Post-TKA Patellar Tendon Rupture? New Study Has Answers

With the knowledge that things don’t turn out so well for those who experience a patellar or quadriceps tendon ruptures after total knee arthroplasty (TKA), a team of researchers set out to bring the orthopedic community closer on a consensus regarding optimal treatment.

The study, “Treatment of Extensor Tendon Disruption After Total Knee Arthroplasty: A Systematic Review,” was published in the February 27, 2019 edition of The Journal of Arthroplasty.

Timothy L. Miller, M.D., associate professor in the Department of Orthopaedic Surgery at The Ohio State University Wexner Medical Center and study co-author explained the genesis of the study to OTW, “We recently had a patient present with patellar tendon rupture after total knee replacement that required repair. However, she re-ruptured her repair and we were stumped as to how to counsel her and which treatment option would be the best going forward.”

“This case served as the impetus to research this topic. Furthermore, a recent conference was held among the sports medicine and total joint replacement faculty at our institution regarding the treatment of recurrent patellar tendon ruptures and post-total knee replacement extensor mechanism ruptures.”

“This included a discussion of the devastating effect that an extensor mechanism rupture, particularly patellar tendon rupture, has on the knee following total knee arthroplasty as well as the need for allograft reconstruction in this population. We were searching for a treatment algorithm for this injury and decided to embark on this project.”

First author Sravya P. Vajapey, M.D., a third-year orthopedic resident at The Ohio State University Wexner Medical Center expanded on Dr. Miller’s comments to OTW, “Repair of patellar tendon ruptures in post-arthroplasty knees has a high rate of complication including re-rupture and extensor lag of 30 degrees or more. Rate of extensor lag and other complications following allograft tendon reconstruction for patellar tendon rupture and quadriceps tendon repair are much lower than that of patellar tendon repair after total knee arthroplasty.”

For their study the authors found 28 articles that met their inclusion criteria. They noticed that the complication rate after repair of patellar tendon (63.16%) was higher than the complication rate after repair of quadriceps tendon (25.37%).

However, the researchers also noticed that the complication rate for patellar and quadriceps tendon tears after autograft, allograft, or mesh reconstruction was similar (18.8% vs 19.2%, respectively).

According to the authors, “The most common complication after extensor mechanism repair or reconstruction was extension lag of 30° or greater (45.33%). This was followed by re-rupture and infection (25.33% and 22.67%, respectively). Early ruptures had a higher overall complication rate than late injuries.”

Dr. Miller told OTW, “Our findings support the use of patellar tendon reconstruction in both acute and chronic patellar tendon ruptures following a total knee arthroplasty particularly given its lower complication rate compared with primary repair. Unlike patellar tendon ruptures, acute quadriceps ruptures following total knee arthroplasty do well with repair while chronic or recurrent quadriceps ruptures benefit most from reconstruction.”