From bench to bedside: a novel suture-augmented prosthesis for greater trochanteric fixation in osteoporotic hip arthroplasty.

Abstract

Background: Stable fixation of the greater trochanter during hip arthroplasty for unstable osteoporotic intertrochanteric fractures remains a significant challenge. Conventional techniques depend on securing the bone-implant interface, which is particularly compromised in osteoporotic bone. Here, we propose a novel conceptual approach that establishes a direct mechanical bridge from the abductor tendon to the prosthesis, thereby reducing reliance on the fragile bone-implant interface.

Methods: In this two-stage translational study, we progressed from biomechanical validation to clinical application. First, using a decalcified caprine femoral model simulating osteoporosis, three fixation constructs were compared: locking plate (LP), suture-augmented locking plate (LPSA), and Kirschner-wire tension band (KWTB). Ultimate load and construct stability were evaluated. Biomechanical testing confirmed the principle of suture-mediated load sharing and highlighted the intrinsic weakness of screw fixation in osteoporotic bone. Guided by these results, we designed a novel femoral prosthesis that eliminates screw fixation, employs sutures as the primary load-bearing element, and incorporates integrated suture anchor tunnels. This prosthesis was then assessed in a retrospective series of 15 consecutive elderly patients with osteoporotic intertrochanteric fractures. Clinical outcomes were evaluated using the Harris Hip Score (HHS).

Results: Biomechanically, the LPSA construct sustained a significantly higher ultimate load than the LP construct in decalcified bone (P < 0.001) and exhibited a greater load at 2-mm displacement than the KWTB construct (P < 0.001). Clinically, all patients achieved fracture union without prosthesis-related complications. The mean HHS at final follow-up was 88.27 ± 6.60, and 80% of patients regained independent ambulation.

Conclusions: A prosthesis-anchored, suture-mediated "tendon-to-prosthesis" load pathway provides reliable stabilization of the greater trochanter in osteoporotic bone. Biomechanical validation and favorable early clinical outcomes support the potential of this novel fixation strategy.