Reconstruction of the extensor mechanism with fresh-frozen tendon allograft in total knee arthroplasty

Abstract

Purpose: Patellar tendon rupture after total knee replacement is a rare and highly limiting injury with multifactorial aetiology. Many reconstruction techniques have been described with not very predictable results. The use of allografts has been accepted as a suitable solution.

Methods: A series of seven patients with patellar tendon rupture treated with fresh-frozen tendon allograft reconstruction after knee arthroplasty is presented.

Results: Median follow-up is 25 months (20-31). Functional assessment improved, and the knee society score and knee functional score improved from 26 and 16 to 82 and 55, respectively. Median extension lag was 5° (0°-20°), with a median range of motion of 95° (70-100). Radiological study showed a rise of the patella of 22.26 mm.

Conclusion: The use of fresh-frozen allografts as a solution to patellar tendon ruptures after knee arthroplasty seems to provide acceptable results. Increased patellar height does not seem to affect functionality.