Effects on patellar chondromalacia of the size of the infrapatellar fat pad

Özet

Infrapatellar fat tissue (IPFP), which is placed in the anterior compartment, has a vital role in the biomechanics of knee. It is thought that infrapatellar fat pad, which also functions as a storage for repair cells after injury, has a protective effect in mechanical and inflammatory knee pain. In this study, the relationship between patellar chondromalacia, which is among significant causes of anterior knee pain, and the sizes of IPFP was investigated. MRI images of patients over 18 years of age, who underwent MRI examination in June 2017 - December 2017, were examined retrospectively by recovering from the electronic patient registration system in the hospital. Eighty-three cases had patellar chondromalacia with normal-healthy IPFP tissue in the examination of knee MRI, and 53 cases without chondromalacia were included in the study. The average age of all evaluated 134 patients was 37.8 (22-68) years. The degree of chondromalacia patella was made according to Outerbridge classification. The height and depths of IPFP in all cases were measured from the widest site on the T1-weighted MRI images in the sagittal plane. The relationship among age, gender, the degree of patellar chondromalacia and IPFP sizes were evaluated. While the average of 51 patients without patellar chondromalacia was 29.04 (22-51) years, the average of 83 patients with chondromalacia was 43.20 (27-68) years. According to Outerbridge classification, patellar chondromalacia grade 3 in 14 patients, grade 2 in 41 patients, grade 1 in 26 patients and grade 4 in 2 patients were observed. It was not seen a significant difference between the groups in terms of gender (p = 0.78). It was seen a significant increase in between patellar chondromalacia and increasing age (p <0.001). It was observed that while IPFP height was averagely 35.33 mm and IPFP anteroposterior width was 17.29 mm in the patients with patellar chondromalacia, IPFP height was averagely 38.65 mm, and IPFP anteroposterior width was averagely 19.49 (15-37) mm in the patients without chondromalacia. It was observed a statistically significant increase in the frequency of patellar chondromalacia as the size of the IPFP tissue decreased (p<0.001). Incidence of patellar chondromalacia increases both with increasing age and a decrease in IPFP sizes. We consider that IPFP tissue has a contribution to joint cartilage in both biomechanical and physiological levels. For this reason, protection of IPFP tissue is required in both the prevention of patellofemoral joint degeneration and in the decrease of anterior knee pain during knee arthroscopy or arthroplasty interventions.