Luschka's joints

In anatomy, Luschka's joints (also called uncovertebral joints, neurocentral joints)^[1] are formed between uncinate process or "uncus" below and uncovertebral articulation above.^[2] They are located in the cervical region of the vertebral column from C3 to C7.^[3] Two lips project upward from the superior surface of the vertebral body below, and one projects downward from the inferior surface of vertebral body above. These structures, which measure approximately 2 × 4 to 3 × 6 mm, are situated anteromedially to the mixed nerve root and posteromedially to the vertebral artery, vein, and sympathetic nerves as they pass through the vertebral foramen. They also contribute to the formation of the anterior wall of the intervertebral foramen.^[4] They allow for flexion and extension and limit lateral flexion in the cervical spine.

Pathological processes

Pathological processes that can occur in these joints include degenerative changes or hypertrophic arthritis, resulting in foraminal stenosis and nerve compression. Foraminal stenosis at this joint is the most common cause of cervical nerve root pressure. Radiologists frequently examine the cervical spine, and a thorough understanding of the anatomy and pathology of these joints is crucial for accurate diagnosis and therapy.^[4]

They were characterized by Hubert von Luschka in 1858.^[5][6]

Anatomical Debate

Characterized by Hubert von Luschka in 1858 as "hemiarthroses intervertebrales" or "lateral joints," he considered them homologous to dorsal costovertebral articulations. Luschka initially described them as synovial articular structures.

However, significant differences of opinion exist regarding their true nature:

• Synovial Joints: Many researchers, including Krogdahl and Torgersen, Steindler, Brain et al., Lyon, and Spurling, have described Luschka's joints as true synovial articulations, possessing a synovial membrane. They emphasize the important relationship of their location to nerve and vascular structures.
• Fibrocartilaginous Fissures: Conversely, others like Frykholm concluded that these structures belong genetically to the annulus fibrosus of the intervertebral disc and are therefore not true synovial joints but rather fibrocartilaginous fissures. Rechtman and Jackson, on the other hand, viewed them as remnants of complete synovial joints found in lower vertebrates.

Despite the ongoing debate, many contemporary anatomical textbooks either ignore Luschka's joints or refer to them only vaguely.^[4]