Causes of severe middle back pain include medical conditions and syndromes such as a herniated disk, spine tumors and fibromyalgia, according to Healthgrades. Severe middle back pain is commonly caused by a sudden movement during home improvement projects or when playing sports.
A herniated disk is a common cause of back pain and occurs when adjacent vertebrae in the spine force the nucleus pulposus to press on the nerves near the disk, notes Cleveland Clinic. A herniated disk in the mid back causes symptoms such as pain in the lower or upper back, abdomen and legs, and numbness and weakness in the legs.
Spine tumors occur due to uncontrolled cell growth inside the spinal column, explains Cleveland Clinic. Patients with spine tumors typically have back pain that does not improve with rest. Patients may also experience sciatica, fever, spinal deformity, numbness and partial paralysis. If left untreated, these symptoms worsen over time.
Fibromyalgia is a syndrome that causes tenderness, widespread pain and fatigue, states the National Institute of Arthritis and Musculoskeletal and Skin Diseases. The syndrome is not a true form of arthritis as it does not cause damage to tissues such as the joints. However, patients with fibromyalgia experience similar symptoms to arthritis including significant pain that affects a person's ability to perform everyday tasks. Other symptoms of fibromyalgia include headaches, temperature sensitivity and restless legs syndrome.