Impact of the COVID-19 lockdown period on adult musculoskeletal injuries and surgical management: a retrospective monocentric study.

The coronavirus disease 2019 (COVID-19) pandemic has led to the worldwide implementation of unprecedented public protection measures. On the 17th of March, the French government announced a lockdown of the population for 8 weeks. This monocentric study assessed the impact of this lockdown on the musculoskeletal injuries treated at the emergency department as well as the surgical indications. We carried out a retrospective study in the Emergency Department and the Surgery Department of Nantes University Hospital from 18 February to 11 May 2020. We collected data pertaining to the demographics, the mechanism, the type, the severity, and inter-hospital transfer for musculoskeletal injuries from our institution. We compared the 4-week pre-lockdown period and the 8-week lockdown period divided into two 4-week periods: early lockdown and late lockdown. There was a 52.1% decrease in musculoskeletal injuries among patients presenting to the Emergency Department between the pre-lockdown and the lockdown period (weekly incidence: 415.3 ± 44.2 vs. 198.5 ± 46.0, respectively, p < .001). The number of patients with surgical indications decreased by 33.4% (weekly incidence: 44.3 ± 3.8 vs. 28.5 ± 10.2, p = .048). The policy for inter-hospital transfers to private entities resulted in 64 transfers (29.4%) during the lockdown period. There was an increase in the incidence of surgical high severity trauma (Injury Severity Score > 16) between the pre-lockdown and the early lockdown period (2 (1.1%) vs. 7 (7.2%), respectively, p = .010) as well as between the pre-lockdown and the late lockdown period (2 (1.1%) vs. 10 (8.3%), respectively, p = .004). We observed a significant increase in the weekly emergency department patient admissions between the early and the late lockdown period (161.5 ± 22.9, 235.5 ± 27.7, respectively, p = .028). A pronounced decrease in the incidence of musculoskeletal injuries was observed secondary to the lockdown measures, with emergency department patient admissions being halved and surgical indications being reduced by a third. The increase in musculoskeletal injuries during the late confinement period and the higher incidence of severe trauma highlights the importance of maintaining a functional trauma center organization with an inter-hospital transfer policy in case of a COVID-19s wave lockdown.

Functional assessment of transplantar nailing for ankle fracture in the elderly: 48 weeks' prospective follow-up of 14 patients.

INTRODUCTION: Retrograde transplantar intramedullary nailing (TIMN) is a recently described option for ankle fracture in elderly patients with multiple comorbidity contraindicating classical internal fixation. The main objective of the present study was to assess mobility after TIMN for ankle fracture in the elderly. The secondary objective was to assess complications. HYPOTHESIS: Retrograde TIMN provides reliable fixation of ankle fracture in the elderly, enabling early resumption of walking. MATERIAL AND METHODS: Fourteen patients, with a mean age of 79.6years (range: 65-99years), with fracture of the ankle or tibial pilon treated by retrograde TIMN, were prospectively included over a 1-year period (2014-2016). Full weight-bearing with walking cast boot was authorized as of day 1. Mobility was assessed on Parker score in consultation at 6, 12, 24 and 48 weeks. RESULTS: Ten patients were followed up. Mean Parker score was 3.6 (range: 1-5) preoperatively, and 2.4 (range: 1-5) and 2.7 (range: 1-5) at 24 and 48 weeks, respectively: i.e., not significantly different from preoperative values (p=0.057 and p=0.054, respectively). There were no decubitus-related complications. Two patients (20%) showed other complications, including 1 deep infection requiring material ablation. Consolidation was systematic, without hindfoot malunion. DISCUSSION: Retrograde TIMN appeared to be a useful option for ankle fracture in elderly patients for whom classical internal fixation was contraindicated. It allowed immediate resumption of weight-bearing and early rehabilitation, with no increased morbidity or mortality. LEVEL OF EVIDENCE: IV.

Minimally invasive internal fixation of distal femur fractures.

