Hoffa’s infrapatellar fatty body volume in patients with knee osteoarthritis: dependence on body mass index

BACKGROUND: Gonarthrosis is the most common form of osteoarthritis (OA) and chronic low-grade inflammation plays a central role in its pathogenesis. Obesity plays an important role in the development of gonarthrosis — it is also favoured by the presence of a relatively large fat depot in the knee joint — the infrapatellar fat pad (IPFP) — which releases pro-inflammatory cytokines and causes local inflammation in the knee joint. There is conflicting data on the relationship between IPFP volume, body mass index (BMI) and stage of gonarthrosis. Given the significant prevalence of OA in the population and the limited options for its effective treatment, it seems relevant to further investigate the role of BMI in the pathogenesis of gonarthrosis, which may further contribute to the development of new targeted therapeutic strategies. AIM: To evaluate the relationship between IPFP volume, BMI and stage of gonarthrosis in order to improve the effectiveness of preventive counselling and the possibility of further development of new treatment approaches. MATHERIALS AND METHODS: We retrospectively analysed the data of magnetic resonance imaging of the knee joints performed on 32 patients with gonarthrosis in 2022-2023 at the Centre for Radiological Diagnostics of the FEFU Medical Centre (Vladivostok, Primorsky Krai). The patients were divided into two groups according to their BMI. RESULTS: The mean IPFP volume for all patients in both groups was 33.01±8.79 cm3. Statistically significant differences were found when analysing the IPFP volume in men and women. Linear correlation analysis of the relationship between Hoffa's fat pad volume and OA stage in the female group showed a moderate inverse relationship and statistical significance. Multivariate statistical analysis showed that IPFP volume and BMI were most closely related to each other compared to other variables. No statistically significant differences in IPFP volume were found between the normal and increased BMI groups. A moderate negative correlation was found between BMI volume and OA stage in overweight patients. IPFP volume correlated with BMI in non-obese patients and weakly negatively in obese patients. CONCLUSIONS: In the present study, greater IPFP volume was observed in overweight and obese patients compared to those with normal BMI, but these differences were not statistically significant. In patients with gonarthrosis, IPFP volume was associated with comorbid obesity, gender, age, height and weight. These data may be useful in developing individualised approaches to the prevention and treatment of OA.