Our posts in this series have been reviewing spine-related musculoskeletal conditions that are frequently seen in dentists and surgeons. In this post, we will be looking at disc bulge, disc herniation, and disc protrusion.
Disc Bulge, Disc Herniation, and Disc Protrusion
- Disc Bulge: Protrusion of a spinal disc outside the vertebral body that has not fully ruptured through the disc membrane, known as the annulus.
- Disc Herniation: Protrusion of a spinal disc outside the vertebral body that has ruptured through the annulus, exposing a portion of the nucleus – the gel-like center of the disc.
- Disc Protrusion: A general term to describe any type of disc bulge or herniation, in which a portion of the disc protrudes beyond the vertebral body.
Overview: A number of terms are used to describe spinal disc pathology and the associated symptoms. To complicate matters further, there is not a clear consensus among medical professionals about the precise meaning of each term.
There are thirty-three vertebrae in the vertebral column of the human spine, twenty-four of which articulate and move. Between each of the vertebrae in the three articulating sections of the spine – the cervical, thoracic, and lumbar spine – there is an intervertebral disc. Each disc, composed of soft jelly-like center (nucleus) surrounded by a capsule of connective tissue (annulus), provides shock absorption and flexibility within the spine. When the protrusion puts pressure on the spinal cord or a nerve root, it can lead to a wide range of symptoms.
Symptoms: Symptoms will vary based on the location of the disc:
- Lumbar: Pain radiating down the leg (sciatica) is the most common symptom associated with a lumbar disc herniation. Weakness in the foot and difficulty when raising the big toe (foot drop) and numbness/pain on the top of the foot are also prevalent.
- Cervical: Pain, weakness, numbness, and tingling in the shoulder, arm, or hand depending on the location of the herniated disc.
Causes: Disc bulges are often the result of the normal process of aging, and by themselves may not cause any recognizable symptoms. Bad posture associated with frequent sitting or standing and occupational hazards such as repetitive bending or standing can accelerate the formation of disc bulges.
Disc herniation is often a progression in severity from a disc bulge. As discs wear down over time, they may degenerate and lose some of their water content. This condition, known as Degenerative Disc Disease, is discussed in greater detail below. As discs degenerate and degrade, they become more flexible and the annulus may be more susceptible to tearing or rupturing. Disc herniation can also be caused by traumatic, acute injuries such as a hard fall or blow to the back.
Diagnosis: Diagnosis of a herniated or bulging disc typically begins with a physical exam that tests the patient’s reflexes, muscle strength, walking ability, and sensory perception (light touches, pin pricks, etc.). If a protrusion is indicated by the physical test, imaging may be ordered in the form of X-rays, MRIs, CT scans, and/or Myelograms.
Treatment: Non-invasive treatment may include heat therapy, exercise, physical therapy, chiropractic treatment, therapeutic ultrasound, and medication. Epidural steroid injections may be considered as an intermediate treatment. For more severe cases, a microdiscectomy may be performed, typically in an outpatient setting. In this procedure, a small portion of bone and/or disc material is removed to relieve pressure on the affected nerve root.
Our next post will discuss degenerative disc disease.
These posts are for informative purposes only and should not be used as a substitute for consultation with and diagnosis by a medical professional. If you are experiencing any of the symptoms described below and have yet to consult with a doctor, do not use this resource to self-diagnose. Please contact your doctor immediately and schedule an appointment to be evaluated for your symptoms.
1. Spine-health, https://www.spine-health.com/.
2. Mayo Clinic, http://www.mayoclinic.org/.
3. The Neurological Institute of New York,
4. John Hopkins Medicine, http://www.hopkinsmedicine.org/.
5. WebMD, http://www.webmd.com/.