Revision Total Knee Arthroplasty Using an Uncemented Metaphyseal Sleeve, Rotating Hinge Prosthesis: A Case Series of 99 Patients.

ABSTRACT

BACKGROUND: Hinge knee replacement is a salvage procedure with historically high failure and complication rates. We aim to analyze the use of an uncemented metaphyseal sleeve revision knee replacement in our unit-a third-generation rotating hinge knee prosthesis. This is the largest reported series of this implant with longest follow up. METHODS: We retrospectively identified 99 revision cases performed (2002-2018). In total, 67 of 99 (68%) cases were performed for aseptic etiology, whereas 32 of 99 (32%) cases were performed for infection. Clinical outcomes were assessed using the Oxford Knee Score, survivorship analysis, and incidence of revision/reoperations. Mean follow-up was 7 years (range 1.5-18). RESULTS: At follow-up, the mean Oxford Knee Score had improved from 10 points to 25 points. At mean 7 years of follow up, 18 of 99 cases had undergone revision giving a survivorship of 81% (90% aseptic). In total, 10 of 18 cases were performed for infection (10%) and 9 of 18 cases were performed for aseptic reasons (9%), of which 5 were for patella resurfacing (2 revision), 2 for failure of bony ingrowth, and 1 for fracture. Twenty-six patients (26%) had complications postoperatively, with patella disorders and reduced range of movement the most common. Patients who did not undergo patella resurfacing were significantly more likely to need revision of any cause (P = .01). CONCLUSION: This is the largest study of this prosthesis with longest follow-up. It demonstrates good survivorship and improvement in knee pain. Those with infection are at greatest risk of revision. Significant numbers have patella dysfunction/anterior knee symptoms therefore patella resurfacing should be considered when using this implant. LEVEL OF EVIDENCE IV.