Loosening of the femoral component after use of the medullary-plug cementing technique. Follow-up note with a minimum five-year follow-up.

Of the 171 total hip replacements reported on previously that had had a minimum length of follow-up of two years, 117 replacements in 104 patients were analyzed at a minimum of five years postoperatively (average, seventy-four months; range, sixty to ninety-four months) to assess the rate of loosening of the femoral component. At the time of cementing of the femoral component, the medullary canal had been plugged with a bolus of bone cement and then filled with doughy Simplex-P methylmethacrylate in a retrograde fashion using a cement gun. The femoral components, made of a chromium-cobalt alloy, had a rectangular cross-sectional shape to the stem and a medial collar. Three categories of loosening were used: definite (requiring radiographic evidence of migration of the component or the cement), probable (requiring evidence of a complete radiolucent zone at the bone-cement interface on one radiograph or more), and possible (a radiolucent zone at the cement-bone interface of more than 49 per cent but less than 100 per cent on one radiograph or more). One femoral component had been removed for aseptic loosening at another hospital, leaving the patient with a resection arthroplasty. One other (1.7 per cent) was definitely loose. No femoral component was categorized as probably loose, and only two were possibly loose.