Osteoarthritis of knee (M17)

The ICD-10 code M17 and its subcodes specifically classify different forms of osteoarthritis affecting the knee, including distinctions by side, cause, and extent. These codes help identify whether the condition is primary or secondary, unilateral or bilateral, and whether trauma is involved.

Osteoarthritis of the knee, commonly referred to in various ways such as "primary gonarthrosis," "patellofemoral osteoarthritis," or simply "osteoarthritis of the knee," is precisely categorized within this section. For example, M17.0 covers bilateral primary osteoarthritis, including terms like "bilateral disorder of patellofemoral joints," while M17.1 differentiates unilateral primary cases with further detail down to right (M17.11) or left knee (M17.12). Traumatic origins are coded under M17.2 and M17.3, specifying bilateral or unilateral post-traumatic osteoarthritis, sometimes noted as "gonarthrosis due to trauma." Secondary osteoarthritis, indicating arthritis caused by another condition, falls under M17.4 and M17.5 for bilateral and unilateral cases, respectively. When laterality or specifics are unknown, M17.9 is used for unspecified osteoarthritis of the knee. These distinctions are essential for accurate diagnosis coding and treatment planning in knee osteoarthritis.