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Sample records for metatarsal stress fractures

  1. Metatarsal stress fractures - aftercare

    Science.gov (United States)

    ... Metatarsal stress fracture. In: Safran MR, Zachazewski J, Stone DA, eds. Instructions for Sports Medicine Patients . 2nd ed. Elsevier Saunders; 2012:648-652. Smith MS. Metatarsal fractures. In: Eiff PM, Hatch R, eds. Fracture Management for Primary Care . 3rd ed. ...

  2. Epidemiology of metatarsal stress fractures versus tibial and femoral stress fractures during elite training.

    Science.gov (United States)

    Finestone, Aharon; Milgrom, Charles; Wolf, Omer; Petrov, Kaloyan; Evans, Rachel; Moran, Daniel

    2011-01-01

    The training of elite infantry recruits takes a year or more. Stress fractures are known to be endemic in their basic training and the clinical presentation of tibial, femoral, and metatarsal stress fractures are different. Stress fracture incidence during the subsequent progressively more demanding training is not known. The study hypothesis was that after an adaptation period, the incidence of stress fractures during the course of 1 year of elite infantry training would fall in spite of the increasingly demanding training. Seventy-six male elite infantry recruits were followed for the development of stress fractures during a progressively more difficult training program composed of basic training (1 to 14 weeks), advanced training (14 to 26 weeks), and unit training (26 to 52 weeks). Subjects were reviewed regularly and those with clinical suspicion of stress fracture were assessed using bone scan and X-rays. The incidence of stress fractures was 20% during basic training, 14% during advanced training and 23% during unit training. There was a statistically significant difference in the incidence of tibial and femoral stress fractures versus metatarsal stress fractures before and after the completion of phase II training at week 26 (p=0.0001). Seventy-eight percent of the stress fractures during phases I and II training were either tibial or femoral, while 91% of the stress fractures in phase III training were metatarsal. Prior participation in ball sports (p=0.02) and greater tibial length (p=0.05) were protective factors for stress fracture. The study hypothesis that after a period of soldier adaptation, the incidence of stress fractures would decrease in spite of the increasingly demanding elite infantry training was found to be true for tibial and femoral fractures after 6 months of training but not for metatarsal stress fractures. Further studies are required to understand the mechanism of this difference but physicians and others treating stress fractures

  3. Factors associated with recurrent fifth metatarsal stress fracture.

    Science.gov (United States)

    Lee, Kyung-tai; Park, Young-uk; Jegal, Hyuk; Kim, Ki-chun; Young, Ki-won; Kim, Jin-su

    2013-12-01

    Many surgeons agree that fifth metatarsal stress fractures have a tendency toward delayed union, nonunion, and possibly refracture. Difficulty healing seems to be correlated with fracture classification. However, refracture sometimes occurs after low-grade fracture, even long after apparent resolution. The records of 168 consecutive cases of fifth metatarsal stress fracture (163 patients) treated by modified tension band wiring from March 2002 to June 2011 were evaluated retrospectively. Mean length of follow-up was 23.6 months (range, 10-112 months). Forty-nine cases classified as Torg III were bone grafted initially also. All enrolled patients were elite athletes. Eleven patients experienced nonunion and 18 refracture. The 11 nonunion cases were bone grafted. The 157 patients (excluding nonunion cases) were allocated to either a refracture group or a union group. Clinical features, such as age, weight, fracture classification, time to union, and reinjury history, were compared. Radiological parameters representing cavus deformity and fifth metatarsal head protrusion were compared to evaluate the influence of structural abnormalities. Mean group weights were significantly different (P = .041), but mean ages (P = .879), fracture grades (P = .216, P = .962), and time from surgery to rehabilitation (P = .539) were similar. No significant intergroup differences were found for talocalcaneal (TC) angle (P = .470), calcaneal pitch (CP) angle (P = .847), or talo-first metatarsal (T-MT1) angle (P = .407) on lateral radiographs; for fifth metatarsal lateral deviation (MT5-LD) angle (P = .623) on anteroposterior (AP) radiographs; or for MT5-LD angle (P = .065) on the 30-degree medial oblique radiographs. However, the mean fourth-fifth intermetatarsal (IMA4-5) angle on AP radiographs was significantly greater in the refracture group, and for Torg II cases, mean weight (P = .042), IMA4-5 angle on AP radiographs (P = .014), and MT5-LD angle (P = .043) on 30-degree medial

  4. 99mTc-MDP bone scintigraphy in the diagnosis of stress fracture of the metatarsal bones mimicking oligoarthritis

    Directory of Open Access Journals (Sweden)

    Jauković Ljiljana

    2008-01-01

    Full Text Available Background. Stress fractures are the injuries of soft tissues and bones caused by intensive and repeated stress on a bone. Repeated submaximal stress disturbs the balance between the processes of bone production and resorption that results in fracture. Case report. We presented a case of a patient with stress fracture of metatarsal bone. The patient was diagnosed and treated as having reactive oligoarthritis caused by Chlamydia trachomatis and administered antibiotics. Initial plain radiography was negative for bone fracture. Tc-99m bone scintigraphy suggested stress fracture of the second metatarsal. Plain radiography was became positive three weeks later, showing callus formation in the proximal part of the second metatarsal. Conclusion. Bone scintigraphy is a diagnostic test of choice in early diagnosis of stress fracture, and it is important to apply it timely in order to include the entire therapy and prevent complications, as well as to let a patient return to previous daily activites.

  5. Stress fractures of the base of the metatarsal bones in young trainee ballet dancers

    Science.gov (United States)

    Albisetti, Walter; De Bartolomeo, Omar; Tagliabue, Lorenzo; Camerucci, Emanuela; Calori, Giorgio Maria

    2009-01-01

    Classical ballet is an art form requiring extraordinary physical activity, characterised by rigorous training. These can lead to many overuse injuries arising from repetitive minor trauma. The purpose of this paper is to report our experience in the diagnosis and treatment of stress fractures at the base of the second and third metatarsal bones in young ballet dancers. We considered 150 trainee ballet dancers from the Ballet Schools of "Teatro Alla Scala" of Milan from 2005 to 2007. Nineteen of them presented with stress fractures of the base of the metatarsal bones. We treated 18 dancers with external shockwave therapy (ESWT) and one with pulsed electromagnetic fields (EMF) and low-intensity ultrasound (US); all patients were recommended rest. In all cases good results were obtained. The best approach to metatarsal stress fractures is to diagnose them early through clinical examination and then through X-ray and MRI. ESWT gave good results, with a relatively short time of rest from the patients’ activities and a return to dancing without pain. PMID:19415273

  6. Demographics and outcome of metatarsal fractures

    NARCIS (Netherlands)

    Cakir, H.; van Vliet-Koppert, S. T.; van Lieshout, E. M. M.; de Vries, M. R.; van der Elst, M.; Schepers, T.

    2011-01-01

    Although metatarsal fractures are amongst the most common injuries of the foot, this is the first study on outcome after metatarsal fractures. All consecutive patients with metatarsal fractures treated between January 2006 and September 2008 were re-evaluated. Patients aged 16 to 75 were sent a

  7. Characteristics of the Foot Static Alignment and the Plantar Pressure Associated with Fifth Metatarsal Stress Fracture History in Male Soccer Players: a Case-Control Study.

    Science.gov (United States)

    Matsuda, Sho; Fukubayashi, Toru; Hirose, Norikazu

    2017-12-01

    There is a large amount of information regarding risk factors for fifth metatarsal stress fractures; however, there are few studies involving large numbers of subjects. This study aimed to compare the static foot alignment and distribution of foot pressure of athletes with and without a history of fifth metatarsal stress fractures. The study participants comprised 335 collegiate male soccer players. Twenty-nine with a history of fifth metatarsal stress fractures were in the fracture group and 306 were in the control group (with subgroups as follows: 30 in the fracture foot group and 28 in the non-fracture group). We measured the foot length, arch height, weight-bearing leg-heel alignment, non-weight-bearing leg-heel alignment, forefoot angle relative to the rearfoot, forefoot angle relative to the horizontal axis, and foot pressure. The non-weight-bearing leg-heel alignment was significantly smaller and the forefoot angle relative to the rearfoot was significantly greater in the fracture foot group than in the control foot group (P = 0.049 and P = 0.038, respectively). With regard to plantar pressure, there were no significant differences among the groups. Midfield players had significantly higher rates of fifth metatarsal stress fracture in their histories, whereas defenders had significantly lower rates (chi-square = 13.2, P stress fractures according to the type of foot (kicking foot vs. pivoting foot) or the severity of ankle sprain. Playing the midfield position and having an everted rearfoot and inverted forefoot alignment were associated with fifth metatarsal stress fractures. This information may be helpful for preventing fifth metatarsal stress fracture recurrence. More detailed load evaluations and a prospective study are needed in the future.

  8. The effect of concentrated bone marrow aspirate in operative treatment of fifth metatarsal stress fractures; a double-blind randomized controlled trial

    NARCIS (Netherlands)

    Weel, Hanneke; Mallee, Wouter H.; van Dijk, C. Niek; Blankevoort, Leendert; Goedegebuure, Simon; Goslings, J. Carel; Kennedy, John G.; Kerkhoffs, Gino M. M. J.

    2015-01-01

    Fifth metatarsal (MT-V) stress fractures often exhibit delayed union and are high-risk fractures for non-union. Surgical treatment, currently considered as the gold standard, does not give optimal results, with a mean time to fracture union of 12-18 weeks. In recent studies, the use of bone marrow

  9. Barefoot-simulating footwear associated with metatarsal stress injury in 2 runners.

    Science.gov (United States)

    Giuliani, Jeffrey; Masini, Brendan; Alitz, Curtis; Owens, Brett D

    2011-07-07

    Stress-related changes and fractures in the foot are frequent in runners. However, the causative factors, including anatomic and kinematic variables, are not well defined. Footwear choice has also been implicated in contributing to injury patterns with changes in force transmission and gait analyses reported in the biomechanical literature. Despite the benefits of footwear, there has been increased interest among the running community in barefoot running with proposed benefits including a decreased rate of injury. We report 2 cases of metatarsal stress fracture in experienced runners whose only regimen change was the adoption of barefoot-simulating footwear. One was a 19-year-old runner who developed a second metatarsal stress reaction along the entire diaphysis. The second case was a 35-year-old ultra-marathon runner who developed a fracture in the second metatarsal diaphysis after 6 weeks of use of the same footwear. While both stress injuries healed without long-term effects, these injuries are alarming in that they occurred in experienced male runners without any other risk factors for stress injury to bone. The suspected cause for stress injury in these 2 patients is the change to barefoot-simulating footwear. Runners using these shoes should be cautioned on the potential need for gait alterations from a heel-strike to a midfoot-striking pattern, as well as cautioned on the symptoms of stress injury. Copyright 2011, SLACK Incorporated.

  10. Metatarsal fracture (acute) - aftercare

    Science.gov (United States)

    ... of your 5th metatarsal bone closest to the ankle is called a Jones fracture. This area of the bone has low blood ... Swelling, pain, numbness, or tingling in your leg, ankle, or foot that becomes worse Your leg or foot turns purple Fever

  11. An unusual stress fracture: Bilateral posterior longitudinal stress fracture of tibia

    OpenAIRE

    Malkoc, Melih; Korkmaz, Ozgur; Ormeci, Tugrul; Oltulu, Ismail; Isyar, Mehmet; Mahirogulları, Mahir

    2014-01-01

    INTRODUCTION Stress fractures (SF) occur when healthy bone is subjected to cyclic loading, which the normal carrying range capacity is exceeded. Usually, stress fractures occur at the metatarsal bones, calcaneus, proximal or distal tibia and tends to be unilateral. PRESENTATION OF CASE This article presents a 58-year-old male patient with bilateral posterior longitudinal tibial stress fractures. A 58 years old male suffering for persistent left calf pain and decreased walking distance for las...

  12. Clinical evaluation of stress fractures using bone scintigraphy

    International Nuclear Information System (INIS)

    Furuta, Atsuhiko; Tanohata, Kazunori; Otake, Toru; Hashizume, Toshiyuki; Kobayashi, Yozi; Nakazima, Hiroyuki.

    1984-01-01

    Clinical evaluation of stress fractures were performed in 58 athletes using bone scintigraphy with sup(99m)Tc-MDP. Stress fractures of the tibia were most often seen in the males with running type sports. They occurred more often in the proximal tibia and on the right side. Stress fractures of the fibula were most often seen in females with jumping type sports, such as volley ball. They occurred more often in the distal fibula and on the right side. Tarsal bone fractures were seen most often rugby players. Metatarsal fractures occurred in the third fourth and fifth metatarsals. No lesion was seen in the first and second metatarsals. We feel that stress fractures of the femur can be differentiated from osteosarcoma by small loculated radionuclide accumulation as well as symptome, course and tomographic and CT finding. Bilateral involvement was seen in two cases in patellae and calcanei. Most of the other fractures were seen on the right side. Negative radiographs were seen in 36% of the patients and occurred most commonly in the tarsal bones excluding calcaneus. Bone scintigrams were positive in all cases and were most useful in fractures of the tarsal bones excluding calcaneus. (author)

  13. Clinical evaluation of stress fractures using bone scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Atsuhiko; Tanohata, Kazunori; Otake, Toru; Hashizume, Toshiyuki (Kanto Rosai Hospital, Kawasaki, Kanagawa (Japan)); Kobayashi, Yozi; Nakazima, Hiroyuki

    1984-05-01

    Clinical evaluation of stress fractures were performed in 58 athletes using bone scintigraphy with sup(99m)Tc-MDP. Stress fractures of the tibia were most often seen in the males with running type sports. They occurred more often in the proximal tibia and on the right side. Stress fractures of the fibula were most often seen in females with jumping type sports, such as volley ball. They occurred more often in the distal fibula and on the right side. Tarsal bone fractures were seen most often rugby players. Metatarsal fractures occurred in the third fourth and fifth metatarsals. No lesion was seen in the first and second metatarsals. We feel that stress fractures of the femur can be differentiated from osteosarcoma by small loculated radionuclide accumulation as well as symptoms, course and tomographic and CT findings. Bilateral involvement was seen in two cases in patellae and calcanei. Most of the other fractures were seen on the right side. Negative radiographs were seen in 36% of the patients and occurred most commonly in the tarsal bones excluding calcaneus. Bone scintigrams were positive in all cases and were most useful in fractures of the tarsal bones excluding calcaneus.

  14. Atypical stress-avulsion fracture of the Lisfranc joint complex.

    LENUS (Irish Health Repository)

    O'Neill, Barry J

    2014-04-01

    Antiphospholipid syndrome and systemic erythematosus have been associated with metatarsal stress fractures. Stress fractures of the Lisfranc joint complex are uncommon injuries but have been reported to occur most frequently in ballet dancers. We present a case of an avulsion fracture of the Lisfranc joint complex that occurred spontaneously. We have reviewed the association between systemic conditions and metatarsal fractures and proposed a series of hypothetical pathological events that may have contributed to this unusual injury.

  15. Atypical metatarsal fracture in a patient on long term bisphosphonate therapy

    Directory of Open Access Journals (Sweden)

    Pavan Pradhan

    2012-01-01

    Full Text Available A 24 years old female of cushing disease had undergone adrenelectomy. She was put on alendronate and steroid. After six and a half years she developed pathological fracture subtrochanteric femur. The patient was treated with proximal femoral nailing and the fracture united. 2 years later she developed pain right foot. She was diagnosed as transverse fracture of fifth metatarsal. We report this rare case of atypical metatarsal fracture in a patient on long term bisphosphonate therapy.

  16. Surgical versus conservative treatment for high-risk stress fractures of the lower leg (anterior tibial cortex, navicular and fifth metatarsal base): a systematic review

    NARCIS (Netherlands)

    Mallee, Wouter H.; Weel, Hanneke; van Dijk, C. Niek; van Tulder, Maurits W.; Kerkhoffs, Gino M.; Lin, Chung-Wei Christine

    2015-01-01

    To compare surgical and conservative treatment for high-risk stress fractures of the anterior tibial cortex, navicular and proximal fifth metatarsal. Systematic searches of CENTRAL, MEDLINE, EMBASE, CINAHL, SPORTDiscus and PEDro were performed to identify relevant prospective and retrospective

  17. Surgical versus conservative treatment for high-risk stress fractures of the lower leg (anterior tibial cortex, navicular and fifth metatarsal base): a systematic review

    NARCIS (Netherlands)

    Mallee, W.H.; Weel, H.; van Dijk, C.N.; van Tulder, M.W.; Kerkhoffs, G.M.; Lin, C.W.C.

    2015-01-01

    Aim To compare surgical and conservative treatment for high-risk stress fractures of the anterior tibial cortex, navicular and proximal fifth metatarsal. Methods Systematic searches of CENTRAL, MEDLINE, EMBASE, CINAHL, SPORTDiscus and PEDro were performed to identify relevant prospective and

  18. Operative Treatment of Fifth Metatarsal Jones Fractures (Zones II and III) in the NBA.

    Science.gov (United States)

    O'Malley, Martin; DeSandis, Bridget; Allen, Answorth; Levitsky, Matthew; O'Malley, Quinn; Williams, Riley

    2016-05-01

    Proximal fractures of the fifth metatarsal (zone II and III) are common in the elite athlete and can be difficult to treat because of a tendency toward delayed union, nonunion, or refracture. The purpose of this case series was to report our experience in treating 10 NBA players, determine the healing rate, return to play, refracture rate, and role of foot type in these athletes. The records of 10 professional basketball players were retrospectively reviewed. Seven athletes underwent standard percutaneous internal fixation with bone marrow aspirate concentrate (BMAC) whereas the other 3 had open bone grafting primarily in addition to fixation and BMAC. Radiographic features evaluated included fourth-fifth intermetatarsal, fifth metatarsal lateral deviation, calcaneal pitch, and metatarsus adductus angles. Radiographic healing was observed at an overall average of 7.5 weeks and return to play was 9.8 weeks. Three athletes experienced refractures. There were no significant differences in clinical features or radiographic measurements except that the refracture group had the highest metatatarsus adductus angles. Most athletes were pes planus and 9 of 10 had a bony prominence under the fifth metatarsal styloid. This is the largest published series of operatively treated professional basketball players who exemplify a specific patient population at high risk for fifth metatarsal fracture. These players were large and possessed a unique foot type that seemed to be associated with increased risk of fifth metatarsal fracture and refracture. This foot type had forefoot metatarsus adductus and a fifth metatarsal that was curved with a prominent base. We continue to use standard internal fixation with bone marrow aspirate but advocate additional prophylactic open bone grafting in patients with high fourth-to-fifth intermetatarsal, fifth metatarsal lateral deviation, and metatarsus adductus angles as well as prominent fifth metatarsal styloids in order to improve fracture

  19. Effects of footwear and stride length on metatarsal strains and failure in running.

    Science.gov (United States)

    Firminger, Colin R; Fung, Anita; Loundagin, Lindsay L; Edwards, W Brent

    2017-11-01

    The metatarsal bones of the foot are particularly susceptible to stress fracture owing to the high strains they experience during the stance phase of running. Shoe cushioning and stride length reduction represent two potential interventions to decrease metatarsal strain and thus stress fracture risk. Fourteen male recreational runners ran overground at a 5-km pace while motion capture and plantar pressure data were collected during four experimental conditions: traditional shoe at preferred and 90% preferred stride length, and minimalist shoe at preferred and 90% preferred stride length. Combined musculoskeletal - finite element modeling based on motion analysis and computed tomography data were used to quantify metatarsal strains and the probability of failure was determined using stress-life predictions. No significant interactions between footwear and stride length were observed. Running in minimalist shoes increased strains for all metatarsals by 28.7% (SD 6.4%; pRunning at 90% preferred stride length decreased strains for metatarsal 4 by 4.2% (SD 2.0%; p≤0.007), and no differences in probability of failure were observed. Significant increases in metatarsal strains and the probability of failure were observed for recreational runners acutely transitioning to minimalist shoes. Running with a 10% reduction in stride length did not appear to be a beneficial technique for reducing the risk of metatarsal stress fracture, however the increased number of loading cycles for a given distance was not detrimental either. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. An unusual stress fracture: Bilateral posterior longitudinal stress fracture of tibia.

    Science.gov (United States)

    Malkoc, Melih; Korkmaz, Ozgur; Ormeci, Tugrul; Oltulu, Ismail; Isyar, Mehmet; Mahirogulları, Mahir

    2014-01-01

    Stress fractures (SF) occur when healthy bone is subjected to cyclic loading, which the normal carrying range capacity is exceeded. Usually, stress fractures occur at the metatarsal bones, calcaneus, proximal or distal tibia and tends to be unilateral. This article presents a 58-year-old male patient with bilateral posterior longitudinal tibial stress fractures. A 58 years old male suffering for persistent left calf pain and decreased walking distance for last one month and after imaging studies posterior longitudinal tibial stress fracture was detected on his left tibia. After six months the patient was admitted to our clinic with the same type of complaints in his right leg. All imaging modalities and blood counts were performed and as a result longitudinal posterior tibial stress fractures were detected on his right tibia. Treatment of tibial stress fracture includes rest and modified activity, followed by a graded return to activity commensurate with bony healing. We have applied the same treatment protocol and our results were acceptable but our follow up time short for this reason our study is restricted for separate stress fractures of the posterior tibia. Although the main localization of tibial stress fractures were unilateral, anterior and transverse pattern, rarely, like in our case, the unusual bilateral posterior localization and longitudinal pattern can be seen. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Plate Fixation With Autogenous Calcaneal Dowel Grafting Proximal Fourth and Fifth Metatarsal Fractures: Technique and Case Series.

    Science.gov (United States)

    Seidenstricker, Chad L; Blahous, Edward G; Bouché, Richard T; Saxena, Amol

    Metaphyseal and proximal diaphyseal fractures of the lateral column metatarsals can have problems with healing. In particular, those involving the fifth metatarsal have been associated with a high nonunion rate with nonoperative treatment. Although intramedullary screw fixation results in a high union rate, delayed healing and complications can occur. We describe an innovative technique to treat both acute and chronic injuries involving the metatarsal base from the metaphysis to the proximal diaphyseal bone of the fourth and fifth metatarsals. The surgical technique involves evacuation of sclerotic bone at the fracture site, packing the fracture site with compact cancellous bone, and plate fixation. In our preliminary results, 4 patients displayed 100% radiographic union at a mean of 4.75 (range 4 to 6) weeks with no incidence of refracture, at a mean follow-up point of 3.5 (range 1 to 5) years. The early results with our small series suggest that this technique is a useful treatment choice for metaphyseal and proximal diaphyseal fractures of the fourth and fifth metatarsals. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Extracorporeal shock wave treatment of non- or delayed union of proximal metatarsal fractures.

    Science.gov (United States)

    Alvarez, Richard G; Cincere, Brandon; Channappa, Chandra; Langerman, Richard; Schulte, Robert; Jaakkola, Juha; Melancon, Keith; Shereff, Michael; Cross, G Lee

    2011-08-01

    Nonunion or delayed union of fractures in the proximal aspect of metatarsals 1 to 4 and Zone 2 of the fifth metatarsal were treated by high energy extracorporeal shock wave treatment (ESWT) to study the safety and efficacy of this method of treatment in a FDA study of the Ossatron device. In a prospective single-arm, multi-center study, 34 fractures were treated in 32 patients (two subjects had two independent fractures) with ESWT. All fractures were at least 10 (range, 10 to 833) weeks after injury, with a median of 23 weeks. ESWT application was conducted using a protocol totaling 2,000 shocks for a total energy application of approximately 0.22 to 0.51 mJ/mm2 per treatment. The mean ESWT application time for each of the treatments was 24.6 +/- 16.6 minutes, and anesthesia time averaged 27.1 +/- 10.4 minutes. All subjects were followed for 1 year after treatment at intervals of 12 weeks, 6, 9, and 12 months. The overall success rate at the 12-week visit was 71% with low complications, significant pain improvement as well as improvement on the SF-36. The success/fail criteria was evaluated again at the 6- and 12-month followup, showing treatment success rates of 89% (23/26) and 90% (18/20), respectively. The most common adverse event was swelling in the foot, reported by five subjects (15.6%). High-energy ESWT appears to be effective and safe in patients for treatment of nonunion or a delayed healing of a proximal metatarsal, and in fifth metatarsal fractures in Zone 2.

  3. Fifth metatarsal fractures among male professional footballers: a potential career-ending disease

    NARCIS (Netherlands)

    Ekstrand, Jan; van Dijk, C. Niek

    2013-01-01

    There is little information about Metatarsal Five (MT-5) fractures for specific sports. To study the occurrence, the imaging characteristics, the lay-off times and healing problems of MT-5 fractures among male footballers. Sixty-four European elite teams were monitored from 2001 to 2012. x-Rays were

  4. Suture Anchor Fixation for Fifth Metatarsal Tuberosity Avulsion Fractures: A Case Series and Review of Literature.

    Science.gov (United States)

    Hong, Choon Chiet; Nag, Kushal; Yeow, Huifen; Lin, Adrian Zhigao; Tan, Ken Jin

    2018-05-17

    Fifth metatarsal tuberosity avulsion fractures are common. Despite good outcomes with nonoperative treatment, acute fractures with displacement, intra-articular involvement, comminution, or painful nonunion have been reported to benefit from early open reduction and internal fixation, especially in athletes. No consensus has been reached regarding the best surgical fixation technique. We present a case series of 4 patients with displaced fifth metatarsal tuberosity avulsion fractures and an innovative technique of fixation for the tuberosity avulsion fractures using a suture anchor. Copyright © 2018 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Stress fractures in athletes

    International Nuclear Information System (INIS)

    Steingruber, I.E.; Wolf, C.; Gruber, H.; Czermak, B.V.; Mallouhi, A.; Jaschke, W.; Gabriel, M.

    2002-01-01

    Stress fractures may pose a diagnostic dilemma for radiologists since they are sometimes difficult to demonstrate on plain films and may simulate a tumour. They were first described in military personnel and professional athletes. Recently, there is an increasing incidence in the general population due to increasing sportive activities. Stress fractures occur most often in the lower extremities, especially in the tibia, the tarsal bone, the metatarsal bone, the femur and the fibula. In the upper extremities, they are commonly found in the humerus, the radius and the ulna. Some fractures of the lower extremities appear to be specific for particular sports, for example, fractures of the tibia affect mostly distance runners. Whereas stress fractures of the upper extremities are generally associated with upper limb-dominated sports. A correct diagnosis requires a careful clinical evaluation. The initial plain radiography may be normal. Further radiological evaluation could be performed by means of computerised tomography, magnetic resonance imaging and bone scanning. The latter two techniques are especially helpful for establishing a correct initial diagnosis. (orig.) [de

  6. Stress fractures of the foot and ankle.

    Science.gov (United States)

    Welck, M J; Hayes, T; Pastides, P; Khan, W; Rudge, B

    2017-08-01

    Stress fractures occur as a result of microscopic injuries sustained when bone is subjected to repeated submaximal stresses. Overtime, with repeated cycles of loading, accumulation of such injuries can lead to macro-structural failure and frank fracture. There are numerous stress fractures about the foot and ankle of which a trauma and orthopaedic surgeon should be aware. These include: metatarsal, tibia, calcaneus, navicular, fibula, talus, medial malleolus, sesamoid, cuneiform and cuboid. Awareness of these fractures is important as the diagnosis is frequently missed and appropriate treatment delayed. Late identification can be associated with protracted pain and disability, and may predispose to non-union and therefore necessitate operative intervention. This article outlines the epidemiology and risk factors, aetiology, presentation and management of the range of stress fractures in the foot and ankle. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Stress fractures of the foot and ankle, part 2: site-specific etiology, imaging, and treatment, and differential diagnosis.

    Science.gov (United States)

    Mandell, Jacob C; Khurana, Bharti; Smith, Stacy E

    2017-09-01

    Stress fractures of the foot and ankle are a commonly encountered problem among athletes and individuals participating in a wide range of activities. This illustrated review, the second of two parts, discusses site-specific etiological factors, imaging appearances, treatment options, and differential considerations of stress fractures of the foot and ankle. The imaging and clinical management of stress fractures of the foot and ankle are highly dependent on the specific location of the fracture, mechanical forces acting upon the injured site, vascular supply of the injured bone, and the proportion of trabecular to cortical bone at the site of injury. The most common stress fractures of the foot and ankle are low risk and include the posteromedial tibia, the calcaneus, and the second and third metatarsals. The distal fibula is a less common location, and stress fractures of the cuboid and cuneiforms are very rare, but are also considered low risk. In contrast, high-risk stress fractures are more prone to delayed union or nonunion and include the anterior tibial cortex, medial malleolus, navicular, base of the second metatarsal, proximal fifth metatarsal, hallux sesamoids, and the talus. Of these high-risk types, stress fractures of the anterior tibial cortex, the navicular, and the proximal tibial cortex may be predisposed to poor healing because of the watershed blood supply in these locations. The radiographic differential diagnosis of stress fracture includes osteoid osteoma, malignancy, and chronic osteomyelitis.

  8. Lower limb stress fractures in sport: Optimising their management and outcome

    Science.gov (United States)

    Robertson, Greg A J; Wood, Alexander M

    2017-01-01

    Stress fractures in sport are becoming increasing more common, comprising up to 10% of all of sporting injuries. Around 90% of such injuries are located in the lower limb. This articles aims to define the optimal management of lower limb stress fractures in the athlete, with a view to maximise return rates and minimise return times to sport. Treatment planning of this condition is specific to the location of the injury. However, there remains a clear division of stress fractures by “high” and “low” risk. “Low risk” stress fractures are those with a low probability of fracture propagation, delayed union, or non-union, and so can be managed reliably with rest and exercise limitation. These include stress fractures of the Postero-Medial Tibial Diaphysis, Metatarsal Shafts, Distal Fibula, Medial Femoral Neck, Femoral Shaft and Calcaneus. “High risk” stress fractures, in contrast, have increased rates of fracture propagation, displacement, delayed and non-union, and so require immediate cessation of activity, with orthopaedic referral, to assess the need for surgical intervention. These include stress fractures of the Anterior Tibial Diaphysis, Fifth Metatarsal Base, Medial Malleolus, Lateral Femoral Neck, Tarsal Navicular and Great Toe Sesamoids. In order to establish the optimal methods for managing these injuries, we present and review the current evidence which guides the treatment of stress fractures in athletes. From this, we note an increased role for surgical management of certain high risk stress fractures to improve return times and rates to sport. Following this, key recommendations are provided for the management of the common stress fracture types seen in the athlete. Five case reports are also presented to illustrate the application of sport-focussed lower limb stress fracture treatment in the clinical setting. PMID:28361017

  9. Lower limb stress fractures in sport: Optimising their management and outcome.

    Science.gov (United States)

    Robertson, Greg A J; Wood, Alexander M

    2017-03-18

    Stress fractures in sport are becoming increasing more common, comprising up to 10% of all of sporting injuries. Around 90% of such injuries are located in the lower limb. This articles aims to define the optimal management of lower limb stress fractures in the athlete, with a view to maximise return rates and minimise return times to sport. Treatment planning of this condition is specific to the location of the injury. However, there remains a clear division of stress fractures by "high" and "low" risk. "Low risk" stress fractures are those with a low probability of fracture propagation, delayed union, or non-union, and so can be managed reliably with rest and exercise limitation. These include stress fractures of the Postero-Medial Tibial Diaphysis, Metatarsal Shafts, Distal Fibula, Medial Femoral Neck, Femoral Shaft and Calcaneus. "High risk" stress fractures, in contrast, have increased rates of fracture propagation, displacement, delayed and non-union, and so require immediate cessation of activity, with orthopaedic referral, to assess the need for surgical intervention. These include stress fractures of the Anterior Tibial Diaphysis, Fifth Metatarsal Base, Medial Malleolus, Lateral Femoral Neck, Tarsal Navicular and Great Toe Sesamoids. In order to establish the optimal methods for managing these injuries, we present and review the current evidence which guides the treatment of stress fractures in athletes. From this, we note an increased role for surgical management of certain high risk stress fractures to improve return times and rates to sport. Following this, key recommendations are provided for the management of the common stress fracture types seen in the athlete. Five case reports are also presented to illustrate the application of sport-focussed lower limb stress fracture treatment in the clinical setting.

  10. Repeated Stress Fractures in an Amenorrheic Marathoner: A Case Conference.

    Science.gov (United States)

    Sutton, John R.; Nilson, Karen L.

    1989-01-01

    Presents a case conference by 2 experts on the relationship between a 26-year-old marathoner's amenorrhea and her sustained unusual stress fractures in 4 ribs (plus previous similar fractures of the calcaneal, navicular, metatarsal, and tibial bones). The experts conclude that she suffers many manifestations of overtraining. (SM)

  11. Nuclear scintigraphic evaluation of third metacarpal and metatarsal bone fractures in three horses

    International Nuclear Information System (INIS)

    Markel, M.D.; Snyder, J.R.; Hornof, W.J.; Meagher, D.M.

    1987-01-01

    Nuclear scintigraphy was used to evaluate healing of third metacarpal bone (MC III) fractures in 2 horses (horses 1 and 2) and a third metatarsal bone fracture in 1 horse (horse 3) after stabilization of each fracture with 2 broad dynamic compression plates. In horse 1, the fracture had uniform uptake of 99mTc methylene diphosphonate on days 1, 15, and 30 after surgery. The fracture healed, and the horse was discharged from the clinic on day 52. In horse 2, a 6-cm photopenic region (ie, area of low radioactivity) was seen over the diaphysis of MC III on day 3. The region persisted and became more distinct by day 32. The diaphysis of MC III sequestered, and horse 2 was euthanatized on day 44. In horse 3, vascularity was seen bridging the fracture on day 5, with a 3-cm photopenic region over the dorsal diaphysis of the third metatarsal bone. By days 18 and 32, uptake of 99mTc methylene diphosphonate in the region had increased, indicating vascularization of the site. the fracture healed, and horse 3 was discharged from the clinic on day 47. Our findings indicated that serial nuclear scintigraphy can be used to evaluate fracture vascularization after surgery in horses

  12. Stress fractures about the tibia, foot, and ankle.

    Science.gov (United States)

    Shindle, Michael K; Endo, Yoshimi; Warren, Russell F; Lane, Joseph M; Helfet, David L; Schwartz, Elliott N; Ellis, Scott J

    2012-03-01

    In competitive athletes, stress fractures of the tibia, foot, and ankle are common and lead to considerable delay in return to play. Factors such as bone vascularity, training regimen, and equipment can increase the risk of stress fracture. Management is based on the fracture site. In some athletes, metabolic workup and medication are warranted. High-risk fractures, including those of the anterior tibial diaphysis, navicular, proximal fifth metatarsal, and medial malleolus, present management challenges and may require surgery, especially in high-level athletes who need to return to play quickly. Noninvasive treatment modalities such as pulsed ultrasound and extracorporeal shock wave therapy may have some benefit but require additional research.

  13. Stress distribution of metatarsals during forefoot strike versus rearfoot strike: A finite element study.

    Science.gov (United States)

    Li, Shudong; Zhang, Yan; Gu, Yaodong; Ren, James

    2017-12-01

    Due to the limitations of experimental approaches, comparison of the internal deformation and stresses of the human man foot between forefoot and rearfoot landing is not fully established. The objective of this work is to develop an effective FE modelling approach to comparatively study the stresses and energy in the foot during forefoot strike (FS) and rearfoot strike (RS). The stress level and rate of stress increase in the Metatarsals are established and the injury risk between these two landing styles is evaluated and discussed. A detailed subject specific FE foot model is developed and validated. A hexahedral dominated meshing scheme was applied on the surface of the foot bones and skin. An explicit solver (Abaqus/Explicit) was used to stimulate the transient landing process. The deformation and internal energy of the foot and stresses in the metatarsals are comparatively investigated. The results for forefoot strike tests showed an overall higher average stress level in the metatarsals during the entire landing cycle than that for rearfoot strike. The increase rate of the metatarsal stress from the 0.5 body weight (BW) to 2 BW load point is 30.76% for forefoot strike and 21.39% for rearfoot strike. The maximum rate of stress increase among the five metatarsals is observed on the 1st metatarsal in both landing modes. The results indicate that high stress level during forefoot landing phase may increase potential of metatarsal injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Evaluation of transfixation casting for treatment of third metacarpal, third metatarsal, and phalangeal fractures in horses: 37 cases (1994-2004).

    Science.gov (United States)

    Lescun, Timothy B; McClure, Scott R; Ward, Michael P; Downs, Christopher; Wilson, David A; Adams, Stephen B; Hawkins, Jan F; Reinertson, Eric L

    2007-05-01

    To evaluate clinical findings, complications, and outcome of horses and foals with third metacarpal, third metatarsal, or phalangeal fractures that were treated with transfixation casting. Retrospective case series. Animals-29 adult horses and 8 foals with fractures of the third metacarpal or metatarsal bone or the proximal or middle phalanx. Medical records were reviewed, and follow-up information was obtained. Data were analyzed by use of logistic regression models for survival, fracture healing, return to intended use, pin loosening, pin hole lysis, and complications associated with pins. In 27 of 35 (77%) horses, the fracture healed and the horse survived, including 10 of 15 third metacarpal or metatarsal bone fractures, 11 of 12 proximal phalanx fractures, and 6 of 8 middle phalanx fractures. Four adult horses sustained a fracture through a pin hole. One horse sustained a pathologic unicortical fracture secondary to a pin hole infec-tion. Increasing body weight, fracture involving 2 joints, nondiaphyseal fracture location, and increasing duration until radiographic union were associated with horses not returning to their intended use. After adjusting for body weight, pin loosening was associated with di-aphyseal pin location, pin hole lysis was associated with number of days with a transfixation cast, and pin complications were associated with hand insertion of pins. Results indicated that transfixation casting can be successful in managing fractures distal to the carpus or tarsus in horses. This technique is most suitable for comminuted fractures of the proximal phalanx but can be used for third metacarpal, third metatarsal, or middle phalanx fractures, with or without internal fixation.

  15. Failed Surgical Management of Acute Proximal Fifth Metatarsal (Jones) Fractures: A Retrospective Case Series and Literature Review.

    Science.gov (United States)

    Granata, Jaymes D; Berlet, Gregory C; Philbin, Terrence M; Jones, Grant; Kaeding, Christopher C; Peterson, Kyle S

    2015-12-01

    Nonunion, delayed union, and refracture after operative treatment of acute proximal fifth metatarsal fractures in athletes is uncommon. This study was a failure analysis of operatively managed acute proximal fifth metatarsal fractures in healthy athletes. We identified 149 patients who underwent operative treatment for fifth metatarsal fractures. Inclusion criteria isolated skeletally mature, athletic patients under the age of 40 with a minimum of 1-year follow-up. Patients were excluded with tuberosity fractures, fractures distal to the proximal metaphyseal-diaphyseal region of the fifth metatarsal, multiple fractures or operative procedures, fractures initially treated conservatively, and medical comorbidities/risk factors for nonunion. Fifty-five patients met the inclusion/exclusion criteria. Four (7.3%) patients required a secondary operative procedure due to refracture. The average time to refracture was 8 months. All refractures were associated with bent screws and occurred in male patients who participated in professional basketball, professional volleyball, and college football. The average time for release to progressive weight-bearing was 6 weeks. Three patients were revised to a bigger size screw and went on to union. One patient was revised to the same-sized screw and required a second revision surgery for nonunion. All failures were refractures in competitive athletes who were initially treated with small diameter solid or cannulated stainless steel screws. The failures were not associated with early postoperative weight-bearing protocol. Maximizing initial fixation stiffness may decrease the late failure rate in competitive athletes. More clinical studies are needed to better understand risk factors for failure after screw fixation in the competitive, athletic population. Prognostic, Level IV: Case series. © 2015 The Author(s).

  16. Designing a Prognostic Scoring System for Predicting the Outcomes of Proximal Fifth Metatarsal Fractures at 20 Weeks

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Tahririan

    2015-03-01

    Full Text Available Background: Fractures of the proximal fifth metatarsal bone are among the most common fractures observed in the foot and their classification and management has been subject to much discussion and disagreement. In this study, we aim to identify and quantify the effect of possible predictors of the outcome of the treatment of proximal fifth metatarsal fractures. Methods: Patients with established proximal fifth metatarsal fractures were enrolled in this prospective cohort and the outcome of their treatment was assessed using the AOFAS mid foot scale at 6 and 20 weeks. Results: 143 patients were included in the study. Our study showed that displacement, weight and type III fractures were significant independent predictors of poor outcome at 6 weeks while at 20 weeks in addition to these factors, gender and diabetes mellitus were also shown to be significant independent predictors of poor outcome. A scoring system was designed by assigning weight to these factors and it was shown to be a strong predictor of outcome at 20 weeks. Conclusion: We recommend that our scoring system would help surgeons to decide whether patients’ prognostic factors are significant enough for him/her to opt for a surgical approach to treatment rather than a conservative approach.

  17. Expected Time to Return to Athletic Participation After Stress Fracture in Division I Collegiate Athletes.

    Science.gov (United States)

    Miller, Timothy L; Jamieson, Marissa; Everson, Sonsecharae; Siegel, Courtney

    2017-12-01

    Few studies have documented expected time to return to athletic participation after stress fractures in elite athletes. Time to return to athletic participation after stress fractures would vary by site and severity of stress fracture. Retrospective cohort study. Level 3. All stress fractures diagnosed in a single Division I collegiate men's and women's track and field/cross-country team were recorded over a 3-year period. Site and severity of injury were graded based on Kaeding-Miller classification system for stress fractures. Time to return to full unrestricted athletic participation was recorded for each athlete and correlated with patient sex and site and severity grade of injury. Fifty-seven stress fractures were diagnosed in 38 athletes (mean age, 20.48 years; range, 18-23 years). Ten athletes sustained recurrent or multiple stress fractures. Thirty-seven injuries occurred in women and 20 in men. Thirty-three stress fractures occurred in the tibia, 10 occurred in the second through fourth metatarsals, 3 occurred in the fifth metatarsal, 6 in the tarsal bones (2 navicular), 2 in the femur, and 5 in the pelvis. There were 31 grade II stress fractures, 11 grade III stress fractures, and 2 grade V stress fractures (in the same patient). Mean time to return to unrestricted sport participation was 12.9 ± 5.2 weeks (range, 6-27 weeks). No significant differences in time to return were noted based on injury location or whether stress fracture was grade II or III. The expected time to return to full unrestricted athletic participation after diagnosis of a stress fracture is 12 to 13 weeks for all injury sites. Athletes with grade V (nonunion) stress fractures may require more time to return to sport.

  18. Radiographic study of the fifth metatarsal for optimal intramedullary screw fixation of Jones fracture.

    Science.gov (United States)

    Ochenjele, George; Ho, Bryant; Switaj, Paul J; Fuchs, Daniel; Goyal, Nitin; Kadakia, Anish R

    2015-03-01

    Jones fractures occur in the relatively avascular metadiaphyseal junction of the fifth metatarsal (MT), which predisposes these fractures to delayed union and nonunion. Operative treatment with intramedullary (IM) screw fixation is recommended in certain cases. Incorrect screw selection can lead to refractures, nonunion, and cortical blowout fractures. A better understanding of the anatomy of the fifth MT could aid in preoperative planning, guide screw size selection, and minimize complications. We retrospectively identified foot computed tomographic (CT) scans of 119 patients that met inclusion criteria. Using interactive 3-dimensional (3-D) models, the following measurements were calculated: MT length, "straight segment length" (distance from the base of the MT to the shaft curvature), and canal diameter. The diaphysis had a lateroplantar curvature where the medullary canal began to taper. The average straight segment length was 52 mm, and corresponded to 68% of the overall length of the MT from its proximal end. The medullary canal cross-section was elliptical rather than circular, with widest width in the sagittal plane and narrowest in coronal plane. The average coronal canal diameter at the isthmus was 5.0 mm. A coronal diameter greater than 4.5 mm at the isthmus was present in 81% of males and 74% of females. To our knowledge, this is the first anatomic description of the fifth metatarsal based on 3-D imaging. Excessive screw length could be avoided by keeping screw length less than 68% of the length of the fifth metatarsal. A greater than 4.5 mm diameter screw might be needed to provide adequate fixation for most study patients since the isthmus of the medullary canal for most were greater than 4.5 mm. Our results provide an improved understanding of the fifth metatarsal anatomy to guide screw diameter and length selection to maximize screw fixation and minimize complications. © The Author(s) 2014.

  19. Diagnosis, treatment, and rehabilitation of stress fractures in the lower extremity in runners

    Science.gov (United States)

    Kahanov, Leamor; Eberman, Lindsey E; Games, Kenneth E; Wasik, Mitch

    2015-01-01

    Stress fractures account for between 1% and 20% of athletic injuries, with 80% of stress fractures in the lower extremity. Stress fractures of the lower extremity are common injuries among individuals who participate in endurance, high load-bearing activities such as running, military and aerobic exercise and therefore require practitioner expertise in diagnosis and management. Accurate diagnosis for stress fractures is dependent on the anatomical area. Anatomical regions such as the pelvis, sacrum, and metatarsals offer challenges due to difficulty differentiating pathologies with common symptoms. Special tests and treatment regimes, however, are similar among most stress fractures with resolution between 4 weeks to a year. The most difficult aspect of stress fracture treatment entails mitigating internal and external risk factors. Practitioners should address ongoing risk factors to minimize recurrence. PMID:25848327

  20. Stress fractures in military training

    International Nuclear Information System (INIS)

    Jofre, M.J.; Sierralta, M.P.

    2002-01-01

    During military training, the incidence of overuse injuries like stress fractures increase. The aim of the study was to investigate the utility of bone scan in a military population with clinical suspected stress fractures or periostitis. Material and methods: A three-year retrospective analysis was made on patients who were clinically diagnosed with stress fractures at the Military Hospital Nuclear Medicine Department. Thirty-seven patients were studied (mean age 23. +/- 8 y.o; 31 males), 28 cases of which (76%) had tibial stress syndrome. Other localizations were lumbar spine, femoral, fibular, tarsal or metatarsal. Bone scintigraphy was performed injecting 1036 MBq of Tc99m-MDP i.v. Whole body images and lateral projections of lower extremities were done. Results: Bone scan in tibial syndrome was positive for 23 cases (82%), 65% of them were bilateral and 13% also had femoral injuries. X-rays were done in 10 cases and were all negative. In other localizations, the bone scans were negative, but demonstrated other degenerative lesions. All stress fractures were conservatively treated with non-steroidal anti-inflammatories and suspension of physical activity. Conclusions: Bone scan is a reliable confirmatory tool for tibial stress syndrome diagnosis. In addition, it helps to determine both the severity and extension of the injury as well as support the indication of rest in the military population

  1. Stress fractures in military training

    Energy Technology Data Exchange (ETDEWEB)

    Jofre, M J; Sierralta, M P [Military Hospital Nuclear Medicine Department, Santiago (Chile)

    2002-09-01

    During military training, the incidence of overuse injuries like stress fractures increase. The aim of the study was to investigate the utility of bone scan in a military population with clinical suspected stress fractures or periostitis. Material and methods: A three-year retrospective analysis was made on patients who were clinically diagnosed with stress fractures at the Military Hospital Nuclear Medicine Department. Thirty-seven patients were studied (mean age 23. +/- 8 y.o; 31 males), 28 cases of which (76%) had tibial stress syndrome. Other localizations were lumbar spine, femoral, fibular, tarsal or metatarsal. Bone scintigraphy was performed injecting 1036 MBq of Tc99m-MDP i.v. Whole body images and lateral projections of lower extremities were done. Results: Bone scan in tibial syndrome was positive for 23 cases (82%), 65% of them were bilateral and 13% also had femoral injuries. X-rays were done in 10 cases and were all negative. In other localizations, the bone scans were negative, but demonstrated other degenerative lesions. All stress fractures were conservatively treated with non-steroidal anti-inflammatories and suspension of physical activity. Conclusions: Bone scan is a reliable confirmatory tool for tibial stress syndrome diagnosis. In addition, it helps to determine both the severity and extension of the injury as well as support the indication of rest in the military population.

  2. External fixation to correct tarsal-metatarsal fracture in rock pigeon (Columba livia

    Directory of Open Access Journals (Sweden)

    Leandro Almeida Rui

    Full Text Available ABSTRACT Orthopedic conditions, such as bone fractures, are very common in avian medicine. External fixators have been considered the gold standard for birds, since they allow early movement of the limbs and minimal invasive surgery. Fractures in several bones have been successfully treated in pigeons. However, to the best of our knowledge, this case represents the first report of successful surgical repair of tarsal-metatarsal fracture in rock pigeon. External fixator was made with four 24G catheters, being inserted manually proximal and distal to the fracture and connected with polymerizable acrylic. Radiographic consolidation of fracture was observed 60 days post-surgery and anti-inflammatory and antibiotic protocols were successful on avoiding pain and infection during surgery and bone healing.

  3. Salter-Harris type II metacarpal and metatarsal fracture in three foals. Treatment by minimally-invasive lag screw osteosynthesis combined with external coaptation.

    Science.gov (United States)

    Klopfenstein Bregger, Micaël D; Fürst, Anton E; Kircher, Patrick R; Kluge, Katharina; Kummer, Martin

    2016-05-18

    To describe minimally-invasive lag screw osteosynthesis combined with external coaptation for the treatment of Salter-Harris type II third metacarpal and third metatarsal bone fractures. Three foals aged two weeks to four months with a Salter-Harris type II third metacarpal or third metatarsal fracture. Surgery was carried out under general anaesthesia in lateral recumbency. After fracture reduction, the metaphyseal fragment was stabilized with two cortical screws placed in lag fashion under fluoroscopic control. A cast was applied for at least two weeks. All foals had a good outcome with complete fracture healing and return to complete soundness without any angular limb deformity. All foals had moderate transient digital hyperextension after cast removal. Internal fixation of Salter-Harris type II third metacarpal or third metatarsal fractures with two cortical screws in lag fashion, combined with external coaptation provided good stabilization and preserved the longitudinal growth potential of the injured physis.

  4. Radiographic classification for fractures of the fifth metatarsal base

    International Nuclear Information System (INIS)

    Mehlhorn, Alexander T.; Zwingmann, Joern; Hirschmueller, Anja; Suedkamp, Norbert P.; Schmal, Hagen

    2014-01-01

    Avulsion fractures of the fifth metatarsal base (MTB5) are common fore foot injuries. Based on a radiomorphometric analysis reflecting the risk for a secondary displacement, a new classification was developed. A cohort of 95 healthy, sportive, and young patients (age ≤ 50 years) with avulsion fractures of the MTB5 was included in the study and divided into groups with non-displaced, primary-displaced, and secondary-displaced fractures. Radiomorphometric data obtained using standard oblique and dorso-plantar views were analyzed in association with secondary displacement. Based on this, a classification was developed and checked for reproducibility. Fractures with a longer distance between the lateral edge of the styloid process and the lateral fracture step-off and fractures with a more medial joint entry of the fracture line at the MTB5 are at higher risk to displace secondarily. Based on these findings, all fractures were divided into three types: type I with a fracture entry in the lateral third; type II in the middle third; and type III in the medial third of the MTB5. Additionally, the three types were subdivided into an A-type with a fracture displacement <2 mm and a B-type with a fracture displacement ≥ 2 mm. A substantial level of interobserver agreement was found in the assignment of all 95 fractures to the six fracture types (κ = 0.72). The secondary displacement of fractures was confirmed by all examiners in 100 %. Radiomorphometric data may identify fractures at risk for secondary displacement of the MTB5. Based on this, a reliable classification was developed. (orig.)

  5. Radiographic classification for fractures of the fifth metatarsal base

    Energy Technology Data Exchange (ETDEWEB)

    Mehlhorn, Alexander T.; Zwingmann, Joern; Hirschmueller, Anja; Suedkamp, Norbert P.; Schmal, Hagen [University of Freiburg Medical Center, Department of Orthopaedic Surgery, Freiburg (Germany)

    2014-04-15

    Avulsion fractures of the fifth metatarsal base (MTB5) are common fore foot injuries. Based on a radiomorphometric analysis reflecting the risk for a secondary displacement, a new classification was developed. A cohort of 95 healthy, sportive, and young patients (age ≤ 50 years) with avulsion fractures of the MTB5 was included in the study and divided into groups with non-displaced, primary-displaced, and secondary-displaced fractures. Radiomorphometric data obtained using standard oblique and dorso-plantar views were analyzed in association with secondary displacement. Based on this, a classification was developed and checked for reproducibility. Fractures with a longer distance between the lateral edge of the styloid process and the lateral fracture step-off and fractures with a more medial joint entry of the fracture line at the MTB5 are at higher risk to displace secondarily. Based on these findings, all fractures were divided into three types: type I with a fracture entry in the lateral third; type II in the middle third; and type III in the medial third of the MTB5. Additionally, the three types were subdivided into an A-type with a fracture displacement <2 mm and a B-type with a fracture displacement ≥ 2 mm. A substantial level of interobserver agreement was found in the assignment of all 95 fractures to the six fracture types (κ = 0.72). The secondary displacement of fractures was confirmed by all examiners in 100 %. Radiomorphometric data may identify fractures at risk for secondary displacement of the MTB5. Based on this, a reliable classification was developed. (orig.)

  6. Fractures of the proximal fifth metatarsal: percutaneous bicortical fixation.

    Science.gov (United States)

    Mahajan, Vivek; Chung, Hyun Wook; Suh, Jin Soo

    2011-06-01

    Displaced intraarticular zone I and displaced zone II fractures of the proximal fifth metatarsal bone are frequently complicated by delayed nonunion due to a vascular watershed. Many complications have been reported with the commonly used intramedullary screw fixation for these fractures. The optimal surgical procedure for these fractures has not been determined. All these observations led us to evaluate the effectiveness of percutaneous bicortical screw fixation for treating these fractures. Twenty-three fractures were operatively treated by bicortical screw fixation. All the fractures were evaluated both clinically and radiologically for the healing. All the patients were followed at 2 or 3 week intervals till fracture union. The patients were followed for an average of 22.5 months. Twenty-three fractures healed uneventfully following bicortical fixation, with a mean healing time of 6.3 weeks (range, 4 to 10 weeks). The average American Orthopaedic Foot & Ankle Society (AOFAS) score was 94 (range, 90 to 99). All the patients reported no pain at rest or during athletic activity. We removed the implant in all cases at a mean of 23.2 weeks (range, 18 to 32 weeks). There was no refracture in any of our cases. The current study shows the effectiveness of bicortical screw fixation for displaced intraarticular zone I fractures and displaced zone II fractures. We recommend it as one of the useful techniques for fixation of displaced zone I and II fractures.

  7. [Stress fractures in disabled athletes' preparation for the paralympic games in Athens, 2004: an assessment].

    Science.gov (United States)

    Laboute, E; Druvert, J C; Pailler, D; Piera, J-B

    2008-03-01

    To identify stress fracture frequency and the associated risk factors in disabled female athletes preparing the Paralympic Games in Athens in 2004. The study is focused on four athletes (including one with a vision impairment) among the 31 women selected to participate in the Paralympic Games. The medical records of selected athletes not having been able to participate in the Games due to a stress fracture were analyzed. One case of stress fracture to the first metatarsal was reported of one below-knee amputee and an additional case to the second metatarsal of one hemiplegic athlete. Two of three athletes with physical disability were unable to participate in the Games because of stress fracture occurring during the preparatory phase. Among four athletes selected to take part in the Paralympic Games. If morphological predispositions are inherent to the sportswomen, the main favouring factor to be retained is their running asymmetry. Training programmes must therefore take this characteristic into account and must not offer heavy-load repetitive exercise (such as endurance or jogging) at the expense of technique. Over-intense training exposes the disabled athlete to this type of pathology and is likely to affect his chances of competing.

  8. High-Risk Stress Fractures: Diagnosis and Management.

    Science.gov (United States)

    McInnis, Kelly C; Ramey, Lindsay N

    2016-03-01

    Stress fractures are common overuse injuries in athletes. They occur during periods of increased training without adequate rest, disrupting normal bone reparative mechanisms. There are a host of intrinsic and extrinsic factors, including biochemical and biomechanical, that put athletes at risk. In most stress fractures, the diagnosis is primarily clinical, with imaging indicated at times, and management focused on symptom-free relative rest with advancement of activity as tolerated. Overall, stress fractures in athletes have an excellent prognosis for return to sport, with little risk of complication. There is a subset of injuries that have a greater risk of fracture progression, delayed healing, and nonunion and are generally more challenging to treat with nonoperative care. Specific locations of high-risk stress fracture include the femoral neck (tension side), patella, anterior tibia, medial malleolus, talus, tarsal navicular, proximal fifth metatarsal, and great toe sesamoids. These sites share a characteristic region of high tensile load and low blood flow. High-risk stress fractures require a more aggressive approach to evaluation, with imaging often necessary, to confirm early and accurate diagnosis and initiate immediate treatment. Treatment consists of nonweight-bearing immobilization, often with a prolonged period away from sport, and a more methodic and careful reintroduction to athletic activity. These stress fractures may require surgical intervention. A high index of suspicion is essential to avoid delayed diagnosis and optimize outcomes in this subset of stress fractures. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  9. [Stress reactions in bones of the foot in sport: diagnosis, assessment and therapy].

    Science.gov (United States)

    Miltner, O

    2013-06-01

    Stress reactions and stress fractures are defined as structural damage to bone caused by repetitive stress or stereotypical loading. The balance between loading and unloading of bone is disrupted in stress reactions and stress fractures through the sport-specific demands and by the exogenous or endogenous risk factors present. In sports orthopedics the localization of stress reactions and stress fractures are subdivided into high risk fractures and low risk fractures. Conventional diagnostic radiology can initially be inconclusive. With symptoms persisting over 2 weeks further diagnostics using magnetic resonance imaging (MRI) should be performed. In the area of the foot stress reactions and stress fractures can often occur bilaterally or multifocally and most commonly affect the second metatarsals followed by the third metatarsals. Fractures of the fifth metatarsal, second metatarsal base, medial malleolus as well as navicular and sesamoid fractures are high risk fractures requiring special clinical and radiological monitoring. Basically, conservative treatment using the 2-phase model is the treatment of choice. In delayed union or severe pain surgical treatment is indicated.

  10. Diagnosis, treatment, and rehabilitation of stress fractures in the lower extremity in runners

    Directory of Open Access Journals (Sweden)

    Kahanov L

    2015-03-01

    Full Text Available Leamor Kahanov,1 Lindsey E Eberman,2 Kenneth E Games,2 Mitch Wasik2 1College of Health Science, Misericordia University, Dallas, PA, USA; 2Department of Applied Medicine and Rehabilitation, Indiana State University, Terre Haute, IN, USA Abstract: Stress fractures account for between 1% and 20% of athletic injuries, with 80% of stress fractures in the lower extremity. Stress fractures of the lower extremity are common injuries among individuals who participate in endurance, high load-bearing activities such as running, military and aerobic exercise and therefore require practitioner expertise in diagnosis and management. Accurate diagnosis for stress fractures is dependent on the anatomical area. Anatomical regions such as the pelvis, sacrum, and metatarsals offer challenges due to difficulty differentiating pathologies with common symptoms. Special tests and treatment regimes, however, are similar among most stress fractures with resolution between 4 weeks to a year. The most difficult aspect of stress fracture treatment entails mitigating internal and external risk factors. Practitioners should address ongoing risk factors to minimize recurrence. Keywords: medial tibial stress syndrome, stress injury, nonunion stress fracture

  11. Intramedullary screw fixation with bone autografting to treat proximal fifth metatarsal metaphyseal-diaphyseal fracture in athletes: a case series

    Directory of Open Access Journals (Sweden)

    Tsukada Sachiyuki

    2012-07-01

    Full Text Available Abstract Background Delayed unions or refractures are not rare following surgical treatment for proximal fifth metatarsal metaphyseal-diaphyseal fractures. Intramedullary screw fixation with bone autografting has the potential to resolve the issue. The purpose of this study was to evaluate the result of the procedure. Methods The authors retrospectively reviewed 15 athletes who underwent surgical treatment for proximal fifth metatarsal metaphyseal-diaphyseal fracture. Surgery involved intramedullary cannulated cancellous screw fixation after curettage of the fracture site, followed by bone autografting. Postoperatively, patients remain non weight-bearing in a splint or cast for two weeks and without immobilization for an additional two weeks. Full weight-bearing was allowed six weeks postoperatively. Running was permitted after radiographic bone union, and return-to-play was approved after gradually increasing the intensity. Results All patients returned to their previous level of athletic competition. Mean times to bone union, initiation of running, and return-to-play were 8.4, 8.8, and 12.1 weeks, respectively. Although no delayed unions or refractures was observed, distal diaphyseal stress fractures at the distal tip of the screw occurred in two patients and a thermal necrosis of skin occurred in one patient. Conclusions There were no delayed unions or refractures among patients after carrying out a procedure in which bone grafts were routinely performed, combined with adequate periods of immobilization and non weight-bearing. These findings suggest that this procedure may be useful option for athletes to assuring return to competition level.

  12. Isolated avulsion fracture of the first metatarsal base at the peroneus longus tendon attachment: a case report.

    Science.gov (United States)

    Weinberg, Maxwell W; Krähenbühl, Nicola; Davidson, Nathan P; Hanrahan, Christopher J; Barg, Alexej

    2018-05-01

    Avulsion fractures of the first metatarsal (MT1) base at the peroneus longus (PL) tendon attachment are rare and may be undiagnosed during an emergency visit. If the injury is not treated properly, chronic pain or persistent impairment for inversion and plantar-flexion of the first ray may occur. This case report presents a 30-year-old woman who presented 10 weeks post trauma to a foot and ankle surgeon due to a swollen right midfoot with diffuse tenderness over the medial Lisfranc joint. Further evaluation showed an isolated avulsion fracture of the first metatarsal, which was undiagnosed during the emergent visit following the accident. In this case, the patient was successfully treated conservatively. The goal of this article is to raise awareness of this rare injury for radiologists and orthopedic surgeons.

  13. The radiological diagnosis of stress fracture

    International Nuclear Information System (INIS)

    Li Yonggang; Wang Renfa; Zhang Jingfeng; Wang Min

    2005-01-01

    Objective: To study the radiological features and biomechanics of stress fracture. Methods: The X-ray, CT, MRI, and ECT signs in 20 cases of stress fracture and its correlation to biomechanics were analyzed. Results: Of the 20 cases, 14 cases occurred in the tibia, 2 cases in the metatarsal bone, 1 case in the rib, 1 case in the neck of femur and ribs, 1 case in the middle-inferior part of the femur, and 1 case in the fibula. Tow early cases of stress fracture demonstrated a characteristic sign of 'gray cortex'. The spherical or abnormal generation of bony callus and periosteum proliferation that demonstrated 'double cortex' sign in 2 cases were the sign of bone remodeling and the 'button sign' was the sign of bone healing. CT scan could clearly show the pathologic changes of bone and the soft tissue edema. Bone callus showed low signal on T 1 WI and slight high signal on T 2 WI. The area of bone edema on MRI that demonstrated low signal on T 1 WI and high signal on T 2 WI was larger than that on CT. MRI showed a linear band of low signal on both T 1 WI and T 2 WI in the area of bone fracture. ECT showed a focal area of increased uptake in the abnormal areas. The areas of bone stress fracture were characteristic and accorded with the biomechanical weak area in the bone. Conclusion: Stress fracture occurs in the special parts of the bone and has characteristic imaging features. X-ray should still be used to find the fracture of bones in the first inspection. CT and MRI are very helpful in the differentiation. Although sensitive, bone scan has lower specificity than either CT or MRI. (authors)

  14. Defect nonunion of a metatarsal bone fracture in a cow: successful management with bone plating and autogenous cancellous bone graft.

    Science.gov (United States)

    Raghunath, M; Singh, N; Singh, T; Gopinathan, A; Mohindroo, J; Atri, K

    2013-01-01

    A two-and-half-year-old cow was presented with a defect nonunion of the right metatarsal III/IV bone following a severely comminuted open fracture two months previously. The animal underwent open fixation using a 4.5 mm, broad, 10-hole, dynamic compression plate and autogenous cancellous bone graft collected from the contralateral iliac shaft. The animal started partial weight bearing after the third postoperative day and resumed complete weight bearing after the 10th day. Fracture healing was complete and the implants were removed after the 120th postoperative day. Stable fixation by means of a bone plate in conjunction with a cancellous bone graft facilitated complete healing and restoration of the bone column of the defect and the metatarsal fracture. The animal made a complete recovery.

  15. Incidence and Time to Return to Training for Stress Fractures during Military Basic Training

    Directory of Open Access Journals (Sweden)

    Alexander M. Wood

    2014-01-01

    Full Text Available Currently, little is known about the length of time required to rehabilitate patients from stress fractures and their return to preinjury level of physical activity. Previous studies have looked at the return to sport in athletes, in a general population, where rehabilitation is not as controlled as within a captive military population. In this study, a longitudinal prospective epidemiological database was assessed to determine the incidence of stress fractures and the time taken to rehabilitate recruits to preinjury stage of training. Findings demonstrated a background prevalence of 5% stress fractures in Royal Marine training; femoral and tibial stress fractures take 21.1 weeks to return to training with metatarsal stress fractures being the most common injury taking 12.2 weeks. Rehabilitation from stress fractures accounts for 814 weeks of recruit rehabilitation time per annum. Stress fracture incidence is still common in military training; despite this stress fracture recovery times remain constant and represent a significant interruption in training. It takes on average 5 weeks after exercise specific training has restarted to reenter training at a preinjury level, regardless of which bone has a stress fracture. Further research into their prevention, treatment, and rehabilitation is required to help reduce these burdens.

  16. Percutaneous internal fixation of proximal fifth metatarsal jones fractures (Zones II and III) with Charlotte Carolina screw and bone marrow aspirate concentrate: an outcome study in athletes.

    Science.gov (United States)

    Murawski, Christopher D; Kennedy, John G

    2011-06-01

    Internal fixation is a popular first-line treatment method for proximal fifth metatarsal Jones fractures in athletes; however, nonunions and screw breakage can occur, in part because of nonspecific fixation hardware and poor blood supply. To report the results from 26 patients who underwent percutaneous internal fixation with a specialized screw system of a proximal fifth metatarsal Jones fracture (zones II and III) and bone marrow aspirate concentrate. Case series; Level of evidence, 4. Percutaneous internal fixation for a proximal fifth metatarsal Jones fracture (zones II and III) was performed on 26 athletic patients (mean age, 27.47 years; range, 18-47). All patients were competing at some level of sport and were assessed preoperatively and postoperatively using the Foot and Ankle Outcome Score and SF-12 outcome scores. The mean follow-up time was 20.62 months (range, 12-28). Of the 26 fractures, 17 were traditional zone II Jones fractures, and the remaining 9 were zone III proximal diaphyseal fractures. The mean Foot and Ankle Outcome Score significantly increased, from 51.15 points preoperatively (range, 14-69) to 90.91 at final follow-up (range, 71-100; P fracture healing on standard radiographs was 5 weeks after surgery (range, 4-24). Two patients did not return to their previous levels of sporting activity. One patient experienced a delayed union, and 1 healed but later refractured. Percutaneous internal fixation of proximal fifth metatarsal Jones fractures, with a Charlotte Carolina screw and bone marrow aspirate concentrate, provides more predictable results while permitting athletes a return to sport at their previous levels of competition, with few complications.