Fractures of the distal femur remain a daunting challenge. Since 1970, operative treatment has been recommended. Unfortunately, it is fraught with complications, and techniques have been developed to limit incidence of non-union, infection and stiffness. A soft-tissue friendly approach is the key point, with minimally invasive surgery as the ultimate goal: its biological and anatomical advantages have been demonstrated, but clinical studies have been less convincing, being based on historical series. At present, retrograde nailing and minimally invasive percutaneous plate osteosynthesis (ideally by locking plate) are the two main techniques. Unfortunately, reports tend to compare implants rather than operative techniques, hindering solid conclusions. Lastly, the delineation of "distal femur fracture" is quite variable, sometimes situated well above the AO epiphyseal square. Meta-analyses find almost no difference between the two implants in minimally invasive procedures. The main advantage of the plate is its versatility, whereas nailing can be impossible in case of certain hip or knee prostheses, compound articular fracture or medullary canal obstruction by fixation material (nail, stem, screw, etc.). The role of arthroscopy is limited. Only a few case reports describe its use in reduction of epiphyseal fracture. In the last analysis, the surgeon's experience is more relevant to outcome than any particular implant.

Unicondylar fractures of the distal femur.

BACKGROUND: Unicondylar fractures of the distal femur are rare, complex, intra-articular fractures. The objective of this multicentre study was to assess the reduction and fixation of unicondylar fractures. HYPOTHESIS: Anatomic reduction followed by strong fixation allows early rehabilitation therapy and provides good long-term outcomes. MATERIAL AND METHODS: We studied 163 fractures included in two multicentre studies, of which one was retrospective (n=134) and the other prospective (n=29). Follow-up of at least 1 year was required for inclusion. The treatment was at the discretion of the surgeon. Outcome measures were the clinical results assessed using the International Knee Society (IKS) scores and presence after fracture healing of malunion with angulation, an articular surface step-off, and/or tibio-femoral malalignment. RESULTS: Mean age of the study patients was 50.9 ± 24 years, and most patients were males with no previous history of knee disorders. The fracture was due to a high-energy trauma in 51% of cases; 17% of patients had compound fractures and 44% multiple fractures or injuries. The lateral and medial condyles were equally affected. The fracture line was sagittal in 82% of cases and coronal (Hoffa fracture) in 18% of cases. Non-operative treatment was used in 5% of cases and internal fixation in 95% of cases, with either direct screw or buttress-plate fixation for the sagittal fractures and either direct or indirect screw fixation for the coronal fractures. After treatment of the fracture, 15% of patients had articular malunion due to insufficient reduction, with either valgus-varus (10%) or flexion-recurvatum (5%) deformity; and 12% of patients had an articular step-off visible on the antero-posterior or lateral radiograph. Rehabilitation therapy was started immediately in 65% of patients. Time to full weight bearing was 90 days and time to fracture healing 120 days. Complications consisted of disassembly of the construct (2%), avascular necrosis of the condyle (2%), and arthrolysis (5%). The material was removed in 11% of patients. At last follow-up, the IKS knee score was 71 ± 20 and the IKS function score 64 ± 7; flexion range was 106 ± 28° (<90° in 27% of patients); and 12% of patients had knee osteoarthritis. CONCLUSION: Anatomic reduction of unicondylar distal femoral fractures via an appropriate surgical approach, followed by stable internal fixation using either multiple large-diameter screws or a buttress-plate, allows immediate mobilisation, which in turn ensures good long-term outcomes. LEVEL OF EVIDENCE: IV, cohort study.

External fixation of distal femoral fractures in adults' multicentre retrospective study of 43 patients.

