Degenerative Disc Disease
Definition, Causes and Stages
The discs are shock absorbers between the vertebrae, designed to help the back stay flexible while resisting forces in many different planes of motion. Each disc has two parts, anulus fibrosus (firm, tough outer layer) and nucleus pulposus (a softer core).
Disc degeneration, is a condition in which the disc loses its normal water content and its ability to absorb weight and shock during motion. Disc degeneration involves structural disruption and cell-mediated changes in composition.
Mechanical, traumatic, nutritional, and genetic factors may all play a role in the cascade of disc degeneration. Disc degenerative changes are part of the normal aging process, in that everyone experiences it, but only some of the discs with these changes ever produce symptoms of discomfort. In first three decades of life, our discs are well hydrated and serve as a cushion for the vertebrae.
As we age, discs become dehydrated, and loose height as well as suppleness. A dehydrated disc is more prone to trauma, disc tear and herniation even with normal daily activity. With loss of height, a herniation may lead to nerve and spinal cord impingement which can cause pain. A tare in a the anulus fibrosis (firm, tough outer layer) may also lead to spine pain.
Degrees of disc degeneration: Dehydrated disc with normal height, Dehydrated disc with loss of height, Dehydrated disc with annular tear, Disc desiccations (mid, Moderate, sever), Disc herniation
Stages of Disc Herniation: Disc bulge (usually not symptomatic unless it has an annular tear), Disc protrusion, Disc Extrusion, Disc sequestration (separated fragment).
Acute or chronic low back pain, neck pain, sciatica (lumbar radiculopathy) or cervical radiculopathy are the main complaints of an individual with symptomatic DDD (degenerative disc disease). Spinal pain associated with lifting, bending, coughing, running and spine movement could be related to DDD. Also, spine pain that travels down one leg or one arm may be due to DDD and subsequent herniation.
The symptoms of disc degeneration are among the leading causes of functional loss in both sexes, and are a common source of chronic disability in the working years. The good news: Symptoms don't typically progress. A diagnosis in your 30s or 40s doesn't mean you'll be symptomatic for life. Taking steps to manage symptoms and keep your spine and back healthy can help you stay mobile and active throughout your life.
Degenerative disc disease diagnosis is based on history, physical examination as well his symptoms and the circumstance where the pain started. If the first episode is acute and severe, patients often go to the emergency room. A clinical diagnosis is made based on x-rays (disc space narrowing, end plate changes, spurring), and physical examination. If there is no progressive neurological loss, further care is often deferred to the primary care physician and/or specialist in an outpatient setting. A spine specialist will examine the patient and determine proper workup. A thorough physical examination is performed by the spine specialist, which includes range of motion examination, sensory testing, strength testing and evaluation of reflexes. If there are alarming signs of spinal cord compression, recommendation for a further workup is made.
The most accurate clinical test to identify DDD is an MRI. He can show disc space narrowing, herniation of the disc and any impingement or spinal stenosis. Some patients are unable to have an MRI, in which case a CT will help make a diagnosis. To identify a painful disc, a discogram test may be performed.
Prevention is the best medicine. A healthy lifestyle not only improves symptoms, but it can actually slow the degenerative process. General recommendations include exercise (aerobic activities, core strengthening and stretching, maintain a healthy weight, smoking cessation, increase water intake, and limit alcohol intake.
To treat, if there are no alarming neurological deficits, simple x-rays, 6-8 weeks of physical therapy, short course of prednisone taper, spine manipulation, soft tissue treatments along with use of nonsteroidal anti-inflammatory and muscle relaxants are recommended. In the acute phase, sometimes mild opioid medication is prescribed to help with sleep and function (no indication for long-term use). In most cases, conservative treatment results in substantial improvement of symptoms.
After physical therapy treatment, the patient is re-examined to evaluate for any residual deficits or symptoms. If the pain subsides and function fully recovers, the patient is discharged with a recommendation to continue a home exercise program and observe correct ergonomics. In some patients, the pain and dysfunction are not managed on oral medications or does not improve with physical therapy. In such cases, targeted steroid injections epidural injection or selective nerve root injection (transforaminal injection) can help reduce the inflammation in the nerve root and help with the recovery.
Although DDD is detected on an MRI, it is not always the cause of spinal pain. In individuals with DDD, facet osteoarthritis is prevalent due to changes in spine mechanics. Facet osteoarthritis in fact may be the source of spinal pain which could be treated by a facet injection and radiofrequency ablation treatment.
Regenerative treatments such as, PRP injection (platelet Rich plasma), stem cell injections as well as other biologics can be injected into the painful disc with the goal of disc regeneration to offset the aging process. They are FDA approved options, and are being actively studied for efficacy and safety.
Spinal injections may last several weeks to several months. If the symptoms return, such treatment could be repeated.
Careful risk assessment should be done by the primary care physician, spine surgeon and the patient before considering surgery.
DDD with radiculopathy has a better surgical outcome as compare to DDD with only back pain. There are several types of spine surgery that can address DDD.
• Decompression – removal of a displaced disc or overgrown bone to free pinched nerves.
• Fusion – building a bone bridge to provide stability and prevent painful motion.
• Deformity correction to address abnormal curvatures.
• Placement of implants, such as spacers, artificial discs and nerve stimulators.
Surgery takes a few hours to complete, with a short course of inpatient hospitalization and a few weeks of outpatient rehabilitation after discharge from the hospital. Fusion has a longer course of recovery.
Exercises for DDD - http://www.spine-health.com/video/lumbar-degenerative-disc-disease-video