---
title: "DC 5256 - Knee, ankylosis of:"
diagnostic_code: "5256"
body_system: "Musculoskeletal System"
cfr_section: "§ 4.71a"
canonical: "https://veteranai.co/va-rating-schedule/musculoskeletal/5256-knee-ankylosis-of"
source: "https://www.ecfr.gov/current/title-38/section-4.71a"
updated: "2026-07-21T20:01:58.399154Z"
---

# DC 5256 - Knee, ankylosis of:

Rated under § 4.71a. Body system: Musculoskeletal System.

## Rating criteria

| Rating | Criteria |
| --- | --- |
| 60% | Extremely unfavorable, in flexion at an angle of 45° or more |
| 50% | In flexion between 20° and 45° |
| 40% | In flexion between 10° and 20° |
| 30% | Favorable angle in full extension, or in slight flexion between 0° and 10° |

# Knee Ankylosis — VA Disability Rating (Diagnostic Code 5256)

**Body System:** Musculoskeletal System
**Regulation:** 38 CFR § 4.71a, Diagnostic Code 5256

## What Is Knee Ankylosis?

Ankylosis of the knee refers to a knee joint that has become stiff or fixed, leaving it locked in a particular position. Because the joint no longer moves freely, the angle at which the knee is fixed plays a central role in how the condition is evaluated.

Under the VA's rating schedule, knee ankylosis is rated under Diagnostic Code 5256, which is part of the musculoskeletal criteria found in 38 CFR § 4.71a.

## Available Rating Levels

The VA assigns a disability rating for knee ankylosis based on the position and angle at which the knee is fixed. The available rating levels are:

| Rating | Criteria |
|--------|----------|
| **60%** | Extremely unfavorable, in flexion at an angle of 45° or more |
| **50%** | In flexion between 20° and 45° |
| **40%** | In flexion between 10° and 20° |
| **30%** | Favorable angle in full extension, or in slight flexion between 0° and 10° |

## What the VA Looks For

When evaluating knee ankylosis under Diagnostic Code 5256, the VA focuses on the angle at which the knee is fixed:

- **Full extension or slight flexion (0° to 10°)** is considered a more favorable position and corresponds to the 30% level.
- **Greater degrees of flexion** — where the knee is fixed in a more bent position — correspond to progressively higher ratings, moving through the 40% (10°–20°) and 50% (20°–45°) levels.
- **The most severe positions**, described as extremely unfavorable with the knee fixed in flexion at 45° or more, correspond to the 60% level.

The specific angle of the fixed joint is the key factor that determines which rating level applies.

Source: https://www.ecfr.gov/current/title-38/section-4.71a