This composite of four radiological images demonstrates the characteristic features of Diffuse Idiopathic Skeletal Hyperostosis (DISH) in the cervical and thoracic spine. Image A (lateral X-ray) and Image B (sagittal CT) show 'flowing' ossification along the anterolateral aspect of the vertebral column, bridging at least four contiguous vertebral bodies while maintaining relatively preserved intervertebral disc spaces. Axial CT scans (C and D) highlight the regional variation in hyperostosis distribution. In the cervical spine (C), the new bone formation (outlined in yellow) is positioned symmetrically along the anterior midline of the vertebral body, resulting in the anterior displacement of the trachea and esophagus. Conversely, the axial view of the thoracic spine (D) reveals asymmetrical ossification predominantly on the right anterolateral side, likely due to the mechanical presence of the pulsating descending aorta on the left, which inhibits bone formation. These images serve as classic examples of Forestier's disease, emphasizing the diagnostic criteria of multisegmental bridging ossification and the influence of adjacent vascular structures on disease morphology.

This diagnostic image is a lateral cervical X-ray combined with a barium swallow study. It depicts the cervical spine from C2 to C7 and the adjacent esophagus. Prominent anterior flowing osteophytes and ossification of the anterior longitudinal ligament are visible along the vertebral bodies, characteristic of Diffuse Idiopathic Skeletal Hyperostosis (DISH) or Forestier's disease. The barium contrast highlights the esophageal lumen, demonstrating a significant extrinsic compression and narrowing at the level of the C5-C6 vertebrae caused by these large anterior bony outgrowths. This finding provides a radiological explanation for mechanical dysphagia. The image serves as a clinical example of how degenerative spinal changes can impact adjacent soft tissue structures in the neck, specifically the upper digestive tract.

This lateral plain X-ray of the thoracolumbar spine demonstrates posterior spinal instrumentation and signs of Diffuse Idiopathic Skeletal Hyperostosis (DISH). The instrumentation consists of five pedicle screws connected by a vertical stabilizing rod. A critical finding is the significant 'back-out' and loosening of the most superior pedicle screw (at the L1 level), where the screw head is displaced posteriorly from the vertebral body compared to the other flush-mounted screws. The underlying anatomy shows characteristic 'flowing' anterior ossification of the vertebral bodies, consistent with DISH. There is noticeable narrowing and destructive change at the L2-L3 intervertebral disc space, suggesting pseudoarthrosis or instability. Small radiopaque markers are visible within the L2-L3 disc space, likely from a previous interbody fusion procedure. This diagnostic image illustrates a mechanical complication of spinal fusion in a patient with ankylosing spinal pathology, highlighting the risks of instrumentation failure and screw migration.

This diagnostic image displays sagittal CT reconstructions of the entire human spine, illustrating two distinct patterns of spinal ligament ossification. Image A demonstrates 'localized' pathology, primarily showing Ossification of the Posterior Longitudinal Ligament (OPLL) confined to the cervical spine region, indicated by white arrowheads. Image B represents a 'diffuse' or systemic involvement, showing multilevel ossification across the entire spinal column. In image B, white arrowheads highlight extensive OPLL and Ossification of the Anterior Longitudinal Ligament (OALL) spanning the cervical, thoracic, and lumbar segments. Additionally, white arrows in the thoracolumbar region of image B indicate concomitant Ossification of the Ligamentum Flavum (OLF) and Ossification of the Supra/Interspinous Ligaments (OSIL). The images serve to contrast localized cervical involvement with generalized spinal ligament ossification, which may be clinically associated with metabolic conditions such as non-alcoholic fatty liver disease (NAFLD) and diabetes mellitus. These radiographic features are critical for diagnosing progressive myelopathy or radiculopathy risks.

A multi-panel medical comparison chart demonstrating the detection of Ossification of the Posterior Longitudinal Ligament (OPLL) in the cervical spine using deep learning. The image is organized into three rows (A, B, C) and three columns. The left column displays lateral plain radiographs of the cervical spine. The middle column shows the same radiographs with deep learning algorithm-generated heatmaps or bounding regions highlighting suspected ossification. The right column presents sagittal CT scans, serving as the clinical ground truth. Row A illustrates continuous-type OPLL, visible as a thick, linear radiopaque structure spanning C2 to C4. Row B shows segmental-type OPLL, appearing as isolated ossified patches posterior to the C5 and C6 vertebral bodies. Row C serves as a negative control, displaying a normal cervical spine with no ligamentous ossification. This comparison illustrates how algorithmic analysis can identify subtle pathological bone formations in standard X-rays, confirmed by diagnostic CT imaging, supporting orthopaedic and radiological training in spinal pathology.

This composite diagnostic image displays a lateral cervical spine radiograph (A) alongside sagittal reconstructed CT scans (B, C) of a 60-year-old male. Image A demonstrates a focal radiopaque density within the posterior soft tissues (indicated by a yellow arrow), consistent with ossification of the nuchal ligament (ONL), while deeper structures like the posterior longitudinal ligament are obscured by overlying bone. CT image B provides a detailed sagittal view of this ONL, measuring its longitudinal extent from C4 to C5 at 2.9 cm. CT image C reveals a separate, clinically significant pathology: ossification of the posterior longitudinal ligament (OPLL), which presents as a continuous hyperdense strip along the posterior margins of the C4 to C6 vertebral bodies, measuring 3.8 cm. This comparison emphasizes the diagnostic superiority of CT over plain radiography for identifying OPLL, which may be masked on X-rays by the spinal column, and highlights the importance of further imaging when superficial ligamentous ossification is detected.