Ossification of the yellow ligament and spondylosis and/or ossification of the posterior longitudinal ligament of the thoracic and lumbar spine.

Combinations of varying degrees of spondylosis and/or ossification of the posterior longitudinal ligament (OPLL), and ossification of the yellow ligament (OYL) contribute to thoracic and lumbar neural compression in North Americans. Preoperative magnetic resonance and computed tomography examinations dictated the surgical approaches used to address spondylosis/OPLL in 11 patients, OYL in 12 patients, and spondylosis/OPLL and OYL in 3 patients. Myelopathy (4 patients), radiculopathy (13 patients), and cauda equina dysfunction (11 patients) were observed, 2 patients showing combined deficits. Outcomes (Odom's criteria) after laminectomy (24 patients) and circumferential thoracic procedures (2 patients) were good to excellent in the 73% of patients with spondylosis/OPLL, in 83% with OYL, and excellent for all 3 with spondylosis/OPLL and OYL. Full recognition of thoracic or lumbar spondylosis/OPLL and OYL ensure optimal surgical planning and outcomes.