Our spine is made of a series of blocks with are stacked vertically. The blocks are called vertebrae. Between each vertebra is a cushion, called a disc. The discs are made of cartilage and have high water content. As we age, the water content in the disc decreases making the disc less compressible and elastic.
The spinal cord is located in a canal that runs through the vertebra. Nerves exit from between the vertebrae and travel into the arms, legs and torso. As the disc gradually dries, if may flatten or bulge from its original location. Nerves may no longer have adequate space (they may be pinched against protruded disc tisuue or against the bone of a the spine (the vertebrae).
Degenerative Disc Disease may begin early in life (the 20’s-30’s) due to trauma. More usually, it occurs later (50’s or older) due to a combination of aging of the discs and the effects of many small episodes of trauma to the spine.
Symptoms include pain in the area of the spine, which is involved, (neck-cervical, midback (thoracic) or low back (lumbar). If nerves in the neck are involved there may be numbness or weakness of the arms and hands. If the low back is involved, the symptoms will be the legs. Pain and numbness in the legs is commonly called “Sciatica”.
If the spinal canal is narrowed, the legs may tire or feel heavy with walking. This is called “Spinal Stenosis”.
Testing includes a carefully performed history and physical examination. A skillful physician will recognize symptoms and know when it is necessary to proceed with testing. An x-ray of the spine is the initial test for the evaluation of back pain. A blood test to exclude a serious medical condition called Multiple Myeloma should be obtained. If there is a personal history of cancer a bone scan, MRI or PET scans are use to exclude cancer recurrence. These imaging studies are noninvasive and reveal the anatomy of the spine. A myelogram with CAT scan is the most definitive of the testing and is most commonly ordered as a pre-surgical test. Nerve conduction studies may help to locate nerve entrapment.
Treatment varies according to the severity of the problems. The mildest, and a very effective treatment is rest. Physical Therapy, including ice, heat, ultrasound, message and eventually strengthening and stretching of the “core” (muscles of the abdomen and spine). This strengthening and stretching is important in preventing recurrence. Learning proper body mechanics to prevent re-injury is essential. Lifting with the knees, keeping the back straight. Injury often occurs with the first 15 degrees of forward bending of the spine.
Steroid injection into the painful areas along the spine, anti-inflammatory or pain medications and Epidural Steroid Injection are used when symptoms persist.
Surgery is needed when there is weakness of leg or arms muscles or unremitting pain due to nerve entrapment Surgery is sometimes recommended for pain that does not respond to more conservative treatment.
Most of us develop Degenerative Disc Disease as we age. Usually we are only intermittently bothered by symptoms. The presence of an abnormal disc is not a reason for surgery. Back pain usually resolves with time.