Cervical disc herniation is a condition wherein the cartilaginous discs that separate the vertebrae in the neck become weakened and degenerate. The tough outer ring of the disc is eroded so severely that the inner core of the disc, called the nucleus pulposus, protrudes through it. The nucleus pulposus can bulge into the spinal canal and compress the spinal cord or its nerve roots. Symptoms can vary depending on which segment of the cervical spine is affected.
Pain Management
Dr. John P. Revord, a pain medicine and management physician with NeuroSpine Center of Wisconsin, states that herniation of the disc between the fourth and fifth cervical vertebrae can cause shoulder pain. Herniation of the disc between the fifth and sixth cervical vertebrae causes pain that can radiate down the arm and into the thumb. Pain from herniation of the disc between the sixth and seventh vertebrae shoots along the triceps muscle and into the middle finger. The seventh and last cervical vertebra, called C7, is followed by the first thoracic vertebrae, T1. Herniation of the disc between these two segments can cause pain down the arm and into the pinky. The National Institutes of Health notes that pain associated with disc herniation typically has a slow onset, and can be exacerbated by postural changes or by actions that increase pressure within the torso, such as sneezing or coughing.
Numbness or Paresthesia
Paresthesia is a tingly, pins-and-needles sensation often associated with nerve damage. Numbness can occur when sensory nerve impulses are interrupted due to impingement by a herniated disc or bone spur. Both of these sensory deficits have been observed in patients with cervical disc herniation. The distribution of these sensory deficits follows the same pattern as the pain symptoms associated with disc herniation. For example, paresthesia from the triceps through the middle finger can indicate herniation of the disc between C6 and C7, according to Revord.
Muscle Weakness
As with pain, muscle weakness corresponds to specific nerves that can be impinged upon by the intervertebral discs with which they are associated. A herniation of the C4-C5 disc can weaken the deltoid muscle, says Revord. The disc between C5 and C6 can impinge on the muscles that supply the biceps. Weakness of the muscles in the hand can be caused by herniation of the disc between the C7 and T1 vertebrae can affect a person's ability to grip an object, while a C6-C7 herniation can make it difficult to release one.
