The Proximal Placement of the Knee Joint in the 1-Stage Treatment of Infected Knee Revisions With Large Anterior Soft Tissue Defects

Introduction: No good mechanisms are available for reconstruction of large anterior soft tissue defects associated with infected total knees [periprosthetic joint infections of the knee (PJI-K)]. Patellectomy is usually required due to involvement with adjacent large anterior soft tissue defects left after radical debridement, free flaps are required for closure. This type of flap necessitates the use of a drop lock brace in ambulation. Our question is whether the proximal placement of the knee joint with longer tibial segments can reduce the number of free flaps and reduce the need for a drop lock brace by reattaching the quadriceps directly to the hinged tibial component. Methods: We retrospectively analyzed 35 cases with a minimum 2-year follow-up. Of 1-stage total knee revisions for PJI-K with the proximal placement of the knee joint for large anterior soft tissue defects left after debridement. Results: The average knee joint displacement was 85 mm. Eleven recurred with infection and 4 required amputation. Eighteen had enough extensor power to walk with a cane or walker as opposed to requiring a drop lock brace. Fifteen patients did not need any free or local flaps, rather these patients only required adjacent soft tissue transfer during surgery. Discussion: This novel proximal placement of the knee joint in patients with PJI-K who have large anterior soft tissue defects lessens the need for free flaps. The proximal placement also allows for reconstruction of what is left of the quadriceps mechanism into the tibial component and usually provides enough extensor power to lock the hinge joint.