|Lumbar disc disorder with myelopathy refers to a disorder of the lumbar spine that results in compression of the lowest portion of the spinal cord (conus medullaris). Myelopathy is an inclusive term referring to any disorder of the spinal cord. The lumbar region specifies the lower portion of the spine from the mid- to lower back between the thoracic spine of the upper back and sacral region at the base of the spine. The lumbar spine contains five vertebrae (L1-L5).|
Examples of myelopathy include: carcinomatous myelopathy (spinal cord degeneration associated with cancer); compressive myelopathy (spinal cord changes from the pressure of hematomas, stenosis [narrowing], or masses); radiation myelopathy (spinal cord destruction from radiation sources such as x-ray therapy). When spinal cord destruction is caused by a complication of disease, the specific myelopathy signifies that origin. (e.g., diabetic myelopathy).
Lumbar disc disorders most commonly include lumbar disc disease (a chronic, degenerative condition of the cushion-like discs between the lumbar vertebrae) and disc displacement (an abnormal protrusion or herniation of a disc that separates the vertebrae in the lower back or lumbar area of the spine). The most common areas of disc herniation are between L4 and L5 and between L5 and the first sacral vertebra (S1). Since the spinal cord ends in the middle back at L1 or at the L1-L2 vertebrae (varies), only herniations of L1-L2 discs can cause spinal cord compression or myelopathy. Disc disorders with myelopathy occurring between lumbar vertebrae L3 to L5 are rare. Herniations of L2-L3 through L5-S1 can cause radiculopathy (compression of one spinal nerve root) or cauda equina syndrome (many spinal nerve roots compressed).
For L1-L2 herniations with myelopathy, please refer to Thoracic Disc Disorder with Myelopathy, since L1-L2 herniations behave like lower thoracic herniations. For L2-L3 through L5-S1 herniations, please refer to the topic Displacement, Lumbar Intervertebral Disc Without Myelopathy.
Risk: The most common risk factor for lumbar disc disorder with myelopathy disc is age-related disc degeneration in the presence of stenosis. Other risk factors include obesity, diabetes, and cigarette smoking. Genetic predisposition has also been suggested as a cause (Patel).
Incidence and Prevalence: The estimated lifetime incidence of lower back pain is 60-90% with annual incidence estimated at 5% (Patel). The precise incidence of lumbar disc degeneration and disc displacement with myelopathy is unknown. However, the National Center for Health Statistics reports that low back pain accounts for 13 million visits to doctors each year, with 14.3% of all new doctor visits attributed to lower back pain; it is also the most frequent reason given for lost productivity in the US (Patel).
Source: Medical Disability Advisor
CitedPatel, Rajeev K., and Curtis W. Slipman. "Lumbar Degenerative Disc Disease." eMedicine. Eds. J. Michael Wieting, et al. 18 Jan. 2007. Medscape. 23 Mar. 2009 <http://emedicine.medscape.com/article/309767-overview>.
GeneralBerger, Joseph, and Stephen Ryan. "Medical Myelopathies." The Spine. Eds. H. N. Herkowitz, et al. Philadelphia: W.B. Saunders, 1999. 1413-1428.
Williams, Keith D., and Ashley L. Park. "Lumbar Disc Disease." Campbell's Operative Orthopaedics. Eds. S. Terry Canale and James H. Beatty. 11th ed. Philadelphia: Mosby Elsevier, 2007. 2199-2216. MD Consult. Elsevier, Inc. 19 Jan. 2009 <http://home.mdconsult.com>.
Source: Medical Disability Advisor