[Outcomes of Surgical Treatment for Patellar Tendinopathy with Particular Consideration of Patella Alta]

Patella alta is considered an intrinsic risk factor for patellar tendinopathy. From a biomechanical perspective, distalizing tibial tubercle osteotomy (d-TTO) can improve the force relationship between the patellar tendon and the quadriceps tendon, thereby representing a potential surgical indication in cases of recalcitrant patellar tendinopathy and concomitant patella alta. However, clinical evidence supporting this approach remains scarce.

A total of 23 patients (21 male, 2 female; age: 34 ± 7.8 years) who underwent arthroscopic patellar tendon debridement between January 2018 and September 2022 were included. In nine patients, an additional d-TTO was performed to correct patella alta. Based on the preoperative Caton-Deschamps Index (CDI), patients were assigned to one of three groups: (1) patella norma group (n=8; CDI 1.04 ± 0.07), (2) borderline group (n=6; CDI 1.25 ± 0.05), and (3) patella alta group (n=9; CDI 1.35 ± 0.13). The latter group was treated with an additional d-TTO. Outcomes were assessed using the Victorian Institute of Sport Assessment-Patella (VISA-P) questionnaire, the patellofemoral subscale of the Knee Osteoarthritis and Outcome Score (KOOS-PF), and the Marx Activity Rating Scale (MARS).

The follow-up period was 43.7 ± 9.4 months. Across the overall cohort, the VISA-P score improved significantly from 33.6 ± 19.7 points preoperatively to 86.4 ± 14 points postoperatively (p < 0.0001). Similarly, the KOOS-PF score increased significantly from 30.5 ± 21.4 points preoperatively to 78.6 ± 21.2 points postoperatively (p < 0.0001). The MARS increased non-significantly from 5.7 ± 6.0 to 6.5 ± 5.8 (p = 0.6). Preoperatively, there were no significant differences between groups. Postoperatively, however, the KOOS-PF score was significantly lower in the borderline group (56.5 ± 26.5 points) compared with both the patella norma group (87.8 ± 13.3 points) and the corrected patella alta group (85.1 ± 11.9 points) (p = 0.006). A similar trend was observed for the VISA-P score (93.7 ± 7.6 vs. 76.8 ± 19.3 vs. 86.2 ± 11.6; p = 0.075), although this did not reach statistical significance (P = 0.075).

Surgical treatment of patients with recalcitrant patellar tendinopathy resulted in significant improvements in both VISA-P and KOOSPF scores. Simultaneous correction of patella alta achieved outcomes comparable to the patella norma group. The findings also suggest that a high-normal Caton-Deschamps Index (Borderline group) may influence postoperative outcomes.