Causes of neck pain include: 1  Abnormalities in the bone or joints. 2  Trauma. 3  Poor posture.  Degenerative 1  diseases. Tumors.  Muscle strain.
1 Repetitive, excessive sports, especially in the form on running, can lead to trauma that creates leg pain - E.G: shin splints and stress fractures. 2  Leg pain with an underlying medical cause may be nerve-related, musculoskeletal or vascular.  Some forms of leg pain resolve with self-help care.
Quick Answer. The causes of leg muscle pain and weakness include various conditions, such as deep vein thrombosis, gout, various injuries and sprains, according to Mayo Clinic. Other causes of leg pain and weakness are osteoarthritis, sciatica and varicose veins. Continue Reading.