Ossification of the Nuchal Ligament With Text Neck Syndrome.

Ossification of the nuchal ligament (ONL) is a common but frequently overlooked radiographic finding on lateral cervical spine imaging, characterized by ectopic bone formation within the nuchal ligament, most often at the C4/5 and C5/6 levels. Although usually asymptomatic, ONL has been associated with cervical spondylosis, segmental instability, and, importantly, a markedly increased risk of coexisting ossification of the posterior longitudinal ligament (OPLL), a condition with potential for progressive myelopathy. We conducted a narrative review of the PubMed-indexed literature on the anatomy, epidemiology, classification, and clinical significance of ONL, illustrated with the case of a 61-year-old female who presented with neck stiffness and headache in the context of habitual mobile phone use of 10 hours per day. Lateral cervical radiography demonstrated loss of normal cervical lordosis, moderate degenerative disc disease most severe at C5/6, and ossification of the ligamentum nuchae posterior to C4 and C5, consistent with moderate cervical spondylosis. She improved with four weeks of care. This case illustrates the classic radiographic and clinical profile of ONL in the setting of reported prolonged device use and forward head posture, highlighting a possible contributing mechanical factor. Given the strong statistical link between ONL and OPLL, primary healthcare providers who incidentally identify ONL on lateral cervical radiographs should consider it a clinical marker warranting careful neurological evaluation. Advanced cross-sectional imaging (CT or MRI) is not automatically indicated for isolated, asymptomatic ONL, but should be considered when neurological signs or symptoms, suspected myelopathy, progressive deficits, trauma, or specific manual therapy safety considerations arise.