Facet joint arthropathy

Facet joint arthropathy (also known as facet joint arthrosis) is one of the causes of lower back pain. It occurs from zygapophysial joint space reduction, osteophyte formation and hypertrophy of the articular processes that may cause spinal canal stenosis in severe cases.

Epidemiology

It is a common finding in the human lumbar spine that increases in extent and severity over aging. About half of the adults younger than 30 years have some degrees of facet arthropathy. Men have a higher prevalence compared to women.

Clinical presentation

Facet joint arthropathy is a common cause of lower back pain.

Pathology

​Repetitive mechanical low-grade trauma and stress over a long period of time has been suggested to play a role in the development of facet joint arthropathy.

Radiographic features

Radiography

Radiography is not sensitive for detection of mild osteoarthritis of the facet joints. It can detect severe cases of facet arthrosis. Oblique views are preferred over standard AP and lateral views. Joint space narrowing, subchondral sclerosis, and osteophyte formation are common radiographic findings.

CT

CT is the best imaging modality for diagnosis and grading of the facet joints. On CT, joint space narrowing, subchondral sclerosis, erosions and osteophytes formations of the facet joints are noted. Gas can also be seen inside the joint representing the vacuum phenomenon. In addition, neural foramen impingement can also be noted.

MRI

MRI is less sensitive for the diagnosis of facet arthropathy. However, it better demonstrates narrowing and compression of the theca, lateral recess, neural foramen, and nerve roots.

Single photon emission tomography (SPECT)

SPECT is highly sensitive and specific for the diagnosis of facet joints. However, the images lack adequate spatial resolution.

Treatment and prognosis

Pharmacologic therapy, steroid injection and radiofrequency ablation are the treatment options.