Ossification of the posterior longitudinal ligament (OPLL)

The human spine is formed by individual vertebrae and connective tissue discs in between. The vertebrae form the spinal canal. There are seven cervical, twelve thoracic, and five lumbar vertebrae. The intervertebral discs are the link between the individual vertebral bodies.

The little joints that link the vertebrae together are known as facet joints. They help to stabilize the spine and, together with the intervertebral discs, allow a certain degree of mobility of the spinal cord. The spinal canal should be wide enough to allow nerve roots to float freely in cerebrospinal fluid. The front border of the spinal canal is built by the vertebral bodies and intervertebral discs, the side by the intervertebral joints (facets) and back by the ligamentum flavum (yellow band) and vertebral arches. Discs consist of an outer fibrous ring (annulus fibrosus), which surrounds an inner gel-like center (nucleus pulposus). The spinal cord and nerve roots lie within the spinal canal. The spinal cord extends downwards approx. to the 1st lumbar vertebra. Below, only nerve roots are present in the spinal canal. At the level of the intervertebral disc the nerve roots pass through the neural root foramina to exit the spinal canal. The spinal cord and nerve roots conduct electric-like signals from the skin and joints to the brain, and process of movement is initiated from the brain to the muscles.

Ossification of the posterior longitudinal ligament (OPLL) is the calcification and ossification of the soft tissues connecting the vertebral bodies within the spinal canal. The thickening of the ligament gets gradually worse over time and eventually leads to chronic compression of the spinal cord.

Gradually progressing compression of the cervical spinal cord

Unsteady gait (especially in dark rooms) Stiffness, numbness and weakness of the hands and legs Retention, or unintended urinary incontinence Numbness of the genitals and loss of sexual function

Non-surgical (conservative) treatment can temporarily improve some of the symptoms in less severe cases.

Elective surgery should be considered when clinical or electrophysiological (pathological SSEP) signs of spinal cord injury are present

To release the compressed nerve roots and/or spinal cord

To stop the worsening of the symptoms

To improve symptoms (e.g. pain reduction)

To preserve the protective function of the spine

Posterior spinal canal decompression

Anterior cervical decompression and fusion