Deconstructing forearm casting task by videos with step-by-step simulation teaching improved performance of medical students: is making working student's memory work better similar to a process of artificial intelligence or just an improvement of the prefrontal cortex homunculus?

PURPOSE: To compare two teaching methods of a forearm cast in medical students through simulation, the traditional method (Trad) based on a continuous demonstration of the procedure and the task deconstruction method (Decon) with the procedure fragmenting into its constituent parts using videos. METHODS: During simulation training of the below elbow casting technique, 64 medical students were randomized in two groups. Trad group demonstrated the entire procedure without pausing. Decon group received step-wise teaching with educational videos emphasizing key components of the procedure. Direct and video evaluations were performed immediately after training (day 0) and at six months. Performance in casting was assessed using a 25-item checklist, a seven item global rating scale (GRS Performance), and a one item GRS (GRS Final Product). RESULTS: Fifty-two students (Trad n = 24; Decon n = 28) underwent both day zero and six month assessments. At day zero, the Decon group showed higher performance via video evaluation for OSATS (p = 0.035); GRS performance (p < 0.001); GRS final product (p < 0.001), and for GRS performance (p < 0.001) and GRS final product (p = 0.011) via direct evaluation. After six months, performance was decreased in both groups with ultimately no difference in performance between groups via both direct and video evaluation. Having done a rotation in orthopaedic surgery was the only independent factor associated to higher performance. CONCLUSIONS: The modified video-based version simulation led to a higher performance than the traditional method immediately after the course and could be the preferred method for teaching complex skills.

Outcomes after primary ankle arthrodesis in recent fractures of the distal end of the tibia in the elderly: a systematic review.

PURPOSES: Management of distal tibia fractures in the elderly is complex. The results of conservative treatments may be disappointing and primary ankle arthrodesis is now regularly offered as an alternative. In this study, we aimed to review the outcomes of primary ankle arthrodesis for distal tibia fracture in the elderly. METHODS: We conducted a systematic review of the literature, from the Cochrane, MEDLINE, and Embase databases, on studies published in English and in French between 1950 and 2020. Only studies reporting the clinical results, the function, or the complications of primary ankle arthrodesis after ankle fracture in the elderly were included. RESULTS: We included nine studies. The total number of patients was 229: 21% of them (50/229) sustained open fractures and 41% (95/229) had three or more comorbidities. All the patients underwent a tibio-talo-calcaneal arthrodesis with a retrograde transplantar intramedullary nailing (TIMN): short nail in 52% (151/229) and long nail in 48% (78/229) of the cases. At a mean follow-up comprised between six and 21 months, 94.5% of patients (190/201) achieved bone union, 87% (123/140) recovered an ankle range of motion close to their pre-operative status, 19% (40/211) had a complication, and 11.3% (24/211) required a revision. The use of a short nail resulted in a higher rate of peri-implant complication (2%) as well as a higher rate of revision (12.4%). CONCLUSION: Primary ankle arthrodesis in recent fractures of the distal end of the tibia in the elderly frequently results in satisfactory results. The use of a long nail may be associated with a lower rate of implant specific complications.

Ankle osteonecrosis in fifty-one children and adolescent's leukemia survivors: a prospective randomized study on percutaneous mesenchymal stem cells treatment.

PURPOSE: Corticoid treatment associated with haematologic treatments can lead to ankle osteonecrosis in children's survivors of acute leukemia (ALL). Based on the efficiency of mesenchymal stem cells (MSCs) in hip osteonecrosis, we performed an evaluation of this treatment in 51 children and adolescents who had symptomatic ankle osteonecrosis after therapy for haematologic cancer. MATERIAL AND METHODS: The 51 patients had a total of 79 osteonecrosis sites on MRI, with 29 talus sites, 18 metaphyseal tibia sites, 12 epiphyseal tibia sites, eight calcaneus sites, six fibula sites, four navicular sites, and two cuboid sites. In this prospective randomized trial, 37 ankles were addressed for cell therapy, 37 others for core decompression alone, and 20 were considered as a control group without treatment. We analyzed the outcome of this treatment osteonecrosis, the number and characteristics of bone marrow mesenchymal cells (MSCs) that could be transplanted, and the risks of tumorigenesis in these patients with haematologic cancers. The patients were operated on over a period of ten years from 2000 to 2010 and were monitored through December 31, 2019. RESULTS: Despite a normal systemic blood cells count, MSCs in the iliac crest (counted as CFU-F) were in low number (1021 MSCs/mL; range 314-3015) and were of host origin after even allogeneic bone marrow transplantation. Better clinical outcomes (pain, foot and ankle deformity) and osteonecrosis repair on MRI with absence of collapse were obtained in ankles that received cell therapy as compared with those with core decompression alone or those without initial surgery. No tumour was found on MRI at the sites of injection and this study found no increased risk of recurrence or of new cancer in this population after an average follow-up of 15 years. CONCLUSIONS: These results suggest that autologous MSCs can improve the quality of life of leukemia survivors with ankle osteonecrosis.

