Radiographic Evaluation of the “Conus” Uncemented Stem

Abstract

The purpose of this study was to evaluate 54 “Conus” uncemented stems both clinically and radiologically. The radiological evaluation was carried out to verify the stability of this rounded cross-section stem in terms of bone ingrowth and axial subsidence. Clinically, 39 hips (72%) were rated excellent, 13 (24%) were rated good, 2 (4%) were rated fair or poor. The average Harris Hip Score increased from 53 before operation to 93 at the time of the last follow-up (average FU 22.5 months). None was reoperated. Radiologically, 13 stems (24%) were judged to have subsided using a method described by Loudon and Charnley (6). Calcar modification, observed in 22 hips (41%), consisted of a slight rounding off of the proximal medial edge at the cut femoral neck. These results encourage the use of this versatile stem which revealed good primary and secondary stability, with good load distribution along the femur.