Use of Structureal Allograft in Revision Total Knee Arthroplasty

ABSTRACT

PURPOSE: To analyze the clinical and radiological results after revision total knee arthroplasty(TKA) using structural allograft for severe bone defect, MATERIALS AND METHODS: Between l992 and 1997, we used structural allograft for revision TKA in 20 knees of 18 patients with severe bone defect, The average age at surgery was of 61.6 years. The follow-up period averaged 43 months(range, 1 3-80 months). All patients had severe bone defect of the femur and/or tibia. Ten distal femur and thirteen proximal tibia required allografting. Fresh frozen femoral heads were used in all patients. We used posterior stabilized stemmed PFC knee component in all cases except one case with constrained condylar type. Patients were evaluated with physical examination, radiographs and the Hospital for Special Surgery knee rating scale. RESULTS: Average range of motion before surgery was 87degrees and after surgery 107degrees. Average knee score was 65 before and 90.4 after surgery. Preoperative alignment averaged 1.8degrees valgus, ranging from 17degrees varus to 13degrees valgus, and postoperative alignment averaged 7,2 degrees velgus, ranging from 3degrees valgus to 10 val-gus, All patient improved pain and stability. Postoperatively average HSS score improved from 65(rang- ing from 46 to 92) to 90.4(ranging from 75 to 100). All of the allografts united with host bone. There was no radiolucent line, lysis, fracture and infection. CONCLUSION: Structural allograft can be a satisfactory method of managing large bone defects in the failed total knee arthroplasty.