This document summarizes several common orthopaedic disorders: Septic arthritis is a joint infection that can be caused by bacteria. It requires drainage of the joint and intravenous antibiotics. Osteomyelitis is a bone infection that typically affects children. It is diagnosed via imaging and blood tests and treated with antibiotics and sometimes surgery. Ankle sprains come in three grades of severity and are initially treated with rest, ice, compression and elevation. More severe sprains may require bracing, casting or surgery.