The upper back is the region below the cervical spine (neck) and above the low back (lumbar spine). The upper back is called the thoracic spine,  Poor posture in general, or working at the computer for a long time without taking a break to walk around and stretch can contribute to upper back. Both muscle fatigue and muscle strain, which often result from poor posture, can trigger the pain. In most cases, upper back pain is not a cause for worry; however, it can be uncomfortable, painful, and inconvenient. Your doctor may prescribe medications, such as a muscle relaxant or perform trigger point injections to help break up muscle spasms. He may also recommend physical therapy to increase flexibility, mobility and relieve pain Consult orthopedic doctor.