The Effect of Positive Medial Cortical Support in Reduction of Pertrochanteric Fractures with Posteromedial Wall Defect Using a Dynamic Hip Screw

BACKGROUND: We evaluated the radiological and clinical results of reduction using a dynamic hip screw according to the grade of medial cortical support in patients with AO Foundation and Orthopaedic Trauma Association (AO/OTA) classification type 31-A2 pertrochanteric fractures. METHODS: We enrolled 100 patients with AO/OTA type 31-A2 fractures with displaced lesser trochanter fragments (length of the cortical area longer than 20 mm on the pelvis anteroposterior view). Patients with positive medial cortical support were assigned to group 1 (n = 28); neutral medial cortical support, group 2 (n = 42); and negative medial cortical support, group 3 (n = 30). Radiological evaluation was done by measuring the change in the femoral neck-shaft angle and sliding distance of the lag screw. Clinical outcomes of each group were compared by means of the walking ability score proposed by Ceder. RESULTS: Group 1 showed significantly less changes in the femoral neck-shaft angle and shorter sliding distance than groups 2 and 3. Group 2 showed significantly less changes in the femoral neck-shaft angle and shorter sliding distance than group 3. Group 1 showed significantly higher walking ability scores than group 3 (p = 0.00). The use of trochanter stabilizing plates or fixation using wires for posteromedial wall defect resulted in no significant changes in terms of the femoral neck-shaft angle or sliding distance. CONCLUSIONS: In the treatment of pertrochanteric fractures accompanied by posteromedial wall defect using a dynamic hip screw, reduction with negative cortical support should be avoided.

Femoral Head Size of 36 mm against Highly Cross-linked Polyethylene in Patients Younger than 60 Years: Minimun Three Years of Follow Up / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate the early results of total hip arthroplasty (THA) performed using large diameter femoral head against with highly cross-linked polyethylene as a bearing surface in patients less than sixty years of age. MATERIALS AND METHODS: Seventy patients were enrolled and retrospectively reviewed. The mean age of patients at index surgery was 49 years and the mean follow-up period was 61 months. Clinical follow-up involved implementing the Harris hip score (HHS) and a radiographic evaluation that included linear radiolucency, osteolysis, and loosening. An annual wear rate was performed at 6 weeks; at 3, 6, and 12 months; and on a yearly basis thereafter. RESULTS: The average HHS at last follow-up was 94 (range: 82-98). Radiographically, no osteolysis in the pelvis or proximal femur was observed in any patient. No acetabular cup or femoral stem failed due to aseptic loosening. No eccentric wear was observed on any liner, and no liner fracture occurred. However, one patient experienced hip dislocation. The average femoral head penetration rate during the first postoperative year was 0.077+/-0.026 mm/year, and the average steady-state wear rate was 0.033+/-0.023 mm/year. CONCLUSION: THA with a large diameter femoral head of highly cross-linked polyethylene in patients younger than 60 years of age was found to produce results comparable to previous in vitro laboratory hip simulation studies. In particular, patient satisfaction was high due to no limitation in range of motion or hip posture during the early post-operative period. Longer-term follow-up is required to demonstrate the clinical benefits of this new material more comprehensively.