Prevalence of Bone Edema-like Lesions in Patients with Knee Osteoarthritis

Context: The presence of subchondral Bone Edema-Like Lesions (BELs) in patients with Knee Osteoarthritis (OA) is associated with increased pain and a faster progression of OA. However, the exact prevalence of BELs is controversial due to contradicting findings reported in previous studies. Aim: To evaluate the prevalence of BELs by Magnetic Resonance Imaging (MRI), in patients with adjacent full-thickness cartilage loss of the knee. Settings and Design: Single center cross-sectional study. Methods: We evaluated 100 consecutive MRI studies of patients with Kellgren and Lawrence grade IV knee osteoarthritis from April 2019 to May 2019. The primary outcome of the study was to evaluate the prevalence of BELs. The secondary outcome was to evaluate the association of BELs with the demographic characteristics of patients including age, sex, body mass index, presence of osteophytes, and previous diagnosis of osteoporosis or osteopenia. Results: All patients had pain at the time of MRI evaluation. The average age was 66.5 ± 10.1 years and the average body mass index was 27.3 ± 5.1 kg/m². A total of 86 patients (86%) had BELs on the evaluated MRI, with both male and female patients being equally affected (P=0.405). No demographic characteristic showed a significant association with the presence of BELs. However, while not statistically significant, male patients, patients with obesity, and patients with osteophytes had an increased risk of having BELs. Conclusion: The majority of patients with symptomatic grade IV knee osteoarthritis have BELs on MRI evaluation. No demographic characteristic was associated with a greater risk of presenting BELs.