Short-term results of hip revisions with a curved cementless modular stem in association with the surgical approach

Abstract

A prospective study was designed to test the hypothesis that short-term results after hip revisions are in association with the surgical approach with lower clinical scores for the transfemoral approach. A total of 120 hip revision operations with the modular cementless revision stem "Revitan Curved" (Zimmer GmbH, Winterthur, Switzerland), of which 42 replacements involved an endofemoral (posterolateral) approach and 78 implantations a transfemoral approach, were followed up over a period of at least 24 months. In the early post-operative stage, stems implanted transfemoral were associated with significantly lower Harris Hip Scores and a significantly more frequent appearance of Trendelenburg signs. The differences lessened at the end of the follow-up period. Within the group of transfemoral implantation, all six stems with a circular fixation zone measuring less than 3 cm had subsided and two of these had become loose; none of the stems with greater fixation zones exhibited these properties. In the case of the endofemoral implants, three stems exhibited sinking but there did not appear to be any relationship between this event and length of fixation zone. The surgical approach has an association with the short-time outcomes of hip revsions using cementless modular stems. Transfemoral implantation of the "Revitan curved" stem requires a fixation zone of at least 3 cm and a longer period of rehabilitation.