Abstract
Background
Primary dislocation of the patella is a common acute knee disorder in children, adolescents and young adults. While primary dislocation of the patella has traditionally been treated non-operatively, primary operative repair of the medial patella-stabilizing soft tissues has been popularized more recently and thought to reduce the risk of dislocation. However, several studies have shown substantial rates of redislocation with longer follow-up time, irrespective of treatment. The purpose of this systematic review was to compare operative and non-operative treatment for primary dislocation of the patella, regarding redislocation rates and symptoms.
Methods
Based on a systematic literature search of the medical literature from 1950 to 2010, three randomized and two quasi-randomized controlled clinical trials comparing surgical stabilization with non-operative treatment for patients with primary patellar dislocation were selected. The Risk of Bias Tool (Cochrane Handbook, 2008) was used to assess the quality of the studies included. Study results were pooled using the fixed-effects and random-effects models with mean differences and risk ratios for continuous and dichotomous variables, respectively. Heterogeneity across studies was assessed with Q test and I-square statistic. A sensitivity analysis was performed by assessing the change on effect size by eliminating each single trial.
Results
In total, 341 patients from 5 trials were included. 158 patients were treated non-operatively and 183 patients were treated operatively. For primary outcome of patellar redislocation, while significant heterogeneity was found using the random-effects model, no significant difference was observed between the treatment groups (pooled RR=1.36, 95% CI 0.8–2.31, p=0.25). No significant difference was observed between the treatment groups (pooled RR=1.36, 95% CI0.8–2.31, p=0.25). No significant differences were found between both groups for symptoms ofinstability (RR of 1.24, 95% CI 0.96–1.59, p=0.10), Kujala knee score (−5.66, 95% CI −15.51 −4.19, p=0.26) or requirement for later surgery (RR=0.92, CI 0.61–1.39, p=0.69).
Conclusions
This meta-analysis found no differences in patellar redislocation rate, patient reported instability symptoms, Kujala Knee score and rate of later surgery after initial treatment, between operative and non-operative treatment of primary patellar dislocation.
Level of evidence
Level II.