Knee Osteonecrosis: Cell Therapy with Computer-assisted Navigation.

BACKGROUND: The knee is the second-most common location for osteonecrosis, although it is affected much less often than the hip. Core decompression by precise drilling into ischemic lesions of the femoral condyle while remaining extra-articular is a challenge, particularly in obese patients. For cell therapy, exact localization of the injection point is important to avoid intra-articular injection. METHODS: The precision of drilling with computer-based navigation was compared to that of conventional fluoroscopy-based drilling. A prospective, randomized study was conducted using both surgical trainees without experience and expert surgeons. First, participants performed the surgical task (core decompression) on a cadaver knee using fluoroscopic guidance or computer-based navigation. Performance was determined by the radiographic analysis of trocar placement. Next, 12 consecutive patients with bilateral symptomatic secondary (corticosteroids) osteonecrosis without collapse were included in a clinical prospective, randomized, controlled study. The 24 knees were treated using conventional fluoroscopy with expert surgeons on one side and computer-based navigation with surgical trainees on the contralateral side. Bone marrow aspirated from the two iliac crests was mixed before concentration. Each side received the same volume of concentrated bone marrow and the same number of cells (95,000 ± 25,000 cells; counted as CFU-F). RESULTS: In the cadaver tests, the distance to the desired center-point of the lesion in the navigated group (1.6 mm) was significantly less than that in the control group (5.9 mm; p<0.001). Significant differences were also found in the number of drilling corrections (p<0.001), the radiation time needed (p<0.001), the risk of intra-articular penetration, and the risk of ligament injuries. In patients, computer navigation achieved results closer to the ideal position of the trocar, with better trocar placement in terms of tip-to-subchondral distance and ideal center position within the target for injection of stem cells. At the most recent follow-up (5 years), an increase in precision with computer-assisted navigation resulted in less collapse (4 vs. 1) and better volume of repair (11.4 vs 4.2 cm3) for knees treated with the computer-assisted technique. Failures were related to missing the target with intra-articular penetration. CONCLUSIONS: Computer-assisted navigation improved precision with less radiation. The findings of this study suggest that computer navigation may be safely used in a basic procedure for the injection of stem cells in knee osteonecrosis.

Safety of simultaneous versus staged bilateral opening-wedge high tibial osteotomy with locked plate and immediate weight bearing.

PURPOSE: With advances in technology and particularly locked screws, patients with high tibial osteotomy (HTO) are frequently allowed full weight bearing for a  unilateral procedure. We are aware of no reports comparing the safety of a simultaneous bilateral HTO with staged bilateral HTO. The purpose of this study was to retrospectively compare these two strategies. MATERIAL AND METHODS: Ninety patients were treated with bilateral HTO surgery for osteoarthritis from 2009 to 2013; they had opening-wedge HTO and fixed with the same plate fixation and locked screws. A comparison of the outcomes after simultaneous bilateral HTO (35 patients) and after sequential staged bilateral HTO (55 patients) was performed. We considered four measures of medical safety: hypotension, serious intra-operative adverse event, heterologous blood transfusion, and thrombophlebitis. We considered also four measures of orthopaedic safety: infection, patient's inability to walk full weight bearing, changes in correction, and nonunion. RESULTS: For the same duration of operation, the duration of anaesthesia and the time in the operating room were 35% longer for patients having a staged bilateral HTO. Blood loss was higher in patients undergoing simultaneous bilateral HTO compared with those who underwent a staged bilateral HTO. For patients undergoing simultaneous bilateral HTO, thrombophlebitis frequency and length of anticoagulation were lower than the sum of each event in the staged bilateral HTO. The patients with simultaneous bilateral HTO had a longer total period of time for crutches than patients with staged bilateral HTO. Patients in the simultaneous bilateral cohort did not develop an infection within one year as patients in the planned-stage cohort. The simultaneous bilateral cohort had a lower rate of delayed union than the planned-stage cohort did. CONCLUSION: On the basis of this analysis, simultaneous bilateral HTO is a reasonable treatment option. Individuals who undergo staged bilateral HTO face the risk of complications twice, in addition to two hospitalizations. Patients who undergo simultaneous bilateral HTO have a higher risk of blood transfusion.

