Rupture of synovium, unspecified toe(s)

This code signifies a tear or break in the synovial membrane surrounding a joint in an unspecified toe. This rupture can lead to pain, swelling, and impaired joint function. It typically results from trauma or degenerative processes.

Apply this code when documentation clearly indicates a rupture of the synovium in a toe, but the specific toe (e.g., great toe, lesser toe) is not identified. Supporting documentation should include physician notes detailing the diagnosis of a synovial rupture and the lack of laterality or specific toe identification.

• Ensure documentation specifies "rupture of synovium" and not just a sprain or strain.
• Avoid using this code if the specific toe (e.g., M66.171 for right great toe) is documented; use the more specific code.
• If the cause of the rupture is known (e.g., traumatic), consider an external cause code (V00-Y99) as a secondary diagnosis.