[Treatment of objective patellar instability. Results after five years of follow-up]

To present the different surgical procedures in the treatment of objective femoropateral instability, including osteotomy of anterior tibial tuberosity and femoral trocleoplasty.

With a prospective 5-year follow-up design that included 21 patients (21 knees) treated for relapsing patellar dislocation between March 2010 and August 2014, treated surgically using 2 different techniques depending on the type of basic structural instability. To determine this, the Caton-Deschamps X-Ray Index (for the evaluation of the patellar height) and tomographic parameters were analyzed to assess the troclear configuration and distance from the anterior tibial tuberosity to the femoral trochlea (TT-TG) in the overlapping of images in the axial plane.

We have had satisfactory results both with the transfer of the anterior tibial tuberosity and with the trocleoplasty. In both procedures, a reconstruction of the medial patelo-femoral ligament (LPFM) was performed.

Recurrence of instability is very rare after these procedures and is more likely to result from undiagnosed or underestimated associated abnormalities. Precise preoperative planning is required to determine the patellar height, location of the anterior tibial tuberosity, and troclear configuration for satisfactory results.