Distal femoral cortical hypertrophy: predisposing factors and their effect on clinical outcome

The clinical and radiographic features of 109 hybrid total hip replacements performed between 1986 and 1992 in 96 consecutive patients were retrospectively reviewed. A cementless Harris-Galante (HGP1) cup and a 32 mm monobloc straight Muller stem were used in all cases. The overall prevalence of distal femoral cortical hypertrophy (DCH) was 43.1%. Male sex, underlying diagnosis of avascular necrosis and Charnley grade A were among the factors that predisposed to the development of DCH. The prevalence of stem radiolucencies was lower in the group of patients who developed DCH compared with those without hypertrophy. The Harris Hip Score ranged between 5 and 54 preoperatively and the average HHS was more than 80 postoperatively. No association was found between DCH and thigh pain.