×5×5 cm sections of bilateral titanium hip prosthesis was created in GPU-based Monte Carlo (MC) algorithm (GPUMCD, Elekta AB, Stockholm Sweden). The lateral prosthesis spacing was based on a representative patient CT scan. A treatment SAD of 143.5 cm was chosen, corresponding to the Elekta AB MRI Linac and the beam energy distribution was sampled from a histogram representing the true MRI Linac spectrum. A magnetic field of 1.5 T was applied perpendicular to the plane of irradiation. Dose was calculated, in voxels of side 1 mm, for 2×2, 5×5, and 10×10 cm treatment field sizes with normal beam incidence (gantry at 90° or 270°) and at 5° and 10° from normal, representing the range of incidence through the bilateral prosthesis. Results: With magnetic field ON (B-On) and normal beam incidence the backscatter dose at the interfaces of proximal and distal implants is reduced for all the field sizes compared to the magnetic field OFF (B-Off) case. The absolute reduction in doses at the interface was in the range of 12.93% to 13.16% for the proximal implant and 13.57% to 16.12% for the distal implant. Similarly for the oblique incidences of 5o and 10o the dose in the plane adjacent to the prosthetic implants is lower when the magnetic field is ON. Conclusion: The dosimetric effects of irradiating through a hip prosthesis in the presence of a transverse magnetic field have been determined using MC simulation. The backscatter dose reduction translates into significantly lower hot spots at the prosthetic interfaces, which are otherwise substantially high in the absence of the magnetic field. This project was supported through funding provided by ElektaTM.

Clinical acceptability of metal-ceramic fixed partial dental prosthesis fabricated with direct metal laser sintering technique-5 year follow-up.

Science.gov (United States)

Prabhu, Radhakrishnan; Prabhu, Geetha; Baskaran, Eswaran; Arumugam, Eswaran M

2016-01-01

In recent years, direct metal laser sintered (DMLS) metal-ceramic-based fixed partial denture prostheses have been used as an alternative to conventional metal-ceramic fixed partial denture prostheses. However, clinical studies for evaluating their long-term clinical survivability and acceptability are limited. The aim of this study was to assess the efficacy of metal-ceramic fixed dental prosthesis fabricated with DMLS technique, and its clinical acceptance on long-term clinical use. The study group consisted of 45 patients who were restored with posterior three-unit fixed partial denture prosthesis made using direct laser sintered metal-ceramic restorations. Patient recall and clinical examination of the restorations were done after 6months and every 12 months thereafter for the period of 60 months. Clinical examination for evaluation of longevity of restorations was done using modified Ryge criteria which included chipping of the veneered ceramic, connector failure occurring in the fixed partial denture prosthesis, discoloration at the marginal areas of the veneered ceramic, and marginal adaptation of the metal and ceramic of the fixed denture prosthesis. Periapical status was assessed using periodical radiographs during the study period. Survival analysis was made using the Kaplan-Meier method. None of the patients had failure of the connector of the fixed partial denture prostheses during the study period. Two exhibited biological changes which included periapical changes and proximal caries adjacent to the abutments. DMLS metal-ceramic fixed partial denture prosthesis had a survival rate of 95.5% and yielded promising results during the 5-year clinical study.

Fabrication of an interim complete removable dental prosthesis with an in-office digital light processing three-dimensional printer: A proof-of-concept technique.

Science.gov (United States)

Lin, Wei-Shao; Harris, Bryan T; Pellerito, John; Morton, Dean

2018-04-30

This report describes a proof of concept for fabricating an interim complete removable dental prosthesis with a digital light processing 3-dimensional (3D) printer. Although an in-office 3D printer can reduce the overall production cost for an interim complete removable dental prosthesis, the process has not been validated with clinical studies. This report provided a preliminary proof of concept in developing a digital workflow for the in-office additively manufactured interim complete removable dental prosthesis. Copyright © 2018 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Breast milk metal ion levels in a young and active patient with a metal-on-metal hip prosthesis.

Science.gov (United States)

Nelis, Raymond; de Waal Malefijt, Jan; Gosens, Taco

2013-01-01

Metal-on-metal resurfacing arthroplasty of the hip has been used increasingly over the last 10 years in younger active patients. The dissolution of the metal wear particles results in measurable increases in cobalt and chromium ions in the serum and urine of patients with a metal-on-metal bearing. We measured the cobalt, chromium, and molybdenum ion levels in urine; serum; and breast milk in a young and active patient with a metal-on-metal hip prosthesis after a pathologic fracture of the femoral neck. Metal-on-metal hip prosthesis leads to increasing levels of molybdenum in breast milk in the short-term follow-up. There are no increasing levels of chromium and cobalt ions in breast milk. Besides the already known elevated concentrations in serum of chromium and cobalt after implantation of a metal-on-metal hip prosthesis, we found no increasing levels of chromium and cobalt in urine. Copyright © 2013 Elsevier Inc. All rights reserved.

