Are Knee and Foot Orthopedic Problems More Disabling in the Superobese?


Aiming to ascertain whether frequency and severity of knee and foot problems were different between morbid obesity (MO) and superobesity (SO), a prospective clinical study was designed.


Bariatric candidates (N?=?81, body mass index 40–81.3 kg/m2, 43.2 % with SO) were submitted to knee and foot radiologic assessment, baropodometric footprint measurement, and the questionnaires Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Foot and Ankle Outcome Score (FAOS). Main outcome measures were imaging diagnosis of knee osteoarthritis and flatfoot, along with functional impact on activities of daily living estimated by the questionnaires.


Knee osteoarthritis was radiologically diagnosed in 74.1 % (60/81), and the entire cohort suffered from flatfoot according to both footprint index and talar-first metatarsal radiographic angle; nevertheless, distribution was not different between SO and MO. However, WOMAC and FAOS scores were markedly worse in SO, affecting joint pain, stiffness, and general mobility. This is the first protocol of our knowledge to address foot and knee derangements in SO.


Functional impairment was more severe in SO, despite a morphologic pattern similar to MO. Even though amelioration is probable with weight loss, long-term orthopedic assistance might be required in such circumstances.

Keywords Superobesity – Morbid obesity – Knee osteoarthritis – Flatfoot – Footprint baropodometrym – Physical function – Osteoarthritis index – Disability