  17. Effect of Weight-Bearing in Conservative and Operative Management of Fractures of the Base of the Fifth Metatarsal Bone

    Directory of Open Access Journals (Sweden)

    Jae-Yong Park

    2017-01-01

    Full Text Available Background. There is no established principle regarding weight-bearing in conservative and operative management of fifth metatarsal base fractures. Methods. We reviewed 86 patients with acute fifth metatarsal base fractures. Conservatively treated late or early weight-bearing patients were assigned to Group A or C, respectively. Operatively treated late or early weight-bearing patients were assigned to Group B or D, respectively. Results were evaluated by clinical union, bone resorption, and the American Orthopaedic Foot and Ankle Society (AOFAS and Visual Analogue Scale (VAS scores. Results. All 4 groups had bone union at a mean of 6.9 weeks (range, 5.1–15.0. There were no differences between the groups in the AOFAS and VAS scores. In the early weight-bearing groups, there were fewer cases of bone resorption, and the bone unions periods were earlier. Conclusions. Early weight-bearing may help this patient population. Moreover, conservative treatment could be an option in patients with underlying diseases.

  18. Surgical management of complete diaphyseal third metacarpal and metatarsal bone fractures: Clinical outcome in 10 mature horses and 11 foals

    OpenAIRE

    Bischofberger, Andrea S; Fürst, Anton; Auer, Jörg A; Lischer, Christoph J

    2009-01-01

    Reasons for performing study: Osteosynthesis of third metacarpal (McIII) and third metatarsal (MtIII) bone fractures in horses is a surgical challenge and complications surrounding the repair are common. Retrospective studies evaluating surgical repair, complications and outcome are necessary to increase knowledge and improve success of long bone fracture repair in the horse. Objectives: To evaluate clinical findings, surgical repair, post operative complications and outcome of 10 mature h...

  19. FRACTURES OF THE FIFTH METATARSAL RESULTS OF THE EARLY OPERATIVE TREATMENT OF ACUTE DISPLACED FRACTURES

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    Slaviša Mihaljević

    2004-04-01

    Full Text Available Background. Fracture of the proximal 5th metatarsal bone (MTB reach almost 2% of all fractures of the foot. Conservative treatment is method of choice in almost all cases. Selected cases can benefit from acute surgery especially if the proximal fragment is severe displaced or the excessive articular step off is present.Materials and methods. In a 4 year period 14 patients were operated due to the acute fracture of proximal 5th MTB. All patients were treated in less than 2 weeks after the injury. 10 patients had base avulsion fracture in zone I and 4 had Jones fracture in zone II with dislocation of fragments? 5 mm, articular step off of 2 mm and 30% of articulation surface. We used tension bend wire in 9 cases (64%, partially threaded cancellous screw in 4 cases (28% and bone sutures in 1 case (7%. Postoperatively all patients used crutches with nonweight bearing for 4 weeks and afterwards partial weight bearing till the end of the treatment. All patients were practicing active exercises for ankle, foot and toes. The results were evaluated according to the Maryland Foot Score (MFS at least 20 months after injury.Results. 13 patients (93% were included in follow up. 12 patients were evaluated as excellent and only one as a good. All 13 patients have no or slight pain with no change in ADL or work ability. 9 patients (69% reached full functional result and 4 (31% patients had slight limitation during distance walk. Patients reached full weight bearing in average 7 weeks (5–13.Conclusions. Early operative treatment of selected cases allows fast return to preoperative activity without long term functional sequel. Both operative procedures, screw fixation and tension wire, yielded comparable and excellent end result.

  20. Frequency distributions of 174 fractures of the distal condyles of the third metacarpal and metatarsal bones in 167 Thoroughbred racehorses (1999-2009).

    Science.gov (United States)

    Jacklin, B D; Wright, I M

    2012-11-01

    Although fractures of the metacarpal and metatarsal condyles are the most common long-bone fractures of Thoroughbred horses in training, limited data on variations in morphology and incidence have been published. Additionally, grouped analyses of previous studies from the UK and USA would permit comparison between study groups and the creation of a substantial pool of international data. Retrospective analysis of case records of horses with fractures of the distal condyles of third metacarpal/metatarsal bones seen over the last 10 years at Newmarket Equine Hospital. The current series was compared with a prior series from the UK; pooled analyses of these, and series from the USA were also compared. One hundred and seventy-four fractures were identified in 167 racehorses. The current series contained a significantly lower proportion of medial condylar fractures than in a similar population 17 years earlier. Fractures that originated more abaxially tended to be shorter, and a significant proportion of lateral condylar fractures arose outside of the condylar groove. There was also some apparent seasonality of fractures of the lateral condyles in 2-year-old horses, but not so in older horses or those with medial condylar fractures. A substantial portion (approximately 50%) of fractures in the present series cannot be explained by unifying theories of aetiopathogenesis, which suggest that fractures usually arise within the condylar groove, as a focus of cumulative fatigue and failure of adaptation of bone. A separate aetiopathogenesis may be responsible for a proportion of condylar fractures encountered in racehorses, and further work is required to elucidate this. Changes in the number of medial condylar fractures encountered may reflect the introduction of artificial racing and training surfaces, and also may reflect changes in the age demographic of horses racing in the UK since the introduction of year-round 'all-weather' racing. © 2012 EVJ Ltd.

  1. Successful fifth metatarsal bulk autograft reconstruction of thermal necrosis post intramedullary fixation.

    Science.gov (United States)

    Veljkovic, Andrea; Le, Vu; Escudero, Mario; Salat, Peter; Wing, Kevin; Penner, Murray; Younger, Alastair

    2018-03-21

    Reamed intramedullary (IM) screw fixation for proximal fifth metatarsal fractures is technically challenging with potentially devastating complications if basic principles are not followed. A case of an iatrogenic fourth-degree burn after elective reamed IM screw fixation of a proximal fifth metatarsal fracture in a high-level athlete is reported. The case was complicated by postoperative osteomyelitis with third-degree soft-tissue defect. This was successfully treated with staged autologous bone graft reconstruction, tendon reconstruction, and local bi-pedicle flap coverage. The patient returned to competitive-level sports, avoiding the need for fifth ray amputation. Critical points of the IM screw technique and definitive reconstruction are discussed. Bulk autograft reconstruction is a safe and effective alternative to ray amputation in segmental defects of the fifth metatarsal.Level of evidence V.

  2. Stress Fractures

    Science.gov (United States)

    Stress fractures Overview Stress fractures are tiny cracks in a bone. They're caused by repetitive force, often from overuse — such as repeatedly jumping up and down or running long distances. Stress fractures can also arise from normal use of ...

  3. Aircast walking boot and below-knee walking cast for avulsion fractures of the base of the fifth metatarsal: a comparative cohort study.

    Science.gov (United States)

    Shahid, Mohammad Kamran; Punwar, Shahid; Boulind, Caroline; Bannister, Gordon

    2013-01-01

    Acute avulsion fractures of the base of the fifth metatarsal are common and are treated in a variety of ways. The aims of this study were to compare pain, functional outcome, and time taken off work after treatment with a walking boot or a short-leg cast. Of 39 patients with acute avulsion fractures of the base of the fifth metatarsal, 23 were treated with a short-leg cast and 16 with a walking boot, according to the preference of the consultant present at outpatient clinic. Functional outcome was assessed by the Visual Analogue Scale Foot and Ankle Questionnaire (VAS FA), pain, and other complaints on presentation and at 3, 6, 9, and 12 weeks after injury. The VAS FA scores were compared between the 2 groups by a paired Student t test. The mean time to return to the level of pain and function before injury was approximately 9 weeks after treatment in the walking boot group and 12 weeks with a short-leg cast. Patients with walking boots reported less pain between 3 and 12 weeks than did those with short-leg casts after 6 (P = .06), 9 (P = .020), and 12 weeks (P = .33). Function was significantly better with Aircast walking boots after 3 (P = .006), 6 (P = .002), and 9 weeks (P = .002) but not after 12 weeks (P = .09). Patients returned to their preinjury level of driving after 6 weeks with walking boots and 12 weeks with short-leg casts (P = .006). Employed patients took a mean of 35.8 days off work (range, 28-42 days), fewer with boots (31.5 days) than with short-leg casts (39.2 days). The walking boot was better treatment than a short-leg cast for avulsion fractures of the base of the fifth metatarsal. Patients had an improved combined level of pain and function 3 weeks earlier, at 9 weeks post injury, when managed in a walking boot. Level II, prospective comparative series.

  4. Comparison of stress fractures of male and female recruits during basic training in the Israeli anti-aircraft forces.

    Science.gov (United States)

    Gam, Arnon; Goldstein, Liav; Karmon, Yuval; Mintser, Igor; Grotto, Itamar; Guri, Alex; Goldberg, Avishay; Ohana, Nissim; Onn, Erez; Levi, Yehezkel; Bar-Dayan, Yaron

    2005-08-01

    In military basic training, stress fractures are a common orthopedic problem. Female recruits have a significantly higher incidence of stress fractures than do male recruits. Because the Israeli Defense Forces opened traditionally male roles in combat units to female recruits, their high risk for stress fractures is of concern. To compare the prevalence of stress fractures during Israeli Defense Forces anti-aircraft basic training among otherwise healthy young male and female recruits, in terms of anatomic distribution and severity. Ten mixed gender batteries, including 375 male recruits and 138 female recruits, carried out basic training in the Israeli anti-aircraft corps between November 1999 and January 2003. Each battery was monitored prospectively for 10 weeks of a basic training course. During that time, recruits who were suspected of having an overuse injury went through a protocol that included an orthopedic specialist physical examination followed by a radionuclide technetium bone scan, which was assessed by consultant nuclear medicine experts. The assessment included the anatomic site and the severity of the fractures, labeled as either high severity or low severity. Stress fractures were significantly more common among female recruits than among male recruits. A total of 42 male (11.2%) and 33 female (23.91%) recruits had positive bone scans for stress fractures (female:male relative ratio, 2.13; p < 0.001). Pelvic, femur, and tibia fractures were significantly more common among female recruits than among male recruits (p < 0.005). Female recruits had significantly more severe fractures in the tibia (p < 0.05). However, there was no significant difference in the severity of stress fractures in the femur or metatarsals between male and female recruits, as assessed by radionuclide uptake. We recommend that different training programs be assigned according to gender, in which female recruits would have a lower level of target strain or a more moderate

  5. Traumatic Foot Fractures in Hard Working Donkeys

    Directory of Open Access Journals (Sweden)

    M.A. Semieka

    2012-10-01

    Full Text Available The present study was carried out on 45 hard working donkeys suffering from different types of traumatic foot fractures. These animals were selected from the clinical cases admitted to the Veterinary Teaching Hospital, Assiut University during the period of 2007-2010. Based on history, clinical signs and radiographic examination, various types of traumatic foot fractures were diagnosed and recorded. These fractures were affect metacarpal bones (N. =16, metatarsal bones (N. =9, proximal phalanx (N. = 13, middle phalanx (N. = 3, distal phalanx (N. = 2 and proximal sesamoid bones (N. = 2. It could be concluded that fractures of the large metacarpal bones are the most common types followed by fractures of the proximal phalanx of the thoracic limb then fractures of the metatarsal bones. Fractures of the middle phalanx, distal phalanx and proximal sesamoid bone are less common in donkeys. Single fractures of the metacarpal and metatarsal bones are more common than comminuted one, in addition diaphyseal fractures of these bones are more common than metaphyseal or epiphyseal fractures. In the proximal phalanx, comminuted fractures are more common than single fractures.

  6. Effect on Clinical Outcome and Growth Factor Synthesis With Adjunctive Use of Pulsed Electromagnetic Fields for Fifth Metatarsal Nonunion Fracture: A Double-Blind Randomized Study.

    Science.gov (United States)

    Streit, Adam; Watson, B Collier; Granata, Jaymes D; Philbin, Terrence M; Lin, Hsuan-Ni; O'Connor, J Patrick; Lin, Sheldon

    2016-09-01

    Electromagnetic bone growth stimulators have been found to biologically enhance the bone healing environment, with upregulation of numerous growth factors. The purpose of the study was to quantify the effect, in vivo, of pulsed electromagnetic fields (PEMFs) on growth factor expression and healing time in fifth metatarsal nonunions. This was a prospective, randomized, double-blind trial of patients, cared for by 2 fellowship-trained orthopedic foot and ankle surgeons. Inclusion criteria consisted of patients between 18 and 75 years old who had been diagnosed with a fifth metatarsal delayed or nonunion, with no progressive signs of healing for a minimum of 3 months. Eight patients met inclusion criteria and were randomized to receive either an active stimulation or placebo PEMF device. Each patient then underwent an open biopsy of the fracture site and was fitted with the appropriate PEMF device. The biopsy was analyzed for messenger-ribonucleic acid (mRNA) levels using quantitative competitive reverse transcription polymerase chain reaction (QT-RT-PCR). Three weeks later, the patient underwent repeat biopsy and open reduction and internal fixation of the nonunion site. The patients were followed at 2- to 4-week intervals with serial radiographs and were graded by the number of cortices of healing. All fractures healed, with an average time to complete radiographic union of 14.7 weeks and 8.9 weeks for the inactive and active PEMF groups, respectively. A significant increase in placental growth factor (PIGF) level was found after active PEMF treatment (P = .043). Other factors trended higher following active PEMF including brain-derived neurotrophic factor (BDNF), bone morphogenetic protein (BMP) -7, and BMP-5. The adjunctive use of PEMF for fifth metatarsal fracture nonunions produced a significant increase in local placental growth factor. PEMF also produced trends toward higher levels of multiple other factors and faster average time to radiographic union

  7. The Epidemiology of Stress Fractures in Collegiate Student-Athletes, 2004-2005 Through 2013-2014 Academic Years.

    Science.gov (United States)

    Rizzone, Katherine H; Ackerman, Kathryn E; Roos, Karen G; Dompier, Thomas P; Kerr, Zachary Y

    2017-10-01

    Stress fractures are injuries caused by cumulative, repetitive stress that leads to abnormal bone remodeling. Specific populations, including female athletes and endurance athletes, are at higher risk than the general athletic population. Whereas more than 460 000 individuals participate in collegiate athletics in the United States, no large study has been conducted to determine the incidence of stress fractures in collegiate athletes.   To assess the incidence of stress fractures in National Collegiate Athletic Association (NCAA) athletes and investigate rates and patterns overall and by sport.   Descriptive epidemiology study.   National Collegiate Athletic Association institutions.   National Collegiate Athletic Association athletes.   Data were analyzed from the NCAA Injury Surveillance Program for the academic years 2004-2005 through 2013-2014. We calculated rates and rate ratios (RRs) with 95% confidence intervals (CIs).   A total of 671 stress fractures were reported over 11 778 145 athlete-exposures (AEs) for an overall injury rate of 5.70 per 100 000 AEs. The sports with the highest rates of stress fractures were women's cross-country ( 28.59/100  000 AEs), women's gymnastics ( 25.58/100  000 AEs), and women's outdoor track ( 22.26/100  000 AEs). Among sex-comparable sports (baseball/softball, basketball, cross-country, ice hockey, lacrosse, soccer, swimming and diving, tennis, indoor track, and outdoor track), stress fracture rates were higher in women (9.13/100 000 AEs) than in men (4.44/100 000 AEs; RR = 2.06; 95% CI = 1.71, 2.47). Overall, stress fracture rates for these NCAA athletes were higher in the preseason (7.30/100 000 AEs) than in the regular season (5.12/100 000 AEs; RR = 1.43; 95% CI = 1.22, 1.67). The metatarsals (n = 254, 37.9%), tibia (n = 147, 21.9%), and lower back/lumbar spine/pelvis (n = 81, 12.1%) were the most common locations of injury. Overall, 21.5% (n = 144) of stress fractures were

  8. Diagnosis and Management of Common Foot Fractures.

    Science.gov (United States)

    Bica, David; Sprouse, Ryan A; Armen, Joseph

    2016-02-01

    Foot fractures are among the most common foot injuries evaluated by primary care physicians. They most often involve the metatarsals and toes. Patients typically present with varying signs and symptoms, the most common being pain and trouble with ambulation. Diagnosis requires radiographic evaluation, although emerging evidence demonstrates that ultrasonography may be just as accurate. Management is determined by the location of the fracture and its effect on balance and weight bearing. Metatarsal shaft fractures are initially treated with a posterior splint and avoidance of weight-bearing activities; subsequent treatment consists of a short leg walking cast or boot for four to six weeks. Proximal fifth metatarsal fractures have different treatments depending on the location of the fracture. A fifth metatarsal tuberosity avulsion fracture can be treated acutely with a compressive dressing, then the patient can be transitioned to a short leg walking boot for two weeks, with progressive mobility as tolerated after initial immobilization. A Jones fracture has a higher risk of nonunion and requires at least six to eight weeks in a short leg non-weight-bearing cast; healing time can be as long as 10 to 12 weeks. Great toe fractures are treated with a short leg walking boot or cast with toe plate for two to three weeks, then a rigid-sole shoe for an additional three to four weeks. Lesser toe fractures can be treated with buddy taping and a rigid-sole shoe for four to six weeks.

  9. Anatomic variations in the nutrient foramina of the equine third metatarsal bone in two horses

    International Nuclear Information System (INIS)

    Godshalk, C.P.; Kneller, S.K.; Daniel, G.B.

    1985-01-01

    An unusual presentation of the nutrient foramen of the third metatarsal bone (Mt-3) is described in two horses. In the first horse, the nutrient foramen was located ectopically in the dorsolateral cortex of Mt-3. The metatarsal nutrient foramina of the second horse were in the usual plantar location, but one was atypical in configuration. Clinical signs did not appear to be associated with these findings in either horse. The possibility of misdiagnosing a fracture rather than an ectopic nutrient foramen is discussed

  10. Metatarsal Osteotomies: Complications.

    Science.gov (United States)

    Reddy, Veerabhadra Babu

    2018-03-01

    Metatarsal osteotomies can be divided into proximal and distal. The proximal osteotomies, such as the oblique, segmental, set cut, and Barouk-Rippstein-Toullec (BRT) osteotomy, all provide the ability to significantly change the position of the metatarsal head without violating the joint. These osteotomies, however, have a high rate of nonunion when done without internal fixation and can lead to transfer metatarsalgia when done without regard to the parabola of metatarsal head position. Distal osteotomies such as the Weil and Helal offer superior healing but have an increased incidence of recurrent metatarsalgia, joint stiffness, and floating toe. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Stress fracture of the femoral neck in a child (stress fracture)

    International Nuclear Information System (INIS)

    Coldwell, D.; Gross, G.W.; Boal, D.K.

    1984-01-01

    Femoral neck stress fracture is extremely rare in childhood. We report a case of femoral neck stress fracture in an 11-year-old girl. Differentials diagnosis and a brief review of the literature follow. (orig.)

  12. Internal fixation of proximal fractures of the 2nd and 4th metacarpal and metatarsal bones using bioabsorbable screws.

    Science.gov (United States)

    Mageed, M; Steinberg, T; Drumm, N; Stubbs, N; Wegert, J; Koene, M

    2018-03-01

    Fractures involving the proximal one-third of the splint bone are relatively rare and are challenging to treat. A variety of management techniques have been reported in the literature. The aim of this retrospective case series was to describe the clinical presentation and evaluate the efficacy of bioabsorbable polylactic acid screws in internal fixation of proximal fractures of the 2nd and 4th metacarpal and metatarsal bones in horses. The medical records, diagnostic images and outcome of all horses diagnosed with a proximal fracture of the splint bones and treated with partial resection and internal fixation of the proximal stump using bioabsorbable polylactic acid screws between 2014 and 2015 were reviewed. Eight horses met the inclusion criteria. The results showed that there were no complications encountered during screw placement or postoperatively. Six horses returned to full work 3 months after the operation and two horses remained mildly lame. On follow-up radiographs 12 months postoperatively (n = 2) the screws were not completely absorbed. The screws resulted in a cone-shaped radiolucency, which was progressively replaced from the outer margins by bone sclerosis. The use of bioabsorbable screws for fixation of proximal fractures of the splint bone appears to be a safe and feasible technique and may offer several advantages over the use of traditional metallic implants. © 2018 Australian Veterinary Association.

  13. Mini-Invasive floating metatarsal osteotomy for resistant or recurrent neuropathic plantar metatarsal head ulcers.

    Science.gov (United States)

    Tamir, Eran; Finestone, Aharon S; Avisar, Erez; Agar, Gabriel

    2016-07-11

    Patients with peripheral neuropathy and pressure under a relatively plantar deviated metatarsal head frequently develop plantar foot ulcers. When conservative management with orthotics and shoes does not cure the ulcer, surgical metatarsal osteotomy may be indicated to relieve the pressure and enable the ulcer to heal. The purpose of this study is to evaluate the use of a mini-invasive floating metatarsal osteotomy in treating recalcitrant ulcers or recurrent ulcers plantar to the metatarsal heads in patients with diabetes mellitus (DM) related neuropathy. Computerized medical files of patients with diabetic neuropathy treated with an osteotomy during 2013 and 2014 were retrospectively reviewed. There were 20 osteotomies performed on 17 patients (mean age 58 years). The patients had a diagnosis of DM for a mean of 17 years. All ulcers were University of Texas grade 1A; mean ulcer age was 19 months. After 17/20 operations, the ulcer completely resolved after 6 weeks and did not recur after a mean follow-up of 11.5 months. One patient developed an early post-operative infection with osteomyelitis at the osteotomy site (proximal shaft of the fifth metatarsal) that needed debridement and IV antibiotics. In the other 19 cases, the surgical wound healed within 1 week. Asymptomatic radiological non-union developed in six cases (30 %). Mini-invasive floating metatarsal osteotomy can cure resistant and recurrent University of Texas grade 1A ulcerations plantar to the metatarsal heads in neuropathic patients.

  14. Stress fractures

    International Nuclear Information System (INIS)

    Berquist, T.H.; Cooper, K.L.; Pritchard, D.J.

    1985-01-01

    The diagnosis of a stress fracture should be considered in patients presented with pain after a change in activity, especially if the activity is strenuous and the pain is in the lower extremities. Since evidence of the stress fracture may not be apparent for weeks on routine radiographs, proper use of other imaging techniques will allow an earlier diagnosis. Prompt diagnosis is especially important in the femur, where displacement may occur

  15. Mini-Invasive floating metatarsal osteotomy for resistant or recurrent neuropathic plantar metatarsal head ulcers

    OpenAIRE

    Tamir, Eran; Finestone, Aharon S.; Avisar, Erez; Agar, Gabriel

    2016-01-01

    Background Patients with peripheral neuropathy and pressure under a relatively plantar deviated metatarsal head frequently develop plantar foot ulcers. When conservative management with orthotics and shoes does not cure the ulcer, surgical metatarsal osteotomy may be indicated to relieve the pressure and enable the ulcer to heal. The purpose of this study is to evaluate the use of a mini-invasive floating metatarsal osteotomy in treating recalcitrant ulcers or recurrent ulcers plantar to the ...

  16. A lateral approach to the repair of propagating fractures of the medial condyle of the third metacarpal and metatarsal bone in 18 racehorses.

    Science.gov (United States)

    Wright, Ian M; Smith, Matthew R W

    2009-08-01

    To report the technique, observations on fracture configurations and results of treatment by fixation lag screw following the fracture plane determined by an approach to the third metacarpal/metatarsal bone (MC3/MT3) that begins laterally over the metacarpo(metatarso)phalangeal joint and extends dorsally over the diaphysis of the bone. Case series. Thoroughbred horses (n=18) with propagating fractures of the medial condyle of MC3/MT3. Retrospective analysis of case records of horses with fractures of the medial condyle of MC3/MT3 that propagated sagittaly or in a spiral configuration into the diaphysis, repaired surgically under general anesthesia by screw fixation in lag fashion through a lateral approach with periosteal reflection. Fractures were readily identified at surgery, enabling screw fixation in lag fashion following the fracture plane. Fracture configurations varied and could be classified as sagittal and spiral fractures with fractures within each group generally following a similar course. All horses recovered relatively uneventfully from general anesthesia and surgery, and all fractures healed well. Thirteen horses returned to training; 5 subsequently raced. Repair of propagating sagittal and spiral fractures of the medial condyle of MC3/MT3 with diaphyseal involvement, through a lateral approach with periosteal reflection permits stable fixation with minimal complications. In this series there were no catastrophic failures. Fractures of the medial condyle of MC3/MT3 that propagate either sagittaly or in a spiral configuration into the diaphysis can be successfully repaired with screw fixation in lag fashion using a lateral approach with periosteal reflection.

  17. Surgical management of complete diaphyseal third metacarpal and metatarsal bone fractures: clinical outcome in 10 mature horses and 11 foals.

    Science.gov (United States)

    Bischofberger, A S; Fürst, A; Auer, J; Lischer, C

    2009-05-01

    Osteosynthesis of third metacarpal (McIII) and third metatarsal (MtIII) bone fractures in horses is a surgical challenge and complications surrounding the repair are common. Retrospective studies evaluating surgical repair, complications and outcome are necessary to increase knowledge and improve success of long bone fracture repair in the horse. To evaluate clinical findings, surgical repair, post operative complications and outcome of 10 mature horses and 11 foals with McIII or MtIII fractures that were treated with open reduction and internal fixation (ORIF). Medical records were reviewed and follow-up information obtained by means of radiographs and/or telephone questionnaire. Survival was achieved in 62% of the horses (3 mature/10 foals). On long-term evaluation (> 6 months) 11 horses (2 mature/9 foals) were fit for their intended activity, one mature horse had a chronic low grade lameness, and one foal was lost to follow-up because it was sold. The main fracture types were simple transverse (333%) or simple oblique (28.6%) and 71.4% of the fractures were open, 3 Type I (one mature/2 foals) and 12 type II (7 mature/5 foals). The preoperative assessment revealed inadequate emergency treatment in 10 horses (5 mature/5 foals; 47.6%). Survival rate of horses with open fractures was 12.5% (1/8) in mature and 85.7% (6/7) in foals. Post operative incisional infection (4 mature, 3 foals) was only managed successfully in 2 foals. Fracture instability related to inadequate fracture fixation technique occurred in 4 horses (all mature) and was always associated with unsuccessful outcome. Age, bodyweight and infection are strongly associated with outcome in treatment of complete McIII/MtIII fractures. Rigid fixation using plates and screws can be successful in treatment of closed or open, complete diaphyseal McIII/MtIII fractures in mature horses and foals. Instable fixation, infection and a bodyweight > 320 kg are major risk factors for unsuccessful outcome.

  18. Stress fractures in athletes

    International Nuclear Information System (INIS)

    Kirschberger, R.; Henning, A.; Graff, K.H.

    1984-01-01

    The early exclusion of the presence of a stress fracture may be decisive for the success of an athlete. Scintigraphy with a bone-seeking radiopharmaceutical is suitable for the early detection of stress lesions. Of 30 athletes, fractures were demonstrated in 17 whereas in 6 they were excluded. We found most fractures in the tarsal bones such as os naviculare pedis, ossa cuneiformia and talus. The type of sport engaged in appears to be an important factor in determining the location of the fracture. Scintiphotos were taken in several views using region of interest techniques and two phase-scintigraphy. This method is considered to be useful for localization and follow-up of skeletal stress lesions as well as for differential diagnosis. (orig.) [de

  19. Stress fractures in athletes

    Energy Technology Data Exchange (ETDEWEB)

    Kirschberger, R; Henning, A; Graff, K H

    1984-12-01

    The early exclusion of the presence of a stress fracture may be decisive for the success of an athlete. Scintigraphy with a bone-seeking radiopharmaceutical is suitable for the early detection of stress lesions. Of 30 athletes, fractures were demonstrated in 17 whereas in 6 they were excluded. We found most fractures in the tarsal bones such as os naviculare pedis, ossa cuneiformia and talus. The type of sport engaged in appears to be an important factor in determining the location of the fracture. Scintiphotos were taken in several views using region of interest techniques and two phase-scintigraphy. This method is considered to be useful for localization and follow-up of skeletal stress lesions as well as for differential diagnosis.

  20. Bone stress in runners with tibial stress fracture.

    Science.gov (United States)

    Meardon, Stacey A; Willson, John D; Gries, Samantha R; Kernozek, Thomas W; Derrick, Timothy R

    2015-11-01

    Combinations of smaller bone geometry and greater applied loads may contribute to tibial stress fracture. We examined tibial bone stress, accounting for geometry and applied loads, in runners with stress fracture. 23 runners with a history of tibial stress fracture & 23 matched controls ran over a force platform while 3-D kinematic and kinetic data were collected. An elliptical model of the distal 1/3 tibia cross section was used to estimate stress at 4 locations (anterior, posterior, medial and lateral). Inner and outer radii for the model were obtained from 2 planar x-ray images. Bone stress differences were assessed using two-factor ANOVA (α=0.05). Key contributors to observed stress differences between groups were examined using stepwise regression. Runners with tibial stress fracture experienced greater anterior tension and posterior compression at the distal tibia. Location, but not group, differences in shear stress were observed. Stepwise regression revealed that anterior-posterior outer diameter of the tibia and the sagittal plane bending moment explained >80% of the variance in anterior and posterior bone stress. Runners with tibial stress fracture displayed greater stress anteriorly and posteriorly at the distal tibia. Elevated tibial stress was associated with smaller bone geometry and greater bending moments about the medial-lateral axis of the tibia. Future research needs to identify key running mechanics associated with the sagittal plane bending moment at the distal tibia as well as to identify ways to improve bone geometry in runners in order to better guide preventative and rehabilitative efforts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Stress fractures and bone pain

    International Nuclear Information System (INIS)

    Groshar, D.; Even-Sapir, E.; Lam, M.; Israel, O.; Front, D.

    1984-01-01

    Stress fractures result from an unusual repetitive physical activity causing absorption of bone in excess of repair and bone formation. This leads to the weakening of the bone and subsequently to a fracture. It is a benign condition that if recognized in time does not need any treatment besides rest. However, if diagnosis is not made and physical activity continues it may result in severe injury to the bone and a frank fracture may result. Pain is the typical clinical feature and bone scintigraphy, being more sensitive than radiography, is done to establish early diagnosis. The presence of asymptomatic sites of abnormal bone uptake typical of stress fracture in which pain appeared only about 2 weeks after scintigraphy, drew the authors' attention to the question of how close is the relationship between stress fractures and bone pain. Sixty-four military recruits diagnosed as suffering from stress fracture were investigated in order to correlate sites with abnormal uptake of Tc-99m MDP on bone scintigraphy with sites of local pain. In 37 (58%) subjects multiple sites of abnormal uptake were recognised. Of 123 sites of abnormal uptake, 31 (25%) were asymptomatic. In three patients bone pain appeared at the site of the abnormal uptake two weeks after scintigraphy. Bone scintigraphy appears to be more sensitive than bone pain in the diagnosis of stress fractures. The osteoblastic activity which manifests itself by abnormal uptake appears in some cases earlier than the pain caused by the fracture. Present findings may suggest that under certain circumstances, in a population prone to stress fracture, bone scan should be considered as a screening method

  2. Distinguishing stress fractures from pathologic fractures: a multimodality approach

    International Nuclear Information System (INIS)

    Fayad, Laura M.; Kamel, Ihab R.; Kawamoto, Satomi; Bluemke, David A.; Fishman, Elliot K.; Frassica, Frank J.

    2005-01-01

    Whereas stress fractures occur in normal or metabolically weakened bones, pathologic fractures occur at the site of a bone tumor. Unfortunately, stress fractures may share imaging features with pathologic fractures on plain radiography, and therefore other modalities are commonly utilized to distinguish these entities. Additional cross-sectional imaging with CT or MRI as well as scintigraphy and PET scanning is often performed for further evaluation. For the detailed assessment of a fracture site, CT offers a high-resolution view of the bone cortex and periosteum which aids the diagnosis of a pathologic fracture. The character of underlying bone marrow patterns of destruction can also be ascertained along with evidence of a soft tissue mass. MRI, however, is a more sensitive technique for the detection of underlying bone marrow lesions at a fracture site. In addition, the surrounding soft tissues, including possible involvement of adjacent muscle, can be well evaluated with MRI. While bone scintigraphy and FDG-PET are not specific, they offer a whole-body screen for metastases in the case of a suspected malignant pathologic fracture. In this review, we present select examples of fractures that underscore imaging features that help distinguish stress fractures from pathologic fractures, since accurate differentiation of these entities is paramount. (orig.)

  3. Nontraumatic femur fracture in an oligomenorrheic athlete.

    Science.gov (United States)

    Dugowson, C E; Drinkwater, B L; Clark, J M

    1991-12-01

    Exercise-associated amenorrhea is the cessation of menses in a woman following onset of training or an increase in training intensity. Its physiologic basis is characterized by consistently low levels of gonadotropin and ovarian hormones, but the underlying cause of this phenomenon is unknown. Although osteopenia has been described in amenorrheic women athletes, it has been primarily a laboratory diagnosis. Several recent studies have described a significantly lower bone mineral density (BMD) in the lumbar spine of amenorrheic athletes. Marcus et al. also reported an increased number of metatarsal and tibial stress fractures in a group of amenorrheic women. We report here the first case of a nontraumatic femur fracture in an amenorrheic athlete. A 32-yr-old white female, with four prior fibular stress fractures, suffered a left femoral shaft fracture during the 13th mile of a half-marathon. The fracture was successfully internally fixed. Biochemical studies showed no metabolic abnormality. Bone mineral density of the lumbar spine, femoral neck, tibia, and fibula were below the mean for both eumenorrheic and amenorrheic female athletes. Exercise-associated amenorrhea is a medical problem that may have serious implications for both competitive and high-intensity recreational female athletes.

  4. Fracture criteria of reactor graphite under multiaxial stresses

    International Nuclear Information System (INIS)

    Sato, S.; Kawamata, K.; Kurumada, A.; Oku, T.

    1987-01-01

    New fracture criteria for graphite under multiaxial stresses are presented for designing core and support materials of a high temperature gas cooled reactor. Different kinds of fracture strength tests are carried out for a near isotropic graphite IG-11. Results show that, under the stress state in which tensile stresses are predominant, the maximum principal stress theory is seen as applicable for brittle fracture. Under the stress state in which compressive stresses are predominant there may be two fracture modes for brittle fracture, namely, slipping fracture and mode II fracture. For the former fracture mode the maximum shear stress criterion is suitable, but for the latter fracture mode a new mode II fracture criterion including a restraint effect for cracks is verified to be applicable. Also a statistical correction for brittle fracture criteria under multiaxial stresses is discussed. By considering the allowable stress values for safe design, the specified minimum ultimate strengths corresponding to a survival probability of 99% at the 95% confidence level are presented. (orig./HP)

  5. Risk factors for stress fractures.

    Science.gov (United States)

    Bennell, K; Matheson, G; Meeuwisse, W; Brukner, P

    1999-08-01

    Preventing stress fractures requires knowledge of the risk factors that predispose to this injury. The aetiology of stress fractures is multifactorial, but methodological limitations and expediency often lead to research study designs that evaluate individual risk factors. Intrinsic risk factors include mechanical factors such as bone density, skeletal alignment and body size and composition, physiological factors such as bone turnover rate, flexibility, and muscular strength and endurance, as well as hormonal and nutritional factors. Extrinsic risk factors include mechanical factors such as surface, footwear and external loading as well as physical training parameters. Psychological traits may also play a role in increasing stress fracture risk. Equally important to these types of analyses of individual risk factors is the integration of information to produce a composite picture of risk. The purpose of this paper is to critically appraise the existing literature by evaluating study design and quality, in order to provide a current synopsis of the known scientific information related to stress fracture risk factors. The literature is not fully complete with well conducted studies on this topic, but a great deal of information has accumulated over the past 20 years. Although stress fractures result from repeated loading, the exact contribution of training factors (volume, intensity, surface) has not been clearly established. From what we do know, menstrual disturbances, caloric restriction, lower bone density, muscle weakness and leg length differences are risk factors for stress fracture. Other time-honoured risk factors such as lower extremity alignment have not been shown to be causative even though anecdotal evidence indicates they are likely to play an important role in stress fracture pathogenesis.

  6. The first metatarsal web space: its applied anatomy and usage in tracing the first dorsal metatarsal artery in thumb reconstruction.

    Science.gov (United States)

    Xu, Yong-Qing; Li, Jun; Zhong, Shi-Zhen; Xu, Da-Chuan; Xu, Xiao-Shan; Guo, Yuan-Fa; Wang, Xin-Min; Li, Zhu-Yi; Zhu, Yue-Liang

    2004-12-01

    To clarify the anatomical relationship of the structures in the first toe webbing space for better dissection of toes in thumb reconstruction. The first dorsal metatarsal artery, the first deep transverse metatarsal ligament and the extensor expansion were observed on 42 adult cadaveric lower extremities. Clinically the method of tracing the first dorsal metatarsal artery around the space of the extensor expansion was used in 36 cases of thumb reconstruction. The distal segments of the first dorsal metatarsal artery of Gilbert types I and II were located superficially to the extensor expansion. The harvesting time of a toe was shortened from 90 minutes to 50 minutes with 100% survival of reconstructed fingers. The distal segment of the first dorsal metatarsal artery lies constantly at the superficial layer of the extensor expansion. Most of the first metatarsal arteries of Gilbert types I and II can be easily located via the combined sequential and reverse dissection around the space of the extensor expansion.

  7. Stress fractures in elite cross-country athletes.

    Science.gov (United States)

    Laker, Scott R; Saint-Phard, Deborah; Tyburski, Mark; Van Dorsten, Brent

    2007-04-01

    This retrospective and comparative survey investigates an unusual number of stress fractures seen within a Division I college cross-country team. An anonymous questionnaire-designed to observe factors known to increase stress fracture incidence-was distributed to members of the current and previous seasons' teams. Running surface, sleep hours, intake of calcium, and shoe type were among the factors investigated. Eleven lower extremity stress fractures were found in nine athletes. Athletes with stress fractures reported significantly fewer workouts per week on the new track. All other study parameters had no statistically significant effect on stress fractures in these athletes.

  8. Anam Cara, St Canice's Road, Glasnevin, Dublin 11.

    LENUS (Irish Health Repository)

    O'Neill, Barry J

    2014-04-01

    Antiphospholipid syndrome and systemic erythematosus have been associated with metatarsal stress fractures. Stress fractures of the Lisfranc joint complex are uncommon injuries but have been reported to occur most frequently in ballet dancers. We present a case of an avulsion fracture of the Lisfranc joint complex that occurred spontaneously. We have reviewed the association between systemic conditions and metatarsal fractures and proposed a series of hypothetical pathological events that may have contributed to this unusual injury.

  9. Osteossíntese com parafuso intramedular nas fraturas proximais do quinto metatarsiano do atleta Intramedullary screw fixation of proximal fifth metatarsal fractures in athletes

    Directory of Open Access Journals (Sweden)

    Marta Maria Teixeira de Oliveira Massada

    2012-01-01

    Full Text Available OBJETIVO: Avaliar os resultados clínicos e radiológicos da osteossíntese com parafuso de compressão intramedular nas fraturas proximais do quinto metatarsiano no atleta. MÉTODOS: Foram incluídos no estudo 11 homens e seis mulheres com diagnóstico de fratura das zonas II e III do quinto metatarsiano. Quinze dos pacientes praticavam esporte a nível profissional ou de alto rendimento (futebol: n=11; basquetebol: n=1; atletismo: n=3 e dois praticavam atividade esportiva regular a nível recreacional. Foram submetidos a fixação cirúrgica com parafuso canulado de compressão (4.5mm de diâmetro. Todos os pacientes foram avaliados clinicamente e através da revisão do processo clínico e dos estudos imagiológicos. O tempo médio de seguimento após a cirurgia foi 54 meses (38-70. RESULTADOS: O tempo médio de consolidação (como demonstrado pelo estudo radiológico e de retorno à atividade esportiva foi 7.3 e 7.5 semanas, respectivamente. Todos os atletas retornaram aos níveis de atividade prévios. Não verificamos atrasos de consolidação, não-união ou refraturas à data do estudo. CONCLUSÃO: A osteossíntese com parafuso de compressão intramedular nas fraturas proximais do quinto metatarsiano demonstrou, nos nossos pacientes, ser um procedimento eficaz com taxas de morbilidade muito reduzidas e que permite ao atleta um retorno precoce à atividade esportiva. Nível de evidência I, Série de Casos.OBJECTIVE: The purpose of this study was to review the short- and long-term clinical and radiological results of intramedullary compression screw fixation of proximal fifth metatarsal fractures in athletes. METHODS: Eleven male and six female active patients with fifth metatarsal zone II and zone III fractures fixed with a 4.5-mm cannulated compression screw were evaluated by chart review, review of radiographs, and clinical evaluation. Fifteen of the patients were high-level athletes (soccer: n=11; basketball: n=1; track and field: n

  10. Analysis of 213 currently used rehabilitation protocols in foot and ankle fractures.

    Science.gov (United States)

    Pfeifer, Christian G; Grechenig, Stephan; Frankewycz, Borys; Ernstberger, Antonio; Nerlich, Michael; Krutsch, Werner

    2015-10-01

    Fractures of the ankle, hind- and midfoot are amongst the five most common fractures. Besides initial operative or non-operative treatment, rehabilitation of the patients plays a crucial role for fracture union and long term functional outcome. Limited evidence is available with regard to what a rehabilitation regimen should include and what guidelines should be in place for the initial clinical course of these patients. This study therefore investigated the current rehabilitation concepts after fractures of the ankle, hind- and midfoot. Written rehabilitation protocols provided by orthopedic and trauma surgery institutions in terms of recommendations for weight bearing, range of motion (ROM), physiotherapy and choice of orthosis were screened and analysed. All protocols for lateral ankle fractures type AO 44A1, AO 44B1 and AO 44C1, for calcaneal fractures and fractures of the metatarsal as well as other not specific were included. Descriptive analysis was carried out and statistical analysis applied where appropriate. 209 rehabilitation protocols for ankle fractures type AO 44B1 and AO 44C1, 98 for AO 44A1, 193 for metatarsal fractures, 142 for calcaneal fractures, 107 for 5(th) metatarsal base fractures and 70 for 5(th) metatarsal Jones fractures were evaluated. The mean time recommended for orthosis treatment was 6.04 (SD 0.04) weeks. While the majority of protocols showed a trend towards increased weight bearing and increased ROM over time, the best consensus was noted for weight bearing recommendations. Our study shows that there exists a huge variability in rehabilitation of fractures of the ankle-, hind- and midfoot. This may be contributed to a lack of consensus (e.g. missing publication of guidelines), individualized patient care (e.g. in fragility fractures) or lack of specialization. This study might serve as basis for prospective randomized controlled trials in order to optimize rehabilitation for these common fractures. Copyright © 2015 Elsevier Ltd

  11. Stress fractures in the lower extremity

    International Nuclear Information System (INIS)

    Berger, Ferco H.; Jonge, Milko C. de; Maas, Mario

    2007-01-01

    Stress fractures are fatigue injuries of bone usually caused by changes in training regimen in the population of military recruits and both professional and recreational athletes. Raised levels of sporting activity in today's population and refined imaging technologies have caused a rise in reported incidence of stress fractures in the past decades, now making up more than 10% of cases in a typical sports medicine practice. Background information (including etiology, epidemiology, clinical presentation and treatment and prevention) as well as state of the art imaging of stress fractures will be discussed to increase awareness amongst radiologists, providing the tools to play an important role in diagnosis and prognosis of stress fractures. Specific fracture sites in the lower extremity will be addressed, covering the far majority of stress fracture incidence. Proper communication between treating physician, physical therapist and radiologist is needed to obtain a high index of suspicion for this easily overlooked entity. Radiographs are not reliable for detection of stress fractures and radiologist should not falsely be comforted by them, which could result in delayed diagnosis and possibly permanent consequences for the patient. Although radiographs are mandatory to rule out differentials, they should be followed through when negative, preferably by magnetic resonance imaging (MRI), as this technique has proven to be superior to bone scintigraphy. CT can be beneficial in a limited number of patients, but should not be used routinely

  12. Pedicular stress fracture in the lumbar spine

    International Nuclear Information System (INIS)

    Chong, V.F.H.; Htoo, M.M.

    1997-01-01

    Spondylolisthesis with or without spondylolysis is common in the lumbar spine. Associated fracture in the pedicle ('pediculolysis') is unusual. The margins of pedicular stress fractures, like spondylolysis, usually appear sclerotic. A patient with a pedicular stress fracture with minimal marginal sclerosis suggesting an injury of recent onset is presented here. There was associated bilateral spondylolysis. The findings in this patient suggest that established pediculolysis probably represents a stress fracture that has failed to heal. (authors)

  13. Dynamic compression plate (DCP) fixation of propagating medial condylar fractures of the third metacarpal/metatarsal bone in 30 racehorses: retrospective analysis (1990-2005).

    Science.gov (United States)

    Goodrich, L R; Nixon, A J; Conway, J D; Morley, P S; Bladon, B M; Hogan, P M

    2014-11-01

    An in-depth review of dynamic compression plate (DCP) fixation of propagating medial condyle fractures of the third metacarpus or metatarsus has not been previously reported. To describe the technique, evaluate short-term outcome and long-term race performance of racehorses that underwent DCP fixation for repair of propagating or spiralling medial condylar fractures of the third metacarpal (McIII) or metatarsal (MtIII) bone. Retrospective case series. The surgical case records of 30 horses with propagating fractures of the medial condyle of McIII or MtIII were reviewed. Medical information included: age, breed, sex, presentation, how injury occurred (racing or training), surgical treatment and post operative complications. Racing information included: starts, top 3 placing and career earnings. Long propagating fractures of the medial condyle of Mc/tIII were identified in 23 Thoroughbred (TB) and 7 Standardbred (STB) racehorses. The fracture spiralled proximally in 22 of 30 cases (73%). Standardbreds had a higher propensity for hindlimb involvement (71%), whereas TBs tended to have more front limb involvement (61%). Twelve of 30 (40%) horses raced post surgery. Career earnings were significantly lower for TB horses with medial condylar fractures; $34,916 when compared with the national average of $60,841 (P≤0.03). Overall, horses having DCP fixation for medial condylar fractures had less starts post surgery (3.1 TBs and 5.8 STBs) compared with the national average (7 TBs and 17.3 STBs) and decreased lifetime starts 13.4 (TBs) compared with 17.3 nationally. Propagating medial condyle fractures can be repaired with plate fixation to potentially lessen the risk of catastrophic fracture destabilisation and return to racing can be expected in 40% of horses. Further prospective studies are warranted comparing lag screw fixation with DCP fixation for repair of severe medial condylar fractures of the metacarpus/metatarsus. © 2013 The Authors. Equine Veterinary Journal

  14. Fracture patterns and stresses in granite

    International Nuclear Information System (INIS)

    Price, N.J.

    1979-01-01

    If granite bodies are to be used as receptacles for toxic waste materials, the presence or absence of barren fractures and the virgin stresses in the granite are of fundamental importance. Unfortunately, very little is known regarding the incidence of fractures, or stresses, which exist at depths (of about 1 km) in granite bodies. A simple analysis is presented of a hypothetical intrusion which indicates the magnitudes of stresses and the possible fracture development which may be expected in such bodies. (auth)

  15. Pedicular stress fracture in the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Chong, V.F.H.; Htoo, M.M. [Singapore General Hospital, Singapore, (Singapore). Department of Diagnostic Radiology

    1997-08-01

    Spondylolisthesis with or without spondylolysis is common in the lumbar spine. Associated fracture in the pedicle (`pediculolysis`) is unusual. The margins of pedicular stress fractures, like spondylolysis, usually appear sclerotic. A patient with a pedicular stress fracture with minimal marginal sclerosis suggesting an injury of recent onset is presented here. There was associated bilateral spondylolysis. The findings in this patient suggest that established pediculolysis probably represents a stress fracture that has failed to heal. (authors). 10 refs., 2 figs.

  16. Tratamento cirúrgico das fraturas dos metatársicos laterais com técnica percutânea anterógrada: descrição técnica e resultados clínicos Anterograde percutaneous treatment of lesser metatarsal fractures: technical description and clinical results

    Directory of Open Access Journals (Sweden)

    Daniel Baumfeld

    2012-01-01

    Full Text Available OBJETIVO: O objetivo deste trabalho é avaliar os resultados obtidos com a técnica de fixação anterógrada percutânea para o tratamento das fraturas do colo e diáfise dos metatársicos laterais. MÉTODOS: Realizamos avaliação prospectiva de 14 pacientes operados no período de 2003 a 2008, em que foram levados em consideração a topografia das fraturas, o mecanismo de trauma, as comorbidades associadas e o escore AOFAS para o antepé. RESULTADOS: A região anatômica mais atingida foi o colo dos metatársicos (79%; o acometimento de múltiplos metatársicos ( 53% foi mais comum que o acometimento isolado (47%; o trauma de baixa energia (79% foi mais frequente do que o de alta energia (21%; pacientes do sexo feminino com diabetes mellitus apresentaram os piores resultados funcionais pós-operatórios. Não foram encontradas complicações pós-operatórias relacionadas com o tipo de tratamento instituído. CONCLUSÕES: A técnica cirúrgica apresentada demonstrou ser eficiente para o tratamento das fraturas dos metatarsos laterais com menor índice de complicações do que as técnicas já existentes na literatura.OBJECTIVE: The aim of this study was to evaluate the results obtained using the anterograde percutaneous fixation technique for treating shaft and neck fractures of the lesser metatarsals. METHODS: We prospectively evaluated 14 patients between 2003 and 2008, taking into consideration the topography of the fracture, trauma mechanism, associated comorbidities and AOFAS score for the forefoot. RESULTS: The anatomical region most affected was the metatarsal neck (79%. Involvement of multiple metatarsals (53% was more common than isolated fractures (47%. Low-energy trauma (79% was more frequent than high-energy trauma (21%. Female patients with diabetes had the worst postoperative functional results. There were no postoperative complications relating to the type of treatment instituted. CONCLUSIONS: The surgical technique presented

  17. Jogger's fracture and other stress fractures of the lumbo-sacral spine

    International Nuclear Information System (INIS)

    Abel, M.S.

    1985-01-01

    The posterior rings of the lower lumbo-sacral vertebrae are subject to stress fractures at any part - pedicle, pars, or lamina. The site of fracture is apparently determined by the axis of weight bearing. The three illustrative clinical examples cited include a jogger with a laminar fracture, a ballet dancer with pedicle fractures, and a nine-year-old boy with fractures of pars and lamina. Chronic low back pain is the typical complaint with stress fractures of the lower lumbo-sacral spine. Special imaging techniques are usually needed to demonstrate these lesions, including vertebral arch views, multi-directional tomography, and computed tomography (CT). (orig.)

  18. Rare stress fracture: longitudinal fracture of the femur.

    Science.gov (United States)

    Pérez González, M; Velázquez Fragua, P; López Miralles, E; Abad Moretón, M M

    42-year-old man with pain in the posterolateral region of the right knee that began while he was running. Initially, it was diagnosed by magnetic resonance (MR) as a possible aggressive process (osteosarcoma or Ewing's sarcoma) but with computed tomography it was noted a cortical hypodense linear longitudinal image with a continuous, homogeneous and solid periosteal reaction without clear soft tissue mass that in this patient suggest a longitudinal distal femoral fatigue stress fracture. This type of fracture at this location is very rare. Stress fractures are entities that can be confused with an agressive process. MR iscurrently the most sensitive and specific imaging method for its diagnosis. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Surgical repair of propagating condylar fractures of the third metacarpal/metatarsal bones with cortical screws placed in lag fashion in 26 racehorses (2007-2015).

    Science.gov (United States)

    Moulin, N; François, I; Coté, N; Alford, C; Cleary, O; Desjardins, M R

    2018-01-19

    Despite the recommendation of plate fixation for propagating condylar fractures of the third metacarpal (McIII) or third metatarsal bone (MtIII), lag screw fixation can be a viable surgical option. To evaluate short-term outcome and long-term racing performance of horses that underwent lag screw fixation of long condylar fractures of the McIII/MtIII. Retrospective case series. Medical records, post-surgical racing performance and outcome of 26 horses with propagating fractures of the medial and/or lateral condyle of McIII/MtIII were reviewed. Medical information included were age, breed, sex, physical examination at admission, circumstances of fracture, radiographic evaluation, anaesthesia and recovery records, surgical and post-operative management, as well as complications. Outcome included racing data and information from telephone interviews. Twenty-six horses (9 Standardbreds and 17 Thoroughbreds) were admitted with a long condylar fracture of the McIII/MtIII. Fore- and hindlimbs were equally represented with the left hindlimb being more frequently involved. Most of the fractures had a spiralling component (76%) and four (15%) were comminuted. Fifteen (58%) horses raced post-surgery including nine Standardbreds (100%) and six Thoroughbreds (35%). Twelve of them were placed in at least one race and 11 won at least once. One horse sustained a severe complication in recovery. No significant difference was observed in the racing performances before and after surgery. Follow-up method and duration were not standardised and there is a low number of cases with six surgeons. Long condylar fractures can be repaired using lag fashion technique combined with a half-limb or full-limb tight cast for recovery as a good surgical alternative. Similar results to plate fixation can be expected, with a return to racing of more than 50%, and the prognosis being even better for pacers. © 2018 EVJ Ltd.

  20. Analysis of fracture patterns and local stress field variations in fractured reservoirs

    Science.gov (United States)

    Deckert, Hagen; Drews, Michael; Fremgen, Dominik; Wellmann, J. Florian

    2010-05-01

    A meaningful qualitative evaluation of permeabilities in fractured reservoirs in geothermal or hydrocarbon industry requires the spatial description of the existing discontinuity pattern within the area of interest and an analysis how these fractures might behave under given stress fields. This combined information can then be used for better estimating preferred fluid pathway directions within the reservoir, which is of particular interest for defining potential drilling sites. A description of the spatial fracture pattern mainly includes the orientation of rock discontinuities, spacing relationships between single fractures and their lateral extent. We have examined and quantified fracture patterns in several outcrops of granite at the Costa Brava, Spain, and in the Black Forest, Germany, for describing reservoir characteristics. For our analysis of fracture patterns we have used photogrammetric methods to create high-resolution georeferenced digital 3D images of outcrop walls. The advantage of this approach, compared to conventional methods for fracture analysis, is that it provides a better 3D description of the fracture geometry as the entity of position, extent and orientation of single fractures with respect to their surrounding neighbors is conserved. Hence for instance, the method allows generating fracture density maps, which can be used for a better description of the spatial distribution of discontinuities in a given outcrop. Using photogrammetric techniques also has the advantage to acquire very large data sets providing statistically sound results. To assess whether the recorded discontinuities might act as fluid pathways information on the stress field is needed. A 3D model of the regional tectonic structure was created and the geometry of the faults was put into a mechanical 3D Boundary Element (BE) Model. The model takes into account the elastic material properties of the geological units and the orientation of single fault segments. The

  1. Computed tomography of stress fracture

    International Nuclear Information System (INIS)

    Murcia, M.; Brennan, R.E.; Edeiken, J.

    1982-01-01

    An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activites but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic. (orig.)

  2. Computed tomography of stress fracture

    International Nuclear Information System (INIS)

    Murcia, M.; Brennan, R.E.; Edeiken, J.

    1982-01-01

    An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activites but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic

  3. Percutaneous dorsal closing wedge osteotomy of the metatarsal neck in management of metatarsalgia.

    Science.gov (United States)

    Lui, Tun Hing

    2014-12-01

    Metatarsalgia can be caused by plantarflexion of a central metatarsal or discrepancies in the metatarsals' length. Nonsurgical management is usually sufficient to achieve satisfactory results. For those recalcitrant cases, metatarsal osteotomy is needed to relieve the pain. We describe a technique of percutaneous dorsal closing wedge osteotomy of the metatarsal to manage the recalcitrant metatarsalgia. A case series was reviewed retrospectively. From March 2010 to March 2013, percutaneous dorsal closing wedge osteotomy of the metatarsal neck has been performed in 33 patients. Thirty six feet with 63 metatarsals were operated on. Thirty two second metatarsals, 22 third metatarsals, 5 fourth metatarsals and 4 fifth metatarsals were operated on. All the osteotomy sites healed up without any transverse plane deformity. The painful callosities subsided except in one operated metatarsal. Recurrence of painful callosities occurred in 2 operated metatarsals. Transfer metatarsalgia occurred in 2 feet. Floating toe deformity occurred in 2 operated rays. There was no nerve injury noted. Two patients had delayed wound healing with serous discharge and the wounds were eventually healed up with wound dressing. Percutaneous dorsal closing wedge osteotomy of the metatarsal neck is an effective and safe surgical treatment of recalcitrant metatarsalgia. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. CANDIDATE GENE ANALYSIS IN ISRAELI SOLDIERS WITH STRESS FRACTURES

    Directory of Open Access Journals (Sweden)

    Ran Yanovich

    2012-03-01

    Full Text Available To investigate the association of polymorphisms within candidate genes which we hypothesized may contribute to stress fracture predisposition, a case-control, cross- sectional study design was employed. Genotyping 268 Single Nucleotide Polymorphisms- SNPs within 17 genes in 385 Israeli young male and female recruits (182 with and 203 without stress fractures. Twenty-five polymorphisms within 9 genes (NR3C1, ANKH, VDR, ROR2, CALCR, IL6, COL1A2, CBG, and LRP4 showed statistically significant differences (p < 0.05 in the distribution between stress fracture cases and non stress fracture controls. Seventeen genetic variants were associated with an increased stress fracture risk, and eight variants with a decreased stress fracture risk. None of the SNP associations remained significant after correcting for multiple comparisons (false discovery rate- FDR. Our findings suggest that genes may be involved in stress fracture pathogenesis. Specifically, the CALCR and the VDR genes are intriguing candidates. The putative involvement of these genes in stress fracture predisposition requires analysis of more cases and controls and sequencing the relevant genomic regions, in order to define the specific gene mutations

  5. Development of stress-modified fracture strain criterion for ductile fracture of API X65 steel

    International Nuclear Information System (INIS)

    Oh, Chang Kyun; Kim, Yun Jae; Park, Jin Moo; Kim, Woo Sik; Baek, Jong Hyun

    2005-01-01

    This paper presents a stress-modified fracture strain for API X65 steel used for gas pipeline, as a function of stress triaxiality. To determine the stress-modified fracture strain, tension test of bars with four different notch radii, made of API X65 steel, is firstly performed, from which true fracture strains are determined as a function of notch radius. Then detailed elastic-plastic, large strain Finite Element (FE) analyses are performed to estimate variations of stress triaxiality in the notched bars with load. Combining experimental with FE results provides the true fracture strain as a function of stress triaxiality, which is regarded as a criterion of ductile fracture. Application of the developed stress-modified fracture strain to failure prediction of gas pipes made of API X65 steel with various types of defects is discussed

  6. STRESS FRACTURE PREVALENCE IN ELITE FIGURE SKATERS

    Directory of Open Access Journals (Sweden)

    Sanda Dubravcic-Simunjak

    2008-09-01

    Full Text Available Figure skating is a physically demanding sport that requires a unique combination of artistic ability, speed, agility, flexibility and power. During the last decades not only the competitive schedule has become tougher, but after introduction of the new judging system in 2003, also more emphasis is put on difficult technical elements, jumps, steps and spins (ISU Rules, 2006. More studies about possible increasing prevalence of stress fractures in figure skaters and contributing factors are lacking (Dubravcic-Simunjak et al., 2003; Moran, 2000; Pecina et al., 1990. Therefore the aim of this study was to obtain data about the current stress fracture cumulative risk among elite junior and senior figure skaters, as well as possible factors that may contribute to stress fracture incidence. An anonymous questionnaire, divided into 5 sections, inquired about the prevalence of stress fracture were mailed and distributed to all 62 International Skating Union (ISU members by the ISU headquarters in Lausanne, Switzerland. The guidelines of the Helsinki declaration 2004 were followed. From the 644 skaters who received the questionnaire, 412 completed ones were returned from 110 female juniors (78 single skaters, 12 pair skaters and 20 ice dancers and 135 female seniors (97 single skaters, 16 pair skaters and 22 ice dancers and from 79 male juniors (47 single skaters, 12 pair skaters and 20 ice dancers and 88 male seniors (50 single skaters, 16 pair skaters and 22 ice dancers, coming from different ISU members. The response rate was 62% in females and 67% in males. The median age for female skaters was 16 years and for males 18 years (range 12-25 years. All participants started to skate between 3 and 6 years of age and started to compete in national and international competitions when they were between 5 and 7 years old. At the time of this analysis, they had been skating between 9 and 20 years.In females 41 (16.7%, and in males 25 (13.8% figure skaters

  7. Structural variation of the distal condyles of the third metacarpal and third metatarsal bones in the horse

    International Nuclear Information System (INIS)

    Riggs, C.M.; Whitehouse, G.H.; Boyde, A.

    1999-01-01

    This study examined 3-dimensional (3D) distribution of sectors with contrasting density in the equine third metacarpal (McIII) and third metatarsal (MtIII) bones with a view to explaining the aetiology of distal condylar fractures. Macroradiography and computed tomographic (CT) imaging were used in the nondestructive study of bones obtained from horses, most of which were Thoroughbreds in race training. Distal condylar regions of McIII and MtIII were also studied in microradiographs of 100 mu m thick mediolateral sections cut perpendicular to the dorsal and palmar/plantar articular surfaces. Qualitative and quantitative results from all methods used (radiography, CTand microradiographic stereology) demonstrated densification (sclerosis) of subchondral bone located in the palmar/plantar regions of the medial and lateral condyles of both McIII and MtIII, Substantial density gradients between the denser condyles and the subchondral bone of the sagittal groove were shown to equate with anatomical differences in loading intensity during locomotion. It is hypothesised that such differences in bone density results in stress concentration at the palmar/plantar aspect of the condylar grooves, which may predispose to fracture

  8. Anomalous Transport in Natural Fracture Networks Induced by Tectonic Stress

    Science.gov (United States)

    Kang, P. K.; Lei, Q.; Lee, S.; Dentz, M.; Juanes, R.

    2017-12-01

    Fluid flow and transport in fractured rock controls many natural and engineered processes in the subsurface. However, characterizing flow and transport through fractured media is challenging due to the high uncertainty and large heterogeneity associated with fractured rock properties. In addition to these "static" challenges, geologic fractures are always under significant overburden stress, and changes in the stress state can lead to changes in the fracture's ability to conduct fluids. While confining stress has been shown to impact fluid flow through fractures in a fundamental way, the impact of confining stress on transportthrough fractured rock remains poorly understood. The link between anomalous (non-Fickian) transport and confining stress has been shown, only recently, at the level of a single rough fracture [1]. Here, we investigate the impact of geologic (tectonic) stress on flow and tracer transport through natural fracture networks. We model geomechanical effects in 2D fractured rock by means of a finite-discrete element method (FEMDEM) [2], which can capture the deformation of matrix blocks, reactivation of pre-existing fractures, and propagation of new cracks, upon changes in the stress field. We apply the model to a fracture network extracted from the geological map of an actual rock outcrop to obtain the aperture field at different stress conditions. We then simulate fluid flow and particle transport through the stressed fracture networks. We observe that anomalous transport emerges in response to confining stress on the fracture network, and show that the stress state is a powerful determinant of transport behavior: (1) An anisotropic stress state induces preferential flow paths through shear dilation; (2) An increase in geologic stress increases aperture heterogeneity that induces late-time tailing of particle breakthrough curves. Finally, we develop an effective transport model that captures the anomalous transport through the stressed fracture

  9. Spartan Release Engagement Mechanism (REM) stress and fracture analysis

    Science.gov (United States)

    Marlowe, D. S.; West, E. J.

    1984-01-01

    The revised stress and fracture analysis of the Spartan REM hardware for current load conditions and mass properties is presented. The stress analysis was performed using a NASTRAN math model of the Spartan REM adapter, base, and payload. Appendix A contains the material properties, loads, and stress analysis of the hardware. The computer output and model description are in Appendix B. Factors of safety used in the stress analysis were 1.4 on tested items and 2.0 on all other items. Fracture analysis of the items considered fracture critical was accomplished using the MSFC Crack Growth Analysis code. Loads and stresses were obtaind from the stress analysis. The fracture analysis notes are located in Appendix A and the computer output in Appendix B. All items analyzed met design and fracture criteria.

  10. Stress fractures: pathophysiology, clinical presentation, imaging features, and treatment options.

    Science.gov (United States)

    Matcuk, George R; Mahanty, Scott R; Skalski, Matthew R; Patel, Dakshesh B; White, Eric A; Gottsegen, Christopher J

    2016-08-01

    Stress fracture, in its most inclusive description, includes both fatigue and insufficiency fracture. Fatigue fractures, sometimes equated with the term "stress fractures," are most common in runners and other athletes and typically occur in the lower extremities. These fractures are the result of abnormal, cyclical loading on normal bone leading to local cortical resorption and fracture. Insufficiency fractures are common in elderly populations, secondary to osteoporosis, and are typically located in and around the pelvis. They are a result of normal or traumatic loading on abnormal bone. Subchondral insufficiency fractures of the hip or knee may cause acute pain that may present in the emergency setting. Medial tibial stress syndrome is a type of stress injury of the tibia related to activity and is a clinical syndrome encompassing a range of injuries from stress edema to frank-displaced fracture. Atypical subtrochanteric femoral fracture associated with long-term bisphosphonate therapy is also a recently discovered entity that needs early recognition to prevent progression to a complete fracture. Imaging recommendations for evaluation of stress fractures include initial plain radiographs followed, if necessary, by magnetic resonance imaging (MRI), which is preferred over computed tomography (CT) and bone scintigraphy. Radiographs are the first-line modality and may reveal linear sclerosis and periosteal reaction prior to the development of a frank fracture. MRI is highly sensitive with findings ranging from periosteal edema to bone marrow and intracortical signal abnormality. Additionally, a brief description of relevant clinical management of stress fractures is included.

  11. Lower thoracic rib stress fractures in baseball pitchers.

    Science.gov (United States)

    Gerrie, Brayden J; Harris, Joshua D; Lintner, David M; McCulloch, Patrick C

    2016-01-01

    Stress fractures of the first rib on the dominant throwing side are well-described in baseball pitchers; however, lower thoracic rib fractures are not commonly recognized. While common in other sports such as rowing, there is scant literature on these injuries in baseball. Intercostal muscle strains are commonly diagnosed in baseball pitchers and have a nearly identical presentation but also a highly variable healing time. The diagnosis of a rib stress fracture can predict a more protracted recovery. This case series presents two collegiate baseball pitchers on one team during the same season who were originally diagnosed with intercostal muscle strains, which following magnetic resonance imaging (MRI) were found to have actually sustained lower thoracic rib stress fractures. The first sustained a stress fracture of the posterior aspect of the right 8th rib on the dominant arm side, while the second presented with a left-sided 10th rib stress fracture on the nondominant arm side. In both cases, MRI was used to visualize the fractures as plain radiographs are insensitive and commonly negative early in patient presentation. Patients were treated with activity modification, and symptomatic management for 4-6 weeks with a graduated return to throwing and competition by 8-10 weeks. The repetitive high stresses incurred by pitching may cause either dominant or nondominant rib stress fractures and this should be included in the differential diagnosis of thoracic injuries in throwers. It is especially important that athletic trainers and team physicians consider this diagnosis, as rib fractures may have a protracted course and delayed return to play. Additionally, using the appropriate imaging techniques to establish an accurate diagnosis can help inform return-to-play decisions, which have important practical applications in baseball, such as roster management and eligibility.

