★ Musculoskeletal
Knee Ankylosis VA Rating (DC 5256)
38 CFR § 4.71a, Diagnostic Code 5256
Overview
Ankylosis is complete immobility of the joint, whether from surgical fusion (arthrodesis) or from disease or injury that eliminates motion.
The evaluation turns on the angle at which the knee is locked — a knee fused nearly straight is functionally far better than one fused deeply bent.
Where the knee retains some motion, DC 5256 does not apply and the motion codes control; severe limitation is sometimes evaluated by analogy as functional ankylosis where the evidence supports it.
Ankylosis at the higher levels frequently raises the question of total disability based on individual unemployability.
How to Establish Service Connection
- Direct: severe in-service knee trauma, open fracture, or infection leading to fusion.
- Progression: ankylosis developing from a knee condition already service connected, including after failed reconstruction or joint infection.
- Secondary under 38 CFR § 3.310: fusion required because of a service-connected condition or its treatment.
Rating Criteria
Paraphrased from 38 CFR § 4.71a, Diagnostic Code 5256
| Rating | Criteria |
|---|---|
| 30% | Favorable angle in full extension, or in slight flexion between 0° and 10°. |
| 40% | In flexion between 10° and 20°. |
| 50% | In flexion between 20° and 45°. |
| 60% | Extremely unfavorable, in flexion at an angle of 45° or more. |
See what each percentage pays in 2026 and how it combines with your current rating →
Evidence Checklist
- Operative reports for arthrodesis or records documenting the cause of fusion.
- Imaging confirming bony or fibrous ankylosis.
- Examination findings stating the fixed angle in degrees.
- Records of assistive devices, gait effects, and effect on standing, walking, and work.
Common Secondary Conditions
Conditions frequently service-connected as secondary to Knee Ankylosis:
What the C&P Exam Documents
General information about how this condition is typically evaluated. This is not coaching on what to say and is not a substitute for medical or legal advice.
- →The single most important measurement is the angle of fixation, stated in degrees — that number selects the tier.
- →The amputation rule at 38 CFR § 4.68 caps the combined evaluation for the extremity, which can matter when ankylosis is combined with other codes.
Frequently Asked Questions
Useful Tools & Topics
Have a Knee Ankylosis claim or denial?
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Requesting a consultation does not create representation and is not a guarantee of any outcome. Representation begins only after a written fee agreement and VA Form 21-22a are signed.
Educational content only — not legal advice and not medical advice. Rating criteria on this page are summarized in plain English from 38 CFR Part 4; consult VA.gov or the current Code of Federal Regulations for official criteria. This page provides general education about how the VA rates this condition; it is not individualized advice, does not establish a representation relationship, and should not be used to self-diagnose, self-treat, or decide a course of action without speaking to a qualified clinician and a VA-accredited representative. Outcomes depend on each veteran's individual facts, evidence, and the adjudicator's judgment; no specific rating, effective date, or other result is guaranteed. Oakridge Claims is a private business and is not affiliated with, endorsed by, or operated by the US Department of Veterans Affairs.
Related Conditions
Knee Conditions
Limitation of flexion/extension, instability, and meniscus ratings.
Total Knee Replacement
100% for one year after implantation, then a minimum 30% based on residuals under DC 5055.
Knee Arthritis (Degenerative / Traumatic)
X-ray confirmed knee arthritis rated under DC 5003/5010 when motion loss is non-compensable.
Tibia and Fibula Impairment
Malunion or nonunion of the tibia/fibula rated 10%–40% under DC 5262 by knee or ankle disability.