Local infiltration analgesia versus interscalene nerve block for postoperative pain control after shoulder arthroplasty: a prospective, randomized, comparative noninferiority study involving 99 patients.

BACKGROUND: The aim of this study was to compare the efficacy of local infiltration analgesia (LIA) and interscalene nerve block (ISB) for early postoperative pain control after total shoulder arthroplasty (TSA). The hypothesis was that LIA is not inferior to ISB. METHODS: A prospective, randomized controlled study was performed in 2014-2016. All patients who underwent TSA for shoulder osteoarthritis were included. Patients in the ISB group received a continuous infusion of 0.2% ropivacaine by perineural catheter for 48 hours. The surgeon injected 110 mL of 0.2% ropivacaine, 30 mg of ketoprofen, and 0.5 mg of epinephrine before TSA in the LIA group and inserted a catheter into the glenohumeral joint. The next morning, 10 mL of 0.2% ropivacaine, 30 mg of ketoprofen, and epinephrine were injected through the catheter, which was then removed. The primary outcome was the mean shoulder pain score for the 48-hour postoperative period on a numerical scale (0-10). The secondary outcomes were postoperative opioid requirements, complications, and shoulder function at the 1-month follow-up visit. The sample size was calculated for a noninferiority study. RESULTS: The study included 99 patients (50 LIA and 49 ISB patients) with a mean age of 72 ± 9.6 years. Although no significant difference in the mean pain score was found between the 2 groups for the 48-hour postoperative period (1.4 ± 0.9 for LIA vs 1.7 ± 1 for ISB, P = .19), the LIA group had significantly less severe pain (P = .003) and less opioid consumption (P = .01) in the recovery room. No complications occurred. A negative but nonsignificant correlation was found between postoperative pain and Constant score at the 1-month follow-up. CONCLUSION: LIA is not less effective than ISB for early postoperative pain control after TSA.

Targeting Core Decompression and Cell Therapy Injection of Hip Osteonecrosis with Computer-Assisted Navigation.

PURPOSE: Surgical treatment of hip osteonecrosis with stem cell therapy is a new procedure in which cells are injected with a trocar under fluoroscopic guidance. Proper surgical technique to obtain appropriate placement of the trocar in the center of the osteonecrosis is sometimes difficult and can require additional radiation exposure until the surgeon is satisfied with the trocar position. This study describes an improvement of this procedure using computer-assisted navigation. METHODS: A prospective, randomized study was conducted on cadavers using surgical trainees with no experience and one expert surgeon in surgical core decompression. During a training session, 3 novice surgeons underwent a test by performing the surgical task (core decompression) on a cadaver hip using fluoroscopic guidance. These trainee surgeons then placed the Kirschner wire under computer-assisted navigation. Osteonecrosis was defined as a target volume situated on the superior and anterior part of the femoral head. Performance during the tests was evaluated by radiographic analysis of trocar placement and by the measurement of radiation exposure. RESULTS: During the cadaver session, computer-assisted navigation achieved a better match to the ideal position of the trocar, with better trocar placement in terms of the tip-to-subchondral distance and the ideal center position. Computer-assisted navigation was associated with fewer attempts to position the trocar, a shorter duration of fluoroscopy, and decreased radiation exposure compared to surgery performed under conventional fluoroscopy. CONCLUSIONS: The findings suggest that computer-assisted navigation may be safely used to train surgical novices in core decompression. This technique avoids the use of both live patients and harmful radiation. For expert surgeons, computer-assisted navigation might improve precision with less radiation, which might be desirable in cell therapy.

Vitamin D: part II; cod liver oil, ultraviolet radiation, and eradication of rickets.

