• hip osteoarthritis
• knee osteoarthritis
• shoes

Osteoarthritis (OA) is among the most common types of joint disease and a frequent cause of pain and physical disability. It is the fourth most frequent predictor of health problems worldwide in women, and the eighth in men¹; in countries such as the United States, United Kingdom, or Canada its total economic costs have been estimated as 2% of the gross national income, second only to cardiovascular diseases.² OA is now considered as a dynamic process in which what appears to be the consequences of the older idea of mechanical wear and tear of the joint coincides with remodelling of joint structures, increased cartilage turnover, incomplete repair and new bone formation, more marked in the joint margins.^3,4 Joints at the lower extremity, mainly knees and hips, are frequently affected in primary OA, resulting in various degrees of walking pain and difficulty. Although the causes of primary OA remain undefined, it is well established that mechanical factors play an important part in its development and progression. Obesity is an important risk factor for symptomatic knee OA,⁵ and both men and women with a body mass index of 30 to 35 have a fourfold increase of knee OA compared with normal weight controls.⁶ Prospective data on women suggest that the risk for known OA increases by about 15% per each kg/m² of body mass index above 27, and that reduction of a similar weight resulted in a similar decrease of incident knee OA,⁷ proving that this is a modifiable factor. At the knee, being overweight is also a risk factor for the development of OA at the patellofemoral compartment. …