  12. Stress fractures of the femora in soldiers

    International Nuclear Information System (INIS)

    Meurman, K.O.A.; Somer, K.; Lamminen, A.

    1981-01-01

    Amongst 936 stress fractures found in soldiers, there were 58 in the femora (6%); of these 31 were in the neck and 27 in the shaft. Two were bilateral, and two patients had other stress fractures. Three displacements were found in the necks. In the shaft, 20 fractures were proximal, four were in the middle third and three in the distal third. In the latter group, it is necessary to differentiate from a sarcoma. CT is a new aid in this respect. Sport in highly motivated individuals appears to contribute particularly to fractures of the shaft. The symptoms from these fractures are relatively mild. (orig.) [de

  13. Stress fractures of the femora in soldiers

    Energy Technology Data Exchange (ETDEWEB)

    Meurman, K O.A.; Somer, K; Lamminen, A

    1981-05-01

    Amongst 936 stress fractures found in soldiers, there were 58 in the femora (6%); of these 31 were in the neck and 27 in the shaft. Two were bilateral, and two patients had other stress fractures. Three displacements were found in the necks. In the shaft, 20 fractures were proximal, four were in the middle third and three in the distal third. In the latter group, it is necessary to differentiate from a sarcoma. CT is a new aid in this respect. Sport in highly motivated individuals appears to contribute particularly to fractures of the shaft. The symptoms from these fractures are relatively mild.

  14. Influence of fracture extension on in-situ stress in tight reservoir

    Science.gov (United States)

    Zhang, Yongping; Wei, Xu; Zhang, Ye; Xing, Libo; Xu, Jianjun

    2018-01-01

    Currently, hydraulic fracturing is an important way to develop low permeability reservoirs. The fractures produced during the fracturing process are the main influencing factors of changing in-situ stress. In this paper, the influence of fracture extension on in-situ stress is studied by establishing a mathematical model to describe the relationship between fracture length and in-situ stress. The results show that the growth rate gradually decreases after the fracture reaches a certain length with the increase of fracturing time; the continuous extension of the fracture is the main factor to change the in-situ stress. In order to reduce the impact on the subsequent fracture extension due to the changing of in-situ stress, controlling fracturing time and fracture length without affecting the stimulated reservoir effect is an important way. The results presented in this study can effectively reduce the impact of changing of in-situ stress on subsequent fracturing construction.

  15. Correlation Between Fracture Network Properties and Stress Variability in Geological Media

    Science.gov (United States)

    Lei, Qinghua; Gao, Ke

    2018-05-01

    We quantitatively investigate the stress variability in fractured geological media under tectonic stresses. The fracture systems studied include synthetic fracture networks following power law length scaling and natural fracture patterns based on outcrop mapping. The stress field is derived from a finite-discrete element model, and its variability is analyzed using a set of mathematical formulations that honor the tensorial nature of stress data. We show that local stress perturbation, quantified by the Euclidean distance of a local stress tensor to the mean stress tensor, has a positive, linear correlation with local fracture intensity, defined as the total fracture length per unit area within a local sampling window. We also evaluate the stress dispersion of the entire stress field using the effective variance, that is, a scalar-valued measure of the overall stress variability. The results show that a well-connected fracture system under a critically stressed state exhibits strong local and global stress variabilities.

  16. One-stage metatarsal lengthening by allograft interposition: a novel approach for congenital brachymetatarsia.

    Science.gov (United States)

    Giannini, Sandro; Faldini, Cesare; Pagkrati, Stavroula; Miscione, Maria Teresa; Luciani, Deianira

    2010-07-01

    Congenital brachymetatarsia, a shortened metatarsal bone, can be corrected surgically by callus distraction or one-stage lengthening using bone graft. We asked whether one-stage metatarsal lengthening using metatarsal homologous bone graft could improve forefoot function, lead to metatarsal healing, restore metatarsal parabola, and improve cosmetic appearance. We retrospectively reviewed 29 patients (41 feet) in whom we lengthened 50 metatarsals. Surgery consisted of a transverse proximal osteotomy of the metatarsal shaft and interposition of a metatarsal homologous bone graft (average, 13 mm long) fixed with an intramedullary Kirschner wire. Minimum followup was 3 years (mean, 5 years; range, 3-11 years). Bone union was achieved in all cases. The mean preoperative American Orthopaedic Foot and Ankle Society score was 37 points (range, 28-53 points) and the mean postoperative score was 88 points (range, 74-96 points), with an average improvement of 51 points. Radiographically, the mean gain in length was 13 mm (range, 10-15 mm), and the mean percentage increase was 23%. One-stage metatarsal lengthening using interposition of metatarsal homologous bone graft to correct congenital brachymetatarsia has low morbidity for the patient, limited complications, short recovery times, and restores forefoot anatomy. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

  17. Connection between tectonic stresses and well fracturing data

    Energy Technology Data Exchange (ETDEWEB)

    Scheidegger, A E [Imperial Oil Res. Lab., Calgary, CA

    1961-01-01

    Theoretical considerations of hydraulic well fracturing normally utilize a model in which the borehole is assumed to be a cylinder of infinite length. This leads to treatment of the induced stress state in two dimensions. The two-dimensional model is obviously an oversimplification. Therefore, a three-dimensional model is proposed in which the well pressure is assumed to be equivalent to a spherical pressure center. The bottom hole pressure during fracturing is determined by 4 variables; i.e., the 3 principal geological stresses and the rock strength. The response to fracturing is determined primarily by the prevailing stress state and to a lesser degree by the rock strength. The fracture condition is formulated and the model is used in the calculation of geological stresses from well data.

  18. Trochanteric Stress Fracture in a Female Window Cleaner

    OpenAIRE

    Lee, Bong-Jin; Song, Jyewon

    2016-01-01

    Stress fractures may occur at various sites in the femur including the head, neck, shaft, supracondylar and condylar regions. To the best of our knowledge, stress fracture occurring in the trochanteric region has not been previously reported. We report here a case of trochanteric stress fracture in a 53-year-old female window cleaner treated with hip nailing without adverse consequences. Careful consideration of this entity is needed when evaluating patients who have repetitive jumping up and...

  19. Tensile Properties of the Deep Transverse Metatarsal Ligament in Hallux Valgus

    Science.gov (United States)

    Abdalbary, Sahar Ahmed; Elshaarawy, Ehab A.A.; Khalid, Bahaa E.A.

    2016-01-01

    Abstract The deep transverse metatarsal ligament (DTML) connects the neighboring 2 metatarsal heads and is one of the stabilizers connecting the lateral sesamoid and second metatarsal head. In this study, we aimed to determine the tensile properties of the DTML in normal specimens and to compare these results with hallux valgus specimens. We hypothesized that the tensile properties of the DTML would be different between the 2 groups of specimens. The DTML in the first interspace was dissected from 12 fresh frozen human cadaveric specimens. Six cadavers had bilateral hallux valgus and the other 6 cadavers had normal feet. The initial length (L0) and cross-sectional area (A0) of the DTML were measured using a digital caliper, and tensile tests with load failure were performed using a material testing machine. There were significant between-groups differences in the initial length (L0) P = 0.009 and cross-sectional area (A0) of the DTML P = 0.007. There were also significant between-groups differences for maximum force (N) P = 0.004, maximum distance (mm) P = 0.005, maximum stress (N/mm2) P = 0.003, and maximum strain (%) P = 0.006. The DTML is an anatomical structure for which the tensile properties differ in hallux valgus. PMID:26937914

  20. 3-D description of fracture surfaces and stress-sensitivity analysis for naturally fractured reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S.Q.; Jioa, D.; Meng, Y.F.; Fan, Y.

    1997-08-01

    Three kinds of reservoir cores (limestone, sandstone, and shale with natural fractures) were used to study the effect of morphology of fracture surfaces on stress sensitivity. The cores, obtained from the reservoirs with depths of 2170 to 2300 m, have fractures which are mated on a large scale, but unmated on a fine scale. A specially designed photoelectric scanner with a computer was used to describe the topography of the fracture surfaces. Then, theoretical analysis of the fracture closure was carried out based on the fracture topography generated. The scanning results show that the asperity has almost normal distributions for all three types of samples. For the tested samples, the fracture closure predicted by the elastic-contact theory is different from the laboratory measurements because plastic deformation of the aspirates plays an important role under the testing range of normal stresses. In this work, the traditionally used elastic-contact theory has been modified to better predict the stress sensitivity of reservoir fractures. Analysis shows that the standard deviation of the probability density function of asperity distribution has a great effect on the fracture closure rate.

  1. Radioisotopic and Radiological Evaluation in Patient with Stress Fracture

    International Nuclear Information System (INIS)

    Ko, Kwang Seop; Kim, Jai Young; Kang, Sung Koo; Kim, So Yon; Lee, Gwon Jun

    1987-01-01

    The stress fracture is a disease caused by and abnormal stress to the normal bone with constant, repeated pull. Early detection of stress fracture plays an important role in treatment and prevention of its complication. Bone scintigraphy was performed to evaluate 18 patients with stress fracture of the lower extremities from May, 1985 to April, 1987, in the Department of Internal Medicine of National Police Hospital. The results were as follows: 1) Seventeen of the 18 cases showed positive bone scans at the initial study performed from 1 week to 5 months after the onset of symptom. 2) Ten of the 18 patients had findings of stress fracture at the initial X-ray film. Two out of 8 negative case revealed positive findings in the follow-up studies. 3) The bone scans in the 2 cases taken 5 months after the onset of symptom; the one showed only slightly increased radio uptake, the other showed no abnormal findings. In conclusion, bone scanning is a more sensitive indicator of early stress fracture than radiologic study, The healing phase is characterized by a gradual decline in radioactivity at the fracture site in concordance with subsidence of symptom.

  2. Case report: bilateral ischial stress fractures in an elite tennis player

    International Nuclear Information System (INIS)

    Clarke, A.W.; Connell, D.A.

    2009-01-01

    A case report of bilateral ischial stress fractures in an elite tennis player initially mimicking hamstring pathology is described. This is an unusual site of stress fracture. Typical sites of stress fracture are well documented; however, awareness of less common sites of stress-related bone injury can aid early diagnosis and treatment before overt fracture occurs. (orig.)

  3. Case report: bilateral ischial stress fractures in an elite tennis player

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, A.W.; Connell, D.A. [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, London, Middlesex (United Kingdom)

    2009-07-15

    A case report of bilateral ischial stress fractures in an elite tennis player initially mimicking hamstring pathology is described. This is an unusual site of stress fracture. Typical sites of stress fracture are well documented; however, awareness of less common sites of stress-related bone injury can aid early diagnosis and treatment before overt fracture occurs. (orig.)

  4. Lengthening of the shortened first metatarsal after Wilson's osteotomy for hallux valgus.

    Science.gov (United States)

    Singh, D; Dudkiewicz, I

    2009-12-01

    Metatarsalgia is a recognised complication following iatrogenic shortening of the first metatarsal in the management of hallux valgus. The traditional surgical treatment is by shortening osteotomies of the lesser metatarsals. We describe the results of lengthening of iatrogenic first brachymetatarsia in 16 females. A Scarf-type osteotomy was used in the first four cases and a step-cut of equal thicknesses along the axis of the first metatarsal was performed in the others. The mean follow-up was 21 months (19 to 26). Relief of metatarsalgia was obtained in the six patients in whom 10 mm of lengthening had been achieved, compared to only 50% relief in those where less than 8 mm of lengthening had been gained. One-stage step-cut lengthening osteotomy of the first metatarsal may be preferable to shortening osteotomies of the lesser metatarsals in the treatment of metatarsalgia following surgical shortening of the first metatarsal.

  5. Postpartum Sacral Stress Fracture: An Atypical Case Report

    Directory of Open Access Journals (Sweden)

    Andrea Speziali

    2015-01-01

    Full Text Available Sacral stress fractures are common in elderly people. However, sacral stress fracture should be always screened in the differential diagnoses of low back pain during the postpartum period. We present a case of sacral fracture in a thirty-six-year-old woman with low back pain and severe right buttock pain two days after cesarean section delivery of a 3.9 Kg baby. The diagnosis was confirmed by MRI and CT scan, while X-ray was unable to detect the fracture. Contribution of mechanical factors during the cesarean section is not a reasonable cause of sacral fracture. Pregnancy and lactation could be risk factors for sacral stress fracture even in atraumatic delivery such as cesarean section. Our patient had no risk factors for osteoporosis except for pregnancy and lactation. Transient or focal osteoporosis is challenging to assess and it cannot be ruled out even if serum test and mineral density are within the normal range.

  6. Tibial stress fractures in racing Standardbreds: 13 cases (1989-1993)

    International Nuclear Information System (INIS)

    Ruggles, A.J.; Moore, R.M.; Bertone, A.L.; Schneider, R.K.; Bailey, M.Q.

    1996-01-01

    To determine clinical signs, radiographic and scintigraphic findings, and performance outcome of racing Standardbreds with tibial stress fractures. Retrospective case series. 13 racing Standardbreds with tibial stress fractures. Information concerning clinical signs, diagnostic evaluation, and recommendations was obtained by review of the medical records. Performance information before and after diagnosis of the fracture was collected from racing records, and follow-up information was obtained from the owners or trainers by use of a telephone questionnaire. Horses with tibial stress fractures were moderately lame, and diagnosis was made by nuclear scintigraphy and radiography. Fractures were more likely to occur in 2-year-old horses than in older horses. The fracture location was unique for Standardbreds; 11 of 13 developed stress fractures in the mid-diaphysis of the tibia, whereas fractures in Thoroughbreds are usually in the proximal caudal or caudolateral cortex. Fractures occurred in young horses that had raced or were in advanced race training. All horses were treated with rest alone, and 10 of 13 horses raced after injury. The horses that raced after injury were able to return to a level of performance that was equal to or better than the level raced before injury. 8 of 10 horses established a lifetime-best winning time after injury. Tibial stress fractures are a cause of lameness in young racing Standardbreds. Diagnosis is aided by nuclear scintigraphy. The prognosis for return to previous level of performance after a tibial stress fracture is good

  7. Fatigue stress fractures of the sacrum: diagnosis with MR imaging

    International Nuclear Information System (INIS)

    Ahovuo, J.A.; Vusuri, T.

    2004-01-01

    The aim of this study was to describe the MRI findings and clinical observations in a fatigue stress fracture of the sacrum. In this retrospective study, 380 conscripts (53 women, 327 men; age range 18-29 years, mean age 20.7 years) who suffered from stress-related hip pain were studied with MRI of the pelvis. The findings of MRI were evaluated with regard to stress fracture of the sacrum. Thirty-one (8%) patients had MRI changes in signal intensity of the cranial part of the sacrum, extending to the first and second sacral foramina. The MRI changes in signal intensity were intermediate on T1-weighted images, and high on short tau inversion recovery or T2-weighted fat-suppressed images. A linear signal void fracture line was also seen. Multiple stress injuries to the pelvic bones were also seen in 7 of 31 (23%) patients. Five patients (16%) had bilateral sacral stress fracture. Fatigue sacral stress fractures appeared more commonly in women than in men (p<0.001). During recovery time 20 of the 31 patients underwent control MRI, and fatty marrow conversion was seen in 8 (40%) cases as high signal intensity on T1-weighted images, which disappeared 5-6 months after the onset of symptoms. Fatigue sacral stress fractures are associated with stress-related hip pain. These fractures were more common in women than in men. Other stress injuries of the pelvis may be seen simultaneously with sacral stress fractures. Signal intensity of the sacrum was normal after 5-6 months

  8. Novo Parafuso (Acutrak® No tratamento cirúrgico de jogadores de futebol de elite com fraturas do quinto metatarso New screw (Acutrak® in the surgical treatment of elite football players with fifth metatarsal

    Directory of Open Access Journals (Sweden)

    Hayati Ozturk

    2009-01-01

    Full Text Available OBJETIVO: Há uma variabilidade considerável na literatura no que tange ao tratamento ideal de fraturas do quinto metatarso. O objetivo deste estudo é apresentar os resultados da fixação cirúrgica de fraturas do quinto metatarso usando o parafuso Acutrak® em jogadores de futebol de elite. MATERIAL E MÉTODOS: Três casos de fratura do quinto metatarso em jogadores de futebol de elite são apresentados. A média de idade dos pacientes era de 24 anos (18-26 anos. Tratamos as três fraturas do quinto metatarso em jogadores de futebol de elite. Os casos em nosso estudo consistiam de uma fratura diafisiária do quinto metatarso e duas fraturas de Jones. As fraturas ocorreram durante a participação nos jogos. Aplicamos fixação interna utilizando um parafuso Acutrak® percutâneo sob anestesia local com o auxílio de um fluoroscópio. Os pacientes foram clinica e radiograficamente avaliados. RESULTADOS: O restabelecimento clínico foi obtido em 10 semanas após a cirurgia. A consolidação radiográfica ocorreu em 8 semanas de pós-operatório, sendo que os pacientes retornaram a seus níveis prévios de atividade em 11 semanas de pós-operatório. Não foi relatada nenhuma complicação pósoperatória. Não se observou nenhuma irritação de pele devido à ausência de cabeça do parafuso Acutrak®. CONCLUSÃO: Os resultados sugerem que Acutrak® pode ser usado em jogadores de futebol com fraturas do quinto metatarso. Apesar de fatores como facilidade de implante, o custo e a resistência a inclinação também devem ser considerados.OBJECTIVE: There is considerable variability in the literature concerning the optimal treatment of fifth metatarsal fracture. The purpose of this study is to report the outcome of surgical fixation of fifth metatarsal fractures using Acutrak® screw in elite football players. MATERIAL AND METHOD: Three cases of fifth metatarsal fracture in elite football players. The mean age was 24 years old (18-26 years. We

  9. Spontaneous stress fractures of the femoral neck

    International Nuclear Information System (INIS)

    Dorne, H.L.; Lander, P.H.

    1985-01-01

    The diagnosis of spontaneous stress fractures of the femoral neck, a form of insufficiency stress fracture, can be missed easily. Patients present with unremitting hip pain without a history of significant trauma or unusual increase in daily activity. The initial radiographic features include osteoporosis, minor alterations of trabecular alignment, minimal extracortical or endosteal reaction, and lucent fracture lines. Initial scintigraphic examinations performed in three of four patients showed focal increased radionuclide uptake in two and no focal abnormality in one. Emphasis is placed on the paucity of early findings. Evaluation of patients with persistent hip pain requires a high degree of clinical suspicion and close follow-up; the sequelae of undetected spontaneous fractures are subcapital fracture with displacement, angular deformity, and a vascular necrosis of the femoral head

  10. Upper extremity and rib stress fractures in a child

    International Nuclear Information System (INIS)

    Moon, B.S.; Price, C.T.; Campbell, J.B.

    1998-01-01

    Stress fractures in children are rare compared with the incidence in [ults. This report describes an 11-year-old girl with stress fractures of the acromion, clavicle, and first rib on the left and contralateral fractures of the first and second ribs. It was eventually discovered that these fractures were caused by a nervous tic consisting of repetitive, vigorous shrugging and translation of the shoulders. (orig.)

  11. Polyaxial stress-dependent permeability of a three-dimensional fractured rock layer

    Science.gov (United States)

    Lei, Qinghua; Wang, Xiaoguang; Xiang, Jiansheng; Latham, John-Paul

    2017-12-01

    A study about the influence of polyaxial (true-triaxial) stresses on the permeability of a three-dimensional (3D) fractured rock layer is presented. The 3D fracture system is constructed by extruding a two-dimensional (2D) outcrop pattern of a limestone bed that exhibits a ladder structure consisting of a "through-going" joint set abutted by later-stage short fractures. Geomechanical behaviour of the 3D fractured rock in response to in-situ stresses is modelled by the finite-discrete element method, which can capture the deformation of matrix blocks, variation of stress fields, reactivation of pre-existing rough fractures and propagation of new cracks. A series of numerical simulations is designed to load the fractured rock using various polyaxial in-situ stresses and the stress-dependent flow properties are further calculated. The fractured layer tends to exhibit stronger flow localisation and higher equivalent permeability as the far-field stress ratio is increased and the stress field is rotated such that fractures are preferentially oriented for shearing. The shear dilation of pre-existing fractures has dominant effects on flow localisation in the system, while the propagation of new fractures has minor impacts. The role of the overburden stress suggests that the conventional 2D analysis that neglects the effect of the out-of-plane stress (perpendicular to the bedding interface) may provide indicative approximations but not fully capture the polyaxial stress-dependent fracture network behaviour. The results of this study have important implications for understanding the heterogeneous flow of geological fluids (e.g. groundwater, petroleum) in subsurface and upscaling permeability for large-scale assessments.

  12. Sacral Stress Fracture in an Amateur Badminton Player

    Directory of Open Access Journals (Sweden)

    Yusuke Yuasa

    2017-01-01

    Full Text Available Sacral stress fractures are rare among athletes but have been reported most frequently in long distance runners. We report herein the first case of a sacral stress fracture in an amateur badminton player. A 16-year-old, left-handed adolescent girl, who had just started to play badminton 3 months previously, complained of acute left buttock pain when she received a shuttlecock. Magnetic resonance imaging revealed a linear lesion of the left sacrum with low signal intensity on T1- and high signal intensity on T2-weighted images, which was consistent with a stress fracture. Conservative treatment with rest relieved her symptoms. Her fracture was considered to have occurred due to repetition of an exercise that caused excessive vertical power.

  13. Stress fractures of ankle and wrist in childhood: nature and frequency

    International Nuclear Information System (INIS)

    Oestreich, Alan E.; Bhojwani, Nicholas

    2010-01-01

    Stress fractures of many etiologies are found not infrequently in various tarsal bones but are less commonly recognized in carpal bones. To assess the distribution of tarsal and carpal stress fractures. During the last three decades, the senior author collected locations of tarsal and carpal bone stress fracture callus seen on plain radiographs. 527 children with tarsal and carpal stress fractures were identified (88 children had multiple bones involved). The totals were: calcaneus 244, cuboid 188, talus 121, navicular 24, cuneiforms 23, capitate 18, lunate 1, and scaphoid 1. Stress fractures were more frequently seen once we became aware each particular bone could be involved. Tarsal and carpal stress fractures in children are not rare. Careful perusal of these bones is urged in all susceptible children with limping or wrist pain. (orig.)

  14. Stress fractures of ankle and wrist in childhood: nature and frequency

    Energy Technology Data Exchange (ETDEWEB)

    Oestreich, Alan E. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Bhojwani, Nicholas [University of Cincinnati College of Medicine, Cincinnati, OH (United States)

    2010-08-15

    Stress fractures of many etiologies are found not infrequently in various tarsal bones but are less commonly recognized in carpal bones. To assess the distribution of tarsal and carpal stress fractures. During the last three decades, the senior author collected locations of tarsal and carpal bone stress fracture callus seen on plain radiographs. 527 children with tarsal and carpal stress fractures were identified (88 children had multiple bones involved). The totals were: calcaneus 244, cuboid 188, talus 121, navicular 24, cuneiforms 23, capitate 18, lunate 1, and scaphoid 1. Stress fractures were more frequently seen once we became aware each particular bone could be involved. Tarsal and carpal stress fractures in children are not rare. Careful perusal of these bones is urged in all susceptible children with limping or wrist pain. (orig.)

  15. Stress fractures: definition, diagnosis and treatment ?

    OpenAIRE

    Astur, Diego Costa; Zanatta, Fernando; Arliani, Gustavo Gon?alves; Moraes, Eduardo Ramalho; Pochini, Alberto de Castro; Ejnisman, Benno

    2015-01-01

    ABSTRACT Stress fractures were first described in Prussian soldiers by Breithaupt in 1855. They occur as the result of repeatedly making the same movement in a specific region, which can lead to fatigue and imbalance between osteoblast and osteoclast activity, thus favoring bone breakage. In addition, when a particular region of the body is used in the wrong way, a stress fracture can occur even without the occurrence of an excessive number of functional cycles. The objective of this study wa...

  16. Influence of microporosity on fracture stress of pyrocarbon coatings

    International Nuclear Information System (INIS)

    Krautwasser, P.; Nickel, H.; Taueber, K.

    1975-01-01

    In this paper recent investigations on fracture behaviour of integral PyC-coatings are presented. The fracture stresses of propene, acetylene, and methane-derived pyrocarbons are measured as a function of deposition temperature and deposition rate. The measured fracture stresses are interpreted in terms of microporosity values determined by X-ray small angle scattering (SAXS). It can be shown that the fracture stress is correlated unambigously with the concentration of micropores in the range of about 50 to 500A diameter. TEM inspection of the investigated materials revealed a component of disordered, tangled fibres with a high microporosity in agreement with SAXS results. This component increases with temperature in the range of 1250 to 1400 at the expense of of a high-density component. As a result, the coatings deposited in this temperature range show decreasing fracture stress with increasing amount of the porous glass wool like component. PyC coatings with a good irradiation behaviour had an initial pore size distribution typical for a relatively high content of tangled material. The assumption, that a relatively high amount of the disordered material is fafourable for a good behaviour i.e. integrity of coating up to high neutron doses, was confirmed besides other investigations by the relative low preirradiation fracture stresses of the well behaving coatings. This means, the integrity of pyrocarbon coatings after irradiation is favoured not so much by a high preirradiation fracture stress, but by the enhanced dimensional stability of the disordered porous material. In addition to this, the increase of the relatively low fractures stress due to the measured irradiation induced reduction of pores in the size range of 200 to 1000A diameter is in favour of coating integrity

  17. Bilateral femoral supracondylar stress fractures in a cross country runner.

    Science.gov (United States)

    Ross, Kate; Fahey, Mark

    2008-08-01

    Several high-risk factors lead to stress fractures. They include excessive training in athletes leading to overuse injuries, nutritional deficiencies, and endocrine disorders. While stress fractures are common, bilateral stress fractures are rarely seen. Few cases have been reported of bilateral femoral stress fractures in young athletes. This article presents a case of a 14-year-old cross country runner with a bilateral femoral supracondylar stress fracture. He presented with bilateral supracondylar stress fractures from running. The patient followed a strict vegan diet, but his parents stated that, to their knowledge, he was getting adequate protein and calcium. Treatment consisted of decreased activity to pain-free levels with acetaminophen for pain. Low-impact conditioning such as swimming and bicycling was allowed. Hamstring and quadricep stretching was suggested. Nutritional consultation was obtained to ensure appropriate nutrition on a vegan diet. At 1-month follow-up, he was pain free and allowed to proceed with a gradual return to running activities. In this case, the onset of a new workout routine was intolerable for this patient's low bone density, causing insufficiency fractures. Appropriate vegan diets were not associated with stress fracture in our literature review. He may have had an inadequate diet prior to this injury. As in this case, full recovery can be made after this rest period, and the patient may return to his or her original activity safely. In young athletes, diet and nutrition must be kept in mind.

  18. kISMET: Stress and fracture characterization in a deep mine

    Science.gov (United States)

    Oldenburg, C. M.; Dobson, P. F.; Daley, T. M.; Birkholzer, J. T.; Cook, P. J.; Ajo Franklin, J. B.; Rutqvist, J.; Siler, D.; Kneafsey, T. J.; Nakagawa, S.; Wu, Y.; Guglielmi, Y.; Ulrich, C.; Marchesini, P.; Wang, H. F.; Haimson, B. C.; Sone, H.; Vigilante, P.; Roggenthen, W.; Doe, T.; Lee, M.; Mattson, E.; Huang, H.; Johnson, T. C.; Morris, J.; White, J. A.; Johnson, P. A.; Coblentz, D. D.; Heise, J.

    2016-12-01

    We are developing a community facility called kISMET (permeability (k) and Induced Seismicity Management for Energy Technologies) at the Sanford Underground Research Facility (SURF) in Lead, SD. The purpose of kISMET is to investigate stress and the effects of rock fabric on hydraulic fracturing. Although findings from kISMET may have broad applications that inform stress and fracturing in anisotropic rock, results will be most applicable to improving control of hydraulic fracturing for enhanced geothermal systems (EGS) in crystalline rock. At the kISMET site on the 4850 ft (1480 m depth) level of SURF, we have drilled and cored an array of nearly vertical boreholes in Precambrian phyllite. The array consists of four 50-m deep monitoring boreholes surrounding one 100-m deep borehole forming a 6 m-wide five-spot pattern at a depth of 1530 m. Previous investigations of the stress field at SURF suggest that the principal stress s1 is nearly vertical. By aligning the kISMET boreholes approximately with σ1, fractures created in the center borehole should in theory be perpendicular to σ3, the least principal horizontal stress. But the phyllite at kISMET has a strong fabric (foliation) that could influence fracturing. Stress measurements and stimulation using hydraulic fracturing will be carried out in the center borehole using a straddle packer and high-pressure pump. We will use an impression packer and image logs after stress testing and stimulation to determine fracture orientation and extent at the center borehole. In order to study the control of stress, rock fabric, and stimulation approach on size, aperture, and orientation of hydraulic fractures, we will carefully monitor the stress measurements and stimulation. For example, we will use continuous active source seismic (CASSM) in two of the monitoring boreholes to measure changes in seismic-wave velocity as water fills the fracture. Second, near real-time electrical resistance tomography (ERT) will be used in

  19. Stress generation and hierarchical fracturing in reactive systems

    Science.gov (United States)

    Jamtveit, B.; Iyer, K.; Royne, A.; Malthe-Sorenssen, A.; Mathiesen, J.; Feder, J.

    2007-12-01

    Hierarchical fracture patterns are the result of a slowly driven fracturing process that successively divides the rocks into smaller domains. In quasi-2D systems, such fracture patterns are characterized by four sided domains, and T-junctions where new fractures stop at right angles to pre-existing fractures. We describe fracturing of mm to dm thick enstatite layers in a dunite matrix from the Leka ophiolite complex in Norway. The fracturing process is driven by expansion of the dunite matrix during serpentinization. The cumulative distributions of fracture lengths show a scaling behavior that lies between a log - normal and power law (fractal) distribution. This is consistent with a simple fragmentation model in which domains are divided according to a 'top hat' distribution of new fracture positions within unfractured domains. Reaction-assisted hierarchical fracturing is also likely to be responsible for other (3-D) structures commonly observed in serpentinized ultramafic rocks, including the mesh-textures observed in individual olivine grains, and the high abundance of rectangular domains at a wide range of scales. Spectacular examples of 3-D hierarchical fracture patterns also form during the weathering of basaltic intrusions (dolerites). Incipient chemical weathering of dolerites in the Karoo Basin in South Africa occurs around water- filled fractures, originally produced by thermal contraction or by externally imposed stresses. This chemical weathering causes local expansion of the rock matrix and generates elastic stresses. On a mm to cm scale, these stresses lead to mechanical layer-by-layer spalling, producing the characteristic spheroidal weathering patterns. However, our field observations and computer simulations demonstrate that in confined environments, the spalling process alone is unable to relieve the elastic stresses. In such cases, chemical weathering drives a much larger scale hierarchical fracturing process in which fresh dolerite undergoes a

  20. First Metatarsal Head and Medial Eminence Widths with and Without Hallux Valgus.

    Science.gov (United States)

    Lenz, Robin C; Nagesh, Darshan; Park, Hannah K; Grady, John

    2016-09-02

    Resection of the medial eminence in hallux valgus surgery is common. True hypertrophy of the medial eminence in hallux valgus is debated. No studies have compared metatarsal head width in patients with hallux valgus and control patients. We reviewed 43 radiographs with hallux valgus and 27 without hallux valgus. We measured medial eminence width, first metatarsal head width, and first metatarsal shaft width in patients with and without radiographic hallux valgus. Medial eminence width was 1.12 mm larger in patients with hallux valgus (P hallux valgus (P hallux valgus. However, frontal plane rotation of the first metatarsal likely accounts for this difference.

  1. Estimation of the controlling stress in creep fracture

    International Nuclear Information System (INIS)

    Henderson, J.; Ferguson, F.R.

    1975-01-01

    The implementation of correct criterion in creep design, has been shown to be of fundamental significance in the assessment of component life. The present report considers the problem of the means whereby the criterion may be derived for a particular metal without the availability of sophisticated complex-stress testing equipment and procedures such as the combined tension and torsion tests on thin walled tubular specimens employed in the earlier fundamental researches on the subject. By investigating a wide spectrum of engineering metals it was established that for homogeneous stress conditions two criteria appeared to be sufficient to cover all the metals studied for complex-stress creep fracture, either the maximum principal stress or the octahedral shear stress criterion. Further, it was found that those metals which developed random and continuous cracking during creep were controlled with respect to fracture time by the maximum principal stress, while metals which showed virtually no cracking were governed by the octahedral shear stress or second order invariant. The physical nature of the final fracture (transcrystalline or inter-crystalline), contrary to considerable current concepts, was found to be unrelated to which criterion was operative. Having reduced the possible fracture criteria to two, it only remained to develop a simple test method exploiting this finding to achieve the precise identification for a particular metal. Seven metals including aluminium, copper, titanium, cast iron and three steels have been investigated in the present report at temperatures where creep conditions are operative. The results have shown that the method leads to sufficiently accurate prediction of the complex stress creep fracture criterion for the metals studied

  2. Ultrasound-Diagnosed Tibia Stress Fracture: A Case Report.

    Science.gov (United States)

    Amoako, Adae; Abid, Ayesha; Shadiack, Anthony; Monaco, Robert

    2017-01-01

    Stress fractures are a frequent cause of lower extremity pain in athletes, and especially in runners. Plain imaging has a low sensitivity. Magnetic resonance imaging (MRI) or bone scan scintigraphy is the criterion standard, but expensive. We present the case of a young female distance runner with left shin pain. Plain radiography was unremarkable. Ultrasound showed focal hyperechoic elevation of the periosteum with irregularity over the distal tibia and increased flow on Doppler. These findings were consistent with a distal tibia stress fracture and confirmed by MRI. Examination of our case will highlight the utility of considering an ultrasound for diagnosis of tibial stress fracture.

  3. Ultrasound-Diagnosed Tibia Stress Fracture: A Case Report

    Directory of Open Access Journals (Sweden)

    Adae Amoako

    2017-04-01

    Full Text Available Stress fractures are a frequent cause of lower extremity pain in athletes, and especially in runners. Plain imaging has a low sensitivity. Magnetic resonance imaging (MRI or bone scan scintigraphy is the criterion standard, but expensive. We present the case of a young female distance runner with left shin pain. Plain radiography was unremarkable. Ultrasound showed focal hyperechoic elevation of the periosteum with irregularity over the distal tibia and increased flow on Doppler. These findings were consistent with a distal tibia stress fracture and confirmed by MRI. Examination of our case will highlight the utility of considering an ultrasound for diagnosis of tibial stress fracture.

  4. Exercise-induced rib stress fractures: influence of reduced bone mineral density

    DEFF Research Database (Denmark)

    Vinther, Anders; Kanstrup, Inge-Lis; Christiansen, Erik

    2005-01-01

    study investigated BMD in seven Danish national team rowers with previous rib stress fracture (RSF) and 7 controls (C) matched for gender, age, height, weight and training experience. Total body scan and specific scans of the lumbar spine (L2-L4), femoral neck and distal radius were performed using......Exercise-induced rib stress fractures have been reported frequently in elite rowers during the past decade. The etiology of rib stress fractures is unclear, but low bone mineral density (BMD) has been suggested to be a potential risk factor for stress fractures in weight-bearing bones. The present...... density may be a potential risk factor for the development of exercise-induced rib stress fractures in elite rowers....

  5. Stress Fracture and Nonunion of Coronoid Process in a Gymnast

    Directory of Open Access Journals (Sweden)

    T. Hetling

    2016-01-01

    Full Text Available Background. Gymnasts have high mechanical loading forces of up to 14 times body weight. Overuse lesions are typical in wrists and stress fractures in the olecranon, while isolated fractures of the coronoid process are uncommon. We present a case of retraumatized nonunion stress fracture of the ulnar coronoid process. Case Description. A 19-year-old gymnast presented with elbow pain after training. Imaging confirmed an old fracture of the coronoid process. We describe a 6-month multiphase return to competition rehabilitation program, which allowed him to compete pain-freely. Literature Review. Acute and overuse injuries in gymnasts are known but no nonunion of the coronoid process has been described before. Only one case of stress fracture of coronoid process in a gymnast was reported. Purpose and Clinical Relevance. We could successfully and conservatively return to sport a reactivated nonunion of a stress fracture of the coronoid process.

  6. Proximal tibial stress fracture associated with mild osteoarthritis of the knee: case report.

    Science.gov (United States)

    Curković, Marko; Kovac, Kristina; Curković, Bozidar; Babić-Naglić, Durda; Potocki, Kristina

    2011-03-01

    Stress fractures are considered as multifactorial overuse injuries occurring in 0.3%-0.8% of patients suffering from rheumatic diseases, with rheumatoid arthritis being the most common underlying condition. Stress fractures can be classified according to the condition of the bone affected as: 1) fatigue stress fractures occurring when normal bone is exposed to repeated abnormal stresses; and 2) insufficiency stress fractures that occur when normal stress is applied to bone weakened by an underlying condition. Stress fractures are rarely associated with severe forms of knee osteoarthritis, accompanied with malalignment and obesity. We present a patient with a proximal tibial stress fracture associated with mild knee osteoarthritis without associated malalignment or obesity. Stress fracture should be considered when a patient with osteoarthritis presents with sudden deterioration, severe localized tenderness to palpation and localized swelling or periosteal thickening at the pain site and elevated local temperature. The diagnosis of stress fractures in patients with rheumatic diseases may often be delayed because plain film radiographs may not reveal a stress fracture soon after the symptom onset; moreover, evidence of a fracture may never appear on plain radiographs. Triple phase nuclear bone scans and magnetic resonance imaging are more sensitive in the early clinical course than plain films for initial diagnosis.

  7. Longitudinal stress fracture of the tibia

    International Nuclear Information System (INIS)

    Lopez, J.M.; Onatibia, A.; Galardi, A.; Laso, C.

    1997-01-01

    We present two cases of lengthwise stress fracture in tibia. This is an atypical and uncommon presentation. We describe the major clinical and radiological findings, stressing the enormous importance of CT in the correct diagnosis. (Author) 6 refs

  8. Prospective study of ankle and foot fractures in elderly women

    Directory of Open Access Journals (Sweden)

    Yadagiri Surender Rao

    2015-01-01

    Full Text Available The epidemiology of ankle fractures in old people is changing as time passes on. The incidence of ankle fractures increases with advancing age. The study conducted was among a rural popula-tion which comprised of 68 women (32 women with ankle fractures & 36 women with foot fractures. Patients studied were in the age group more than 50 years. The study highlights the etiological & risk factors for fractures of ankle & foot. The commonest ankle fracture was the lateral malleolar fracture & the commonest foot fracture was the 5th Metatarsal fracture. Diabetes is a risk factor which increases the occurrence of ankle and foot injuries.

  9. The treatment of residual stress in fracture assessment of pressure vessels

    International Nuclear Information System (INIS)

    Green, D.; Knowles, J.

    1992-01-01

    The treatment of weld residual stress in the fracture assessment of cylindrical pressure vessels is considered through partitioning the stress into membrane, bending and self-balancing through wall components. The influence of each on fracture behavior is discussed. Stress intensity factor solutions appropriate to each type of stress are presented. Short range, medium range and long range stress categories are identified according to simple rules relating the effect of increasing crack length to stress intensity factor and ligament net stress. Proposals are made on how the stress intensity factor from these stress types may be incorporated into a Kr, Lr based fracture assessment

  10. The role of local stress perturbation on the simultaneous opening of orthogonal fractures

    Science.gov (United States)

    Boersma, Quinten; Hardebol, Nico; Barnhoorn, Auke; Bertotti, Giovanni; Drury, Martyn

    2016-04-01

    Orthogonal fracture networks (ladder-like networks) are arrangements that are commonly observed in outcrop studies. They form a particularly dense and well connected network which can play an important role in the effective permeability of tight hydrocarbon or geothermal reservoirs. One issue is the extent to which both the long systematic and smaller cross fractures can be simultaneously critically stressed under a given stress condition. Fractures in an orthogonal network form by opening mode-I displacements in which the main component is separation of the two fracture walls. This opening is driven by effective tensile stresses as the smallest principle stress acting perpendicular to the fracture wall, which accords with linear elastic fracture mechanics. What has been well recognized in previous field and modelling studies is how both the systematic fractures and perpendicular cross fractures require the minimum principle stress to act perpendicular to the fracture wall. Thus, these networks either require a rotation of the regional stress field or local perturbations in stress field. Using a mechanical finite element modelling software, a geological case of layer perpendicular systematic mode I opening fractures is generated. New in our study is that we not only address tensile stresses at the boundary, but also address models using pore fluid pressure. The local stress in between systematic fractures is then assessed in order to derive the probability and orientation of micro crack propagation using the theory of sub critical crack growth and Griffith's theory. Under effective tensile conditions, the results indicate that in between critically spaced systematic fractures, local effective tensile stresses flip. Therefore the orientation of the least principle stress will rotate 90°, hence an orthogonal fracture is more likely to form. Our new findings for models with pore fluid pressures instead of boundary tension show that the magnitude of effective tension

  11. Length scale of secondary stresses in fracture and fatigue

    International Nuclear Information System (INIS)

    Dong, P.

    2008-01-01

    In an attempt to provide a consistent framework for the analysis and treatment of secondary stresses associated with welding and thermal loading in the context of fracture mechanics, this paper starts with an effective stress characterization procedure by introducing a length-scale concept. With it, a traction-based stress separation procedure is then presented to provide a consistent characterization of stresses from various sources based on their length scale. Their relative contributions to fracture driving force are then quantified in terms of their characteristic length scales. Special attention is given to the implications of the length-scale argument on both analysis and treatment of welding residual stresses in fracture assessment. A series of examples is provided to demonstrate how the present developments can be applied for treating not only secondary stresses but also externally applied stresses, as well as their combined effects on the structural integrity of engineering components

  12. Dynamic Response in Transient Stress-Field Behavior Induced by Hydraulic Fracturing

    Science.gov (United States)

    Jenkins, Andrew

    Hydraulic fracturing is a technique which is used to exploit geologic features and subsurface properties in an effort to increase production in low-permeability formations. The process of hydraulic fracturing provides a greater surface contact area between the producing formation and the wellbore and thus increases the amount of recoverable hydrocarbons from within the reservoir. The use of this stimulation technique has brought on massive applause from the industry due to its widespread success and effectiveness, however the dynamic processes that take part in the development of hydraulic fractures is a relatively new area of research with respect to the massive scale operations that are seen today. The process of hydraulic fracturing relies upon understanding and exploiting the in-situ stress distribution throughout the area of study. These in-situ stress conditions are responsible for directing fracture orientation and propagation paths throughout the period of injection. The relative magnitude of these principle stresses is key in developing a successful stimulation plan. In horizontal well plan development the interpretation of stress within the reservoir is required for determining the azimuth of the horizontal well path. These horizontal laterals are typically oriented in a manner such that the well path lies parallel to the minimum horizontal stress. This allows for vertical fractures to develop transversely to the wellbore, or normal to the least principle stress without the theoretical possibility of fractures overlapping, creating the most efficient use of the fluid energy during injection. The orientation and magnitude of these in-situ stress fields however can be dynamic, controlled by the subsequent fracture propagation and redistribution of the surrounding stresses. That is, that as the fracture propagates throughout the reservoir, the relative stress fields surrounding the fractures may see a shift and deviate from their original direction or

  13. 'Cable-maker's clavicle': stress fracture of the medial clavicle

    International Nuclear Information System (INIS)

    Peebles, C.R.; Sulkin, T.; Sampson, M.A.

    2000-01-01

    A 50-year-old man presented with a non-traumatic painful swelling over the medial clavicle. Radiographs showed a poorly defined fracture and the possibility of an underlying pathology was raised. Computed tomography suggested a stress fracture. This prompted a further, more detailed occupational history to be obtained from the patient, which revealed a hitherto undescribed cause of clavicular stress fracture and obviated the need for further imaging or biopsy. (orig.)

  14. Stress Fractures of the Foot.

    Science.gov (United States)

    Hossain, Munier; Clutton, Juliet; Ridgewell, Mark; Lyons, Kathleen; Perera, Anthony

    2015-10-01

    Stress fractures of the foot and ankle may be more common among athletes than previously reported. A low threshold for investigation is warranted and further imaging may be appropriate if initial radiographs remain inconclusive. Most of these fractures can be treated conservatively with a period of non-weight-bearing mobilization followed by gradual return to activity. Early surgery augmented by bone graft may allow athletes to return to sports earlier. Risk of delayed union, nonunion, and recurrent fracture is high. Many of the patients may also have risk factors for injury that should be modified for a successful outcome. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Taking a holistic approach to managing difficult stress fractures.

    Science.gov (United States)

    Miller, Timothy L; Best, Thomas M

    2016-09-09

    Stress fractures and other bony stress injuries occur along a spectrum of severity which can impact treatment and prognosis. When treating these injuries, it should be borne in mind that no two stress fractures behave exactly alike. Given that they are not a consistent injury, standardized treatment protocols can be challenging to develop. Treatment should be individualized to the patient or athlete, the causative activity, the anatomical site, and the severity of the injury. A holistic approach to the treatment of the most difficult stress fractures should be taken by orthopedists and sports medicine specialists. This approach is necessary to obtain optimal outcomes, minimize loss of fitness and time away from sports participation, and decrease the risk of recurrence.

  16. Stress analysis of implant-bone fixation at different fracture angle

    Science.gov (United States)

    Izzawati, B.; Daud, R.; Afendi, M.; Majid, MS Abdul; Zain, N. A. M.; Bajuri, Y.

    2017-10-01

    Internal fixation is a mechanism purposed to maintain and protect the reduction of a fracture. Understanding of the fixation stability is necessary to determine parameters influence the mechanical stability and the risk of implant failure. A static structural analysis on a bone fracture fixation was developed to simulate and analyse the biomechanics of a diaphysis shaft fracture with a compression plate and conventional screws. This study aims to determine a critical area of the implant to be fractured based on different implant material and angle of fracture (i.e. 0°, 30° and 45°). Several factors were shown to influence stability to implant after surgical. The stainless steel, (S. S) and Titanium, (Ti) screws experienced the highest stress at 30° fracture angle. The fracture angle had a most significant effect on the conventional screw as compared to the compression plate. The stress was significantly higher in S.S material as compared to Ti material, with concentrated on the 4th screw for all range of fracture angle. It was also noted that the screws closest to the intense concentration stress areas on the compression plate experienced increasing amounts of stress. The highest was observed at the screw thread-head junction.

  17. The ``gray cortex``: an early sign of stress fracture

    Energy Technology Data Exchange (ETDEWEB)

    Mulligan, M.E. [Dept. of Radiology, Univ. of Maryland Medical Center, Baltimore, MD (United States)

    1995-04-01

    The purpose of this report is to describe an early radiographic sign of stress fracture, the ``gray cortex.`` The imaging findings in three patients with tibial stress fractures were reviewed. The ``gray cortex`` sign was evident on the initial conventional radiographs in all three cases. It was prospectively reported as a sign of stress fracture in two patients and was evident on the initial radiographs (taken elsewhere) of the third patient, who was referred for additional workup of a possible neoplasm. Special imaging studies (technetium-99m bone scan, computed tomography, and magnetic resonance imaging) confirmed the diagnosis in all three cases. (orig.)

  18. The ''gray cortex'': an early sign of stress fracture

    International Nuclear Information System (INIS)

    Mulligan, M.E.

    1995-01-01

    The purpose of this report is to describe an early radiographic sign of stress fracture, the ''gray cortex.'' The imaging findings in three patients with tibial stress fractures were reviewed. The ''gray cortex'' sign was evident on the initial conventional radiographs in all three cases. It was prospectively reported as a sign of stress fracture in two patients and was evident on the initial radiographs (taken elsewhere) of the third patient, who was referred for additional workup of a possible neoplasm. Special imaging studies (technetium-99m bone scan, computed tomography, and magnetic resonance imaging) confirmed the diagnosis in all three cases. (orig.)

  19. An Unusual Stress Fracture in an Archer with Hypophosphatasia

    Directory of Open Access Journals (Sweden)

    Umut Yavuz

    2013-01-01

    Full Text Available We report a 45-year-old male archer with stress fracture in his left ulna on the background of adult type of hypophosphatasia. The patient presented to several medical centers for pain around the left elbow and received medical treatment upon diagnosis of tenosynovitis. History of the patient revealed that he had had diagnosis of hypophosphatasia ten years ago and underwent percutaneous screwing for stress fracture on both of his femoral necks. Upon finding nondisplaced stress fracture on proximal metaphysis of the ulna on X-ray, the patient underwent magnetic resonance imaging (MRI in order to exclude pathological causes. No additional pathology was observed in MRI scanning. The patient’s sportive activities were restricted for 6 weeks and he received conservative management with arm slings. Adult type of hypophosphatasia is a disease manifesting with widespread osteoporosis and presenting with low serum level of alkali phosphatase (ALP. Stress fracture should definitely be considered in the patients with history of hypophosphatasia and refractory extremity pain.

  20. Tensile Properties of the Deep Transverse Metatarsal Ligament in Hallux Valgus: A CONSORT-Compliant Article.

    Science.gov (United States)

    Abdalbary, Sahar Ahmed; Elshaarawy, Ehab A A; Khalid, Bahaa E A

    2016-02-01

    The deep transverse metatarsal ligament (DTML) connects the neighboring2 metatarsal heads and is one of the stabilizers connecting the lateral sesamoid and second metatarsal head. In this study, we aimed to determine the tensile properties of the DTML in normal specimens and to compare these results with hallux valgus specimens. We hypothesized that the tensile properties of the DTML would be different between the 2 groups of specimens.The DTML in the first interspace was dissected from 12 fresh frozen human cadaveric specimens. Six cadavers had bilateral hallux valgus and the other 6 cadavers had normal feet. The initial length (L0) and cross-sectional area (A0) of the DTML were measured using a digital caliper, and tensile tests with load failure were performed using a material testing machine.There were significant between-groups differences in the initial length (L0) P = 0.009 and cross-sectional area (A0) of the DTML P = 0.007. There were also significant between-groups differences for maximum force (N) P = 0.004, maximum distance (mm) P = 0.005, maximum stress (N/mm) P = 0.003, and maximum strain (%) P = 0.006.The DTML is an anatomical structure for which the tensile properties differ in hallux valgus.

  1. Stress Fractures of Tibia Treated with Ilizarov External Fixator.

    Science.gov (United States)

    Górski, Radosław; Żarek, Sławomir; Modzelewski, Piotr; Górski, Ryszard; Małdyk, Paweł

    2016-08-30

    Stress fractures are the result of cyclic loading of the bone, which gradually becomes damaged. Most often they are treated by rest or plaster cast and, in rare cases, by internal fixation. There is little published data on initial reposition followed by stabilization with the Ilizarov apparatus in such fractures. Six patients were treated with an external fixator according to the Ilizarov method for a stress fracture of the tibia between 2007 and 2015. Three patients were initially treated conservatively. Due to increasing tibial deformation, they were qualified for surgical treatment with external stabilization. In the other patients, surgery was the first-line treatment. All patients demonstrated risk factors for a stress fracture. After the surgery, they fully loaded the operated limb. No patient developed malunion, nonunion, infection or venous thrombosis. The average time from the first operation to the removal of the external fixator was 19 weeks. Radiographic and clinical outcomes were satisfactory in all patients. 1. The Ilizarov method allows for successful stabilization of stress fractures of the tibia. 2. It may be a good alternative to internal stabilization, especially in patients with multiple comorbidities which affect bone quality and may impair soft tissue healing.

  2. Stress fractures: definition, diagnosis and treatment.

    Science.gov (United States)

    Astur, Diego Costa; Zanatta, Fernando; Arliani, Gustavo Gonçalves; Moraes, Eduardo Ramalho; Pochini, Alberto de Castro; Ejnisman, Benno

    2016-01-01

    Stress fractures were first described in Prussian soldiers by Breithaupt in 1855. They occur as the result of repeatedly making the same movement in a specific region, which can lead to fatigue and imbalance between osteoblast and osteoclast activity, thus favoring bone breakage. In addition, when a particular region of the body is used in the wrong way, a stress fracture can occur even without the occurrence of an excessive number of functional cycles. The objective of this study was to review the most relevant literature of recent years in order to add key information regarding this pathological condition, as an updating article on this topic.

  3. Risk factors for stress fracture among young female cross-country runners.

    Science.gov (United States)

    Kelsey, Jennifer L; Bachrach, Laura K; Procter-Gray, Elizabeth; Nieves, Jeri; Greendale, Gail A; Sowers, Maryfran; Brown, Byron W; Matheson, Kim A; Crawford, Sybil L; Cobb, Kristin L

    2007-09-01

    To identify risk factors for stress fracture among young female distance runners. Participants were 127 competitive female distance runners, aged 18-26, who provided at least some follow-up data in a randomized trial among 150 runners of the effects of oral contraceptives on bone health. After completing a baseline questionnaire and undergoing bone densitometry, they were followed an average of 1.85 yr. Eighteen participants had at least one stress fracture during follow-up. Baseline characteristics associated (Pstress fracture occurrence were one or more previous stress fractures (rate ratio [RR] [95% confidence interval]=6.42 (1.80-22.87), lower whole-body bone mineral content (RR=2.70 [1.26-5.88] per 1-SD [293.2 g] decrease), younger chronologic age (RR=1.42 [1.05-1.92] per 1-yr decrease), lower dietary calcium intake (RR=1.11 [0.98-1.25] per 100-mg decrease), and younger age at menarche (RR=1.92 [1.15-3.23] per 1-yr decrease). Although not statistically significant, a history of irregular menstrual periods was also associated with increased risk (RR=3.41 [0.69-16.91]). Training-related factors did not affect risk. The results of this and other studies indicate that risk factors for stress fracture among young female runners include previous stress fractures, lower bone mass, and, although not statistically significant in this study, menstrual irregularity. More study is needed of the associations between stress fracture and age, calcium intake, and age at menarche. Given the importance of stress fractures to runners, identifying preventive measures is of high priority.

  4. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    Science.gov (United States)

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. NextGen Stress & Fracture for Lightweight Structures

    Data.gov (United States)

    National Aeronautics and Space Administration — The dream in stress and fracture analysis has always been to be able to simulate cracks initiating and then propagating in a stress field in a metal or composite...

  6. Stress- and Chemistry-Mediated Permeability Enhancement/Degradation in Stimulated Critically-Stressed Fractures

    Energy Technology Data Exchange (ETDEWEB)

    Derek Elsworth; Abraham S. Grader; Chris Marone; Phillip Halleck; Peter Rose; Igor Faoro; Joshua Taron; André Niemeijer; Hideaki Yasuhara

    2009-03-30

    This work has investigated the interactions between stress and chemistry in controlling the evolution of permeability in stimulated fractured reservoirs through an integrated program of experimentation and modeling. Flow-through experiments on natural and artificial fractures in Coso diorite have examined the evolution of permeability under paths of mean and deviatoric stresses, including the role of dissolution and precipitation. Models accommodating these behaviors have examined the importance of incorporating the complex couplings between stress and chemistry in examining the evolution of permeability in EGS reservoirs. This document reports the findings of experiment [1,2] and analysis [3,4], in four sequential chapters.

  7. A Discrete Fracture Network Model with Stress-Driven Nucleation and Growth

    Science.gov (United States)

    Lavoine, E.; Darcel, C.; Munier, R.; Davy, P.

    2017-12-01

    The realism of Discrete Fracture Network (DFN) models, beyond the bulk statistical properties, relies on the spatial organization of fractures, which is not issued by purely stochastic DFN models. The realism can be improved by injecting prior information in DFN from a better knowledge of the geological fracturing processes. We first develop a model using simple kinematic rules for mimicking the growth of fractures from nucleation to arrest, in order to evaluate the consequences of the DFN structure on the network connectivity and flow properties. The model generates fracture networks with power-law scaling distributions and a percentage of T-intersections that are consistent with field observations. Nevertheless, a larger complexity relying on the spatial variability of natural fractures positions cannot be explained by the random nucleation process. We propose to introduce a stress-driven nucleation in the timewise process of this kinematic model to study the correlations between nucleation, growth and existing fracture patterns. The method uses the stress field generated by existing fractures and remote stress as an input for a Monte-Carlo sampling of nuclei centers at each time step. Networks so generated are found to have correlations over a large range of scales, with a correlation dimension that varies with time and with the function that relates the nucleation probability to stress. A sensibility analysis of input parameters has been performed in 3D to quantify the influence of fractures and remote stress field orientations.

  8. Postpartum osteoporosis associated with proximal tibial stress fracture

    Energy Technology Data Exchange (ETDEWEB)

    Clemetson, I.A.; Anderson, S.E. [Department of Radiology, University Hospital of Bern, Inselspital, 3010, Bern (Switzerland); Popp, A.; Lippuner, K. [Department of Osteology, University Hospital of Bern, Inselspital, 3010, Bern (Switzerland); Ballmer, F. [Knee and Sports Medicine Unit, Lindenhofspital Bern, 3012, Bern (Switzerland)

    2004-02-01

    A 33-year-old woman presented with acute nonspecific knee pain, 6 months postpartum. MR imaging, computed tomography and radiography were performed and a proximal tibia plateau insufficiency fracture was detected. Bone densitometry demonstrated mild postpartum osteoporosis. To our knowledge these findings have not been described in this location and in this clinical setting. The etiology of the atraumatic fracture of the tibia is presumed to be due to a low bone mineral density. The bone loss was probably due to pregnancy, lactation and postpartum hormonal changes. There were no other inciting causes and the patient was normocalcemic. We discuss the presence of a postpartum stress fracture in a hitherto undescribed site in a patient who had lactated following an uncomplicated pregnancy and had no other identifiable cause for a stress fracture. (orig.)

  9. Postpartum osteoporosis associated with proximal tibial stress fracture

    International Nuclear Information System (INIS)

    Clemetson, I.A.; Anderson, S.E.; Popp, A.; Lippuner, K.; Ballmer, F.

    2004-01-01

    A 33-year-old woman presented with acute nonspecific knee pain, 6 months postpartum. MR imaging, computed tomography and radiography were performed and a proximal tibia plateau insufficiency fracture was detected. Bone densitometry demonstrated mild postpartum osteoporosis. To our knowledge these findings have not been described in this location and in this clinical setting. The etiology of the atraumatic fracture of the tibia is presumed to be due to a low bone mineral density. The bone loss was probably due to pregnancy, lactation and postpartum hormonal changes. There were no other inciting causes and the patient was normocalcemic. We discuss the presence of a postpartum stress fracture in a hitherto undescribed site in a patient who had lactated following an uncomplicated pregnancy and had no other identifiable cause for a stress fracture. (orig.)

  10. Measurement of residual stresses using fracture mechanics weight functions

    International Nuclear Information System (INIS)

    Fan, Y.

    2000-01-01

    A residual stress measurement method has been developed to quantify through-the-thickness residual stresses. Accurate measurement of residual stresses is crucial for many engineering structures. Fabrication processes such as welding and machining generate residual stresses that are difficult to predict. Residual stresses affect the integrity of structures through promoting failures due to brittle fracture, fatigue, stress corrosion cracking, and wear. In this work, the weight function theory of fracture mechanics is used to measure residual stresses. The weight function theory is an important development in computational fracture mechanics. Stress intensity factors for arbitrary stress distribution on the crack faces can be accurately and efficiently computed for predicting crack growth. This paper demonstrates that the weight functions are equally useful in measuring residual stresses. In this method, an artificial crack is created by a thin cut in a structure containing residual stresses. The cut relieves the residual stresses normal to the crack-face and allows the relieved residual stresses to deform the structure. Strain gages placed adjacent to the cut measure the relieved strains corresponding to incrementally increasing depths of the cut. The weight functions of the cracked body relate the measured strains to the residual stresses normal to the cut within the structure. The procedure details, such as numerical integration of the singular functions in applying the weight function method, will be discussed

  11. Measurement of residual stresses using fracture mechanics weight functions

    International Nuclear Information System (INIS)

    Fan, Y.

    2001-01-01

    A residual stress measurement method has been developed to quantify through-the-thickness residual stresses. Accurate measurement of residual stresses is crucial for many engineering structures. Fabrication processes such as welding and machining generate residual stresses that are difficult to predict. Residual stresses affect the integrity of structures through promoting failures due to brittle fracture, fatigue, stress corrosion cracking, and wear. In this work, the weight function theory of fracture mechanics is used to measure residual stresses. The weight function theory is an important development in computational fracture mechanics. Stress intensity factors for arbitrary stress distribution on the crack faces can be accurately and efficiently computed for predicting crack growth. This paper demonstrates that the weight functions are equally useful in measuring residual stresses. In this method, an artificial crack is created by a thin cut in a structure containing residual stresses. The cut relieves the residual stresses normal to the crack-face and allows the relieved residual stresses to deform the structure. Strain gages placed adjacent to the cut measure the relieved strains corresponding to incrementally increasing depths of the cut. The weight functions of the cracked body relate the measured strains to the residual stresses normal to the cut within the structure. The procedure details, such as numerical integration of the singular functions in applying the weight function method, will be discussed. (author)

  12. The Contribution of SPECT/CT in the Diagnosis of Stress Fracture of the Proximal Tibia.

    Science.gov (United States)

    Okudan, Berna; Coşkun, Nazım; Arıcan, Pelin

    2018-02-01

    Stress fractures are injuries most commonly seen in the lower limbs and are usually caused by repetitive stress. While the distal and middle third of the tibia is the most frequent site for stress fractures (almost 50%), stress fractures of the proximal tibia is relatively rare and could be confused with other types of tibial fractures, thus altering management plans for the clinician. Early diagnosis of stress fractures is also important to avoid complications. Imaging plays an important role in the diagnosis of stress fractures, especially bone scan. Combined with single-photon emission computed tomography/computed tomography (SPECT/CT) it is an important imaging technique for stress fractures in both upper and lower extremities, and is widely preferred over other imaging techniques. In this case, we present the case of a 39-year-old male patient diagnosed with stress fracture of the proximal tibia and demonstrate the contribution of CT scan fused with SPECT imaging in the early diagnosis of stress fracture prior to other imaging modalities.

  13. Biomechanical consequences of adding plantar fascia release to metatarsal osteotomies: Changes in forefoot plantar pressures.

    Science.gov (United States)

    Aydogan, Umur; Roush, Evan P; Moore, Blake E; Andrews, Seth H; Lewis, Gregory S

    2017-04-01

    Destruction of the normal metatarsal arch by a long metatarsal is often a cause for metatarsalgia. When surgery is warranted, distal oblique, or proximal dorsiflexion osteotomies of the long metatarsal bones are commonly used. The plantar fascia has anatomical connection to all metatarsal heads. There is controversial scientific evidence on the effect of plantar fascia release on forefoot biomechanics. In this cadaveric biomechanical study, we hypothesized that plantar fascia release would augment the plantar metatarsal pressure decreasing effects of two common second metatarsal osteotomy techniques. Six matched pairs of foot and ankle specimens were mounted on a pressure mat loading platform. Two randomly assigned surgery groups, which had received either distal oblique, or proximal dorsiflexion osteotomy of the second metatarsal, were evaluated before and after plantar fasciectomy. Specimens were loaded up to a ground reaction force of 400 N at varying Achilles tendon forces. Average pressures, peak pressures, and contact areas were analyzed. Supporting our hypothesis, average pressures under the second metatarsal during 600 N Achilles load were decreased by plantar fascia release following proximal osteotomy (p plantar fascia release following modified distal osteotomy, under multiple Achilles loading conditions (p Plantar fasciotomy should not be added to distal metatarsal osteotomy in the treatment of metatarsalgia. If proximal dorsiflexion osteotomy would be preferred, plantar fasciotomy should be approached cautiously not to disturb the forefoot biomechanics. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:800-804, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  14. Acetabular stress fractures in military endurance athletes and recruits: incidence and MRI and scintigraphic findings

    International Nuclear Information System (INIS)

    Williams, T.R.; Puckett, M.L.; Shin, A.Y.; Gorman, J.D.; Denison, G.

    2002-01-01

    Objective: To evaluate the incidence and the MRI and scintigraphic appearance of acetabular stress (fatigue) fractures in military endurance athletes and recruits. Design and patients: One hundred and seventy-eight active duty military endurance trainees with a history of activity-related hip pain were evaluated by both MRI and bone scan over a 2-year period. Patients in the study ranged in age from 17 to 45 years. They had hip pain related to activity and had plain radiographs of the hip and pelvis that were interpreted as normal or equivocal. The study was originally designed to evaluate the MRI and scintigraphic appearance of femoral neck stress fractures. Patients had scintigraphy and a limited MRI examination (coronal imaging only) within 48 h of the bone scan. Twelve patients demonstrated imaging findings compatible with acetabular stress fractures. Results: Stress fractures are common in endurance athletes and in military populations; however, stress fracture of the acetabulum is uncommon. Twelve of 178 patients (6.7%) in our study had imaging findings consistent with acetabular stress fractures. Two patterns were identified. Seven of the 12 (58%) patients had acetabular roof stress fractures. In this group, two cases of bilateral acetabular roof stress fractures were identified, one with a synchronous tensile sided femoral neck stress fracture. The remaining five of 12 (42%) patients had anterior column stress fractures, rarely occurring in isolation, and almost always occurring with inferior pubic ramus stress fracture (4 of 5, or 80%). One case of bilateral anterior column stress fractures was identified without additional sites of injury. Conclusions: Stress fractures are commonplace in military populations, especially endurance trainees. Acetabular stress fractures are rare and therefore unrecognized, but do occur and may be a cause for activity-related hip pain in a small percentage of military endurance athletes and recruits. (orig.)

  15. Fracture mechanical treatment of bridging stresses in ceramics

    International Nuclear Information System (INIS)

    Fett, T.; Munz, D.

    1993-12-01

    Failure of ceramic materials often starts from cracks which can originate at pores, inclusions or can be generated during surface treatment. Fracture occurs when the stress intensity factor of the most serious crack in a component reaches a critical value K lc , the fracture toughness of the material. In case of ideal brittle materials the fracture toughness is independent of the crack extension and, consequently, identical with the stress intensity factor K l0 necessary for the onset of stable crack growth. It is a well-known fact that failure of several ceramics is influenced by an increasing crack-growth resistance curve. Several effects are responsible for this behaviour. Crack-border interactions in the wake of the advancing crack, residual stress fields in the crack region of transformation-toughened ceramics, the generation of a micro-crack zone ahead the crack tip and crack branching. The effect of increasing crack resistance has consequences on many properties of ceramic materials. In this report the authors discuss the some aspects of R-curve behaviour as the representation by stress intensity factors or energies and the influence on the compliance using the bridging stress model. (orig.) [de

  16. The effect of stress fracture interventions in a single elite infantry training unit (1983-2015).

    Science.gov (United States)

    Milgrom, Charles; Finestone, Aharon S

    2017-10-01

    Stress fractures can be seen as an undesired byproduct of demanding physical training. The threshold value of stress that places an individual bone at high risk for stress fracture has not been identified. In a prospective study of stress fractures in 1983, a 31% incidence was found during demanding Israeli infantry basic training by bone scan criteria. Within a subgroup of these recruits, an elite infantry unit was found to have a 40% incidence. Since then and until 2015, eight additional induction companies of the same elite infantry unit were prospectively monitored for stress fractures during their basic training. In all of the studies, stress fracture surveillance and the examining orthopedist were the same. A retrospective review of all nine studies and of eight training changes was performed to look for a temporal trend in stress fracture incidence and to see if these might be related to training changes. There was a statistically significant trend for lower radiological proven stress fractures (p=0.0001) and radiological proven stress fractures plus clinical stress fractures (p=0.0013), as well as lower stress fracture severity by radiological criteria (p=0.0001) between 1983 and 2015. The only training change that was associated, by multivariate logistic regression, with a decreased incidence of stress fracture was restricting training to the authorized training protocol (odds ratio, 3874; 95% CI, 1.526 to 9.931; p=0.004). Increased recruit weight was found by multivariate analysis to be associated with lower stress fracture incidence (odds ratio 1.034; 95% CI, 1.00 to 1.070; p=0.051). Moving the training to a base with flatter terrain and reducing the formal marching distance by 1/3 was associated with a decrease in high grade stress fractures (odds ratio, 10.03; 95% CI, 3.5 to 28.4; p=0.0001). Neither the combined changes of enforcing a seven hour a night sleep regimen, training in more comfortable boots and adding a physical therapist to the unit nor

  17. Pathology of the distal condyles of the third metacarpal and third metatarsal bones of the horse

    International Nuclear Information System (INIS)

    Riggs, C.M.; Whitehouse, G.H.; Boyde, A.

