Cement Mantle Screws in Periprosthetic Hip Fracture Fixation Near Well-Fixed Femoral Stems May Not Impact Short-Term Femoral Stem Survivorship.

BACKGROUND Vancouver Type-B1 and C periprosthetic hip fractures have traditionally been treated using single- or double-plate fixation constructs. Concern exists regarding screws within the cement mantle due to the theoretical risk of cement fracture and eventual prosthetic loosening. The aim of this study was to assess femoral stem survivorship in patients with Vancouver Type-B1 or C fractures around a well-fixed cemented femoral component who were treated with a plate construct and screws into the cement mantle. The hypothesis was that screw fixation into the cement mantle would not compromise stem fixation. METHODS A retrospective review was performed of patients who were consecutively, surgically treated for a periprosthetic fracture around a femoral stem by 3 surgeons, as identified through a search of records from January 1, 2007, to January 1, 2023. A total of 112 consecutive patients with Vancouver Type-B1 or C periprosthetic femoral fractures treated at our institutions were reviewed. Patients who underwent fixation using plate constructs with ≥1 screw within the cement mantle around the stem were included. Patients were followed until union, revision due to plate construct failure, or stem revision. Other complications, including alignment loss, cemented stem subsidence, radiographic stem loosening, and new cement-mantle fractures, were assessed. RESULTS Twenty-eight patients (19 female; 27 White or Caucasian; 3 Hispanic or Latino; mean age, 81.4 ± 8.7 years) met the inclusion criteria. Radiographic union was achieved in 26 patients (92.9%). The study included 8 (28.6%) interprosthetic fractures between a total hip arthroplasty prosthesis and a total knee arthroplasty prosthesis. The mean union time was 8.0 ± 4.6 months (range, 2.2 to 25.6 weeks). The mean follow-up duration following the index procedure was 33.3 ± 24.0 months (range, 6.1 to 86.2 months). Two nonunions occurred (7.1%), both involving plate failure. Both patients required revision of the femoral prosthesis, which was not loose at the time of reoperation. No stem subsidence or cement mantle fractures occurred during follow-up, and no revisions were performed for stem loosening. CONCLUSIONS Screw fixation into cement around a well-fixed stem did not contribute to stem loosening at short-term follow-up. There were no isolated femoral component revisions for cement mantle issues. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.