A Novel Technique for Medial Patellofemoral Ligament Reconstruction Using Vertical Patellar Tunnels and Use of a Single Implant. Technical Note

Abstract

P atellar instability is a common pathology with an estimated incidence in the general population of 5.8 cases per 100,000, increasing to 29 cases per 100,000 in younger groups (10 to 17 y). This condition presents a rate of recurrence after the first dislocation episode of 15% to 44% and over 50% after the second episode. It also presents a high persistence of mechanical symptoms after the first episode of dislocation, where 50% of patients not resuming their previous physical activity are described and up to 70% suffer some degree of functional limitation.1 This pathology has a multifactorial etiology, with anatomic and biomechanical aspects involved, within which a patellar malalignment, genu valgus, patella alta, and increased patellar tilt can be found, in addition to predictors of redislocation such as the presence of trochlear dysplasia. The medial patellofemoral ligament (MPFL) is deemed as 1 of the main stabilizing structures of the patella, mainly in the first 30 degrees of flexion, which is frequently injured in cases of patellar instability, up to 94% in some series.2 Reconstruction of the MPFL can be performed alone or in combination with a tibial tubercle osteotomy, usually carried out with a tibial tuberosity-trochlear groove measurement > 20 mm. Our group generally performs an isolated reconstruction of the MPFL, reserving the distal realignment only for those cases with clinical lateral patellar chondrosis, as recommended by Elizabeth Arendt.3 Regarding MPFL reconstruction, we present a technique that to the best of our knowledge, has not been published, with which we have had good preliminary clinical results with a low rate of redislocation (3 cases in 86 operated knees) and improvement in Kujala scores (37 to 79 in our series). ANATOMY