Patellar Tendon Rupture Following Total Knee Arthroplasty

Patellar tendon rupture following Total Knee Arthroplasty (TKA) is rare. There is no consensus on optimal treatment.

All patients who underwent a primary repair of a traumatic patellar tendon rupture following a TKA between 2008 and 2016, were retrospectively reviewed. Patient information, implant, repair type (anchor vs. bone tunnel), graft use, and complications were recorded.

Twenty-six patients met our inclusion criteria. The average age was 69.7+11 years. There were 19 females (73.1%). The average time from TKA to PT rupture was 13.6 months (range: 0- 135 months). The average incidence was 62.32 per 100,000 TKA. PT was repaired with anchors (A) in 9 (4 with a graft) and trans-osseous tunnels (TO) in 12 (5 required graft), and 5 with other methods. There was a significant improvement in KSS from 61 to 83 (P=0.023). There was a significant difference in time from PT tear to surgery in patients with grafts (42 days) and those without grafts (6 days) (P<0.001). Compared to A repair, TO had 2.39 times odds of re-tear (95% CI: 0.38,15.4; P=0.354) and 1.37 times odds of infection (95% CI:0.074,25.6; P=0.83). Repairs with a graft had a 1.90 times odds of re-tear (95% CI: 0.29, 12.19; P=0.49) and 6.3 time odds of infection (95% CI 0.26, 166.7; P=0.25).

Surgical repair of PT tears following TKA leads to significant clinical improvement, regardless of the fixation method or graft use. We found no difference in outcomes between A and TO repairs and or with graft use.