BACKGROUND: A multicenter cohort of 43 adults with distal femoral fractures (DFFs) managed with external fixation was evaluated to determine the potential of this treatment. PATIENTS AND METHODS: The patients were young adults (mean age: 39.6 years) with high-energy trauma; 12 had polytrauma and 41 multiple fractures. Most patients (38/43) had compound DFFs. Fracture types were A in 3 patients, B in 3 patients, and C in 37 patients. A tibio-femoral construct was required in 11 patients and a femoro-femoral construct in 32 patients. RESULTS: The normal femoral axis was restored within 5° in the coronal plane in 34 (79%) patients and in the sagittal plane in 22 (51%) patients. Axis restoration within 5° in both planes was achieved in 19 (44.7%) patients. After femoro-femoral external fixation, mean malalignment was 4.2° in the coronal plane and 8.6° in the sagittal plane; corresponding values after tibio-femoral external fixation were 1.3° and 8.6°. In 23 patients (of whom 1 was lost to follow-up), external fixation was intended as the only and definitive treatment; among them, 1 required amputation after a failed revascularization procedure, 10 achieved fracture healing within a mean of 21.2 weeks, 6 required conversion to another technique, and 5 underwent non-conservative procedures (total knee arthroplasty in 3 and arthrodesis in 2). In the remaining 20 patients, conversion to internal fixation was intended initially and performed within a mean of 4.7 weeks; 1 of these patients required amputation for ischemia, 3 did not achieve fracture healing, 12 achieved primary fracture healing, and 4 achieved fracture healing after repeated grafting (n=3) or osteotomy (n=1). At last follow-up (at least 1 year), the mean International Knee Society (IKS) Function Score was 67.3 and an IKS Knee Score of 68.5. Range of active flexion was 85.75° overall, 62.3° in the group with intended definitive external fixation and 101° in the group with intended conversion to internal fixation. Healing without complications was achieved in 10 (43%) in the former group and 12 (60%) in the latter group. CONCLUSION: Our data support provisional external fixation followed by early conversion to internal fixation in patients with extensively compounded DFFs; patients with multiple fractures requiring several surgical procedures; and polytrauma patients awaiting hemodynamic, respiratory, or neurological stabilization. LEVEL OF EVIDENCE: IV, retrospective study.

Locked plating for internal fixation of the adult distal femur: influence of the type of construct and hardware on the clinical and radiological outcomes.

INTRODUCTION: Distal femoral fractures are rare and serious. Along with traditional internal fixation, new, dedicated hardware have appeared (distal nails, locked plating). We report the results of a multicenter prospective study of these fractures treated with locked plating. HYPOTHESIS: The short-term results are satisfactory and related to the type of construct and the hardware used, with better results for elastic assemblies and titanium implants. MATERIALS AND METHODS: From June 2011 to May 2012, 92 patients, mean age 64 years, were included in 12 centres. The fractures were classified as follows: 44 type A, 7 type B, and 41 type C according to the AO classification. Thirteen fractures were open. The plates were uniaxial. The assemblies were elastic in 52 cases, rigid in 26, and unconventional in 14. RESULTS: Seventy-six patients underwent a radiological follow-up at 6 months and 66 patients had a clinical result evaluated at 1 year. The mean range of motion was 100° and the mean IKS score was 122. The bone union rate was 87% within 12 weeks. Seven valgus, two varus, ten flexion deformities, and three recurvatum greater than 5° were observed (19.5%). Revisions involved two cases with loss of fixation, five cases of infection, and one case of arthrofibrosis (requiring arthroscopic arthrolysis). Secondary bone grafting was carried out in seven cases (four successfully). No influence of the type of assembly or the hardware used was demonstrated. DISCUSSION: The results remain modest, underscoring the severity of these fractures. Neither the type of construct nor the hardware used influenced the radiological and clinical outcomes. The hypothesis was not confirmed. LEVEL OF EVIDENCE: Level IV prospective, non-comparative study.

Epidemiology of distal femur fractures in France in 2011-12.

