<prompt> Most serious complication of fracture of a long bone is: September 2005Fat embolismPulmonary embolismDeep vein thrombosisAssociated joint injuries  <response>: Ans. A: Fat Embolism A. Early complications: I. Local: Vascular injury causing haemorrhage, internal or external Visceral injury causing damage to structures such as brain, lung or bladder Damage to surrounding tissue, nerves or skin Haemahrosis Compament syndromeVolkmanns ischaemia Wound Infection, more common for open fractures II. Systemic: Fat embolism Shock Pulmonaryvenous thromboembolism B. late complications: I. Local: Delayed Union Non-union Malunion Joint stiffness Contractures Myositis ossificans Avascular necrosis AlgodystrophySudecks atrophy Osteomyelitis Growth disturbance or deformity II. Systemic: Gangrene, tetanus, septicemia Osteo-ahritis 