Other synovitis and tenosynovitis, unspecified thigh

This code represents inflammation of the synovial membrane (synovitis) or the tendon sheath (tenosynovitis) affecting an unspecified area of the thigh. It indicates a non-specific inflammatory process within these structures, without further detail regarding the specific type of synovitis or tenosynovitis.

Use this code when documentation specifies synovitis or tenosynovitis of the thigh, but the laterality (right or left) is not documented, and the specific type of inflammation is not identified. This code is appropriate when the provider has diagnosed inflammation of these structures in the thigh but has not provided more specific diagnostic information.

• Avoid using this code if laterality (right or left thigh) is documented; instead, use the more specific codes M65.851 (right) or M65.852 (left).
• Ensure the documentation clearly states "thigh" as the anatomical site. If the site is unspecified beyond the thigh, a more general unspecified code may be necessary.
• This code is for conditions not classified elsewhere; if a more specific type of synovitis or tenosynovitis (e.g., infectious, crystal-induced) is documented, use the appropriate specific code.