Using modular fluted tapered stem for management of periprosthetic femoral fracture in revision hip arthroplasty / 中华骨科杂志

ABSTRACT

Objective To evaluate the technique and clinical results of the modular fluted tapered stems for treating periprosthetic femoral fractures in revision hip arthroplasty.Methods From August 2007 to February 2014,fourteen patients (14hips) with periprosthetic femoral fractures underwent revision hip arthroplasty with modular fluted tapered stem.A retrospective analysis was performed involving all patients who were followed-up more than 2 years.The subjects consisted of 4 males and 10 females with mean age of 73.4±6.6 years (range,62-82 years) at the time of revision.All patients were unilateral with 8 left hips and 6 right hips.The status of primary arthroplasty was bipolar hemiarthroplasty in 3 patients and total hip arthroplasty in 11 patients.Nine cases were with cemented stems,5 cases with uncemented stems.The interval from primary hip arthroplasty to revision surgery ranged from 40 to 163 months,with an average of 120.9±31.9 months.Eight cases with Vancouver type B3 periprosthetic femoral fracture were found preoperatively,6 cases with aseptic loosening and bone deficiency occurred periprosthetic femoral fracture during the operation.Based on the Paprosky classification system for femoral bone deficiencytype ⅢA in 8 hips,type ⅢB in 5 hips,type Ⅳ in 1 hip.Both the femoral and the acetabular components were revised in 9 patients.All femoral fractures were treated with cable fixation,and the cortical allograft struts were used to augment femoral bone stock in 7 patients.The patients were followed up at 6 weeks,3 months,6 months,9 months,12 months and annually thereafter.Harris Hip Score System and radiographic examination was used to evaluate the clinical results,including fracture union,implant stability,bone stock,hip joint function and postoperative complications.Results The mean duration of follow-up was 62.1 ±22.2 months (range,30-96 months).The mean times of fracture union were 6.2±2.5 months (range,3-12 months).The Harris Hip Score improved from 29.6± 10.3 preoperatively to 86.3±4.2 postoperatively (t=-21.6,P=0.00).Thirteen cases (93％,13/14) had the stem subsidence of 4.9±2.5 mm (range,0-9 mm).Thirteen cases (93％,13/14) were presented with femoral bony restoration.Two cases showed incorporation of the allograft in 7 patients.One patient developed deep venous thrombosis of lower limbs,and one suffered from subcutaneous hematomas after surgery.There was no infection,aseptic loosening,dislocation or periprosthetic fracture complications at the followup.Conclusion The short-medium term results of the modular fluted tapered prosthesis applied in periprosthetic femoral fractures are encouraging in revision hip arthroplasty.The present technology can provide reliable primary stability and can tolerate minimal subsidence postoperatively.