History and Epidemiology

Facet hypertrophy is a common condition that occurs when the facet joints in the spine become enlarged. The facet joints are synovial joints in the spine where two vertebrae come into contact. They help to stabilize the spine during bending and twisting motions.

Facet hypertrophy can be unilateral or bilateral and can happen for a variety of reasons, including injury, arthritis, or simply the aging process.

Facet hypertrophy can cause a number of problems, including pain, stiffness, and reduced range of motion.1 Facet arthrosis, or degeneration, has been found in 100% of cadavers aged 60 and over.2 The L4-L5 level had the highest prevalence and degree of arthrosis.2

The prevalence of facet joint involvement in low back pain has been found to be 15% to 45%.3 Arthrosis of the facet joints may begin before age 30 and may affect men more than women.2

Etiology and Risk Factors

Spondylosis, or degeneration of the spine, is the most common cause of facet joint disease. Osteoarthritis, or degeneration that is due to natural wear and tear, is a process that involves cytokines and proteolytic enzymes. Other causes of facet hypertrophy can include trauma caused by car accidents, sports injuries, or falls.1

Inflammation of the synovium may also contribute to facet hypertrophy. Conditions that cause inflammation in the synovial fluid include rheumatoid arthritis and ankylosing spondylitis. Spondylolisthesis, a condition that involves instability of the spine, may also contribute to facet hypertrophy. With this problem, subluxation of the facet joints may occur.

Risk factors for facet arthritis include:4

  • advanced age
  • degenerative disc disease
  • prior history of trauma or injury
  • history of bad posture
  • family history of degenerative arthritis

Facet Hypertrophy Prognosis

Facet joint hypertrophy is a chronic, painful disease that progresses with age.1 It’s important to convey to patients that there is no cure, but treatments may help to decrease pain. Maintaining an active lifestyle and healthy weight are keys to preventing further stress on the joints.

Facet Hypertrophy Diagnosis & Presentation

Patients may present with chronic neck or back pain. It may be described as worse in the morning or after periods of inactivity. Pain may be worse with rotation or extension of the spine, and palpation of the facet joints often results in pain. Pain may also radiate to the buttocks, groin, and thighs.

The following may be performed during a physical exam to aid in diagnosis:

  • Kemp’s maneuver (The patient, with aid of the examiner, extends and rotates the spine to reproduce pain.)
  • lateral rotation
  • lateral bending
  • back extension

Patients may undergo imaging studies such as X-ray, CT, or MRI. Facet joint hypertrophy may be found along with narrowing and calcification of the joint space. Breakdown of cartilage and inflammation may also be found. Ligamentum flavum hypertrophy may occur as well as bone spurs and increased subchondral bone volume. The ligamentum flavum helps maintain upright posture. Elasticity may decrease with age, leading to disc injury.

Because radiologic changes may also be seen in patients who are asymptomatic, further testing is necessary to confirm a diagnosis of facet hypertrophy. Medial branch blocks should be performed to confirm that pain is due to the facet joints. Two diagnostic medial branch blocks should be performed on two separate days at two or more levels of the spine. If a positive response is detected two times, a diagnosis of facet hypertrophy may be confirmed.

Differential Diagnosis

It is vital to rule out other causes of neck and back pain when diagnosing facet hypertrophy. Differential diagnoses include:1

  • rheumatoid arthritis
  • osteophytes (bone spurs)
  • myofascial pain
  • herniated discs
  • compression fractures
  • lumbar radiculopathy
  • osteoarthritis of the hip
  • sciatica
  • impingement of the sacroiliac joint
  • ganglion and synovial cysts
  • ankylosing spondylitis (This type of arthritis can cause the vertebrae to fuse together, leading to decreased flexibility and severe pain.)6
  • gout and pseudogout
  • septic arthritis (This is a rare, infectious process that is more likely to affect immunocompromised patients ages 60 years and older.)
  • benign bone tumors
  • cancer5

Management of Facet Hypertrophy

Pharmacotherapy

Treatments do not cure facet hypertrophy but aim to make the patient’s pain more manageable. Common pain relievers include:

  • nonsteroidal anti-inflammatory drugs, such as ibuprofen and naproxen
  • muscle relaxants, such as cyclobenzaprine or metaxalone
  • medial branch blocks1

Nonpharmacotherapy

Patients with facet hypertrophy can benefit from regular massage and physical therapy to strengthen the core muscles and spine. Radiofrequency ablation provides temporary pain relief by using heat to destroy the medial branch of the sensory nerve.

This procedure is performed under local anesthesia. It typically gives the patient 6 to 12 months of pain relief. In some cases, patients may experience pain relief for up to 2 years. When the nerves eventually regenerate, pain returns and further treatments may be necessary. Surgery to fuse the affected vertebrae may be used, but it is not a first-line treatment and may not lead to pain relief.

Although complications following ablation are rare, follow-up should occur to make sure the patient has not experienced any negative side effects.

References

  1. Curtis L, Shah N, Padalia D. Facet Joint Disease. In: StatPearls. NCBI Bookshelf version. StatPearls Publishing; 2022. Accessed August 26, 2022.
  2. Eubanks JD, Lee MJ, Cassinelli E, Ahn NU. Prevalence of lumbar facet arthrosis and its relationship to age, sex, and race: an anatomic study of cadaveric specimens. Spine (Phila Pa 1976). 2007;32(19):2058-2062. doi:10.1097/BRS.0b013e318145a3a9.
  3. Manchikanti L, Manchikanti KN, Cash KA, Singh V, Giordano J. Age-related prevalence of facet-joint involvement in chronic neck and low back painPain Physician. 2008;11(1):67-75. PMID: 18196171.
  4. Mayo Clinic. Facet Arthritis. Accessed August 24, 2022.
  5. Julia E. C. Anaya, Silmara R. N. Coelho, Atul K. Taneja, Fabiano N. Cardoso, Abdalla Y. Skaf, and André Y. Aihara Differential Diagnosis of Facet Joint Disorders. RadioGraphics. 2021;41:2, 543-558. doi:10.1148/RG.2021200079.
  6. National Institutes of Health. National Institute of Arthritis and Musculoskeletal and Skin Diseases. Ankylosing Spondylitis. February 2020. Accessed August 26, 2022.

Author Bio

Jen Seabright, PharmD, is a freelance medical writer based in Pittsburgh, PA.