Predictors affecting the results of impaction grafting for revision hip surgery

ABSTRACT

Twenty eight consecutive hips in 28 patients were evaluated at an average 47 months [range 30-75 months] after revision hip surgery reconstructed with impaction grafting. The principle revision procedure was the first revision in 20 hips [71.4%], the second revision in 4 [14.3%] hips, and the third revision in 4 hips. A collarless double tapered polished stem [CPT; Zimmer, Warsaw, Indiana] was used in 24 femora [85.8%]. Harris hip score was used to evaluate the function of the hip postoperatively. Implant migration was measured using Oswestry Roentgen Monophotogrammetric analysis software [ORMA]. By the time offollowup three hips [10.7%] had been re-revised. Two hips because of periprosthetic fracture femur and one because of recurrent dislocations. On the femora side significant correlations were found between stem tilt and two predictors the number of previous revisions [p = 0.03] and the degree of femoral bone loss [P = 0.04]. Significant correlation was found between post operative pain and three predictors vertical cup migration [p = 0.05], graft incorporation [p = 0.05] and the degree of pre-operative acetabular bone deficiency. [p = 0.024]. This study shows durable results using impaction grafting and identified the degree of bone loss, number of re-revision, and cup migration as important predictors in impaction grafting