Fusion of spine, thoracolumbar region

This code indicates a pathological fusion of vertebrae in the thoracolumbar region of the spine, meaning an abnormal joining of two or more vertebral bodies. This can result from various underlying conditions, leading to restricted spinal movement and potential neurological compromise. It describes the condition of fusion, not the surgical procedure to achieve fusion.

Use this code when documentation clearly states a diagnosis of spontaneous or pathological fusion of the thoracic and/or lumbar spine. This typically applies to conditions like ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis (DISH), or advanced degenerative changes leading to natural bony bridging. Supporting documentation includes imaging reports (X-ray, CT, MRI) confirming the fusion.

• Do not confuse this code with surgical arthrodesis (fusion); this code represents a pathological state.
• Specify the exact spinal region if possible (e.g., M43.24 for thoracic, M43.26 for lumbar) if the documentation is more precise than "thoracolumbar."
• Always code the underlying condition causing the fusion (e.g., ankylosing spondylitis, DISH) first, as this code describes a manifestation.