Open wound of knee, leg [except thigh], and ankle, with tendon involvement

This code signifies an open injury to the knee, lower leg (excluding the thigh), or ankle where there is a visible break in the skin and damage to one or more tendons. This type of wound often involves a laceration or puncture that extends deep enough to affect the underlying tendinous structures.

Apply this code when documentation clearly indicates an open wound in the specified anatomical areas with explicit mention of tendon involvement, such as a severed or partially torn tendon. This is typically seen in traumatic injuries like deep cuts from sharp objects or crush injuries.

• Ensure documentation specifies "open wound" and explicitly identifies tendon involvement; superficial open wounds without tendon damage are coded differently.
• Distinguish from closed tendon injuries (e.g., ruptures without skin breach) and open wounds without tendon involvement.
• Always sequence this code as a primary diagnosis when it represents the main reason for the encounter, followed by any associated complications or external cause codes.