Facet Joint Osteoarthritis | Spondylosis

Facet joint osteoarthritis, also referred to as spondylosis, is a common documented source of axial lower back pain. These synovial joints, formed by the articulations of the adjacent vertebrae, allow for spinal movement while limiting excessive rotation and instability Facet Joint Disease – StatPearls – NCBI Bookshelf. They are a common site for osteoarthritis and manifest through hypertrophy, joint space loss, osteophytosis and sclerosis of the subchondral bone Lumbar Facet Arthropathy – StatPearls – NCBI Bookshelf.

Age is strongly associated with the prevalence of lumbar facet joint arthropathy, with up to 89% of adults over the age of 65 having radiographic evidence of moderate to severe changes. Other documented risk factors for developing premature facet joint osteoarthritis are a sagittal orientation of the facet joint, high BMI and concomitant intervertebral disc degeneration due to previous prolapse or surgical excision. Lumbar facet joint osteoarthritis: a review – PubMed. It is most prevalent at the L4-L5 and L5-S1 levels.

What are the signs and symptoms?

Facet-mediated joint pain typically presents with an insidious onset of central or biassed unilateral lower back pain in patients over the age of 40. Referred pain is less common but can on occasions be referred into the buttock region, but this would be in a non-specific dermatomal radiation pattern. Numbness and weakness of the lower extremities is not indicative of isolated facet joint arthropathy, but due to the degenerative changes, they may have concurrent lumbar radiculopathy via nerve root irritation Lumbar Facet Arthropathy – StatPearls – NCBI Bookshelf.

As a general rule, pain originating from the facet joints would typically manifest as back pain worse than leg pain, as apposed to pain originating from nerve root compression, which would give leg pain worse than back pain. This distinction is important, as it helps guide treatment pathways and highlight appropriate patients that would benefit from surgical intervention. Red flags (acute bowel and bladder changes, saddle anaesthesia, high velocity-trauma) should not be described and should point the practitioner away from the facet joint as the pain generator. Cauda Equina and Conus Medullaris Syndromes – StatPearls – NCBI Bookshelf.

How is it diagnosed?

Despite its prevalence Lumbar Facet Arthropathy – StatPearls – NCBI Bookshelf many patients will remain asymptomatic with a poor correlation between the severity of radiographic changes and severity of a patient’s symptoms. Facet joint disorders: from diagnosis to treatment – PubMed.

For these reasons, diagnosing facet joint disease as the sole cause of a patient’s lower back compliant is often challenging, let alone pinpointing a patient’s symptoms to a specific vertebral level Facet Joint Disease – StatPearls – NCBI Bookshelf. Physical examination may reveal localised para-lumbar tenderness; symptoms may be provoked by spinal extension and rotational movements and eased with spinal flexion; however, the sensitivity and specificity of such movements and physical findings in accurately diagnosing facet-mediated joint pain is poor. The diagnostic accuracy of the Kemp’s test: a systematic review – PMC

Imaging will still be used in the workup if symptoms persist, typically an MRI scan to exclude other potential causes of axial lower back pain and reduce the diagnostic window. Diagnostic medial branch blocks at two separate levels are the gold standard for diagnosing facet joint pain, with a significant reduction (80%) in axial symptoms following the procedure Facet Joint Injection – StatPearls – NCBI Bookshelf.

How is it treated?

For the mainstay of isolated lower back pain, there are no surgical indications. (Excluding traumatic causes due to spinal instability, malignancies or infectious causes).

Period of relative rest. For acute episodes of lower back pain +/- leg symptoms (without red flag symptoms), the vast majority will self-resolve within 12 weeks without any medical input. Facet Joint Disease – StatPearls – NCBI Bookshelf
Physiotherapy and exercise. This is an important aspect of any lower back compliant to reduce the risk of chronic symptoms, improving spinal capacity, resilience and tolerance. The best exercises are the ones the patient will be compliant with. Evidence does not support one specific rehab/exercise programme over another. Exercise intervention for patients with chronic low back pain: a systematic review and network meta-analysis – PubMed
A short cause of NSAIDs may be helpful at settling an acute flare in lower back pain. They are not intended for long-term use given the potential adverse effects on the gastrointestinal tract and renal function. Non-steroidal anti-inflammatory drugs for acute low back pain – PubMed.
For refractory cases an ultrasound-guided facet joint injection of local anaesthetic and steroid can be helpful diagnostically and provide a therapeutic benefit. Lumbar zygapophyseal joints injections under ultrasound guidance an alternative to fluoroscopy guidance in the management of low back pain – PMC. This is most commonly administered at the L4/L5 and L5/S1 levels either unilaterally or bilaterally Efficacy of Ultrasonography-Guided Injections in Patients with Facet Syndrome of the Low Lumbar Spine – PMC. This intervention should be combined in a multipronged approach including compliance with appropriate rehab and exercise.
Other treatment options include medial branch denervation, which can provide additional longer-term benefit in certain patients. Radiofrequency Denervation on Lumbar Facet Joint Pain in the Elderly: A Randomized Controlled Prospective Trial – PubMed but are not utilised in our clinics