Screening and Predictive Value of Thoracic Ossification Observed on Lateral Radiography for Myelopathy.

Area of Science:

• Neurosurgery
• Radiology
• Orthopedics

Background:

• Ossification of the ligamentum flavum (OLF) can compress the spinal cord, leading to myelopathy.
• Thoracic OLF is often underdiagnosed due to imaging challenges, and radiographs lack screening criteria.

Purpose of the Study:

• To establish radiographic criteria for screening clinically significant thoracic OLF.
• To determine if lateral radiographs can identify thoracic OLF associated with myelopathy.

Main Methods:

• Retrospective study of 142 patients with thoracic OLF (69 with myelopathy, 73 without).
• Analysis of radiographic and clinical data, including OLF diameter and OLF diameter ratio on lateral radiographs.

Main Results:

• The OLF diameter ratio was significantly larger in the myelopathy group (0.63±0.15) vs. non-myelopathy group (0.42±0.33).
• An OLF diameter ratio ≥0.58 on lateral radiographs showed 73% sensitivity and 82% specificity for predicting myelopathy.

Conclusions:

• The OLF diameter ratio on lateral radiographs is a non-invasive parameter for identifying thoracic OLF with myelopathy.
• A ratio ≥0.58 warrants further investigation with CT or MRI to guide treatment.