Boutonniere deformity of unspecified finger(s)

This code signifies a Boutonniere deformity affecting one or more unspecified fingers. This condition involves a disruption of the central slip of the extensor tendon, causing the proximal interphalangeal (PIP) joint to flex and the distal interphalangeal (DIP) joint to hyperextend.

Use this code when documentation clearly states a Boutonniere deformity is present, but the specific finger(s) affected are not identified. This typically occurs in initial assessments or when the laterality is also unspecified.

• Avoid using this code if the specific finger (e.g., thumb, index finger) is documented; instead, use a more specific code from the M20.02 category.
• Ensure the documentation explicitly mentions "Boutonniere deformity" or describes the characteristic PIP flexion and DIP hyperextension.
• Query the provider for laterality and specific finger involvement if not documented, to allow for more precise coding.