INTRODUCTION: Epidemiological study of femoral fractures has been dominated by proximal fractures. Distal fracture requires equal attention for correct management. PATIENTS AND METHODS: A prospective study in 12 French hospital centres between June 1st, 2011 and May 31st, 2012 recruited cases of non-pathologic distal femoral fracture in patients over 15 years of age without ipsilateral knee prosthesis. RESULTS: There were 183 fractures in 177 patients. Mean age was 63.5 years. Female patients (60.5%) were significantly older than males (mean age, respectively 73 versus 48.4 years). Walking was unrestricted in only 83 patients (46.89%). On the AO/OTA (Orthopaedic Trauma Association) classification, there were 86 type A fractures (47%), 29 type B (15.8%) and 68 type C (37.2%). Fractures were open in 32 cases (17.5%), most frequently in male, young patients and type C fracture. Causal trauma was low-energy (fall from own height) in 108 cases, most frequently in female patients and type A fracture. Forty-five patients were proximal femoral implant bearers. CONCLUSION: Distal femoral fracture shows highly variable epidemiology. AO/OTA type A fracture mainly involves elderly, relatively dependent female subjects. Outcome study requires radiographic data and assessment of functional capacity. LEVEL OF EVIDENCE IV: Prospective cohort study.

Blade-plate fixation for distal femoral fractures: a case-control study.

BACKGROUND: The blade-plate is the earliest of the contemporary internal fixation devices introduced for distal femoral fractures. The recent development of dedicated, fixation devices has considerably limited its use. The objective of this study was to evaluate outcomes after blade-plate fixation and after fixation using other devices. HYPOTHESIS: Outcomes after blade-plate fixation are similar to those after condylar screw-plate, distal femoral nail, or locking condylar plate fixation. MATERIAL AND METHODS: We reviewed outcomes after 62 patients managed with blade-plate fixation and included in a multicentre retrospective study (n=57) or a multicentre prospective study (n=5) and we compared them to outcomes after fixation using condylar screw-plates (n=82), distal femoral nail (n=219), or locking condylar plates (n=301). The four groups were comparable for age, gender distribution, occupational status, prevalence of skin wounds, patient-related factors, type of accident, and type of fracture. The evaluation relied on the clinical International Knee Society (IKS) score and on radiographs. RESULTS: No significant differences existed across the four groups for operative time, blood transfusion use, complications, need for bone grafting, non-union rate, or IKS score values. The early surgical revision rate for removal of the fixation material was 4% with the blade-plate and 16% with the other three fixation devices (P=0.02). Post-operative fracture deformity was similar in the four groups with, however, a higher proportion of residual malalignment in the screw-fixation group. The final anatomic axis was 3.3±1.4° with the blade-plate versus 2.3±3.7° with the other three fixation devices. The blade-plate group had few patients with axial malalignment, and the degree of malalignment was limited to 3° of varus and 10° of valgus at the most, compared to 10° and 18° respectively, with the other three fixation devices. CONCLUSION: Despite the now extremely limited use and teaching of blade-plate fixation, as well as the undeniable technical challenges raised by the implantation of this device, the blade-plate is a simple, strong, and inexpensive fixation method. It remains reliable for the fixation of distal femoral fractures. The disfavour into which the blade-plate is currently falling is not warranted. LEVEL OF EVIDENCE: III, case-control study.

Isolated anterior unilateral sacroiliac dislocation without pubic arch disjunction.

Sacroiliac joint dislocations frequently occur in a context of high-energy polytrauma. When there is disruption of the pelvic ring, sacroiliac joint displacements are more often posterior and combine two lesions: either lesions of the pubic arch as well as the posterior arch or bilateral lesions. The case we report here lacks these two characteristics. This is an isolated unilateral sacroiliac dislocation with no opening lesion of the pubic symphysis or fracture of ilio- or ischiopubic rami and with anterosuperior displacement. After emergency reduction of the dislocation, the secondary fixation was not performed, due to initial hemodynamic instability compounded by deteriorating central nervous system condition.

Primary total knee arthroplasty in the management of epiphyseal fracture around the knee.