PURPOSE: After Glisson's description of rickets, it took two centuries to realize that rickets was due to the absence of antirachitic nutrients in the diet or lack exposure of the skin to ultraviolet rays. This bone disease caused by vitamin D deficiency was one of the most common diseases of children 100 years ago. This paper explores how the definition, diagnosis, and treatment of rickets shifted in the first decades of the twentieth century. MATERIAL AND METHODS: Although benefits of cod liver oil as food were known as early as the seventh century, cod liver oil was only proposed as medicinal for rickets in Northern Europe at the end of the eighteenth century. The relationship between rickets and nutritional deficiency was suspected and demonstrated between 1880 and 1915, at the same time of the discovery of other vital substances (vitamins) needed to prevent beriberi, scurvy, and pellagra. Understanding that the lack of photosynthesized vitamin D or the lack of dietary vitamin D was a similar risk of rickets was an important turn in the comprehension of the disease. We look at the sequence and turn of events related to the discovery of vitamin D. RESULTS: Rickets has been recognized first as a disease of urban living people. Cod liver oil had been used since 1700 as a nonspecific treatment for a range of diseases. Generations of children in cities of the north of Europe had learned to hate the taste and smell of the black oily liquid and then grown up to be parents who, in turn, hated to force it down their children's throats. Occasional papers before 1900 pointed to its efficacy for rickets, and most textbooks of the early 1900s mentioned it only as a treatment option. The discovery in the early 1900s that artificial and natural ultraviolet rays had both antirachitic activity allowed to produce antirachitic foods just by food irradiation with artificial ultraviolet irradiation. Clinical guidelines were adopted to propose exposure to sunlight or to artificial ultraviolet radiation to prevent rickets in children. By the mid-1920s, rickets was promoted as universal, at times invisible to non-experts, but present to some degree in nearly every young child regardless of race or class. It was thus used to promote the young disciplines of preventive medicine, pediatrics, and public health. Innovative advances were made in the understanding of vitamin D synthesis from 1915 to 1935. A public health campaign of the 1930s was a success to eradicate rickets, using irradiated ergosterol from yeast to enrich milk and other foods with vitamin D, ensuring that the general population was consuming sufficient vitamin D. CONCLUSION: Rickets therefore provides an excellent window into the early politics of preventive health and the promotion of targeted interventions in the world. It is also a relevant historical counterpoint for current debates over the role of risk factors (absence of light or sun) for disease (today's so-called "lifestyle" diseases).

Vitamin D history part III: the "modern times"-new questions for orthopaedic practice: deficiency, cell therapy, osteomalacia, fractures, supplementation, infections.

PURPOSE: The nutritional basis for rickets was described between 1880 and 1915, at the same period of discovery of other "vital substances" or vitamins. In contrast, rickets could also be prevented or cured by sunshine. But as the capacity to produce vitamin D depends on exposure to ultraviolet B rays (UVB) from sunlight or artificial sources, vitamin D became one of the most frequently used "drugs" in the twentieth century to compensate for insufficient exposure to UVB of humans. Furthermore, as the understanding of vitamin D metabolism grew during the twentieth century, other concerns than rickets occurred for the orthopaedic surgeon: In recent history, deficiency is explored as being an associated factor of different bone pathologies as fracture or prosthetic infection. The aim of this review is to analyze these new data on vitamin D. MATERIALS AND METHODS: During the twentieth century, there were many concerns for the orthopaedic surgeon: sources and synthesis of vitamin D, regulation of the calcium deposition process for both children and adults, when vitamin D deficiency is observed, and what the best method of vitamin D supplementation is. As target genes regulated by vitamin D are not limited to those involved in mineral homeostasis, orthopedists recently discovered that vitamin D might prevent periprosthetic infection. RESULTS: The primary source (80%) of vitamin D is dermal synthesis related to the sun. Dietary sources (20%) of vitamin D are fat fishe, beef, liver, and eggs. Vitamin D is produced industrially to be used in fortified foods and supplements. Maintenance of skeletal calcium balance is mediated through vitamin D receptors. Progenitor cells, chondrocytes, osteoblasts, and osteoclasts contain these receptors which explains the role of vitamin D in cell therapy, in the prevention of rickets and osteomalacia. Despite fortified foods, the prevalence of deficiency remains endemic in north latitudes. However, the definition of vitamin D insufficiency or deficiency remains controversial. Vitamin D has been evaluated in patients undergoing fractures and elective orthopaedic procedures Although supplementation may not be able to prevent or cure all the orthopaedic pathologies, oral supplementation is able to improve the vitamin D levels of deficient patients. These vitamin D level improvements might be associated with better functional and clinical outcomes after some surgical procedures and improvement of immunity to decrease the risk of infection in arthroplasties. CONCLUSION: Vitamin D deficiency is frequent and concerns millions of people in the world. It is therefore normal to find hypovitaminosis in various orthopaedic populations including trauma and arthroplasties. However, we do not know exactly if this phenomenon only reflects the general prevalence of vitamin D deficiency or has an influence on the outcome of some pathologies on specific populations at risk. After the success of treatment of rickets, it is disappointing that we are still wondering in the twenty-first century whether supplementation of a substance synthetized millions of years ago by plankton and necessary for growth of all the animals may improve (or not) clinical and functional outcomes of a simple fracture in humans.

