Section 4.56 - Evaluation of muscle disabilities(a) An open comminuted fracture with muscle or tendon damage will be rated as a severe injury of the muscle group involved unless, for locations such as in the wrist or over the tibia, evidence establishes that the muscle damage is minimal.(b) A through-and-through injury with muscle damage shall be evaluated as no less than a moderate injury for each group of muscles damaged.(c) For VA rating purposes, the cardinal signs and symptoms of muscle disability are loss of power, weakness, lowered threshold of fatigue, fatigue-pain, impairment of coordination and uncertainty of movement.(d) Under diagnostic codes 5301 through 5323, disabilities resulting from muscle injuries shall be classified as slight, moderate, moderately severe or severe as follows: (1)Slight disability of muscles -(i)Type of injury. Simple wound of muscle without debridement or infection.(ii)History and complaint. Service department record of superficial wound with brief treatment and return to duty. Healing with good functional results. No cardinal signs or symptoms of muscle disability as defined in paragraph (c) of this section.(iii)Objective findings. Minimal scar. No evidence of fascial defect, atrophy, or impaired tonus. No impairment of function or metallic fragments retained in muscle tissue.(2)Moderate disability of muscles - (i)Type of injury. Through and through or deep penetrating wound of short track from a single bullet, small shell or shrapnel fragment, without explosive effect of high velocity missile, residuals of debridement, or prolonged infection.(ii)History and complaint. Service department record or other evidence of in-service treatment for the wound. Record of consistent complaint of one or more of the cardinal signs and symptoms of muscle disability as defined in paragraph (c) of this section, particularly lowered threshold of fatigue after average use, affecting the particular functions controlled by the injured muscles.(iii)Objective findings. Entrance and (if present) exit scars, small or linear, indicating short track of missile through muscle tissue. Some loss of deep fascia or muscle substance or impairment of muscle tonus and loss of power or lowered threshold of fatigue when compared to the sound side.(3)Moderately severe disability of muscles -(i)Type of injury. Through and through or deep penetrating wound by small high velocity missile or large low-velocity missile, with debridement, prolonged infection, or sloughing of soft parts, and intermuscular scarring.(ii)History and complaint. Service department record or other evidence showing hospitalization for a prolonged period for treatment of wound. Record of consistent complaint of cardinal signs and symptoms of muscle disability as defined in paragraph (c) of this section and, if present, evidence of inability to keep up with work requirements.(iii)Objective findings. Entrance and (if present) exit scars indicating track of missile through one or more muscle groups. Indications on palpation of loss of deep fascia, muscle substance, or normal firm resistance of muscles compared with sound side. Tests of strength and endurance compared with sound side demonstrate positive evidence of impairment.(4)Severe disability of muscles - (i)Type of injury. Through and through or deep penetrating wound due to high-velocity missile, or large or multiple low velocity missiles, or with shattering bone fracture or open comminuted fracture with extensive debridement, prolonged infection, or sloughing of soft parts, intermuscular binding and scarring.(ii)History and complaint. Service department record or other evidence showing hospitalization for a prolonged period for treatment of wound. Record of consistent complaint of cardinal signs and symptoms of muscle disability as defined in paragraph (c) of this section, worse than those shown for moderately severe muscle injuries, and, if present, evidence of inability to keep up with work requirements.(iii)Objective findings. Ragged, depressed and adherent scars indicating wide damage to muscle groups in missile track. Palpation shows loss of deep fascia or muscle substance, or soft flabby muscles in wound area. Muscles swell and harden abnormally in contraction. Tests of strength, endurance, or coordinated movements compared with the corresponding muscles of the uninjured side indicate severe impairment of function. If present, the following are also signs of severe muscle disability: (A) X-ray evidence of minute multiple scattered foreign bodies indicating intermuscular trauma and explosive effect of the missile.(B) Adhesion of scar to one of the long bones, scapula, pelvic bones, sacrum or vertebrae, with epithelial sealing over the bone rather than true skin covering in an area where bone is normally protected by muscle.(C) Diminished muscle excitability to pulsed electrical current in electrodiagnostic tests.(D) Visible or measurable atrophy.(E) Adaptive contraction of an opposing group of muscles.(F) Atrophy of muscle groups not in the track of the missile, particularly of the trapezius and serratus in wounds of the shoulder girdle.(G) Induration or atrophy of an entire muscle following simple piercing by a projectile.62 FR 30238, June 3, 1997 Authority: 38 U.S.C. 115