Reconstruction of Patellar Tendon Disruption After Total Knee Arthroplasty

Abstract

Patellar tendon disruption associated with total knee arthroplasty is an uncommon but potentially disastrous complication. Repair with isolated suture fixation is insufficient, and autograft and allograft tendon reconstruction techniques have variable results. The purpose of this study was to determine the results of a novel surgical technique in which readily available synthetic mesh is used for patellar tendon reconstruction. We retrospectively reviewed thirteen consecutive patients who underwent extensor mechanism reconstruction for subacute or chronic patellar tendon disruption following total knee arthroplasty at an average age of sixty years (range, thirty-seven to seventy-seven years). Five patients had already been treated unsuccessfully with an allograft extensor mechanism reconstruction and eight had a prior revision knee arthroplasty. The surgical technique included use of a knitted monofilament polypropylene graft to reconstruct the patellar tendon and to facilitate fixation of adjacent host tissue into the graft. Follow-up was available for all patients at a mean of forty-two months (range, eleven to 118 months). Three patients had evidence of failure of the graft reconstruction, all within six months. One patient with previous sepsis had recurrent infection and was treated with a knee arthrodesis. The remaining nine patients all demonstrated an extensor lag of no greater than 10° and have had no loss of extension at the time of final follow-up. Knee flexion was maintained in all patients (a mean of 103° preoperatively versus a mean of 107° postoperatively). The mean Knee Society scores for pain and function improved significantly (p < 0.01). Synthetic mesh was significantly less expensive than allograft for this reconstruction. The use of synthetic mesh to reconstruct a disrupted patellar tendon is a straightforward surgical procedure that was successful and durable in the majority of patients in our series. Compared with the use of an allograft, this technique eliminates the possibility of disease transmission and may be more cost-effective. No complications unique to the synthetic mesh were observed.