context: The spine, or backbone, is made up of a column of 33 bones and tissue extending from the skull to the pelvis. These bones, or vertebrae, enclose and protect a cylinder of nerve tissues known as the spinal cord. Between each one of the vertebra is an intervertebral disk, or band of cartilage serving as a shock absorber between the vertebrae. The types of vertebrae are: Cervical vertebrae: the seven vertebrae forming the upper part of the spine Thoracic vertebrae: the 12 bones between the neck and the lower back Lumbar vertebrae: the five largest and strongest vertebrae located in the lower back between the chest and hips The sacrum and coccyx are the bones at the base of the spine. The sacrum is made up of five vertebrae fused together, while the coccyx (tailbone) is formed from four fused vertebrae. The causes of back pain can be complex. Some causes of back pain include accidents, muscle strains, and sports injuries. In addition to performing a complete history and physical exam for your back pain, your doctor may suggest one of the following diagnostic studies: X-rays, which can be used to provide detail of the bone structures in the spine and to check for instability (such as spondylolisthesis, see below), tumors, and fractures CT scans, which can identify specific conditions, such as a herniated disc or spinal stenosis MRI scans, which can provide details about the backs' discs and nerve roots. MRI scans are most commonly used for pre-surgical planning A number of other imaging and electrical studies may also be used to identify back problems, and some injections are used for diagnostic purposes as well as for pain relief. Two main types of back injury include: Spondylolisthesis: This is a slipping of vertebra that occurs, in most cases, at the base of the spine. Spondylolysis, which is a defect or fracture of one or both wing-shaped parts of a vertebra, result in this vertebral slipping backward, forward, or over a bone below. Cervical Radiculopathy: Cervical radiculopathy is the damage or disturbance of nerve function that results if one of the nerve roots near the cervical vertebrae is compressed. Damage to nerve roots in the cervical area can cause pain, weakness, and the loss of sensation in the neck, arms, or shoulders, depending on where the damaged roots are located. There are many causes for spondylolithesis. A vertebra might be defective from the time a person is born, or a vertebra may be broken by trauma or a stress fracture. In addition, vertebrae can be broken down by infection or disease. Symptoms of spondylolithesis may include: Lower back pain Muscle tightness and stiffness Pain in the buttocks Pain radiating down the legs (due to pressure on nerve roots) Muscle weakness Spondylolisthesis is treated with the strengthening of supportive abdominal and back muscles through physical therapy. Acetaminophen or nonsteroidal anti-inflammatory medicines, such as ketoprofen ( Frotek), ibuprofen ( Motrin, Advil), and naproxen ( Aleve, Naprosyn) may help with pain. Epidural steroid injections may also be effective. For patients who continue to have severe pain and disability despite these treatments, there are options such as decompressive laminectomy, a procedure in which the spinal canal is widened (to provide more room for nerves and a spinal fusion is performed to stabilize the spinal cord), with or without surgical fusion (arthrodesis) of the vertebra, or the use of an implanted device to stabilize the vertebrae in the lower back while permitting more normal movement. In cervical radiculopathy, damage can occur as a result of pressure from material from a ruptured disc, degenerative changes in bones, arthritis, or other injuries that put pressure on the nerve roots. In older people, normal degenerative changes in the discs can cause pressure on nerve roots. In younger people, cervical radiculopathy tends to be the result of a ruptured disc. This disc material then compresses the nerve root, causing pain. The main symptom of cervical radiculopathy is pain that spreads into the arm, neck, chest, and/or shoulders. A person with radiculopathy may experience muscle weakness and/or numbness or tingling in fingers or hands. Other symptoms may include lack of coordination, especially in the hands. Cervical radiculopathy may be treated with a combination of pain medications such as acetaminophen ( Tylenol), or nonsteroidal pain medication such as ibuprofen ( Advil, Motrin), ketoprofen ( Frotek), naproxen ( Aleve, Naprosyn), and physical therapy. Steroids may be prescribed either orally or injected epidurally (into the epidural space that surrounds the spinal cord). Physical therapy might include gentle cervical traction and mobilization, exercises, and other modalities to reduce pain. If significant compression on the nerve exists to the extent that motor weakness results, surgery may be necessary to relieve the pressure.