Effect of Poly-L-Lactic Acid Mesh Augmentation on Cyclic Gap Formation in Transosseous Patellar Tendon Repair: A Biomechanical Study

Patellar Tendon Ruptures after Total Knee Arthroplasty

Patellar tendon (PT) rupture following total knee arthroplasty (TKA) is a rare, but devastating complication. These injuries occur most frequently in the acute period following TKA due to trauma to the knee. PT ruptures that disrupt the extensor mechanism create a marked functional deficit, impacting every facet of daily life. In complete ruptures of the PT, repair or reconstruction is typically indicated; however, complication rates following intervention remain high. Operative intervention remains the mainstay of treatment, with only certain specific situations where nonoperative intervention is appropriate. Operative techniques are chosen based on the acuity, location of disruption, and status of the residual soft tissues. Treatment options include repair with or without augmentation or reconstruction. Augmentation does reduce the high risk of complications, bringing rates down from 63 to 25%. Augmentation options include autografts, allografts, synthetic grafts, or synthetic meshes. Despite advancements, outcomes are unpredictable and complications are common, highlighting the need for further research to improve treatment protocols. This article provides an overview of PT ruptures following TKA, the various treatment options, and the recommendations of the M.M., R.D., G.S. for each common type of PT injury encountered.

Acute Patellar Tendon Ruptures: An Update on Management

Patellar tendon ruptures can be debilitating injuries. When incomplete, partial tears can be managed nonsurgically with immobilization and progressive rehabilitation. Although complete ruptures remain a relatively uncommon injury, they portend a high level of morbidity. Ruptures typically result from an acute mechanical overload to the extensor mechanism, such as with forced quadriceps contraction and knee flexion. However, chronically degenerated tendons are also predisposed to failure from low-energy injuries. Diagnosis can often be made clinically with recognition of a palpable defect to the tendon, localized patellar tendon tenderness, and inability to actively extend the knee. Diagnosis and surgical planning can be established with radiograph, ultrasonography, or magnetic resonance imaging. Surgical repair is the mainstay of treatment, and there have been many recent advances in repair technique, optimal reconstruction strategies, and supplemental fixation. Time to surgery for complete tears remains the most important prognosticator for success. Direct primary repair can be completed with transosseous tunnels, suture anchor repair, or end-to-end repair. Tendon reconstruction can be achieved with or without mechanical or biologic augments. Rehabilitation programs vary in specifics, but return to sport can be expected by 6 months postoperatively.