Execution
- 1Have the patient sit while the examiner explains that strength will be compared side to side.
- 2Test key cervical myotomes: shoulder elevation C4, shoulder abduction C5, elbow flexion C6, elbow extension C7, wrist extension C6, wrist flexion C7, thumb extension C8, and finger abduction / adduction T1.
- 3Apply isometric resistance for each movement and compare strength, pain, and fatigue with the opposite side.
- 4Grade weakness and check whether the pattern matches a single nerve root or suggests peripheral nerve or non-neurological weakness.
- 5Integrate strength findings with dermatomes, reflexes, and radicular provocation tests.
Positive outcome
A positive finding is reproducible weakness in a myotomal pattern, especially when it matches sensory and reflex changes. Pain-limited effort alone should not be interpreted as true myotomal weakness.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Wainner et al. (2003) | NA | NA | NA | NA | NA |
| Yousif et al. (2025) — combined neuro exam | NA | 7-14 | 98-99 | NA | NA |
CommentMyotome testing helps localise neurological deficit but has limited standalone sensitivity. It is most clinically meaningful when weakness follows a plausible root level and is supported by sensory, reflex, and neurodynamic findings. Attribution note: Yousif 2025 is a verified scoping review whose 7-14% / 98-99% figures describe the COMBINED neurological exam (myotome + dermatome + reflexes together) tested against electrodiagnosis or MRI — they are not specific to myotome testing alone. The combined-exam pattern of low sensitivity / high specificity does, however, generalise to its individual components, including myotomes.
Low Clinical Value