Manual muscle test score and force comparisons after cervical spinal cord injury

Manual muscle test scores (MMTS) and maximum voluntary contraction (MVC) force measurements were made from triceps brachii muscles of 70 individuals with chronic cervical spinal cord injury (SCI). Both MMTS and strength assessments showed that asymmetrical motor deficits were common. Muscles with MMTS of 3 generated an average of nine percent MVC force produced by control muscles. In this SCI population, little residual voluntary force is apparently needed for triceps brachii to work against gravity. Only 24 percent of muscles tested had this strength, however, indicating the need to develop strategies to alleviate this muscle weakness. MMTS and force were related positively but each MMTS was not associated with a unique force range. MVC force generating capacity is therefore only one factor that determines whether or not a muscle can work with or against gravity and against resistance.