Long-Term Results of the "Horseman" Procedure for Severe Idiopathic Flatfoot in Children: A Retrospective Analysis of 41 Consecutive Cases With Mean 8.9 Year Duration of Follow-Up.

The "horseman" procedure is a surgical technique used to correct the talocalcaneal joint displacement of severe idiopathic flatfoot in children while maintaining the reduction with a temporary talocalcaneal screw. While this technique has been used since the early 1960s, very little has been reported on its results. Our objectives were to estimate the correction, functional results, and postoperative complications of the "horseman" procedure. We conducted a retrospective study on 23 consecutive patients (41 cases) who underwent the "horseman" procedure for a talocalcaneal joint displacement. Mean follow-up was 8.9 (range 1 to 28) years, and 8 patients (12 feet) had reached bone maturity at last follow-up. Mean age at surgery was 6.6 (range 4 to 9.5) years. At last follow-up, all the patients were asymptomatic except 2 [8.7%] (4 [9.8%] cases). The talocalcaneal divergence on anteroposterior and lateral radiographic views was reduced by 8.9° and 11.4°, respectively, after the surgery, and the correction was maintained with loss of 0.7° and 2.9°, respectively, at final follow-up. The talonavicular coverage angle was reduced by 25° without loss of correction at last follow-up. The calcaneal pitch angle did not change after the surgery. Mean American Orthopedic Foot and Ankle Society score increased from 88.7 of 100 (63 of 100 to 93 of 100) preoperatively to 99 of 100 (97 to 100 of 100) at last follow-up. No major complication occurred. The "horseman" procedure allows an immediate and lasting correction of severe idiopathic flatfoot in children.

Vitamin D: part I; from plankton and calcified skeletons (500 million years ago) to rickets.

The vitamin D history started early in the evolution of life (billion years ago) as a photochemical reaction producing an inert molecule. During the early evolution of vertebrates, this molecule became essential for calcium and bone homeostasis of terrestrial animals and arrived to the status of hormone. Phytoplankton, zooplankton, and most plants and animals that are exposed to sunlight have the capacity to make vitamin D. Vitamin D is critically important for the development, growth, and maintenance of a healthy skeleton from birth until death. The major function of vitamin D is to maintain calcium homeostasis. It accomplishes this by increasing the efficiency of the intestine to absorb dietary calcium. When there is inadequate calcium in the diet to satisfy the body's calcium requirement, vitamin D communicates to the osteoblasts that signal osteoclast precursors to mature and dissolve the calcium stored in the bone. The typical "vitamin D-deficiency" disorder was observed for growing children in the west and south of England in the early 1600s. This disease was described by Glisson and named "rickets" (known also as "the English disease") and was observed with epidemic proportions in northern Europe and North America. The corrections of deformities of rickets were at the origin of the name "orthopedia" and of the technique of osteotomies.

What is the rate of patients undergoing a total hip arthroplasty after core decompression and insertion of a tantalum rod in osteonecrosis of the femoral head: a systematic review.

PURPOSE: Core decompression (CD) may be effective when performed during the early stages of osteonecrosis of the femoral head (ONFH). Tantalum may be added as a rod that would allow putting some mechanical constraints on the femoral head. We aimed to estimate the rate of total hip arthroplasty after CD and insertion of a tantalum rod during early stages of OFNH. METHODS: We searched systematically Medline via PubMed and the Cochrane Library. Our primary endpoint was the rate of patients undergoing a total hip arthroplasty after CD and insertion of a tantalum rod. Secondary endpoints were the delay between the initial surgery and the arthroplasty, the functional improvement, and the rate of complications. RESULTS: We included seven  studies reporting the results of 232 patients (297 hips) that were operated on by CD and insertion of a tantalum rod. At a mean follow-up of 26.97 months, 24.63% of the included hips underwent a hip arthroplasty (6-56%, SD = 17.34%). The mean delay between the initial surgery and the arthroplasty was 14.94 months (10.20-22.90; SD = 5.25), the mean improvement of Harris Hip Score was 27.66 (20.20-36.90; SD = 6.48), and the mean rate of femoral fracture was 2.43% (0-13%, SD = 4.89%). CONCLUSION: CD and insertion of a tantalum rod may represent a solution in order to improve the mechanical support and to give a rate of conversion in arthroplasty that is acceptable.

Interest of short implants in hip arthroplasty for osteonecrosis of the femoral head: comparative study "uncemented short" vs "cemented conventional" femoral stems.