Meniscal replacement using a porous polymer prosthesis : A preliminary study in the dog

NARCIS (Netherlands)

Veth, RPH; Jansen, HWB; Nielsen, HKL; deGroot, JH; Pennings, AJ

A porous polyurethane prosthesis was used to replace the lateral meniscus in the dog. After an initial ingrowth of fibrous tissue, the prostheses became filled with tissue strongly resembling normal meniscal fibrocartilage. Although less severe than seen after total meniscectomy, cartilage

21 CFR 888.3510 - Knee joint femorotibial metal/polymer constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/polymer constrained... Knee joint femorotibial metal/polymer constrained cemented prosthesis. (a) Identification. A knee joint... of a knee joint. The device limits translation or rotation in one or more planes and has components...

21 CFR 888.3100 - Ankle joint metal/composite semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ankle joint metal/composite semi-constrained... Ankle joint metal/composite semi-constrained cemented prosthesis. (a) Identification. An ankle joint... ankle joint. The device limits translation and rotation: in one or more planes via the geometry of its...

Clinical Implantation with the novel D-13 prosthesis for inguinal hernioplasty: A retrospective cohort study.

Science.gov (United States)

Gao, Peng-Zhi; Li, Ming; Yu, Ying-Jian; Hao, Xiang-Dong; Li, Wu-Zi; Rong, Ya-Jun; Zheng, Zhi-Gang; Meng, Ning

2015-05-01

Using a mesh to repair inguinal hernias is now a standard procedure that is widely accepted as superior to primary suture repair. Although a variety of meshes are available, individual meshes may have their own unattractive features. This retrospective study examines the efficacy of our originally designed D-13 prosthesis, which is used in patients with inguinal hernias. A total of 305 patients who underwent a herniorrhaphy between January 2009 and March 2011 were included in this study. The recurrent rate, chronic pain and feeling of a foreign body were examined at a 3-year follow-up. The D-13 prosthesis, made from clear polypropylene monofilament mesh, was originally designed by the first author of this study and constructed with the upper and lower pieces of polypropylene mesh having different shapes and sizes. Both pieces are linked together by a connector. The mesh is well tolerated. At a 3-year follow-up, only two patients had a foreign body sensation at the operative site, and three patients had recurrent hernias. The unique design of the D-13 prosthesis with two pieces of mesh provided encouraging long-term outcome for hernia recurrence, chronic pain and the feeling of a foreign body. Copyright © 2015 IJS Publishing Group Limited. All rights reserved.

Precision assessment of model-based RSA for a total knee prosthesis in a biplanar set-up.

Science.gov (United States)

Trozzi, C; Kaptein, B L; Garling, E H; Shelyakova, T; Russo, A; Bragonzoni, L; Martelli, S

2008-10-01

Model-based Roentgen Stereophotogrammetric Analysis (RSA) was recently developed for the measurement of prosthesis micromotion. Its main advantage is that markers do not need to be attached to the implants as traditional marker-based RSA requires. Model-based RSA has only been tested in uniplanar radiographic set-ups. A biplanar set-up would theoretically facilitate the pose estimation algorithm, since radiographic projections would show more different shape features of the implants than in uniplanar images. We tested the precision of model-based RSA and compared it with that of the traditional marker-based method in a biplanar set-up. Micromotions of both tibial and femoral components were measured with both the techniques from double examinations of patients participating in a clinical study. The results showed that in the biplanar set-up model-based RSA presents a homogeneous distribution of precision for all the translation directions, but an inhomogeneous error for rotations, especially internal-external rotation presented higher errors than rotations about the transverse and sagittal axes. Model-based RSA was less precise than the marker-based method, although the differences were not significant for the translations and rotations of the tibial component, with the exception of the internal-external rotations. For both prosthesis components the precisions of model-based RSA were below 0.2 mm for all the translations, and below 0.3 degrees for rotations about transverse and sagittal axes. These values are still acceptable for clinical studies aimed at evaluating total knee prosthesis micromotion. In a biplanar set-up model-based RSA is a valid alternative to traditional marker-based RSA where marking of the prosthesis is an enormous disadvantage.

Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis.

Science.gov (United States)

Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario

2015-12-01

Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.

Percutaneous implantation of the first repositionable aortic valve prosthesis in a patient with severe aortic stenosis.

