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Assessment/Diagnosis
Biomechanical Complications and Musculoskeletal
Disorders
➤ Obesity imposes substantial biomechanical (fat mass disease)
and metabolic stress (adiposopathy) on the musculoskeletal
system, increasing the risk of a range of disorders across the
lifespan. Excess fat mass, particularly central adiposity, alters
posture, gait, and joint loading, while adiposopathy-driven
inflammation further accelerates tissue degeneration.
Osteoarthritis/Degenerative Joint Disease
➤ Osteoarthritis, the most common form of arthritis, involves
progressive degeneration of articular cartilage and is
highly prevalent among individuals with obesity due to
both mechanical (fat mass disease) and inflammatory
mechanisms (adiposopathy). Excess body weight increases
joint loading, particularly in weight-bearing joints, with each
pound lost reducing knee load by approximately four pounds
during ambulation. Additionally, adipose tissue secretes
proinflammatory adipokines such as leptin, resistin, TNF-α,
and IL-6, which promote low-grade systemic inflammation and
contribute to cartilage degradation and synovial inflammation,
even in non–weight-bearing joints. Leptin, in particular,
enhances the production of matrix metalloproteinases and nitric
oxide, further accelerating cartilage breakdown.
➤ Clinically, joint disease commonly presents with activity-related
pain that is initially relieved by rest but may become persistent
and disrupt sleep as the condition advances. Additional features
include stiffness lasting less than 30 minutes after inactivity
(the gelling phenomenon), reduced range of motion, crepitus
during joint movement, swelling or effusion with tenderness, and
osteophyte formation, which is often palpable as Heberden nodes
at the distal and Bouchard nodes at the proximal interphalangeal
joints. Involvement of lower extremity joints may also result in
limping or altered gait.
