Radiographic evaluation and pain symptomatology of the knee in severely obese individuals - controlled transversal study.

Objective: To evaluate the prevalence of pain and radiographic degenerative arthritis in a group of severe obese patients (body mass index [BMI] > 35).

Methods: 41 patients with an indication of bariatric surgery were studied. The group of severely obese patients was subdivided into two subgroups: those with BMI < 50 and those with BMI > 50 ( n  = 14). They were compared to control group ( n  = 39). The following parameters were analyzed and correlated: radiographic arthritis by Kellgren-Lawrence's classification, tibiofemoral axis, gender, age, and knee pain (visual analog scale [VAS]). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to evaluate in 21 severe obese patients and IN 19 controls.

Results: A higher incidence of knee pain was observed in the severely obese group when compared with the control group ( p  < 0.0001, odds ratio: 2.96). In the severely obese group, increasing levels of pain with aging were observed ( p  = 0.047). A positive correlation was observed between the incidence of radiographic arthritis and increasing age in the severely obese ( p  = 0.001) and control ( p  = 0.037) groups. The WOMAC index results were worse in the severely obese group when compared with the control group ( p  = 0.001, odds ratio: 18.2).

Conclusion: A higher incidence of knee pain was observed in the severely obese group when compared with the control group. In the severely obese group, there increasing levels of pain with aging. A positive relation between the incidence of arthritis and increasing age was observed in the severely obese and control groups. The WOMAC index results were worse in the severely obese group.