I Thought It Was a Herniated Disc, but the Ligament Turned into Bone?

There is a disease with symptoms similar to a herniated cervical disc, but in which the ligament hardens and turns into bone.

This disease is called ossification of the posterior longitudinal ligament (OPLL). When affected, symptoms such as hand numbness, sensory abnormalities, and muscle weakness occur, and in severe cases, walking and bowel movement disorders may appear.

The spine consists of 33 bones, ranging from the cervical vertebrae in the neck to the sacrum near the tailbone. Additionally, the spine contains several ligaments that act as supports to ensure proper alignment, movement, and stabilization of the bones. Representative ligaments include the anterior longitudinal ligament at the front of the spine and the posterior longitudinal ligament at the back.

When the posterior longitudinal ligament hardens and ossifies due to various causes, it compresses the nerves passing through the spinal canal, causing neurological symptoms. This condition is known as ossification of the posterior longitudinal ligament (OPLL). The spinal canal is a hollow, tube-shaped space in the center of the spine through which nerves pass from the brain to the limbs.

The exact cause of OPLL has not yet been identified. It occurs more frequently in East Asians and is known to be closely related to family history. It is also associated with external trauma, obesity, ankylosing spondylitis, diabetes, and immune diseases.

OPLL commonly occurs in the cervical spine, which consists of seven vertebrae at the top of the spine. Many cases are asymptomatic, but in the early stages, symptoms such as pain, pressure, and discomfort in the cervical area gradually progress. Symptoms can worsen rapidly due to minor trauma or when joints extend beyond their normal range of motion.

As the posterior longitudinal ligament becomes harder and larger, it strongly compresses the nerves in the spinal canal, leading to hand numbness, sensory abnormalities, and muscle weakness, which eventually extend to the legs.

Bone degeneration, where bone tissue breaks down or dissolves and calcium is lost, also accompanies this condition. In severe cases, walking and bowel movement disorders may occur.

Diagnosis can be easily confirmed with X-ray examinations, but additional radiological tests such as CT and MRI are performed to check the size and shape of the ossified area, nerve degeneration, and the degree of spinal cord compression.

Neck pain image. [Image source=Clipart Korea]

In the early stages of onset, it is advisable to limit excessive exercise and rest. Non-surgical treatments such as medication with anti-inflammatory analgesics and steroids, physical therapy, and wearing braces are also implemented to relieve symptoms.

If symptoms do not improve with non-surgical treatment and severe spinal canal involvement causes intense pain and neurological disorders such as walking and movement difficulties, surgery should be considered.

In the cervical spine, the ossified area is removed through vertebral body resection. However, if the ossification is extensive or there is a risk of spinal cord injury during surgery, procedures such as laminectomy or laminoplasty are performed depending on the patient's condition.

Jung Dong-moon, director of the Spine Center at Daedong Hospital, said, “Neurological symptoms such as numbness in the hands or legs can appear in various diseases, but many patients visiting outpatient clinics tend to underestimate the condition, thinking that modern people all have discs, and thus miss the appropriate timing for treatment.” He advised, “If symptoms appear, rather than self-diagnosing, patients should get diagnosed by a neurosurgery specialist and receive proper treatment early.”

He added, “To prevent ossification of the posterior longitudinal ligament, it is best to avoid excessive neck rotation or bending sideways, and to refrain from postures that cause severe neck flexion, such as using media devices while lying down or studying while lying face down.”

This content was produced with the assistance of AI translation services.