Dissociation and Subsequent Stable Malrotation of Femoral Stem Within Sleeve After Sivash-Range of Motion Total Hip Arthroplasty

Abstract

Case: A 78 year-old man fell 6 months after Sivash-range of motion (S-ROM) total hip arthroplasty (THA), after which he developed hip pain and external rotation deformity. Imaging showed stem malrotation in relative retroversion. Revision THA was delayed because of medical issues, occurring 1.5 years after the fall. No corrosion was observed intraoperatively at the stem-sleeve interface. His symptoms resolved after revision THA. Conclusion: We present a rare complication of S-ROM THA—dissociation of the femoral stem from the proximal sleeve, with subsequent re-engagement in static malrotation. No corrosion was observed, suggesting that the stem had stably reseated within the sleeve.