Knee Diameter and Cross-Section Area Measurements in MRI as New Promising Methods of Chondromalacia Diagnosis-Pilot Study.

Background and Objectives: Chondromalacia often affects the knee joint. Risk factors for the development of cartilage degenerative changes include overweight, female sex and age. The use of radiological parameters to assess the knee joint is rarely reported in the literature. Materials and Methods: The study involved 324 patients, including 159 (49%) women and 165 (51%) men, with an age range between 8−87 years (mean: 45.1 ± 20.9). The studied group had a body mass index (BMI) in the range of 14.3−47.3 (mean: 27.7 ± 5.02). A 1.5 Tesla and 3.0 Tesla (T) MRI scanner was used to assess the cartilage of the knee joint using the Outerbridge scale. The radiological parameters analyzed were the Insall−Salvati index, knee surface area, knee AP (antero-posterior) maximal diameter and knee SD (sinistro-dexter) maximal diameter. Results: Parameters such as the knee surface area, knee AP maximal diameter and knee SD maximal diameter showed a significant correlation with Outerbridge Scale (p < 0.014). The age of the patients showed a significant correlation with each knee parameter (p < 0.004). Results of knee AP and SD maximal diameter measurements strongly depended on BMI level. Conclusions: A significant relationship was found between the knee surface area, knee AP maximal diameter and knee SD maximal diameter and the advancement of chondromalacic changes in the knee joint, age and BMI.