Analysis of limb alignment in the pathogenesis of osteoarthritis: a comparison of Saudi Arabian and Canadian cases.

A study was made of alignment abnormalities and bone deformities in Saudis with osteoarthritis (SOA). Data from standardized radiography of hips and knees were: hip-knee-ankle angle (HKA), condylar-hip angle (CH), tibial plateau-ankle angle (PA), and joint surface (condylar-plateau) angle (CP). Females dominated the <50 years SOA subgroup (1.8:1), having also early onset OA with severe bowlegged deformity (mean HKA -11 degrees) and major shifts in CH, PA, and CP relative to normal parameters. In the females, links were noted between severe disease and osteomalacia or osteoporosis, requiring prospective studies. An association between femoral deformity (CH) and OA, first reported in Canadians with OA (COA), was confirmed in SOA (especially in males of all ages). The condition implies heightened mechanical risk of onset or progression at medial joint surfaces. Further, it calls for the fresh appraisal of surgical options based on biomechanical analysis of each case, including femoral osteotomy where necessary.