BMP-2 Linked to Bone Consolidation in Revision Total Hip Arthroplasty

Overview

Bone morphogenetic protein-2 (BMP-2) augmentation during revision total hip arthroplasty (THA) was associated with significant radiographic bone consolidation and favorable implant survivorship at midterm follow-up in patients with severe acetabular defects. The retrospective study demonstrated 83% of hips had over 50% bone consolidation and implant survivorship of 70% at 10 years based on all-cause reoperation.

Background

Revision total hip arthroplasty in patients with severe acetabular bone loss presents a significant surgical challenge due to compromised bone stock and implant stability. BMP-2 is an osteoinductive protein that may enhance bone regeneration and improve outcomes in complex reconstructions. This study evaluated the use of BMP-2 augmentation combined with cancellous allograft and demineralized bone matrix in revision THA for advanced acetabular defects, including cases with pelvic discontinuity. The goal was to assess radiographic bone consolidation, implant survivorship, and clinical outcomes over a midterm follow-up period.

Data Highlights

Key Findings

• 83% of hips showed more than 50% radiographic bone consolidation at final follow-up with no graft resorption observed.
• Implant survivorship was 90% at 6 years and 70% at 10 years based on all-cause reoperation; survivorship was 90% at both time points when using acetabular loosening as the endpoint.
• Postoperative complications occurred in 28% of hips, including infection (11%), dislocation (11%), and sciatic nerve palsy (6%).
• Reoperation was required in 11% of hips during the follow-up period.
• The surgical technique involved a layered approach combining cancellous allograft bone chips, BMP-2 collagen sponge, and demineralized bone matrix to address severe acetabular bone loss.
• Mean Oxford Hip Score was 35 at a mean of 84 months postoperatively, indicating functional improvement despite lack of preoperative patient-reported outcomes.

Clinical Implications

BMP-2 augmentation may enhance bone regeneration and improve implant stability in revision THA for patients with severe acetabular defects, potentially leading to better midterm implant survivorship. The layered grafting technique combining BMP-2 with allograft materials offers a promising approach to managing complex bone loss. However, clinicians should consider the risk of postoperative complications and the need for further research to establish safety and efficacy.

Conclusion

BMP-2 augmentation in revision total hip arthroplasty was associated with substantial radiographic bone consolidation and favorable implant survivorship at midterm follow-up in patients with severe acetabular defects. Further prospective studies are warranted to confirm these findings and optimize treatment protocols.

References

1. Heckmann et al., Arthroplasty Today, 2024 -- BMP-2 Augmentation in Revision Total Hip Arthroplasty