Inguinal hernia Neurologic Muscular dystrophy Peripheral neuropathy Complex regional pain syndrome Neoplasia Benign bone tumors Malignant bone tumors Leukemia Intra-abdominal tumors Sacral tumors Spinal cord tumors Metabolic Rickets Hyperparathyroidism Hematologic Sickle cell disease Hemophilia Rheumatic conditions that may result in limp are numerous Many are accompanied by systemic symptoms and characteristic skin rashes Examples include Henoch–Schönlein purpura, erythema multiforme, acute rheumatic fever, juvenile idiopathic arthritis (JIA), dermatomyositis, and systemic lupus erythematosus Occasionally, limping from arthralgia will precede the development of the arthritis and systemic involvement An approach to the child with joint pain is found in Chapter 60 Pain: Joints , and a detailed discussion of arthritis is found in Chapter 101 Rheumatologic Emergencies In the absence of obvious trauma, fever, or systemic symptoms, the next step in the approach to the differential diagnosis of a limp is to determine the focality of the findings and the degree of pain Localized pain suggests repetitive microtrauma, bone tumor, or an acquired skeletal deformity Repetitive microtrauma may be responsible for osteochondrosis, a term referring to chronic inflammation of the physis and surrounding structures This condition is more common in boys, and can involve the pelvis, knee, or foot Osteochondrosis of the ischiopubic synchondrosis (Van neck disease), presents as vague groin or buttock pain in school-aged children Sinding-Larsen–Johansson disease involves the inferior pole of the patella, and Osgood–Schlatter disease involves the