[Intramedullary pinning of diaphyseal fractures of both forearm bones in adults: 46 cases]. / Embrochage centromédullaire des fractures diaphysaires des deux os de l'avant-bras chez l'adulte.

PURPOSE OF THE STUDY: The goal when treating shaft fractures of the forearm bones is to obtain good bone healing with good preservation of upper limb function. We report a retrospective (1995-2004) consecutive series of patients aged 32 years on average (range 16 to 92 years) who presented 46 shaft fractures of both forearm bones. MATERIAL AND METHODS: Using Hackethal's classification by sixths, the fracture involved the 3rd and 4th sixth in 39 cases (84.7%) for the radius and 33 (71.7%) for the ulna. Seventeen (37%) patients were trauma victims with multiple injuries. Fourteen fractures (30.4%) were open and all fractures were treated: 11 stage I (23.9%), two stage II (4.3%) and one stage III (2.3%). Intramedullary pinning was used in all cases for the radius and the ulna. In 27 patients (58.6%) pinning was achieved without open access to the focus. Pin diameter was 2.5mm for 38 cases (82.6%). Self-controlled rehabilitation exercises were started immediately without complementary immobilization. Outcome was assessed in 41 patients with a mean follow-up of 18 months (range three months to seven years). RESULTS: Functional outcome, according to Tscherne and Oestern, was very good or good in 31 cases (75.5%). For 35 cases (85.4%) bone healing was achieved at mean 3.5 months for the radius and four months for the ulna. Retarded healing was noted in four cases (9.7%) for the ulna. For the 41 patients reviewed, 11 (26.8%) presented axial misalignment of one of the forearm bones with an angle strictly greater than 10 degrees for three. There were six patients with nonunion (14.6%), of both bones in two and one in four. Radioulnar synostosis was observed in four cases (9.7%). No infections or recurrent fractures were noted. DISCUSSION: The localization of the fracture line affected the outcome. Among the four cases with a fracture in the 5th sixth of the radius, two developed misalignment with an angle strictly greater than 10 degrees and one presented a secondary displacement which required revision on day 15 for plate-screw fixation of the radius. This might be due to the spreading corticals of the distal radius where pin stabilization would be less effective than for fractures in the 3rd or 4th sixths where the corticals run parallel. Outcome was less satisfactory when the fracture focus was opened. Four of the six nonunions and three of the four synostoses occurred among the 19 patients who had open pinning. This might be due to loss of the fracture hematoma. Analysis of the type of fixation has shown that our best results were obtained when we used a single 2.5 mm elastic pin. For the cases where we used a smaller pin (2 mm), we had three major misaligments, one nonunion involving both bones and one recurrent dislocation of the radial head. There were no infections or recurrent fractures in this series where the pin was removed in 27 patients (65.6%) at mean one year. CONCLUSION: Intramedullary pinning is an attractive alternative for the treatment of shaft fractures involving both forearm bones in adults. Best results are obtained if the fracture (situated outside the 5th sixth) can be stabilized without opening the focus with a single 2.5 mm pin. This method combines the advantages of closed osteosynthesis, that is, a simple nontraumatic procedure decreasing the risk of suppuration, and early return of function, limiting postoperative immobilization. It enables early sturdy bone healing with a low risk of recurrent fracture.

[Screw fracture after sliding hip screw fixation of an intertrochanteric fracture]. / Fracture de la vis cervicale d'une vis-plaque à glissement. A propos d'un cas à 1, 5 an de recul.

Although no cases have been reported to date, fracture of a sliding hip screw on a screw-plate fixation is a real entity since material watch registries have revealed two non-published cases. We report an illustrative case. A 67-year-old man was hospitalized for a right intertrochanteric fracture. The patient was treated with a sliding hip screw plate fixation (short cannon, 105 mm screw). On the eighth postoperative day, fracture impaction was present with complete loss of impaction reserve associated with secondary discrete divergence in the cannon-screw alignment. Weight-bearing was postponed until the 45th postoperative day. At three months, bone healing had not been achieved. A clear image was also visible at the plate end of the cannon. The patient complained of persistent pain but there were no signs of infection. At the fifth month, the patient fell from the standing position and standard x-rays visualized the nonunion of the intertrochanteric fracture plus a infratrochanteric diaphyseal fracture line in addition to a fracture of the sliding hip screw. The plate screws were intact. The patient underwent revision osteosynthesis with a Medoff plate. Fracture of a sliding hip screw is a rare event. In the present case, the mechanism involved an insufficient impaction reserve and use of a short cannon. Treatment requires extraction of the distal fragment of the screw and a new cemented osteosynthesis.

[Radiographic diagnosis of dislocated inverted shoulder prosthesis: two cases of unrecognized dislocation]. / Diagnostic radiologique des luxations de prothèse d'épaule inversée: à propos de 2 luxations passées inaperçues.

Dislocation of inverted shoulder prostheses are rarely described in the literature. Diagnosis is relatively difficult as illustrated by two cases reported here which went unrecognized. The problem is the absence of any clear clinical sign of dislocation and the rather difficult interpretation of the radiographic images. We propose a method for analyzing the radiographic images which can be used to confirm the absence of dislocation on the AP view.

[Intra- and postoperative fractures of the femur in total knee arthroplasty: risk factors in 32 cases]. / Facteurs du risque de fracture du fémur distal dans les protheses totales du genou: Etude de 32 fractures per et postopératoires.

PURPOSE OF THE STUDY: We reviewed fractures of the distal femur occurring during or after total knee arthroplasty in order to identify risk factors. MATERIAL AND METHODS: Twelve intraoperative fractures occurred between 1990 and 2000 among 617 total knee arthroplasties performed during this period. The circumstances of these fractures were noted in comparison with other prosthetic implants. Twenty other fractures of the distal femur occurred in 20 patients who had had a total knee arthroplasty during the same time period. Mean patient age at surgery was 72 years (range 69-77). In addition to demographic data, we noted risk factors: bone demineralization related to general condition, rheumatoid arthritis or corticosteroid therapy, trochlear notch prior to the trochlear cut, bone resorption under the femoral implant, repeated knee surgery, abnormal stress on the distal femur due to hip disease, periprosthetic osteolysis without loosening related to polyethylene debris or metallosis, loosening, type of prosthesis, loss of bone stock because of the femoral implant, life of prosthesis. RESULTS: Intraoperative fractures usually occurred in specific circumstances: use of a posterior stabilized prosthesis, probably with insufficient preparation and position of the stabilization element, probably excessive impaction in osteoporotic bone (rheumatoid arthritis), difficult exposure (arthroplasty after prior osteotomy), fracture starting from the separator passing over the posterior aspect of the tibia and reaching the intercondylar notch. Independently of these intercondylar fractures, supracondylar or diaphyseal fractures were essentially observed for revision prostheses using a femoral stem. Postoperative fractures were observed in patients who had prior surgery of the distal femur (revision of femoral osteotomy, fracture of the distal femur, arthrodesis), in patients with significant loss of bone stock (posterior stabilized prosthesis), or poor bone quality (rheumatoid arthritis), and in elderly patients with neurological impairment and frequent falls. The trochlear notch did not appear to be sufficient to be the only cause of fracture but was nevertheless an element frequently associated with other risk factors. DISCUSSION AND CONCLUSION: This study shows that fracture of the distal femur occurs in certain preferential circumstances. Considering these elements, a certain number of preventive measures can be discussed for technical modifications or choice of implants.