Lower Extremity Biomechanics in Obesity - Rehabilitative Perspective

Obesity is a major public health problem that has become a worldwide epidemic. Overweight and obesity are now dramatically increasing in developed countries impairing health-related quality of life and is a major cause for musculoskeletal disorders. Obesity is associated with static & dynamic biomechanical changes in trunk & lower extremities. This study aims to overview lower extremities Biomechanical changes in obesity & to provide clinical implications towards rehabilitative perspective. An extensive literature review using Ovid, Science direct, Pubmed, and Proquest. The results of the overview showed marked biomechanical alterations in lower extremity like reduced anteversion in the hip joint, varus and valgus malalignment in the knee-joint, reduced dorsiflexion in the ankle, pronated foot, metatarsus abductus, out toeing, and flat foot. Obese persons are characterized with physical inactivity, general deconditiong of the musculatures, and impaired neuromuscular function & co-activation. Comparatively the lower extremity strength is reduced than upper extremity and also impaired dynamic postural balance. The locomotion changes were evident both in kinematic and kinetic analysis. The kinematic changes include reduced cadence, velocity, step length, step frequency, reduced swing phase, increased step width and prolonged stance phase. Kinetic changes include increased hip flexor activity, increased knee flexion angle (early stance) and increased knee extension angle (stance phase). All available evidence states excessive & prolonged loading as a key factor for skeletal and neuromuscular abnormalities, which increases the prevalence of degenerative musculoskeletal disorders in obese persons. Consideration of this biomechanical adaptability might play a vital role in clinical decision making towards accurate estimation of contributing factors of musculoskeletal disorder. Since neuromuscular adaptation primarily results from osseous abnormalities, rehabilitation that promotes neuromuscular performance (endurance and neuromuscular coactivation) will be most valuable in management of obese.