PURPOSES: Osteonecrosis of the femoral head (ONFH) is a dramatic condition resulting in joint destruction in the late stages. Total hip arthroplasty allows function recovery with satisfactory implant survival. Recently, the use of uncemented short stems has been suggested to improve the conservation of bone stock. METHODS: We performed a retrospective study on 16 hip arthroplasties-11 patients-implanted for ONFH between 2008 and 2017. We aimed to compare the outcomes of the two types of arthroplasty-"uncemented short" vs "cemented conventional" femoral stem-in terms of pain (visual analogue scale), function (Harris Hip Score), and survival (radiography). RESULTS: We included six  "uncemented short" and ten "cemented conventional" femoral stems. Mean pre-operative EVA was 7.5 and the mean HHS was 40.3. At last follow-up of seven years, mean VAS was 1.2 (SD ± 0.83) in the "uncemented short" group and 1.6 (SD ± 0.97) in the "cemented conventional" group. Mean HHS was 94 (SD ± 0.81) in the "uncemented short" group and 92.6 (SD ± 2.69) in the "cemented conventional" group. However, radiographic analysis revealed a lower stress shielding in the "uncemented short" stem group. One complication occurred (hip dislocation in the "cemented conventional" stem group). CONCLUSION: Uncemented short stems total hip arthroplasties may be an interesting alternative to more conventional implants with similar functional results but less stress shielding and a bone stock economy in this young population of patients.

Higher prevalence of periprosthetic fractures with ceramic on polyethylene hip bearing compared with ceramic on ceramic on the contralateral side: a forty year experience with hip osteonecrosis.

PURPOSE: It is unclear whether late THA periprosthetic femoral fractures are related to a mechanical mechanism that decreases strength of the femur (for example, loosening) or to a biological problem as osteolysis. It is also unknown if ceramic on ceramic bearing couples decrease the risk of late periprosthetic fractures as a result of the absence of wear and osteolysis. MATERIAL AND METHODS: We therefore asked whether the cumulative long-term fractures were different according to the couple of friction ceramic on ceramic or ceramic on polyethylene in 327 patients (654 hips) with bilateral THA (one ceramic-ceramic, and the contralateral ceramic-polyethylene) who had THA with cemented stems performed between from 1978 to 2000 for osteonecrosis. RESULTS: There were two intra-operative fractures (0.3%). The median follow-up was 22 years (range, 15-40 years), and at the most recent follow-up, the cumulative number of late (after 7 years of follow-up) post-operative fractures was 32 (5% of 654 hips). Fractures were unilateral, which means for the 327 patients, a 10% rate of fractures. Periprosthetic fractures increased in number with follow-up: seven fractures (1% of 654 hips) occurred within ten years of THA implantation, 20 (3%) within 20 years, 26 (4%) within 30 years, and 32 (5%) within 40 years. The risk of fracture was influenced (p < 0.001) by the bearing surfaces at the time of prosthetic implantation, low (0.3%) for ceramic on ceramic (1/32 fractures; 1/327 hips), high (10%) for ceramic on PE (31/32 fractures; 31/327 hips). CONCLUSION: In summary, when the contralateral hip of the same patient is the control, after 40 years of follow-up, post-operative fractures occur 30 times more often on the side with PE cup than on the side with ceramic/ceramic bearing.

Subchondral stem cell therapy versus contralateral total knee arthroplasty for osteoarthritis following secondary osteonecrosis of the knee.

PURPOSE: Total knee arthroplasty (TKA) implanted in patients with secondary osteonecrosis (ON) related to corticosteroids have relatively poor outcome (20% revision rate) at a mean follow-up of only eight years. With the hypothesis that subchondral bone marrow injection might improve knees in these patients, we evaluated 30 patients who had bilateral knee osteoarthritis with severe joint space narrowing and received TKA in one knee and subchondral bone marrow concentrate injection in the contralateral knee. MATERIAL AND METHODS: A prospective randomized controlled clinical trial was carried out in 60 knees of 30 patients (mean age 28 years, 18-41) who presented bilateral osteoarthritis secondary to knee ON related to corticosteroids in relation with different severe medical conditions. During the same anesthesia, one knee received TKA; for the other knee, a bone marrow graft containing an average of 6500 MSCs/mL (counted as CFU-F, range 3420 to 9830) was delivered to the subchondral bone of the femur and tibia. The length of anesthesia related to each procedure (bone marrow aspiration and subchondral injection of concentrated bone marrow versus total knee arthroplasty) was measured. Peri-operative outcomes, morbidity, complications, and safety of the two procedures were compared. Subsequent admissions for revision surgery were identified. At the most recent follow-up (average of 12 years, range 8 to 16 years), clinical outcomes of the patient (Knee Society score) were obtained along with radiological imaging outcomes (MRIs for knees with subchondral bone marrow injection). RESULTS: Anesthesia related to the TKA side was longer than for the cell therapy group. Medical and surgical complications were more frequent after TKA. A higher number of thrombophlebitis was observed on the side with TKA (15%) versus none on the side with cell therapy (0%). At the most recent follow-up (average of 12 years, range 8 to 16 years), six (out of 30) TKA knees needed subsequent surgery versus only one with cell therapy. The Knee Score had improved and remained similar in the TKA and cell therapy groups (respectively 80.3 points ± 11 versus 78.3 ± 23); 21 patients preferred the knee with cell therapy and 9 preferred the knee with TKA. Knees with cell therapy had improvement on cartilage and bone marrow lesions observed at the site of bone marrow subchondral injection. CONCLUSIONS: Subchondral autologous bone marrow concentrate was an effective procedure for treating young patients with knee osteoarthritis following secondary ON of the knee related to corticosteroids with a lower complication rate and a quicker recovery as compared with TKA.

