Combined trochleoplasty and medial patellofemoral ligament reconstruction reduces patellar height

Abstract Purpose This study assessed whether trochleoplasty combined with medial patellofemoral ligament reconstruction (MPFLR) reduces patellar height, potentially obviating the need for distalizing tibial tubercle osteotomy (TTO). Methods Patellar height was evaluated in 73 knees before and at a median of 6 months after patellar stabilisation using the Caton–Deschamps (CDI), Insall–Salvati (ISI) and Blackburne–Peel (BPI) indices. Results MPFL reconstruction with trochleoplasty resulted in a sustained 8.1% postoperative reduction in the CDI (95% confidence interval [CI]: −14.1% to −2.1%; p < 0.001). The reduction was greater with MPFLR plus TTO (16.5%; −23.7% to −9.3%; p < 0.001) and maximal when MPFLR, trochleoplasty and TTO were performed together (22.9%; −33.1% to −12.6%; p < 0.001). ISI and BPI showed comparable reductions. While strong Pearson correlations among the indices ( r = 0.6–0.9; all p < 0.001) were observed preoperatively, Bland–Altman analyses revealed a substantial bias of up to 25%. Inter‐index agreement for clinical classification (alta, normal, baja) was inconsistent, achieving at best a ‘moderate’ level (Weighted Cohen's kappa 0.36–0.60). Conclusion Combined MPFL reconstruction and trochleoplasty reduce patellar height by approximately 10%. The interaction effect of various surgical procedures for PFI on patellar height, coupled with methodological inconsistencies in index‐based patellar height classification, challenges the validity of rigid cut‐off values for distalizing TTO. Level of Evidence Level III.