The joints of Luschka are also called uncovertebral joints. They are pseudojoints that have a synovial membrane with synovial fluid but no joint capsule. They exist between the third and seventh cervical vertebrae (C3 – C7). They are rudimentary at birth but develop with age (6-18 years). The joint is comprised of the uncinate processes from the vertebra above and the uncus from the vertebra below. They are formed as the intervertebral discs degenerate which allows these projections to approximate with the body of the next vertebra forming the uncovertebral joints (see the blue circle in Fig. 1). They prevent excessive lateral flexion.
Fig. 1. The blue circle indicates the joint of Luschka
- Allow for flexion and extension and limit lateral flexion in the cervical spine.
- Reinforce the intervertebral discs posterolaterally and therefore reduce the risk of disc herniation.
- Prevent posterior translation movements of the vertebral bodies.
- Provide stability and guide the motion of coupled rotation and lateral flexion.