The Caton-Deschamps Index Reliability in Patellar Stabilization Surgery.

Recurrent patellofemoral instability is a multifactorial pathology based on limb alignment, soft tissue constraints as well as patella and trochlear groove abnormal anatomy. For a correct and effective surgical approach, an accurate radiological evaluation is essential, which consists of the evaluation of three main factors of instability: trochlear dysplasia, abnormal height of the patella and pathological distance of the anterior tibial apophysis and trochlear throat (TA-GT). Concerning patellar height, one of the most used methods is the calculation of the Caton-Deschamps radiographic index. However, to date there is no study that certifies its reproducibility and reliability from a pre-operative assessment and planning perspective.