Lumbar Facet Joint Syndrome: Causes and Preventions in the Workplace

Background[edit | edit source]

Facet joints

The rapid development of the world demands a rise in manual labour and brings many threats to the well-being of the workers corroborated by the rise of many musculoskeletal disorders in the lower back.

Lumbar facet joint syndrome, also known as facet joint arthritis,[1] accounts for up to 40% of lower back pain[2] and has been a very prevalent issue in society spanning across all age groups.[3] Based on the data of previous studies, the risk of facet joint syndrome gets higher as age advances.

Lumbar facet joint syndrome (LFJS) is an articular disorder of the lumbar facet joint, which is also called the zygapophyseal joint (z joint). This impacts the innervation and generates pain and tenderness in the lower back region. Patients with this syndrome can experience pain in the lumbar facet joint or joint capsule, which may spread down to the limb if the syndrome is severe. Some functional movements that involve movement of the trunk may also be affected.

The anatomy of the lumbar facet joint prevents excess rotation and extension but allows a greater range of flexion. In a neutral position, the articular surface runs vertically, the superior articular processes face medially from the lower vertebral body, and the inferior articular processes face laterally from the upper vertebral body. These two processes are parallel and face each other, forming the facet joint. This joint is surrounded by a facet capsule to further stabilise the joint.

Aetiology[edit | edit source]

The degeneration of the intervertebral disc can lead to facet joint syndrome. The intervertebral disc and two-facet joints are best described as a “three-joint complex.”[4] Each joint assists and impacts the other two. The degeneration in one joint will affect the biomechanics of the entire complex. When the intervertebral disc degenerates, the annular fibres shift the load more posteriorly onto the facet joints, leading to further degeneration.

Repetitive lumbar movements, especially extension and axial rotation, would also lead to LFJS. When the lumbar spine is extending, the inferior articulate process moves inferiorly and posteriorly until the two spinous processes impact each other and restrain the extension movement. The loading force on the facet joints is greater in an extended position compared to the force in a neutral position.[2] The lumbar extensor muscles further increase facet loading during active lumbar extension, which further speeds up the degeneration process.[5] During axial rotation, the superior articular process and inferior articular process impact each other to prevent excessive rotation from occurring. This, in turn, protects the intervertebral disc from excess rotation.[2] However, because of the mechanism, the impact force on the facet joint during axial rotation can lead to degeneration, causing LFJS. The excess movement of the lumbar facet joint also causes microdamage and degeneration of the facet capsule, which can lead to further facet joint degeneration.[2] Repetitive lumbar movements causing LFJS are also backed up by numerous studies on the athletic population, specifically those who participate in sports that involve repetitive trunk rotation and extension, such as tennis. In a study on a group of elite adolescent tennis players by Alyas and colleagues, it was found that facet joint syndrome was prevalent in 70% of the sample.[6] Many golfers also experience low back pain, which is surprising since many people do not consider golf a high-risk sport. This is owed to the lumbar spine being exposed to explosive axial torsion force (one of the risk factors for LFJS), during the swing phase.[7] In addition, the misconception among people that golf is not a risky sport leads to people participating without practice and caution, which further increases the injury risk.[7]

Lordotic posture can also cause LFJS. In a lordotic posture, the lumbar curve of the spine is more defined, and the lumbar joint is in a prolonged, extended position. A more pronounced lumbar curve increases the anterior shear force and promotes vertebral slippage in an anterior direction along with disc space narrowing, which can lead to overloading of the lumbar facet joints. Eventually, it will result into facet joint arthritis.[8][9] [10]

Risk factors[edit | edit source]

  • Age[1][11]
  • Sex (male)[1][11]
  • High BMI[11]
  • An occupation that requires jolting activities and heavy lifting[11]
  • Nutritional lifestyle[1]

Clinical presentation[edit | edit source]

The clinical presentations are localised and are manifested as "pseudoradicular" lumbar pain (without any neurological deficits) that inscrease in the morning after a prolonged period of inactivity and/or stressful activities. Pain usually radiates to the buttocks, hips, groin, and thighs (unilaterally or bilaterally), typically ending above the knee.[1]

Prevention among Manual Labourers[edit | edit source]

Rapid industrialisation has posed an increased risk of musculoskeletal injuries and disorders. Lower back pain (LBP) is especially, common among manual labourers, and LFJS is one of the leading causes of LBP. As society has raised awareness of this issue, many companies are implementing interventions to lower the incidence and impact of LBP. One of the most commonly used methods is to educate workers on safe methods for performing their essential duties, as this method is accessible and less financially burdensome. For example, health and safety professionals would teach workers safe ways to do their tasks during the training session (i.e. lifting weights with a squat style instead of bending at the back, taking steps to turn instead of twisting the trunk). However, studies have found that this occupational training has no significant effect on preventing low back pain among workers.[12]

A study [13] demonstrated the effectiveness of workplace interventions on pain, disability and fear-avoidance beliefs. The workers showed a significant reduction in pain and disability but were afraid to fully return to work. The workplace intervention protocols included multidisciplinary interventions consisting of a combination of workplace assessment with work modifications; an educational program and ergonomic posture training sessions; a supervised intervention of exercise sessions of muscle strengthening, flexibility, segmental stabilisation, and endurance training in the workplace; and behavioural counselling and cognitive-behavioural therapy for LBP or stress self-management.