    1999-01-01

    This study examined material from Thoroughbred horses, the majority of which had been in race training, for evidence of pathology in the third metacarpal (McIII) and third metatarsal (MtIII) bones which might be related to the occurrence of distal condylar fractures. Whole bone samples were studied and documented by macrophotography prior to macroradiography and computed tomographic (CT) imaging. Microradiographs were made from 100 microm thick mediolateral sections cut perpendicular to the dorsal and palmar/plantar articular surfaces of distal condylar regions of McIII and MtIII. Blocks were prepared for morphological imaging using the backscattered electron mode of scanning electron microscopy (BSE SEM). Linear defects in mineralised articular cartilage and subchondral bone were found in the palmar/plantar aspects of the condylar grooves adjacent to the sagittal ridge. These were closely related to the pattern of densification of the subchondral bone and were associated with intense focal remodelling of the immediately adjacent and subjacent bone. Parasagittal fractures of the condyles originated in similar defects. A unifying hypothesis for the aetiopathogenesis of these fractures is presented

  18. Multiple floating metatarsals: a unique injury

    Directory of Open Access Journals (Sweden)

    Trikha Vivek

    2013-04-01

    Full Text Available 【Abstract】Concomitant dislocation of the tar-sometatarsal and metatarsophalangeal joints of foot is an extremely rare injury. Such injuries presenting in a single or adjacent dual rays have been described in few cases previously. We describe such an injury in adjacent three metatarsals of a polytrauma patient. These injuries are likely to be missed in the initial assessment of a polytrauma patient. These patients are at risk of an overlooked diagnosis but the consequences of missing this type of injury may be Vivek Trikha*, Tarun Goyal, Amit K Agarwal quite severe. This case is presented in view of its unique-ness along with possible mechanism of injury, the sequence of reduction and follow-up. Knowledge of such injury and its proper management may be useful to the trauma surgeons. Key words: Metatarsal bones; Metatarsophalangeal joint; Wounds and injuries

  19. Multiple stress fractures in a young female runner.

    Science.gov (United States)

    Dusek, T; Pećina, M; Loncar-Dusek, M; Bojanic, I

    2004-01-01

    The effect of exercise on female's bone metabolism has received much attention in recent years. We report on unusual case of a female runner with low body mass and amenorrhea, who suffered 4 stress fractures. Three of the stress fractures occurred during her sports career, and the fourth occurred 7 years after the cessation of sports activities. It seems that exercise-induced amenorrhea together with food restriction in the young age may cause long-term consequences on bone metabolism.

  20. The Contribution of SPECT/CT in the Diagnosis of Stress Fracture of the Proximal Tibia

    Directory of Open Access Journals (Sweden)

    Berna Okudan

    2018-02-01

    Full Text Available Stress fractures are injuries most commonly seen in the lower limbs and are usually caused by repetitive stress. While the distal and middle third of the tibia is the most frequent site for stress fractures (almost 50%, stress fractures of the proximal tibia is relatively rare and could be confused with other types of tibial fractures, thus altering management plans for the clinician. Early diagnosis of stress fractures is also important to avoid complications. Imaging plays an important role in the diagnosis of stress fractures, especially bone scan. Combined with single-photon emission computed tomography/computed tomography (SPECT/CT it is an important imaging technique for stress fractures in both upper and lower extremities, and is widely preferred over other imaging techniques. In this case, we present the case of a 39-year-old male patient diagnosed with stress fracture of the proximal tibia and demonstrate the contribution of CT scan fused with SPECT imaging in the early diagnosis of stress fracture prior to other imaging modalities.

  1. Fracture predictions for cracks exposed to superimposed normal and shear stresses

    International Nuclear Information System (INIS)

    Richard, H.A.

    1985-01-01

    The author developed a special device and a fracture mechanics specimen and proposed a procedure for determining the fracture toughness when Mixed Mode and Mode II stresses are applied. This device makes it possible to generate pure normal stresses, superimposed normal and shearing stresses as well as pure shearing stresses in the cross section of the crack in the specimen, as desired. The so-called CTS fracture mechanics specimen has an edge crack. The load is transferred statically determind from the device to the specimen by means of six studs altogether. The experiments described, which were carried out with specimens made of the brittle materials PMMA (Plexiglas) and Araldit B, clearly show that it is possible to evaluate the validity of the individual fracture hypotheses by suitable experiments. It is also found that the fracture behaviour of different materials varies considerably both in quality and quantity. In conclusion, a practice-oriented fracture criterion is indicated which enables a practice-conforming evaluation of Mixed-Mode crack problems, as is shown by way of examples. (orig./HP) [de

  2. Stress fracture in posterior aspect of the tibia

    International Nuclear Information System (INIS)

    Moon, Tae Yong; Jung, Hyun Woo; Park, Chung Hun; Chun, Kyung Ah; Koo, Bong Sig; Lee, Sang Yong

    1999-01-01

    To determine correlation between stress fracture of the posterior tibia and flexor digitorum longus muscle injury caused by athletic or sporting activity during adolescence. Eleven cases diagnosed as stress fracture after X-ray and MR imaging of the lower leg were reviewed. With regard to each fracture, the following features were noted : age, sex, and athletic or sporting activity of the patient, and site. Using MR imaging techniques, axial and sagittal T1 and T2 weighted imaged were obtained in all cases and T1-Gd DTPA images in seven. The activities undertaken were running (n=3), football (n=2), ballet (n=2), taekwando (n=1), badminton (n=1), field hockey (n=1), and basketball (n=1). MR images revealed localized cortical thickness (n=11), linear intramedullary callus showing a low signal on T1 and T2 weighted images (n=9), marrow hyperemia (n=7), and flexor digitorum longus muscle injury showing a high signal on T1-Gd DTPA and T2 weighted image (n=7). Stress fracture of the posterior tibia might be induced by flexor digitorum longus muscle activity induced by athletic or sporting activities during adolescence

  3. Stress fracture in posterior aspect of the tibia

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Tae Yong; Jung, Hyun Woo; Park, Chung Hun [Pusan National Univ. College of Medicine, Pusan (Korea, Republic of); Chun, Kyung Ah [Catholic Univ Hospital, Pusan (Korea, Republic of); Koo, Bong Sig [Donga Univ. Hospital, Pusan (Korea, Republic of); Lee, Sang Yong [Chunbuk Natinoal Univ. Hospital, Chunju (Korea, Republic of)

    1999-01-01

    To determine correlation between stress fracture of the posterior tibia and flexor digitorum longus muscle injury caused by athletic or sporting activity during adolescence. Eleven cases diagnosed as stress fracture after X-ray and MR imaging of the lower leg were reviewed. With regard to each fracture, the following features were noted : age, sex, and athletic or sporting activity of the patient, and site. Using MR imaging techniques, axial and sagittal T1 and T2 weighted imaged were obtained in all cases and T1-Gd DTPA images in seven. The activities undertaken were running (n=3), football (n=2), ballet (n=2), taekwando (n=1), badminton (n=1), field hockey (n=1), and basketball (n=1). MR images revealed localized cortical thickness (n=11), linear intramedullary callus showing a low signal on T1 and T2 weighted images (n=9), marrow hyperemia (n=7), and flexor digitorum longus muscle injury showing a high signal on T1-Gd DTPA and T2 weighted image (n=7). Stress fracture of the posterior tibia might be induced by flexor digitorum longus muscle activity induced by athletic or sporting activities during adolescence.

  4. Stress fracture risk factors in female football players and their clinical implications.

    Science.gov (United States)

    Warden, Stuart J; Creaby, Mark W; Bryant, Adam L; Crossley, Kay M

    2007-08-01

    A stress fracture represents the inability of the skeleton to withstand repetitive bouts of mechanical loading, which results in structural fatigue, and resultant signs and symptoms of localised pain and tenderness. Reports of stress fractures in female football players are not prevalent; however, they are probably under-reported and their importance lies in the morbidity that they cause in terms of time lost from participation. By considering risk factors for stress fractures in female football players it may be possible to reduce the impact of these troublesome injuries. Risk factors for stress fractures in female football players include intrinsic risk factors such as gender, endocrine, nutritional, physical fitness and neuromusculoskeletal factors, as well as extrinsic risk factors such as training programme, equipment and environmental factors. This paper discusses these risk factors and their implications in terms of developing prevention and management strategies for stress fractures in female football players.

  5. First-rib stress fracture in two adolescent swimmers: a case report.

    Science.gov (United States)

    Low, Sara; Kern, Michael; Atanda, Alfred

    2016-01-01

    First-rib stress fractures have been described in adolescent athletes in various sports, with only one prior case report of first-rib stress fractures in an adolescent female swimmer. There is a need for research on the cause, management, and prevention of these injuries as they lead to significant morbidity and critical time away from sport for these aspiring athletes. We aimed to describe first-rib stress fractures as a potential cause for non-specific atraumatic chronic shoulder pain in adolescent swimmers and to discuss the different presentations, unique risk factors, treatment, and potential injury prevention strategies of such fractures. We discussed two such cases which were successfully treated with activity modification with restriction of all overhead activity, gradually progressive physical therapy and a return to swimming protocol. First-rib stress fractures can vary in presentation and should be in the differential diagnosis in adolescent swimmers with chronic shoulder pain. These injuries can be successfully managed with rest from overhead activities and physical therapy. Gradual return to competitive swimming can be achieved even with non-union of a first-rib stress fracture. Emphasis on balanced strength training in different muscle groups and proper swimming technique is essential to prevent these injuries.

  6. Unusual longitudinal stress fractures of the femoral diaphysis: report of five cases

    International Nuclear Information System (INIS)

    Williams, M.; Timsit, M.A.; Karneff, A.; Pertuiset, E.

    1999-01-01

    We present five cases of a distinctive type of longitudinal stress fracture of the upper femoral shaft in which the fracture line is parallel to the outer surface of the bone, in contrast to the perpendicular orientation to the cortical surface in previously reported cases of diaphyseal stress fractures. In two cases the fracture recurred after 15 and 18 months, respectively. (orig.)

  7. Bilateral First Rib Stress Fractures in a Basketball Player

    Directory of Open Access Journals (Sweden)

    Abidin (Radyoloji Kilincer

    2016-04-01

    Full Text Available I read the article published by Aydogdu et al with a great interest. I congratulate them for this successfully written case report. Additionally, I want to focus an important point about the case they presented is that the diagnosis in that case is likely stress fracture. It is understood from the text and title that they avoided to make a diagnosis of stress fracture in the case, despite of history of lifting heavy weights for three days. And also I decided to mention through this article to an example of our case with bilateral first rib old fractures.

  8. Acoustic Emission Based Surveillance System for Prediction of Stress Fractures

    Science.gov (United States)

    2007-09-01

    aging are susceptible to such fractures in contexts of osteoporosis, diabetes, cerebral palsy, fibrous dysplasia and osteogenesis imperfecta . This...disease, or, healthy people who have excessive exercise regimes (soldiers and athletes) experience these fractures [2]. Stress fractures interrupt

  9. Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study.

    Science.gov (United States)

    Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-Ichi

    2017-06-18

    To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fracture and the geometry of the tibial plateau were reviewed and measured on MRI. Thirteen of 14 stress fractures were linear, and one of them stellated on MRI images. The location of fractures was classified into three types. Three fractures were located anteromedially (AM type), six posteromedially (PM type), and five posteriorly (P type) at the medial tibial plateau. In addition, tibial posterior slope at the medial tibial plateau tended to be larger when the fracture was located more posteriorly on MRI. We found that MRI showed three different localizations of medial tibial plateau stress fractures, which were associated with tibial posterior slope at the medial tibial plateau.

  10. Influence of Bone Remodeling Inhibition on the Development of Experimental Stress Fractures

    National Research Council Canada - National Science Library

    Schaffler, Mitchell B

    2005-01-01

    .... Using a bisphosphonate (BIS) to suppress remodeling in the rabbit tibial stress fracture model, we found that antiresorptive therapy reduced the intensity of the stress fracture response in this model...

  11. Metatarsal lengthening by callotasis in adults with first brachymetatarsia.

    Science.gov (United States)

    Hwang, So-Min; Song, Jennifer Kim; Kim, Hui-Taek

    2012-12-01

    Brachymetatarsia is a rare clinical entity that presents a challenging problem for surgeons. One-stage lengthening with an autologous bone graft has been preferred for metatarsals that require a limited lengthening. With a gradual lengthening of metatarsals, callus distraction (callotasis) can achieve a greater length gain and a concomitant lengthening of the soft tissue. This article presents results of callotasis for adults with first brachymetatarsia. The outcomes of nine cases of first brachymetatarsia in five adult patients who underwent metatarsal lengthening by callotasis between March 1999 and February 2005 were retrospectively reviewed and analyzed. The average length gain was 16.4 mm and the average lengthening percentage was 43.7%. In addition, the average healing index was calculated as 3.8 months/cm, which was higher than that reported previously in the fourth brachymetatarsia. It was concluded that the period of bony consolidation following callotasis is longer in the first brachymetatarsia than in the fourth brachymetatarsia. Presumably, this might be because of the anatomically larger osteotomized cut surface and its weight-bearing function.

  12. The diagnosis of stress fractures of runners by an isotope scintigraphy

    International Nuclear Information System (INIS)

    Karvonen, J.; Nieminen, M.

    1988-01-01

    By means of isotope scintigraphy the suspected stress fractures in the lower limb bones of ten competitive runners were verified in nine cases (9/10). In all cases the X-rays were normal. By conservative treatment avoiding excessive stress, the intensive local isotope uptake in the bone and pain symptoms of the stress fracture disappeared after 2-4 months. (orig.)

  13. Mechanisms Underlying Stress Fracture and the Influence of Sex and Race/Ethnicity

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-16-1-0652 TITLE: Mechanisms Underlying Stress Fracture and the Influence of Sex and Race/Ethnicity PRINCIPAL INVESTIGATOR...5a. CONTRACT NUMBER W81XWH-16-1-0652 Mechanisms Underlying Stress Fracture and the Influence of Sex and Race/Ethnicity 5b. GRANT NUMBER W81XWH...to stress fracture risk. In particular, in Study 1, we will perform advanced skeletal imaging along with gait-assessments in subjects with history of

  14. Acetabular roof stress fracture: a rare cause of hip pain in children ...

    African Journals Online (AJOL)

    Stress fracture of acetabular roof is an unusual cause of hip pain. It is considered as an underdiagnosed entity. People who are more susceptible to experience this fracture are athletes, soldiers and dancers. We present the case of an 11 year old girl with a roof acetabular stress fracture for which the diagnosis and ...

  15. Idiopathic Avascular Necrosis of First Metatarsal Head in a Pediatric Patient.

    Science.gov (United States)

    Kwon, Young-Uk; Choi, Jang-Seok; Kong, Gyu-Min; Ha, Byung-Ho

    Idiopathic avascular necrosis of the first metatarsal head rarely occurs in pediatrics. The present case of avascular necrosis of the first metatarsal head occurred in a 13-year-old male who came to the clinic with a 9-month history of pain in the first metatarsophalangeal joint. Conservative treatment had been applied for 9 months, but the pain had not been relieved. Therefore, surgical treatment, including decompression and debridement, was performed in the first metatarsal head of the patient. After 6 months of follow-up monitoring, full range of motion of the first metatarsophalangeal joint was observed, and the pain had disappeared. No any other complications had developed during 18 months of follow-up monitoring. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Investigations on the influence of the stress state on fracture-mechanical values

    International Nuclear Information System (INIS)

    Schmidt, P.

    1979-01-01

    Fracture toughness obtained from specimen can be applied to construction elements only when the same stress state exists. In standardised fracture-mechanical tests plain strain is realised. Using the stress intensity factor, a critical crack length or a critical load can be obtained. Above these values a crack propagates in an unstable way. The specimen are tested under uni-axial load. In this paper investigations have been made whether a biaxial load increases the stress state over the plain strain and whether consequently a decrease of the critical fracture toughness and a shift of the temperatures Tsub(g)sub(y) and Tsub(s) results which characterise the fracture behaviour of steel. In order to answer these questions the tests were made which induced due to their geometry an additional nominal stress parallel to the crack front in spite of uni-axial loading. The results were compared with those from specimen without an additional nominal stress and having in their cross section under same test conditions nearly the same plain strain. The fracture toughness of both specimen types were compared at temperatures between 142 K and 252 K and correlated to other material-characterising values. The tests were completed by stress analysis and by comparing the crack opening displacement. Due to the additional stress, Tsub(g)sub(y) was found to be 20 K higher than for the reference specimen. The fracture toughness decreases significantly in certain temperature ranges. The plastic stress concentration factor was comperatively higher and the remaining plastic crack opening decreases up to 25%. (orig.) [de

  17. Value of lateral blood pool imaging in patients with suspected stress fractures of the tibia.

    Science.gov (United States)

    Mohan, Hosahalli K; Clarke, Susan E M; Centenara, Martin; Lucarelli, Amanda; Baron, Daniel; Fogelman, Ignac

    2011-03-01

    To critically evaluate the use of lateral blood pool imaging in athletes with lower limb pain and with a clinical suspicion of stress fracture. Two experienced nuclear medicine physicians evaluated 3-phase bone scans using 99mTc-methylene diphosphonate performed in 50 consecutive patients referred from a specialist sports injury clinic for suspected tibial stress fracture. The vascularity to the tibia as seen on the blood pool (second phase) images in the anterior/posterior views was compared with the lateral/medial view assessments. Stress fractures were presumed to be present when on the delayed images (third phase) there was a focal or fusiform area of increased tracer uptake involving the tibial cortex. Shin splints which are a recognized cause of lower limb pain in athletes mimicking stress fracture were diagnosed if increased tracer uptake was seen extending along the posterior tibial surface with no significant focal or fusiform area of uptake within this. Inter-reviewer agreement for the assessment of vascularity was also assessed using Cohen's Kappa scores. Twenty-four stress fractures in 24 patients and 66 shin splints in 40 patients were diagnosed. In 18 patients stress fracture and shin splints coexisted. In 10 patients no tibial pathology was identified. Of the 24 patients diagnosed with stress fractures, lateral/medial blood pool imaging was superior in the assessment of blood pool activity (P tibial stress fractures, lateral views of the tibia provide the optimal method for evaluation of vascularity. Prospective studies with quantitative or semi-quantitative assessment of skeletal vascularity could provide supplementary information relating to the pathophysiology of stress fractures, for example, the time scale of vascular changes after a tibial stress fracture, and potentially could have clinical relevance as to the assessment of the severity of stress fractures and their prognosis.

  18. Chondromalacia of trochlear notch after healing of olecranon stress fracture: a case report.

    Science.gov (United States)

    Lu, Cheng-Chang; Chen, Shen-Kai; Wang, Chih-Wei; Chou, Pei-Hsi

    2006-05-01

    Chondromalacia of the trochlear notch and stress fracture of olecranon are uncommon injuries in the throwing athletes. We report an 18-year-old high school pitcher who had persistent postero-lateral elbow pain after a healed olecranon stress fracture of the right elbow. Diagnostic arthroscopy revealed chondromalacia of the trochlear notch. After treatment with arthroscopic drilling and abrasion chondroplasty, he returned to competitive pitching 1 year later postsurgery. This rare association between chondromalacia and stress fracture of the olecranon has not been reported previously in the literatures. Chondromalacia of the trochlear notch should be included as a differential diagnosis in evaluating athletes with persistent elbow pain after healed olecranon stress fractures.

  19. STRESS FRACTURE OF THE ULNA IN A BREAK-DANCER

    Directory of Open Access Journals (Sweden)

    Yu-Hsu Chen

    2008-12-01

    Full Text Available Break dancing is a popular activity in teenagers and is associated with severe trauma to bones and tissues. We report the first known case of a break dancer with an ulnar stress fracture. Such injuries occur in a variety of sports due to substantial stress on the ulna and repetitive excessive rotation of the forearm. In this study we describe a patient who experienced an ulnar stress fracture during break dancing training. The diagnosis was established by history and physical examination. Initial radiographic findings were negative. However, radiographs taken 3 months after initial presented revealed callus formation over the ulnar shaft. This suggested that readjustment is required in break dancing training protocols. It is important to increase awareness of this injury among physicians to expedite the diagnosis and to prevent the possibility of conversion to an overt fracture in the future

  20. Stress fractures of the rib arising from the manufactory assembly line

    International Nuclear Information System (INIS)

    Arima, Toru; Iwasaki, Masayuki

    2007-01-01

    We investigated stress injuries of the rib arising from the assembly line. The patients, all males, were 20 in number and divided into two groups; those with stress fracture (n=13) and those with ''pre-fracture'' (n=7). The former group with the average age of 37 years was involved by a single fracture in 10 patients and multiple fractures in 3, ranging from 5th to 8th ribs, with the affected side on the right in 9 and the left in 4. All 13 fractures occurred in the posterior half of the rib, in which 5 were located in its lateral portion, 5 in the middle, and 3 in the posterior. The latter group with the average age of 32 years were involved on the right side in 4 and the left in 3. The working pattern causing rib injuries was either repeated raising of the upper extremity or forward pushing of the shoulder girdle. The symptom was back pain, and aggravated especially in elevation of the arm, deep breathing and sneezing. Local tenderness over the fracture site was noted in all cases. X-ray findings at initial examination revealed fractures in most cases and 3D-CT was employed in 9 questionable cases to assess fracture conditions. In the ''pre-fracture'' group, although the fracture was not recognized on X-ray, the diagnosis was made as an impending fracture based on the localized tenderness on the rib. As to treatment, bust band fixation and work load reduction were performed. Stress fractures of the rib have been occasionally reported in sports medicine, but not so much in industrial medicine. This specific injury has been treated in literature as muscle strain because of the absence of apparent trauma. It is important to recognize the underlying pathology to make the correct diagnosis. In the early stage of rib fractures, 3D-CT was more useful than X-ray in making diagnosis and assessing the bony union. As to the pathomechanism of this condition, it was postulated that repeated raising or forward pushing of the arm applying excessive traction to the origin of the

  1. Epidemiology of stress fracture injuries among US high school athletes, 2005-2006 through 2012-2013.

    Science.gov (United States)

    Changstrom, Bradley G; Brou, Lina; Khodaee, Morteza; Braund, Cortney; Comstock, R Dawn

    2015-01-01

    High school athletes in the United States sustain millions of injuries annually, approximately 10% of which are fractures. However, there is no clear estimate of the number of stress fractures sustained by high school athletes annually despite reports that stress fractures account for 0.7% to 20% of injuries seen in sports medicine clinics. This suggests a high utilization of resources for a potentially preventable injury. In addition, stress fractures have been associated with low energy availability and disordered eating in young athletes, highlighting the importance of early recognition and intervention. To investigate stress fracture rates and patterns in a large national sample of US high school athletes. Descriptive epidemiologic study. Data from High School RIO (Reporting Information Online), a national sports injury surveillance study, were analyzed to describe rates and patterns of stress fracture injury sustained from 2005-2006 through 2012-2013, across sports and by sex. From 2005-2006 through 2012-2013, a total of 51,773 injuries were sustained during 25,268,873 athlete-exposures, of which 389 (0.8%) were stress fractures, resulting in an overall stress fracture rate of 1.54 per 100,000 athlete-exposures. Rates per 100,000 athlete-exposures were highest in girls' cross country (10.62), girls' gymnastics (7.43), and boys' cross country (5.42). In sex-comparable sports, girls sustained more stress fractures (63.3%) than did boys (36.7%) and had higher rates of stress fracture (2.22 vs 1.27; rate ratio, 1.75; 95% CI, 1.38-2.23). The most commonly injured sites were the lower leg (40.3% of all stress fractures), foot (34.9%), and lower back/lumbar spine/pelvis (15.2%). Management was nonsurgical in 98.7% of the cases, and 65.3% of injuries resulted in ≥3 weeks of time loss, medical disqualification, or an end to the season before athletes could return to play. Although a rare injury, stress fractures cause considerable morbidity for high school athletes

  2. Association of stressful life events with incident falls and fractures in older men: the Osteoporotic Fractures in Men (MrOS) Study

    Science.gov (United States)

    Fink, Howard A.; Kuskowski, Michael A.; Marshall, Lynn M.

    2014-01-01

    Background: small, retrospective studies suggest that major life events and/or sudden emotional stress may increase fall and fracture risk. The current study examines these associations prospectively. Methods: a total of 5,152 men aged ≥65 years in the Osteoporotic Fractures in Men study self-reported data on stressful life events for 1 year prior to study Visit 2. Incident falls and fractures were ascertained for 1 year after Visit 2. Fractures were centrally confirmed. Results: a total of 2,932 (56.9%) men reported ≥1 type of stressful life event. In men with complete stressful life event, fall and covariate data (n = 3,949), any stressful life event was associated with a 33% increased risk of incident fall [relative risk (RR) 1.33, 95% confidence interval (CI) 1.19–1.49] and 68% increased risk of multiple falls (RR = 1.68, 95% CI = 1.40–2.01) in the year following Visit 2 after adjustment for age, education, Parkinson's disease, diabetes, stroke, instrumental activities of daily living (IADL) impairment, chair stand time, walk speed, multiple past falls, depressive symptoms and antidepressant use. Risk increased with the number of types of stressful life events. Though any stressful life event was associated with a 58% increased age-adjusted risk for incident fracture, this association was attenuated and no longer statistically significant after additional adjustment for total hip bone mineral density, fracture after age 50, Parkinson's disease, stroke and IADL impairment. Conclusions: in this cohort of older men, stressful life events significantly increased risk of incident falls independent of other explanatory variables, but did not independently increase incident fracture risk. PMID:24002237

  3. Quantitative analysis of scintigraphic findings in tibial stress fractures in Thoroughbred racehorses.

    Science.gov (United States)

    Valdés-Martínez, Alejandro; Seiler, Gabriela; Mai, Wilfried; Bolt, David M; Mudge, Margaret; Dukti, Sarah A; Hubert, Jeremy D

    2008-07-01

    To develop a quantitative method of interpreting tibial scintigrams of Thoroughbred racehorses with tibial stress fractures that may facilitate diagnosis of fractures and to provide prognostic information regarding future performance of affected horses. 35 Thoroughbred racehorses. Static bone-phase scintigrams of tibial stress fractures were quantitatively analyzed by use of ratios of the mean radionuclide counts per pixel in a region of interest (ROI) drawn around the area of increased uptake of radiopharmaceutical to mean counts per pixel in a second ROI drawn around an apparently normal area of the tibial diaphysis. In horses with unilateral fractures, ratios for the contralateral tibia were determined by use of 2 ROIs drawn at the same positions as the ROIs in the fractured tibia. Ratios were compared between fractured versus apparently normal tibias, between horses that returned to racing versus those that did not, and among horses with various grades of lameness. The association between ratios for fractured tibias and intervals between diagnosis and return to racing was also assessed. Mean ratio of ROIs in apparently normal tibias was 1.35 (95% confidence interval [CI], 1.21 to 1.50); that in tibias with stress fractures was 3.55 (95% CI, 2.50 to 4.60). These ratios were significantly different. None of the associations between ratios for fractured tibias and grades of lameness or performance outcomes were significant. Tibial stress fracture scintigrams can be quantitatively analyzed. A prospective study with a controlled rehabilitation period is necessary to evaluate the possible applications of this method.

  4. Bone lesions from overload: shin splint and stress fracture

    International Nuclear Information System (INIS)

    Una Gorospe; Jon Andoni; Isla Gallego, Concepcion; Santana Borbones, Aranzazu; Perera Romero, Carmen; Allende Riera, Ana J

    2005-01-01

    There are many stress injuries in the lower extremities due to exercise, and the case we present is an example of two injuries which may present in children or young adults who train excessively. The patient complains of pain and tightness on exercise. The underlying pathology is probably rupture of insertion fibres of the tibial and soleus (Sharpey's fibres) muscles. Probably, there is also periostitis and myositis. Stress fractures and shin splints are often present at the same time in different stages, and both are typical pathologies due to excessive training. Scintigraphy allows identification and early management of shin splints and stress fractures (au)

  5. Surgical treatment of refractory tibial stress fractures in elite dancers: a case series.

    Science.gov (United States)

    Miyamoto, Ryan G; Dhotar, Herman S; Rose, Donald J; Egol, Kenneth

    2009-06-01

    Treatment of tibial stress fractures in elite dancers is centered on rest and activity modification. Surgical intervention in refractory cases has important implications affecting the dancers' careers. Refractory tibial stress fractures in dancers can be treated successfully with drilling and bone grafting or intramedullary nailing. Case series; Level of evidence, 4. Between 1992 and 2006, 1757 dancers were evaluated at a dance medicine clinic; 24 dancers (1.4%) had 31 tibial stress fractures. Of that subset, 7 (29.2%) elite dancers with 8 tibial stress fractures were treated operatively with either intramedullary nailing or drilling and bone grafting. Six of the patients were followed up closely until they were able to return to dance. One patient was available only for follow-up phone interview. Data concerning their preoperative treatment regimens, operative procedures, clinical union, radiographic union, and time until return to dance were recorded and analyzed. The mean age of the surgical patients at the time of stress fracture was 22.6 years. The mean duration of preoperative symptoms before surgical intervention was 25.8 months. Four of the dancers were male and 3 were female. All had failed nonoperative treatment regimens. Five patients (5 tibias) underwent drilling and bone grafting of the lesion, and 2 patients (3 tibias) with completed fractures or multiple refractory stress fractures underwent intramedullary nailing. Clinical union was achieved at a mean of 6 weeks and radiographic union at 5.1 months. Return to full dance activity was at an average of 6.5 months postoperatively. Surgical intervention for tibial stress fractures in dancers who have not responded to nonoperative management allowed for resolution of symptoms and return to dancing with minimal morbidity.

  6. Case report 491: Stress fracture of the right sacrum

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, T.A.; Nguyen, T.H.; Daffner, R.H.; Lupetin, A.R.; Deeb, Z.L.

    1988-07-01

    A case of stress fracture of the right sacrum in a postpartum woman has been presented. Key features in making the diagnosis include a history of pain in the sacrum, considerable weight gain during the pregnancy and pronounced increased physical activity in the immediate postpartum period. CT, particularly, and MRI were critical in making the diagnosis. A low signal area on the T-1 neglected image was considered characteristic for the sacral fracture. In the CT studies a vertical lucency thru a zone of sclerosis is classical for a fracture, whether an insufficiency fracture or a fatigue fracture.

  7. Talar body fatigue stress fractures: three cases observed in elite female gymnasts

    International Nuclear Information System (INIS)

    Rossi, F.; Dragoni, S.

    2005-01-01

    To introduce and emphasize the clinical and radiological findings of three talar body fatigue stress fractures in competitive athletes. Clinical and radiographic skeletal records of 24,562 athletes taken between 1962 and 2002 were retrospectively reviewed. Among these, 6851 files related to acute foot and ankle injuries or chronic post-traumatic sequelae were found. There were 925 (3.76%) stress fatigue fractures selected from the whole collection. Among these there were three cases (0.32%) of talar body stress fractures diagnosed in elite female gymnasts 15 - 17 years old. The negative first radiograph become positive 4-6 weeks later. Scintigraphy was positive at an early stage and consistent for the diagnosis. CT and MRI gave positive results 1-2 weeks after the beginning of symptoms which were always greatly diagnostic. The sports medicine literature lacks reports of talar body fatigue stress fractures. The poor initial sensitivity of radiography makes it problematic to establish an early diagnosis. A wise combination of scintigraphy, CT and MRI has therefore to be relied upon. Familiarity with this rare location for a stress fracture may prevent delayed diagnosis and long-lasting damage, both of which are important factors in competitive athletes. (orig.)

  8. Talar body fatigue stress fractures: three cases observed in elite female gymnasts

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, F. [National Institute of Sports Medicine of the Italian Olympic Committee, Rome (Italy); Dragoni, S. [National Institute of Sports Medicine of the Italian Olympic Committee, Rome (Italy); Istituto Nazionale di Medicina dello Sport, Rome (Italy)

    2005-07-01

    To introduce and emphasize the clinical and radiological findings of three talar body fatigue stress fractures in competitive athletes. Clinical and radiographic skeletal records of 24,562 athletes taken between 1962 and 2002 were retrospectively reviewed. Among these, 6851 files related to acute foot and ankle injuries or chronic post-traumatic sequelae were found. There were 925 (3.76%) stress fatigue fractures selected from the whole collection. Among these there were three cases (0.32%) of talar body stress fractures diagnosed in elite female gymnasts 15 - 17 years old. The negative first radiograph become positive 4-6 weeks later. Scintigraphy was positive at an early stage and consistent for the diagnosis. CT and MRI gave positive results 1-2 weeks after the beginning of symptoms which were always greatly diagnostic. The sports medicine literature lacks reports of talar body fatigue stress fractures. The poor initial sensitivity of radiography makes it problematic to establish an early diagnosis. A wise combination of scintigraphy, CT and MRI has therefore to be relied upon. Familiarity with this rare location for a stress fracture may prevent delayed diagnosis and long-lasting damage, both of which are important factors in competitive athletes. (orig.)

  9. Identification of natural fractures and in situ stress at Rantau Dedap geothermal field

    Science.gov (United States)

    Artyanto, Andika; Sapiie, Benyamin; Idham Abdullah, Chalid; Permana Sidik, Ridwan

    2017-12-01

    Rantau Dedap Area is a geothermal field which is located in Great Sumatra Fault (GSF). The fault and fracture are main factor in the permeability of the geothermal system. However, not all faults and fractures have capability of to flow the fluids. Borehole image log is depiction of the borehole conditions, it is used to identify the natural fractures and drilling induced fracture. Both of them are used to identify the direction of the fracture, direction of maximum horizontal stress (SHmax), and geomechanics parameters. The natural fractures are the results of responses to stress on a rock and permeability which controlling factor in research area. Breakouts is found in this field as a trace of drilling induced fracture due to in situ stress work. Natural fractures are strongly clustered with true strike trending which first, second, and third major direction are N170°E - N180°E (N-S), N60°E - N70°E (NE-SW), and N310°E - N320°E (NW-SE), while the dominant dip is 80° -90°. Based on borehole breakout analysis, maximum horizontal stress orientation is identified in N162°E - N204°E (N-S) and N242°E (NE-SW) direction. It’s constantly similar with regional stress which is affected by GSF. Several parameters have been identified and analyzed are SHmax, SHmin, and Sy. It can be concluded that Rantau Dedap Geothermal Field is affected by strike-slip regime. The determination of in situ stress and natural fractures are important to study the pattern of permeability which is related to the fault in reservoir of this field.

  10. Radiographic evaluation for AVN following distal metatarsal Stoffella bunion osteotomy.

    Science.gov (United States)

    Klein, Christian; Zembsch, Alexander; Dorn, Ulrich

    2009-01-01

    Avascular necrosis of the metatarsal head, delayed bone healing and nonunion are complications that may occur after distal first metatarsal osteotomies. Intraoperative damage to the extraosseous blood supply, the location of the osteotomy and postoperative vasospasm have been cited as possible causes of such changes. We evaluated Stoffella's subcapital osteotomies which were performed at our department for the correction of moderate to severe hallux valgus deformities. Standardized radiographs of 300 feet, taken 6weeks, 3 months, and 6 months postoperatively and at the final followup were examined with regard to postoperative AVN or signs of delayed bone healing. Of 228 patients, 202 were women and 26 were men. The patients' mean age was 49 years, and the mean followup was 12 months. In 278 cases the radiographs revealed an unremarkable first metatarsal head. Seventeen cases showed diffuse or localized osteopenia or small cysts in the subchondral bone. These changes fully resolved on subsequent radiographs. The X-rays of two patients revealed progressive narrowing of the joint space, irregular contours on the surface of the joint and an abnormal bone structure. The patients subsequently developed a characteristic picture of avascular necrosis, in one case combined with nonunion. Three patients had delayed bone healing, but ultimately healed successfully. Ischemic changes in bone are known to occur after distal first metatarsal osteotomies. There is a very low incidence of postoperative perfusion problems after Stoffella;s technique, even with lateral soft tissue release.

  11. Femoral neck stress fractures (fnsf) in military recruits

    International Nuclear Information System (INIS)

    Majeed, N.U.; Naqvi, A.N.; Majeed, H.

    2012-01-01

    Objective: To identify patterns of Femoral Neck Stress Fractures (FNSF), its presentation and outcome of its treatment in PMA (Pakistan Military Academy) cadets. These findings would help suggest guidelines for their appropriate management. Study design: Case Series Place and duration of study: CMH Abbottabad and CMH Rawalpindi from May 2005 to January 2008. Materials and Methods: Twenty cases (20 hips in 18 patients) of FNSF were included in the study. Only male cadets from Pakistan Military Academy (PMA) were included. Diagnosis was made clinically and was confirmed by radiographs or bone scan. Incomplete fractures were managed conservatively where as complete fractures were fixed surgically. Results: All compression fractures healed conservatively where as tension fractures needed surgical fixation in all the cases, except one where fracture remained incomplete. Rest of tension fractures converted from incomplete fractures to complete fractures and hence needed surgical stabilization. There was no problem of avascular necrosis of femoral head (AVNFH) in any patient. Conclusion: FNSF are uncommon injuries with potentially serious complications and are difficult to diagnose clinically. When diagnosed early and managed appropriately, they carry good prognosis. (author)

  12. Stress fracture of the second proximal phalanx of the foot in teenage athletes: Unrecognized location of stress fracture

    Directory of Open Access Journals (Sweden)

    Satoshi Yamaguchi

    2017-10-01

    Conclusion: Although a rare injury, it is important that clinicians be aware of this type of stress fracture, as a timely diagnosis can avoid the need for surgical treatment and allow an early return to play.

  13. Fracture permeability under effect of normal and shear stress: A preliminary experimental investigation

    International Nuclear Information System (INIS)

    Mohanty, S.; Manteufel, R.D.; Chowdhury, A.H.

    1995-01-01

    The change in fracture permeability under mechanical loads have been investigated. An apparatus has been developed to measure change in fracture permeability, when a single fracture is subjected to normal and shear stress. Both radial and linear flow experiments have been conducted by modifying a direct shear test apparatus. Preliminary results suggest a 35-percent change in fracture permeability under normal stress to 8 MPa and nearly 350 percent under shear displacement of 9.9254 m (1 in.) at 5 MPa normal stress. Effort is underway to separate the permeability change due to gouge material production from that of due to dilation

  14. Radiological findings and healing patterns of incomplete stress fractures of the pars interarticularis

    International Nuclear Information System (INIS)

    Dunn, Andrew J.; Campbell, Robert S.D.; Mayor, Peter E.; Rees, Dai

    2008-01-01

    The objective was to retrospectively record the CT and MRI features and healing patterns of acute, incomplete stress fractures of the pars interarticularis. The CT scans of 156 adolescents referred with suspected pars interarticularis stress fractures were reviewed. Patients with incomplete (grade 2) pars fractures were included in the study. Fractures were assessed on CT according to vertebral level, location of cortical involvement and direction of fracture propagation. MRI was also performed in 72 of the 156 cases. MRI images of incomplete fractures were assessed for the presence of marrow oedema and cortical integrity. Fracture healing patterns were characterised on follow-up CT imaging. Twenty-five incomplete fractures were identified in 23 patients on CT. All fractures involved the inferior or infero-medial cortex of the pars and propagated superiorly or superolaterally. Ninety-two percent of incomplete fractures demonstrated either complete or partial healing on follow-up imaging. Two (8%) cases progressed to complete fractures. Thirteen incomplete fractures in 11 patients confirmed on CT also had MRI, and 92% demonstrated oedema in the pars. Ten out of thirteen fractures (77%) showed a break in the infero-medial cortex with intact supero-lateral cortex, which correlated with the CT findings. MRI incorrectly graded one case as a complete (grade 3) fracture, and 2 cases as (grade 1) stress reaction. Six fractures had follow-up MRI, 67% showed partial or complete cortical healing, and the same number showed persistent marrow oedema. Incomplete fracture of the pars interarticularis represents a stage of the evolution of a complete stress fracture. The direction of fracture propagation is consistent, and complete healing can be achieved in most cases with appropriate clinical management. CT best demonstrates fracture size and extent, and is the most appropriate modality for follow-up. MRI is limited in its ability to fully depict the cortical integrity of

  15. Radiological findings and healing patterns of incomplete stress fractures of the pars interarticularis

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, Andrew J.; Campbell, Robert S.D. [Royal Liverpool and Broadgreen University Teaching Hospitals, Department of Medical Imaging, Liverpool (United Kingdom); Mayor, Peter E. [Leighton Hospital, Department of Medical Imaging, Crewe, Cheshire (United Kingdom); Rees, Dai [Robert Jones and Agnes-Hunt Orthopaedic Hospital, Department of Orthopaedic Surgery, Oswestry, Shropshire (United Kingdom)

    2008-05-15

    The objective was to retrospectively record the CT and MRI features and healing patterns of acute, incomplete stress fractures of the pars interarticularis. The CT scans of 156 adolescents referred with suspected pars interarticularis stress fractures were reviewed. Patients with incomplete (grade 2) pars fractures were included in the study. Fractures were assessed on CT according to vertebral level, location of cortical involvement and direction of fracture propagation. MRI was also performed in 72 of the 156 cases. MRI images of incomplete fractures were assessed for the presence of marrow oedema and cortical integrity. Fracture healing patterns were characterised on follow-up CT imaging. Twenty-five incomplete fractures were identified in 23 patients on CT. All fractures involved the inferior or infero-medial cortex of the pars and propagated superiorly or superolaterally. Ninety-two percent of incomplete fractures demonstrated either complete or partial healing on follow-up imaging. Two (8%) cases progressed to complete fractures. Thirteen incomplete fractures in 11 patients confirmed on CT also had MRI, and 92% demonstrated oedema in the pars. Ten out of thirteen fractures (77%) showed a break in the infero-medial cortex with intact supero-lateral cortex, which correlated with the CT findings. MRI incorrectly graded one case as a complete (grade 3) fracture, and 2 cases as (grade 1) stress reaction. Six fractures had follow-up MRI, 67% showed partial or complete cortical healing, and the same number showed persistent marrow oedema. Incomplete fracture of the pars interarticularis represents a stage of the evolution of a complete stress fracture. The direction of fracture propagation is consistent, and complete healing can be achieved in most cases with appropriate clinical management. CT best demonstrates fracture size and extent, and is the most appropriate modality for follow-up. MRI is limited in its ability to fully depict the cortical integrity of

  16. Longitudinal stress fracture: patterns of edema and the importance of the nutrient foramen

    Energy Technology Data Exchange (ETDEWEB)

    Craig, Joseph G.; Widman, David; Holsbeeck, Marnix van [Department of Radiology, Henry Ford Hospital, Detroit, MI 48202 (United States)

    2003-01-01

    We reviewed the MR appearances of six cases of longitudinal stress fracture of the lower extremity.Results. One fracture was in the femur and five were in the tibia. Four of the tibial fractures showed edema starting in the mid-tibia at the level of the nutrient foramen with the fracture on the anteromedial cortex. The other tibial fracture started at the nutrient foramen. Three fractures (two tibial and the femur fracture) showed eccentric marrow edema; all fractures showed either eccentric periosteal reaction or soft tissue edema.Conclusion. Primary diagnosis of longitudinal stress fracture is made by finding a vertical cleft on one or more axial images. Secondary signs of position of the nutrient foramen and patterns of edema may be useful. (orig.)

  17. Distinct hip and rearfoot kinematics in female runners with a history of tibial stress fracture.

    Science.gov (United States)

    Milner, Clare E; Hamill, Joseph; Davis, Irene S

    2010-02-01

    Cross-sectional controlled laboratory study. To investigate the kinematics of the hip, knee, and rearfoot in the frontal and transverse planes in female distance runners with a history of tibial stress fracture. Tibial stress fractures are a common overuse injury in runners, accounting for up to half of all stress fractures. Abnormal kinematics of the lower extremity may contribute to abnormal musculoskeletal load distributions, leading to an increased risk of stress fractures. Thirty female runners with a history of tibial stress fracture were compared to 30 age-matched and weekly-running-distance-matched control subjects with no previous lower extremity bony injuries. Kinematic and kinetic data were collected using a motion capture system and a force platform, respectively, as subjects ran in the laboratory. Selected variables of interest were compared between the groups using a multivariate analysis of variance (MANOVA). Peak hip adduction and peak rearfoot eversion angles were greater in the stress fracture group compared to the control group. Peak knee adduction and knee internal rotation angles and all joint angles at impact peak were similar between the groups. Runners with a previous tibial stress fracture exhibited greater peak hip adduction and rearfoot eversion angles during the stance phase of running compared to healthy controls. A consequence of these mechanics may be altered load distribution within the lower extremity, predisposing individuals to stress fracture.

  18. A new coal-permeability model: Internal swelling stress and fracture-matrix interaction

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.H.; Rutqvist, J.

    2009-10-01

    We have developed a new coal-permeability model for uniaxial strain and constant confining stress conditions. The model is unique in that it explicitly considers fracture-matrix interaction during coal deformation processes and is based on a newly proposed internal-swelling stress concept. This concept is used to account for the impact of matrix swelling (or shrinkage) on fracture-aperture changes resulting from partial separation of matrix blocks by fractures that do not completely cut through the whole matrix. The proposed permeability model is evaluated with data from three Valencia Canyon coalbed wells in the San Juan Basin, where increased permeability has been observed during CH{sub 4} gas production, as well as with published data from laboratory tests. Model results are generally in good agreement with observed permeability changes. The importance of fracture-matrix interaction in determining coal permeability, demonstrated in this work using relatively simple stress conditions, underscores the need for a dual-continuum (fracture and matrix) mechanical approach to rigorously capture coal-deformation processes under complex stress conditions, as well as the coupled flow and transport processes in coal seams.

  19. Medial supracondylar stress fracture in an adolescent pitcher

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Eric Y.; Chung, Christine B. [VA San Diego Healthcare System, San Diego, CA (United States); University of California, San Diego Medical Center, San Diego, CA (United States); Fronek, Jan [Scripps Healthcare, La Jolla, CA (United States)

    2014-01-15

    We report the occurrence of a medial supracondylar stress fracture in an adolescent pitcher. To our knowledge, this fracture has not been described in the literature, and awareness of this entity allows initiation of therapy and precludes further unnecessary work-up. The radiographic, computed tomography, and magnetic resonance imaging appearances are reviewed and the mechanism of injury is discussed. (orig.)

  20. Preventive osteopathic manipulative treatment and stress fracture incidence among collegiate cross-country athletes.

    Science.gov (United States)

    Brumm, Lynn F; Janiski, Carrie; Balawender, Jenifer L; Feinstein, Adam

    2013-12-01

    Stress fractures are common among athletes, particularly distance runners, with many theories regarding the etiologic process of stress fractures and various studies identifying risk factors or suggesting preventive techniques. To our knowledge, no previous studies have discussed the possible causative effects of somatic dysfunction or the preventive capabilities of osteopathic manipulative treatment (OMT). To apply a preventive OMT protocol for cross-country athletes to reduce the incidence of stress fractures. Cohort study. Examinations of cross-country athletes at an NCAA (National Collegiate Athletic Association) Division I university were performed by supervising physician-examiners and first- and second-year osteopathic medical students during several consecutive academic years. Athletes re-enrolled in the study each year they continued to be eligible. The intervention included osteopathic structural examination and OMT that focused on somatic dysfunction identified in the pelvis, sacrum, and lower extremities. More than 1800 participant examinations were performed on 124 male and female participants by 3 supervising physician-examiners and 141 osteopathic medical students over the course of 5 consecutive academic years (2004-2005 to 2008-2009). Data from these academic years were compared with data from the previous 8 academic years (1996-1997 to 2003-2004). An average of 20 new participants enrolled yearly. The number of annual stress fractures per team ranged from 0 to 6 for male participants and 1 to 6 for female participants. The cumulative annual incidence of stress fractures for male participants demonstrated a statistically significant decrease from 13.9% (20 of 144) before intervention to 1.0% (1 of 105) after intervention, resulting in a 98.7% relative reduction in stress-fracture diagnosis (P=.019). The cumulative annual incidence for female participants showed a minimal decrease from 12.9% (23 of 178) before intervention to 12.0% (17 of 142) after

  1. The reliability of dual-energy X-ray absorptiometry measurements of bone mineral density in the metatarsals

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Joel T.; Buckley, Jonathan D.; Tsiros, Margarita D.; Thewlis, Dominic [University of South Australia, Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research, GPO Box 2471, Adelaide, South Australia (Australia); Archer, Jane [University of South Australia, Medical Radiation, School of Health Sciences, Adelaide (Australia)

    2016-01-15

    To investigate the reliability of a simple, efficient technique for measuring bone mineral density (BMD) in the metatarsals using dual-energy X-ray absorptiometry (DXA). BMD of the right foot of 32 trained male distance runners was measured using a DXA scanner with the foot in the plantar position. Separate regions of interest (ROI) were used to assess the BMD of each metatarsal shaft (1st-5th) for each participant. ROI analysis was repeated by the same investigator to determine within-scan intra-rater reliability and by a different investigator to determine within-scan inter-rater reliability. Repeat DXA scans were undertaken for ten participants to assess between-scan intra-rater reliability. Assessment of BMD was consistently most reliable for the first metatarsal across all domains of reliability assessed (intra-class correlation coefficient [ICC] ≥0.97; coefficient of variation [CV] ≤1.5 %; limits of agreement [LOA] ≤4.2 %). Reasonable levels of intra-rater reliability were also achieved for the second and fifth metatarsals (ICC ≥0.90; CV ≤4.2 %; LOA ≤11.9 %). Poorer levels of reliability were demonstrated for the third (ICC ≥0.64; CV ≤8.2 %; LOA ≤23.6 %) and fourth metatarsals (ICC ≥0.67; CV ≤9.6 %; LOA ≤27.5 %). BMD was greatest in the first and second metatarsals (P < 0.01). Reliable measurements of BMD were achieved for the first, second and fifth metatarsals. (orig.)

  2. The reliability of dual-energy X-ray absorptiometry measurements of bone mineral density in the metatarsals

    International Nuclear Information System (INIS)

    Fuller, Joel T.; Buckley, Jonathan D.; Tsiros, Margarita D.; Thewlis, Dominic; Archer, Jane

    2016-01-01

    To investigate the reliability of a simple, efficient technique for measuring bone mineral density (BMD) in the metatarsals using dual-energy X-ray absorptiometry (DXA). BMD of the right foot of 32 trained male distance runners was measured using a DXA scanner with the foot in the plantar position. Separate regions of interest (ROI) were used to assess the BMD of each metatarsal shaft (1st-5th) for each participant. ROI analysis was repeated by the same investigator to determine within-scan intra-rater reliability and by a different investigator to determine within-scan inter-rater reliability. Repeat DXA scans were undertaken for ten participants to assess between-scan intra-rater reliability. Assessment of BMD was consistently most reliable for the first metatarsal across all domains of reliability assessed (intra-class correlation coefficient [ICC] ≥0.97; coefficient of variation [CV] ≤1.5 %; limits of agreement [LOA] ≤4.2 %). Reasonable levels of intra-rater reliability were also achieved for the second and fifth metatarsals (ICC ≥0.90; CV ≤4.2 %; LOA ≤11.9 %). Poorer levels of reliability were demonstrated for the third (ICC ≥0.64; CV ≤8.2 %; LOA ≤23.6 %) and fourth metatarsals (ICC ≥0.67; CV ≤9.6 %; LOA ≤27.5 %). BMD was greatest in the first and second metatarsals (P < 0.01). Reliable measurements of BMD were achieved for the first, second and fifth metatarsals. (orig.)

  3. The reliability of dual-energy X-ray absorptiometry measurements of bone mineral density in the metatarsals.

    Science.gov (United States)

    Fuller, Joel T; Archer, Jane; Buckley, Jonathan D; Tsiros, Margarita D; Thewlis, Dominic

    2016-01-01

    To investigate the reliability of a simple, efficient technique for measuring bone mineral density (BMD) in the metatarsals using dual-energy X-ray absorptiometry (DXA). BMD of the right foot of 32 trained male distance runners was measured using a DXA scanner with the foot in the plantar position. Separate regions of interest (ROI) were used to assess the BMD of each metatarsal shaft (1st-5th) for each participant. ROI analysis was repeated by the same investigator to determine within-scan intra-rater reliability and by a different investigator to determine within-scan inter-rater reliability. Repeat DXA scans were undertaken for ten participants to assess between-scan intra-rater reliability. Assessment of BMD was consistently most reliable for the first metatarsal across all domains of reliability assessed (intra-class correlation coefficient [ICC] ≥0.97; coefficient of variation [CV] ≤1.5%; limits of agreement [LOA] ≤4.2%). Reasonable levels of intra-rater reliability were also achieved for the second and fifth metatarsals (ICC ≥0.90; CV ≤4.2%; LOA ≤11.9%). Poorer levels of reliability were demonstrated for the third (ICC ≥0.64; CV ≤8.2%; LOA ≤23.6%) and fourth metatarsals (ICC ≥0.67; CV ≤9.6%; LOA ≤27.5%). BMD was greatest in the first and second metatarsals (P Reliable measurements of BMD were achieved for the first, second and fifth metatarsals.

  4. Diagnosis, treatment, and rehabilitation of stress fractures in the lower extremity in runners

    OpenAIRE

    Kahanov, Leamor; Eberman,Lindsey; Games,Kenneth; Wasik,Mitch

    2015-01-01

    Leamor Kahanov,1 Lindsey E Eberman,2 Kenneth E Games,2 Mitch Wasik2 1College of Health Science, Misericordia University, Dallas, PA, USA; 2Department of Applied Medicine and Rehabilitation, Indiana State University, Terre Haute, IN, USA Abstract: Stress fractures account for between 1% and 20% of athletic injuries, with 80% of stress fractures in the lower extremity. Stress fractures of the lower extremity are common injuries among individuals who participate in endurance, high load-bearing ...

  5. Sequential Proximal Tibial Stress Fractures associated with Prolonged usage of Methotrexate and Corticosteroids: A Case Report

    Directory of Open Access Journals (Sweden)

    Tan TJL

    2015-11-01

    Full Text Available Stress fractures of the proximal tibia metaphysis are rare in the elderly. We present a case of a 65-year old male who developed sequential proximal tibia stress fractures associated with prolonged usage of methotrexate and prednisolone within a span of 18 months. Magnetic Resonance Imaging revealed an incomplete stress fracture involving the medial proximal tibial region. The patient was treated with stemmed total knee arthroplasty (TKA bilaterally. Stress fractures should be considered in patients with atypical knee pain who have a history of methotrexate and prednisolone usage. TKA is an effective treatment in stress fractures of the proximal tibia.

  6. Distribution and natural history of stress fractures in U.S. Marine recruits

    International Nuclear Information System (INIS)

    Greaney, R.B.; Gerber, F.H.; Laughlin, R.L.; Kmet, J.P.; Metz, C.D.; Kilcheski, T.S.; Rao, B.R.; Silverman, E.D.

    1983-01-01

    In a prospective study of stress injuries of the lower extremities of U.S. Marine recruits, researchers derived a frequency distribution of stress fractures. The most frequently fractured bone was the tibia (73%), while the single most common site was the posterior calcaneal tuberosity (21%). The natural history of stress fractures by scintigraphy and radiography has been outlined, showing the evolutionary changes on either study as a universal progression independent of injury site or type of stress. An identical spectrum of changes should be present within any group undergoing intense new exercise. The frequency distribution of stress fractures should be a function of differing forms and intensities of exercise, therefore, our figures should not be applied to other groups. Researchers used the presence of a scintigraphic abnormality at a symptomatic site as the criterion for diagnosis of stress fracture. Since the distribution of skeletal radiotracer uptake is directly dependent on local metabolic activity, it is expected that a focal alteration in bone metabolism will result in a scintigram approaching 100% sensitivity for the abnormality (9). In the proper clinical setting, the specificity should approximate this figure; however, a focal, nonstress-related bone abnormality which has not manifested any radiographic change, such as early osteomyelitis, could result in a false-positive examination. Specificity cannot, therefore, be accurately determined without an actual determination of the pathologic changes within the bone, necessarily involving biopsy

  7. Direct Imaging of Natural Fractures and Stress Compartments Stimulated by Hydraulic Fracturing

    Science.gov (United States)

    Lacazette, A.; Vermilye, J. M.

    2014-12-01

    This contribution will present results from passive seismic studies of hydraulic fracture treatments in North American and Asian basins. One of the key data types is a comparatively new surface-based seismic imaging product - "Tomographic Fracture Images®" (TFI®). The procedure is an extension of Seismic Emission Tomography (SET), which is well-established and widely used. Conventional microseismic results - microearthquake hypocenter locations, magnitudes, and focal mechanism solutions - are also obtained from the data via a branch of the processing workflow. TFI is accomplished by summing the individual time steps in a multidimensional SET hypervolume over extended periods of time, such as an entire frac stage. The dimensions of a SET hypervolume are the X, Y, and Z coordinates of the voxels, the time step (typically on the order of 100 milliseconds), and the seismic activity value. The resulting summed volume is skeletonized to produce images of the main fracture surfaces, which are known to occupy the maximum activity surfaces of the high activity clouds from theory, field studies, and experiments. The orientation vs. area of the resulting TFIs can be analyzed in detail and compared with independent data sets such as volumetric structural attributes from reflection seismic data and borehole fracture data. We find that the primary effect of hydraulic fracturing is to stimulate preexisting natural fracture networks and faults. The combination of TFIs with hypocenter distributions and microearthquake focal mechanisms provides detailed information on subsurface stress compartmentalization. Faults are directly imaged which allows discrimination of fault planes from auxiliary planes of focal mechanism solutions. Examples that will be shown include simultaneous movement on a thrust fault and tear fault and examples of radically different stress compartments (e.g. extensional vs. wrench faulting) stimulated during a single hydraulic fracture treatment. The figure

  8. Stress fractures in athletes. How to spot this underdiagnosed injury.

    Science.gov (United States)

    Sallis, R E; Jones, K

    1991-05-01

    Stress fractures are an increasingly common injury in competitive athletes, especially runners. Amenorrheic athletes are at particularly high risk. A radionuclide bone scan should be considered when the index of suspicion for stress fracture is high. Plain radiographs are of little use in establishing the diagnosis in the early stages of the injury. Early diagnosis and prompt institution of conservative therapy allow for a favorable outcome in most cases. Avoidance of or reduced participation in the inciting activity is important for pain control. Certain stress fractures, such as those involving the femoral neck, should be monitored closely and treated aggressively with internal fixation when conservative measures fail. Runners who have exercise-induced amenorrhea should be advised to decrease their training intensity to a level where menses resume. Cyclic therapy with conjugated estrogens and progesterone should also be considered, as should daily calcium supplementation.

  9. Sport related stress fracture of the clavicle with non-union: Case report and review

    Science.gov (United States)

    Constantinou, Demitri; Kastanos, Konstantinos

    2008-01-01

    Stress fractures are relatively uncommon sports injuries and when they do occur, are mostly found in the lower limb. Stress fractures of the clavicle are particularly rare, having been described in a number of non-sport related pathologies, such as nervous tics and post radical neck dissection. In sport, there have only been seven cases reported in the literature. We report on a clavicle stress fracture in a 47-year-old male, partaking in recreational weight lifting activities. This is the first reported case of a non-union stress fracture of the clavicle. The patient underwent an open reduction and internal fixation and made a full recovery. PMID:21264151

  10. Bilateral Tibial Stress Fractures in a Young Man Associated with Idiopathic Osteoporosis - Case Report

    Directory of Open Access Journals (Sweden)

    Selahattin Özyürek

    2010-12-01

    Full Text Available Stress fractures are defined as a partial or complete fracture of bone due to an inability to endure a non-violent stress. Two factors have been proposed to explain the aetiology of stress fractures: muscle fatigue, and direct muscle action. We want to point to third factor with our case report: Osteoporosis. (From the World of Osteoporosis 2010;16:58-60

  11. Prediction of retained residual stresses in laboratory fracture mechanics specimens extracted from welded components

    International Nuclear Information System (INIS)

    Hurlston, R.G.; Sherry, A.H.; James, P.; Sharples, J.K.

    2015-01-01

    The measurement of weld material fracture toughness properties is important for the structural integrity assessment of engineering components. However, welds can contain high levels of residual stress and these can be retained in fracture mechanics specimens, particularly when machined from non-stress relieved welds. Retained residual stresses can make the measurement of valid fracture toughness properties difficult. This paper describes the results of analytical work undertaken to investigate factors that can influence the magnitude and distribution of residual stresses retained in fracture mechanics specimen blanks extracted from as-welded ferritic and austenitic stainless steel plates. The results indicate that significant levels of residual stress can be retained in specimen blanks prior to notching, and that the magnitude and distribution of stress is dependent upon material properties, specimen geometry and size, and extraction location through the thickness of the weld. Finite element modelling is shown to provide a useful approach for estimating the level and distributions of retained residual stresses. A new stress partitioning approach has been developed to estimate retained stress levels and results compare favourably with FE analysis and available experimental data. The approach can help guide the selection of specimen geometry and machining strategies to minimise the level of residual stresses retained in fracture mechanics specimen blanks extracted from non stress-relieved welds and thus improve the measurement of weld fracture toughness properties. - Highlights: • A simplified method for generating realistic weld residual stresses has been developed. • It has been shown that significant levels of residual stress can be retained within laboratory fracture mechanics specimens. • The level and distribution is dependant upon material, specimen type, specimen size and extraction location. • A method has been developed to allow estimates of the

  12. STRESS FRACTURE OF THE FIRST RIB IN A HIGH SCHOOL WEIGHT LIFTER

    Directory of Open Access Journals (Sweden)

    Hiroyuki Fujioka

    2009-06-01

    Full Text Available A 17-year-old boy, who played a weight lifting in high school, sustained stress fracture of the first rib without any causes. We successfully treated first rib stress fracture with limitation of using the upper extremity and with using low-intensity pulsed ultrasound

  13. First Metatarsal Proximal Opening Wedge Osteotomy for Correction of Hallux Valgus Deformity: Comparison of Straight versus Oblique Osteotomy

    Science.gov (United States)

    Han, Seung Hwan; Park, Eui Hyun; Jo, Joon; Koh, Yong Gon; Lee, Jin Woo; Choi, Woo Jin

    2015-01-01

    Purpose The aim of this study was to compare clinical and radiographic outcomes of proximal opening wedge osteotomy using a straight versus oblique osteotomy. Materials and Methods We retrospectively reviewed 104 consecutive first metatarsal proximal opening wedge osteotomies performed in 95 patients with hallux valgus deformity. Twenty-six feet were treated using straight metatarsal osteotomy (group A), whereas 78 feet were treated using oblique metatarsal osteotomy (group B). The hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle, and distance from the first to the second metatarsal (distance) were measured for radiographic evaluation, whereas the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score was used for clinical evaluation. Results Significant corrections in the HVA, IMA, and distance from the first to the second metatarsal were obtained in both groups at the last follow-up (p<0.001). There was no difference in the mean IMA correction between the 2 groups (6.1±2.7° in group A and 6.0±2.1° in group B). However, a greater correction in the HVA and distance from the first to the second metatarsal were found in group B (HVA, 13.2±8.2°; distance, 25.1±0.2 mm) compared to group A (HVA, 20.9±7.7°; distance, 28.1±0.3 mm; p<0.001). AOFAS scores were improved in both groups. However, group B demonstrated a greater improvement relative to group A (p=0.005). Conclusion Compared with a straight first metatarsal osteotomy, an oblique first metatarsal osteotomy yielded better clinical and radiological outcomes. PMID:25837181

  14. Lateral Sesamoid Position Relative to the Second Metatarsal in Feet With and Without Hallux Valgus: A Prospective Study.

    Science.gov (United States)

    Geng, Xiang; Zhang, Chao; Ma, Xin; Wang, Xu; Huang, Jiazhang; Xu, Jian; Wang, Chen

    2016-01-01

    We sought to determine whether hallux valgus displaces the sesamoid bones laterally away from a stationary first metatarsal or whether the first metatarsal head is displaced medially from the stationary sesamoids, which remain in position relative to the rest of the forefoot. We reviewed weightbearing radiographs in the dorsal plantar view of 128 consecutive patients (149 feet) seen over 2 months in 2014. Of these, 82 feet (55%) had a hallux valgus angle of >15° (hallux valgus group) and 67 feet (45%) had an angle of no more than 15° (control group). We measured the absolute distances from the center of the lateral sesamoid and the first metatarsal head to the long axis of the second metatarsal. Next, the relative distances, defined as the ratio of these 2 absolute distances to the length of the second metatarsal, were calculated to adjust for foot size. Both the absolute and the relative distances from the center of the first metatarsal head to the second metatarsal differed significantly between the 2 groups and correlated positively with the hallux valgus angle and first intermetatarsal angle. However, neither the absolute nor the relative distance to the lateral sesamoid bone differed significantly between the groups, nor did they correlate with either of the 2 angles. Thus, despite medial shifting of the first metatarsal in hallux valgus, the lateral sesamoid retains its relationship to the second metatarsal in transverse plane. Its apparent lateral movement is a radiographic misinterpretation. Awareness of this misinterpretation should improve the success of corrective surgery. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Case 24: Stress Fracture of the Tibia

    Science.gov (United States)

    2008-03-01

    Disease, Osteomalacia, Osteogenesis Imperfecta , pelvic irradiation, corticosteroid therapy, Rhematoid Arthritis. Patients present with a history of...sacrum, pubic ramus, calcaneous, navicular, or metatarsal bones. They usually results from a change in exercise status (ie: increased running...new exercise program. Often, patients complain of nocturnal pain that makes sleeping difficult. On physical exam the overlying skin is often normal

  16. STAFAN, Fluid Flow, Mechanical Stress in Fractured Rock of Nuclear Waste Repository

    International Nuclear Information System (INIS)

    Huyakorn, P.; Golis, M.J.

