Evaluation of recurrent dislocation of the patella in children with MRI: Goldthwait technique combined with lateral release, and VMO advancement—a retrospective study of 85 knees

Abstract

There are certain risk factors responsible for patella instability that should be identified before choosing the most appropriate treatment. We evaluated 83 skeletally immature patients who, after two or more patellar dislocation episodes, underwent surgical treatment to address the condition of patellar instability. Each patient was evaluated for patellar instability risk factors using the Balcarek patellar instability severity score. Evaluation of patellar instability included knee MRI to systematically identify anatomical risk factors. The preoperative and postoperative clinical evaluation included the modified Cincinnati score and the Kujala score. The Roux-Goldthwait technique combined with lateral retinaculum release and the advancement of the vastus medialis oblique (VMO) was performed on all knees. The mean patient age at the time of surgery was 12.2\u2009±\u20091.59 years (range 8–14 years). The average follow-up was 4.72\u2009±\u20091.37 (range 3–8) years. Trochlear dysplasia (decreased trochlear depth), the most common anatomical risk factor, was identified in 71 knees (83.5%). The modified Cincinnati score increased from 58.46\u2009±\u20098.75 (range 49–76) points to 94.07\u2009±\u20092.88 (range 88–98) postoperatively. The mean Kujala scores increased from 58.51\u2009±\u20098.94 (range 49–76) points to 93.66\u2009±\u20092.65 (range 87–98) postoperatively. The two-tailed P value was less than 0.0001. The patients were followed until their skeletal maturation, without reporting any incidents of patella dislocation, except one. The Roux-Goldthwait technique combined with lateral retinaculum release, and the advancement of VMO, can restore patellar tracking and can decrease the probability of another dislocation. It was an effective treatment in skeletally immature patients who had two or more episodes of patellar dislocation. IV.