Muscle Group IX VA Disability Rating
Diagnostic Code 5309 · 38 CFR §4.73
What Is It?
Muscle Group IX includes the intrinsic muscles of the forearm that control fine movements of the hand. This group encompasses the muscles responsible for gripping and adjusting hand position, including the pronator and supinator muscles that rotate the forearm. These muscles allow you to turn a doorknob, use a screwdriver, and rotate your hand between palm-up and palm-down positions. Military injuries from forearm wounds, crush injuries, or fractures can damage these muscles.
Rating Criteria
| Rating | Criteria |
|---|---|
| 30% | Severe injury to the dominant arm. Non-dominant severe is rated 20 percent. |
| 20% | Moderately severe injury to the dominant or non-dominant arm. |
| 10% | Moderate injury with some loss of forearm rotation or fine hand control. |
| 0% | Slight injury with minimal functional impact. |
Evidence Needed
- Service records documenting the forearm muscle injury
- Treatment records including surgical repairs
- Forearm rotation measurements (pronation and supination)
- Functional testing of fine hand movements
- Statements describing difficulty with rotation tasks like turning knobs or using tools
C&P Exam Tips
- Have the examiner test both pronation and supination specifically
- Describe difficulty with turning movements like using a key or screwdriver
- Report any loss of fine motor control in the hand
- Show visible muscle changes on the forearm
- Mention impact on work tasks that require forearm rotation
How to File
File under DC 5309 with evidence of the forearm muscle injury and measurements of pronation and supination loss. Specify dominant arm.
Common Mistakes
Not having pronation and supination specifically measured during the exam Confusing this muscle group with the flexors or extensors which are separate groups Not describing the practical impact of losing forearm rotation Missing associated nerve injuries
Frequently Asked Questions
What is the difference between pronation and supination?
Pronation is rotating your forearm so your palm faces down. Supination is rotating so your palm faces up. Together these movements are essential for turning doorknobs, using tools, eating with utensils, and countless other daily tasks. Loss of either movement significantly impacts hand function.
Can forearm rotation loss be rated under both a muscle code and a joint code?
VA typically rates the condition under whichever code provides the higher rating. If the rotation loss is primarily from muscle damage, DC 5309 applies. If it is from joint damage, DC 5213 for impaired supination and pronation may be used instead.