The Patello-Femoral Joint Degeneration and the Shape of the Patella in the Population Needing an Arthroscopic Procedure.

Background: the main goal of the study was to investigate the prevalence of the articular cartilage defects (ACD) in the patellofemoral (PF) region of the knee joint based on the anatomical shapes of patella and its impact on the level of physical activity in the population needing arthroscopic procedures for all types of pathologies in the knee. Methods: The articular cartilage status of the PF region was obtained from 1098 arthroscopic procedures of the knee joint. The ACD were correlated to Wiberg's shape of the patella and classified according to the degree, size and depth of the ACD in the PF region using the ICRS (International Cartilage Repair Society) system: group I consisting of patients with Wiberg type I shape (W1), group II-patients with Wiberg type II shape (W2) and group III-patients with Wiberg type III shape (W3). The Tegner physical activity scale was used to evaluate the physical activity of the patients. Results: The mean of ACD size (PF region) in the W3 group was 3.10 +/- 0.99 cm(2), which was a statistically significantly larger area in comparison with the W1 (1.90 +/- 0.63 cm(2); p < 0.0000) and W2 (1.95 +/- 0.71 cm(2); p < 0.0000). The patients from the W3 group (mean 3.10 +/- 0.99) were less physically active (<4 Tegner) compared to the W2 group (mean of 4.48 +/- 0.88; p = 0.004) and W1 group (mean of 4.55 +/- 0.72; p = 0.002). Conclusions: The patients with the Wiberg type III patella shape had a higher incidence and larger size of ACD in the PF of the knee compared to the groups of Wiberg type I and II. Wiberg III patients with a lower level of physical activity had a larger size of ACD in the PF joint.