Risk factors for subsidence of modular fluted tapered stem implanted by using transfemoral Wagner approach during revision hip arthroplasty

Purpose To determine clinical and radiographic risk factors for the vertical subsidence of modular fluted tapered stems implanted using the transfemoral Wagner approach in a cohort of revision hip arthroplasties. Methods A retrospective review of a single-centre surgical registry was performed. Patients who underwent a revision total hip arthroplasty, in which the uncemented modular fluted tapered stem (REVISION Hip/Anca-Ti6Al4V, LimaCorporate, Udine, Italy) was implanted using the transfemoral Wagner approach, were identified. Patient’s demographic data, clinical and radiographic outcomes and post-operative complications were assessed. As a significant subsidence, a 5-mm cut-off was chosen. Results We identified 278 revision hip arthroplasties with a mean follow-up of 35 months. The median of subsidence in the group of 5 mm and less was 2 mm, and 17 mm in the group of subsidence of 5 mm and more. A negative correlation was found between the stem subsidence and the length of good contact between the medial and lateral cortical bone and the stem (medial, − 0.248; P