Revision total knee arthroplasty using metaphyseal sleeves at short-term follow-up.

Abstract

The treatment of bone loss in revision total knee arthroplasty (TKA) has involved using revision implants in association with cement, augments, particulate, and structural allograft. Newer metaphyseal augments were introduced to allow for metaphyseal fixation of the prosthesis while managing significant bone loss. The purpose of the current study was to evaluate the outcome of revision TKA using metaphyseal sleeves. The authors prospectively followed 96 knees that underwent revision TKA with metaphyseal sleeves. Eighty-three knees met the minimum 2-year criteria for follow-up. Thirty-six sleeves were used in femoral revisions and 83 sleeves were used in tibial revisions. The defects were classified according to the Anderson Orthopaedic Research Institute classification. Femoral defects were classified as type I in 4 knees, type IIb in 25 knees, and type III in 7 knees. Tibial defects were classified as type I in 9 knees, type IIa in 1 knee, type IIb in 68 knees, and type III in 5 knees. The patients were followed for an average of 2.4 years (range, 2.0-3.7 years). Mean Knee Society function score improved from 47.9 to 61.1 points. Mean Short Form 36 physical score improved from 43.3 to 56.3 points. Mean Western Ontario and McMaster Universities Arthritis Index improved from 55.3 to 25.9 points. None of the implants demonstrated progressive radiolucent lines around the metaphyseal sleeves. At final follow-up, only 2 (2.7%) tibial components required revision for aseptic loosening. At short-term follow-up, revision TKA with metaphyseal sleeves provided reliable fixation. This is especially encouraging given the severe nature of bone loss in the majority of patients in whom a metaphyseal sleeve was used. Long-term follow-up is needed to demonstrate the true effectiveness of these devices.