Dual-mobility implants prevent hip dislocation following hip revision in obese patients.

PURPOSE: Revision total hip arthroplasty (THA) is associated with increased rates of dislocation in obese patients. It is not known whether dual-mobility implants decrease dislocation in these patients with obesity. METHODS: We retrospectively reviewed two groups of revision THAs to compare the dislocation rate between 32 obese patients (BMI >30 kg/m2) with standard cups, and 35 obese patients (BMI >30 kg/m2) with dual-mobility cups. All patients received the same implants except for diameter head (32-mm head with standard cups and 28-mm head with dual mobility) and had the same cemented stem that was not changed at revision. The patients were followed at routine intervals and were specifically queried about dislocation. The two groups were similar in terms of age, gender, causes of revision and follow-up since the primary arthroplasty. RESULTS: With standard liners, more hips in obese patients dislocated than did hips in obese patients who received dual-mobility implants. The number of dislocations in standard hips was at one year follow-up 15.6 % (5 of 32) compared with 0 % in dual-mobility hips and was at five year follow-up 21.8 % (7 of 32) compared with 2.8 % (1 of 35). After a mean follow-up of seven years no cases of loosening were found. Five patients in the obese group with a standard liner underwent re-revision surgery, the additional re-operations being necessary to treat recurrent postoperative dislocation. CONCLUSIONS: Obese patients should be counselled about the important risk of dislocation that occurs with standard liners after revision THA. Dual-mobility liners in these patients with hip revision is an efficient technique to prevent post-operative hip dislocation.

Contra-lateral hip fracture in the elderly: are decreased body mass index and skin thickness predictive factors?

PURPOSE: A correlation between soft tissue thickness and osteoporosis has been suggested. We aimed to estimate if a low body mass index (BMI) and/or a decrease of skin thickness could estimate the risk of contra-lateral hip fracture. METHODS: First, we performed a retrospective analysis of 1268 patients treated for a hip fracture. The 146 patients who had a contra-lateral hip fractures-study group-were compared with the 1078 patients who did not-control group. Four BMI categories were considered: obese, overweight, normal weight and low weight. Second, we enrolled prospectively 1000 consecutive patients in the emergency department. History of fractures, BMI, and skin aspect on the dorsum of both hands-classified as severe decrease thickness, moderate decrease thickness or normal-were recorded. RESULTS: pt?>In the first part, we found that patients with contra-lateral fractures had a significantly lower BMI than those in the control group (22.2 Vs 26.5 kg/m2, p = 0.01). In the second part, 48 on 1000 patients had a hip fracture. Among them, six had a contra-lateral fracture. BMI was 23.4 kg/m2 in bilateral hip fractures, 33.68 kg/m2 in the unilateral fracture group, and 28.04 kg/m2 in the non-fracture group (p = 0.04). Finally, patients with contra-lateral hip fractures had a severe decrease thickness of the skin. CONCLUSION: A low BMI and a decreased skin thickness increase independently the risk of fractures by three times. When associated, they increase the risk of fracture risk by five times. This combination had a sensitivity at 71 % and a specificity at 90 % for predicting hip fracture.

Effect of anatomic site and irradiation on the rates of revision and infection of allograft-prosthesis composites after resection of a primary bone tumor: a meta-analysis.