    1989-01-01

    1 - Description of program or function: STAFAN (Stress And Flow Analysis) is a two-dimensional, finite-element code designed to model fluid flow and the interaction of fluid pressure and mechanical stresses in a fractured rock surrounding a nuclear waste repository. STAFAN considers flow behavior of a deformable fractured system with fracture-porous matrix interactions, the coupling effects of fluid pressure and mechanical stresses in a medium containing discrete joints, and the inelastic response of the individual joints of the rock mass subject to the combined fluid pressure and mechanical loading. 2 - Restrictions on the complexity of the problem: STAFAN does not presently contain thermal coupling, and it is unable to simulate inelastic deformation of the rock mass and variably saturated or two-phase flow in the fractured porous medium system

  17. Anterior tibial stress fractures treated with anterior tension band plating in high-performance athletes.

    Science.gov (United States)

    Cruz, Alexandre Santa; de Hollanda, João Paris Buarque; Duarte, Aires; Hungria Neto, José Soares

    2013-06-01

    The non-surgical treatment of anterior tibial cortex stress fractures requires long periods of abstention from sports activities and often results in non-union. Many different surgical techniques have already been previously described to treat these fractures, but there is no consensus on the best treatment. We describe the outcome of treatment using anterior tibial tension band plating in three high-performance athletes (4 legs) with anterior tibial cortex stress fractures. Tibial osteosynthesis with a 3.5-mm locking compression plate in the anterolateral aspect of the tibia was performed in all patients diagnosed with anterior tibial stress fracture after September 2010 at Santa Casa Hospital. All of the fractures were consolidated within a period of 3 months after surgery, allowing for an early return to pre-injury levels of competitive sports activity. There were no infection, non-union, malunion or anterior knee pain complications. Anterior tibial tension band plating leads to prompt fracture consolidation and is a good alternative for the treatment of anterior tibial cortex stress fractures. Bone grafts were shown to be unnecessary.

  18. Avascular necrosis of the epiphysis of the first metatarsal bone

    Energy Technology Data Exchange (ETDEWEB)

    Souverijns, G.; Peene, P.; Cleeren, P. [Department of Radiology, Virga Jesse Hospital, Hasselt (Belgium); Raes, M. [Department of Pediatrics, Virga Jesse Hospital, Hasselt (Belgium); Steenwerckx, A. [Department of Orthopaedics, Virga Jesse Hospital, Hasselt (Belgium)

    2002-06-01

    We report a case of avascular necrosis of the epiphysis of the right first metatarsal in a 6-year-old boy. Radiographs showed sclerosis, collapse and a crescent sign in the epiphysis. The diagnosis was confirmed by magnetic resonance imaging and scintigraphy. Arch support was the therapy of choice. Six months after the onset of symptoms, a definite reossification was present. To our knowledge, this is the first radiological report of avascular necrosis of the epiphysis of the first metatarsal bone in the world literature, which prompted a review of the osteochondroses and their etiology. (orig.)

  19. Avascular necrosis of the epiphysis of the first metatarsal bone

    International Nuclear Information System (INIS)

    Souverijns, G.; Peene, P.; Cleeren, P.; Raes, M.; Steenwerckx, A.

    2002-01-01

    We report a case of avascular necrosis of the epiphysis of the right first metatarsal in a 6-year-old boy. Radiographs showed sclerosis, collapse and a crescent sign in the epiphysis. The diagnosis was confirmed by magnetic resonance imaging and scintigraphy. Arch support was the therapy of choice. Six months after the onset of symptoms, a definite reossification was present. To our knowledge, this is the first radiological report of avascular necrosis of the epiphysis of the first metatarsal bone in the world literature, which prompted a review of the osteochondroses and their etiology. (orig.)

  20. Bipartite hallucal sesamoid bones: relationship with hallux valgus and metatarsal index

    Energy Technology Data Exchange (ETDEWEB)

    Munuera, Pedro V.; Dominguez, Gabriel [University of Seville, Department of Podiatrics, Seville (Spain); Centro Docente de Fisioterapia y Podologia, Departamento de Podologia, Seville (Spain); Reina, Maria; Trujillo, Piedad [Centro Docente de Fisioterapia y Podologia, Departamento de Podologia, Seville (Spain)

    2007-11-15

    The objective was to relate the incidence of the partition of the hallucal sesamoid bones to the size of the first metatarsal and the hallux valgus deformity. In a sample of 474 radiographs, the frequency of appearance of bipartite sesamoids was studied. The length and relative protrusion of the first metatarsal, and the hallux abductus angle, were measured and compared between the feet with and without sesamoid partition. The results showed that 14.6% of the feet studied had at least one partite sesamoid, that the sesamoid most frequently divided was the medial, and that unilateral partition was the most common. No difference was found in the incidence of partite sesamoids between men and women, or between left and right feet. Protrusion and length of the first metatarsal are greater in feet with partite sesamoids than in feet without this condition. A significantly higher incidence of bipartite medial sesamoid was obtained in feet with hallux valgus compared with normal feet. (orig.)

  1. Bipartite hallucal sesamoid bones: relationship with hallux valgus and metatarsal index

    International Nuclear Information System (INIS)

    Munuera, Pedro V.; Dominguez, Gabriel; Reina, Maria; Trujillo, Piedad

    2007-01-01

    The objective was to relate the incidence of the partition of the hallucal sesamoid bones to the size of the first metatarsal and the hallux valgus deformity. In a sample of 474 radiographs, the frequency of appearance of bipartite sesamoids was studied. The length and relative protrusion of the first metatarsal, and the hallux abductus angle, were measured and compared between the feet with and without sesamoid partition. The results showed that 14.6% of the feet studied had at least one partite sesamoid, that the sesamoid most frequently divided was the medial, and that unilateral partition was the most common. No difference was found in the incidence of partite sesamoids between men and women, or between left and right feet. Protrusion and length of the first metatarsal are greater in feet with partite sesamoids than in feet without this condition. A significantly higher incidence of bipartite medial sesamoid was obtained in feet with hallux valgus compared with normal feet. (orig.)

  2. Bilateral stress fracture of femoral neck in non-athlete - case report

    Directory of Open Access Journals (Sweden)

    Ubiratan Stefani de Oliveira

    Full Text Available ABSTRACT Bilateral stress fracture of femoral neck in healthy young patients is an extremely rare entity, whose diagnostic and treatment represent a major challenge. Patients with history of hip pain, even non-athletes or military recruits, should be analyzed to achieve an early diagnosis and prevent possible complications from the surgical treatment. This report describes a 43-year-old male patient, non-athlete, without previous diseases, who developed bilateral stress fracture of femoral neck without displacement. He had a late diagnosis; bilateral osteosynthesis was made using cannulated screws. Although the diagnosis was delayed in this case, the study highlights the importance of the diagnosis of stress fracture, regardless of the activity level of the patients, for the success of the treatment.

  3. The effects of the local fracture stress and carbides on the cleavage fracture characteristics of Mn-Mo-Ni low alloy steels in the transition region

    International Nuclear Information System (INIS)

    Yang, Won Jon; Huh, Moo Young; Roh, Sung Joo; Lee, Bong Sang; Oh, Yong Jun; Hong, Jun Hwa

    2000-01-01

    In the ductile-brittle transition temperature region of SA508 C1.3 Mn-Mo-Ni low alloy steels, the relationship of the local fracture stress and carbides influencing the cleavage fracture behavior was investigated. Based on the ASTM E1921-97 standard method, the reference transition temperatures were determined by three point bending fracture toughness tests. A local fracture stress σ f * , was determined from a theoretical stress distribution in front of crack tip using the cleavage initiation distance measured in each fractured specimen surface. The local fracture stress values showed a strong relationship with toughness characteristics of the materials and those were larger in the materials of smaller carbide size. Quantitative analysis of carbides showed that carbides larger than a certain size are mainly responsible for the cleavage fracture in the ductile-brittle transition temperature region. (author)

  4. Longitudinal stress fracture of the femur: A rare presentation

    International Nuclear Information System (INIS)

    Bilreiro, Carlos; Bahia, Carla; Castro, Miguel Oliveira e

    2016-01-01

    We present the case of an 80 year old woman with hip pain, caused by a longitudinal femoral insufficiency stress fracture, depicted with radiographs, CT and MR. This type of fracture is very rare, with only a few cases reported. We conducted a literature review and compared the findings with the present case

  5. Review of possible correlations between in situ stress and PFL fracture transmissivity data at Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Derek (University of Alberta (United States)); Follin, Sven (SF GeoLogic AB (Sweden))

    2011-11-15

    In laboratory samples, the fracture transmissivity decreases significantly as the confining stress increases. While these experimental relationships are widely accepted and validated on laboratory samples, it is unknown if such relationships exist in situ or if these relationships can be scaled from the centimetre-scale laboratory tests to the metre-scale of in situ fractures. The purpose of this work is to assess the relationship between the structural-hydraulic data gathered in deep, cored boreholes at Forsmark and the in situ stress state acting on the these fractures. In conclusion, there does not appear to be sufficient evidence from these analyses to support the notion that the magnitude of the flow along the fractures at Forsmark is solely controlled by the in situ stress acting on the fracture. This should not be surprising because the majority of the fractures formed more than 1 billion years ago and the current in situ stress state has only been active for the past 12 million years. It is more likely that the transmissivity values are controlled by fracture roughness, open channels within the fracture, fracture stiffness and fracture infilling material

  6. Stress fracture and premenstrual syndrome in Japanese adolescent athletes: a cross-sectional study.

    Science.gov (United States)

    Takeda, Takashi; Imoto, Yoko; Nagasawa, Hiroyo; Takeshita, Atsuko; Shiina, Masami

    2016-10-18

    To investigate the relationship between the occurrence of stress fracture and premenstrual syndrome (PMS)/premenstrual dysphoric disorder (PMDD) in Japanese adolescent athletes. Cross-sectional study. Osaka, Japan. A school-based survey on menstruation and school life was conducted using a sample of 1818 Japanese female students who belonged to two public high schools in Japan. Among them, we recruited 394 athletes who had regular menstrual cycles (25-38 days) and completed a questionnaire about their premenstrual symptoms and their competitive career. Premenstrual symptoms and the occurrence of stress fracture. The prevalences of moderate-to-severe PMS and PMDD were 8.9% and 1.3%, respectively, which were the same as in collegiate athletes in a previous study. Premenstrual symptoms disturbed 'Work efficiency or productivity, home responsibilities', 'Relationships with coworkers or family' and 'Athletic performance in training or competition' more severely than menstrual pain (p=0.031, p=0.004 and p<0.001, respectively). 66 athletes (16.8%) reported having experienced a stress fracture. The severity of 'Overeating or food cravings', 'Physical symptoms' and 'Performance in training or competition' in athletes with previous stress fractures were much higher than in those without a history of stress fractures (p=0.015, p=0.008 and p=0.006, respectively). In terms of premenstrual symptoms, 'Physical symptoms' was associated with an increased risk of stress fractures in athletes (OR 1.66, 95% CI 1.06 to 2.62). The results from this study indicated that premenstrual symptoms may affect athletic performance and has the risk of stress fractures in adolescent athletes. 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/.

  7. L5 radiculopathy due to sacral stress fracture

    International Nuclear Information System (INIS)

    Aylwin, Anthony; Saifuddin, Asif; Tucker, Stuart

    2003-01-01

    We report the case of a 70-year-old man who presented with a history of left buttock pain with radiation into the left leg in an L5 distribution. MRI of the lumbar spine revealed a left sacral stress fracture with periosteal reaction involving the left L5 nerve root anterior to the sacral ala. With spontaneous healing of the fracture, the patient's symptoms resolved completely. (orig.)

  8. Outcomes of Surgical Treatment for Anterior Tibial Stress Fractures in Athletes: A Systematic Review.

    Science.gov (United States)

    Chaudhry, Zaira S; Raikin, Steven M; Harwood, Marc I; Bishop, Meghan E; Ciccotti, Michael G; Hammoud, Sommer

    2017-12-01

    Although most anterior tibial stress fractures heal with nonoperative treatment, some may require surgical management. To our knowledge, no systematic review has been conducted regarding surgical treatment strategies for the management of chronic anterior tibial stress fractures from which general conclusions can be drawn regarding optimal treatment in high-performance athletes. This systematic review was conducted to evaluate the surgical outcomes of anterior tibial stress fractures in high-performance athletes. Systematic review; Level of evidence, 4. In February 2017, a systematic review of the PubMed, MEDLINE, Cochrane, SPORTDiscus, and CINAHL databases was performed to identify studies that reported surgical outcomes for anterior tibial stress fractures. Articles meeting the inclusion criteria were screened, and reported outcome measures were documented. A total of 12 studies, published between 1984 and 2015, reporting outcomes for the surgical treatment of anterior tibial stress fractures were included in this review. All studies were retrospective case series. Collectively, surgical outcomes for 115 patients (74 males; 41 females) with 123 fractures were evaluated in this review. The overall mean follow-up was 23.3 months. The most common surgical treatment method reported in the literature was compression plating (n = 52) followed by drilling (n = 33). Symptom resolution was achieved in 108 of 123 surgically treated fractures (87.8%). There were 32 reports of complications, resulting in an overall complication rate of 27.8%. Subsequent tibial fractures were reported in 8 patients (7.0%). Moreover, a total of 17 patients (14.8%) underwent a subsequent procedure after their initial surgery. Following surgical treatment for anterior tibial stress fracture, 94.7% of patients were able to return to sports. The available literature indicates that surgical treatment of anterior tibial stress fractures is associated with a high rate of symptom resolution and return

  9. Couple stresses and the fracture of rock.

    Science.gov (United States)

    Atkinson, Colin; Coman, Ciprian D; Aldazabal, Javier

    2015-03-28

    An assessment is made here of the role played by the micropolar continuum theory on the cracked Brazilian disc test used for determining rock fracture toughness. By analytically solving the corresponding mixed boundary-value problems and employing singular-perturbation arguments, we provide closed-form expressions for the energy release rate and the corresponding stress-intensity factors for both mode I and mode II loading. These theoretical results are augmented by a set of fracture toughness experiments on both sandstone and marble rocks. It is further shown that the morphology of the fracturing process in our centrally pre-cracked circular samples correlates very well with discrete element simulations. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  10. Radiographic features that enable assessment of first metatarsal rotation: the role of pronation in hallux valgus

    Energy Technology Data Exchange (ETDEWEB)

    Eustace, S. (Dept. of Radiology, Mater Misericordiae Hospital, Dublin (Ireland)); O' Byrne, J. (Dept. of Orthopaedics, Mater Misericordiae Hospital, Dublin (Ireland)); Stack, J. (Dept. of Radiology, Mater Misericordiae Hospital, Dublin (Ireland)); Stephens, M.M. (Dept. of Orthopaedics, Mater Misericordiae Hospital, Dublin (Ireland))

    1993-04-01

    This study describes a method of detecting first metatarsal pronation on the basis of the movement of the inferior tuberosity of the base of 20 cadaveric first metatarsals at 0 , 10 , 20 and 30 pronation. On pronation, the inferior tuberosity of the base of the first metatarsal moved lateral to the mid-line axis. At 10 , the tuberosity pointed to the junction of the inner third and outer two-thirds of a line between the midpoint and lateral tubercle of the base. At 20 , it pointed to the junction of the inner two-thirds and outer third of that line. At 30 , it pointed to the outer marting of the lateral third. Using these features, the amount of first metatarsal pronation in 100 consecutive weigth-bearing views of feet was recorded and plotted against the corresponding intermetatarsal angles in those feet. Four of 43 patients with an intermetatarsal angle of less than 9 had pronation greater than 10 , 48 of 57 patients with an intermetatarsal angle greater than 9 had pronation greater than 10 (P<0.001). As intermetatarsal angles increase, the amount of first metatarsal pronation increases (r=0.69). Pronation and varus deviation of the first metatarsal are linked; both alter the tendon balance maintaining proximal phalanx alignment and lead to the development of hallux valgus. (orig.)

  11. Radiographic features that enable assessment of first metatarsal rotation: the role of pronation in hallux valgus

    International Nuclear Information System (INIS)

    Eustace, S.; O'Byrne, J.; Stack, J.; Stephens, M.M.

    1993-01-01

    This study describes a method of detecting first metatarsal pronation on the basis of the movement of the inferior tuberosity of the base of 20 cadaveric first metatarsals at 0 , 10 , 20 and 30 pronation. On pronation, the inferior tuberosity of the base of the first metatarsal moved lateral to the mid-line axis. At 10 , the tuberosity pointed to the junction of the inner third and outer two-thirds of a line between the midpoint and lateral tubercle of the base. At 20 , it pointed to the junction of the inner two-thirds and outer third of that line. At 30 , it pointed to the outer marting of the lateral third. Using these features, the amount of first metatarsal pronation in 100 consecutive weigth-bearing views of feet was recorded and plotted against the corresponding intermetatarsal angles in those feet. Four of 43 patients with an intermetatarsal angle of less than 9 had pronation greater than 10 , 48 of 57 patients with an intermetatarsal angle greater than 9 had pronation greater than 10 (P<0.001). As intermetatarsal angles increase, the amount of first metatarsal pronation increases (r=0.69). Pronation and varus deviation of the first metatarsal are linked; both alter the tendon balance maintaining proximal phalanx alignment and lead to the development of hallux valgus. (orig.)

  12. Rehabilitation and return to running after lower limb stress fractures.

    Science.gov (United States)

    Liem, Brian C; Truswell, Hallie J; Harrast, Mark A

    2013-01-01

    Lower limb stress fractures are common injuries in runners. In terms of treatment, much of the medical literature has focused primarily on rest and cessation of running, but little has been written about the rehabilitation and functional progression of runners following a lower limb stress fracture. This article reviews the scientific evidence behind common rehabilitation concepts used for runners recovering from these injuries and also discusses sport-specific training modalities such as deep water running and antigravity treadmill training. Overall this article is intended to be a practical resource for clinicians to guide runners in functional rehabilitation and return to running following lower limb stress injury.

  13. Stress fractures of the ribs and upper extremities: causation, evaluation, and management.

    Science.gov (United States)

    Miller, Timothy L; Harris, Joshua D; Kaeding, Christopher C

    2013-08-01

    Stress fractures are common troublesome injuries in athletes and non-athletes. Historically, stress fractures have been thought to predominate in the lower extremities secondary to the repetitive stresses of impact loading. Stress injuries of the ribs and upper extremities are much less common and often unrecognized. Consequently, these injuries are often omitted from the differential diagnosis of rib or upper extremity pain. Given the infrequency of this diagnosis, few case reports or case series have reported on their precipitating activities and common locations. Appropriate evaluation for these injuries requires a thorough history and physical examination. Radiographs may be negative early, requiring bone scintigraphy or MRI to confirm the diagnosis. Nonoperative and operative treatment recommendations are made based on location, injury classification, and causative activity. An understanding of the most common locations of upper extremity stress fractures and their associated causative activities is essential for prompt diagnosis and optimal treatment.

  14. Subtrochanteric stress fractures in patients on oral bisphosphonate therapy: an emerging problem.

    LENUS (Irish Health Repository)

    Murphy, Colin G

    2012-01-31

    The emergence of a new variant of subtrochanteric stress fractures of the femur, affecting patients on oral bisphosphonate therapy, has only recently been described. This fracture is often preceded by pain and distinctive radiographic changes (lateral cortical thickening), and associated with a characteristic fracture pattern (transverse fracture line and medial cortical spike). A retrospective review (2007-2009) was carried out for patients who were taking oral bisphosphonates and who sustained a subtrochanteric fracture after a low velocity injury. Eleven fractures were found in 10 patients matching the inclusion criteria outlined. All were females, and taking bisphosphonates for a mean of 43 years. Five of the 10 patients mentioned prodromal symptoms, for an average of 9.4 months before the fracture. Although all fractures were deemed low velocity, 5 of 11 were even atraumatic. Two patients had previously sustained contralateral subtrochanteric fractures. Plain radiographs of two patients showed lateral cortical thickening on the contralateral unfractured femur; the bisphosphonate therapy was stopped and close surveillance was started. Patients taking oral bisphosphonates may be at risk of a new variant of stress fracture of the proximal femur. Awareness of the symptoms is the key to ensure that appropriate investigations are undertaken.

  15. Short-term effects of teriparatide versus placebo on bone biomarkers, structure, and fracture healing in women with lower-extremity stress fractures: A pilot study

    Directory of Open Access Journals (Sweden)

    Ellen A. Almirol

    2016-09-01

    Conclusions: In this randomized, pilot study, brief administration of TPTD showed anabolic effects that TPTD may help hasten fracture healing in premenopausal women with lower-extremity stress fractures. Larger prospective studies are warranted to determine the effects of TPTD treatment on stress fracture healing in premenopausal women.

  16. Implications of recent developments in the plastic fracture mechanics field to the PCI stress corrosion problem

    International Nuclear Information System (INIS)

    Smith, E.

    1980-01-01

    Fractographic observations on irradiated Zircaloy cladding stress corrosion fracture surfaces are considered against the background of recent developments in the plastic fracture mechanics field. Dimples have been observed on the fracture surfaces of failed cladding, even though the cracks in metallographic sections are tight, i.e., crack propagation is associated with a low crack tip opening angle. This result is interpreted as providing evidence for an environmentally assisted ductile mode of fracture. The presence of this fracture mode forms the basis of an argument, which adds further support for the view that power ramp stress corrosion cladding failures are caused by stress concentrations that produce stress gradients in the cladding. (orig.)

  17. Estimation of body mass index from the metrics of the first metatarsal

    Science.gov (United States)

    Dunn, Tyler E.

    ideas of biomechanical bone remodeling; the elements of the skeleton that are under higher forces, including weight, will remodel to minimize stress. A commonly used metric for the mechanical method of body mass estimation is the diameter of the head of the femur. The foot experiences nearly the entire weight force of the individual at any point in the gait cycle and is subject to the biomechanical remodeling that this force would induce. Therefore, the application of the mechanical framework for body mass estimation could stand true for the elements of the foot. The morphometric and mechanical approaches have been validated against one another on a large, geographically disparate population (Auerbach and Ruff, 2004), but have yet to be validated on a sample of known body mass. DeGroote and Humphrey (2011) test the ability of the first metatarsal to estimate femoral head diameter, body mass, and femoral length. The estimated femoral head diameter from the first metatarsal is used to estimate body mass via the morphometric approach and the femoral length is used to estimate living stature. The authors find that body mass and stature estimation methods from more commonly used skeletal elements compared well with the methods developed from the first metatarsal. This study examines 388 `White' individuals from the William M. Bass donated skeletal collection to test the reliability of the body mass estimates from femoral head diameter and bi-iliac breadth, stature from maximum femoral length, and body mass and stature from the metrics of the first metatarsal. This sample included individuals from all four of the BMI classes. This study finds that all of the skeletal indicators compare well with one another; there is no statistical difference in the stature estimates from the first metatarsal and the maximum length of the femur, and there is no statistical between all three of the body mass estimation methods. When compared to the forensic estimates of stature neither of the

  18. Immediate effects of modified landing pattern on a probabilistic tibial stress fracture model in runners.

    Science.gov (United States)

    Chen, T L; An, W W; Chan, Z Y S; Au, I P H; Zhang, Z H; Cheung, R T H

    2016-03-01

    Tibial stress fracture is a common injury in runners. This condition has been associated with increased impact loading. Since vertical loading rates are related to the landing pattern, many heelstrike runners attempt to modify their footfalls for a lower risk of tibial stress fracture. Such effect of modified landing pattern remains unknown. This study examined the immediate effects of landing pattern modification on the probability of tibial stress fracture. Fourteen experienced heelstrike runners ran on an instrumented treadmill and they were given augmented feedback for landing pattern switch. We measured their running kinematics and kinetics during different landing patterns. Ankle joint contact force and peak tibial strains were estimated using computational models. We used an established mathematical model to determine the effect of landing pattern on stress fracture probability. Heelstrike runners experienced greater impact loading immediately after landing pattern switch (Ptibial strains and the risk of tibial stress fracture in runners with different landing patterns (P>0.986). Immediate transitioning of the landing pattern in heelstrike runners may not offer timely protection against tibial stress fracture, despite a reduction of impact loading. Long-term effects of landing pattern switch remains unknown. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Spontaneous osteonecrosis of the knee associated with tibial plateau and femoral condyle insufficiency stress fracture

    Energy Technology Data Exchange (ETDEWEB)

    Narvaez, J.A.; Narvaez, J.; Lama, E.De; Sanchez, A. [Department of Magnetic Resonance Imaging, IDI Hospital Duran i Reynals, Ciutat Sanitaria i Universitaria de Bellvitge, Gran Via s/n, 08907, L' Hospitalet de Llobregat (Barcelona) (Spain)

    2003-08-01

    The purpose of this article is to describe the association between spontaneous osteonecrosis and insufficiency stress fractures of the knee. To determine whether insufficiency stress fracture is associated with spontaneous osteonecrosis of the knee, we retrospectively reviewed the medical charts and imaging studies of all patients with spontaneous osteonecrosis of the knee, studied by MR imaging, seen in a tertiary hospital over an 8-year period. Four women (age range 66-84 years) presented spontaneous osteonecrosis of the knee associated with insufficiency stress fracture of the medial tibial plateau. One of these patients also presented a concomitant insufficiency stress fracture of the medial femoral condyle. Radiographs were diagnostic of spontaneous osteonecrosis of the medial femoral condyle in three cases, and insufficiency stress fracture of the medial tibial plateau was detected in one case. Magnetic resonance imaging allows the diagnosis of both conditions in all four cases. Spontaneous osteonecrosis of the knee may be associated with insufficiency stress fracture of the medial femoral condyle and the medial tibial plateau. This association provides additional arguments in favor of the traumatic etiology of spontaneous osteonecrosis of knee. (orig.)

  20. Spontaneous osteonecrosis of the knee associated with tibial plateau and femoral condyle insufficiency stress fracture

    International Nuclear Information System (INIS)

    Narvaez, J.A.; Narvaez, J.; Lama, E.De; Sanchez, A.

    2003-01-01

    The purpose of this article is to describe the association between spontaneous osteonecrosis and insufficiency stress fractures of the knee. To determine whether insufficiency stress fracture is associated with spontaneous osteonecrosis of the knee, we retrospectively reviewed the medical charts and imaging studies of all patients with spontaneous osteonecrosis of the knee, studied by MR imaging, seen in a tertiary hospital over an 8-year period. Four women (age range 66-84 years) presented spontaneous osteonecrosis of the knee associated with insufficiency stress fracture of the medial tibial plateau. One of these patients also presented a concomitant insufficiency stress fracture of the medial femoral condyle. Radiographs were diagnostic of spontaneous osteonecrosis of the medial femoral condyle in three cases, and insufficiency stress fracture of the medial tibial plateau was detected in one case. Magnetic resonance imaging allows the diagnosis of both conditions in all four cases. Spontaneous osteonecrosis of the knee may be associated with insufficiency stress fracture of the medial femoral condyle and the medial tibial plateau. This association provides additional arguments in favor of the traumatic etiology of spontaneous osteonecrosis of knee. (orig.)

  1. Stress fractures of the humerus, radius, and tibia in horses: clinical features and radiographic and/or scintigraphic appearance

    International Nuclear Information System (INIS)

    Mackey, V.S.; Trout, D.R.; Meagher, D.M.; Hornof, W.J.

    1987-01-01

    The medical records, radiographic and nuclear scintigraphic findings of 26 racing horses with 27 stress fracture episodes of the humerus, radius, or tibia were reviewed. The purposes of this study were to describe the radiographic and/or scintigraphic features of stress fractures of the humerus, radius, or tibia, and to evaluate the signalment and history of horses in which stress fracture occurred. Stress fractures of the three long bones examined were primarily seen in 2- and 3-year-old male Thoroughbred horses; commonly, the onset of lameness was immediately following training gallops or racing. There were 13 humeral stress fracture episodes in 12 horses. Ten were in the proximal caudolateral cortex, and three were in the distal craniomedial cortex. Radical stress fractures were seen in three horses, all in the midshaft radius. Tibial stress fractures were diagnosed in 11 horses. They were located in the proximal lateral tibia in six horses, the distal caudolateral tibia in three horses, and the midshaft tibia in three horses. Fifteen stress fractures were diagnosed with radiography alone, one was diagnosed with scintigraphy alone, nine were diagnosed with radiographs and scintigraphy, and, in two horses, radiographs were negative, but the scintigraphic findings were consistent with stress fracture

  2. Stress and gas hydrate-filled fracture distribution, Krishna-Godavari Basin, India

    Energy Technology Data Exchange (ETDEWEB)

    Cook, A.; Goldberg, D. [Lamont-Doherty Earth Observatory of Columbia Univ., Palisades, NY (United States)

    2008-07-01

    The first expedition of the Indian National Gas Hydrate Program (NGHP) was launched in the summer of 2006 to characterize the presence of gas hydrates on the continental margins of India. This paper presented a study from the NGHP expedition that found high resistivity fractures in unconsolidated clay sediments on logging-while-drilling (LWD) borehole resistivity images. Gas hydrate-filled and conductive fractures appearing on LWD resistivity images in holes 5A, 5B, 6A, 7A and 10 were analysed and discussed. Fracture orientation and shallow sediment stress orientations were determined for each hole. The paper described how to determine which sections of a log are hydrate bearing as well as how to calculate the predicted water saturated resistivity. It was concluded that holes 5A, 5B, 6A and 7A contained well-ordered, high-angle fractures, from which horizontal stress directions could be accurately resolved. However, these stress directions, contradicted the orientations normally seen on a passive margin, and may be the result of local bathymetry variations. 6 refs., 1 tab., 11 figs.

  3. Photoelastic stress analysis assisted evaluation of fracture toughness in hydrothermally aged epoxies

    Directory of Open Access Journals (Sweden)

    G. Pitarresi

    2014-10-01

    Full Text Available The present work has investigated the fracture toughness of a model DGEBA epoxy system subject to Hidro-Thermal aging. A Photoelastic Stress Analysis technique has been implemented, showing the evolution of stresses arising throughout the water uptake process due to the non-uniform swelling of the material. Gravimetric and Dynamic Mechanical Thermal Analyses have further complemented the characterization, showing the onset of plasticization effects with aging. The correlation of all previous characterizations has allowed to conclude that an increase of KIC fracture toughness is obtained at the fully saturated condition. In particular Photoelasticity has also revealed the onset of relevant swelling induced stresses during the first stages of water absorption, leading to an increase of fracture toughness due to compressive stresses settling near the crack tip. A stress free condition is instead reestablished at the later stages of absorption, suggesting that the increased toughness of the saturated material is an effect of the modifications induced by aging on the polymer structure.

  4. Case report: multifocal subchondral stress fractures of the femoral heads and tibial condyles in a young military recruit.

    Science.gov (United States)

    Yoon, Pil Whan; Yoo, Jeong Joon; Yoon, Kang Sup; Kim, Hee Joong

    2012-03-01

    Subchondral stress fractures of the femoral head may be either of the insufficiency-type with poor quality bone or the fatigue-type with normal quality bone but subject to high repetitive stresses. Unlike osteonecrosis, multiple site involvement rarely has been reported for subchondral stress fractures. We describe a case of multifocal subchondral stress fractures involving femoral heads and medial tibial condyles bilaterally within 2 weeks. A 27-year-old military recruit began having left knee pain after 2 weeks of basic training, without any injury. Subsequently, right knee, right hip, and left hip pain developed sequentially within 2 weeks. The diagnosis of multifocal subchondral stress fracture was confirmed by plain radiographs and MR images. Nonoperative treatment of the subchondral stress fractures of both medial tibial condyles and the left uncollapsed femoral head resulted in resolution of symptoms. The collapsed right femoral head was treated with a fibular strut allograft to restore congruity and healed without further collapse. There has been one case report in which an insufficiency-type subchondral stress fracture of the femoral head and medial femoral condyle occurred within a 2-year interval. Because the incidence of bilateral subchondral stress fractures of the femoral head is low and multifocal involvement has not been reported, multifocal subchondral stress fractures can be confused with multifocal osteonecrosis. Our case shows that subchondral stress fractures can occur in multiple sites almost simultaneously.

  5. Can Double Osteotomy Be a Solution for Adult Hallux Valgus Deformity With an Increased Distal Metatarsal Articular Angle?

    Science.gov (United States)

    Park, Chul Hyun; Cho, Jae Ho; Moon, Jeong Jae; Lee, Woo Chun

    2016-01-01

    No previous study has reported the results of double metatarsal osteotomy for adult hallux valgus deformity with an increased distal metatarsal articular angle (DMAA). The purpose of the present study was to evaluate the results after double metatarsal osteotomy in adult patients with incongruent hallux valgus deformity. We retrospectively reviewed 16 cases of consecutive first metatarsal double metatarsal osteotomy without lateral soft tissue release in 14 patients with symptomatic hallux valgus associated with an increased DMAA (≥15° after proximal chevron osteotomy on intraoperative radiographs). Clinical results were assessed using the American Orthopaedic Foot and Ankle Society scale and the visual analog scale. The radiographic results were assessed over time, and changes in the DMAA and the relative length of the first metatarsal were assessed by measuring each value preoperatively and at the last follow-up visit. The American Orthopaedic Foot and Ankle Society and visual analog scale scores were significantly improved after surgery. The hallux valgus angle and intermetatarsal angle were stabilized >3 months after surgery. The sesamoid position did not increase significantly beyond the immediate postoperative period. The mean DMAA was corrected from 21.6° (range 15° to 29°) preoperatively to 11.1° (range -2° to 17°) at the last follow-up visit. The mean amount of shortening of the first metatarsal after surgery was 5.5 (range 4 to 7) mm. In conclusion, double metatarsal osteotomy without lateral soft tissue release in adult hallux valgus deformity results in high postoperative recurrence and complication rates. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  6. Stress fracture as a complication of autogenous bone graft harvest from the distal tibia.

    Science.gov (United States)

    Chou, Loretta B; Mann, Roger A; Coughlin, Michael J; McPeake, William T; Mizel, Mark S

    2007-02-01

    Autogenous bone graft from the distal tibia provides cancellous bone graft for foot and ankle operations, and it has osteogenic and osteoconductive properties. The site is in close proximity to the foot and ankle, and published retrospective studies show low morbidity from the procedure. One-hundred autografts were obtained from the distal tibia between 2000 and 2003. In four cases the distal tibial bone graft harvest resulted in a stress fracture. There were three women and one man. The average time of diagnosis of the stress fracture from the operation was 1.8 months. All stress fractures healed with a short course (average 2.4 months) of cast immobilization. This study demonstrated that a stress fracture from the donor site of autogenous bone graft of the distal tibia occurs and can be successfully treated nonoperatively.

  7. Scintigraphic diagnosis of stress-induced incomplete fractures of the proximal tibia

    International Nuclear Information System (INIS)

    Collier, B.D.; Johnson, R.P.; Carrera, G.F.; Akhtar, K.; Isitman, A.T.

    1984-01-01

    Incomplete stress fractures of the proximal tibial diaphysis can be diagnosed by bone scintigraphy. The scintigraphic appearance of incomplete rather than complete tibial stress fractures is apparently reported for the first time in this article. With no treatment other than restricted activity, this injury heals rapidly and completely in 4 to 6 weeks. The major threat to the patient's welfare is unfounded suspicion of tumor or infection which may lead to biopsy or inappropriate therapy

  8. Treatment of medial condylar fractures of the third metatarsus in three horses with fibreglass casts under standing neuroleptanalgesia.

    Science.gov (United States)

    Lloyd, D; Johanson, C; Phillips, T J

    2008-05-03

    Minimally displaced condylar fractures propagating into the third metatarsal diaphysis were treated conservatively in one thoroughbred and two Arabian racehorses. In each case a neuroleptanalgesic protocol provided adequate pain relief for a rigid fibreglass cast to be applied in a weight-bearing position. The fractures healed completely and the three horses recovered uneventfully. Two of them returned successfully to racing and the third was used for breeding.

  9. Unilateral Pedicle Stress Fracture in a Long-Term Hemodialysis Patient with Isthmic Spondylolisthesis

    Directory of Open Access Journals (Sweden)

    Keishi Maruo

    2015-01-01

    Full Text Available Most unilateral pedicle stress fractures occur on the contralateral side of patients with unilateral spondylolysis. However, there are few reports of unilateral pedicle stress fractures in patients with bilateral spondylolysis and spondylolisthesis. We report a unique case of unilateral pedicle stress fracture in a long-term hemodialysis patient with isthmic spondylolisthesis. A 65-year-old man who had undergone hemodialysis presented with lower back pain that had persisted for several years. The patient experienced severe right lower extremity pain with no history of trauma. Computed tomography revealed unilateral pedicle fracture with bilateral L5 spondylolysis and spondylolisthesis with progression of scoliosis. The patient underwent Gill laminectomy of L5 with pedicle screw fixation at L4-S1 and interbody fusion at L5-S1. The patient’s leg pain ceased immediately, and he began walking without leg pain. In our present patient, development of scoliosis caused by destructive spondyloarthropathy may have contributed to a unilateral pedicle fracture.

  10. Fracture toughness and stress relief response of irradiated Type 347/348 stainless steel

    International Nuclear Information System (INIS)

    Haggag, F.M.

    1985-01-01

    A test program has experimentally determined: (1) The fracture toughness of Type 347/348 stainless steel (SS) specimens with high values of irradiation fluence (2.3 to 4.8 x 10 22 n/cm 2 , E > 1.0 MeV) and experiencing different levels of irradiation creep (0.0, 0.6, 1.1, 1.8%), (2) the effect of thermal stress relief on fracture toughness recovery for the highly irradiated material, and (3) the mechanisms associated with fracture toughness recovery due to thermal stress relief. The postirradiation fracture toughness tests and tensile tests were conducted at 427 0 C

  11. Manubrial stress fractures diagnosed on MRI: report of two cases and review of the literature.

    Science.gov (United States)

    Baker, Jonathan C; Demertzis, Jennifer L

    2016-06-01

    In contrast to widely-reported sternal insufficiency fractures, stress fractures of the sternum from overuse are extremely rare. Of the 5 cases of sternal stress fracture published in the English-language medical literature, 3 were in the sternal body and only 2 were in the manubrium. We describe two cases of manubrial stress fracture related to golf and weightlifting, and present the first report of the MR findings of this injury. In each of these cases, the onset of pain was atraumatic, insidious, and associated with increased frequency of athletic activity. Imaging was obtained because of clinical diagnostic uncertainty. On MRI, each patient had a sagittally oriented stress fracture of the lateral manubrium adjacent to the first rib synchondrosis. Both patients had resolution of pain after a period of rest, with subsequent successful return to their respective activities. One patient had a follow-up MRI, which showed resolution of the manubrial marrow edema and fracture line. Based on the sternal anatomy and MR findings, we hypothesize that this rare injury might be caused by repetitive torque of the muscle forces on the first costal cartilage and manubrium, and propose that MRI might be an effective means of diagnosing manubrial stress fracture.

  12. Manubrial stress fractures diagnosed on MRI: report of two cases and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Jonathan C.; Demertzis, Jennifer L. [Washington University School of Medicine, Mallinckrodt Institute of Radiology, Musculoskeletal Section, St Louis, MO (United States)

    2016-06-15

    In contrast to widely-reported sternal insufficiency fractures, stress fractures of the sternum from overuse are extremely rare. Of the 5 cases of sternal stress fracture published in the English-language medical literature, 3 were in the sternal body and only 2 were in the manubrium. We describe two cases of manubrial stress fracture related to golf and weightlifting, and present the first report of the MR findings of this injury. In each of these cases, the onset of pain was atraumatic, insidious, and associated with increased frequency of athletic activity. Imaging was obtained because of clinical diagnostic uncertainty. On MRI, each patient had a sagittally oriented stress fracture of the lateral manubrium adjacent to the first rib synchondrosis. Both patients had resolution of pain after a period of rest, with subsequent successful return to their respective activities. One patient had a follow-up MRI, which showed resolution of the manubrial marrow edema and fracture line. Based on the sternal anatomy and MR findings, we hypothesize that this rare injury might be caused by repetitive torque of the muscle forces on the first costal cartilage and manubrium, and propose that MRI might be an effective means of diagnosing manubrial stress fracture. (orig.)

  13. Manubrial stress fractures diagnosed on MRI: report of two cases and review of the literature

    International Nuclear Information System (INIS)

    Baker, Jonathan C.; Demertzis, Jennifer L.

    2016-01-01

    In contrast to widely-reported sternal insufficiency fractures, stress fractures of the sternum from overuse are extremely rare. Of the 5 cases of sternal stress fracture published in the English-language medical literature, 3 were in the sternal body and only 2 were in the manubrium. We describe two cases of manubrial stress fracture related to golf and weightlifting, and present the first report of the MR findings of this injury. In each of these cases, the onset of pain was atraumatic, insidious, and associated with increased frequency of athletic activity. Imaging was obtained because of clinical diagnostic uncertainty. On MRI, each patient had a sagittally oriented stress fracture of the lateral manubrium adjacent to the first rib synchondrosis. Both patients had resolution of pain after a period of rest, with subsequent successful return to their respective activities. One patient had a follow-up MRI, which showed resolution of the manubrial marrow edema and fracture line. Based on the sternal anatomy and MR findings, we hypothesize that this rare injury might be caused by repetitive torque of the muscle forces on the first costal cartilage and manubrium, and propose that MRI might be an effective means of diagnosing manubrial stress fracture. (orig.)

  14. The impact of in-situ stress and outcrop-based fracture geometry on hydraulic aperture and upscaled permeability in fractured reservoirs

    DEFF Research Database (Denmark)

    Bisdom, Kevin; Bertotti, Giovanni; Nick, Hamid

    2016-01-01

    explicitly, we quantify equivalent permeability, i.e. combined matrix and stress-dependent fracture flow. Fracture networks extracted from a large outcropping pavement form the basis of these models. The results show that the angle between fracture strike and σ 1 has a controlling impact on aperture...

  15. Diagnostic dilemmas in foot and ankle injuries

    Energy Technology Data Exchange (ETDEWEB)

    Keene, J.S.; Lange, R.H.

    1986-07-11

    Differential diagnosis of foot and ankle injuries should include (1) stress fractures of the great toe sesamoids, the shaft of the fifth metatarsal, and the tarsal navicular bone; (2) transchondral talar-dome fractures; (3) fractures of the os trigonum; and (4) dislocating peroneal tendons. Diagnosis of these injuries is challenging because the initial roentgenograms often are normal, and special clinical tests and ancillary studies are required.

  16. Diagnostic dilemmas in foot and ankle injuries

    International Nuclear Information System (INIS)

    Keene, J.S.; Lange, R.H.

    1986-01-01

    Differential diagnosis of foot and ankle injuries should include (1) stress fractures of the great toe sesamoids, the shaft of the fifth metatarsal, and the tarsal navicular bone; (2) transchondral talar-dome fractures; (3) fractures of the os trigonum; and (4) dislocating peroneal tendons. Diagnosis of these injuries is challenging because the initial roentgenograms often are normal, and special clinical tests and ancillary studies are required

  17. Stress fractures of the proximal tibia in runners

    International Nuclear Information System (INIS)

    Daffner, R.H.; Martinez, S.; Gehweiler, J.A.; Harrelson, J.M.

    1982-01-01

    Stress fractures developed along the popliteal-solean line of the posteromedial surface of the tibia in 4 patients as the result of running. Radionuclide bone scans may be useful in early diagnosis of such injuries

  18. Prediction of tectonic stresses and fracture networks with geomechanical reservoir models

    International Nuclear Information System (INIS)

    Henk, A.; Fischer, K.

    2014-09-01

    This project evaluates the potential of geomechanical Finite Element (FE) models for the prediction of in situ stresses and fracture networks in faulted reservoirs. Modeling focuses on spatial variations of the in situ stress distribution resulting from faults and contrasts in mechanical rock properties. In a first methodological part, a workflow is developed for building such geomechanical reservoir models and calibrating them to field data. In the second part, this workflow was applied successfully to an intensively faulted gas reservoir in the North German Basin. A truly field-scale geomechanical model covering more than 400km 2 was built and calibrated. It includes a mechanical stratigraphy as well as a network of 86 faults. The latter are implemented as distinct planes of weakness and allow the fault-specific evaluation of shear and normal stresses. A so-called static model describes the recent state of the reservoir and, thus, after calibration its results reveal the present-day in situ stress distribution. Further geodynamic modeling work considers the major stages in the tectonic history of the reservoir and provides insights in the paleo stress distribution. These results are compared to fracture data and hydraulic fault behavior observed today. The outcome of this project confirms the potential of geomechanical FE models for robust stress and fracture predictions. The workflow is generally applicable and can be used for modeling of any stress-sensitive reservoir.

  19. Prediction of tectonic stresses and fracture networks with geomechanical reservoir models

    Energy Technology Data Exchange (ETDEWEB)

    Henk, A.; Fischer, K. [TU Darmstadt (Germany). Inst. fuer Angewandte Geowissenschaften

    2014-09-15

    This project evaluates the potential of geomechanical Finite Element (FE) models for the prediction of in situ stresses and fracture networks in faulted reservoirs. Modeling focuses on spatial variations of the in situ stress distribution resulting from faults and contrasts in mechanical rock properties. In a first methodological part, a workflow is developed for building such geomechanical reservoir models and calibrating them to field data. In the second part, this workflow was applied successfully to an intensively faulted gas reservoir in the North German Basin. A truly field-scale geomechanical model covering more than 400km{sup 2} was built and calibrated. It includes a mechanical stratigraphy as well as a network of 86 faults. The latter are implemented as distinct planes of weakness and allow the fault-specific evaluation of shear and normal stresses. A so-called static model describes the recent state of the reservoir and, thus, after calibration its results reveal the present-day in situ stress distribution. Further geodynamic modeling work considers the major stages in the tectonic history of the reservoir and provides insights in the paleo stress distribution. These results are compared to fracture data and hydraulic fault behavior observed today. The outcome of this project confirms the potential of geomechanical FE models for robust stress and fracture predictions. The workflow is generally applicable and can be used for modeling of any stress-sensitive reservoir.

  20. Understanding the etiology of the posteromedial tibial stress fracture.

    Science.gov (United States)

    Milgrom, Charles; Burr, David B; Finestone, Aharon S; Voloshin, Arkady

    2015-09-01

    Previous human in vivo tibial strain measurements from surface strain gauges during vigorous activities were found to be below the threshold value of repetitive cyclical loading at 2500 microstrain in tension necessary to reduce the fatigue life of bone, based on ex vivo studies. Therefore it has been hypothesized that an intermediate bone remodeling response might play a role in the development of tibial stress fractures. In young adults tibial stress fractures are usually oblique, suggesting that they are the result of failure under shear strain. Strains were measured using surface mounted unstacked 45° rosette strain gauges on the posterior aspect of the flat medial cortex just below the tibial midshaft, in a 48year old male subject while performing vertical jumps, staircase jumps and running up and down stadium stairs. Shear strains approaching 5000 microstrain were recorded during stair jumping and vertical standing jumps. Shear strains above 1250 microstrain were recorded during runs up and down stadium steps. Based on predictions from ex vivo studies, stair and vertical jumping tibial shear strain in the test subject was high enough to potentially produce tibial stress fracture subsequent to repetitive cyclic loading without necessarily requiring an intermediate remodeling response to microdamage. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Heat induced fracturing of rock in an existing uniaxial stress field

    International Nuclear Information System (INIS)

    Mathis, J.; Stephansson, O.; Bjarnason, B.; Hakami, H.; Herdocia, A.; Mattila, U.; Singh, U.

    1986-01-01

    This study was initiated under the premise that it may be possible to determine the state of stress in the earth's crust by heat induced fracturing of the rock surrounding a borehole. The theory involved is superficially simple, involving the superposition of the stress field around a borehole due to the existing virgin stresses and the uniform stress field of thermally loaded rock as induced by a heater. Since the heat stress field is uniform, varying only in magnitude and gradient as a function of heater input, fracturing should be controlled by the non-uniform virgin stress field. To determine if the method was, in fact, feasible, a series of laboratory test were conducted. These tests consisted of physically loading center drilled cubes of rock, 0.3 m on a side, uniaxially from 0 to 25 MPa. The blocks were then thermally loaded with a nominally rated 3.7 kW heater until failure occurred. Results from these laboratory tests were then compared to analytical studies of the problem, i.e., finite element and discrete theoretical analysis. Overall, results were such that the method is likely eliminated as a stress measurement technique. The immediate development of a thermal compressive zone on the borehole wall overlaps the tensile zone created by the uniaxial stress field, forcing the failure is thus controlled largely by the power input of the heater, being retarded by the small compressive stresses genrated by the uniaxial stress field. This small retardation effect is of such low magnitude that the retardation effect is of such low magnitude that the fracture time is relatively insensitive to the local virgin stress field. (authors)

  2. Dynamic Stress Testing Is Unnecessary for Unimalleolar Supination-External Rotation Ankle Fractures with Minimal Fracture Displacement on Lateral Radiographs.

    Science.gov (United States)

    Nortunen, Simo; Leskelä, Hannu-Ville; Haapasalo, Heidi; Flinkkilä, Tapio; Ohtonen, Pasi; Pakarinen, Harri

    2017-03-15

    This study aimed to identify factors from standard radiographs that contributed to the stability of the ankle mortise in patients with isolated supination-external rotation fractures of the lateral malleolus (OTA/AO 44-B). Non-stress radiographs of the mortise and lateral views, without medial clear space widening or incongruity, were prospectively collected for 286 consecutive patients (mean age, 45 years [range, 16 to 85 years]), including 144 female patients (mean age, 50 years [range, 17 to 85 years]) and 142 male patients (mean age, 40 years [range, 16 to 84 years]) from 2 trauma centers. The radiographs were analyzed for fracture morphology by 2 orthopaedic surgeons, who were blinded to each other's measurements and to the results of external rotation stress radiographs (the reference for stability). Factors significantly associated with ankle mortise stability were tested in multiple logistic regression. Receiver operating characteristic analyses were performed for continuous variables to determine optimal thresholds. A sensitivity of >90% was used as the criterion for an optimal threshold. According to external rotation stress radiographs, 217 patients (75.9%) had a stable injury, defined as that with a medial clear space of ankle mortise were female sex (odds ratio [OR], 2.5 [95% confidence interval (CI), 1.4 to 4.6]), a posterior diastasis of fracture fragments (OR, 7.3 [95% CI, 2.1 to 26.3]). When the posterior diastasis was fracture fragments were present, the probability of a stable ankle mortise was 0.98 for 48 female patients (16.8%) and 0.94 for 37 male patients (12.9%). Patients with noncomminuted lateral malleolar fractures (85 patients [29.7%]) could be diagnosed with a stable ankle mortise without further stress testing, when the fracture line widths were <2 mm on lateral radiographs. Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  3. Unusual stress fracture in an adolescent baseball pitcher affecting the trochlear groove of the olecranon

    International Nuclear Information System (INIS)

    Blake, Joseph J.; Block, John J.; Kan, J.H.; Hannah, Gene A.

    2008-01-01

    Stress fractures of the proximal ulna are known to occur in throwing athletes. Most cases extend to involve the olecranon, and cases limited to the trochlear groove are rare. In this report we present a 17-year-old elite baseball pitcher with a stress fracture of the trochlear groove of the proximal ulna. Diagnosis was made by demonstration of characteristic signal changes on MRI of the elbow. The fracture occurred at the cortical notch, also known as the pseudodefect of the trochlear groove. This case suggests that the cortical notch serves as an area of weakness predisposing pitchers to development of a stress fracture. (orig.)

  4. Fatigue Stress Fracture of the Talar Body: An Uncommon Cause of Ankle Pain.

    Science.gov (United States)

    Kim, Young Sung; Lee, Ho Min; Kim, Jong Pil; Moon, Han Sol

    2016-01-01

    Fatigue stress fractures of the talus are rare and usually involve the head of the talus in military recruits. We report an uncommon cause of ankle pain due to a fatigue stress fracture of the body of the talus in a 32-year-old male social soccer player. Healing was achieved after weightbearing suppression for 6 weeks. Although rare, a stress fracture of the body of the talus should be considered in an athlete with a gradual onset of chronic ankle pain. Magnetic resonance imaging and bone scan are useful tools for early diagnosis. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Stress fractures of the ribs in elite competitive rowers: a report of nine cases

    Energy Technology Data Exchange (ETDEWEB)

    Dragoni, S. [Institute of Sport Medicine and Science of the Italian Olympic Committee, Department of Radiology, Rome (Italy); Giombini, A.; Ripani, M. [University of Motor Sciences, Department of Health, Rome (Italy); Di Cesare, A. [University of Rome ' ' La Sapienza' ' , Department of Physical Medicine and Rehabilitation, Rome (Italy); Magliani, G. [Medical Department of the Italian State Police, Rome (Italy)

    2007-10-15

    The objective was to report the clinical and imaging patterns of nine cases of stress fractures of the rib diagnosed in Italian Olympic rowers. Nine patients with stress fractures of the rib detected from 103 (8.7%) Italian team rowers competing between May 2000 and May 2006 were identified based on the database of a sports medicine institute. All athletes were male. They were aged between 17 and 31 years (mean: 24.4). Patient weight, fracture location, rowing side and imaging methods employed were noted. The diagnosis was made based on history, clinical examination and Tc-99m MDP bone scintigraphy. Eight of the 9 fractures were located anterolaterally between the fourth and ninth rib. In 1 of the 5 athletes with standard radiographs, a fracture line was visible and in 4 there was callus formation. In 2 athletes sonography was performed, which detected discontinuity of the rib surface and callus formation (1 case each). Stress fractures of the ribs are relatively common in competitive rowers. They are characterized by increasing lateral chest pain and typical scintigraphic, radiographic and sonographic findings. (orig.)

  6. Stress fractures of the ribs in elite competitive rowers: a report of nine cases

    International Nuclear Information System (INIS)

    Dragoni, S.; Giombini, A.; Ripani, M.; Di Cesare, A.; Magliani, G.

    2007-01-01

    The objective was to report the clinical and imaging patterns of nine cases of stress fractures of the rib diagnosed in Italian Olympic rowers. Nine patients with stress fractures of the rib detected from 103 (8.7%) Italian team rowers competing between May 2000 and May 2006 were identified based on the database of a sports medicine institute. All athletes were male. They were aged between 17 and 31 years (mean: 24.4). Patient weight, fracture location, rowing side and imaging methods employed were noted. The diagnosis was made based on history, clinical examination and Tc-99m MDP bone scintigraphy. Eight of the 9 fractures were located anterolaterally between the fourth and ninth rib. In 1 of the 5 athletes with standard radiographs, a fracture line was visible and in 4 there was callus formation. In 2 athletes sonography was performed, which detected discontinuity of the rib surface and callus formation (1 case each). Stress fractures of the ribs are relatively common in competitive rowers. They are characterized by increasing lateral chest pain and typical scintigraphic, radiographic and sonographic findings. (orig.)

  7. Limb fracture during recovery from general anaesthesia : an often tragic complication of equine anaesthesia : clinical communication

    Directory of Open Access Journals (Sweden)

    T.B. Dzikiti

    2008-05-01

    Full Text Available A 10-year-old Thoroughbred mare was presented for lameness of the left hindlimb as a result of an apical fracture of the lateral proximal sesamoid bone. The mare was ultimately euthanased after suffering catastrophic fractures of the 3rd and 4th metatarsal bones of the contra-lateral hindlimb during an uncoordinated attempt to rise during recovery from general anaesthesia after undergoing arthroscopic surgery. The case report focuses mostly on horse anaesthesia-related mortality, anaesthetic procedure in the horse, possible causes of fractures in horses during recovery and ways in which rate of occurrence of these fractures can be minimised.

  8. Crack-jump mechanism of microvein formation and its implications for stress cyclicity during extension fracturing

    Science.gov (United States)

    Caputo, Riccardo; Hancock, Paul L.

    1998-11-01

    It is well accepted and documented that faulting is produced by the cyclic behaviour of a stress field. Some extension fractures, such as veins characterised by the crack-seal mechanism, have also been presumed to result from repeated stress cycles. In the present note, some commonly observed field phenomena and relationships such as hackle marks and vein and joint spacing, are employed to argue that a stress field can also display cyclic behaviour during extensional fracturing. Indeed, the requirement of critical stress conditions for the occurrence of extensional failure events does not accord with the presence of contemporaneously open nearby parallel fractures. Therefore, because after each fracture event there is stress release within the surrounding volume of rock, high density sets of parallel extensional fractures also strongly support the idea that rocks undergo stress cyclicity during jointing and veining. A comparison with seismological data from earthquakes with dipole mechanical solutions, confirms that this process presently occurs at depth in the Earth crust. Furthermore, in order to explain dense sets of hair-like closely spaced microveins, a crack-jump mechanism is introduced here as an alternative to the crack-seal mechanism. We also propose that as a consequence of medium-scale stress cyclicity during brittle deformation, the re-fracturing of a rock mass occurs in either one or the other of these two possible ways depending on the ratio between the elastic parameters of the sealing material and those of the host rock. The crack-jump mechanism occurs when the former is stronger.

  9. Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study

    OpenAIRE

    Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-ichi

    2017-01-01

    AIM To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). METHODS A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fract...

  10. Navicular stress fractures treated with minimally invasive fixation

    Directory of Open Access Journals (Sweden)

    Korula Mani Jacob

    2013-01-01

    Early intervention with minimally invasive surgery has significantly less morbidity and a reliable early return to active sports and is therefore the best option in high-performance athletes. Materials and Methods: Nine athletes with ten stress fractures of the navicular treated at our institution between April 1991 and October 2000. The mean age of the patients was 22.8 years (range 18-50 years. All patients were treated by minimally invasive screw fixation and early weight bearing mobilization without a cast. The average followup was 7 years (range 2-11 years. Results: Seven of the nine patients returned to their pre-fracture level of sporting activity at an average of 5 months (range 3-9 months. One patient returned to full sporting activity following a delay of 2 years due to an associated tibial stress fracture and one patient had an unsatisfactory result. Long term review at an average of 7 years showed that six of these eight patients who returned to sports remained symptom free with two patients experiencing minimal intermittent discomfort after prolonged activity. Conclusions: We recommend percutaneous screw fixation as a reliable, low morbidity procedure allowing early return to full sporting activity without long term complications or recurrences.

  11. Fracture transmissivity as a function of normal and shear stress: first results in Opalinus Clay

    International Nuclear Information System (INIS)

    Cuss, R.J.; Milodowski, A.; Noy, D.J.; Harrington, J.F.

    2010-01-01

    Document available in extended abstract form only. Rock-mass failure around openings is usually observed in the form of a highly complex fracture network (EDZ), which is heterogeneous in distribution around a circular tunnel opening because of the heterogeneous stress distribution. The orientation of stress with respect to the fracture network is known to be important. The complex heterogeneous stress trajectory and heterogeneous fracture network results in a broad range of stresses and stress directions acting on the open fracture network. During the open stage of a repository, stress will slowly alter as shear movements occur along the fractures, as well as other time-dependent phenomena. As the repository is back filled, the stress field is further altered as the backfill settles and changes volume because of re-saturation. Therefore, a complex and wide ranging stress regime and stress history will result. In a purely mechanical sense, fracture transmissivity is a function of normal stress, shear stress, and fracture aperture. The Selfrac test from Mont Terri showed the change in transmissivity with effective normal stress. This work showed that fracture transmissivity decreased with increasing normal load and that an effective normal stress of 2.5 MPa is sufficient to yield a transmissivity similar to that seen in intact Opalinus clay (OPA). Therefore fracture closure because of normal stresses has been proven to be a quite efficient mechanism in OPA. A new shear rig was designed to investigate the detail of fracture transmissivity in OPA. The experimental configuration uses two prepared blocks that are 60 x 60 mm in size and approximately 20 mm thick. The first test sample had machine ground surfaces in contact with each other, with pore fluid being delivered through the centre of the top block directly to the fracture surface. The experimental programme included two distinct stages. In the first normal load was altered to investigate fracture transmissivity

  12. Tension Band Plating for Chronic Anterior Tibial Stress Fractures in High-Performance Athletes.

    Science.gov (United States)

    Zbeda, Robert M; Sculco, Peter K; Urch, Ekaterina Y; Lazaro, Lionel E; Borens, Olivier; Williams, Riley J; Lorich, Dean G; Wellman, David S; Helfet, David L

    2015-07-01

    Anterior tibial stress fractures are associated with high rates of delayed union and nonunion, which can be particularly devastating to a professional athlete who requires rapid return to competition. Current surgical treatment strategies include intramedullary nailing, which has satisfactory rates of fracture union but an associated risk of anterior knee pain. Anterior tension band plating is a biomechanically sound alternative treatment for these fractures. Tension band plating of chronic anterior tibial stress fractures leads to rapid healing and return to physical activity and avoids the anterior knee pain associated with intramedullary nailing. Case series; Level of evidence, 4. Between 2001 and 2013, there were 13 chronic anterior tibial stress fractures in 12 professional or collegiate athletes who underwent tension band plating after failing nonoperative management. Patient charts were retrospectively reviewed for demographics, injury history, and surgical details. Radiographs were used to assess time to osseous union. Follow-up notes and phone interviews were used to determine follow-up time, return to training time, and whether the patient was able to return to competition. Cases included 13 stress fractures in 12 patients (9 females, 3 males). Five patients were track-and-field athletes, 4 patients played basketball, 2 patients played volleyball, and 1 was a ballet dancer. Five patients were Division I collegiate athletes and 7 were professional or Olympic athletes. Average age at time of surgery was 23.6 years (range, 20-32 years). Osseous union occurred on average at 9.6 weeks (range, 5.3-16.9 weeks) after surgery. Patients returned to training on average at 11.1 weeks (range, 5.7-20 weeks). Ninety-two percent (12/13) eventually returned to preinjury competition levels. Thirty-eight percent (5/13) underwent removal of hardware for plate prominence. There was no incidence of infection or nonunion. Anterior tension band plating for chronic tibial stress

  13. Excess Stress Fractures, Musculoskeletal Injuries, and Health Care Utilization Among Unfit and Overweight Female Army Trainees.

    Science.gov (United States)

    Krauss, Margot R; Garvin, Nadia U; Boivin, Michael R; Cowan, David N

    2017-02-01

    Musculoskeletal injuries are prevalent among military trainees and certain occupations. Fitness and body mass index (BMI) have been associated with musculoskeletal conditions, including stress fractures. The incidence of, and excess health care utilization for, stress fracture and non-stress fracture overuse musculoskeletal injuries during the first 6 months of service is higher among unfit female recruits. Those who exceeded body fat limits are at a greater risk of incident stress fractures, injuries, or health care utilization compared with weight-qualified recruits. Cohort study; Level of evidence, 3. All applicants to the United States Army were required to take a preaccession fitness test during the study period (February 2005-September 2006). The test included a 5-minute step test scored as pass or fail. BMI was recorded at application. There were 2 distinct comparisons made in this study: (1) between weight-qualified physically fit and unfit women and (2) between weight-qualified physically fit women and those who exceeded body fat limits. We compared the incidence of, and excess health care utilization for, musculoskeletal injuries, including stress fractures and physical therapy visits, during the first 183 days of military service. Among the weight-qualified women, unfit participants had a higher non-stress fracture injury incidence and related excess health care utilization rate compared with fit women, with rate ratios of 1.32 (95% CI, 1.14-1.53) and 1.18 (95% CI, 1.10-1.27), respectively. Among fit women, compared with the weight-qualified participants, those exceeding body fat limits had higher rate ratios for non-stress fracture injury incidence and related excess health care utilization of 1.27 (95% CI, 1.07-1.50) and 1.20 (95% CI, 1.11-1.31), respectively. Weight-qualified women who were unfit had a higher incidence of stress fractures and related excess health care utilization compared with fit women, with rate ratios of 1.62 (95% CI, 1

  14. New model for surface fracture induced by dynamical stress

    OpenAIRE

    Andersen, J. V.; Lewis, L. J.

    1997-01-01

    We introduce a model where an isotropic, dynamically-imposed stress induces fracture in a thin film. Using molecular dynamics simulations, we study how the integrated fragment distribution function depends on the rate of change and magnitude of the imposed stress, as well as on temperature. A mean-field argument shows that the system becomes unstable for a critical value of the stress. We find a striking invariance of the distribution of fragments for fixed ratio of temperature and rate of ch...

  15. Displacement and stress fields around rock fractures opened by irregular overpressure variations

    Directory of Open Access Journals (Sweden)

    Shigekazu eKusumoto

    2014-05-01

    Full Text Available Many rock fractures are entirely driven open by fluids such as ground water, geothermal water, gas, oil, and magma. These are a subset of extension fractures (mode I cracks; e.g., dikes, mineral veins and joints referred to as hydrofractures. Field measurements show that many hydrofractures have great variations in aperture. However, most analytical solutions for fracture displacement and stress fields assume the loading to be either constant or with a linear variation. While these solutions have been widely used, it is clear that a fracture hosted by heterogeneous and anisotropic rock is normally subject to loading that is neither constant nor with a linear variation. Here we present new general solutions for the displacement and stress fields around hydrofractures, modelled as two-dimensional elastic cracks, opened by irregular overpressure variations given by the Fourier cosine series. Each solution has two terms. The first term gives the displacement and stress fields due to the average overpressure acting inside the crack; it is given by the initial term of the Fourier coefficients expressing the overpressure variation. The second term gives the displacement and stress fields caused by the overpressure variation; it is given by general terms of the Fourier coefficients and solved through numerical integration. Our numerical examples show that the crack aperture variation closely reflects the overpressure variation. Also, that the general displacement and stress fields close to the crack follow the overpressure variation but tend to be more uniform far from the crack. The present solutions can be used to estimate the displacement and stress fields around any fluid-driven crack, that is, any hydrofracture, as well as its aperture, provided the variation in overpressure can be described by Fourier series. The solutions add to our understanding of local stresses, displacements, and fluid transport associated with hydrofractures in the crust.

  16. Short-term effects of teriparatide versus placebo on bone biomarkers, structure, and fracture healing in women with lower-extremity stress fractures: A pilot study.

    Science.gov (United States)

    Almirol, Ellen A; Chi, Lisa Y; Khurana, Bharti; Hurwitz, Shelley; Bluman, Eric M; Chiodo, Christopher; Matzkin, Elizabeth; Baima, Jennifer; LeBoff, Meryl S

    2016-09-01

    In this pilot, placebo-controlled study, we evaluated whether brief administration of teriparatide (TPTD) in premenopausal women with lower-extremity stress fractures would increase markers of bone formation in advance of bone resorption, improve bone structure, and hasten fracture healing according to magnetic resonance imaging (MRI). Premenopausal women with acute lower-extremity stress fractures were randomized to injection of TPTD 20-µg subcutaneous (s.c.) (n = 6) or placebo s.c. (n = 7) for 8 weeks. Biomarkers for bone formation N-terminal propeptide of type I procollagen (P1NP) and osteocalcin (OC) and resorption collagen type-1 cross-linked C-telopeptide (CTX) and collagen type 1 cross-linked N-telopeptide (NTX) were measured at baseline, 4 and 8 weeks. The area between the percent change of P1NP and CTX over study duration is defined as the anabolic window. To assess structural changes, peripheral quantitative computed topography (pQCT) was measured at baseline, 8 and 12 weeks at the unaffected tibia and distal radius. The MRI of the affected bone assessed stress fracture healing at baseline and 8 weeks. After 8 weeks of treatment, bone biomarkers P1NP and OC increased more in the TPTD- versus placebo-treated group (both p ≤ 0.01), resulting in a marked anabolic window (p ≤ 0.05). Results from pQCT demonstrated that TPTD-treated women showed a larger cortical area and thickness compared to placebo at the weight bearing tibial site, while placebo-treated women had a greater total tibia and cortical density. No changes at the radial sites were observed between groups. According to MRI, 83.3% of the TPTD- and 57.1% of the placebo-treated group had improved or healed stress fractures (p = 0.18). In this randomized, pilot study, brief administration of TPTD showed anabolic effects that TPTD may help hasten fracture healing in premenopausal women with lower-extremity stress fractures. Larger prospective studies are warranted to determine

  17. Critical cleavage fracture stress characterization of A508 nuclear pressure vessel steels

    International Nuclear Information System (INIS)

    Wu, Sujun; Jin, Huijin; Sun, Yanbin; Cao, Luowei

    2014-01-01

    The critical cleavage fracture stress of SA508 Gr.4N and SA508 Gr.3 low alloy reactor pressure vessel (RPV) steels was studied through the combination of experiments and finite element method (FEM) analysis. The results showed that the value of the local cleavage fracture stress, σ F , of SA508 Gr.4N steel was significantly higher than that of SA508 Gr.3 steel. Detailed microstructural analysis was carried out using FEGSEM which revealed much smaller grains, finer and more homogenous carbide particles formed in SA508 Gr.4N steel. Compared with the SA508 Gr.3 steel currently used in the nuclear industry, the SA508 Gr.4N steel possesses higher strength and notch toughness as well as improved cleavage fracture behavior, and is considered a better candidate RPV steel for the next generation nuclear reactors. - Highlights: • Critical cleavage fracture stress was calculated through experiments and FEM. • Effects of both grain and carbide particle sizes on σ F were discussed. • The SA508 Gr.4N steel is a better candidate for the next generation nuclear reactors

  18. A constitutive equation for creep fracture under constant, variable or cyclic positive stress

    International Nuclear Information System (INIS)

    Snedden, J.D.

