Claim Raven explanation
What this means
Muscle injuries have special combination rules based on the muscle groups, body regions, joints, and functions involved. They do not always combine in the same way as unrelated disabilities.
For example, the rule limits combining a muscle injury rating with a nerve paralysis rating of the same body part unless entirely different functions are affected. The remaining paragraphs address other combinations and limits.
How this helps your claim
This helps you understand why several injured muscle groups may not receive separately added evaluations. A clear description of the groups and functions is needed before checking the combination.
What to check in your records
Use your decision, examination reports, and relevant records to check the following points.
- Identify each injured muscle group and the affected body region.
- Review whether muscle and nerve injuries affect different functions.
- Compare the assigned ratings with the specific combination rule used.
Identify the functions covered by each proposed evaluation
Muscle groups can act on the same joint or occupy the same body region, so combining their evaluations requires attention to anatomy and function. List the injured groups and the movement or activity each affects before doing the arithmetic.
When a nerve injury is also present, identify whether its evaluation covers an entirely different function under the rule. Two diagnoses in the same limb do not automatically establish separate compensation. The medical findings should explain what each impairment does and how the effects relate.
Can I combine muscle and nerve percentages as unrelated conditions?
Not automatically. This section contains specific limits for muscle and nerve evaluations of the same body part and other muscle combinations. Read those provisions before applying the general combined-ratings table. Correct arithmetic cannot fix a combination that the governing rule does not permit.
Official regulatory text
38 CFR § 4.55
eCFR snapshot: September 3, 2026. Layout and spacing are adapted for reading. The full section and its tables are included below.
§ 4.55 Principles of combined ratings for muscle injuries.
(a) A muscle injury rating will not be combined with a peripheral nerve paralysis rating of the same body part, unless the injuries affect entirely different functions.
(b) For rating purposes, the skeletal muscles of the body are divided into 23 muscle groups in 5 anatomical regions: 6 muscle groups for the shoulder girdle and arm (diagnostic codes 5301 through 5306); 3 muscle groups for the forearm and hand (diagnostic codes 5307 through 5309); 3 muscle groups for the foot and leg (diagnostic codes 5310 through 5312); 6 muscle groups for the pelvic girdle and thigh (diagnostic codes 5313 through 5318); and 5 muscle groups for the torso and neck (diagnostic codes 5319 through 5323).
(c) There will be no rating assigned for muscle groups which act upon an ankylosed joint, with the following exceptions:
(1) In the case of an ankylosed knee, if muscle group XIII is disabled, it will be rated, but at the next lower level than that which would otherwise be assigned.
(2) In the case of an ankylosed shoulder, if muscle groups I and II are severely disabled, the evaluation of the shoulder joint under diagnostic code 5200 will be elevated to the level for unfavorable ankylosis, if not already assigned, but the muscle groups themselves will not be rated.
(d) The combined evaluation of muscle groups acting upon a single unankylosed joint must be lower than the evaluation for unfavorable ankylosis of that joint, except in the case of muscle groups I and II acting upon the shoulder.
(e) For compensable muscle group injuries which are in the same anatomical region but do not act on the same joint, the evaluation for the most severely injured muscle group will be increased by one level and used as the combined evaluation for the affected muscle groups.
(f) For muscle group injuries in different anatomical regions which do not act upon ankylosed joints, each muscle group injury shall be separately rated and the ratings combined under the provisions of § 4.25.
(Authority: 38 U.S.C. 1155)
[62 FR 30237, June 3, 1997]
Related references
- 38 CFR § 4.25: VA combined ratings: how the math works
- 38 USC § 1155: The law behind VA disability rating percentages
- 38 CFR § 4.1: What a VA disability rating measures
- 38 CFR § 3.159: VA duty to assist: records and examinations
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