Tibial Tubercle Osteotomy With Distalization Is a Safe and Effective Procedure for Patients With Patella Alta and Patellar Instability

Background: Tibial tubercle osteotomy with concomitant distalization for the treatment of patellar instability remains controversial, as it may cause anterior knee pain and chondral degeneration. Purpose: To evaluate radiographic, clinical, and functional outcomes in patients who had patellar instability with patella alta and underwent tibial tubercle osteotomy with distalization (TTO-d) as well as medial patellofemoral ligament reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Included in this study were 25 patients (31 cases) (mean age at surgery, 28.7 years; range, 14-33 years) with patellar instability and patella alta who underwent TTO-d with minimum 1-year follow-up. The Caton-Deschamps index (CDI), tibial tubercle-trochlear groove (TT-TG) distance, and amount of distalization were assessed. Clinical and functional variables included J-sign, anterior knee pain, apprehension test, Tegner activity level, and Kujala score. Results: The mean follow-up period was 2.62 years. The mean TT-TG was 16.15 mm (range, 7-24 mm); the mean CDI changed from 1.37 (1.25-1.7) preoperatively to 1.02 (0.9-1.12) postoperatively (P = .001); and the mean amount of tibial tubercle distalization was 8.80 mm (range, 4-16 mm). Lateral release (22 cases; 71.0%), medialization of tibial tubercle (17 cases; 54.8%), and autologous chondrocyte implantation (4 cases; 12.9%) were other associated procedures. The J-sign improved in 30 cases (96.8%; P = .001), and there was a complete resolution of anterior knee pain in 22 cases (71.0%; P = .001). An exploratory analysis showed that patellar cartilage defect severity was correlated with persistent pain (P = .005). The apprehension test became negative in all cases (P = .001). The median Kujala score increased from 52 to 77 (P = .001), and the median Tegner activity level improved from 3 to 4 (P = .001). No cases of osteotomy nonunion were reported. One case (3.2%) of patellar instability recurrence and 3 cases (6.5%) with painful hardware were observed. Conclusion: TTO-d resulted in good radiographic, clinical, and functional outcomes providing proper patellar stability to patients with patella alta. TTO-d appears to be a safe and efficient procedure with low complication rates, providing an additional tool for the personalized treatment of patellar instability.

Automated summary

The tibial tubercle osteotomy with distalization (TTO-d) for patellar instability in patients with patella alta, combined with medial patellofemoral ligament reconstruction, showed good radiographic, clinical, and functional outcomes with proper patellar stability. The procedure appeared to be safe and efficient, providing an additional tool for the personalized treatment of patellar instability, with low complication rates.