INTRODUCTION: Over the past few years the use of arthroplasty was broadened to treating complex epiphyseal fractures at the shoulder and elbow joints. Similar trends to treat this type of fractures at the knee are less documented. Based on a multicenter retrospective series study, the aims of this work is to evaluate the short term clinical results of total knee prostheses in the management of comminuted epiphyseal fractures around the knee, to identify the technical issues and fine tune the indications. MATERIAL AND METHODS: Following the initiative of the French Hip and Knee Society (SFHG) and the Traumatology Study Group (GETRAUM), 26 charts from eight different centers in France were included in this multicenter retrospective series. Inclusion criteria were: primary total knee arthroplasty (TKA) in the management of complex articular fractures involving the proximal end of the tibia or distal end of the femur. Surgical features were identified and complications were analyzed. The assessment protocol at last follow-up was standardized and included patient demographic data, analysis of the Parker and IKS scores. RESULTS: During the immediate postoperative period, six patients (23%) reported a general complication and four patients (15%) a local arthroplasty-related complication. At last follow-up (mean 16.2 months), the overall final Parker score was 6.3 (a mean decrease of 1.7) and the mean IKS knee score was 82 points for a mean function score of 54 points. DISCUSSION: Primary TKA is a suitable management option for complex fractures in autonomous elderly patients suffering from knee osteoarthritis. The key technical details of this procedure should be respected and meticulously planned to achieve optimal results and limit the risk of complications. This risk in these acute complex fractures remains higher than after conventional TKA but comparable to that observed after TKA for post-traumatic arthritis. LEVEL OF EVIDENCE: IV; retrospective cohort study.

The concept of locking plates.

After a short historical review of locking bone plates since their inception more than a century ago to the success of the concept less than 15 years ago with today's plates, the authors present the main locking mechanisms in use. In the two broad categories - plates with fixed angulation and those with variable angulation - the screw head is locked in the plate with a locknut by screwing in a threaded chamber on the plate or by screwing through an adapted ring. The authors then provide a concrete explanation, based on simple mechanical models, of the fundamental differences between conventional bone plates and locking plates and why a locking screw system presents greater resistance at disassembly, detailing the role played by the position and number of screws. The advantages of epiphyseal fixation are then discussed, including in cases of mediocre-quality bone. For teaching purposes, the authors also present assembly with an apple fixed with five locking screws withstanding a 47-kg axial load with no resulting disassembly. The principles of plate placement are detailed for both the epiphysis and diaphysis, including the number and position of screws and respect of the soft tissues, with the greatest success assured by the minimally invasive and even percutaneous techniques. The authors then present the advantages of locking plates in fixation of periprosthetic fractures where conventional osteosynthesis often encounters limited success. Based on simplified theoretical cases, the economic impact in France of this type of implant is discussed, showing that on average it accounts for less than 10% of the overall cost of this pathology to society. Finally, the possible problems of material ablation are discussed as well as the means to remediate these problems.

Zyxin is up-regulated during megakaryocytic differentiation of human UT-7/c-mpl cells.

To characterize genes involved in megakaryocytic commitment, we compared expression profiles of bipotent cells (UT-7/c-mpl) with those of the same cells induced to differentiate towards megakaryopoiesis in the presence of TPO. Using cDNA arrays, we showed that 12 out of 2260 genes changed their expression level after 6h of TPO stimulation. One of these genes encodes for zyxin, a cytoskeleton protein component. Zyxin is up-regulated at the mRNA and protein levels in UT-7/c-mpl cells in response to TPO confirming the reliability of the cDNA array technology. Similarly, when CD34 positive cells were induced to differentiate into megakaryocytes, zyxin mRNA was accumulated. Furthermore, when megakaryocytes were allowed to spread on fibrinogen, formation of stress fibers and lamellipodia was induced and zyxin was localized at the picks of actin stress fibers. These results suggest an important role for zyxin during megakaryocytic differentiation and more precisely in the regulation of the integrin mediated adhesion process in megakaryocytes.

[Factors affecting quality of care for elderly subjects undergoing surgery for hip fracture: review of the literature]. / Facteurs de qualité de la prise en charge des sujets âgés opérés d'une fracture de l'extrémité supérieure du fémur: revue de la littérature.

