Low Back Pain in the Elderly- My Aging Aching Back
Background of Back Pain in the Elderly
Intervertebral disc degeneration occurs with aging which causes a progressive deterioration of the adjacent bone, muscles, zygapophyseal (facet) joints and ligaments. It is difficult to differentiate normal aging from pathological processes. Genetics accounts for 50-70% of disc degeneration variability
- Up to 75% of the total axial compressive load is carried by the anterior column
- The intervertebral disc can withstand 2.8 to 13.0kN of compressive force
- Intradiscal proteoglycan content progressively declines with advancing age
- Vertebral endplate permeability decreases beginning in the second decade of life
- Changes first affect the endplate, followed by the nucleus pulposus and the annulus fibrosis over several spinal levels
- Calcified nucleus pulposus herniation through the endplate is called a Schmorl’s node
- Degeneration of the normally avascular intervertebral disc allows blood vessels and nociceptive fibers to penetrate the disc introducing inflammatory mediators into the previously avascular space.
- The degenerative cascade describes the loss of hydrostatic pressure within the nucleus pulposus resulting in increased compressive loads on the annulus fibrosis and zygapophyseal (facet) joints.
- Intervertebral disc injuries never fully heal.
- Osteophytes increase the load bearing surface area.
- The aging ligamentum flavum looses elastin content causing anterior bulging that can contribute to central spinal stenosis.
- Loss of dorsal extensor muscle and the abdominal flexors muscle equilibrium
- genetic inheritance
- high or repetitive mechanical loading
- Ranges from painless progression to severe back pain
- Progressive weakness
- Loss of flexibility
- Narrowing in adult intervertebral discs occurs at a rate of 3% per year.
- The majority of acute disc herniations occur between the ages of 30 and 50 years old.
- 90% of lumbar discs demonstrate degeneration by the fifth decade of life.
- Differential diagnosis includes fracture, infection, neoplasm and stenosis
- X-rays demonstrate degenerative changes in 90% of patients.
- MRI can identify disc degeneration in 35% of healthy volunteers.
- Larger disc herniations seen on initial imaging correspond with greater resolution of the herniation in two to three years.
- No correlation with pain and disc signal intensity on MRI
This sagittal lumbar MRI demonstrates decreased T2 signal and disc space narrowing and disc bulging at multiple levels demonstrating more advanced degenerative disc disease.
- Nonsteroidal anti-inflammatory medications such as naprosyn or ibuprofen
- Acupuncture has been described to be helpful
- Lumbar stabilization focuses on stabilizing the painful pathologic region with muscular development and movement patterns
- Flexion or extension bias in stretching and strengthening
- Mechanical evaluation to determine a direction of preference
- Heat, cold, ultrasound, and transcutaneous electrical nerve stimulation have been used for symptomatic relief of pain and muscle spasms.
- Trigger point injections
- Epidural steroid injections for symptoms related to radiculitis, radiculopathy or stenosis
- Surgical decompression and/or fusion for unrelenting pain
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- Panagos A. Rehabilitation Medicine Quick Reference-Spine (ed. Buschbacher R.M.) New York: Demos Publishing; 2010. p. 2-3.
- Kirkaldy-Willis WH, Wedge JH, Yong-Hing K, Reilly J. Pathology and pathogenesis of lumbar spondylosis and stenosis. Spine. 1978 Dec;3(4):319-28.