Association of intra-operative metaphyseal fractures with prosthesis size during hemiarthroplasty of the hip.

PURPOSE: To study the possible causes of intra-operative metaphyseal fractures in elderly patients undergoing hemiarthroplasty for displaced intracapsular femoral neck fracture. METHODS: 36 men and 228 women aged 61 to 89 years with 273 displaced femoral neck fractures underwent hemiarthroplasty using a hydroxyapatite ceramic-coated Furlong bipolar prosthesis. Anteroposterior and lateral radiographs were taken immediately after surgery to evaluate the presence and type of any intra-operative fractures (classified according to the Vancouver system) and their effect on stem stability or osseointegration. Pain and clinical outcomes were evaluated using a visual analogue scale and the Harris Hip Score. RESULTS: Regarding the 273 surgeries for displaced femoral neck fracture, 28 (10%) were associated with intra-operative metaphyseal fracture (21 Vancouver type AL and 7 type AG). There was a correlation between intra-operative metaphyseal fractures and stem size. A size-9 stem was used in 64 surgeries without any fracture. A size-10 stem was used in 129 surgeries in which 11 (9%) sustained fractures, and a size-12 stem was used in 80 surgeries in which 17 (21%) sustained fractures. Postoperatively, 25 cases developed hip-related problems (thigh pain=14 and periprosthetic fractures=8) after 3 to 18 months. No patient whose metaphyseal fracture was fixed had hip problems. CONCLUSION: In elderly women with compromised bone quality, extra care is needed to achieve better fitting so as to avoid iatrogenic metaphyseal fractures. Under-sizing or cementing of the prosthesis is recommended when encountering difficulties.

Quadriceps pull test: an outcome predictor for lateral retinacular release in recurrent patellar dislocation.

Recurrent dislocation of the patella is a disorder with a complex aetiology. Several surgical procedures have been recommended for its correction, but there are few clinical or radiological guidelines to facilitate the selection of a particular procedure. The results of treating a series of 29 knees are presented with a follow-up of at least 2 years. A significant correlation has been found between the horizontal movement of the centre of the patella on quadriceps contraction (quadriceps pull test) and surgical outcome when lateral release alone is selected for the correction of recurrent patellar dislocation.

Complex carpal dislocation.

We present an unusual case of carpal dislocation which to our knowledge has not previously been described in any of the current classifications of such injuries. Despite the extensive damage sustained, the case was managed without difficulty and outcome has been very satisfactory.

Comparative evaluation of the two positions used for imaging of trochanteric fractures.

This study evaluates and compares the efficacy of the two positions used for imaging of the hip in trochanteric fractures. One hundred patients with grade I or grade II trochanteric fractures were divided into two equal groups. In group I the fracture was reduced and the opposite hip was brought to full abduction, neutral flexion and neutral rotation. In group II, the fracture was reduced and the opposite hip was flexed beyond 90 degrees, abducted and externally rotated. Only patients with minimal or no comminution were included in this study. The radiation exposure time was considerably less in group II. The abduction angle between the two limbs of the fracture table was higher in group II and it was possible to visualize the femoral head completely in the lateral view in 96 per cent of patients in group II and 76 per cent in group I. We strongly recommend that the opposite hip should be flexed to about 90 degrees, abducted and externally rotated if it is not possible to see the femoral head completely in the lateral view.

Dynamic assessment of anterior cruciate ligament using an electronic force plate.

The active force exerted by the movement of arms and trunk with the knee in extension was measured in 25 patients with anterior cruciate ligament deficient knee. The electronic force sensitive foot plate was used to measure the force. Two sets of measurements were carried out. The antero-posterior stress test for measurement of Fy and the rotational stress test for measurement of Mz. Peak values obtained in anterior cruciate deficient knee were compared with the normal knee on the other side. The measurement of the difference in Fy was found to be a reliable indicator of instability of the knee, but no significant difference was found in the peak torque values (Mz) between the two knees. This study suggests that this test may be useful in the objective measurement of knee instability. Details of the method used and its possible indications are discussed.