Lumbosacral Discogenic Pain Syndrome Clinical Presentation
- Author: Robert E Windsor, MD, FAAPMR, FAAEM, FAAPM; Chief Editor: Craig C Young, MD more...
The history and physical examination findings of the athlete and nonathlete with discogenic or radiculopathic pain are similar.
- Discogenic pain typically increases with sitting, flexion, coughing, sneezing, or activities that increase intradiscal pressure.
- Common features of radiculopathy are leg pain in a dermatomal distribution, exacerbation of pain with a sitting position, and amelioration of pain during standing or ambulation. It is typically a flexion, rotation, or combined flexion-rotation injury.
Physical examination does not yield significant information when dealing with internal disc derangement. Physical examination of the lumbar spine evaluating for discogenic pain should focus on a mechanical and neurologic examination in an attempt to identify the likely source of back pain (ie, mechanical, neurologic, or discogenic).
Causes of internal disc derangement (IDD) usually involve a series of traumatic events ranging in significance from minor disc injuries to more severe types of injuries. The accumulation of the injuries is generally believed to yield the degenerative nature of the annulus, and the lack of integrity is believed to allow water and protein molecules to escape the confines of the nucleus.
The difference between an asymptomatic degenerative disc and one that hurts has been in question. The nucleus pulposus has no nerve supply; however, the outer third of the annulus is innervated. It receives supply from both the gray ramus laterally and anteriorly and from the sinuvertebral nerve posterior and posterolaterally. The current model holds that in some manner, these annular sensory nerves become sensitized, and any turbulence, such as that caused by twisting or weight-bearing, provokes pain. One possibility is that the nuclear proteins become exposed to the system circulation, allowing an autoimmune reaction to the protein and an intense inflammatory process inside the disc.
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