The results of 111 Charnley and Charnley-Müller total hip replacements were reevaluated a minimum of ten years postoperatively. Data was available on 65 cases, 46 of which were by personal examination and 19 by questionnaire.
Twenty cases required revision surgery. Reasons for this were, the loosening of the femoral component in ten cases, loosening of both the femoral and acetabular component in four, recurrent dislocaction in one, and fracture of the femoral shaft in three. There was a significantly higher incidence of revislon suragery in patients who had a Charnley-Müller prosthesis and who were younger than sixty years of age.
Roentgenographic loosening of the femoral component was recognized in all revised hips. In non-revised hips, loosening of the femoral component was seen in 39.3%, while loosening of the acetabular component was only 14.3%. Valgus, more than 50 degrees, of the socket and poor packing of cement of the femoral component significantly influenced the incidence of loosening, whereas body weight and status of the contralateral hip were not shown to influence loosening.
Since loosening of the femoral component seems unavoidable with revision surgery necessary in sone patients, we advocate using a cementless prosthesis to preserve bone stock allowing revision to be performed without difficulty.