    1977-01-01

    Prediction of creep fracture of metals under variable stress is one of the most difficult problems of applied mechanics. At NEL this problem is under investigation using an approach in which creep is represented by two macroscopic components: an anelastic (reversible) component and a plastic (irreversible) component. Under variable loading conditions, the anelastic component's behaviour will be most important and, if an experimental programme is logically planned, the structural processes responsible will be implicit in the resulting constitutive equation describing the material's behaviour. The present paper deals with the development and application of a constitutive equation for creep fracture of RR58 Aluminium alloy at 180 0 C under variable stress and such a constitutive equation can be extrapolated to cover long-time behaviour just as with conventional constant stress creep fracture equations. Constant stress, in fact, is one of the boundary conditions of the general constitutive equation, representing zero prior damage. The other boundary condition is that of 'cadence loading' in which the stress is completely removed and then re-applied in a cyclic fashion. (Auth.)

  19. CHARACTERIZATION OF IN-SITU STRESS AND PERMEABILITY IN FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Burns; M. Nafi Toksoz

    2002-12-31

    We have extended a three-dimensional finite difference elastic wave propagation model previously developed at the Massachusetts Institute of Technology (MIT) Earth Resources Laboratory (ERL) for modeling and analyzing the effect of fractures on seismic waves. The code has been translated into C language and parallelized [using message passing interface (MPI)] to allow for larger models to be run on Linux PC computer clusters. We have also obtained another 3-D code from Lawrence Berkeley Laboratory, which we will use for verification of our ERL code results and also to run discrete fracture models. Testing of both codes is underway. We are working on a new finite difference model of borehole wave propagation for stressed formations. This code includes coordinate stretching to provide stable, variable grid sizes that will allow us to model the thin fluid annulus layers in borehole problems, especially for acoustic logging while drilling (LWD) applications. We are also extending our analysis routines for the inversion of flexural wave dispersion measurements for in situ stress estimates. Initial results on synthetic and limited field data are promising for a method to invert cross dipole data for the rotation angle and stress state simultaneously. A meeting is being scheduled between MIT and Shell Oil Company scientists to look at data from a fractured carbonate reservoir that may be made available to the project. The Focus/Disco seismic processing system from Paradigm Geophysical has been installed at ERL for field data analysis and as a platform for new analysis modules. We have begun to evaluate the flow properties of discrete fracture distributions through a simple 2D numerical model. Initial results illustrate how fluid flow pathways are very sensitive to variations in the geometry and apertures of fracture network.

  20. Natural Fractures Characterization and In Situ Stresses Inference in a Carbonate Reservoir—An Integrated Approach

    Directory of Open Access Journals (Sweden)

    Ali Shafiei

    2018-02-01

    Full Text Available In this paper, we characterized the natural fracture systems and inferred the state of in situ stress field through an integrated study in a very complex and heterogeneous fractured carbonate reservoir. Relative magnitudes and orientations of the in-situ principal stresses in a naturally fractured carbonate heavy oil field were estimated with a combination of available data (World Stress Map, geological and geotectonic evidence, outcrop studies and techniques (core analysis, borehole image logs and Side View Seismic Location. The estimates made here using various tools and data including routine core analysis and image logs are confirmatory to estimates made by the World Stress Map and geotectonic facts. NE-SW and NW-SE found to be the dominant orientations for maximum and minimum horizontal stresses in the study area. In addition, three dominant orientations were identified for vertical and sub-vertical fractures atop the crestal region of the anticlinal structure. Image logs found useful in recognition and delineation of natural fractures. The results implemented in a real field development and proved practical in optimal well placement, drilling and production practices. Such integrated studies can be instrumental in any E&P projects and related projects such as geological CO2 sequestration site characterization.

  1. Pace bowlers in cricket with history of lumbar stress fracture have increased risk of lower limb muscle strains, particularly calf strains.

    Science.gov (United States)

    Orchard, John; Farhart, Patrick; Kountouris, Alex; James, Trefor; Portus, Marc

    2010-01-01

    To assess whether a history of lumbar stress fracture in pace bowlers in cricket is a risk factor for lower limb muscle strains. This was a prospective cohort risk factor study, conducted using injury data from contracted first class pace bowlers in Australia during seasons 1998-1999 to 2008-2009 inclusive. There were 205 pace bowlers, 33 of whom suffered a lumbar stress fracture when playing first class cricket. Risk ratios ([RR] with 95% confidence intervals[CI]) were calculated to compare the seasonal incidence of various injuries between bowlers with a prior history of lumbar stress fracture and those with no history of lumbar stress fracture. Risk of calf strain was strongly associated with prior lumbar stress fracture injury history (RR = 4.1; 95% CI: 2.4-7.1). Risks of both hamstring strain (RR = 1.5; 95% CI: 1.03-2.1) and quadriceps strain (RR = 2.0; 95% CI: 1.1-3.5) were somewhat associated with history of lumbar stress fracture. Risk of groin strain was not associated with history of lumbar stress fracture (RR = 0.7; 95% CI: 0.4-1.1). Other injuries showed little association with prior lumbar stress fracture, although knee cartilage injuries were more likely in the non-stress fracture group. Bony hypertrophy associated with lumbar stress fracture healing may lead to subsequent lumbar nerve root impingement, making lower limb muscle strains more likely to occur. Confounders may be responsible for some of the findings. In particular, bowling speed is likely to be independently correlated with risk of lumbar stress fracture and risk of muscle strain. However, as the relationship between lumbar stress fracture history and calf strain was very strong, and that there is a strong theoretical basis for the connection, it is likely that this is a true association.

  2. Plantar pressure relief under the metatarsal heads: therapeutic insole design using three-dimensional finite element model of the foot.

    Science.gov (United States)

    Chen, Wen-Ming; Lee, Sung-Jae; Lee, Peter Vee Sin

    2015-02-26

    Therapeutic footwear with specially-made insoles is often used in people with diabetes and rheumatoid arthritis to relieve ulcer risks and pain due to high pressures from areas beneath bony prominences of the foot, in particular to the metatarsal heads (MTHs). In a three-dimensional finite element study of the foot and footwear with sensitivity analysis, effects of geometrical variations of a therapeutic insole, in terms of insole thicknesses and metatarsal pad (MP) placements, on local peak plantar pressure under MTHs and stress/strain states within various forefoot tissues, were determined. A validated musculoskeletal finite element model of the human foot was employed. Analyses were performed in a simulated muscle-demanding instant in gait. For many design combinations, increasing insole thicknesses consistently reduce peak pressures and internal tissue strain under MTHs, but the effects reach a plateau when insole becomes very thick (e.g., a value of 12.7mm or greater). Altering MP placements, however, showed a proximally- and a distally-placed MP could result in reverse effects on MTH pressure-relief. The unsuccessful outcome due to a distally-placed MP may attribute to the way it interacts with plantar tissue (e.g., plantar fascia) adjacent to the MTH. A uniform pattern of tissue compression under metatarsal shaft is necessary for a most favorable pressure-relief under MTHs. The designated functions of an insole design can best be achieved when the insole is very thick, and when the MP can achieve a uniform tissue compression pattern adjacent to the MTH. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Stress localization in BCC polycrystals and its implications on the probability of brittle fracture

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, Ludovic [CEA, DEN, SRMA, 91191 Gif sur Yvette Cedex (France); Gelebart, Lionel, E-mail: lionel.gelebart@cea.fr [CEA, DEN, SRMA, 91191 Gif sur Yvette Cedex (France); Dakhlaoui, Rim; Marini, Bernard [CEA, DEN, SRMA, 91191 Gif sur Yvette Cedex (France)

    2011-07-15

    Highlights: {yields} Intergranular stress distributions in a bainitic steel. {yields} Comparison of local mean stress field with neutron diffraction results. {yields} Application of the local stress distribution in a brittle fracture model. - Abstract: The evaluation of the reliability of pressure vessels in nuclear plants relies on the evaluation of failure probability models. Micromechanical approaches are of great interest to refine their description, to better understand the underlying mechanisms leading to failure, and finally to improve the prediction of these models. The main purpose of this paper is to introduce the stress heterogeneities arising within the polycrystal in a probabilistic modeling of brittle fracture. Stress heterogeneities are evaluated from Finite-Element simulations performed on a large number of Statistical Volume Elements. Results are validated both on the measured averaged behavior and on the averaged stresses measured by neutron diffraction in five specific orientations. A probabilistic model for brittle fracture is then presented accounting for the carbide distribution and the stress distribution evaluated previously inside an elementary volume V{sub 0}. Results are compared to a 'Beremin type' approach, assuming a homogeneous stress state inside V{sub 0}.

  4. Sacral Stress Fracture following the Bone Union of Lumbar Spondylolysis

    Directory of Open Access Journals (Sweden)

    Tatsuro Sasaji

    2016-01-01

    Full Text Available While 22 articles have reported on sacral stress fractures, it is a rare injury and its etiology is not well known. We present the case of a 16-year-old male who presented with low back pain in 2015. He was a high school soccer player with a previous history of a bilateral L5 lumbar spondylolysis in 2014. The patient refrained from soccer and wore a brace for six months. Two months after restarting soccer, he again complained of low back pain. After 1 year, a lumbar spine computed tomography revealed the bone union of the spondylolysis. At his first visit to our hospital, his general and neurological conditions were normal and laboratory data were within the normal range. Sacral coronal magnetic resonance imaging (MRI of the left sacral ala revealed an oblique lineal signal void surrounding bone marrow edema. Based on his symptoms, sports history, and MRI, he was diagnosed with a sacral stress fracture. He again refrained from soccer; his low back pain soon improved, and, after 1 year, the abnormal signal change had disappeared on sacral MRI. Recurrent low back pain case caused by a sacral stress fracture occurring after the bone union of lumbar spondylolysis is uncommon.

  5. Diagnostic accuracy of magnetic resonance imaging versus computed tomography in stress fractures of the lumbar spine

    International Nuclear Information System (INIS)

    Ganiyusufoglu, A.K.; Onat, L.; Karatoprak, O.; Enercan, M.; Hamzaoglu, A.

    2010-01-01

    Aim: To compare the diagnostic accuracy of magnetic resonance imaging (MRI) with computed tomography (CT) in stress fractures of the lumbar spine. Materials and methods: Radiological and clinical data from 57 adolescents and young adults with a diagnosis of stress injury of the lumbar spine were retrospectively reviewed. All cases had undergone both 1.5 T MRI and 16-section CT examinations. All MRI and CT images were retrospectively reviewed and evaluated in separate sessions. The fracture morphology (complete/incomplete, localization) and vertebral levels were noted at both the CT and MRI examinations. Bone marrow/peri-osseous soft-tissue oedema was also determined at MRI. Results: In total, 73 complete and 32 incomplete stress fractures were detected with CT. Sixty-seven complete, 24 incomplete fractures and eight stress reactions were detected using MRI in the same study group. Marrow oedema was also seen in eight of the complete and 20 of the incomplete fractures. The specificity, sensitivity, and accuracy of MRI in detecting fracture lines were 99.6, 86.7, and 97.2%, respectively. MRI was more accurate at the lower lumbar levels in comparison to upper lumbar levels. Conclusion: MRI has a similar diagnostic accuracy to CT in determining complete fractures with or without accompanying marrow oedema and incomplete fractures with accompanying marrow oedema, especially at the lower lumbar levels, which constitutes 94% of all fractures. At upper lumbar levels and in the incomplete fractures of the pars interarticularis with marked surrounding sclerosis, MRI has apparent limitations compared to CT imaging.

  6. Diagnostic accuracy of magnetic resonance imaging versus computed tomography in stress fractures of the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Ganiyusufoglu, A.K., E-mail: kursady33@yahoo.co [Department of Radiology, Florence Nightingale Hospital, Istanbul (Turkey); Onat, L. [Department of Radiology, Florence Nightingale Hospital, Istanbul (Turkey); Karatoprak, O.; Enercan, M.; Hamzaoglu, A. [Department of Orthopedics and Traumatology, Florence Nightingale Hospital, Istanbul (Turkey)

    2010-11-15

    Aim: To compare the diagnostic accuracy of magnetic resonance imaging (MRI) with computed tomography (CT) in stress fractures of the lumbar spine. Materials and methods: Radiological and clinical data from 57 adolescents and young adults with a diagnosis of stress injury of the lumbar spine were retrospectively reviewed. All cases had undergone both 1.5 T MRI and 16-section CT examinations. All MRI and CT images were retrospectively reviewed and evaluated in separate sessions. The fracture morphology (complete/incomplete, localization) and vertebral levels were noted at both the CT and MRI examinations. Bone marrow/peri-osseous soft-tissue oedema was also determined at MRI. Results: In total, 73 complete and 32 incomplete stress fractures were detected with CT. Sixty-seven complete, 24 incomplete fractures and eight stress reactions were detected using MRI in the same study group. Marrow oedema was also seen in eight of the complete and 20 of the incomplete fractures. The specificity, sensitivity, and accuracy of MRI in detecting fracture lines were 99.6, 86.7, and 97.2%, respectively. MRI was more accurate at the lower lumbar levels in comparison to upper lumbar levels. Conclusion: MRI has a similar diagnostic accuracy to CT in determining complete fractures with or without accompanying marrow oedema and incomplete fractures with accompanying marrow oedema, especially at the lower lumbar levels, which constitutes 94% of all fractures. At upper lumbar levels and in the incomplete fractures of the pars interarticularis with marked surrounding sclerosis, MRI has apparent limitations compared to CT imaging.

  7. Alveolar rhabdomyosarcoma originating between the fourth and fifth metatarsal--case report and literature review.

    LENUS (Irish Health Repository)

    Bolger, J C

    2010-09-01

    We report a case of alveolar rhabdomyosarcoma arising between the fourth and fifth metatarsal. A 13-year-old boy presented to outpatients with a history of pain and swelling in the lateral aspect of his left forefoot. Plain radiographs and MRI showed a soft tissue mass displacing the fourth metatarsal. Percutaneous biopsy revealed an alveolar rhabdomyosarcoma. Staging scans showed advanced metastatic disease. The patient was treated with chemotherapy. This highly malignant lesion remains challenging to diagnose, and difficult to treat successfully.

  8. Radiological Outcome of Patients with Splay Foot Following First and Fifth Metatarsal Osteotomies Performed Simultaneously on the Same Foot

    Directory of Open Access Journals (Sweden)

    Hadi Mohammed

    2012-12-01

    Conclusion: The results suggest a very good radiological outcome in symptomatic patients following simultaneous first and fifth metatarsal osteotomies. All the angles measured postoperatively, except the distal metatarsal articular angle, showed a statistically significant reduction.

  9. Bilateral stress fractures of femoral neck in non-athletes: a report of four cases

    Directory of Open Access Journals (Sweden)

    Naik Monappa A

    2013-04-01

    Full Text Available 【Abstract】Femoral neck stress fractures (FNSFs are rare, constituting only 5% of all stress fractures in young adults. These fractures are usually seen in athletes, military recruits and patients with underlying metabolic diseases. The treatment of FNSFs is still controversial because of the inherent complications associated with the treatment procedure. We came across 4 cases of bilateral FNSFs in non-athletic individuals who were manual labourers with-out underlying bony disorders. Two patients with FNSFs and coxa vara deformity on both sides were managed by subtrochanteric valgus osteotomy and dynamic hip screw fixation. One of the remaining two patients was treated by cannulated cancellous screw fixation on one side and sub-trochanteric valgus osteotomy on the other side. The fourth patient received subtrochanteric valgus osteotomy on one side and bipolar hemiarthroplasty on the other side after failed cannulated screw fixation. All the fractures healed without any complications. No evidence of avascular ne-crosis or arthritis was noted in our series. Subtrochanteric valgus osteotomy restores normal neck-shaft angle in pa-tients suffering from FNSFs combined with coxa vara deformity. Moreover, it helps to bring the forces acting around the hip to normal biomechanical levels, leading to fracture union and better results. Replacement arthroplasty is recommended to patients who fail to achieve bony union after fixation. Key words: Fractures, stress; Femoral neck fractures; Coxa vara; Osteotomy

  10. Hypermobility of the first metatarsal bone in patients with Rheumatoid arthritis treated by lapidus procedure

    Directory of Open Access Journals (Sweden)

    Popelka Stanislav

    2012-08-01

    Full Text Available Abstract Background Foot deformities and related problems of the forefoot are very common in patients with rheumatoid arthritis. The laxity of the medial cuneometatarsal joint and its synovitis are important factors in the development of forefoot deformity. The impaired joint causes the first metatarsal bone to become unstable in the frontal and sagittal planes. In this retrospective study we evaluated data of patients with rheumatoid arthritis who underwent Lapidus procedure. We evaluated the role of the instability in a group of patients, focusing mainly on the clinical symptoms and X-ray signs of the instability. Methods The study group included 125 patients with rheumatoid arthritis. The indications of the Lapidus procedure were a hallux valgus deformity greater than 15 degrees and varus deformity of the first metatarsal bone with the intermetatarsal angle greater than 15 degrees on anterio-posterior weight-bearing X-ray. Results Data of 143 Lapidus procedures of 125 patients with rheumatoid arthritis, who underwent surgery between 2004 and 2010 was evaluated. Signs and symptoms of the first metatarsal bone instability was found in 92 feet (64.3% in our group. The AOFAS score was 48.6 before and 87.6 six months after the foot reconstruction. Nonunion of the medial cuneometatarsal joint arthrodesis on X-rays occurred in seven feet (4.9%. Conclusion The Lapidus procedure provides the possibility to correct the first metatarsal bone varus position and its instability, as well as providing the possibility to achieve a painless foot for walking. We recommend using the procedure as a preventive surgery in poorly symptomatic patients with rheumatoid arthritis in case of the first metatarsal bone hypermobility.

  11. Acute changes in foot strike pattern and cadence affect running parameters associated with tibial stress fractures.

    Science.gov (United States)

    Yong, Jennifer R; Silder, Amy; Montgomery, Kate L; Fredericson, Michael; Delp, Scott L

    2018-05-18

    Tibial stress fractures are a common and debilitating injury that occur in distance runners. Runners may be able to decrease tibial stress fracture risk by adopting a running pattern that reduces biomechanical parameters associated with a history of tibial stress fracture. The purpose of this study was to test the hypothesis that converting to a forefoot striking pattern or increasing cadence without focusing on changing foot strike type would reduce injury risk parameters in recreational runners. Running kinematics, ground reaction forces and tibial accelerations were recorded from seventeen healthy, habitual rearfoot striking runners while running in their natural running pattern and after two acute retraining conditions: (1) converting to forefoot striking without focusing on cadence and (2) increasing cadence without focusing on foot strike. We found that converting to forefoot striking decreased two risk factors for tibial stress fracture: average and peak loading rates. Increasing cadence decreased one risk factor: peak hip adduction angle. Our results demonstrate that acute adaptation to forefoot striking reduces different injury risk parameters than acute adaptation to increased cadence and suggest that both modifications may reduce the risk of tibial stress fractures. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Bilateral periprosthetic tibial stress fracture after total knee arthroplasty: A case report.

    Science.gov (United States)

    Ozdemir, Guzelali; Azboy, Ibrahim; Yilmaz, Baris

    2016-01-01

    Periprosthetic fractures around the knee after total knee arthroplasty can be seen in the femur, tibia and patella. The tibial fractures are rare cases. Our case with bilateral tibial stress fracture developed after total knee arthroplasty (TKA) is the first of its kind in the literature. 75-year-old male patient with bilateral knee osteoarthritis had not benefited from conservative treatment methods previously applied. Left TKA was applied. In the second month postoperatively, periprosthetic tibial fracture was identified and osteosynthesis was implemented with locked tibia proximal plate-screw. Bone union in 12 weeks was observed in his follow-ups. After 15 months of his first operation, TKA was applied to the right knee. Postoperatively in the second month, as in the first operation, periprosthetic tibial fracture was detected. Osteosynthesis with locking plate-screw was applied and union in 12 weeks was observed in his follow-up. He was seen mobilized independently and without support in the last control of the case made in the 24th month after the second operation. The number of TKA applications is expected to increase in the future. The incidence of periprosthetic fractures should also be expected to increase in these cases. Periprosthetic tibial fractures after TKA are rarely seen. The treatment of periprosthetic fractures around the knee after TKA can be difficult. In the case of persistent pain in the upper end of the tibia after the surgery, stress fracture should be considered. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Radiographic evaluation of hallux valgus

    International Nuclear Information System (INIS)

    Richardson, M.L.; Hansen, S.T.; Kilcoyne, R.F.

    1987-01-01

    This paper presents the common preoperative and postoperative findings in hallux valgus, a common foot disorder of multiple etiologies, which can lead to significant foot pain and deformity. Little has been published in radiologic literature about the proper initial radiographic workup and the postoperative follow-up of this very common and very treatable cause of foot pain. Besides the primary findings of varus angulation of the first metatarsal and valgus angulation of the great toe, one may also see dorsal slaying of the first metatarsal head. As increased weight is borne by the central metatarsals, they may develop hyperostosis and stress fractures. Angular deformities of the hallux sesamoid joint and lesser toes may also be seen

  14. Stresses, fatigue and fracture analysis in the tube sheets

    International Nuclear Information System (INIS)

    Billon, F.

    1986-05-01

    The purpose of the present work is to study the behaviour of the nuclear PWR steam generator tube sheet. But the methods developed in this field can easily be generalized in order to study tube sheets from any other type of heat exchangers. The aim of the stress analysis of these sheets is to verify their correct design, to quantify the risk of fatigue damage in the areas submitted to a high stress concentration and through the fracture mechanic, to make sure there is no risk of fast fracture resulting from initiated or pre-existing defects. This analysis necessarily relates to the calculation of stresses in all parts of the multidrilled area, mainly around the holes where they are concentrated. However the tube sheets are so complexe structures that their direct modelization cannot be envisaged within the context of the finite element method. We then must refer to the concept of equivalent medium in order to calculate the nominal stresses. Then using the stresses multiple fonctions appropriate to the net geometry, we can calculate the actual stresses concentrated around the holes. The method depends on the behaviour of the elementary volume which represents the behaviour of the multidrilled medium. This approach must allow to correctly take account of the ''thermal skin effect'', which is a phenomenon particular to the tube sheets with thermal loads. It must as well be generalized in order to analyse the irregular ligaments which affect the periodical stresses distribution and locally overconcentrate them [fr

  15. Nutritional factors that influence change in bone density and stress fracture risk among young female cross-country runners.

    Science.gov (United States)

    Nieves, Jeri W; Melsop, Kathryn; Curtis, Meredith; Kelsey, Jennifer L; Bachrach, Laura K; Greendale, Gail; Sowers, Mary Fran; Sainani, Kristin L

    2010-08-01

    To identify nutrients, foods, and dietary patterns associated with stress fracture risk and changes in bone density among young female distance runners. Two-year, prospective cohort study. Observational data were collected in the course of a multicenter randomized trial of the effect of oral contraceptives on bone health. One hundred and twenty-five female competitive distance runners ages 18-26 years. Dietary variables were assessed with a food frequency questionnaire. Bone mineral density and content (BMD/BMC) of the spine, hip, and total body were measured annually by dual x-ray absorptiometry (DEXA). Stress fractures were recorded on monthly calendars, and had to be confirmed by radiograph, bone scan, or magnetic resonance imaging. Seventeen participants had at least one stress fracture during follow-up. Higher intakes of calcium, skim milk, and dairy products were associated with lower rates of stress fracture. Each additional cup of skim milk consumed per day was associated with a 62% reduction in stress fracture incidence (P stress fracture rate. Potassium intake was also associated with greater gains in hip and whole-body BMD. Copyright © 2010 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  16. Marrow changes in anorexia nervosa masking the presence of stress fractures on MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tins, B.; Cassar-Pullicino, V. [Department of Radiology, RJAH Orthopaedic and District Hospital, Oswestry (United Kingdom)

    2006-11-15

    Patients with anorexia nervosa (AN) usually have abnormal bone and bone marrow metabolism resulting in osteopenia and serous bone marrow change. There is an increased risk of stress/insufficiency fractures and these can be the first presentation of AN. This case report describes a patient with previously undiagnosed AN who presented with foot pain. The serous bone marrow changes of AN were found to mask the MR imaging features of stress fractures, as both had low T1w and high T2w and STIR signal intensities. Contrast enhancement was not helpful but actually masked fractures. Scintigraphy was helpful. The radiologist might be the first clinician to raise the possibility of AN and should be aware of the difficulties in diagnosing stress fractures in bones with underlying serous bone marrow change. In this severe case of AN even the heel fat pad and the fat pad in Kager's triangle had undergone serous change.

  17. Marrow changes in anorexia nervosa masking the presence of stress fractures on MR imaging

    International Nuclear Information System (INIS)

    Tins, B.; Cassar-Pullicino, V.

    2006-01-01

    Patients with anorexia nervosa (AN) usually have abnormal bone and bone marrow metabolism resulting in osteopenia and serous bone marrow change. There is an increased risk of stress/insufficiency fractures and these can be the first presentation of AN. This case report describes a patient with previously undiagnosed AN who presented with foot pain. The serous bone marrow changes of AN were found to mask the MR imaging features of stress fractures, as both had low T1w and high T2w and STIR signal intensities. Contrast enhancement was not helpful but actually masked fractures. Scintigraphy was helpful. The radiologist might be the first clinician to raise the possibility of AN and should be aware of the difficulties in diagnosing stress fractures in bones with underlying serous bone marrow change. In this severe case of AN even the heel fat pad and the fat pad in Kager's triangle had undergone serous change

  18. Residual stress effects in LMFBR fracture assessment procedures

    International Nuclear Information System (INIS)

    Hooton, D.G.

    1984-01-01

    Two post-yield fracture mechanics methods, which have been developed into fully detailed failure assessment procedures for ferritic structures, have been reviewed from the point of view of the manner in which as-welded residual stress effects are incorporated, and comparisons then made with finite element and theoretical models of centre-cracked plates containing residual/thermal stresses in the form of crack-driving force curves. Applying the procedures to austenitic structures, comparisons are made in terms of failure assessment curves and it is recommended that the preferred method for the prediction of critical crack sizes in LMFBR austenitic structures containing as-welded residual stresses is the CEGB-R6 procedure based on a flow stress defined at 3% strain in the parent plate. When the prediction of failure loads in such structures is required, it is suggested that the CEGB-R6 procedure be used with residual/thermal stresses factored to give a maximum total stress of flow stress magnitude

  19. Stress, Flow and Particle Transport in Rock Fractures

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Tomofumi

    2007-09-15

    The fluid flow and tracer transport in a single rock fracture during shear processes has been an important issue in rock mechanics and is investigated in this thesis using Finite Element Method (FEM) and streamline particle tracking method, considering evolutions of aperture and transmissivity with shear displacement histories under different normal stresses, based on laboratory tests. The distributions of fracture aperture and its evolution during shear were calculated from the initial aperture fields, based on the laser-scanned surface roughness features of replicas of rock fracture specimens, and shear dilations measured during the coupled shear-flow-tracer tests in laboratory performed using a newly developed testing apparatus in Nagasaki University, Nagasaki, Japan. Three rock fractures of granite with different roughness characteristics were used as parent samples from which nine plaster replicas were made and coupled shear-flow tests was performed under three normal loading conditions (two levels of constant normal loading (CNL) and one constant normal stiffness (CNS) conditions). In order to visualize the tracer transport, transparent acrylic upper parts and plaster lower parts of the fracture specimens were manufactured from an artificially created tensile fracture of sandstone and the coupled shear-flow tests with fluid visualization was performed using a dye tracer injected from upstream and a CCD camera to record the dye movement. A special algorithm for treating the contact areas as zero-aperture elements was used to produce more accurate flow field simulations by using FEM, which is important for continued simulations of particle transport, but was often not properly treated in literature. The simulation results agreed well with the flow rate data obtained from the laboratory tests, showing that complex histories of fracture aperture and tortuous flow channels with changing normal stresses and increasing shear displacements, which were also captured

  20. Pace bowlers in cricket with history of lumbar stress fracture have increased risk of lower limb muscle strains, particularly calf strains

    Directory of Open Access Journals (Sweden)

    John Orchard

    2010-09-01

    Full Text Available John Orchard1, Patrick Farhart2, Alex Kountouris3, Trefor James3, Marc Portus31School of Public Health, University of Sydney, Australia; 2Punjab Kings XI team, Indian Premier League, India; 3Cricket Australia, Melbourne, AustraliaObjective: To assess whether a history of lumbar stress fracture in pace bowlers in cricket is a risk factor for lower limb muscle strains.Methods: This was a prospective cohort risk factor study, conducted using injury data from contracted first class pace bowlers in Australia during seasons 1998–1999 to 2008–2009 inclusive. There were 205 pace bowlers, 33 of whom suffered a lumbar stress fracture when playing first class cricket. Risk ratios ([RR] with 95% confidence intervals[CI] were calculated to compare the seasonal incidence of various injuries between bowlers with a prior history of lumbar stress fracture and those with no history of lumbar stress fracture.Results: Risk of calf strain was strongly associated with prior lumbar stress fracture injury history (RR = 4.1; 95% CI: 2.4–7.1. Risks of both hamstring strain (RR = 1.5; 95% CI: 1.03–2.1 and quadriceps strain (RR = 2.0; 95% CI: 1.1–3.5 were somewhat associated with history of lumbar stress fracture. Risk of groin strain was not associated with history of lumbar stress fracture (RR = 0.7; 95% CI: 0.4–1.1. Other injuries showed little association with prior lumbar stress fracture, although knee cartilage injuries were more likely in the non-stress fracture group.Conclusion: Bony hypertrophy associated with lumbar stress fracture healing may lead to subsequent lumbar nerve root impingement, making lower limb muscle strains more likely to occur. Confounders may be responsible for some of the findings. In particular, bowling speed is likely to be independently correlated with risk of lumbar stress fracture and risk of muscle strain. However, as the relationship between lumbar stress fracture history and calf strain was very strong, and that there is a

  1. Femoral Neck Stress Fractures in Children Younger Than 10 Years of Age.

    Science.gov (United States)

    Boyle, Matthew J; Hogue, Grant D; Heyworth, Benton E; Ackerman, Kathryn; Quinn, Bridget; Yen, Yi-Meng

    2017-03-01

    Femoral neck stress fractures are rare in healthy children, with only 9 cases previously reported. The present article reviews our institutional experience with femoral neck stress fractures in children younger than 10 years of age, to highlight the unique features of this condition. We undertook a retrospective review of clinical records of patients who had been treated at our institution for an idiopathic femoral neck stress fracture between 2000 and 2014. To focus on children rather than adolescents, the World Health Organization's definition of adolescent as a person between 10 and 19 years of age was used; we thereby limited our analysis to patients younger than 10 years of age. The study included 6 patients (3 males, 3 females) treated for an idiopathic femoral neck stress fracture, with a mean age at diagnosis of 7.7 years (range, 5.2 to 8.9 y). All patients presented with a limp, which worsened with activity and had persisted for a mean of 5 weeks (range, 2 to 9 wk). None of the patients had experienced an increase in activity level or sporting volume before symptom onset. On examination, 3 patients experienced pain with terminal hip flexion and 3 patients demonstrated pain-free hip range of motion. Plain radiography demonstrated inferior femoral neck cortical disruption, suggesting a compression-type stress fracture mechanism. The diagnosis was confirmed by cross-sectional imaging in all cases. All patients were initially treated with 6 to 8 weeks of non-weight-bearing followed by 4 to 6 weeks of partial weight-bearing, leading to complete healing in 4 patients. Two patients demonstrated incomplete healing and were managed with spica casting for an additional 6 weeks. Our case series illustrates the unique features of this rare condition in children, with a history and examination profile distinct from those of adolescents and adults. Compliance with weight-bearing restrictions is difficult in this population and hip spica casting may be required to permit

  2. Stress fracture of hamate's hook: case report with emphasis to the imaging findings

    International Nuclear Information System (INIS)

    Carvalho, Leonardo Fontenelle de; Vianna, Evandro Miguelote; Domingues, Romulo; Domingues, Romeu Cortes; Metsavaht, Leonardo

    2007-01-01

    Stress fractures of the hook of the hamate are related to sports that use devices such as golf clubs, rackets and baseball bats. Because usually there is no history of obvious trauma, the diagnosis necessitates better knowledge of the lesion and high index of suspicion. The authors report a case of stress fracture of the hook of the hamate in a golf player with diagnosis and follow-up done with magnetic resonance and multislice computer tomography. (author)

  3. Minimally invasive distal first metatarsal osteotomy can be an option for recurrent hallux valgus.

    Science.gov (United States)

    Magnan, Bruno; Negri, Stefano; Maluta, Tommaso; Dall'Oca, Carlo; Samaila, Elena

    2018-01-12

    Recurrence rate of surgical treatment of hallux valgus ranges in the literature from 2.7% to 16%, regardless of used procedure. In this study, long-term results of a minimally invasive distal osteotomy of the first metatarsal bone for treatment of recurrent hallux valgus are described. 32 consecutive percutaneous distal osteotomies of the first metatarsal were performed in 26 patients for treatment of recurrent hallux valgus. Primary surgery had been soft tissue procedures in 8 cases (25%), first metatarsal or phalangeal osteotomies in 19 cases (59.4%) and Keller procedures in 5 cases (15.6%). Patients were assessed with a mean follow-up of 9.8±4.3 years. All patients reported the disappearance or reduction of the pain. The mean overall AOFAS score improved from 46.9±17.8 points to 85.2±14.9 at final follow-up. The mean hallux valgus angle decreased from 26.1±9.1 to 9.7±5.4°, the intermetatarsal angle decreased from 11.5±4.5 to 6.7±4.0°. No major complications were recorded with a re-recurrence rate of 3.1% (1 case). Percutaneous distal osteotomy of the first metatarsal can be a reliable and safe surgical option in the recurrent hallux valgus with low complication rate and the advantages of a minimally invasive surgery. IV, Retrospective Case Series. Copyright © 2018 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  4. Study on fracture and stress corrosion cracking behavior of casing sour service materials

    International Nuclear Information System (INIS)

    Sequera, C.; Gordon, H.

    2003-01-01

    Present work describes sulphide stress corrosion cracking and fracture toughness tests performed to high strength sour service materials of T-95, C-100 and C-110 oil well tubular grades. P-110 was considered as a reference case, since it is one of the high strength materials included in specification 5CT of American Petroleum Institute, API. Sulphide stress corrosion cracking, impact and fracture toughness values obtained in the tests show that there is a correspondence among them. A decreasing classification order was established, namely C-100, T-95, C-110 and P-110. Special grades steels studied demonstrated a better behavior in the evaluated properties than the reference case material grade: P-110. Results obtained indicate that a higher sulphide stress corrosion cracking resistance is related to a higher toughness. The fracture toughness results evidence the hydrogen influence on reducing the toughness values. (author)

  5. Do Capacity Coupled Electric Fields Accelerate Tibial Stress Fracture Healing?

    National Research Council Canada - National Science Library

    Hoffman, Andrew

    2004-01-01

    A convenience sample based on availability of tibial stress fracture cases a% local Sports Medicine Clinics will be selected over 4 years until forty subjects (20 male, 20 female) have been treated...

  6. Effect of Random Natural Fractures on Hydraulic Fracture Propagation Geometry in Fractured Carbonate Rocks

    Science.gov (United States)

    Liu, Zhiyuan; Wang, Shijie; Zhao, Haiyang; Wang, Lei; Li, Wei; Geng, Yudi; Tao, Shan; Zhang, Guangqing; Chen, Mian

    2018-02-01

    Natural fractures have a significant influence on the propagation geometry of hydraulic fractures in fractured reservoirs. True triaxial volumetric fracturing experiments, in which random natural fractures are created by placing cement blocks of different dimensions in a cuboid mold and filling the mold with additional cement to create the final test specimen, were used to study the factors that influence the hydraulic fracture propagation geometry. These factors include the presence of natural fractures around the wellbore, the dimension and volumetric density of random natural fractures and the horizontal differential stress. The results show that volumetric fractures preferentially formed when natural fractures occurred around the wellbore, the natural fractures are medium to long and have a volumetric density of 6-9%, and the stress difference is less than 11 MPa. The volumetric fracture geometries are mainly major multi-branch fractures with fracture networks or major multi-branch fractures (2-4 fractures). The angles between the major fractures and the maximum horizontal in situ stress are 30°-45°, and fracture networks are located at the intersections of major multi-branch fractures. Short natural fractures rarely led to the formation of fracture networks. Thus, the interaction between hydraulic fractures and short natural fractures has little engineering significance. The conclusions are important for field applications and for gaining a deeper understanding of the formation process of volumetric fractures.

  7. Stress fracture of the medial clavicle secondary to nervous tic

    International Nuclear Information System (INIS)

    Yamada, K.; Sugiura, H.; Suzuki, Y.

    2004-01-01

    The clinical and radiological characteristics of swelling in the region of the medial clavicle may suggest the presence of a neoplastic or inflammatory lesion. This report describes a 27-year-old man with a painful tumor-like lesion over the medial clavicle, which was found to be a stress fracture caused by a nervous tic resulting from mental stress. (orig.)

  8. Increased Oxidative Stress Response in Granulocytes from Older Patients with a Hip Fracture May Account for Slow Regeneration

    Directory of Open Access Journals (Sweden)

    Zhiyong Wang

    2014-01-01

    Full Text Available Proximal femur fracture, a typical fracture of the elderly, is often associated with morbidity, reduced quality of life, impaired physical function and increased mortality. There exists evidence that responses of the hematopoietic microenvironment to fractures change with age. Therefore, we investigated oxidative stress markers and oxidative stress-related MAPK activation in granulocytes from the young and the elderly with and without fractured long bones. Lipid peroxidation levels were increased in the elderly controls and patients. Aged granulocytes were more sensitive towards oxidative stress induced damage than young granulocytes. This might be due to the basally increased expression of SOD-1 in the elderly, which was not further induced by fractures, as observed in young patients. This might be caused by an altered MAPK activation. In aged granulocytes basal p38 and JNK activities were increased and basal ERK1/2 activity was decreased. Following fracture, JNK activity decreased, while ERK1/2 and p38 activities increased in both age groups. Control experiments with HL60 cells revealed that the observed p38 activation depends strongly on age. Summarizing, we observed age-dependent changes in the oxidative stress response system of granulocytes after fractures, for example, altered MAPK activation and SOD-1 expression. This makes aged granulocytes vulnerable to the stress stimuli of the fracture and following surgery.

  9. Proximal supination osteotomy of the first metatarsal for hallux valgus.

    Science.gov (United States)

    Yasuda, Toshito; Okuda, Ryuzo; Jotoku, Tsuyoshi; Shima, Hiroaki; Hida, Takashi; Neo, Masashi

    2015-06-01

    Risk factors for hallux valgus recurrence include postoperative round-shaped lateral edge of the first metatarsal head and postoperative incomplete reduction of the sesamoids. To prevent the occurrence of such conditions, we developed a proximal supination osteotomy of the first metatarsal. Our aim was to describe this novel technique and report the outcomes in this report. Sixty-six patients (83 feet) underwent a distal soft tissue procedure combined with a proximal supination osteotomy. After the proximal crescentic osteotomy, the proximal fragment was pushed medially, and the distal fragment was abducted, and then the distal fragment of the first metatarsal was manually supinated. Outcomes were assessed using the American Orthopaedic Foot & Ankle Society (AOFAS) score and radiographic examinations. The average follow-up duration was 34 (range, 25 to 52) months. The mean AOFAS score improved significantly from 58.0 points preoperatively to 93.8 points postoperatively (P hallux valgus and intermetatarsal angle decreased significantly from 38.6 and 18.0 degrees preoperatively to 11.0 and 7.9 degrees postoperatively, respectively (both, P hallux valgus, defined as a hallux valgus angle ≥ 25 degrees. The rates of occurrence of a positive round sign and incomplete reduction of the sesamoids significantly decreased postoperatively, which may have contributed to the low hallux valgus recurrence rates. We conclude that a proximal supination osteotomy was an effective procedure for correction of hallux valgus and can achieve a low rate of hallux valgus recurrence. Level IV, retrospective case series. © The Author(s) 2015.

  10. Plastic deformation and fracture behavior of zircaloy-2 fuel cladding tubes under biaxial stress

    International Nuclear Information System (INIS)

    Maki, Hideo; Ooyama, Masatosi

    1975-01-01

    Various combinations of biaxial stress were applied on five batches of recrystallized zircaloy-2 fuel cladding tubes with different textures; elongation in both axial and circumferential directions of the specimen was measured continuously up to 5% plastic deformation. The anisotropic theory of plasticity proposed by Hill was applied to the resulting data, and anisotropy constants were obtained through the two media of plastic strain loci and plastic strain ratios. Comparison of the results obtained with the two methods proved that the plastic strain loci provide data that are more effective in predicting quantitatively the plastic deformation behavior of the zircaloy-2 tubes. The anisotropy constants change their value with progress of plastic deformation, and judicious application of the effective stress and effective strain obtained on anisotropic materials will permit the relationship between stress and strain under various biaxialities of stresses to be approximated by the work hardening law. The test specimens used in the plastic deformation experiments were then stressed to fracture under the same combination of biaxial stress as in the proceeding experiments, and the deformation in the fractured part was measured. The result proved that the tilt angle of the c-axis which serves as the index of texture is related to fracture ductility under biaxial stress. Based on this relationship, it was concluded that material with a tilt angle ranging from 10 0 to 15 0 is the most suitable for fuel cladding tubes, from the viewpoint of fracture ductility, at least in the case of unirradiated material. (auth.)

  11. BISPHOSPHONATE INDUCED STRESS FRACTURE OF BILATERAL FEMUR: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Saidapur

    2015-08-01

    Full Text Available Osteoporosis is a common problem affecting people after 4 - 5 decade of life. There are various treatment options available for Osteoporosis and Bisphosphonates are widely used. Bisphosphonates work by blocking osteoclast mediated bone resorption and can be given in oral and injectable forms. R ecent studies have brought to light the risk of sub trochanteric stress fracture secondary to bisphosphonate therapy. Here we are presenting a case with bilateral sub trochanteric fracture following prolonged bisphosphonate therapy

  12. Hydraulic fracturing rock stress measurement at Haestholmen, Finland

    International Nuclear Information System (INIS)

    Ljunggren, C.; Klasson, H.

    1992-12-01

    This report presents hydraulic fracturing measurements in two boreholes located on the Haestholmen island near Loviisa, Finland. The aim of the measurements was to provide stress data, forming input for the design of an underground facility for disposal of low- and medium-level waste as well as future plant decommissioning radioactive waste from the IVO reactor units situated on Haestholmen. The theoretical background to the hydrofracturing method is summarized, as is the equipment and experimental procedures used in the present case. All results obtained are presented and critically discussed. The final stress parameters presented are magnitudes and directions of the maximum and minimum horizontal stresses. Testing was successfully completed according to schedule in both boreholes.(orig.)

  13. A Scaphoid Stress Fracture in a Female Collegiate-Level Shot-Putter and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Jessica M. Kohring

    2016-01-01

    Full Text Available Scaphoid stress fractures are rare injuries that have been described in young, high-level athletes who exhibit repetitive loading with the wrist in extension. We present a case of an occult scaphoid stress fracture in a 22-year-old female Division I collegiate shot-putter. She was successfully treated with immobilization in a thumb spica splint for 6 weeks. Loaded wrist extension activities can predispose certain high-level athletes to sustain scaphoid stress fractures, and a high index of suspicion in this patient population may aid prompt diagnosis and management of this rare injury.

  14. Do Capacitively Coupled Electric Fields Accelerate Tibial Stress Fracture Healing

    National Research Council Canada - National Science Library

    Hoffman, Andrew

    2002-01-01

    A convenience sample based on availability of tibial stress fracture cases at local Sports Medicine Clinics will be selected over 2-3 years until forty subjects (20 male, 20 female) have been treated...

  15. Do Capacitively Coupled Electric Fields Accelerate Tibial Stress Fracture Healing

    National Research Council Canada - National Science Library

    Hoffman, Andrew

    2003-01-01

    A convenience sample based on availability of tibial stress fracture cases at local Sports Medicine Clinics will be selected over 2-3 years until forty subjects (20 male, 20 female) have been treated...

  16. Theoretical and Experimental Investigation of Characteristics of Single Fracture Stress-Seepage Coupling considering Microroughness

    Directory of Open Access Journals (Sweden)

    Shengtong Di

    2017-01-01

    Full Text Available Based on the results of the test among the joint roughness coefficient (JRC of rock fracture, mechanical aperture, and hydraulic aperture proposed by Barton, this paper deduces and proposes a permeability coefficient formula of single fracture stress-seepage coupling considering microroughness by the introduction of effect variables considering the microparticle size and structural morphology of facture surface. Quasi-sandstone fracture of different particle size is made by the laboratory test, and the respective modification is made on the coupled shear-seepage test system of JAW-600 rock. Under this condition, the laboratory test of stress-seepage coupling of fracture of different particle size is carried out. The test results show that, for the different particle-sized fracture surface of the same JRC, the permeability coefficient is different, which means the smaller particle size, the smaller permeability coefficient, and the larger particle size, the larger permeability coefficient; with the increase of cranny hydraulic pressure, the permeability coefficient increases exponentially, and under the same cranny hydraulic pressure, there is relation of power function between the permeability coefficient and normal stress. Meanwhile, according to the theoretical formula, the microroughness coefficient of the fractures with different particle size is obtained by the calculation, and its accuracy and validity are verified by experiments. The theoretical verification values are in good agreement with the measured values.

  17. kISMET: Stress analysis and intermediate-scale hydraulic fracturing at the Sanford Underground Research Facility

    Science.gov (United States)

    Dobson, P. F.; Oldenburg, C. M.; Wu, Y.; Cook, P. J.; Kneafsey, T. J.; Nakagawa, S.; Ulrich, C.; Siler, D. L.; Guglielmi, Y.; Ajo Franklin, J. B.; Rutqvist, J.; Daley, T. M.; Birkholzer, J. T.; Wang, H. F.; Lord, N.; Haimson, B. C.; Sone, H.; Vigilante, P.; Roggenthen, W.; Doe, T.; Lee, M.; Ingraham, M. D.; Huang, H.; Mattson, E.; Johnson, T. C.; Zhou, J.; Zoback, M. D.; Morris, J.; White, J. A.; Johnson, P. A.; Coblentz, D. D.; Heise, J.

    2017-12-01

    In 2015, we established a field test facility at the Sanford Underground Research Facility (SURF), and in 2016 we carried out in situ hydraulic fracturing experiments to characterize the stress field, understand the effects of crystalline rock fabric on fracturing, and gain experience in monitoring using geophysical methods. The kISMET (permeability (k) and Induced Seismicity Management for Energy Technologies) project test site was established in the West Access Drift at the 4850 ft level, 1478 m below ground in phyllite of the Precambrian Poorman Formation. The kISMET team drilled and cored five near-vertical boreholes in a line on 3 m spacing, deviating the two outermost boreholes slightly to create a five-spot pattern around the test borehole centered in the test volume 40 m below the drift invert (floor) at a total depth of 1518 m. Laboratory measurements of core from the center test borehole showed P-wave velocity heterogeneity along each core indicating strong, fine-scale ( 1 cm or smaller) changes in the mechanical properties of the rock. Tensile strength ranges between 3‒7.5 MPa and 5‒12 MPa. Pre-fracturing numerical simulations with a discrete element code were carried out to predict fracture size and magnitude of microseismicity. Field measurements of the stress field were made using hydraulic fracturing, which produced remarkably uniformly oriented fractures suggesting rock fabric did not play a significant role in controlling fracture orientation. Electrical resistivity tomography (ERT) and continuous active seismic source monitoring (CASSM) were deployed in the four monitoring boreholes, and passive seismic accelerometer-based measurements in the West Access Drift were carried out during the generation of a larger fracture (so-called stimulation test). ERT was not able to detect the fracture created, nor did the accelerometers in the drift, but microseismicity was detected for the first (deepest) hydraulic-fracturing stress measurement. Analytical

  18. Resection of the metatarsal head for diabetic foot ulcers.

    Science.gov (United States)

    Wieman, T J; Mercke, Y K; Cerrito, P B; Taber, S W

    1998-11-01

    Diabetic foot ulceration is a worldwide health problem. Approximately 15% of the 10 million diabetic patients in the United States will develop a foot ulceration at some time in their lives. The presence of a foot ulcer in this population is extremely debilitating and dramatically increases the risk of lower extremity amputation, accounting for approximately 67,000 lost limbs each year. Additionally, the costs associated with treating foot ulcers in diabetic patients is a major expense in the overall care of this patient group. An 11-year retrospective study was conducted to evaluate 101 consecutive patients with diabetic ulcers of the forefoot who were treated using resection of the metatarsal head as the primary means of obtaining wound closure. The results indicate that 88% of the ulcers were healed by using this technique, and relatively more rapidly than would be expected when compared with historical norms. Resection of the metatarsal head is a safe and relatively inexpensive procedure that facilitates closure of the lesion, helps to control infection, and prevents countless and costly amputations.

  19. Effect of First Ray Insufficiency and Metatarsal Index on Metatarsalgia in Hallux Valgus.

    Science.gov (United States)

    Slullitel, Gaston; López, Valeria; Calvi, Juan Pablo; Seletti, Maximiliano; Bartolucci, Carla; Pinton, Gustavo

    2016-03-01

    Two concepts have been proposed to explain the etiology of metatarsalgia in hallux valgus patients: First, as the magnitude of hallux valgus increases, there is a mechanical overload of the lesser metatarsals. Second, increased relative lesser metatarsal length is a factor in the development of metatarsalgia. However, there is no current evidence that these structural factors lead to primary metatarsalgia. The purpose of the study was to evaluate the factors associated with metatarsalgia in hallux valgus patients. A cross-sectional study of 121 consecutive adult patients with non-arthritic hallux valgus was carried out. Binary logistic regression was performed to identify the effect of the clinical and demographic factors on the occurrence of metatarsalgia. One hundred twenty-one patients (184 feet) with hallux valgus were analyzed. The median weight was 65 kg (interquartile range 58-72). Metatarsalgia was present in 84 (45.6%) feet. The binary logistic regression showed that lesser toe deformity (OR 2.6, 95% CI 0.2-0.5), gastrocnemius shortening (OR 5.8, 95% CI 2.8-12.3), metatarsal index (OR 0.3, 95% CI 0.2-0.5), and weight (OR 2.5, 95% CI 1.2-5.3) were significantly associated. Metatarsalgia occurs in almost half of hallux valgus patients. It has a multifactorial etiology. Our findings contradict the common theory that both the magnitude of hallux valgus deformity and an increased length of the lesser metatarsals, by themselves, lead to primary metatarsalgia. Metatarsalgia was associated with Achilles shortening, excessive weight, and associated lesser toe deformity. These factors should be addressed in order to treat this disorder adequately. Level III, comparative series. © The Author(s) 2015.

  20. Virtual stress testing of fracture stability in soldiers with severely comminuted tibial fractures.

    Science.gov (United States)

    Petfield, Joseph L; Hayeck, Garry T; Kopperdahl, David L; Nesti, Leon J; Keaveny, Tony M; Hsu, Joseph R

    2017-04-01

    Virtual stress testing (VST) provides a non-invasive estimate of the strength of a healing bone through a biomechanical analysis of a patient's computed tomography (CT) scan. We asked whether VST could improve management of patients who had a tibia fracture treated with external fixation. In a retrospective case-control study of 65 soldier-patients who had tibia fractures treated with an external fixator, we performed VST utilizing CT scans acquired prior to fixator removal. The strength of the healing bone and the amount of tissue damage after application of an overload were computed for various virtual loading cases. Logistic regression identified computed outcomes with the strongest association to clinical events related to nonunion within 2 months after fixator removal. Clinical events (n = 9) were associated with a low tibial strength for compression loading (p fracture patients who can safely resume weight bearing. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:805-811, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  1. Hamate hook stress fracture in a professional bowler: Case report of an unusual causal sport.

    Science.gov (United States)

    How Kit, N; Malherbe, M; Hulet, C

    2017-02-01

    Stress fracture of the hook of the hamate is uncommon and is usually seen in sports involving a club, racquet or bat (i.e., golf, tennis or baseball). It is caused by direct blunt trauma. We report an unusual case of stress fracture with non-union in a 23-year-old professional bowler, probably caused by endogenous constraints, 1 year after the start of symptoms. Treatment consisted of surgical resection of the hook of the hamate. Multimodal imaging of this fracture is reviewed. Copyright © 2016. Published by Elsevier Masson SAS.

  2. Proximal tibia stress fracture with Osteoarthritis of knee - Radiological and functional analysis of one stage TKA with long stem.

    Science.gov (United States)

    Soundarrajan, Dhanasekaran; Rajkumar, Natesan; Dhanasekararaja, Palanisamy; Rajasekaran, Shanmuganathan

    2018-01-01

    Proximal tibia stress fractures with knee osteoarthritis pose a challenging situation. We evaluated the radiological and functional outcome of one-stage total knee arthroplasty (TKA) and long stem for patients with varied grades of knee arthritis and proximal tibia stress fractures.  Methods: We analysed 20 patients from April 2012 to March 2017 with proximal tibia stress fractures associated with knee osteoarthritis of varied grades. Out of 20 patients, five were acute fresh fractures. The mean age was 64 years (range, 52-78) which includes three men and 17 women. Previous surgery in the same limb, rheumatoid arthritis, valgus deformity were excluded. All patients were treated with posterior stabilised TKA with long stem, of which, four patients had screw augmentation for medial tibial bone defect and two patients with malunited fracture at stress fracture site required osteotomy, plating and bone grafting. Two patients had two level stress fracture of tibia in the same leg. The mean follow-up period was 28 (range, 6-60) months. The mean tibiofemoral angle improved from 18.27° varus to 1.8° valgus. The mean knee society score improved from 21.9 (range, -10 to 45) to 82.8 (range, 15-99) [p fractures got united at the last follow-up. One patient had infection and wound dehiscence at six months for which debridement done and had poor functional outcome. TKA with long stem gives excellent outcome, irrespective of severity of arthritis associated with stress fracture. By restoring limb alignment and bypassing the fracture site, it facilitates fracture healing. Early detection and prompt intervention is necessary to prevent the progression to recalcitrant non-union or malunion. © The Authors, published by EDP Sciences, 2018.

  3. [Austin's horizontal V-shaped sliding osteotomy of the metatarsal head [Chevron-osteotomy) in the treatment of hallux valgus].

    Science.gov (United States)

    Steinböck, G

    1996-08-01

    From 1983 to 1995, 1587 patients suffering from hallux abductovalgus were treated with the Austin bunionectomy. The operation consists of a medial exostosis removal, a V-shaped laterally directed displacement osteotomy of the metatarsal head, lateral release and medial reefing of the capsulo-ligamentous structures. Lateral transposition is facilitated by performing a sufficient lateral release consisting of dissection of the lateral metatarsophalangeal ligament and separation of the adductor tendon from the base of the phalanx and the lateral sesamoid. In the case of intermetatarsal angles greater than 15 degrees, the metatarsal-sesamoid ligament is also severed just above the lateral sesamoid. The periosteum is stripped in a limited fashion dorsally and toward the plantar, leaving its insertion at the metatarsal head intact. After this procedure, reposition of the metatarsal head onto the sesamoids is usually possible and is maintained by reconstruction of the medial metatarsal-sesamoid ligament. In the author's own research material, metatarsophalangeal angles larger than 50 degrees and intermetatarsal angles of over 20 degrees could be corrected. Pronation of the toe is usually corrected by tenotomy of the abductor tendon near the base of the phalanx. Avascular necrosis is extremely rare with a careful operative technique. In our extensive research material, four cases of AVN were recognized. Provided there is free motion of the joint (60-0-20), mild radiological signs of osteoarthritis are no contraindication for the operation. Even in the aged, good results can be achieved provided there are no trophic problems. The Austin bunionectomy has proved to be a versatile method for treating bunion problems. The possibility of transposing the metatarsal head laterally, toward the plantar, proximally and distally by altering the direction of the osteotomy, as well as tilting it medially or laterally, has made this osteotomy an invaluable tool for addressing various

  4. Non-linear hydrotectonic phenomena: Part I - fluid flow in open fractures under dynamical stress loading

    International Nuclear Information System (INIS)

    Archambeau, C.B.

    1994-01-01

    A fractured solid under stress loading (or unloading) can be viewed as behaving macroscopically as a medium with internal, hidden, degrees of freedom, wherein changes in fracture geometry (i.e. opening, closing and extension) and flow of fluid and gas within fractures will produce major changes in stresses and strains within the solid. Likewise, the flow process within fractures will be strongly coupled to deformation within the solid through boundary conditions on the fracture surfaces. The effects in the solid can, in part, be phenomenologically represented as inelastic or plastic processes in the macroscopic view. However, there are clearly phenomena associated with fracture growth and open fracture fluid flows that produce effects that can not be described using ordinary inelastic phenomenology. This is evident from the fact that a variety of energy release phenomena can occur, including seismic emissions of previously stored strain energy due to fracture growth, release of disolved gas from fluids in the fractures resulting in enhanced buoyancy and subsequent energetic flows of gas and fluids through the fracture system which can produce raid extension of old fractures and the creation of new ones. Additionally, the flows will be modulated by the opening and closing of fractures due to deformation in the solid, so that the flow process is strongly coupled to dynamical processes in the surrounding solid matrix, some of which are induced by the flow itself

  5. The impact of different aperture distribution models and critical stress criteria on equivalent permeability in fractured rocks

    DEFF Research Database (Denmark)

    Bisdom, Kevin; Bertotti, Giovanni; Nick, Hamid

    2016-01-01

    Predicting equivalent permeability in fractured reservoirs requires an understanding of the fracture network geometry and apertures. There are different methods for defining aperture, based on outcrop observations (power law scaling), fundamental mechanics (sublinear length-aperture scaling...... in the fraction of open fractures. For the applied stress conditions, Coulomb predicts that 50% of the network is critically stressed, compared to 80% for Barton-Bandis peak shear. The impact of the fracture network on equivalent permeability depends on the matrix hydraulic properties, as in a low...

  6. Macro-mesoscopic Fracture and Strength Character of Pre-cracked Granite Under Stress Relaxation Condition

    Science.gov (United States)

    Liu, Junfeng; Yang, Haiqing; Xiao, Yang; Zhou, Xiaoping

    2018-05-01

    The fracture characters are important index to study the strength and deformation behavior of rock mass in rock engineering. In order to investigate the influencing mechanism of loading conditions on the strength and macro-mesoscopic fracture character of rock material, pre-cracked granite specimens are prepared to conduct a series of uniaxial compression experiments. For parts of the experiments, stress relaxation tests of different durations are also conducted during the uniaxial loading process. Furthermore, the stereomicroscope is adopted to observe the microstructure of the crack surfaces of the specimens. The experimental results indicate that the crack surfaces show several typical fracture characters in accordance with loading conditions. In detail, some cleavage fracture can be observed under conventional uniaxial compression and the fractured surface is relatively rough, whereas as stress relaxation tests are attached, relative slip trace appears between the crack faces and some shear fracture starts to come into being. Besides, the crack faces tend to become smoother and typical terrace structures can be observed in local areas. Combining the macroscopic failure pattern of the specimens, it can be deduced that the duration time for the stress relaxation test contributes to the improvement of the elastic-plastic strain range as well as the axial peak strength for the studied material. Moreover, the derived conclusion is also consistent with the experimental and analytical solution for the pre-peak stage of the rock material. The present work may provide some primary understanding about the strength character and fracture mechanism of hard rock under different engineering environments.

  7. Residual stress state in pipe cut ring specimens for fracture toughness testing

    Energy Technology Data Exchange (ETDEWEB)

    Damjanovic, Darko [J.J. Strossmayer Univ. of Osijek, Slavonski Brod (Croatia). Mechanical Engineering Faculty; Kozak, Drazan [Zagreb Univ. (Croatia). Dept. for Mechanical Design; Marsoner, Stefan [Materials Center, Leoben (Austria).; Gubeljak, Nenad [Maribor Univ. (Slovenia). Chair of Mechanics

    2017-07-01

    Thin-walled pipes are not suitable for measuring fracture toughness parameters of vital importance because longitudinal crack failure is the most common failure mode in pipes. This is due to the impossibility to manufacture standard specimens for measuring fracture toughness, such as SENB or CT specimens, from the thin wall of the pipe. Previous works noticed this problem, but until now, a good and convenient solution has not been found or developed. To overcome this problem, very good alternative solution was proposed, the so-called pipe ring notched bend specimen (PRNB) [1-5]. Until now, only the idealized geometry PRNB specimen is analyzed, i. e., a specimen which is not cut out from an actual pipe but produced from steel plate. Based on that, residual stresses are neglected along with the imperfections in geometry (elliptical and eccentricity). The aim of this research is to estimate the residual stress state(s) in real pipes used in the boiler industry produced by hot rolling technique. These types of pipes are delivered only in normalized condition, but not stress relieved. Therefore, there are residual stresses present due to the manufacturing technique, but also due to uneven cooling after the production process. Within this paper, residual stresses are estimated by three methods: the incremental hole drilling method (IHMD), X-ray diffraction (XRD) and the splitting method (SM). Knowing the residual stress state in the ring specimen, it is possible to assess their impact on fracture toughness measured on the corresponding PRNB specimen(s).

  8. Residual stress state in pipe cut ring specimens for fracture toughness testing

    International Nuclear Information System (INIS)

    Damjanovic, Darko; Kozak, Drazan; Marsoner, Stefan; Gubeljak, Nenad

    2017-01-01

    Thin-walled pipes are not suitable for measuring fracture toughness parameters of vital importance because longitudinal crack failure is the most common failure mode in pipes. This is due to the impossibility to manufacture standard specimens for measuring fracture toughness, such as SENB or CT specimens, from the thin wall of the pipe. Previous works noticed this problem, but until now, a good and convenient solution has not been found or developed. To overcome this problem, very good alternative solution was proposed, the so-called pipe ring notched bend specimen (PRNB) [1-5]. Until now, only the idealized geometry PRNB specimen is analyzed, i. e., a specimen which is not cut out from an actual pipe but produced from steel plate. Based on that, residual stresses are neglected along with the imperfections in geometry (elliptical and eccentricity). The aim of this research is to estimate the residual stress state(s) in real pipes used in the boiler industry produced by hot rolling technique. These types of pipes are delivered only in normalized condition, but not stress relieved. Therefore, there are residual stresses present due to the manufacturing technique, but also due to uneven cooling after the production process. Within this paper, residual stresses are estimated by three methods: the incremental hole drilling method (IHMD), X-ray diffraction (XRD) and the splitting method (SM). Knowing the residual stress state in the ring specimen, it is possible to assess their impact on fracture toughness measured on the corresponding PRNB specimen(s).

  9. [Double Osteotomy of the First Metatarsal for Treatment of Juvenile Hallux Valgus Deformity - Our Experience].

    Science.gov (United States)

    Jochymek, J; Peterková, T

    2016-01-01

    The aim of the study was to evaluate the mid-term results in a group of selected patients undergoing corrective surgery for juvenile hallux valgus, using double osteotomy of the first metatarsal. The group included eight patients, seven girls and one boy, with a more severe form of this deformity treated by double osteotomy of the first metatarsal between 2010 and 2013. The indication for corrective surgery was serious pain when walking; all patients had previously undergone conservative treatment with no effect. All patients had pre-operative clinical examination, the affected foot was X-rayed with the patient standing and radiographic assessments of the intermetatarsal and hallux valgus angles were made. The evaluation of treatment outcomes was based on the scoring system of the American Orthopaedic Foot and Ankle Society (AOFAS) and X-ray images of the foot. The average follow-up was 37 months. Post-operatively, none of the patients reported pain while walking, only two of them experienced pain during sports activities. The average post-operative AOFAS score was 92 points. Both the intermetatarsal angle and the hallux valgus angle improved after surgery in all patients, with two reporting only mild hallux valgus deformity. One patient showed postoperative restriction of motion at the first metatarsophalangeal joint. This was the only complication recorded in association with the surgery. Almost all authors dealing with the treatment of hallux valgus deformity primarily prefer conservative therapy. However, this treatment is usually not very effective in severe forms of the disorder. Surgical management is indicated in symptomatic patients or in those with severe juvenile hallux valgus deformity. In paediatric patients it is necessary to respect the presence of an epiphyseal growth plate in the first proximal metatarsal and therefore it is often preferred to use distal first metatarsal osteotomy. At our department, Mitchell's osteotomy for hallux valgus deformity

  10. Hydraulic fracturing stress measurements at Yucca Mountain, Nevada, and relationship to the regional stress field

    International Nuclear Information System (INIS)

    Stock, J.M.; Healy, J.H.; Hickman, S.H.; Zoback, M.D.