Hip fractures are one of the leading causes for admission of elderly subjects to healthcare facilities. Because of population aging, the incidence of hip fractures has increased considerably over the last years and will continue to increase in industrialized countries. Hip fracture in an elderly subject may be life threatening and has a significant functional and social impact not only because of the fracture itself, but also because of the risk of complications related to the patient's health status and the long hospital stay. The purpose of this work was to identify in the published literature professional practices, excepting the surgical procedure, associated with better early and long-term outcome in elderly patients with hip fracture. Questions raised concerning the patient's hospital stay include factors related to the preoperative phase (time to surgery, usefulness of traction), the operation itself (antibiotic prophylaxis, anesthesia technique), and the postoperative phase (prevention of venous thrombosis, malnutrition, episodes of confusion, duration of indwelling bladder catheter, correction of anemia, geriatric care during the stay in the orthopedic ward, early and intense rehabilitation, prevention of recurrence). Among these factors, several appear to be associated with better outcome, including long-term outcome--surgery as early as possible in light of the patient's general status, antibiotic prophylaxis in accordance with standard recommendations (SFAR), prevention of venous thrombosis with low-molecular-weight heparin initiated at admission and associated with elastic contention. Oral nutritional support is probably beneficial and should be proposed for all patients. Particular attention must be given to prevention of confusion in order to reduce the rate of institutionalization. The rythm of rehabilitation exercises should be at least five sessions per week. Finally, there are several methods, which are effective in preventing recurrence, taking into account osteoporosis, risk of falls. Preventive measures should be instituted for all patients undergoing surgery for hip fracture.

Exclusion of muscle specific actinin-associated LIM protein (ALP) gene from 4q35 facioscapulohumeral muscular dystrophy (FSHD) candidate genes.

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disorder for which no candidate gene has yet been identified. The gene corresponding to one of the novel human cDNAs that we cloned on the basis of a muscle restricted expression pattern [Piétu G, Alibert O, Guichard B, et al. Genome Res 1996;6:492-503] was mapped in the region of the FSHD1A genetic locus, i.e. one of the loci involved in this muscular dystrophy. The corresponding encoded protein contains a PDZ and a LIM domain, two protein-protein interaction domains, and was very recently shown to bind alpha-actinin-2 and was named ALP (actinin-associated LIM protein) [Xia H, Winokur S, Kuo W, Altherr M, Bredt D. J Cell Biol 1997;139:507-515]. We raised a specific polyclonal anti-ALP serum against an ALP recombinant polypeptide to evaluate the size, level of expression and subcellular localization of ALP in three patients, clearly diagnosed with FSHD disease. Quantitative or qualitative alterations of ALP expression have not been detected in any of them, thus prompting us to exclude ALP as a FSHD gene candidate.

[Anterior instability of the shoulder in athletes: apropos of 51 cases of stabilization using the Latarjet-Patte intervention]. / Instabilité antérieure de l'épaule chez le sportif: à propos de 51 cas de stabilisation par intervention de Latarjet-Patte.

We report the 45-month results of the Bristow Latarjet procedure in 48 patients (51 shoulders), all sportsmen. At review, 87% were satisfied, 71% practiced the same sport at the same level, and 74% had good or excellent objective results. Five patients reported recurrence of dislocation, external rotation was restricted more than 10 degrees in 36%, and 31% of the shoulders had radiological evidence of degenerative arthropathy. We compare the results with the literature, particularly concerning recurrent dislocation and osteoarthritis.

Characterization of recombinant von Willebrand factors mutated on cysteine 509 or 695.

The interacting domain of vWF with platelet GPIb has been shown to overlap the large A1 loop formed by the intra-chain disulfide bond linking Cys 509 to Cys 695. In order to further investigate the role of the conformation of this region, we have expressed in COS-7 cells three mutated full-length recombinant vWFs (rvWFs) in which the substitutions Cys509Gly, Cys509Arg or Cys695Gly have been introduced by site-directed mutagenesis. SDS-agarose gel electrophoresis demonstrated an impaired multimerization of the mutants with undetectable high molecular weight multimers and a decrease of the relative amounts of the intermediate sized multimers. Binding analysis showed that rvWFC509G and rvWFC509R did not interact with botrocetin but spontaneously interacted with GPIb; the latter binding remained unchanged in the presence of ristocetin. This indicates that the substitution of Cys509 by Gly or Arg creates a conformation of vWF that increases its binding to GPIb. In contrast, rvWFC695G which did not react with botrocetin was also unable to interact with GPIb even in the presence of ristocetin, indicating that sequences interacting with GPIb are masked and/or disrupted. In conclusion, the substitution of each of the Cys509 and 695 results in mutant proteins which may be "locked" into active or inactive conformations in regard to the binding to platelet GPIb receptor.

