Ossified Posterior Longitudinal Ligament (OPLL)
What it is
A ligament called the posterior longitudinal ligament runs down the back of the vertebral bodies, just in front of the spinal cord. In OPLL, this ligament gradually turns to bone. As it thickens, it takes up space in the canal and can press on the spinal cord. It is most common in the neck and occurs more often in people of East Asian descent.
What it feels like
OPLL often causes no symptoms for years. When the ossified ligament begins to crowd the cord, it produces the signs of myelopathy: clumsy hands, numbness, balance or gait trouble, and weakness. Some people also have neck pain or pinched-nerve symptoms in an arm.
How we diagnose it
A CT scan shows the ossified ligament especially well, since it is now bone, while an MRI shows how much the cord is being compressed. Together they tell me how far the process has gone and whether the cord is at risk.
How we treat it
OPLL without cord symptoms is often watched, with attention to protecting the neck from injury. Once there are clear or progressing signs of cord compression, surgery to make room for the cord is usually recommended — frequently from the back (a laminoplasty, which reopens the canal while preserving some motion), and in selected cases from the front. As with other cord conditions, the aim is to act before the cord is badly affected.
The science — for the curious
OPLL is treated with the same respect as other causes of cord compression: because the cord recovers poorly once it is significantly affected, the decision to operate is driven by cord signs and their trajectory, not by the size of the ossification alone. A particular caution is that a canal already narrowed by OPLL leaves less room to absorb a fall or blow, so even before surgery is needed, protecting the neck matters.
Learn more
OrthoInfo — Cervical Spondylotic Myelopathy: orthoinfo.aaos.org
North American Spine Society — Cervical Stenosis & Myelopathy: spine.org / KnowYourBack
This handout is general education about a common condition and does not replace the personalized advice we discuss in clinic. If anything here does not match what we talked about, what we talked about wins — please ask me.