    1985-01-01

    Hydraulic fracturing stress measurements and acoustic borehole televiewer logs were run in holes USW G-1 and USW G-2 at Yucca Mountain as part of the Nevada Nuclear Waste Storage Investigations for the U. S. Department of Energy. Eight tests in the saturated zone, at depths from 646 to 1288 m, yielded values of the least horizontal stress S/sub h/ that are considerably lower than the vertical principal stress S/sub v/. In tests for which the greatest horizontal principal stress S/sub H/ could be determined, it was found to be less than S/sub v/, indicating a normal faulting stress regime. The borehole televiewer logs showed the presence of long (in excess of 10 m), vertical, drilling-induced fractures in the first 300 m below the water table. These are believed to form by the propagation of small preexisting cracks under the excess downhole fluid pressures (up to 5.2 MPa) applied during drilling. The presence of these drilling-induced hydrofractures provides further confirmation of the low value of the least horizontal stresses. A least horizontal principal stress direction of N60 0 W--N65 0 W is indicated by the orientation of the drilling-induced hydrofractures (N25 0 E--N30 0 E), and the orientation of stress-induced well bore breakouts in the lower part of USW G-2 (N65 0 W). This direction is in good agreement with indicators of stress direction from elsewhere at the Nevada Test Site. The observed stress magnitudes and directions were examined for the possibility of slip on preexisting faults. Using these data, the Coulomb criterion for frictional sliding suggests that for coefficients of friction close to 0.6, movement on favorably oriented faults could be expected

  11. Stress Fractures of the Distal Femur Involving Small Nonossifying Fibromas in Young Athletes.

    Science.gov (United States)

    Robertson, Michael; Gilley, Jasen; Nicholas, Richard

    2016-11-01

    Small nonossifying fibromas (ie, fibrocortical defects) are incidental findings commonly seen on radiographs of young patients evaluated for extremity pain or sport-related trauma. Although pathological fractures have been reported in larger lesions, the subcentimeter, intracortical defects are not generally thought to predispose to pathological fractures. The authors report on 2 young athletes who presented with knee pain after initiating conditioning exercise programs (cross-training). Both were diagnosed with transverse metaphyseal stress fractures involving fibrous cortical defects of the distal femur. Initial radiographs were interpreted without evidence of fractures. However, subsequent magnetic resonance imaging was informative, suggesting that magnetic resonance imaging may have value in identifying potential stress reactions in young athletes. In addition, subsequent plain radiographs of both patients showed subperiosteal new bone formation in these nondisplaced fractures, suggesting that serial radiographs and close clinical follow-up are warranted for patients with persistent symptoms. The authors propose that, in the appropriate clinical setting, the presence of a small nonossifying fibroma may be a clinical indication that further evaluation is needed when plain radiographs show normal findings, as the defect could be an unrecognized area of fracture initiation. [Orthopedics. 2016; 39(6):e1197-e1200.]. Copyright 2016, SLACK Incorporated.

  12. Coulomb stress change during and after tensile fracture opening in a geothermal reservoir

    NARCIS (Netherlands)

    Urpi, L.; Blöcher, G.; Zimmermann, G.; Wees, J.D. van; Fokker, P.

    2013-01-01

    Stress shadowing and the ratio of shear to normal stress in the rock surrounding a newly created tensile fracture are investigated. Shearing on plane of weakness near the stimulated volume can be inhibited or promoted by change in poro- and thermo-elastic stress, while pore pressure increase tends

  13. Influence of stress-induced deformations on observed water flow in fractures at the Climax granitic stock

    International Nuclear Information System (INIS)

    Wilder, D.G.

    1987-06-01

    Three examples of stress-induced displacement influence on fracture-dominated hydrology were noted in drifts 1400 ft below surface in granite. Seepage into drifts was limited to portions of shears near a fault zone. No water entered the drifts from the fault itself, although its orientation relative to Basin and Range extension is favorable for fracture opening. Localization of seepage appears to result from excavation block motion that increased apertures of the shear zones in contrast to the fault where asperities had been destroyed by earlier shearing thus minimizing aperture increases. Seepage was also noted, in an adjoining drift, from a set of shallow-dip healed fractures that intersected the rib, and from vertical fractures that increased the crown. The restricted location of this seepage apparently was a result of shear opening of the joints that occurred because of cantilevered support of tabular rock between joints. Interpretation of paleostresses based on joint chronologies and orientations indicates that sets subjected to shear stresses at a time when normal stresses were low contained mineral infilling. Sets subjected to shear stresses at a time when the normal stresses were significant had minimal mineral infilling. 8 refs., 7 figs

  14. Fundamental differences in axial and appendicular bone density in stress fractured and uninjured Royal Marine recruits--a matched case-control study.

    Science.gov (United States)

    Davey, Trish; Lanham-New, Susan A; Shaw, Anneliese M; Cobley, Rosalyn; Allsopp, Adrian J; Hajjawi, Mark O R; Arnett, Timothy R; Taylor, Pat; Cooper, Cyrus; Fallowfield, Joanne L

    2015-04-01

    Stress fracture is a common overuse injury within military training, resulting in significant economic losses to the military worldwide. Studies to date have failed to fully identify the bone density and bone structural differences between stress fractured personnel and controls due to inadequate adjustment for key confounding factors; namely age, body size and physical fitness; and poor sample size. The aim of this study was to investigate bone differences between male Royal Marine recruits who suffered a stress fracture during the 32 weeks of training and uninjured control recruits, matched for age, body weight, height and aerobic fitness. A total of 1090 recruits were followed through training and 78 recruits suffered at least one stress fracture. Bone mineral density (BMD) was measured at the lumbar spine (LS), femoral neck (FN) and whole body (WB) using Dual X-ray Absorptiometry in 62 matched pairs; tibial bone parameters were measured using peripheral Quantitative Computer Tomography in 51 matched pairs. Serum C-terminal peptide concentration was measured as a marker of bone resorption at baseline, week-15 and week-32. ANCOVA was used to determine differences between stress fractured recruits and controls. BMD at the LS, WB and FN sites was consistently lower in the stress fracture group (Pstress fracture recruits and controls were evident in all slices of the tibia, with the most prominent differences seen at the 38% tibial slice. There was a negative correlation between the bone cross-sectional area and BMD at the 38% tibial slice. There was no difference in serum CTx concentration between stress fracture recruits and matched controls at any stage of training. These results show evidence of fundamental differences in bone mass and structure in stress fracture recruits, and provide useful data on bone risk factor profiles for stress fracture within a healthy military population. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  15. Oncogenic osteomalacia presenting as bilateral stress fractures of the tibia

    International Nuclear Information System (INIS)

    Ohashi, Kenjirou; Ohnishi, Takeshi; Ishikawa, Tohru; Tani, Haruo; Uesugi, Keisuke; Takagi, Masayuki

    1999-01-01

    We report on a patient with bilateral stress fractures of the tibia who subsequently showed classic biochemical features of oncogenic osteomalacia. Conventional radiographs were normal. MR imaging revealed symmetric, bilateral, band-like low-signal lesions perpendicular to the medial cortex of the tibiae and corresponding to the only lesions subsequently seen on the bone scan. A maxillary sinus lesion was subsequently detected and surgically removed resulting in prompt alleviation of symptoms and normalization of hypophosphatemia and low 1,25-(OH) 2 vitamin D 3 . The lesion was pathologically diagnosed as a hemangiopericytoma-like tumor. Patients with oncogenic osteomalacia may present with stress fractures limited to the tibia, as seen in athletes. The clue to the real diagnosis lies in paying close attention to the serum phosphate levels, especially in patients suffering generalized symptoms of weakness and not given to unusual physical activity. (orig.)

  16. Bilateral Stress Fractures of the Femoral Neck from Renal Osteomalacia: A Case Report

    Directory of Open Access Journals (Sweden)

    S Sengupta

    2008-04-01

    Full Text Available A rare case of spontaneous bilateral stress fractures of femoral neck leading to coxa vara in a young female with history of chronic renal disease and secondary osteomalacia is described. Once the underlying disease was controlled, the fracture was treated by valgus osteotomy with good result.

  17. Minimally Invasive Distal Metatarsal Osteotomy for Mild-to-Moderate Hallux Valgus Deformity

    Directory of Open Access Journals (Sweden)

    Yu-Chuan Lin

    2009-08-01

    Full Text Available Minimally invasive surgery has recently been introduced for foot and ankle surgery, and hallux valgus surgery is no exception. The purpose of our study was to analyze the early results and to present our experience of minimally invasive distal metatarsal osteotomy in correcting mild-to-moderate hallux valgus deformities. Between September 2005 and December 2006, 31 consecutive patients (47 feet with mild-to-moderate hallux valgus deformities underwent minimally invasive distal metatarsal osteotomies. The clinical and radiographic outcomes were assessed. The satisfaction rate was 90.32%. The mean total American Orthopedic Foot and Ankle Society halluxmetatarsophalangeal-interphalangeal scale was 92.7 points. Complications included two (4.26% episodes of stiffness, six (12.77% episodes of pin tract infection, and one (2.13% deep infection. There were no cases with nonunion, malunion, overcorrection, transfer metatarsalgia or osteonecrosis. On weight-bearing anteroposterior foot radiographs, the mean hallux valgus angle and first intermetatarsal angle corrections were 11.8° and 6.3°, respectively, which is a statistically significant difference (p < 0.001 between the preoperative and postoperative status. Here, minimally invasive distal metatarsal osteotomy was associated with good satisfaction, functional improvement and low complication rates. This technique offers an effective, safe and simple way to treat hallux valgus with a first intermetatarsal angle less than 15°.

  18. Effect of surgical shoes on brake response time after first metatarsal osteotomy?a prospective cohort study

    OpenAIRE

    Dammerer, Dietmar; Braito, Matthias; Biedermann, Rainer; Ban, Michael; Giesinger, Johannes; Haid, Christian; Liebensteiner, Michael C.; Kaufmann, Gerhard

    2016-01-01

    Background The aim of this study is to assess patients? driving ability when wearing surgical shoes following right-sided first metatarsal osteotomy. Methods From August 2013 to August 2015, 42 consecutive patients (mean age 54.5?years) with right-sided hallux valgus deformity underwent first metatarsal osteotomy. Patients were tested for brake response time (BRT) 1?day preoperatively (control run) and at 2 and 6?weeks postoperatively. Two different types of foot orthosis were investigated. B...

  19. Outcome of limb fracture repair in rabbits: 139 cases (2007-2015).

    Science.gov (United States)

    Sasai, Hiroshi; Fujita, Daisuke; Seto, Eiko; Denda, Yuki; Imai, Yutaro; Okamoto, Kanako; Okamura, Kensaku; Furuya, Masaru; Tani, Hiroyuki; Sasai, Kazumi

    2018-02-15

    OBJECTIVE To evaluate outcome of limb fracture repair in rabbits. DESIGN Retrospective case series. ANIMALS 139 client-owned rabbits with limb fractures treated between 2007 and 2015. PROCEDURES Medical records were reviewed for information on fracture location, fracture treatment, and time to fracture healing. RESULTS 25 rabbits had fractures involving the distal aspects of the limbs (ie, metacarpal or metatarsal bones, phalanges, and calcaneus or talus). Fractures were treated in 23 of these 25 rabbits (external coaptation, n = 17; external skeletal fixation, 4; and intramedullary pinning, 2) and healed in all 23, with a median healing time of 28 days (range, 20 to 45 days). One hundred ten rabbits had long bone fractures, and fractures were treated in 100 of the 110 (external skeletal fixation, n = 89; bone plating, 1; intramedullary pinning, 3; and external coaptation, 7). The percentage of fractures that healed was significantly lower for open (14/18) than for closed (26/26) tibial fractures and was significantly lower for femoral (19/26) and treated humeral (4/6) fractures than for radial (23/24) or closed tibial (26/26) fractures. Micro-CT was used to assess fracture realignment during external skeletal fixator application and to evaluate fracture healing. CONCLUSIONS AND CLINICAL RELEVANCE The prognosis for rabbits with limb fractures was good, with fractures healing in most rabbits following fracture repair (109/123). Micro-CT was useful in assessing fracture realignment and evaluating fracture healing.

  20. Role of MRI in hip fractures, including stress fractures, occult fractures, avulsion fractures

    International Nuclear Information System (INIS)

    Nachtrab, O.; Cassar-Pullicino, V.N.; Lalam, R.; Tins, B.; Tyrrell, P.N.M.; Singh, J.

    2012-01-01

    MR imaging plays a vital role in the diagnosis and management of hip fractures in all age groups, in a large spectrum of patient groups spanning the elderly and sporting population. It allows a confident exclusion of fracture, differentiation of bony from soft tissue injury and an early confident detection of fractures. There is a spectrum of MR findings which in part is dictated by the type and cause of the fracture which the radiologist needs to be familiar with. Judicious but prompt utilisation of MR in patients with suspected hip fractures has a positive therapeutic impact with healthcare cost benefits as well as social care benefits.

  1. Effect of Stress State on Fracture Features

    Science.gov (United States)

    Das, Arpan

    2018-02-01

    Present article comprehensively explores the influence of specimen thickness on the quantitative estimates of different ductile fractographic features in two dimensions, correlating tensile properties of a reactor pressure vessel steel tested under ambient temperature where the initial crystallographic texture, inclusion content, and their distribution are kept unaltered. It has been investigated that the changes in tensile fracture morphology of these steels are directly attributable to the resulting stress-state history under tension for given specimen dimensions.

  2. Atypical femoral neck stress fracture in a marathon runner: a case report and literature review.

    LENUS (Irish Health Repository)

    2012-02-01

    BACKGROUND: Femoral neck stress fractures are relatively rare and may present as sports-related injuries. The presentation is variable, and prompt diagnosis facilitates the earliest return to pre-morbid functional activity levels. Delayed detection may precipitate femoral non-union or avascular necrosis, resulting in long-term functional deficit. AIMS: We present the case of a basicervical femoral neck stress fracture occurring in a 23-year-old marathon runner. The pathophysiology and practical management issues related to this unusual injury pattern are discussed. CONCLUSION: The growing interest in amateur athletic activities should raise the index of suspicion for stress fractures of the femoral neck in healthy adults with atypical hip pain. Increased levels of patient education and physician awareness can reduce the incidence of long-term morbidity in cases of this unusual sports-related injury.

  3. Surgical management of proximal splint bone fractures in the horse

    International Nuclear Information System (INIS)

    Peterson, P.R.; Pascoe, J.R.; Wheat, J.D.

    1987-01-01

    Fractures of Metacarpal and Metatarsal II and IV (the splint bones) were treated in 283 horses over an 11 year period. In 21 cases the proximal portion of the fractured bone was stabilized with metallic implants. One or more cortical bone screws were used in 11 horses, and bone plates were applied in 11 horses. One horse received both treatments. Complications of screw fixation included bone failure, implant failure, radiographic lucency around the screws, and proliferative new bone at the ostectomy site. Only two of the horses treated with screw fixation returned to their intended use. Complications of plate fixation included partial fixation failure (backing out of screws), wound drainage, and proliferative bony response around the plate. Six of the 11 horses treated by plate fixation returned to their intended use. The authors recommend consideration of plate fixation techniques for repair of fractures in the proximal third of the splint bone

  4. Simulation of three-dimensional tectonic stress fields and quantitative prediction of tectonic fracture within the Damintun Depression, Liaohe Basin, northeast China

    Science.gov (United States)

    Guo, Peng; Yao, Leihua; Ren, Desheng

    2016-05-01

    Tectonic fractures are important factors that influence oil and natural gas migration and accumulation within "buried hill" reservoirs. To obtain a quantitative forecast of the development and distribution of reservoir fractures in the Damintun Depression, we analyzed the characteristics of regional structural evolution and paleotectonic stress field setting. A reasonable geological model of the research area was built based on an interpretation of the geological structure, a test for rock mechanics, and experiment on acoustic emission. Thereafter, a three-dimensional paleotectonic stress field during the Yanshan movement was simulated by the finite element method. Rock failure criterion and comprehensive evaluation coefficient of fractures were used to determine the quantitative development of fractures and predict zones that are prone to fracture development. Under an intense Yanshan movement, high stress strength is distributed in the south and northeast parts of the study area, where stress is extremely high. The fracture development zones are mainly controlled by the tectonic stress field and typically located in the same areas as those of high maximum principal and shear stresses. The predicted areas with developed fractures are consistent with the wells with high fracture linear density and in locations with high-producing oil and gas wells.

  5. Metatarsal lengthening in congenital brachymetatarsia: one-stage lengthening versus lengthening by callotasis.

    Science.gov (United States)

    Choi, I H; Chung, M S; Baek, G H; Cho, T J; Chung, C Y

    1999-01-01

    We retrospectively reviewed and compared the outcomes of 15 one-stage metatarsal lengthenings with intercalary bone graftings in 10 patients with those of nine metatarsal lengthenings by callotasis in five patients younger than 15 years. In the one-stage lengthening group, the diaphyseal osteotomy site was gradually distracted intraoperatively for 20-30 min to relax the surrounding soft tissues. In the callotasis group, lengthening was achieved with mini-Orthofix M-100. There was little difference in the outcomes between the two groups in terms of length gain, percentage increase, and complications. However, the period to achieve bony consolidation was longer in the callotasis group (2.7 months/cm) than in the one-stage lengthening group (1.5 months/cm). No case of neurovascular impairment was found in both groups.

  6. Bone geometry, strength, and muscle size in runners with a history of stress fracture.

    Science.gov (United States)

    Popp, Kristin L; Hughes, Julie M; Smock, Amanda J; Novotny, Susan A; Stovitz, Steven D; Koehler, Scott M; Petit, Moira A

    2009-12-01

    Our primary aim was to explore differences in estimates of tibial bone strength, in female runners with and without a history of stress fractures. Our secondary aim was to explore differences in bone geometry, volumetric density, and muscle size that may explain bone strength outcomes. A total of 39 competitive distance runners aged 18-35 yr, with (SFX, n = 19) or without (NSFX, n = 20) a history of stress fracture were recruited for this cross-sectional study. Peripheral quantitative computed tomography (XCT 3000; Orthometrix, White Plains, NY) was used to assess volumetric bone mineral density (vBMD, mg x mm(-3)), bone area (ToA, mm(2)), and estimated compressive bone strength (bone strength index (BSI) = ToA x total volumetric density (ToD(2))) at the distal tibia (4%). Total (ToA, mm(2)) and cortical (CoA, mm(2)) bone area, cortical vBMD, and estimated bending strength (strength-strain index (SSIp), mm(3)) were measured at the 15%, 25%, 33%, 45%, 50%, and 66% sites. Muscle cross-sectional area (MCSA) was measured at the 50% and 66% sites. Participants in the SFX group had significantly smaller (7%-8%) CoA at the 45%, 50%, and 66% sites (P stress fracture. However, the lower strength was appropriate for the smaller muscle size, suggesting that interventions to reduce stress fracture risk might be aimed at improving muscle size and strength.

  7. Stress analysis and optimization of Nd:YAG pulsed laser processing of notches for fracture splitting of a C70S6 connecting rod

    International Nuclear Information System (INIS)

    Kou, Shuqing; Gao, Yan; Zhao, Yong; Lin, Baojun

    2017-01-01

    The pulsed laser pre-processing of a notch as the fracture initiation source for the splitting process is the key mechanism of an advanced fracture splitting technology for C70S6 connecting rods. This study investigated the stress field of Nd:YAG pulsed laser grooving, which affects the rapid fracture initiation at the notch root and the controlled crack extension in the critical fracture splitting quality, to improve manufacturing quality. Thermal elastic-plastic incremental theory was applied to build the finite element analysis model of the stress field of pulsed laser grooving for fracture splitting based on the Rotary-Gauss body heat source. The corresponding numerical simulation of the stress field was conducted. The changes and distributions of the stress during pulsed laser grooving were examined, the influence rule of the primary technological parameters on the residual stress was analyzed, and the analysis results were validated by the corresponding cutting experiment. Results showed that the residual stress distribution was concentrated in the Heat-affected zone (HAZ) near the fracture splitting notch, which would cause micro-cracks in the HAZ. The stress state of the notch root in the fracture initiation direction was tensile stress, which was beneficial to the fracture initiation and the crack rapid extension in the subsequent fracture splitting process. However, the uneven distribution of the stress could lead to fracture splitting defects, and thus the residual stress should be lowered to a reasonable range. Decreasing the laser pulse power, increasing the processing speed, and lowering the pulse width can lower the residual stress. Along with the actual production, the reasonable main technological parameters were obtained.

  8. Stress analysis and optimization of Nd:YAG pulsed laser processing of notches for fracture splitting of a C70S6 connecting rod

    Energy Technology Data Exchange (ETDEWEB)

    Kou, Shuqing; Gao, Yan; Zhao, Yong; Lin, Baojun [Jilin University, Changchun (China)

    2017-05-15

    The pulsed laser pre-processing of a notch as the fracture initiation source for the splitting process is the key mechanism of an advanced fracture splitting technology for C70S6 connecting rods. This study investigated the stress field of Nd:YAG pulsed laser grooving, which affects the rapid fracture initiation at the notch root and the controlled crack extension in the critical fracture splitting quality, to improve manufacturing quality. Thermal elastic-plastic incremental theory was applied to build the finite element analysis model of the stress field of pulsed laser grooving for fracture splitting based on the Rotary-Gauss body heat source. The corresponding numerical simulation of the stress field was conducted. The changes and distributions of the stress during pulsed laser grooving were examined, the influence rule of the primary technological parameters on the residual stress was analyzed, and the analysis results were validated by the corresponding cutting experiment. Results showed that the residual stress distribution was concentrated in the Heat-affected zone (HAZ) near the fracture splitting notch, which would cause micro-cracks in the HAZ. The stress state of the notch root in the fracture initiation direction was tensile stress, which was beneficial to the fracture initiation and the crack rapid extension in the subsequent fracture splitting process. However, the uneven distribution of the stress could lead to fracture splitting defects, and thus the residual stress should be lowered to a reasonable range. Decreasing the laser pulse power, increasing the processing speed, and lowering the pulse width can lower the residual stress. Along with the actual production, the reasonable main technological parameters were obtained.

  9. Proximal tibia stress fracture with Osteoarthritis of knee − Radiological and functional analysis of one stage TKA with long stem

    Science.gov (United States)

    Soundarrajan, Dhanasekaran; Rajkumar, Natesan; Dhanasekararaja, Palanisamy; Rajasekaran, Shanmuganathan

    2018-01-01

    Introduction: Proximal tibia stress fractures with knee osteoarthritis pose a challenging situation. We evaluated the radiological and functional outcome of one-stage total knee arthroplasty (TKA) and long stem for patients with varied grades of knee arthritis and proximal tibia stress fractures.  Methods: We analysed 20 patients from April 2012 to March 2017 with proximal tibia stress fractures associated with knee osteoarthritis of varied grades. Out of 20 patients, five were acute fresh fractures. The mean age was 64 years (range, 52–78) which includes three men and 17 women. Previous surgery in the same limb, rheumatoid arthritis, valgus deformity were excluded. All patients were treated with posterior stabilised TKA with long stem, of which, four patients had screw augmentation for medial tibial bone defect and two patients with malunited fracture at stress fracture site required osteotomy, plating and bone grafting. Two patients had two level stress fracture of tibia in the same leg. Results: The mean follow-up period was 28 (range, 6–60) months. The mean tibiofemoral angle improved from 18.27° varus to 1.8° valgus. The mean knee society score improved from 21.9 (range, −10 to 45) to 82.8 (range, 15–99) [p fractures got united at the last follow-up. One patient had infection and wound dehiscence at six months for which debridement done and had poor functional outcome. Conclusion: TKA with long stem gives excellent outcome, irrespective of severity of arthritis associated with stress fracture. By restoring limb alignment and bypassing the fracture site, it facilitates fracture healing. Early detection and prompt intervention is necessary to prevent the progression to recalcitrant non-union or malunion. PMID:29667926

  10. Do stress fractures induce hypertrophy of the grafted fibula? A report of three cases received free vascularized fibular graft treatment for tibial defects.

    Science.gov (United States)

    Qi, Yong; Sun, Hong-Tao; Fan, Yue-Guang; Li, Fei-Meng; Lin, Zhou-Sheng

    2016-06-01

    The presence of large segmental defects of the diaphyseal bone is challenging for orthopedic surgeons. Free vascularized fibular grafting (FVFG) is considered to be a reliable reconstructive procedure. Stress fractures are a common complication following this surgery, and hypertrophy is the main physiological change of the grafted fibula. The exact mechanism of hypertrophy is not completely known. To the best of our knowledge, no studies have examined the possible relationship between stress fractures and hypertrophy. We herein report three cases of patients underwent FVFG. Two of them developed stress fractures and significant hypertrophy, while the remaining patient developed neither stress fractures nor significant hypertrophy. This phenomenon indicates that a relationship may exist between stress fractures and hypertrophy of the grafted fibula, specifically, that the presence of a stress fracture may initiate the process of hypertrophy.

  11. Use of Pulsing Electromagnetic Fields for the Treatment of Pelvic Stress Fractures Among Female Soldiers

    National Research Council Canada - National Science Library

    Jones, D

    1995-01-01

    .... Pulsing electromagnetic fields (PEMFs)have been shown to speed the healing of non-union fractures and we have used them successfully to treat stress fractures in the lower limbs. All women at Ft...

  12. Two-View Gravity Stress Imaging Protocol for Nondisplaced Type II Supination External Rotation Ankle Fractures: Introducing the Gravity Stress Cross-Table Lateral View.

    Science.gov (United States)

    Boffeli, Troy J; Collier, Rachel C; Gervais, Samuel J

    Assessing ankle stability in nondisplaced Lauge-Hansen supination external rotation type II injuries requires stress imaging. Gravity stress mortise imaging is routinely used as an alternative to manual stress imaging to assess deltoid integrity with the goal of differentiating type II from type IV injuries in cases without a posterior or medial fracture. A type II injury with a nondisplaced fibula fracture is typically treated with cast immobilization, and a type IV injury is considered unstable and often requires operative repair. The present case series (two patients) highlights a standardized 2-view gravity stress imaging protocol and introduces the gravity stress cross-table lateral view. The gravity stress cross-table lateral view provides a more thorough evaluation of the posterior malleolus owing to the slight external rotation and posteriorly directed stress. External rotation also creates less bony overlap between the tibia and fibula, allowing for better visualization of the fibula fracture. Gravity stress imaging confirmed medial-sided injury in both cases, confirming the presence of supination external rotation type IV or bimalleolar equivalent fractures. Open reduction and internal fixation was performed, and both patients achieved radiographic union. No further treatment was required at 21 and 33 months postoperatively. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Weightbearing vs Gravity Stress Radiographs for Stability Evaluation of Supination-External Rotation Fractures of the Ankle.

    Science.gov (United States)

    Seidel, Angela; Krause, Fabian; Weber, Martin

    2017-07-01

    Isolated lateral malleolar fractures may result from a supination-external rotation (SER) injury of the ankle. Stable fractures maintain tibiotalar congruence due to competent medial restraints and can be treated nonoperatively with excellent functional results and long-term prognosis. Stability might be assessed with either stress radiographs or weightbearing radiographs. A consecutive series of patients with closed SER fractures (presumed AO 44-B1) were prospectively enrolled from 2008 to 2015. Patients with clearly unstable fractures (medial clear space more than 7 mm) on the initial nonweightbearing radiograph were excluded and operated on. All other patients were examined with a gravity stress and a weightbearing anteroposterior radiograph. Borderline instability of the fracture was assumed when the medial clear space was 4 to 7 mm. Those were treated nonoperatively. Of 104 patients with isolated lateral malleolar fractures of the SER type, 14 patients were treated operatively because of clear instability (displacement) on the initial radiographs. Of the nonoperative patients, 44 patients demonstrated borderline instability on the gravity stress but stability on the weightbearing radiograph ("gravity borderline"); the remaining 46 were stable in both tests ("gravity stable"). At an average follow-up of 23 months, no significant differences were seen in the American Orthopaedic Foot & Ankle Society hindfoot score (92 points gravity-borderline group vs 93 points gravity-unstable group), the Foot Functional Index score (11 vs 10 points), the Short Form 36 (SF-36) physical component (86 vs 85 points), and SF-36 mental component (84 vs 81 points). Radiographically, all fractures had healed with anatomic congruity of the ankle. Weightbearing radiographs provided a reliable basis to decide about stability and nonoperative treatment in isolated lateral malleolar fractures of the SER type with excellent clinical and radiographic outcome at short-term follow-up. Gravity

  14. Dry fracture method for simultaneous measurement of in-situ stress state and material properties

    International Nuclear Information System (INIS)

    Serata, S.; Oka, S.; Kikuchi, S.

    1996-01-01

    Based on the dry fracture principle, a computerized borehole probe has been developed to measure stress state and material properties, simultaneously. The probe is designed to obtain a series of measurements in a continuing sequence along a borehole length, without any interruptive measures, such as resetting packers, taking indentation of borehole wall, overcoming, etc. The new dry fracture probe for the single fracture method is designed to overcome the difficulties posed by its ancestor which was based on the double fracture method. The accuracy of the single fracture method is confirmed by a close agreement with the theory, FE modeling and laboratory testing

  15. Oncogenic osteomalacia presenting as bilateral stress fractures of the tibia

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Kenjirou; Ohnishi, Takeshi; Ishikawa, Tohru [Department of Radiology, St. Marianna University Hospital, Kanagawa (Japan); Tani, Haruo [Department of Internal Medicine III, St. Marianna University Hospital, Kawasaki City, Kanagawa (Japan); Uesugi, Keisuke [Department of Otolaryngology, St. Marianna University Hospital, Kawasaki City, Kanagawa (Japan); Takagi, Masayuki [Department of Pathology, St. Marianna University Hospital, Kawasaki City, Kanagawa (Japan)

    1999-01-01

    We report on a patient with bilateral stress fractures of the tibia who subsequently showed classic biochemical features of oncogenic osteomalacia. Conventional radiographs were normal. MR imaging revealed symmetric, bilateral, band-like low-signal lesions perpendicular to the medial cortex of the tibiae and corresponding to the only lesions subsequently seen on the bone scan. A maxillary sinus lesion was subsequently detected and surgically removed resulting in prompt alleviation of symptoms and normalization of hypophosphatemia and low 1,25-(OH){sub 2} vitamin D{sub 3}. The lesion was pathologically diagnosed as a hemangiopericytoma-like tumor. Patients with oncogenic osteomalacia may present with stress fractures limited to the tibia, as seen in athletes. The clue to the real diagnosis lies in paying close attention to the serum phosphate levels, especially in patients suffering generalized symptoms of weakness and not given to unusual physical activity. (orig.) With 4 figs., 6 refs.

  16. Surgical Management of Proximal Interphalangeal Joint Repetitive Stress Epiphyseal Fracture Nonunion in Elite Sport Climbers.

    Science.gov (United States)

    El-Sheikh, Yasser; Lutter, Chris; Schoeffl, Isabelle; Schoeffl, Volker; Flohe, Sascha

    2017-11-14

    Repetitive stress fracture of the middle phalanx epiphysis is an injury specific to elite adolescent sport climbers. As sport climbing becomes increasingly popular in younger age groups, an increased number of these injuries have been reported in recent years. To date, treatment of these fractures has been nonsurgical, with strict rest and physiotherapy prescribed until fracture union. However, when these patients present in a delayed fashion with an established nonunion, nonsurgical treatment may fail, leading to disabling chronic pain and/or digital deformity in some cases. In this article, we present 2 cases of surgical treatment for finger middle phalanx repetitive stress epiphyseal fracture nonunion, using a percutaneous spot drilling epiphysiodesis technique. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  17. Ground reaction forces and bone parameters in females with tibial stress fracture.

    Science.gov (United States)

    Bennell, Kim; Crossley, Kay; Jayarajan, Jyotsna; Walton, Elizabeth; Warden, Stuart; Kiss, Z Stephen; Wrigley, Tim

    2004-03-01

    Tibial stress fracture is a common overuse running injury that results from the interplay of repetitive mechanical loading and bone strength. This research project aimed to determine whether female runners with a history of tibial stress fracture (TSF) differ in ground reaction force (GRF) parameters during running, regional bone density, and tibial bone geometry from those who have never sustained a stress fracture (NSF). Thirty-six female running athletes (13 TSF; 23 NSF) ranging in age from 18 to 44 yr were recruited for this cross-sectional study. The groups were well matched for demographic, training, and menstrual parameters. A force platform measured selected GRF parameters (peak and time to peak for vertical impact and active forces, and horizontal braking and propulsive forces) during overground running at 4.0 m.s.(-1). Lumbar spine, proximal femur, and distal tibial bone mineral density were assessed by dual energy x-ray absorptiometry. Tibial bone geometry (cross-sectional dimensions and areas, and second moments of area) was calculated from a computerized tomography scan at the junction of the middle and distal thirds. There were no significant differences between the groups for any of the GRF, bone density, or tibial bone geometric parameters (P > 0.05). Both TSF and NSF subjects had bone density levels that were average or above average compared with a young adult reference range. Factor analysis followed by discriminant function analysis did not find any combinations of variables that differentiated between TSF and NSF groups. These findings do not support a role for GRF, bone density, or tibial bone geometry in the development of tibial stress fractures, suggesting that other risk factors were more important in this cohort of female runners.

  18. Modeling and stress analyses of a normal foot-ankle and a prosthetic foot-ankle complex.

    Science.gov (United States)

    Ozen, Mustafa; Sayman, Onur; Havitcioglu, Hasan

    2013-01-01

    Total ankle replacement (TAR) is a relatively new concept and is becoming more popular for treatment of ankle arthritis and fractures. Because of the high costs and difficulties of experimental studies, the developments of TAR prostheses are progressing very slowly. For this reason, the medical imaging techniques such as CT, and MR have become more and more useful. The finite element method (FEM) is a widely used technique to estimate the mechanical behaviors of materials and structures in engineering applications. FEM has also been increasingly applied to biomechanical analyses of human bones, tissues and organs, thanks to the development of both the computing capabilities and the medical imaging techniques. 3-D finite element models of the human foot and ankle from reconstruction of MR and CT images have been investigated by some authors. In this study, data of geometries (used in modeling) of a normal and a prosthetic foot and ankle were obtained from a 3D reconstruction of CT images. The segmentation software, MIMICS was used to generate the 3D images of the bony structures, soft tissues and components of prosthesis of normal and prosthetic ankle-foot complex. Except the spaces between the adjacent surface of the phalanges fused, metatarsals, cuneiforms, cuboid, navicular, talus and calcaneus bones, soft tissues and components of prosthesis were independently developed to form foot and ankle complex. SOLIDWORKS program was used to form the boundary surfaces of all model components and then the solid models were obtained from these boundary surfaces. Finite element analyses software, ABAQUS was used to perform the numerical stress analyses of these models for balanced standing position. Plantar pressure and von Mises stress distributions of the normal and prosthetic ankles were compared with each other. There was a peak pressure increase at the 4th metatarsal, first metatarsal and talus bones and a decrease at the intermediate cuneiform and calcaneus bones, in

  19. Treatment of stress fracture of the olecranon in throwing athletes with internal fixation through a small incision

    Directory of Open Access Journals (Sweden)

    Fujioka Hiroyuki

    2012-12-01

    Full Text Available Abstract The present study is a report of retrospective case series of stress fracture of the olecranon. Six patients presented posterior elbow pain in throwing in baseball and softball, but fracture was not diagnosed in radiographs. We detected stress fracture of the olecranon using computed tomographic (CT scan and treated the patient with internal fixation with a headless cannulated double threaded screw through a small skin incision. All patients returned to competitive level without elbow complaints after the operation. When throwing athletes present with unusual posterior elbow pain and no significant findings on radiographs, a CT scan examination should be performed. We recommend surgical treatment of internal fixation with a screw through a small skin incision, as a good option for stress fracture of the olecranon in order to allow early return to sports activity in competitive athletes.

  20. Plantar flaps based on perforators of the plantar metatarsal/common digital arteries.

    Science.gov (United States)

    Valentin, Georgescu Alexandru; Rodica, Matei Ileana; Manuel, Llusa

    2014-09-01

    Because of the unique characteristics of its integument, the affirmation "replacing like with like" becomes more than evident in the reconstruction of defects of the ultraspecialized plantar skin. But, the paucity of local resources, and especially in the forefoot, transforms this attempt in a very challenging problem. Many techniques, including skin grafts and various types of flaps were used in the management of defects in the forefoot. We present a new useful flap in the reconstruction of skin defects in the forefoot, based on small perforator vessels originating either from the plantar metatarsal arteries or plantar common digital arteries. Starting with June 2011, this flap was performed, as plantar transposition perforator flap, plantar propeller flap, or plantar propeller perforator plus flap, in seven patients with ulcers over the plantar forefoot. During a follow-up of 7 to 17 months (mean, 9.8 months), the local evolution regarding flap integration, pain, relapse, sensitive recovery, donor site, and footwear quality was analyzed. We registered a 100% survival rate of the flaps, with delayed healing in only one case. The gait resumption was possible after 6 weeks in all cases. This new flap, based on small perforator vessels from the plantar metatarsal or common digital arteries, and which provides a good, stable, and sensory recovery, seems to be a promising method in the reconstruction of plantar skin defects over the metatarsal heads. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  1. First inter metatarsal (IM) angles in Nigerians and their relationship ...

    African Journals Online (AJOL)

    Background: No age is immune to the deformity known as Hallux valgus as it has been proven that 50% of adults developed it during adolescence, while 40% of juveniles developed it before the age of 10.5 years. Aim: To determine from radiographs the normal value of the first inter metatarsal (IM) angle and to establish if ...

  2. Predisposing Risk Factors and Stress Fractures in Division I Cross Country Runners.

    Science.gov (United States)

    Giffin, Kaci L; Knight, Kathy B; Bass, Martha A; Valliant, Melinda W

    2017-11-11

    The purpose of this study was to explore factors associated with increased stress fractures in collegiate cross country runners. Participants in this study were 42 male and female cross country runners at a Division I university. Each athlete completed a questionnaire regarding smoking status, vitamin/mineral intake, previous stress fracture history, birth control usage, menstrual status, and demographic information. Nutritional assessment via a 3-day food record and measurements of whole body, lumbar spine, and hip bone mineral densities (BMD) were also conducted on each athlete. Results indicated that 40% of the female and 35% of the male runners reported a history of stress fracture, and that all of these did not meet the recommended daily energy intake or adequate intakes for calcium or Vitamin D required for their amount of training. Two-tailed t-test found statistically higher incidences of lumbar spine BMD in males and females whose daily calcium and Vitamin D intakes were below minimum requirements as well as for women whose caloric intake was below the required level. When data on the lumbar spine was evaluated, 31% of participants (31.8% of the male and 30% of the female runners) were identified as having osteopenia and 4.8% with osteoporosis. Results warrant a need for future longitudinal studies.

  3. Prediction of minimum UO2 particle size based on thermal stress initiated fracture model

    International Nuclear Information System (INIS)

    Corradini, M.

    1976-08-01

    An analytic study was employed to determine the minimum UO 2 particle size that could survive fragmentation induced by thermal stresses in a UO 2 -Na Fuel Coolant Interaction (FCI). A brittle fracture mechanics approach was the basis of the study whereby stress intensity factors K/sub I/ were compared to the fracture toughness K/sub IC/ to determine if the particle could fracture. Solid and liquid UO 2 droplets were considered each with two possible interface contact conditions; perfect wetting by the sodium or a finite heat transfer coefficient. The analysis indicated that particles below the range of 50 microns in radius could survive a UO 2 -Na fuel coolant interaction under the most severe temperature conditions without thermal stress fragmentation. Environmental conditions of the fuel-coolant interaction were varied to determine the effects upon K/sub I/ and possible fragmentation. The underlying assumptions of the analysis were investigated in light of the analytic results. It was concluded that the analytic study seemed to verify the experimental observations as to the range of the minimum particle size due to thermal stress fragmentation by FCI. However the method used when the results are viewed in light of the basic assumptions indicates that the analysis is crude at best, and can be viewed as only a rough order of magnitude analysis. The basic complexities in fracture mechanics make further investigation in this area interesting but not necessarily fruitful for the immediate future

  4. Plate Versus Intramedullary Nail Fixation of Anterior Tibial Stress Fractures: A Biomechanical Study.

    Science.gov (United States)

    Markolf, Keith L; Cheung, Edward; Joshi, Nirav B; Boguszewski, Daniel V; Petrigliano, Frank A; McAllister, David R

    2016-06-01

    Anterior midtibial stress fractures are an important clinical problem for patients engaged in high-intensity military activities or athletic training activities. When nonoperative treatment has failed, intramedullary (IM) nail and plate fixation are 2 surgical options used to arrest the progression of a fatigue fracture and allow bone healing. A plate will be more effective than an IM nail in preventing the opening of a simulated anterior midtibial stress fracture from tibial bending. Controlled laboratory study. Fresh-frozen human tibias were loaded by applying a pure bending moment in the sagittal plane. Thin transverse saw cuts, 50% and 75% of the depth of the anterior tibial cortex, were created at the midtibia to simulate a fatigue fracture. An extensometer spanning the defect was used to measure the fracture opening displacement (FOD) before and after the application of IM nail and plate fixation constructs. IM nails were tested without locking screws, with a proximal screw only, and with proximal and distal screws. Plates were tested with unlocked bicortical screws (standard compression plate) and locked bicortical screws; both plate constructs were tested with the plate edge placed 1 mm from the anterior tibial crest (anterior location) and 5 mm posterior to the crest. For the 75% saw cut depth, the mean FOD values for all IM nail constructs were 13% to 17% less than those for the saw cut alone; the use of locking screws had no significant effect on the FOD. The mean FOD values for all plate constructs were significantly less than those for all IM nail constructs. The mean FOD values for all plates were 28% to 46% less than those for the saw cut alone. Anterior plate placement significantly decreased mean FOD values for both compression and locked plate constructs, but the mean percentage reductions for locked and unlocked plates were not significantly different from each other for either plate placement. The percentage FOD reductions for all plate

  5. Histological variations in myoepithelial cells and arrectores pilorum muscles among caudal, metatarsal and preorbital glands in Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884).

    Science.gov (United States)

    Ozaki, Nobuo; Suzuki, Masatsugu; Ohtaishi, Noriyuki

    2004-03-01

    The morphological characteristics of myoepithelial cells and arrectores pilorum muscles were investigated in caudal, metatarsal and preorbital glands of Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) using immunohistochemistry for alpha-smooth muscle actin. In the metatarsal, preorbital and general skin glands, myoepithelial cell layers continuously embraced the secretory epithelium, while in the caudal gland, discontinuous myoepithelial cell rows surrounded the apocrine tubules. There was a trend that the widths of the myoepithelial cells of the caudal and preorbital glands appeared to be thinner than those of the metatarsal and general skin glands. In the metatarsal gland, the arrectores pilorum muscles were highly developed and considerably larger than those in other skin glands.

  6. Estimation of In Situ Stresses with Hydro-Fracturing Tests and a Statistical Method

    Science.gov (United States)

    Lee, Hikweon; Ong, See Hong

    2018-03-01

    At great depths, where borehole-based field stress measurements such as hydraulic fracturing are challenging due to difficult downhole conditions or prohibitive costs, in situ stresses can be indirectly estimated using wellbore failures such as borehole breakouts and/or drilling-induced tensile failures detected by an image log. As part of such efforts, a statistical method has been developed in which borehole breakouts detected on an image log are used for this purpose (Song et al. in Proceedings on the 7th international symposium on in situ rock stress, 2016; Song and Chang in J Geophys Res Solid Earth 122:4033-4052, 2017). The method employs a grid-searching algorithm in which the least and maximum horizontal principal stresses ( S h and S H) are varied, and the corresponding simulated depth-related breakout width distribution as a function of the breakout angle ( θ B = 90° - half of breakout width) is compared to that observed along the borehole to determine a set of S h and S H having the lowest misfit between them. An important advantage of the method is that S h and S H can be estimated simultaneously in vertical wells. To validate the statistical approach, the method is applied to a vertical hole where a set of field hydraulic fracturing tests have been carried out. The stress estimations using the proposed method were found to be in good agreement with the results interpreted from the hydraulic fracturing test measurements.

  7. Fracture network growth for prediction of fracture characteristics and connectivity in tight reservoir rocks

    NARCIS (Netherlands)

    Barnhoorn, A.; Cox, S.F.

    2012-01-01

    Fracturing experiments on very low-porosity dolomite rocks shows a difference in growth of fracture networks by stress-driven fracturing and fluid-driven fracturing. Stress-driven fracture growth, in the absence of fluid pressure, initially forms fractures randomly throughout the rocks followed by

  8. X-ray fractography by using synchrotron radiation source. Residual stress distribution just beneath fatigue fracture surface

    International Nuclear Information System (INIS)

    Akita, Koichi; Yoshioka, Yasuo; Suzuki, Hiroshi; Sasaki, Toshihiko

    2000-01-01

    The residual stress distributions just beneath the fatigue fracture surface were measured using synchrotron radiation with three different wavelengths, i.e., three different penetration depths. The residual stress distributions were estimated from three kinds of diffraction data by the following process. First, a temporary residual stress distribution in the depth direction is assumed. Theoretical 2θ-sin 2 ψ diagrams for each wavelength, where each has a different penetration depth, are calculated by the cosψ method developed by one of the authors. The sum total of the differences between the theoretical and experimental values of the diffraction angle in 2θ-sin 2 ψ diagrams is calculated. This total value is minimized by changing the assumed stress distribution by the quasi-Newton optimization method. Finally, optimized 2θ-sin 2 ψ diagrams for each penetration depth and detailed stress distribution are determined. The true surface residual stress is obtained from this stress distribution. No effect of load ratio R (= P min /P max ) on the residual stresses of the fatigue fracture surfaces in low-carbon steels was observed when the sin 2 ψ method was used for stress measurement. However, the residual stresses became higher with increasing R when these were measured by the proposed method. On the basis of this, the stress intensity factor range, ΔK, can be estimated from the residual stress on the fatigue fracture surface. (author)

  9. Longitudinal stress fractures of the tibia: diagnosis by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Umans, H.R.; Kaye, J.J.

    1996-01-01

    Previous works describe magnetic resonance (MR) imaging characteristics of stress fractures. This report focusses on MR imaging of longitudinal stress fractures of the tibia. Six cases are presented in which a longitudinal linear abnormal marrow signal was detected in the middle and distal parts of the tibial shaft. Five patients were imaged using a 1.5 Tesla MR unit. Axial, sagittal and coronal T1 and T2-weighted or fat suppressed proton density fast spin echo images were obtained in all but one patient. One patient was imaged using a 0.5 Tesla MR unit with axial and coronal T1- and T2-weighted sequences. Initial conventional radiographs seen at clinical presentation were interpreted as normal in all cases. Two patients underwent radionuclide bone scan, and one patient was imaged with CT prior to MR imaging. In each instance, MR imaging demonstrated linear marrow signal abnormalities orientated along the long axis of the tibial shaft. Endosteal and periosteal callus was identified on axial images. In all cases, MR imaging clearly demonstrated a fracture extending through one cortex with abnormal signal in both the marrow cavity as well as adjacent soft tissues indicating edema. (orig./MG)

  10. Longitudinal stress fractures of the tibia: diagnosis by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Umans, H.R. [Dept. of Radiology, Albert Einstein Coll. of Medicine and Montefiore Medical Center, Bronx, NY (United States); Kaye, J.J. [The Hospital for Special Surgery, New York, NY (United States)

    1996-05-01

    Previous works describe magnetic resonance (MR) imaging characteristics of stress fractures. This report focusses on MR imaging of longitudinal stress fractures of the tibia. Six cases are presented in which a longitudinal linear abnormal marrow signal was detected in the middle and distal parts of the tibial shaft. Five patients were imaged using a 1.5 Tesla MR unit. Axial, sagittal and coronal T1 and T2-weighted or fat suppressed proton density fast spin echo images were obtained in all but one patient. One patient was imaged using a 0.5 Tesla MR unit with axial and coronal T1- and T2-weighted sequences. Initial conventional radiographs seen at clinical presentation were interpreted as normal in all cases. Two patients underwent radionuclide bone scan, and one patient was imaged with CT prior to MR imaging. In each instance, MR imaging demonstrated linear marrow signal abnormalities orientated along the long axis of the tibial shaft. Endosteal and periosteal callus was identified on axial images. In all cases, MR imaging clearly demonstrated a fracture extending through one cortex with abnormal signal in both the marrow cavity as well as adjacent soft tissues indicating edema. (orig./MG)

  11. Completed Ulnar Shaft Stress Fracture in a Fast-Pitch Softball Pitcher.

    Science.gov (United States)

    Wiltfong, Roger E; Carruthers, Katherine H; Popp, James E

    2017-03-01

    Stress fractures of the upper extremity have been previously described in the literature, yet reports of isolated injury to the ulna diaphysis or olecranon are rare. The authors describe a case involving an 18-year-old fast-pitch softball pitcher. She presented with a long history of elbow and forearm pain, which was exacerbated during a long weekend of pitching. Her initial physician diagnosed her as having forearm tendinitis. She was treated with nonsurgical means including rest, anti-inflammatory medications, therapy, and kinesiology taping. She resumed pitching when allowed and subsequently had an acute event immediately ceasing pitching. She presented to an urgent care clinic that evening and was diagnosed as having a complete ulnar shaft fracture subsequently needing surgical management. This case illustrates the need for a high degree of suspicion for ulnar stress fractures in fast-pitch soft-ball pitchers with an insidious onset of unilateral forearm pain. Through early identification and intervention, physicians may be able to reduce the risk of injury progression and possibly eliminate the need for surgical management. [Orthopedics. 2017; 40(2):e360-e362.]. Copyright 2016, SLACK Incorporated.

  12. Bone Geometry as a Predictor of Tissue Fragility and Stress Fracture Risk

    Science.gov (United States)

    2004-10-01

    eferences ........................................................................ 11 A ppendices ...School of Medicine, New York NY Stress fractures occur among persons with normal bones, no acute injury, and are most common among elite runners and

  13. Additional Stress And Fracture Mechanics Analyses Of Pressurized Water Reactor Pressure Vessel Nozzles

    International Nuclear Information System (INIS)

    Walter, Matthew; Yin, Shengjun; Stevens, Gary; Sommerville, Daniel; Palm, Nathan; Heinecke, Carol

    2012-01-01

    In past years, the authors have undertaken various studies of nozzles in both boiling water reactors (BWRs) and pressurized water reactors (PWRs) located in the reactor pressure vessel (RPV) adjacent to the core beltline region. Those studies described stress and fracture mechanics analyses performed to assess various RPV nozzle geometries, which were selected based on their proximity to the core beltline region, i.e., those nozzle configurations that are located close enough to the core region such that they may receive sufficient fluence prior to end-of-life (EOL) to require evaluation of embrittlement as part of the RPV analyses associated with pressure-temperature (P-T) limits. In this paper, additional stress and fracture analyses are summarized that were performed for additional PWR nozzles with the following objectives: To expand the population of PWR nozzle configurations evaluated, which was limited in the previous work to just two nozzles (one inlet and one outlet nozzle). To model and understand differences in stress results obtained for an internal pressure load case using a two-dimensional (2-D) axi-symmetric finite element model (FEM) vs. a three-dimensional (3-D) FEM for these PWR nozzles. In particular, the ovalization (stress concentration) effect of two intersecting cylinders, which is typical of RPV nozzle configurations, was investigated. To investigate the applicability of previously recommended linear elastic fracture mechanics (LEFM) hand solutions for calculating the Mode I stress intensity factor for a postulated nozzle corner crack for pressure loading for these PWR nozzles. These analyses were performed to further expand earlier work completed to support potential revision and refinement of Title 10 to the U.S. Code of Federal Regulations (CFR), Part 50, Appendix G, Fracture Toughness Requirements, and are intended to supplement similar evaluation of nozzles presented at the 2008, 2009, and 2011 Pressure Vessels and Piping (PVP

  14. Practical application of fracture mechanics with consideration of multiaxiality of stress state to degraded nuclear piping

    International Nuclear Information System (INIS)

    Kussmaul, K.; Blind, D.; Herter, K.H.; Eisele, U.; Schuler, X.

    1995-01-01

    Within the scope of a research project nuclear piping components (T-branches and elbows) with dimensions like the primary coolant lines of PWR plants were investigated. In addition to the experimental full scale tests, extensive numerical calculations by means of the finite element method (FEM) as well as fracture mechanics analyses were performed. The applicability of these methods was verified by comparison with the experimental results. The calculation of fracture mechanics parameters as well as the calculated component stress enabled a statement on crack initiation. The failure behavior could be evaluated by means of the multiaxiality of stress state in the ligament (gradient of the quotient of the multiaxiality of stress state q). With respect to practical application on other pressurized components it is shown how to use the procedure (e.g. in a LBB analysis). A quantitative assessment with regard to crack initiation is possible by comparison of the effective crack initiation value J ieff with the calculated component stress. If the multiaxiality of stress state and the q gradient in the ligament of the fracture ligament of the fracture mechanics specimen and the pressurized component to be evaluated is comparable a quantitative assessment is possible as for crack extension and maximum load. If there is no comparability of the gradients a qualitative assessment is possible for the failure behavior

  15. Transfer of the second to the first metatarsal ray in a case of lawn mower injury: a case report.

    Science.gov (United States)

    Sassu, Paolo; Tsai, Tsu Min

    2009-01-01

    The medial longitudinal arch of the foot plays a major role for a physiologic transfer of the load from the heel to the forefoot during walking and running. Traumatic amputation that involve either the great toe or the whole first metatarsal bone can lead to collapse of the medial longitudinal arch, overload of the metatarsal heads, and painful callus formation. If replant of the amputated part is not possible or has failed, it is advisable to reconstruct the medial longitudinal arch in order to re-establish a functional transfer of the load in the foot. We present a case of a young lady who suffered from traumatic amputation at the distal third of the first metatarsal. Replantation failed due to the severity of the initial injury. Despite a good coverage of the defect with a lateral arm flap, the patient developed a painful plantar callus underneath the amputated stump. The adjacent second metatarsal ray was then raised as a pedicled flap including bone and soft tissues and transferred to the first ray in order to reconstruct a physiologic medial longitudinal arch. The patient had excellent functional results with no recurrence of the callus. (c) 2008 Wiley-Liss, Inc.

  16. Tension band plating of a nonunion anterior tibial stress fracture in an athlete.

    Science.gov (United States)

    Merriman, Jarrad A; Villacis, Diego; Kephart, Curtis J; Rick Hatch, George F

    2013-07-01

    The authors present a rare technique of tension band plating of the anterior tibia in the setting of a nonunion stress fracture. Surgical management with an intramedullary nail is a viable and proven option for treating such injuries. However, in treating elite athletes, legitimate concerns exist regarding the surgical disruption of the extensor mechanism and the risk of anterior knee pain associated with intramedullary nail use. The described surgical technique demonstrates the use of tension band plating as an effective treatment of delayed union and nonunion anterior tibial stress fractures in athletes without the potential risks of intramedullary nail insertion. Copyright 2013, SLACK Incorporated.

  17. A study on the fractures of iodine induced stress corrosion cracking of new zirconium alloys

    International Nuclear Information System (INIS)

    Peng Qian; Zhao Wenjin; Li Weijun; Tang Zhenghua; Heng Xuemei

    2005-10-01

    The morphology and chemical compositions of I-SCC fractures of new zirconium alloys were investigated by SEM and EDXA. The feature on fracture surface for I-SCC samples, such as corrosion products, the secondary cracking, intergranular cracking and pseudo-cleavage transgranular cracking, have been observed. And the fluting, the typical characteristic of I-SCC also has been found. Intergranular cracking is visible at crack initiation stage and transgranular cracking is distinguished at crack propagation stage. The corrosion products are mainly composed of Zr and O; and I can be detected on the local pseudocleavage zone. The most of grooves on the fractures of relieved-stress annealing samples are parallel with the roll plane. The intergranular cracking in relieved-stress annealing samples is not obvious. When the test temperature increases, the activity of iodine increases and the stress on crack tip is easier to be released, thus the corrosion products on fracture also increase and intergranular cracking is visible. The partial pressure of iodine influents the thickness of corrosion products, and intergranular cracking is easier to be found when iodine partial pressure is high enough. (authors)

  18. Effectiveness of various isometric exercises at improving bone strength in cortical regions prone to distal tibial stress fractures.

    Science.gov (United States)

    Florio, C S

    2018-06-01

    A computational model was used to compare the local bone strengthening effectiveness of various isometric exercises that may reduce the likelihood of distal tibial stress fractures. The developed model predicts local endosteal and periosteal cortical accretion and resorption based on relative local and global measures of the tibial stress state and its surface variation. Using a multisegment 3-dimensional leg model, tibia shape adaptations due to 33 combinations of hip, knee, and ankle joint angles and the direction of a single or sequential series of generated isometric resultant forces were predicted. The maximum stress at a common fracture-prone region in each optimized geometry was compared under likely stress fracture-inducing midstance jogging conditions. No direct correlations were found between stress reductions over an initially uniform circular hollow cylindrical geometry under these critical design conditions and the exercise-based sets of active muscles, joint angles, or individual muscle force and local stress magnitudes. Additionally, typically favorable increases in cross-sectional geometric measures did not guarantee stress decreases at these locations. Instead, tibial stress distributions under the exercise conditions best predicted strengthening ability. Exercises producing larger anterior distal stresses created optimized tibia shapes that better resisted the high midstance jogging bending stresses. Bent leg configurations generating anteriorly directed or inferiorly directed resultant forces created favorable adaptations. None of the studied loads produced by a straight leg was significantly advantageous. These predictions and the insight gained can provide preliminary guidance in the screening and development of targeted bone strengthening techniques for those susceptible to distal tibial stress fractures. Copyright © 2018 John Wiley & Sons, Ltd.

  19. Risk Stratification of Stress Fractures and Prediction of Return to Duty

    Science.gov (United States)

    2015-12-01

    SUBJECT TERMS bone microarchitecture, HRpQCT, race, gender , sex, bone mineral density, vBMD, bone geometry, stress fracture 16. SECURITY...are collaborating with local sports medicine physicians, coaches, and athletic trainers to continue recruiting effectively (Task 3, objective 3). We

  20. On the fracture of human dentin: Is it stress- orstrain-controlled?

    Energy Technology Data Exchange (ETDEWEB)

    Nalla, R.K.; Kinney, J.H.; Ritchie, R.O.

    2006-02-01

    Despite substantial clinical interest in the fracture resistance of human dentin, there is little mechanistic information in archival literature that can be usefully used to model such fracture. In fact, although the fracture event indent in, akin to other mineralized tissues like bone, is widely believed to be locally strain-controlled, there has never been any scientific proof to support this belief. The present study seeks to address this issue through the use of a novel set of in vitro experiments in Hanks' balanced salt solution involving a double-notched bend test geometry, which is designed to discern whether the critical failure events involved in the onset of fracture are locally stress- or strain-controlled. Such experiments are further used to characterize the notion of ''plasticity'' in dentin and the interaction of cracks with the salient microstructural features. It is observed that fracture in dentin is indeed locally strain-controlled and that the presence of dentinal tubules does not substantially affect this process of crack initiation and growth. The results presented are believed to be critical steps in the development of a micromechanical model for the fracture of human dentin that takes into consideration the influence of both the microstructure and the local failure mode.

  1. Lag screw fixation of dorsal cortical stress fractures of the third metacarpal bone in 116 racehorses.

    Science.gov (United States)

    Jalim, S L; McIlwraith, C W; Goodman, N L; Anderson, G A

    2010-10-01

    The effectiveness and best method to manage dorsal cortical stress fractures is not clear. This study was performed to evaluate the success of lag screw fixation of such fractures in a population of Thoroughbred racehorses. Lag screw fixation of dorsal cortical stress fractures is an effective surgical procedure allowing racehorses to return to their preoperative level of performance. The records of 116 racehorses (103 Thoroughbreds) admitted to Equine Medical Centre, California between 1986 and 2008 were assessed. Information obtained from medical records included subject details, limb(s) affected, fracture configuration, length of screw used in repair and presence of concurrent surgical procedures performed. Racing performance was evaluated relative to these factors using Fisher's exact test and nonparametric methods with a level of significance of Phorses, 83% raced preoperatively and 83% raced post operatively, with 63% having ≥5 starts. There was no statistically significant association between age, gender, limb affected, fracture configuration or presence of concurrent surgery and likelihood of racing post operatively or of having 5 or more starts. The mean earnings per start and the performance index for the 3 races following surgery were lower compared to the 3 races prior to surgery; however, 29 and 45% of horses either improved or did not change their earnings per start and performance index, respectively. Data show that lag screw fixation is successful at restoring ability to race in horses suffering from dorsal cortical stress fractures. © 2010 EVJ Ltd.

  2. Micromechanical studies of cyclic creep fracture under stress controlled loading

    DEFF Research Database (Denmark)

    van der Giessen, Erik; Tvergaard, Viggo

    1996-01-01

    is based on numerical unit cell analyses for a planar polycrystal model with the grains and grain boundaries modeled individually, in order to investigate the interactions between the mechanisms involved and to account for the build-up of residual stress fields during cycling. The behaviour of a limiting......This paper deals with a study of intergranular failure by creep cavitation under stress-controlled cyclic loading conditions. Loading is assumed to be slow enough that diffusion and creep mechanisms (including grain boundary sliding) dominate, leading to intergranular creep fracture. This study...

  3. Anatomical variations in dorsal metatarsal arteries with surgical significance: A cadaveric study

    Directory of Open Access Journals (Sweden)

    Preeti Shivshankar Awari

    2017-01-01

    Full Text Available Introduction: Based on angiosome concept to revascularize a particular artery, the microvascular and reconstructive surgeons must know the anatomy and variations in the arteries in that specific region of the body to achieve better results. Nowadays, dorsal metatarsal artery (DMTA perforator flaps and toe grafts are becoming popular which also demand adequate information about normal anatomy and variants in these arteries for fruitful results. Materials and Methods: The authors studied normal anatomy and variations in the origin of DMTAs in 50 lower extremities of 25 embalmed cadavers. Results: The authors found many variations as the absence of DMTAs, origin of the DMTA from the deep plantar arch. The places wherever the arcuate artery was absent the lateral tarsal artery gave rise to dorsal metatarsal arteries. Conclusion: Being familiar with the incidence of anatomical variations in the origin of the DMTAs can increase vigilance in vascular and reconstructive surgeries leading to better prognosis. surgeries leading to better prognosis.

  4. Increased sclerostin associated with stress fracture of the third metacarpal bone in the Thoroughbred racehorse

    Science.gov (United States)

    Singer, E.; Henson, F.

    2018-01-01

    Objectives The exact aetiology and pathogenesis of microdamage-induced long bone fractures remain unknown. These fractures are likely to be the result of inadequate bone remodelling in response to damage. This study aims to identify an association of osteocyte apoptosis, the presence of osteocytic osteolysis, and any alterations in sclerostin expression with a fracture of the third metacarpal (Mc-III) bone of Thoroughbred racehorses. Methods A total of 30 Mc-III bones were obtained; ten bones were fractured during racing, ten were from the contralateral limb, and ten were from control horses. Each Mc-III bone was divided into a fracture site, condyle, condylar groove, and sagittal ridge. Microcracks and diffuse microdamage were quantified. Apoptotic osteocytes were measured using TUNEL staining. Cathepsin K, matrix metalloproteinase-13 (MMP-13), HtrA1, and sclerostin expression were analyzed. Results In the fracture group, microdamage was elevated 38.9% (sd 2.6) compared with controls. There was no difference in the osteocyte number and the percentage of apoptotic cells between contralateral limb and unraced control; however, there were significantly fewer apoptotic cells in fractured samples (p fractured samples, sclerostin expression was significantly higher (p fractured during racing. In this study, this is not associated with osteocyte apoptosis or osteocytic osteolysis. The finding of increased sclerostin in the region of the fracture suggests that this protein may be playing a key role in the regulation of bone microdamage during stress adaptation. Cite this article: N. Hopper, E. Singer, F. Henson. Increased sclerostin associated with stress fracture of the third metacarpal bone in the Thoroughbred racehorse. Bone Joint Res 2018;7:94–102. DOI: 10.1302/2046-3758.71.BJR-2016-0202.R4. PMID:29363519

  5. Effect of Crack Tip Stress Concentration Factor on Fracture Resistance in Vacuum Environment

    Science.gov (United States)

    2015-01-20

    indicate: (1) in all alloys, the fracture resistance is highest for blunt-notches (smaller Kt), and is lowest for fatigue -sharpened precracked...paths are transgranular and the fracture mode is ductile void coalescence in all cases, irrespective of the stress concentration factor. 20-01-2015...because of corrosion and/or various loading conditions such as fatigue , fretting, abrasion, etc. Also, the geometry of the structure may cause an

  6. Method for stress determination in N, E, and T tunnels, Nevada Test Site, by hydraulic fracturing, with a comparison of overcoring methods

    International Nuclear Information System (INIS)

    Miller, C.H.

    1976-01-01

    Twenty-nine intervals in 10 core holes were hydraulically fractured in N, E, and T tunnels, Nevada Test Site, during 1974. Certain pressures were determined and related to the ambient stress field, but the orientation of the hydraulic fractures was not measured. These data and data from previous investigations in G tunnel indicated that both the magnitude of the hydraulic pressures and the direction of fracturing are independent of the orientation of the core holes. The maximum and minimum principal compressive stresses determined by the hydraulic fracturing methods are good approximations of those determined by nearby overcore methods. The data show that a good approximation of the magnitudes of the maximum and minimum principal stress axes can be obtained from several hydrofractured intervals in one core hole. Furthermore, if fracture orientation can be measured, then the direction of minimum principal compressive stress can be determined and the orientation of the plane of the maximum and intermediate principal compressive stresses can also be determined

  7. Effects of fluid dynamic stress on fracturing of cell-aggregated tissue during purification for islets of Langerhans transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Shintaku, H; Kawano, S [Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan); Okitsu, T [Transplantation Unit, Kyoto University Hospital, Kawara-cho Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Matsumoto, S [Baylor Research Institute Islet Cell Laboratory, 1400 Eight Avenue, Fort Worth, TX 76104 (United States); Suzuki, T; Kanno, I; Kotera, H [Department of Microengineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)], E-mail: shintaku@me.es.osaka-u.ac.jp

    2008-06-07

    Among clinical treatments for type 1 diabetes mellitus, the transplantation of islets of Langerhans to the portal vein of the hepar is a commonly used treatment for glucose homeostasis. Islet purification using the density gradient of a solution in a centrifuge separator is required for safety and efficiency. In the purification, the number of tissues to be transplanted is reduced by removing the acinar tissue and gathering the islet from the digest of pancreas. However, the mechanical effects on the fracture of islets in the centrifuge due to fluid dynamic stress are a serious problem in the purification process. In this study, a preliminary experiment using a cylindrical rotating viscometer with a simple geometry is conducted in order to systematically clarify the effect of fluid dynamic stress on the fracture of islets. The effects of fluid dynamic stress on the islet configuration is quantitatively measured for various flow conditions, and a predictive fracture model is developed based on the experimental results. Furthermore, in the practical purification process in the COBE (Gambro BCT), which is widely used in clinical applications, we perform a numerical analysis of the fluid dynamic stress based on Navier-Stokes equations to estimate the stress conditions for islets. Using the fracture model and numerical analysis, the islet fracture characteristics using the COBE are successfully investigated. The results obtained in this study provide crucial information for the purification of islets by centrifuge in practical and clinical applications.

  8. Effects of fluid dynamic stress on fracturing of cell-aggregated tissue during purification for islets of Langerhans transplantation

    International Nuclear Information System (INIS)

    Shintaku, H; Kawano, S; Okitsu, T; Matsumoto, S; Suzuki, T; Kanno, I; Kotera, H

    2008-01-01

    Among clinical treatments for type 1 diabetes mellitus, the transplantation of islets of Langerhans to the portal vein of the hepar is a commonly used treatment for glucose homeostasis. Islet purification using the density gradient of a solution in a centrifuge separator is required for safety and efficiency. In the purification, the number of tissues to be transplanted is reduced by removing the acinar tissue and gathering the islet from the digest of pancreas. However, the mechanical effects on the fracture of islets in the centrifuge due to fluid dynamic stress are a serious problem in the purification process. In this study, a preliminary experiment using a cylindrical rotating viscometer with a simple geometry is conducted in order to systematically clarify the effect of fluid dynamic stress on the fracture of islets. The effects of fluid dynamic stress on the islet configuration is quantitatively measured for various flow conditions, and a predictive fracture model is developed based on the experimental results. Furthermore, in the practical purification process in the COBE (Gambro BCT), which is widely used in clinical applications, we perform a numerical analysis of the fluid dynamic stress based on Navier-Stokes equations to estimate the stress conditions for islets. Using the fracture model and numerical analysis, the islet fracture characteristics using the COBE are successfully investigated. The results obtained in this study provide crucial information for the purification of islets by centrifuge in practical and clinical applications

  9. Cyclic Strain Resistance, Stress Response, Fatigue Life, and Fracture Behavior of High Strength Low Alloy Steel 300 M

    Science.gov (United States)

    Manigandan, K.; Srivatsan, T. S.; Tammana, Deepthi; Poorgangi, Behrang; Vasudevan, Vijay K.