Workstation redesign is another popular intervention to prevent the LFJS and general LBP. The purpose of this intervention is to decrease the unnecessary movement of the trunk. Professional ergonomists would use tools from the National Institute for Occupational Safety Health (NIOSH) to determine if the workstation is safe and poses minimal risk to the worker. Workstation redesign could use modifications such as increasing the height of the workstation to minimise the need for a worker to bend to complete their work or ensuring that the most frequently used tools are directly in front of the worker to minimise the need to reach. However, each worker has different anthropometric data and companies cannot meet everyone’s needs. Very often, redesigning a workstation is impossible due to limitations associated with space and budget.

The development of new technologies, such as the Inertia Measurement Unit (IMU), a sensor technology, has been incorporated into the construction industry. An IMU sensor is wearable, real-time movement feedback equipment. It has two parts: one is placed on the middle of the upper back, and another is placed on the back of the head. These parts can process the data in real life and detect ergonomically hazardous postures and motions on the torso and neck. These hazardous postural elements then send an alarm signal to the user’s smartphone application. This real-time feedback allows the user to adjust themselves and avoid hazardous postures. [12] IMU sensors enable workers’ awareness and self-management of ergonomically hazardous postures and motions of the torso and neck and should be implemented in other industries in the future.[14]

Physiotherapy Management of LFJS[edit | edit source]

The management of LFJS is a multifold process. The rehabilitation should have a holistic approach. It should focus on:

  1. Patient Education
  2. Ergonomic Advice
  3. Pain Management with medications, and modalities.
  4. Improving mobility: with spinal manipulations and exercises.
  5. Strengthening
  6. Back to Work training

Read more on this page about Lumbar Facet Syndrome.

Conclusion[edit | edit source]

In conclusion, the causes of LFJS can be categorised into three points: 1) degeneration of the intervertebral disc that causes the degeneration of lumbar facet joints; 2) repetitive lumbar joint movement; 3) lordotic postures. In various workplaces, many workers struggle with LFJS, yet there has not been any effective method to manage it. Educating workers is still the most used prevention but has been proven to be ineffective. Workstation redesign is a good prevention technique but companies are not able to accommodate due to limited space and budget. The new real-time motion feedback technology is promising to prevent workers from performing risky postures, but it still needs time for further development and on-site tests.

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 Kalichman L, Hunter DJ. Lumbar facet joint osteoarthritis: a review. InSeminars in arthritis and rheumatism 2007 Oct 1 (Vol. 37, No. 2, pp. 69-80). WB Saunders.
  2. 2.0 2.1 2.2 2.3 Beresford ZM, Kendall RW, Willick SE. Lumbar facet syndromes. Current Sports Medicine Reports. 2010; 9(1):50-6
  3. 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. 2007;32(19):2058-62.
  4. Varlotta GP, Lefkowitz TR, Schweitzer M, Errico TJ, Spivak J, Bendo JA, Rybak L. The lumbar facet joint: a review of current knowledge: part 1: anatomy, biomechanics, and grading. Skeletal radiology. 2011;40(1):13-23.
  5. Cavanaugh JM, Ozaktay AC, Yamashita HT, King AI. Lumbar facet pain: biomechanics, neuroanatomy and neurophysiology. Journal of biomechanics. 1996 Sep 1;29(9):1117-29.
  6. Alyas F, Turner M, Connell D. MRI findings in the lumbar spines of asymptomatic, adolescent, elite tennis players. British journal of sports medicine. 2007;41(11):836-41.
  7. 7.0 7.1 Gluck GS, Bendo JA, Spivak JM. The lumbar spine and low back pain in golf: a literature review of swing biomechanics and injury prevention. The Spine Journal. 2008;8(5):778-88.
  8. Berlemann U, Jeszenszky DJ, Bühler DW, Harms J. The role of lumbar lordosis, vertebral end-plate inclination, disc height, and facet orientation in degenerative spondylolisthesis. Journal of spinal disorders. 1999; 12(1):68-73.
  9. Dunlop RB, Adams MA, Hutton WC. Disc space narrowing and the lumbar facet joints. The Journal of bone and joint surgery. British volume. 1984;66(5):706-10.
  10. Jentzsch T, Geiger J, König MA, Werner CM. Hyperlordosis is associated with facet joint pathology at the lower lumbar spine. Clinical spine surgery. 2017; 30(3):129-35.
  11. 11.0 11.1 11.2 11.3 Gellhorn AC, Katz JN, Suri P. Osteoarthritis of the spine: the facet joints. Nature Reviews Rheumatology. 2013 Apr;9(4):216-24.
  12. 12.0 12.1 Van Poppel MN, Hooftman WE, Koes BW. An update of a systematic review of controlled clinical trials on the primary prevention of back pain at the workplace. Occupational Medicine. 2004;54(5):345-52.
  13. Russo F, Papalia GF, Vadalà G, Fontana L, Iavicoli S, Papalia R, et al. The Effects of Workplace Interventions on Low Back Pain in Workers: A Systematic Review and Meta-Analysis. International Journal of Environmental Research and Public Health [Internet]. 2021 Nov 30;18(23):12614. Available from: http://dx.doi.org/10.3390/ijerph182312614
  14. Yan X, Li H, Li AR, Zhang H. Wearable IMU-based real-time motion warning system for construction workers' musculoskeletal disorders prevention. Automation in Construction. 2017;74:2-11.