Management of extensor mechanism deficit as a consequence of patellar tendon loss in total knee arthroplasty: a new surgical technique.

Extensor mechanism disruption is an uncommon but devastating complication of total knee arthroplasty. A new technique of extensor mechanism reconstruction for patellar tendon loss, after total knee arthroplasty, with the help of extensor mechanism composite allograft is described. Four patients with chronic extensor mechanism-deficient total knee arthroplasty were undertaken for revision surgery along with reconstruction of extensor mechanism with an innovative technique using an extensor mechanism composite allograft consisting of a patella-patellar tendon-tibial tubercle. On final follow-up, none of the patients had extensor lag but for 10 degrees of extensor lag in 1 patient only. Providing an environment for bone-to-bone healing both proximally as well as distally and supervised postoperative rehabilitation led to encouraging results in the management of a failed extensor mechanism after total knee arthroplasty.