Introduction

Patellofemoral Osteochondral lesions are an important and prevalent cause of anterior knee pain. Cases that require a surgical resolution through microfracture procedure present arguable results. Diverse adjuvant treatments have been developed to support microfracture treatment like the use of Chitosan scaffolds which objective is to stabilize the clot maintaining it over the defect longer thus improving the quality of the fibrocartilage and clinical results.

Objective

To assess the clinical and radiological results of osteochondral lesions treated with microfracture surgery associated with chitosan scaffold through clinical scores and MRI assessments.

Methods

A retrospective observational analytical study was performed. Fifteen patients with osteochondral lesions (IV grade, ICRS) on patellar and trochlear regions diagnosed by magnetic resonance imaging (MRI) without response to conservative treatment and submitted to a micro-fracture procedure with chitosan scaffold were included. Quantity and quality of the reparation cartilage was assessed with the MOCART2.0 score on post-operative MRI, as clinical outcomes were evaluated with pre and post-operative Kujala score tests. Shapiro-Wilks test for normality was applied as well as Wilcoxon’s signed rank test and Kruskal Wallis-H test for clinical scores within subjects and lesion location subgroups comparisons. One-factor analysis of variance (ANOVA) test was used for imaging subgroups comparison, with p<0.05 defined as statistical significance.

Results

Statistically different medians were reported in the within subject’s assessment of pre and post-operative Kujala score with a positive difference of 19 (Standard error = 17.6) for the post-operative median (p < 0.001). No statistical difference was found through the clinical location assessment (p = 0.756), as well as the cartilage imaging assessment (p = 0.756).

Conclusions

Treatment of patellofemoral compartment grade IV ICRS osteochondral lesions with microfractures surgery associated with chitosan scaffold proved to be effective in defect filling and symptomatic reduction.