Facetjes

Facetjes, commonly referred to as facet joints (zygapophysial joints), are synovial joints between the superior and inferior articular processes of adjacent vertebrae. Each spinal motion segment has a pair of facet joints, one on the left and one on the right, formed by the inferior articular process of the upper vertebra with the superior articular process of the lower vertebra. The facet joints work together with the intervertebral discs and ligaments to guide and limit movement while contributing to spinal stability and bearing part of the axial load. They are surrounded by a fibrous capsule and lined with synovial tissue, with innervation supplied primarily by the medial branches of the dorsal rami.

The orientation of the facet joints varies by spinal region, influencing motion. In the cervical spine, facets are angled to permit a combination of flexion, extension, and rotation. Thoracic facets restrict excessive rotation and accommodate rib articulations, while lumbar facets are oriented to limit rotation and support substantial weight-bearing, allowing mainly flexion and extension with controlled lateral movements.

Common conditions affecting the facets include facet arthropathy or facet syndrome, which involves degenerative changes such as cartilage wear, facet joint hypertrophy, and inflammatory changes. Symptoms typically include localized back or neck pain that may radiate to the buttocks or thighs and pain aggravated by standing or extending the spine. Diagnosis relies on clinical assessment supported by imaging (X-ray, CT, MRI) and often confirmation through diagnostic facet joint injections or medial branch blocks, with treatment tailored to severity.

Management emphasizes conservative approaches—physical therapy, activity modification, and analgesics—with interventional options such as facet joint injections, medial branch nerve blocks, and, in refractory cases, radiofrequency ablation. Surgical fusion is considered only in selected, severe cases.