Leg pain in children has a broad differential diagnosis and includes more innocuous problems such as growing pains and transient synovitis but also more serious problems including neurological diseases or malignancy. Occult or self-limited trauma are also common causes. A review can be found here. Limping can be painful or painless and has its own differential diagnosis which can overlap with leg pain. A differential diagnosis for limping can be found here. Muscle weakness also has its’ own differential diagnosis which can be found here.
Benign acute childhood myositis (BACM) has other names including viral myositis, acute myositis, influenza-induced myositis, or myalgia cruris eidemica. It is a benign acute myositis that occurs usually during the late winte…