Outcomes After Abductor Reattachment to Proximal Femur Endoprosthesis After Tumor Resection.

Introduction: Resection of the proximal femur raises several challenges including restoration of the abductor mechanism. Few evaluated the outcomes of different techniques of abductor fixation to the proximal femur endoprosthesis.

Methods: A retrospective review of patients who underwent proximal femoral arthroplasty with a minimum follow-up of 12 months was conducted. Patients were divided into two groups: (1) those with preserved greater trochanter (GT) reattached to the implant and (2) those with direct abductor muscle reattachment. Both groups were compared for surgical and functional outcomes. Group 1 patients were subdivided into those who received GT reinsertion using grip and cables and those reattached using sutures.

Results: Fifty-three patients were included with a mean follow-up of 49 months. There were 22 patients with reinserted GT and 31 patients with soft-tissue repair. The endoprosthesis revision rate was comparable between groups (P = 0.27); however, the incidence of dislocations was higher in group 2 (0/22 versus 6/31; P = 0.035). Trendelenburg gait (77% versus 74%), use of walking aids (68% versus 81%), and abductor muscle strength were comparable between both groups (P > 0.05). In group 1, 15 patients had GT reinsertion with grip and cables. Of those, five patients (33%) had cable rupture within 13 months of follow-up. GT displacement reached 12 mm at 12 months of follow-up in patients with grip and cables compared with 26 mm in patients with GT suture reinsertion (P < 0.05).

Discussion: Although GT preservation did not improve functional outcomes, it was associated with a lower dislocation rate despite frequent cable failure. Less displacement was observed when GT reattachment used grip and cables.