INTRODUCTION: Allograft-prosthesis composite reconstruction after resection of a primary bone tumor may have theoretical advantages, such as restoration of bone stock and soft tissue attachments. However, the reported results of APC of different anatomical sites differ widely. We conducted a meta-analysis to estimate the revision and infection rates associated with allograft-prosthesis composite (APC) reconstructions after resection of a primary bone tumor. We looked for variables, such as anatomic sites and irradiation of the allograft, associated with these outcomes. MATERIALS AND METHODS: We searched Medline, EMBASE, and Cochrane Library. The primary outcome was the revision rate, and the secondary outcome was the infection rate. Random effects meta-analyses of single proportions were used to estimate pooled rates of events. Meta-regression models were built to assess the effect of moderators on relevant both outcomes. RESULTS: Thirty-one studies were included: 9 about acetabulum APC, 9 about proximal femur APC, 4 about proximal tibia APC, and 9 about proximal humerus APC. The revision rates ranged from 16 % (95 % CI 10-25 %) for proximal humerus to 38 % (95 % CI 26-52 %) for acetabulum, and were significantly different between anatomic sites (p = 0.028). The infection rates ranged from 8 % (95 % CI 4-16 %) for proximal humerus to 23 % (95 % CI 16-33 %) for proximal tibia and 23 % (95 % CI 15-35 %) acetabulum APCs, and were significantly different between anatomic sites (p = 0.008). Finally, we found that irradiation of the allograft was significantly associated with revision rates (p = 0.033) and infection rates (p < 0.001). CONCLUSIONS: Results of an APC reconstruction after resection of a primary malignant bone tumor vary significantly between anatomic sites and after irradiation of the allograft.

Treatment of pigmented villonodular synovitis of the knee.

PURPOSE: We aimed to determine the rate of local recurrence, the rate of postoperative complications, and the functional outcome at final follow-up of surgical and nonsurgical treatment approaches for pigmented villonodular synovitis (PVNS) of the knee. METHODS: Medline, Embase, and the Cochrane Library were systematically searched for studies that reported the results of treatment for any type of PVNS between January 1, 1950, and August 1, 2013. Two authors extracted the data independently using predefined data fields including study quality indicators. RESULTS: Sixty studies (1,019 patients) met the inclusion criteria. Thirty-five presented data on the treatment of localized pigmented villonodular synovitis (LPVNS), 40 on diffuse pigmented villonodular synovitis (DPVNS), 1 on extra-articular LPVNS, and 7 on DPVNS with extra-articular involvement. Many therapeutic options were reported. Depending on these options, DPVNS recurred in 8% to 70% of the series and LPVNS recurred in 0% to 8% of the series. For LPVNS, the 2 most-reported options were open localized synovectomy and arthroscopic local synovectomy. Between these 2 courses of treatment, no difference was found in terms of local recurrence (8.7% for open synovectomy and 6.9% for arthroscopic synovectomy) and postoperative complications (<1% for open synovectomy and 0% for arthroscopic synovectomy). For DPVNS, the 2 most-reported options were open total synovectomy and arthroscopic total synovectomy. Between these 2 courses of treatment, no difference was found in terms of local recurrence (22.6% for open synovectomy and 16.1% for arthroscopic synovectomy). However, we found a lower rate of reported complications between open synovectomy (19.3%) and arthroscopic synovectomy (0%). Internal irradiation or external beam radiation as an adjuvant treatment to surgical synovectomy seemed to decrease the rate of local recurrence in DPVNS cases with a high risk of recurrence. Finally, we found a great heterogeneity in the way the functional results were reported, and no valid conclusion could be made based on the data we extracted. CONCLUSIONS: We found no difference in local recurrence rates after open or arthroscopic surgery for either LPVNS or DPVNS. However, a lower rate of postoperative complications was reported after arthroscopic surgery for DPVNS. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV therapeutic studies.

Induced membrane for treatment of critical sized bone defect: a review of experimental and clinical experiences.

PURPOSE: The purpose of this study was to review experimental and clinical experiences about the use of an induced membrane to address critical bone size defect of the limbs. METHODS: From a review of published experimental and clinical data and from our clinical experience, we present the key data about the use of an induced membrane to address critical bone size defect of the limbs. RESULTS: After reviewing the concept of critical sized bone defect, we present the different indications of an induced membrane, the key points of the surgical technique and the strategy of bone grafting given the indication, localization and importance of the critical sized bone defect. Finally, we discuss the perspective of the use of an induced membrane with various bone substitutes. CONCLUSIONS: The use of an induced membrane to treat critical sized bone defects of the limbs is a simple, reliable and reproducible technique. Certain technical steps should be pointed out and observed with great caution in order to avoid any pitfalls. This technique will probably be a key step for facilitating bone inclusion of new bone substitutes proposed by recent bioengineering.