Degenerative disc disease

Degenerative disc disease
Classification and external resources
Degenerated disc, C5-C6 with osteophytes
ICD-10	M51.3
ICD-9	722.6
DiseasesDB	6861

Degeneration of the intervertebral disc, often called "degenerative disc disease" (DDD) of the spine, is a condition that can be painful and can greatly affect the quality of one's life. While disc degeneration is a normal part of aging and for most people is not a problem, for certain individuals a degenerated disc can cause severe constant chronic pain.

Symptoms

With symptomatic degenerative disc disease, chronic low back pain sometimes radiates to the hips, or there is pain in the buttocks or thighs while walking; sporadic tingling or weakness through the knees may also be evident. Similar pain may be felt or may increase while sitting, bending, lifting, and twisting. Chronic neck pain can also be caused in the upper spine, with pain radiating to the shoulders, arms and hands. Neck pain may cause interrupted blood supply to the brain resulting in headaches, vertigo and worsened cognitive abilities and memory.

Understanding disc pain

After an injury, some discs become painful because of inflammation. Some people have nerve endings that penetrate more deeply into the annulus fibrosus (outer layer of the disc) than others, making discs more susceptible to becoming a source of pain. The scientific community^[who?] has the opinion that the healing process involved in the repair of trauma to the outer annulus results in the innervation of the resultant scar tissue, and subsequent pain in the disc, as these nerves become inflamed by nucleus pulposus material. Degenerative disc disease can lead to a chronic debilitating condition and can have a serious negative impact on a person's quality of life. When pain from degenerative disc disease is severe, traditional nonoperative treatment is often ineffective.

Pathologic changes

Micrograph of a fragment of a resected degenerative vertebral disc, showing degenerative fibrocartilage and clusters of chondrocytes. HPS stain.

Degenerative discs typically show degenerative fibrocartilage and clusters of chondrocytes, suggestive of repair. Inflammation may or may not be present. Histologic examination of disc fragments resected for presumed DDD is routine to exclude malignancy.

Fibrocartilage replaces the gelatinous mucoid material of the nucleus pulposus as the disc changes with age. There may be splits in the annulus fibrosis, permitting herniation of elements of nucleus pulposus. There may also be shrinkage of the nucleus pulposus that produces prolapse or folding of the annulus with secondary osteophyte formation at the margins of the adjacent vertebral body. The pathologic findings in DDD include protrusion, spondylolysis, and/or subluxation of vertebrae (sponylolisthesis) and spinal stenosis.

Treatment options

Often, degenerative disc disease can be successfully treated without surgery. One or a combination of treatments such as physical therapy, chiropractic manipulative therapy (CMT) and other chiropractic treatments, osteopathic manipulation, anti-inflammatory medications such as nonsteroidal anti-inflammatory drugs, traction, or spinal injections often provide adequate relief of these troubling symptoms.

Surgery may be recommended if the conservative treatment options do not provide relief within two to three months. If leg or back pain limits normal activity, if there is weakness or numbness in the legs, if it is difficult to walk or stand, or if medication or physical therapy are ineffective, surgery may be necessary, most often spinal fusion. There are many surgical options for the treatment of degenerative disc disease. The most common surgical treatments include:^[1]

• Anterior cervical discectomy and fusion: A procedure that reaches the cervical spine (neck) through a small incision in the front of the neck. The intervertebral disc is removed and replaced with a small plug of bone or other graft substitute, and in time, that will fuse the vertebrae.

• Cervical corpectomy: A procedure that removes a portion of the vertebra and adjacent intervertebral discs to allow for decompression of the cervical spinal cord and spinal nerves. A bone graft, and in some cases a metal plate and screws, is used to stabilize the spine.

• Dynamic Stabilisation: Following a discectomy, a stabilisation implant is implanted with a 'dynamic' component. This can be with the use Pedicle screws (such as Dynesys or a flexable rod) or an interspinous spacer with bands (such as a Wallis ligament). These devices off load pressure from the disc by rerouting pressure through the posterior part of the spinal column. Like a fusion, these implants allow maintain mobility to the segent by allowing flexion and extension.

• Facetectomy: A procedure that removes a part of the facet to increase the space.

• Foraminotomy: A procedure that enlarges the vertebral foramen to increase the size of the nerve pathway. This surgery can be done alone or with a laminotomy.

• Intervertebral disc annuloplasty (IDET): A procedure wherein the disc is heated to 90°C for 15 minutes in an effort to seal the disc and perhaps deaden nerves irritated by the degeneration.

• Intervertebral disc arthroplasty: also called Artificial Disc Replacement (ADR), or Total Disc Replacement (TDR), is a type of arthroplasty. It is a surgical procedure in which degenerated intervertebral discs in the spinal column are replaced with artificial ones in the lumbar (lower) or cervical (upper) spine.

• Laminoplasty: A procedure that reaches the cervical spine from the back of the neck. The spinal canal is then reconstructed to make more room for the spinal cord.

• Laminotomy: A procedure that removes only a small portion of the lamina to relieve pressure on the nerve roots.

• Micro-discectomy: A procedure that removes a disc through a very small incision using a microscope.

• Percutaneous disc decompression: A procedure that reduces or eliminates a small portion of the bulging disc through a needle inserted into the disc, minimally invasive.

• Percutaneous Laser Disc-Decompression (PLDD): Based on this small study population, it can be concluded that PLDD may be an effective treatment for disco-genic back pain with minimal natural recurrence.^[2]

• Spinal decompression: A non-invasive procedure that enlarges the Intra Vertebral Foramen (IVF) by aiding in the rehydration of the spinal discs.

• Spinal laminectomy: A procedure for treating spinal stenosis by relieving pressure on the spinal cord. A part of the lamina is removed or trimmed to widen the spinal canal and create more space for the spinal nerves.

New treatments are emerging that are still in the beginning clinical trial phases. Glucosamine injections are thought to offer some pain relief for degenerative discs at best, and at worst, do nothing while also not affecting more aggressive treatment options. In the US artificial disc replacement is viewed cautiously as a possible alternative to fusion in carefully selected patients, yet it is widely used in a broader range of cases in Europe, where multi-level disc replacement of the cervical and lumbar spine is common..^[3] Adult stem cell therapies for disc regeneration are in their infancy. Investigation into mesenchymal stem cell therapy knife-less fusion of vertebrae in the United States began in 2006.^[4]

See also

• Failed back syndrome

References

1. ^ "Degenerative Disc Disease - When Surgery Is Needed". http://www.spineuniverse.com/displayarticle.php/article4029.html. Retrieved 2007-06-26. 
2. ^ Black W, Fejos AS, Choy DS (October 2004). "Percutaneous laser disc decompression in the treatment of discogenic back pain". Photomed Laser Surg 22 (5): 431–3. doi:10.1089/pho.2004.22.431. PMID 15671718. 
3. ^ "Spinal Kinetics M6 Disc Replacement". Stenum Hospital, Germany. http://www.stenumhospital.com/technology/prestige.asp. Retrieved 2010-02-26. 
4. ^ "Mesoblast files spinal fusion IND". Australian Life Scientist. 2006-11-27. http://www.biotechnews.com.au/index.php/id;140193681. Retrieved 2009-02-16.