M24.661 is the authoritative medical code for Ankylosis, right knee. This classification is used in medical billing and clinical recording to specify the clinical criteria for ankylosis, right knee (ICD-10-CM M24.661), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Ankylosis, right knee is a billable ICD-10-CM diagnosis code M24.661. Excludes1 (not coded here): stiffness of joint without ankylosis M25.6-; current injury - see injury of joint by body region. Excludes2 (not included here): spine M43.2-; ganglion M67.4; snapping knee M23.8-; temporomandibular joint disorders M26.6-; joints of the spine M40-M54.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for M24.661 in the official ICD-10-CM tabular list.
Excludes1 — Not Coded Here
Conditions that can never be reported with this code; the two are mutually exclusive.
- stiffness of joint without ankylosis M25.6-
- current injury - see injury of joint by body region
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- spine M43.2-
- ganglion M67.4
- snapping knee M23.8-
- temporomandibular joint disorders M26.6-
- joints of the spine M40-M54
Frequently Asked Questions (FAQ) & Clinical Guidance
What can't be coded together with M24.661?
Per official ICD-10-CM Excludes1 instructions, M24.661 must not be reported together with: stiffness of joint without ankylosis (M25.6-); current injury - see injury of joint by body region.
Can M24.661 be reported alongside related conditions?
Per official ICD-10-CM Excludes2 instructions, M24.661 and the following are not considered part of each other and may both be reported when both conditions are present: spine (M43.2-); ganglion (M67.4); snapping knee (M23.8-); temporomandibular joint disorders (M26.6-).
Nearest Codes in This Family
Official ICD-10-CM classifications closest to M24.661 in its code family, with their registry titles.
- M24 — Other specific joint derangements
- M24.0 — Loose body in joint
- M24.00 — Loose body in unspecified joint
- M24.01 — Loose body in shoulder
- M24.011 — Loose body in right shoulder
- M24.012 — Loose body in left shoulder
- M24.019 — Loose body in unspecified shoulder
- M24.02 — Loose body in elbow
- M24.021 — Loose body in right elbow
- M24.022 — Loose body in left elbow
View all 40 codes in the M24 family