Assessment of the relationship between patellar volume and chondromalacia patellae using knee magnetic resonance imaging

OBJECTIVE: In this study, we evaluated the relationship between patellar volume and chondromalacia patellae. METHODS: A total of 162 patients who underwent knee magnetic resonance imaging (MR) due to knee pain at our department between January 2017 and May 2017 were included in this study. Of the cases, 111 were chondromalacia patellae, and 51 were healthy individuals. The patella volumes of all cases were analyzed using semi-automated software. Staging in cases with chondromalacia was graded according to the Outerbridge classification (stages 1–4). The relationship between patellar volume, presence of chondromalacia, cartilage thickness, age, and sex was analyzed statistically. RESULTS: Of the 162 cases, 67 (41.4%) were male, and 95 (58.6%) were female. The median age of the cases was 44. Patellar volume was a minimum of 12.24, a maximum of 39.44, and a median 21.4 cm3, and it was higher in cases with chondromalacia (p=0.026). In patients with chondromalacia patellae, the thickness of cartilage in the medial facet was lower. There was a statistically significant weak positive correlation between chondromalacia grade and patellar volume (p=0.031, r=0.204). CONCLUSION: This study showed that chondromalacia patellae, one of the important causes of chronic frontal knee pain, has a statistically significant relationship with patellar volume. The medial facial cartilage of the patella was thinner than in cases with chondromalacia patellae. Although the mean age of the cases with chondromalacia was higher than the cases without chondromalacia, there was no significant difference between male and female individuals.