A disc is a gelatinous structure positioned between the bony vertebrae of the spine. The disc allows for movement between segments of the spine and also provides shock absorption between the rigid bones of the spine. This gelatinous material is usually contained by a fibrous border. Occasionally, a disc fragment can protrude through this fibrous border and protrude into the spinal canal or neural foramina. This disk herniation may produce a “radiculopathy” from compression of a nerve (see radiculopathy definition in the Cervical and Lumbar Disc Disease section), or it may cause neurologic symptoms by compressing the spinal cord.
The symptoms of a disk herniation may be characterized by low back pain with associated buttock, thigh, or leg pain if the herniation is situated in the lumbar spine. If the disc herniation is situated in the neck, it may produce neck pain with associated shoulder blade or arm pain. Disc herniations may also produce symptoms of numbness, tingling, or weakness. In drastic cases, disc herniations can cause bowel or bladder symptoms. In cases where the disc herniation pushes on the spinal cord, it may cause symptoms of myelopathy – balance issues, coordination issues, clumsiness of hands, and/or bowel/bladder changes.
The diagnosis of a disc herniation is usually made by listening to a patient’s symptoms, examining the patient, and correlating the symptoms and exam findings to imaging. The most common imaging modality for demonstrating a disc herniation is an MRI, which allows for visualization of soft tissues including discs and nerves, structures that an x-ray does not demonstrate. Occasionally, if a patient cannot obtain an MRI secondary to metal implants, or if an MRI is not interpretable, a CT myelogram may be ordered. This study requires injection of contrast dye into the spinal canal, followed by a CT scan, to visualize the skeletal anatomy and the neural structures.
Most disc herniations can be managed non-surgically, as the resultant pain is self-limited, which means it will usually resolve with observation and antiinflammatory medication. In some cases, however, further treatments are required including physical therapy, anti-inflammatory injections (epidural steroid injections), or even surgery in the case of relentless pain, weakness or clumsiness.