    2014-05-01

    The focus of this technical manuscript is a record of the specific role of microstructure and test specimen orientation on cyclic stress response, cyclic strain resistance, and cyclic stress versus strain response, deformation and fracture behavior of alloy steel 300 M. The cyclic strain amplitude-controlled fatigue properties of this ultra-high strength alloy steel revealed a linear trend for the variation of log elastic strain amplitude with log reversals-to-failure, and log plastic strain amplitude with log reversals-to-failure for both longitudinal and transverse orientations. Test specimens of the longitudinal orientation showed only a marginal improvement over the transverse orientation at equivalent values of plastic strain amplitude. Cyclic stress response revealed a combination of initial hardening for the first few cycles followed by gradual softening for a large portion of fatigue life before culminating in rapid softening prior to catastrophic failure by fracture. Fracture characteristics of test specimens of this alloy steel were different at both the macroscopic and fine microscopic levels over the entire range of cyclic strain amplitudes examined. Both macroscopic and fine microscopic observations revealed fracture to be a combination of both brittle and ductile mechanisms. The underlying mechanisms governing stress response, deformation characteristics, fatigue life, and final fracture behavior are presented and discussed in light of the competing and mutually interactive influences of test specimen orientation, intrinsic microstructural effects, deformation characteristics of the microstructural constituents, cyclic strain amplitude, and response stress.

  10. Influence of shear and deviatoric stress on the evolution of permeability in fractured rock

    NARCIS (Netherlands)

    Faoro, Igor; Niemeijer, André; Marone, Chris; Elsworth, Derek

    The evolution of permeability in fractured rock as a function of effective normal stress, shear displacement, and damage remains a complex issue. In this contribution, we report on experiments in which rock surfaces were subject to direct shear under controlled pore pressure and true triaxial stress

  11. Fatigue-type stress fractures of the lower limb associated with fibrous cortical defects/non-ossifying fibromas in the skeletally immature.

    Science.gov (United States)

    Shimal, A; Davies, A M; James, S L J; Grimer, R J

    2010-05-01

    To investigate the association of a fatigue-type stress fracture and a fibrous cortical defect/non-ossifying fibroma (FCD/NOF) of the lower limb long bones in skeletally immature patients. The patient database of a specialist orthopaedic oncology centre was searched to determine the number of skeletally immature patients (lower limb long bone lesion ultimately shown to be a fatigue-type stress fracture. The diagnosis was established by a combination of typical imaging findings of a fatigue-type stress fracture, the absence of aggressive features suggestive of a sarcoma (e.g., interrupted periosteal reaction, cortical breach, and a soft-tissue mass) together with evidence of consolidation or healing on follow-up radiographs and resolution of symptoms over the subsequent weeks. The database was also used to determine the number of skeletally immature cases (lower limb long bones. The clinical and imaging features of those cases common to both groups (i.e., with both a fatigue-type stress fracture and a FCD or NOF) were reviewed. Six percent of patients (five cases) referred to an orthopaedic oncology unit, who were subsequently shown to have a stress fracture of the lower limb long bones, were found to have a related FCD/NOF. All had been referred with a suggested diagnosis of a bone sarcoma and/or osteomyelitis. The possibility of a stress fracture had been raised in only one case. Four cases involved the proximal tibia and one the distal femur. Radiographs revealed that both lesions arose in the posteromedial cortex in all but one of the cases. The radiographs and magnetic resonance imaging (MRI) features were considered typical of the overlapping pathological features of the lesions. A sarcoma could be effectively excluded in the absence of true cortical destruction and soft-tissue extension. Both fatigue-type stress fractures and FCD/NOFs occur at similar sites in the long bones. It is postulated that the existence of the latter may cause localized weakening of

  12. A retrospective cohort study on the influence of UV index and race/ethnicity on risk of stress and lower limb fractures.

    Science.gov (United States)

    Montain, Scott J; McGraw, Susan M; Ely, Matthew R; Grier, Tyson L; Knapik, Joseph J

    2013-04-12

    Low vitamin D status increases the risk of stress fractures. As ultraviolet (UV) light is required for vitamin D synthesis, low UV light availability is thought to increase the risk of vitamin D insufficiency and poor bone health. The purpose of this investigation was to determine if individuals with low UV intensity at their home of record (HOR) or those with darker complexions are at increased risk of developing stress fractures and lower limb fractures during U.S. Army Basic Combat Training (BCT). This was a retrospective cohort study using the Armed Forces Health Surveillance Center data repository. All Basic trainees were identified from January 1997 to January 2007. Cases were recruits diagnosed with stress fractures and lower limb fractures during BCT. The recruit's home of record (HOR) was identified from the Defense Manpower Data Center database. The average annual UV intensity at the recruits' HOR was determined using a U.S National Weather Service database and recruits were stratified into low (≤3.9); moderate (4.0-5.4), and high (≥5.5) UV index regions. Race was determined from self-reports. The dataset had 421,461 men and 90,141 women. Compared to men, women had greater risk of developing stress fractures (odds ratio (OR) = 4.5, 95% confidence interval (95%CI) = 4.4-4.7, p lower risk of stress fractures (male OR (low UV/high UV) = 0.92, 95%CI = 0.87-0.97; females OR = 0.89, 95%CI = 0.84-0.95, p lower limb fractures (male OR = 0.98, 95%CI = 0.89-1.07; female OR = 0.93, 95%CI = 0.80-1.09) than recruits from high UV index areas. Blacks had lower risk of stress and lower limb fractures than non-blacks, and there was no indication that Blacks from low UV areas were at increased risk for bone injuries. The UV index at home of record is not associated with stress or lower limb fractures in BCT. These data suggest that UV intensity is not a risk factor for poor bone health in younger American adults.

  13. Discrete fracture in quasi-brittle materials under compressive and tensile stress states

    CSIR Research Space (South Africa)

    Klerck, PA

    2004-01-01

    Full Text Available A method for modelling discrete fracture in geomaterials under tensile and compressive stress fields has been developed based on a Mohr-Coulomb failure surface in compression and three independent anisotropic rotating crack models in tension...

  14. Association of stressful life events with accelerated bone loss in older men: the Osteoporotic Fractures in Men (MrOS) Study

    Science.gov (United States)

    Fink, Howard A.; Kuskowski, Michael A.; Cauley, Jane A.; Taylor, Brent C.; Schousboe, John T.; Cawthon, Peggy M.; Ensrud, Kristine E.

    2015-01-01

    Purpose/Introduction Prior studies suggest that stressful life events may increase adverse health outcomes, including falls and possibly fractures. The current study builds on these findings and examines whether stressful life events are associated with increased bone loss. Methods 4388 men aged ≥65 years in the Osteoporotic Fractures in Men study completed total hip bone mineral density (BMD) measures at baseline and visit 2, approximately 4.6 years later, and self-reported stressful life events data mid-way between baseline and visit 2, and at visit 2. We used linear regression to model the association of stressful life events with concurrent annualized total hip BMD loss, and log binomial regression or Poisson regression to model risk of concurrent accelerated BMD loss (>1 SD more than mean annualized change). Results 75.3% of men reported ≥1 type of stressful life event, including 43.3% with ≥2 types of stressful life events. Mean annualized BMD loss was −0.36% (SD 0.88) and 13.9% of men were categorized with accelerated BMD loss (about 5.7% or more total loss). Rate of annualized BMD loss increased with the number of types of stressful life events after adjustment for age (pstressful life events (RR, 1.10 [95% CI, 1.04–1.16]) per increase of 1 type of stressful life event). Fracture risk was not significantly different between stressful life event-accelerated bone loss subgroups (p=0.08). Conclusions In these older men, stressful life events were associated with a small, dose-related increase in risk of concurrent accelerated hip bone loss. Low frequency of fractures limited assessment of whether rapid bone loss mediates any association of stressful life events with incident fractures. Future studies are needed to confirm these findings and to investigate the mechanism that may underlie this association. PMID:25169421

  15. Results of screw fixation combined with cortical drilling for treatment of dorsal cortical stress fractures of the third metacarpal bone in 56 Thoroughbred racehorses

    International Nuclear Information System (INIS)

    Dallap, B.L.; Bramlage, L.R.; Embertson, R.M.

    1999-01-01

    The purpose of this study was to evaluate screw fixation with cortical drilling as a surgical treatment for dorsal cortical stress fractures of MCIII in the Thoroughbred racehorse. Details of age, sex, limb affected, fracture assessment, and post operative recommendations were obtained from medical records and radiographs. Fracture healing was assessed radiographically at the time of screw removal. Performance evaluation was determined from race records obtained from The Jockey Club Information System, Lexington, Kentucky. Fifty-six Thoroughbred racehorses were treated surgically for stress fracture of MCIII with screw fixation and cortical drilling. Stress fractures occurred primarily in the left front limb of the male 3-year-olds, in the dorsolateral cortex of the middle third of MCIII. Ninety-seven percent of the fractures travelled in a dorsodistal to palmaroproximal direction. Median period to screw removal was 2.0 months. Evaluation at time of screw removal revealed 98% of single stress fractures of the left front limb were healed radiographically. Median period to resume training was 2.75 months (single stress fractures); median period to race was 7.62 months. There was no statistically significant difference in earnings/start before and after surgical intervention. Of the 63 fractures treated, two recurred. There were no catastrophic failures, and no incisional infections

  16. Residual stress effects on the K parameter of the fracture mechanics

    International Nuclear Information System (INIS)

    Soares, Maria da Conceiccao B. Vieira; Andrade, Arnaldo H. Paes de

    1996-01-01

    Compressive residual stresses are beneficial and improve resistance to fracture and crack growth. Residual stresses can be introduced in fabricated components by a variety of means and a number of methods such as laser surface treatment, cold expanded hole, and shot peening. Neutrons diffraction measurements of residual stress were performed at a pulsed neutron source (ISIS, Didcot, UK), on shot peened plates of nickel base superalloy Udimet 720 and titanium alloy IMI 834. The stress intensity factor (K) of residual stress was evaluated by finite element modeling and weight function method. Finite element modeling of a 2D plate with a single edge-notch was applied and, due to symmetry only half of the plate was actually modeled. The stress intensity factor (K) was evaluated for both case of remote tension stress and residual stress. Crack surface overlapping, which is physically unacceptable, was noted for small cracks under residual and boundary lading. Overlap correction was proposed and applied in order to obtain reliable values for (K). (author)

  17. [Effect of axial stress stimulation on tibial and fibular open fractures healing after Taylor space stent fixation].

    Science.gov (United States)

    Ge, Qihang; Wan, Chunyou; Liu, Yabei; Ji, Xu; Ma, Jihai; Cao, Haikun; Yong, Wei; Liu, Zhao; Zhang, Ningning

    2017-08-01

    To investigate the effect of axial stress stimulation on tibial and fibular open fractures healing after Taylor space stent fixation. The data of 45 cases with tibial and fibular open fractures treated by Taylor space stent fixation who meet the selection criteria between January 2015 and June 2016 were retrospectively analysed. The patients were divided into trial group (23 cases) and control group (22 cases) according to whether the axial stress stimulation was performed after operation. There was no significant difference in gender, age, affected side, cause of injury, type of fracture, and interval time from injury to operation between 2 groups ( P >0.05). The axial stress stimulation was performed in trial group after operation. The axial load sharing ratio was tested, and when the value was less than 10%, the external fixator was removed. The fracture healing time, full weight-bearing time, and external fixator removal time were recorded and compared. After 6 months of external fixator removal, the function of the limb was assessed by Johner-Wruhs criteria for evaluation of final effectiveness of treatment of tibial shaft fractures. There were 2 and 3 cases of needle foreign body reaction in trial group and control group, respectively, and healed after symptomatic anti allergic treatment. All the patients were followed up 8-12 months with an average of 10 months. All the fractures reached clinical healing, no complication such as delayed union, nonunion, or osteomyelitis occurred. The fracture healing time, full weight-bearing time, and external fixator removal time in trial group were significantly shorter than those in control group ( P good in 6 cases, fair in 3 cases, and poor in 1 case in trial group, with an excellent and good rate of 82.6%; and was excellent in 5 cases, good in 10 cases, fair in 4 cases, and poor in 3 cases in control group, with an excellent and good rate of 68.2%, showing significant difference between 2 groups ( Z =-2.146, P =0

  18. Model of T-Type Fracture in Coal Fracturing and Analysis of Influence Factors of Fracture Morphology

    Directory of Open Access Journals (Sweden)

    Yuwei Li

    2018-05-01

    Full Text Available Special T-type fractures can be formed when coal is hydraulically fractured and there is currently no relevant theoretical model to calculate and describe them. This paper first establishes the height calculation model of vertical fractures in multi-layered formations and deduces the stress intensity factor (SIF at the upper and lower sides of the fracture in the process of vertical fracture extension. Combined with the fracture tip stress analysis method of fracture mechanics theory, the horizontal bedding is taken into account for tensile and shear failure, and the critical mechanical conditions for the formation of horizontal fracture in coal are obtained. Finally, the model of T-type fracture in coal fracturing is established, and it is verified by fracturing simulation experiments. The model calculation result shows that the increase of vertical fracture height facilitates the increase of horizontal fracture length. The fracture toughness of coal has a significant influence on the length of horizontal fracture and there is a threshold. When the fracture toughness is less than the threshold, the length of horizontal fracture remains unchanged, otherwise, the length of horizontal fracture increases rapidly with the increase of fracture toughness. When the shear strength of the interface between the coalbed and the interlayer increases, the length of the horizontal fracture of the T-type fracture rapidly decreases.

  19. Section modulus is the optimum geometric predictor for stress fractures and medial tibial stress syndrome in both male and female athletes.

    Science.gov (United States)

    Franklyn, Melanie; Oakes, Barry; Field, Bruce; Wells, Peter; Morgan, David

    2008-06-01

    Various tibial dimensions and geometric parameters have been linked to stress fractures in athletes and military recruits, but many mechanical parameters have still not been investigated. Sedentary people, athletes with medial tibial stress syndrome, and athletes with stress fractures have smaller tibial geometric dimensions and parameters than do uninjured athletes. Cohort study; Level of evidence, 3. Using a total of 88 subjects, male and female patients with either a tibial stress fracture or medial tibial stress syndrome were compared with both uninjured aerobically active controls and uninjured sedentary controls. Tibial scout radiographs and cross-sectional computed tomography images of all subjects were scanned at the junction of the midthird and distal third of the tibia. Tibial dimensions were measured directly from the films; other parameters were calculated numerically. Uninjured exercising men have a greater tibial cortical cross-sectional area than do their sedentary and injured counterparts, resulting in a greater value of some other cross-sectional geometric parameters, particularly the section modulus. However, for women, the cross-sectional areas are either not different or only marginally different, and there are few tibial dimensions or geometric parameters that distinguish the uninjured exercisers from the sedentary and injured subjects. In women, the main difference between the groups was the distribution of cortical bone about the centroid as a result of the different values of section modulus. Last, medial tibial stress syndrome subjects had smaller tibial cross-sectional dimensions than did their uninjured exercising counterparts, suggesting that medial tibial stress syndrome is not just a soft-tissue injury but also a bony injury. The results show that in men, the cross-sectional area and the section modulus are the key parameters in the tibia to distinguish exercise and injury status, whereas for women, it is the section modulus only.

  20. Cleavage and creep fracture of rock salt

    International Nuclear Information System (INIS)

    Chan, K.S.; Munson, D.E.; Bodner, S.R.

    1996-01-01

    The dominant failure mechanism in rock salt at ambient temperature is either cleavage or creep fracture. Since the transition of creep fracture to cleavage in a compressive stress field is not well understood, failure of rock salt by cleavage and creep fracture is analyzed in this paper to elucidate the effect of stress state on the competition between these two fracture mechanisms. For cleavage fracture, a shear crack is assumed to cause the formation and growth of a symmetric pair of wing cracks in a predominantly compressive stress field. The conditions for wing-crack instability are derived and presented as the cleavage fracture boundary in the fracture mechanism map. Using an existing creep fracture model, stress conditions for the onset of creep fracture and isochronous failure curves of specified times-to-rupture are calculated and incorporated into the fracture mechanism map. The regimes of dominance by cleavage and creep fracture are established and compared with experimental data. The result indicates that unstable propagation of cleavage cracks occurs only in the presence of tensile stress. The onset of creep fracture is promoted by a tensile stress, but can be totally suppressed by a high confining pressure. Transition of creep fracture to cleavage occurs when critical conditions of stress difference and tensile stress for crack instability are exceeded

  1. Microstructural sensitivity of 316H austenitic stainless steel: Residual stress relaxation and grain boundary fracture

    Energy Technology Data Exchange (ETDEWEB)

    Chen, B., E-mail: b.chen@bristol.ac.uk [Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR (United Kingdom); Flewitt, P.E.J. [Interface Analysis Centre, University of Bristol, 121 St Michael' s Hill, Bristol BS2 8BS (United Kingdom); H.H. Wills Physics Laboratory, School of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Smith, D.J. [Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR (United Kingdom)

    2010-10-25

    Research highlights: {yields} Triaxial residual macro-stresses have been measured by neutron diffraction. {yields} Rates of stress relaxation are shown to be a function of the microstructure. {yields} Quantification of M{sub 23}C{sub 6} precipitation was undertaken by a novel approach. {yields} Intergranular M{sub 23}C{sub 6} precipitation promotes the potential to intergranular fracture. {yields} Phosphorous segregation further enhances the potential to intergranular fracture. - Abstract: The present work considers the role of thermo-mechanical history on the generation and relaxation of residual stresses, typical of those encountered in Type 316H austenitic stainless steel thick section weldments. A series of thermo-mechanical pre-treatments have been developed and applied to simulate the critical microstructures observed within the heat affected zone of the thick section parent material. The through thickness distributions of the residual macro-stresses in cylindrical specimens have been measured by neutron diffraction and then the rates of the relaxation are shown to be a function of microstructure. The susceptibility to intergranular brittle fracture at a temperature of -196 deg. C is shown to be a function of M{sub 23}C{sub 6} carbide precipitates and phosphorous segregation at the grain boundaries. Finally, the link of the present study to the understanding of the reheat cracking is briefly discussed.

  2. Sternal stress fracture in a gymnast: A case report and literature review

    African Journals Online (AJOL)

    There is a high incidence of injuries among gymnasts.1 This is not surprising given the ... stress fracture. A common example of poor posture in gymnasts is excessive ... Dimakatso Althea Ramagole (MB ChB, MSc (Sports Med)). Dina Christina ...

  3. Consistent stress-strain ductile fracture model as applied to two grades of beryllium

    International Nuclear Information System (INIS)

    Priddy, T.G.; Benzley, S.E.; Ford, L.M.

    1980-01-01

    Published yield and ultimate biaxial stress and strain data for two grades of beryllium are correlated with a more complete method of characterizing macroscopic strain at fracture initiation in ductile materials. Results are compared with those obtained from an exponential, mean stress dependent, model. Simple statistical methods are employed to illustrate the degree of correlation for each method with the experimental data

  4. Double Threaded Screw Fixation for Bilateral Stress Fracture of the Medial Malleolus

    Directory of Open Access Journals (Sweden)

    Ryo Kanto

    2014-01-01

    Full Text Available An 18-year-old college basketball player presented with continued ankle pain. A radiographic examination showed bilateral medial malleolus stress fractures. Considering the prolonged history and refractory nature of this injury, surgery was adopted as a treatment option. At surgery, the fracture site was percutaneously fixed using two cannulated double threaded screws. Surgery for each side was sequentially performed two months apart. Prompt bony healing was attained after surgery, and the patient could return to his previous sports level six months after the first surgery without subsequent recurrence.

  5. Dependence of fracture mechanical and fluid flow properties on fracture roughness and sample size

    International Nuclear Information System (INIS)

    Tsang, Y.W.; Witherspoon, P.A.

    1983-01-01

    A parameter study has been carried out to investigate the interdependence of mechanical and fluid flow properties of fractures with fracture roughness and sample size. A rough fracture can be defined mathematically in terms of its aperture density distribution. Correlations were found between the shapes of the aperture density distribution function and the specific fractures of the stress-strain behavior and fluid flow characteristics. Well-matched fractures had peaked aperture distributions that resulted in very nonlinear stress-strain behavior. With an increasing degree of mismatching between the top and bottom of a fracture, the aperture density distribution broadened and the nonlinearity of the stress-strain behavior became less accentuated. The different aperture density distributions also gave rise to qualitatively different fluid flow behavior. Findings from this investigation make it possible to estimate the stress-strain and fluid flow behavior when the roughness characteristics of the fracture are known and, conversely, to estimate the fracture roughness from an examination of the hydraulic and mechanical data. Results from this study showed that both the mechanical and hydraulic properties of the fracture are controlled by the large-scale roughness of the joint surface. This suggests that when the stress-flow behavior of a fracture is being investigated, the size of the rock sample should be larger than the typical wave length of the roughness undulations

  6. Revisiting fracture gradient: Comments on “A new approaching method to estimate fracture gradient by correcting Matthew–Kelly and Eaton's stress ratio”

    KAUST Repository

    Hakiki, Farizal

    2017-07-25

    A study performed by Marbun et al. [1] claimed that “A new methodology to predict fracture pressure from former calculations, Matthew–Kelly and Eaton are proposed.” Also, Marbun et al.\\'s paper stated that “A new value of Poisson\\'s and a stress ratio of the formation were generated and the accuracy of fracture gradient was improved.” We found those all statements are incorrect and some misleading concepts are revealed. An attempt to expose the method of fracture gradient determination from industry practice also appears to solidify that our arguments are acceptable to against improper Marbun et al.\\'s claims.

  7. Effect of plastic strain on elastic-plastic fracture toughness of SM490 carbon steel. Assessment by stress-based criterion for ductile crack initiation

    International Nuclear Information System (INIS)

    Kamaya, Masayuki

    2012-01-01

    Although the plastic strain induced in materials increases the mechanical strength, it may reduce the fracture toughness. In this study, the change in fracture toughness of SM490 carbon steel due to pre-straining was investigated using a stress-based criterion for ductile crack initiation. The specimens with blunt notch of various radiuses were used in addition to those with conventional fatigue pre-cracking. The degree of applied plastic strain was 5%, 10% or 20%. The fracture toughness was largest when the induced plastic strain was 5%, although it decreased for the plastic strains of 10% and 20%. The stress and strain distributions near the crack tip of fracture toughness test specimens was investigated by elastic-plastic finite element analyses using a well-correlated stress-strain curve for large strain. It was shown that the critical condition at the onset of the ductile crack was better correlated with the equivalent stress than the plastic strain at the crack tip. By using the stress-based criterion, which was represented by the equivalent stress and stress triaxiality, the change in the fracture toughness due to pre-straining could be reasonably explained. Based on these results, it was concluded that the stress-based criterion should be used for predicting the ductile crack initiation. (author)

  8. Intrapartum sacral stress fracture due to pregnancy-related osteoporosis: a case report.

    Science.gov (United States)

    Oztürk, Gülcan; Külcü, Duygu Geler; Aydoğ, Ece

    2013-01-01

    Low back pain (LBP) and hip pain frequently occur during pregnancy and postpartum period. Although pelvic and mechanic lesions of the soft tissues are most responsible for the etiology, sacral fracture is also one of the rare causes. A 32-year-old primigravid patient presented with LBP and right hip pain which started 3 days after vaginal delivery. Although direct radiographic examination was normal, magnetic resonance imaging of the sacrum revealed sacral stress fracture. Lumbar spine and femoral bone mineral density showed osteoporosis as a risk factor. There were no other risk factors such as trauma, excessive weight gain, and strenuous physical activity. It is considered that the patient had sacral fatigue and insufficiency fracture in intrapartum period. The patient's symptoms subsided in 3 months after physical therapy and rest. In conclusion, sacral fractures during pregnancy and postpartum period, especially resulting from childbirth, are very rare. To date, there are two cases in the literature. In cases who even do not have risk factors related to vaginal delivery such as high birth weight infant and the use of forceps, exc., sacral fracture should be considered in the differential diagnosis of LBP and hip pain started soon after child birth. Pregnancy-related osteoporosis may lead to fracture during vaginal delivery.

  9. Negative magnetic resonance imaging in three cases of anterior tibial cortex stress fractures

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Ralph; Moghal, M.; Newton, J.L.; Jones, N. [Oxford University Hospitals NHS Foundation Trust, Department of Sport and Exercise Medicine, Nuffield Orthopaedic Centre, Oxford (United Kingdom); Teh, J. [Oxford University Hospitals NHS Foundation Trust, Department of Radiology, Nuffield Orthopaedic Centre Oxford, Oxford (United Kingdom)

    2017-12-15

    Anterior mid-tibial cortex stress fractures (ATCSF) are uncommon and notoriously challenging to treat. They are termed high risk due to their predilection to prolonged recovery, nonunion and complete fracture. Early diagnosis is essential to avoid progression and reduce fracture complications. Imaging plays a key role in confirming the diagnosis. Magnetic resonance imaging (MRI) is accepted as the gold standard modality due to its high accuracy and nonionizing properties. This report describes three cases of ATCSFs in recreational athletes who had positive radiographic findings with no significant MRI changes. Two athletes had multiple striations within their tibias. Despite the radiographic findings, their severity of symptoms were low with mild or no tenderness on examination. Clinicians should be mindful that the ATCSFs may not present with typical acute stress fracture symptoms. We recommend that plain radiographs should be used as the first line investigation when suspecting ATCSFs. Clinicians should be aware that despite MRI being considered the gold standard imaging modality, we report three cases where the MRI was unremarkable, whilst radiographs and computed tomography confirmed the diagnosis. We urge clinicians to continue to use radiographs as the first line imaging modality for ATCSFs and not to directly rely on MRI. Those who opt directly for MRI may be falsely reassured causing a delay in diagnosis. (orig.)

  10. Negative magnetic resonance imaging in three cases of anterior tibial cortex stress fractures

    International Nuclear Information System (INIS)

    Smith, Ralph; Moghal, M.; Newton, J.L.; Jones, N.; Teh, J.

    2017-01-01

    Anterior mid-tibial cortex stress fractures (ATCSF) are uncommon and notoriously challenging to treat. They are termed high risk due to their predilection to prolonged recovery, nonunion and complete fracture. Early diagnosis is essential to avoid progression and reduce fracture complications. Imaging plays a key role in confirming the diagnosis. Magnetic resonance imaging (MRI) is accepted as the gold standard modality due to its high accuracy and nonionizing properties. This report describes three cases of ATCSFs in recreational athletes who had positive radiographic findings with no significant MRI changes. Two athletes had multiple striations within their tibias. Despite the radiographic findings, their severity of symptoms were low with mild or no tenderness on examination. Clinicians should be mindful that the ATCSFs may not present with typical acute stress fracture symptoms. We recommend that plain radiographs should be used as the first line investigation when suspecting ATCSFs. Clinicians should be aware that despite MRI being considered the gold standard imaging modality, we report three cases where the MRI was unremarkable, whilst radiographs and computed tomography confirmed the diagnosis. We urge clinicians to continue to use radiographs as the first line imaging modality for ATCSFs and not to directly rely on MRI. Those who opt directly for MRI may be falsely reassured causing a delay in diagnosis. (orig.)

  11. The effect of multiaxial stress state on creep behavior and fracture mechanism of P92 steel

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yuan; Xu, Hong, E-mail: xuhong@ncepu.edu.cn; Ni, Yongzhong; Lan, Xiang; Li, Hongyuan

    2015-06-11

    The creep experiments on plain and double U-typed notched specimens were conducted on P92 steel at 650 °C. The notch strengthening effect was found in the notched specimens. Fracture appearance observed by scanning electron microscopy revealed that dimpled fracture for relatively blunt notched specimen, and dimpled fracture doubled with intergranular brittle fracture for relatively sharp notched specimen, which meant that fracture mechanism of P92 steel altered due to the presence of the notch. Meanwhile, based on Norton–Bailey and Kachanov–Robotnov constitutive models, a modified model was proposed. Finite element simulations were carried out to investigate the effect of multiaxial stress state on the creep behavior, fracture mechanism and damage evolvement of P92 steel. The simulation results agreed well with the fracture behaviors observed experimentally.

  12. Fatigue-type stress fractures of the lower limb associated with fibrous cortical defects/non-ossifying fibromas in the skeletally immature

    Energy Technology Data Exchange (ETDEWEB)

    Shimal, A.; Davies, A.M. [Department of Radiology, Royal Orthopaedic Hospital, Birmingham B31 2AP (United Kingdom); James, S.L.J., E-mail: steven.james@roh.nhs.u [Department of Radiology, Royal Orthopaedic Hospital, Birmingham B31 2AP (United Kingdom); Grimer, R.J. [Department of Orthopaedic Oncology, Royal Orthopaedic Hospital, Birmingham B31 2AP (United Kingdom)

    2010-05-15

    Aim: To investigate the association of a fatigue-type stress fracture and a fibrous cortical defect/non-ossifying fibroma (FCD/NOF) of the lower limb long bones in skeletally immature patients. Materials and methods: The patient database of a specialist orthopaedic oncology centre was searched to determine the number of skeletally immature patients (<=16 years of age) over an 18 year period with a lower limb long bone lesion ultimately shown to be a fatigue-type stress fracture. The diagnosis was established by a combination of typical imaging findings of a fatigue-type stress fracture, the absence of aggressive features suggestive of a sarcoma (e.g., interrupted periosteal reaction, cortical breach, and a soft-tissue mass) together with evidence of consolidation or healing on follow-up radiographs and resolution of symptoms over the subsequent weeks. The database was also used to determine the number of skeletally immature cases (<=16 years of age) referred in the same period in which the principal lesion was shown to be a fibrous cortical defect (FCD) or non-ossifying fibroma (NOF) of the lower limb long bones. The clinical and imaging features of those cases common to both groups (i.e., with both a fatigue-type stress fracture and a FCD or NOF) were reviewed. Results: Six percent of patients (five cases) referred to an orthopaedic oncology unit, who were subsequently shown to have a stress fracture of the lower limb long bones, were found to have a related FCD/NOF. All had been referred with a suggested diagnosis of a bone sarcoma and/or osteomyelitis. The possibility of a stress fracture had been raised in only one case. Four cases involved the proximal tibia and one the distal femur. Radiographs revealed that both lesions arose in the posteromedial cortex in all but one of the cases. The radiographs and magnetic resonance imaging (MRI) features were considered typical of the overlapping pathological features of the lesions. Conclusions: A sarcoma could be

  13. Fatigue-type stress fractures of the lower limb associated with fibrous cortical defects/non-ossifying fibromas in the skeletally immature

    International Nuclear Information System (INIS)

    Shimal, A.; Davies, A.M.; James, S.L.J.; Grimer, R.J.

    2010-01-01

    Aim: To investigate the association of a fatigue-type stress fracture and a fibrous cortical defect/non-ossifying fibroma (FCD/NOF) of the lower limb long bones in skeletally immature patients. Materials and methods: The patient database of a specialist orthopaedic oncology centre was searched to determine the number of skeletally immature patients (≤16 years of age) over an 18 year period with a lower limb long bone lesion ultimately shown to be a fatigue-type stress fracture. The diagnosis was established by a combination of typical imaging findings of a fatigue-type stress fracture, the absence of aggressive features suggestive of a sarcoma (e.g., interrupted periosteal reaction, cortical breach, and a soft-tissue mass) together with evidence of consolidation or healing on follow-up radiographs and resolution of symptoms over the subsequent weeks. The database was also used to determine the number of skeletally immature cases (≤16 years of age) referred in the same period in which the principal lesion was shown to be a fibrous cortical defect (FCD) or non-ossifying fibroma (NOF) of the lower limb long bones. The clinical and imaging features of those cases common to both groups (i.e., with both a fatigue-type stress fracture and a FCD or NOF) were reviewed. Results: Six percent of patients (five cases) referred to an orthopaedic oncology unit, who were subsequently shown to have a stress fracture of the lower limb long bones, were found to have a related FCD/NOF. All had been referred with a suggested diagnosis of a bone sarcoma and/or osteomyelitis. The possibility of a stress fracture had been raised in only one case. Four cases involved the proximal tibia and one the distal femur. Radiographs revealed that both lesions arose in the posteromedial cortex in all but one of the cases. The radiographs and magnetic resonance imaging (MRI) features were considered typical of the overlapping pathological features of the lesions. Conclusions: A sarcoma could be

  14. Anterior tension band plating for anterior tibial stress fractures in high-performance female athletes: a report of 4 cases

    NARCIS (Netherlands)

    Borens, Olivier; Sen, Milan K.; Huang, Russel C.; Richmond, Jeffrey; Kloen, Peter; Jupiter, Jesse B.; Helfet, David L.

    2006-01-01

    Stress fracture of the anterior tibial cortex is an extremely challenging fracture to treat, especially in the high-performance female athlete who requires rapid return to competition. Previous reports have not addressed treating these fractures in the world-class athlete with anterior plating. We

  15. A stress-based fracture criteria validated on mixed microstructures of ferrite and bainite over a range of stress triaxialities

    Energy Technology Data Exchange (ETDEWEB)

    Golling, Stefan, E-mail: stefan.golling@ltu.se [Luleå University of Technology, SE 971 87 Luleå (Sweden); Östlund, Rickad [Gestamp HardTech, Ektjärnsvägen 5, SE 973 45 Luleå (Sweden); Oldenburg, Mats [Luleå University of Technology, SE 971 87 Luleå (Sweden)

    2016-09-30

    Hot stamping is a sequential process for formation and heat-treatment of sheet metal components with superior mechanical properties. By applying different cooling rates, the microstructural composition and thus the material properties of steel can be designed. By controlling the cooling rate in different sections of a blank, the material properties can be tailored depending on the desired toughness. Under continuous cooling, various volume fractions of ferrite and bainite are formed depending on the rate of cooling. This paper focuses on the ductile fracture behavior of a thin sheet metal made of low-alloyed boron steel with varying amounts of ferrite and bainite. An experimental setup was applied in order to produce microstructures with different volume fractions of ferrite and bainite. In total, five different test specimen geometries, representing different stress triaxialities, were heat treated and tensile tested. Through full-field measurements, flow curves extending beyond necking and the equivalent plastic strain to fracture were determined. Experimental results were further investigated using a mean-field homogenization scheme combined with local fracture criteria. The mean-field homogenization scheme comprises the influence of microstructure composition and stress triaxiality with usable accuracy, connoting auspicious possibilities for constitutive modeling of hot-stamped components.

  16. Are Elite Female Soccer Athletes at Risk for Disordered Eating Attitudes, Menstrual Dysfunction, and Stress Fractures?

    Science.gov (United States)

    Prather, Heidi; Hunt, Devyani; McKeon, Kathryn; Simpson, Scott; Meyer, E Blair; Yemm, Ted; Brophy, Robert

    2016-03-01

    To determine the prevalence of stress fractures, menstrual dysfunction and disordered eating attitudes in elite female soccer athletes. Cross-sectional descriptive study. Female soccer athletes were recruited from a national level youth soccer club, an NCAA Division I university team, and a women's professional team. Two hundred twenty female soccer athletes with a mean age of 16.4 ± 4 years and BMI of 20.8 ± 2 kg/m(2) completed the study, representing all athletes from the included teams. One-time surveys completed by the athletes. Height and weight were recorded, and body mass index (BMI) was calculated for each athlete. Athletes reported age of menarche, history of missing 3 or more menses within a 12-month period and stress fracture. The Eating Attitudes Test (EAT-26) was used to assess the athlete's body perception and attitudes toward eating. Of the 220 soccer athletes, 3 athletes (1.6%) had a low BMI for their age, and 19 (8.6%) reported stress fractures of the lower extremity. Among athletes who had reached menarche, the average onset was 13 + 1 year; menstrual dysfunction were present in 21 (19.3%). On the EAT-26, 1 player scored in the high risk range (>20) and 17 (7.7%) scored in the intermediate risk range (10-19) for eating disorders. Athletes with an EAT-26 score ≥ 10 points had a significantly higher prevalence of menstrual dysfunction in the past year compared to athletes with an EAT-26 score of less than 10 (P = .02). Elite female soccer athletes are susceptible to stress fractures and menstrual dysfunction and have delayed onset of menarche despite normal BMI and appropriate body perception and attitudes towards eating. Further studies are needed to better understand stress fracture risk in female soccer athletes and in other team sports to determine how these findings relate to long-term bone health in this population. Copyright © 2016. Published by Elsevier Inc.

  17. Do Capacity Coupled Electric Fields Accelerate Tibial Stress Fracture Healing

    Science.gov (United States)

    2006-12-01

    MRI confirmed a large coexisting haemangioma which may have confounded perception of stress fracture symptoms. Table 1 is a comprehensive subject...Johnson JR, Light KI, Yuan HA: A double-blind study of capacitively coupled electrical stimulation as an adjunct to lumbar spinal fusions. Spine 24...Simmons JW, Jr., Mooney V, Thacker I: Pseudarthrosis after lumbar spine fusion: nonoperative salvage with pulsed electromagnetic fields. Am J

  18. Imaging of upper extremity stress fractures in the athlete.

    Science.gov (United States)

    Anderson, Mark W

    2006-07-01

    Although it is much less common than injuries in the lower extremities, an upper extremity stress injury can have a significant impact on an athlete. If an accurate and timely diagnosis is to be made, the clinician must have a high index of suspicion of a stress fracture in any athlete who is involved in a throwing, weightlifting, or upper extremity weight-bearing sport and presents with chronic pain in the upper extremity. Imaging should play an integral role in the work-up of these patients; if initial radiographs are unrevealing, further cross-sectional imaging should be strongly considered. Although a three-phase bone scan is highly sensitive in this regard, MRI has become the study of choice at most centers.

  19. Osteomalacia and coxa vara. An unusual co-existence for femoral neck stress fracture

    Directory of Open Access Journals (Sweden)

    Kerim Sariyilmaz

    2015-01-01

    Conclusion: Joint and bone pain without any trauma should be investigated and bone metabolism disorders should be kept in mind. There might be co-existing factors related with stress fractures, and they must be treated simultaneously.

  20. Ipsilateral stress fracture of the proximal fibula after total knee arthroplasty in a patient with severe valgus knee deformity on a background of Rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Hirokazu Takai

    Full Text Available Introduction: Previous studies have reported a lower extremity stress fracture after total knee arthroplasty (TKA. However, a fibular fracture after TKA is quite rare. We report a case of proximal fibula fracture after TKA in a patient with rheumatoid arthritis (RA. Presentation of case: A 45 year old woman with RA had severe knee and foot pain with an antalgic gait disturbance. There was a significant joint deformity in many of lower limb joints. Interval bilateral TKAs were performed two weeks apart. Right TKA was performed using a constraint-type prosthesis, through lateral parapatellar approach. Left TKA was performed using a posterior-stabilized (PS prosthesis through the more commonly employed, medial parapatellar approach. Seven weeks after the right TKA, the patient was found to have an atraumatic proximal fibular fracture. The fracture went on to heal conservatively. Discussion: The fracture was considered to have occurred after the TKA. The callus appeared eleven weeks after the TKA. The factors that contributed to the fracture were thought to be overload of the fragile bone secondarily to disuse osteopaenia, RA or potentially the significant valgus malalignment correction. The surgical approach, the implant or implantation or the persisting joint deformity, were thought to be contributing factors to the aetiology of the stress fracture. The resultant change in clinical outcome/course is outlined in this case report. Conclusion: A stress fracture of the proximal fibula has the potential in the aetiology of may cause other stress fractures, joint other instability, and/or malalignment of the total lower extremity. Keywords: Stress fracture, Insufficiency fracture, Total knee arthroplasty, Fibula fracture, Valgus deformity, Rheumatoid arthritis

  1. Effects of root radius, stress, crack growth and rate on fracture instability

    Energy Technology Data Exchange (ETDEWEB)

    McClintock, F A

    1965-01-01

    Of various criteria for fracture at the root of a notch, the energy, local stress, and displacement criteria have limited validity. More appropriate is the history of both stress and strain over a small region ahead of the crack, as required for fracture by the coalescence of holes. Expressions are given for crack initiation, growth, and subsequent instability in anti-plane strain of a nonhardening material. Instability is shown to depend primarily on those strain increments arising from crack growth at constant load rather than on those from increasing load at constant crack length. Thus final instability conditions are similar for single and double- ended cracks, round notches, and cracks cut under constant load. Round notches may give instability, restabilization and final instability. The growth and coalescence of holes in front of a crack in a linearly viscous material is studied for both tensile and anti-plant-strain cracks. The absence of residual strain eliminates instability, but the crack continually accelerates. (26 refs.)

  2. Adductor insertion avulsion syndrome with stress fracture of femoral shaft: MRI findings

    International Nuclear Information System (INIS)

    Lawande, M.A.; Sankhe, S.; Pungavkar, S.A.; Patkar, D.P.

    2007-01-01

    Full text: Chronic vague hip pain may be caused by stress-related injury in the proximal or mid-femoral diaphysis. This has been described as an entity called adductor insertion avulsion syndrome, or thigh splints. In the appropriate clinical setting, the radiologist interpreting the magnetic resonance imaging must be aware of this condition as its imaging findings are subtle. The diagnosis will help the clinician plan the appropriate management. Magnetic resonance imaging can also depict the complications such as stress fracture

  3. Application of hydraulic fracturing to determine virgin in situ stress state around Waste Isolation Pilot Plant - in situ measurements

    International Nuclear Information System (INIS)

    Wawersik, W.R.; Stone, C.M.

    1985-10-01

    Hydraulic fracturing tests were carried out in horizontal drillholes in rock salt in the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM. It was determined that the virgin in situ stress field is isotropic or nearly isotropic. The inferred magnitude of the isotropic in situ stress falls between bounds of 14.28 MPa and 17.9 MPa for the average breakdown/reopening pressures and driving pressures. The best estimate from instantaneous shut-in pressures is 16.61 MPa. Given some uncertainties about the interpretation of hydraulic fracturing data in salt, all of the foregoing values are in acceptable agreement with an average calculated isotropic in situ stress of 14.9 MPa at an average depth of 657 m below surface. Interpretations of breakdown and reopening pressures are based on finite element analyses of the relaxed stress field around a borehole in salt. This stress field varies little between approximately 50 and 200 days after drilling. The finite element analyses were also used to interpret the observed stable pressure-time signatures with little or no pressure drops during primary breakdown of the salt formation. The conclusion about the isotropic nature of the virgin in situ stress field is supported by observations of the induced fracture patterns. The report includes a comparison of the hydrofrac data in the WIPP with the published results of hydraulic fracturing tests in salt at three other locations. 75 refs., 21 figs., 4 tabs

  4. Expedited patient-specific assessment of contact stress exposure in the ankle joint following definitive articular fracture reduction.

    Science.gov (United States)

    Kern, Andrew M; Anderson, Donald D

    2015-09-18

    Acute injury severity, altered joint kinematics, and joint incongruity are three important mechanical factors linked to post-traumatic osteoarthritis (PTOA). Finite element analysis (FEA) was previously used to assess the influence of increased contact stress due to joint incongruity on PTOA development. While promising agreement with PTOA development was seen, the inherent complexities of contact FEA limited the numbers of subjects that could be analyzed. Discrete element analysis (DEA) is a simplified methodology for contact stress computation, which idealizes contact surfaces as a bed of independent linear springs. In this study, DEA was explored as an expedited alternative to FEA contact stress exposure computation. DEA was compared to FEA using results from a previously completed validation study of two cadaveric human ankles, as well as a previous study of post-operative contact stress exposure in 11 patients with tibial plafond fracture. DEA-computed maximum contact stresses were within 19% of those experimentally measured, with 90% of the contact area having computed contact stress values within 1MPa of those measured. In the 11 fractured ankles, maximum contact stress and contact area differences between DEA and FEA were 0.85 ± 0.64 MPa and 22.5 ± 11.5mm(2). As a predictive measure for PTOA development, both DEA and FEA had 100% concordance with presence of OA (KL grade ≥ 2) and >95% concordance with KL grade at 2 years. These results support DEA as a reasonable alternative to FEA for computing contact stress exposures following surgical reduction of a tibial plafond fracture. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. On size effects in fracture

    International Nuclear Information System (INIS)

    Sinclair, G.B.

    1985-01-01

    This paper discusses the dependence of fracture stress on size. This conclusion is based on classical energy arguments. For an in-plane scaled specimen pair, the larger the specimen the smaller the fracture stress. In contrast the same theory gives a different dependence for out-of-plane specimen and the dependence involves plane stress, strain, fracture stresses and Poisson's ratio. The objective of this paper is to examine how well these predictions are actually complied with

  6. Delayed Union of a Jones Fracture in a Patient With Rothmund-Thomson Syndrome: A Case Report and Review of the Literature.

    Science.gov (United States)

    Barisonek, Kirsten L; Protzman, Nicole M; Wobst, Garrett M; Brigido, Stephen A

    2016-01-01

    Rothmund-Thomson syndrome is a rare autosomal recessive genodermatosis, characterized by poikiloderma, small stature, juvenile cataracts, sparse hair, skeletal abnormalities, and a predisposition to osteogenic sarcomas and skin cancers. Although numerous skeletal abnormalities have been described in patients with Rothmund-Thomson syndrome, to our knowledge, only 1 study has shown evidence of delayed fracture healing in a patient with Rothmund-Thomson syndrome. We present the case of a 13-year-old female diagnosed with Rothmund-Thomson syndrome who demonstrated delayed union of her fifth metatarsal after a Jones fracture. She was treated conservatively for 6 weeks with non-weightbearing cast immobilization and was then transitioned to a controlled ankle motion walker for an additional 4 weeks. Two months later, however, she continued to experience pain, and, on radiographic examination, the fracture remained unchanged. Therefore, with her guardian's consent, the patient elected to undergo open reduction and internal fixation of the fifth metatarsal fracture. At 8 weeks postoperatively, the patient reported a subsidence of symptoms and had returned to normal activity. With our report, we hope to increase practitioner awareness that delayed bone healing could be a possibility in patients with Rothmund-Thomson syndrome and encourage consideration of routine imaging and supplementation with calcium and vitamin D. Additionally, the present findings suggest that patients with Rothmund-Thomson syndrome could benefit from early surgical intervention, given their poor bone healing capacity and high likelihood of nonunion. Although the association between impaired bone healing and Rothmund-Thomson syndrome is rational, additional studies are needed to determine the prevalence of chronic nonunion in this patient population. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  7. The concept of the average stress in the fracture process zone for the search of the crack path

    Directory of Open Access Journals (Sweden)

    Yu.G. Matvienko

    2015-10-01

    Full Text Available The concept of the average stress has been employed to propose the maximum average tangential stress (MATS criterion for predicting the direction of fracture angle. This criterion states that a crack grows when the maximum average tangential stress in the fracture process zone ahead of the crack tip reaches its critical value and the crack growth direction coincides with the direction of the maximum average tangential stress along a constant radius around the crack tip. The tangential stress is described by the singular and nonsingular (T-stress terms in the Williams series solution. To demonstrate the validity of the proposed MATS criterion, this criterion is directly applied to experiments reported in the literature for the mixed mode I/II crack growth behavior of Guiting limestone. The predicted directions of fracture angle are consistent with the experimental data. The concept of the average stress has been also employed to predict the surface crack path under rolling-sliding contact loading. The proposed model considers the size and orientation of the initial crack, normal and tangential loading due to rolling–sliding contact as well as the influence of fluid trapped inside the crack by a hydraulic pressure mechanism. The MATS criterion is directly applied to equivalent contact model for surface crack growth on a gear tooth flank.

  8. Discrete element analysis is a valid method for computing joint contact stress in the hip before and after acetabular fracture.

    Science.gov (United States)

    Townsend, Kevin C; Thomas-Aitken, Holly D; Rudert, M James; Kern, Andrew M; Willey, Michael C; Anderson, Donald D; Goetz, Jessica E

    2018-01-23

    Evaluation of abnormalities in joint contact stress that develop after inaccurate reduction of an acetabular fracture may provide a potential means for predicting the risk of developing post-traumatic osteoarthritis. Discrete element analysis (DEA) is a computational technique for calculating intra-articular contact stress distributions in a fraction of the time required to obtain the same information using the more commonly employed finite element analysis technique. The goal of this work was to validate the accuracy of DEA-computed contact stress against physical measurements of contact stress made in cadaveric hips using Tekscan sensors. Four static loading tests in a variety of poses from heel-strike to toe-off were performed in two different cadaveric hip specimens with the acetabulum intact and again with an intentionally malreduced posterior wall acetabular fracture. DEA-computed contact stress was compared on a point-by-point basis to stress measured from the physical experiments. There was good agreement between computed and measured contact stress over the entire contact area (correlation coefficients ranged from 0.88 to 0.99). DEA-computed peak contact stress was within an average of 0.5 MPa (range 0.2-0.8 MPa) of the Tekscan peak stress for intact hips, and within an average of 0.6 MPa (range 0-1.6 MPa) for fractured cases. DEA-computed contact areas were within an average of 33% of the Tekscan-measured areas (range: 1.4-60%). These results indicate that the DEA methodology is a valid method for accurately estimating contact stress in both intact and fractured hips. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. The effect of through-thickness compressive stress on mode II interlaminar fracture toughness

    NARCIS (Netherlands)

    Catalanotti, G.; Furtado, C.; Scalici, T.; Pitarresi, G.; van der Meer, F.P.; Camanho, PP

    2017-01-01

    The effect of through-thickness compressive stress on mode II interlaminar fracture toughness is investigated experimentally and replicated numerically. The modified Transverse Crack Tensile specimen recently proposed by the authors is used, together with an experimental device designed to apply

  10. Stress fractures of the hind limb in 2 Thoroughbreds

    International Nuclear Information System (INIS)

    Nelson, A.

    1994-01-01

    Stress factures are a common arthopaedic injury in human and equine athletes (McBryde 1985; Mackey et al. 1987). Although often presenting as acute lameness in the horse they are the accumulation of a long period of bone remodelling and eventual failure (Jones and Harris 1989). Gamma scintigraphy has been useful in the diagnosis of stress fractures in humans (Prather et al. 1977) and horses (Devous and Twardock 1984) and is more sensitive than radiography due to its ability to detect functional changes in bone metabolism (Matin 1988). Gamma scintigraphy may be performed in the horse using a hand held probe (Pilsworth 1989) or a gamma camera (Ueltshi 1977). The following cases were both investigated using a gamma camera and dedicated computer system (Elscint UK, Colonial Business Park, Watford, UK)

  11. Mechanics of Hydraulic Fractures

    Science.gov (United States)

    Detournay, Emmanuel

    2016-01-01

    Hydraulic fractures represent a particular class of tensile fractures that propagate in solid media under pre-existing compressive stresses as a result of internal pressurization by an injected viscous fluid. The main application of engineered hydraulic fractures is the stimulation of oil and gas wells to increase production. Several physical processes affect the propagation of these fractures, including the flow of viscous fluid, creation of solid surfaces, and leak-off of fracturing fluid. The interplay and the competition between these processes lead to multiple length scales and timescales in the system, which reveal the shifting influence of the far-field stress, viscous dissipation, fracture energy, and leak-off as the fracture propagates.

  12. Intergranular fracture stress and phosphorus grain boundary segregation of a Mn-Ni-Mo steel

    International Nuclear Information System (INIS)

    Naudin, C.; Frund, J.M.; Pineau, A.

    1999-01-01

    Nuclear Reactor Pressure Vessel (RPV) steel A508 class 3 which is a low alloyed steel is not usually sensitive to reversible temper embrittlement when properly heat treated. However heterogeneous zones may be present in particular near the inner side of the vessel. These zones result from the segregation of the alloying elements (C, Mn, Ni, Mo) and impurities (S, P) taking place during solidification of the material. They are called segregated zones (or ghost lines). They can reach 2 mm thick along the radius and 30 mm long through the circumferential direction. Their susceptibility to reversible temper embrittlement is mainly due to grain boundary phosphorus segregation triggering brittle intergranular fracture when the material is tested at low temperature. In this material like in other steels the influence of some other alloying elements (Mo, Mn...) is clearly significant and should also be taken into account. But phosphorus effect has proved to be predominant. The aim of the present study is therefore to find out a quantitative relationship between grain boundary phosphorus segregation and critical intergranular fracture stress. A synthetic steel with a chemical composition representative of an average segregated zone was prepared for the present study. A number of heat treatments were applied to reach different embrittlement conditions. Then brittle fracture properties were obtained by performing cryogenic fracture tests on notched tensile specimens while the corresponding grain boundary phosphorus levels were measured by Auger electron spectroscopy. Systematic fractographic observations were carried out. Moreover an attempt to determine the influence of temperature on the critical intergranular fracture stress was made

  13. Proximal tibia stress fracture with Osteoarthritis of knee − Radiological and functional analysis of one stage TKA with long stem

    Directory of Open Access Journals (Sweden)

    Soundarrajan Dhanasekaran

    2018-01-01

    Conclusion: TKA with long stem gives excellent outcome, irrespective of severity of arthritis associated with stress fracture. By restoring limb alignment and bypassing the fracture site, it facilitates fracture healing. Early detection and prompt intervention is necessary to prevent the progression to recalcitrant non-union or malunion.

  14. Relationships between fractures

    Science.gov (United States)

    Peacock, D. C. P.; Sanderson, D. J.; Rotevatn, A.

    2018-01-01

    Fracture systems comprise many fractures that may be grouped into sets based on their orientation, type and relative age. The fractures are often arranged in a network that involves fracture branches that interact with one another. Interacting fractures are termed geometrically coupled when they share an intersection line and/or kinematically coupled when the displacements, stresses and strains of one fracture influences those of the other. Fracture interactions are characterised in terms of the following. 1) Fracture type: for example, whether they have opening (e.g., joints, veins, dykes), closing (stylolites, compaction bands), shearing (e.g., faults, deformation bands) or mixed-mode displacements. 2) Geometry (e.g., relative orientations) and topology (the arrangement of the fractures, including their connectivity). 3) Chronology: the relative ages of the fractures. 4) Kinematics: the displacement distributions of the interacting fractures. It is also suggested that interaction can be characterised in terms of mechanics, e.g., the effects of the interaction on the stress field. It is insufficient to describe only the components of a fracture network, with fuller understanding coming from determining the interactions between the different components of the network.

  15. On the link between stress field and small-scale hydraulic fracture growth in anisotropic rock derived from microseismicity

    Science.gov (United States)

    Gischig, Valentin Samuel; Doetsch, Joseph; Maurer, Hansruedi; Krietsch, Hannes; Amann, Florian; Evans, Keith Frederick; Nejati, Morteza; Jalali, Mohammadreza; Valley, Benoît; Obermann, Anne Christine; Wiemer, Stefan; Giardini, Domenico

    2018-01-01

    To characterize the stress field at the Grimsel Test Site (GTS) underground rock laboratory, a series of hydrofracturing and overcoring tests were performed. Hydrofracturing was accompanied by seismic monitoring using a network of highly sensitive piezosensors and accelerometers that were able to record small seismic events associated with metre-sized fractures. Due to potential discrepancies between the hydrofracture orientation and stress field estimates from overcoring, it was essential to obtain high-precision hypocentre locations that reliably illuminate fracture growth. Absolute locations were improved using a transverse isotropic P-wave velocity model and by applying joint hypocentre determination that allowed for the computation of station corrections. We further exploited the high degree of waveform similarity of events by applying cluster analysis and relative relocation. Resulting clouds of absolute and relative located seismicity showed a consistent east-west strike and 70° dip for all hydrofractures. The fracture growth direction from microseismicity is consistent with the principal stress orientations from the overcoring stress tests, provided that an anisotropic elastic model for the rock mass is used in the data inversions. The σ1 stress is significantly larger than the other two principal stresses and has a reasonably well-defined orientation that is subparallel to the fracture plane; σ2 and σ3 are almost equal in magnitude and thus lie on a circle defined by the standard errors of the solutions. The poles of the microseismicity planes also lie on this circle towards the north. Analysis of P-wave polarizations suggested double-couple focal mechanisms with both thrust and normal faulting mechanisms present, whereas strike-slip and thrust mechanisms would be expected from the overcoring-derived stress solution. The reasons for these discrepancies can be explained by pressure leak-off, but possibly may also involve stress field rotation around the

  16. Relevance of adjacent joint imaging in the evaluation of ankle fractures.

    Science.gov (United States)

    Antoci, Valentin; Patel, Shaun P; Weaver, Michael J; Kwon, John Y

    2016-10-01

    Routinely obtaining adjacent joint radiographs when evaluating patients with ankle fractures may be of limited clinical utility and an unnecessary burden, particularly in the absence of clinical suspicion for concomitant injuries. One thousand, three hundred and seventy patients who sustained ankle fractures over a 5-year period presenting to two level 1 trauma centers were identified. Medical records were retrospectively reviewed for demographics, physical examination findings, and radiographic information. Analyses included descriptive statistics along with sensitivity and predictive value calculations for the presence of adjacent joint fracture. Adjacent joint imaging (n=1045 radiographs) of either the knee or foot was obtained in 873 patients (63.7%). Of those, 75/761 patients (9.9%) demonstrated additional fractures proximal to the ankle joint, most commonly of the proximal fibula. Twenty-two of 284 (7.7%) demonstrated additional fractures distal to the ankle joint, most commonly of the metatarsals. Tenderness to palpation demonstrated sensitivities of 0.92 and 0.77 and positive predictive values of 0.94 and 0.89 for the presence of proximal and distal fractures, respectively. Additionally, 19/22 (86.4%) of patients sustaining foot fractures had their injury detectable on initial ankle X-rays. Overall, only 5.5% (75/1370) of patients sustained fractures proximal to the ankle and only 0.2% (3/1370) of patients had additional foot fractures not evident on initial ankle X-rays. The addition of adjacent joint imaging for the evaluation of patients sustaining ankle fractures is low yield. As such, patient history, physical examination, and clinical suspicion should direct the need for additional X-rays. Level IV. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Bone strength estimates relative to vertical ground reaction force discriminates women runners with stress fracture history.

    Science.gov (United States)

    Popp, Kristin L; McDermott, William; Hughes, Julie M; Baxter, Stephanie A; Stovitz, Steven D; Petit, Moira A

    2017-01-01

    To determine differences in bone geometry, estimates of bone strength, muscle size and bone strength relative to load, in women runners with and without a history of stress fracture. We recruited 32 competitive distance runners aged 18-35, with (SFX, n=16) or without (NSFX, n=16) a history of stress fracture for this case-control study. Peripheral quantitative computed tomography (pQCT) was used to assess volumetric bone mineral density (vBMD, mg/mm 3 ), total (ToA) and cortical (CtA) bone areas (mm 2 ), and estimated compressive bone strength (bone strength index; BSI, mg/mm 4 ) at the distal tibia. ToA, CtA, cortical vBMD, and estimated strength (section modulus; Zp, mm 3 and strength strain index; SSIp, mm 3 ) were measured at six cortical sites along the tibia. Mean active peak vertical (pkZ) ground reaction forces (GRFs), assessed from a fatigue run on an instrumented treadmill, were used in conjunction with pQCT measurements to estimate bone strength relative to load (mm 2 /N∗kg -1 ) at all cortical sites. SSIp and Zp were 9-11% lower in the SFX group at mid-shaft of the tibia, while ToA and vBMD did not differ between groups at any measurement site. The SFX group had 11-17% lower bone strength relative to mean pkZ GRFs (phistory of stress fracture. Bone strength relative to load is also lower in this same region suggesting that strength deficits in the middle 1/3 of the tibia and altered gait biomechanics may predispose an individual to stress fracture. Copyright © 2016. Published by Elsevier Inc.

  18. The inclusion of weld residual stress in fracture margin assessments of embrittled nuclear reactor pressure vessels

    International Nuclear Information System (INIS)

    Dickson, T.L.; Bass, B.R.; McAfee, W.J.

    1998-01-01

    Analyses were performed to determine the impact of weld residual stresses in a reactor pressure vessel (RPV) on (1) the generation of pressure temperature (P-T) curves required for maintaining specified fracture prevention margins during nuclear plant startup and shutdown, and (2) the conditional probability of vessel failure due to pressurized thermal shock (PTS) loading. The through wall residual stress distribution in an axially oriented weld was derived using measurements taken from a shell segment of a canceled RPV and finite element thermal stress analyses. The P-T curve derived from the best estimate load analysis and a t / 8 deep flaw, based on K Ic , was less limiting than the one derived from the current methodology prescribed in the ASME Boiler and Pressure Vessel Code. The inclusion of the weld residual stresses increased the conditional probability of cleavage fracture due to PTS loading by a factor ranging from 2 to 4

  19. Quantifying Discrete Fracture Network Connectivity in Hydraulic Fracturing Stimulation

    Science.gov (United States)

    Urbancic, T.; Ardakani, E. P.; Baig, A.

    2017-12-01

    Hydraulic fracture stimulations generally result in microseismicity that is associated with the activation or extension of pre-existing microfractures and discontinuities. Microseismic events acquired under 3D downhole sensor coverage provide accurate event locations outlining hydraulic fracture growth. Combined with source characteristics, these events provide a high quality input for seismic moment tensor inversion and eventually constructing the representative discrete fracture network (DFN). In this study, we investigate the strain and stress state, identified fracture orientation, and DFN connectivity and performance for example stages in a multistage perf and plug completion in a North American shale play. We use topology, the familiar concept in many areas of structural geology, to further describe the relationships between the activated fractures and their effectiveness in enhancing permeability. We explore how local perturbations of stress state lead to the activation of different fractures sets and how that effects the DFN interaction and complexity. In particular, we observe that a more heterogeneous stress state shows a higher percentage of sub-horizontal fractures or bedding plane slips. Based on topology, the fractures are evenly distributed from the injection point, with decreasing numbers of connections by distance. The dimensionless measure of connection per branch and connection per line are used for quantifying the DFN connectivity. In order to connect the concept of connectivity back to productive volume and stimulation efficiency, the connectivity is compared with the character of deformation in the reservoir as deduced from the collective behavior of microseismicity using robustly determined source parameters.

  20. Brachymetatarsia of the Fourth Metatarsal, Lengthening Scarf Osteotomy with Bone Graft

    OpenAIRE

    Desai, Ankit; Lidder, Surjit; R. Armitage, Andrew; S. Rajaratnam, Samuel; D. Skyrme, Andrew

    2013-01-01

    A 16-year-old girl presented with left fourth metatarsal shortening causing significant psychological distress. She underwent lengthening scarf osteotomy held with an Omnitech® screw (Biotech International, France) with the addition of two 1 cm cancellous cubes (RTI Biologics, United States). A lengthening z-plasty of the extensor tendons and skin were also performed. At 6 weeks the patient was fully weight bearing and at one-year follow up, the patient was satisfied and discharged. A modifie...

  1. Numerical Evaluation and Optimization of Multiple Hydraulically Fractured Parameters Using a Flow-Stress-Damage Coupled Approach

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2016-04-01

    Full Text Available Multiple-factor analysis and optimization play a critical role in the the ability to maximizethe stimulated reservoir volume (SRV and the success of economic shale gas production. In this paper, taking the typical continental naturally fractured silty laminae shale in China as anexample, response surface methodology (RSM was employed to optimize multiple hydraulic fracturing parameters to maximize the stimulated area in combination with numerical modeling based on the coupled flow-stress-damage (FSD approach. This paper demonstrates hydraulic fracturing effectiveness by defining two indicesnamelythe stimulated reservoir area (SRA and stimulated silty laminae area (SLA. Seven uncertain parameters, such as laminae thickness, spacing, dip angle, cohesion, internal friction angle (IFA, in situ stress difference (SD, and an operational parameter-injection rate (IR with a reasonable range based on silty Laminae Shale, Southeastern Ordos Basin, are used to fit a response of SRA and SLA as the objective function, and finally identity the optimum design under the parameters based on simultaneously maximizingSRA and SLA. In addition, asensitivity analysis of the influential factors is conducted for SRA and SLA. The aim of the study is to improve the artificial ability to control the fracturing network by means of multi-parameteroptimization. This work promises to provide insights into the effective exploitation of unconventional shale gas reservoirs via optimization of the fracturing design for continental shale, Southeastern Ordos Basin, China.

  2. Influence of stress-induced deformations on observed water flow in fractures of the Climax Granitic Stock

    International Nuclear Information System (INIS)

    Wilder, D.G.

    1987-01-01

    Three examples of stress induced influence on fracture dominated hydrology were noted in drifts 1400 ft below surface in granite. Seepage into portions of shears near a fault zone and an adjoining drift, and mineralization of the joints were the three indicators of shear stress. Interpretation of these results are given

  3. Forefoot Adduction Is a Risk Factor for Jones Fracture.

    Science.gov (United States)

    Fleischer, Adam E; Stack, Rebecca; Klein, Erin E; Baker, Jeffrey R; Weil, Lowell; Weil, Lowell Scott

    Jones fractures are among the most common fractures of the foot; however, much remains unknown about their etiology. The purpose of the present study was to further examine the risk factors of forefoot and hindfoot alignment on Jones fractures using an epidemiologic study design. We used a retrospective, matched, case-control study design. Cases consisted of patients with acute, isolated Jones fractures confirmed on plain film radiographs seen at our institute from January 2009 to December 2013. Patients presenting with pain unrelated to metatarsal fractures served as controls. Controls were matched to cases by age (±2 years), gender, and year of presentation. Weightbearing foot radiographs were assessed for 13 angular relationships by a single rater. Conditional multivariable logistic regression was used to identify important risk factors. Fifty patients with acute Jones fractures and 200 controls were included. The only significant variables in the final multivariable model were the metatarsus adductus angle (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.08 to 1.25) and fourth/fifth intermetatarsal angle (OR 0.69, 95% CI 0.57 to 0.83)-both measures of static forefoot adduction. The presence of metatarsus adductus (defined as >15°) on foot radiographs was associated with a 2.4 times greater risk of a Jones fracture (adjusted OR 2.4, 95% CI 1.2 to 4.8). We have concluded that the risk of Jones fracture increases with an adducted forefoot posture. In our population, which consisted primarily of patients presenting after a fall (10 of 50; 20%) or misstep/inversion injury (19 of 50; 38%), the hindfoot alignment appeared to be a less important factor. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  4. A fracture mechanics model for iodine stress corrosion crack propagation in Zircaloy tubing

    International Nuclear Information System (INIS)

    Crescimanno, P.J.; Campbell, W.R.; Goldberg, I.

    1984-01-01

    A fracture mechanics model is presented for iodine-induced stress corrosion cracking in Zircaloy tubing. The model utilizes a power law to relate crack extension velocity to stress intensity factor, a hyperbolic tangent function for the influence of iodine concentration, and an exponential function for the influence of temperature and material strength. Comparisons of predicted to measured failure times show that predicted times are within a factor of two of the measured times for a majority of the specimens considered

  5. Fracture Mechanics

    CERN Document Server

    Zehnder, Alan T

    2012-01-01

    Fracture mechanics is a vast and growing field. This book develops the ba