[The Seidel humeral nail in limited indications: pathological fractures, delayed union, pseudarthrosis and reconstruction]. / Le clou huméral de Seidel dans les indications limites: fractures pathologiques, retards de consolidation, pseudarthroses et reconstructions.

The authors report 10 cases of Seidel locked intramedullary nailing of the humeral shaft for borderline indications (5 delayed unions, 2 complex nonunions, 2 reconstructions for tumor and a panmetastatic humerus). All delayed unions went to union in spite of unscrewing of the expanding screw in 2 cases. In cases of segmental reconstruction, union never occurred due to unlocking of the distal bolt by bone incompetence. Diaphyseal straightening was obtained, but not rotational stability. These elderly patients, in whom the osteoporotic bone is inadequate for plate osteosynthesis, were pleased with the result in comparison with their preoperative status. For pathological fracture, a painfree status is obtained. No subacromial impingement was observed.

[Osteosynthesis by plate in fractures of the distal end of the radius]. / Les ostéosynthèses par plaque des fractures de l'extrémité inférieure du radius.

The authors recall the place of apposed plate fixation of fractures of the lower end of the radius, most of which are anterior. The ideal indication is the simple fracture by articular or supra-articular, compression-flexion. The importance of modelling and positioning of the plate is emphasised. The use of other types of fixation for composite systems is possible in complex fractures. Anatomical reconstruction must be obtained to ensure a satisfactory functional result.

Defects in type IIA von Willebrand disease: a cysteine 509 to arginine substitution in the mature von Willebrand factor disrupts a disulphide loop involved in the interaction with platelet glycoprotein Ib-IX.

Type IIA von Willebrand disease (vWD) is characterized by the loss of high and intermediate weight multimers of von Willebrand factor (vWF) from plasma. The 3' end of exon 28 in the vWF gene from four type IIA vWD patients was amplified by the polymerase chain reaction, cloned and sequenced. Sequencing identified two potential missense mutations resulting in the amino acid substitutions Arg 834-->Gln and Glu 875-->Lys in the mature vWF subunit within an area of vWF where mutations in type IIA vWD have been reported. Neither of these amino acid substitutions was found in over 100 normal alleles tested by allele specific oligonucleotide hybridization. A polymorphism (Val 802-->Leu) was identified in another patient. Other areas of exon 28 were analysed by denaturing gradient gel electrophoresis (DGGE) and DNA from one patient demonstrated an irregular DGGE pattern on the 5' end of the exon. Sequencing demonstrated an amino acid substitution of an arginine for cysteine at position 509 adjacent to an area of vWF where defects associated with type IIB vWD have been found. This substitution was not found in 100 normal chromosomes tested by restriction enzyme digestion. The Cys 509-->Arg substitution eliminates an intramolecular disulphide bridge formed by Cys 509 and Cys 695 which is important to maintain the configuration of vWF functional domains that interact with platelet glycoprotein Ib-IX.

[Fracture of the femoral neck complicating algodystrophy of the hip during pregnancy. Apropos of 2 cases]. / Fracture du col du fémur compliquant une algodystrophie de hance au cours de la grossesse. A propos de 2 observations.

The authors report 2 cases of fracture of the femoral neck in pregnant women. This is a serious complication of a poorly understood disease, algodystrophy of the hip during pregnancy (transient osteoporosis of the hip of pregnancy, as referred by Anglo-saxon practitioners), whose main clinical, paraclinical and course characteristics are reported. The risk of subcapital fracture is maximal during the period of term, justifying recumbency in painful forms. In spite of the phantom appearance of the femoral head and neck, this type of fractures should not be confused with tumoral osteolysis, since they always unite within usual intervals.