Outcomes and reoperation rates after tibial tubercle transfer and medial patellofemoral ligament reconstruction: higher revision stabilization in patients with trochlear dysplasia and patella alta

Abstract

PurposeTo determine the reoperation rate, risk factors for reoperation, and patient‐reported outcomes after isolated or combined tibial tubercle transfer and medial patellofemoral ligament reconstruction, for patellofemoral instability surgery. MethodsPatient’s records who underwent medial patellofemoral ligament reconstruction and/or tibial tubercle transfer for patellar instability by 35 surgeons from 2002 to 2018 at a single academic institution were retrospectively reviewed using CPT codes. Four‐hundred‐and‐eighty‐six patients were identified. Radiographic measurements, demographic parameters, and subsequent revision procedures and their indications were identified. A modified anterior knee pain survey was conducted by mail and with follow‐up phone survey. ResultsThe overall rate of reoperation was 120/486 (24.7%). The most common cause for reoperation was removal of hardware 42/486 (8.6%). The rate of reoperation for isolated medial patellofemoral ligament reconstruction 43/226 (19%) was lower than that of isolated tibial tubercle transfer 45/133 (33.8%) or a combined procedure 32/127 (25.2%) (P = 0.007). Woman had a higher rate of reoperation (29.4%) compared to men (15.9%) (P = 0.002). Patients at risk for a revision stabilization procedure included those with severe trochlear morphology (C or D) (6.1%) and those with Caton–Deschamps index > 1.3 (7.3%). Patients who underwent reoperation of any kind had poorer patient‐reported outcomes. ConclusionThe overall reoperation rate after patellofemoral instability surgery remains high, and any reoperation portends worse patient‐reported outcomes. Re‐operations for instability are more likely in patients with trochlear dysplasia and patella alta and may benefit from more aggressive initial treatment, such as medial patellofemoral ligament reconstruction and tibial tubercle transfer in combination. Using the results of this study, surgeons will be able to engage in meaningful discussion with patients to counsel patients on expectations postoperatively. Level of evidenceIV.

Two-type classification system for femoral trochlear dysplasia in recurrent patellar instability based on three-dimensional morphology

“…The novel 3D classification for trochlear dysplasia was developed to determine whether to perform trochleoplasty for each type. We also realize that the treatments for recurrent patellar instability extend beyond treating trochlear dysplasia [39, 40, 48, 49]. A comprehensive treatment algorithm is needed after assessing osseous and soft tissue risk factors.…”

The severity of patellar and trochlear dysplasia are correlated

“…The management of patellar instability is a surgical challenge and requires a tailored surgical strategy to achieve good functional results and a better quality of life [2, 20, 22]. Trochleoplasty in severe Dejour B or D trochlear dysplasia is essential even in the first‐line setting to achieve these results [12, 16, 19, 36, 37, 40]. However, the trochleoplasty technique generally depends on school or habit and does not take into consideration the type of trochlear dysplasia nor the degree of patellar dysplasia.…”

Quality of life following medial patellofemoral ligament reconstruction combined with medial tibial tubercle transfer in patients with recurrent patellar dislocation: a retrospective comparative study

“…Allen et al reported female gender was the risk factor for the lower scores of the International Knee Documentation Committee (IKDC) and Kujala score following MPFLr + TTT [ 46 ]. Compared with males, the reoperation rate of females was higher following MPFLr + TTT [ 20 ]. However, Watanabe et al studied the efficacy of MPFLr with or without TTT and found no effect of gender on the results [ 12 ].…”

“…The iMPFLr could not achieve promising results due to increased graft tension and potential failure caused by the TT lateralization, which produces anisometry in MPFLr [ 19 ]. Therefore, a combination of MPFLr and TT transfer (TTT) for patients with an increased TT–TG distance, especially when TT–TG distance is greater than 20 mm, should be taken into consideration, with the purpose of addressing both patellar dislocation and patellar maltracking at the same time to restore the optimal position of patella relative to the femoral trochlea [ 5 , 18 , 20 ]. A systematic review showed that MPFLr combined with TTT is a safe and effective surgery, with a low to moderate risk of complications and overall good results [ 21 ].…”