Science.gov (United States)

Buellesfeld, Lutz; Gerckens, Ulrich; Grube, Eberhard

2008-04-01

Percutaneous aortic valve replacement is a new less-invasive alternative for high-risk surgical candidates with aortic stenosis. However, the clinical experience is still limited, and the currently available 'first-generation devices' revealed technical shortcomings, such as lack of repositionability and presence of paravalvular leakages. We report the first-in-man experience with the new self-expanding Lotus Valve prosthesis composed of a nitinol frame with implemented bovine pericardial leaflets which is designed to address these issues, being repositionable and covered by a flexible membrane to seal paravalvular gaps. We implanted this prosthesis in a 93-year old patient presenting with severe symptomatic aortic stenosis (valve area: 0.6 cm(2)). Surgical valve replacement had been declined due to comorbidities. We used a retrograde approach for insertion of the 21-French Lotus catheter loaded with the valve prosthesis via surgical cut-down to the external iliac artery. Positioning of the valve was guided by transesophageal echo and supra-aortic angiograms. The prosthesis was successfully inserted and deployed within the calcified native valve. Echocardiography immediately after device deployment showed a significant reduction of the transaortic mean pressure gradient (32 to 9 mmHg; final valve area 1.7 cm(2)) without evidence of residual aortic regurgitation. The postprocedural clinical status improved from NYHA-IV to NYHA-II. These results remained unchanged up to the 3 month follow-up. Successful percutaneous aortic valve replacement can be performed using the new self-expanding and repositionable Lotus valve for treatment of high-risk patients with aortic valve stenosis. Further studies are mandatory to assess device safety and efficacy in larger patient populations. Copyright 2008 Wiley-Liss, Inc.

Good quality of life outcomes after treatment of prosthetic joint infection with debridement and prosthesis retention.

Science.gov (United States)

Aboltins, Craig; Dowsey, Michelle; Peel, Trish; Lim, Wen K; Choong, Peter

2016-05-01

Patients treated for early prosthetic joint infection (PJI) with surgical debridement and prosthesis retention have a rate of successful infection eradication that is similar to patients treated with the traditional approach of prosthesis exchange. It is therefore important to consider other outcomes after prosthetic joint infection treatment that may influence management decisions, such as quality of life (QOL). Our aim was to describe infection cure rates and quality of life for patients with prosthetic joint infection treated with debridement and prosthesis retention and to determine if treatment with this approach was a risk factor for poor quality of life outcomes. Prospectively collected pre and post-arthroplasty data were available for 2,134 patients, of which PJI occurred in 41. For patients treated for prosthetic joint infection, the 2-year survival free of treatment failure was 87% (95%CI 84-89). Prosthetic joint infection cases treated with debridement and retention had a similar improvement from pre-arthroplasty to 12-months post-arthroplasty as patients without PJI in QOL according to the SF-12 survey. Prosthetic joint infection treated with debridement and retention was not a risk factor for poor quality of life on univariate or multivariate analysis. Prosthetic joint infection treated with debridement and prosthesis retention results in good cure rates and quality of life. Further studies are required that directly compare quality of life for different surgical approaches for prosthetic joint infection to better inform management decisions. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:898-902, 2016. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

INSIST-ED: Italian Society of Andrology registry on penile prosthesis surgery. First data analysis

Directory of Open Access Journals (Sweden)

Edoardo Pescatori

2016-07-01

Full Text Available Objectives: The Italian Society of Andrology, i.e. “Società Italiana di Andrologia” (S.I.A., launched on December 2014 a prospective, multicenter, monitored and internal review board approved Registry for penile implants, the “INSIST-ED” (Italian Nationwide Systematic Inventarisation of Surgical Treatment for ED Registry. Purpose of this first report is to present a baseline data analysis of the characteristics of penile implant surgery in Italy. Material and methods: The INSIST-ED Registry is open to all surgeons implanting penile prostheses (all brands, all models in Italy, providing anonymous patient, device, surgical procedure, outcome, follow-up data, for both first and revision surgeries. A Registry project Board overviews all the steps of the project, and a Registry Monitor interacts with the Registry implanting surgeons. Results: As by April 8, 2016, 31 implanting surgeons actively joined the Registry, entering 367 surgical procedures in its database, that comprise: 310 first implants, 43 prosthesis substitutions, 14 device explants without substitution. Implanted devices account for: 288 three-component devices (81,3%, 20 two-component devices (5,4%, 45 non-hydraulic devices (12,3%. Leading primary ED etiologies in first implant surgeries resulted: former radical pelvic surgery in 111 cases (35,8%, Peyronie’s disease in 66 cases (21,3%, diabetes in 39 cases (12,6%. Two intraoperative complications have been recorded. Main reasons for 57 revision surgeries were: device failure (52,6%, erosion (19,3%, infection (12,3%, patient dissatisfaction (10,5%. Surgical settings for patients undergoing a first penile implant were: public hospitals in 251 cases (81%, private environments in 59 cases (19%. Conclusions: The INSIST-ED Registry represents the first European experience of penile prosthesis Registry. This baseline data analysis shows that: three-pieces inflatable prosthesis is the most implanted device, leading etiology of