Is this arm pain coming from a cervical nerve root or the thoracic outlet?
Differentiating cervical radiculopathy from neurogenic thoracic outlet syndrome in outpatient MSK, with neurological screening and red flags for myelopathy.
Subjective triage
- Arm pain often worse than neck pain, following a dermatomal pattern (for example C6 to the thumb, C7 to the middle finger).
- Symptoms aggravated by neck extension, rotation or side flexion towards the painful side.
- Some patients ease symptoms by resting the hand on top of the head.
- Thoracic outlet symptoms are more often provoked by overhead arm positions or carrying, and spread less clearly to one dermatome.
- Ask about hand clumsiness, balance change or symptoms in both arms, which may point to myelopathy.
Differential dilemma: vs neurogenic thoracic outlet syndrome
| Feature | Cervical radiculopathy vs thoracic outlet syndrome | Neurogenic thoracic outlet syndrome |
|---|---|---|
| Main provocation | Neck movements, especially extension and rotation | Sustained overhead arm positions or carrying loads |
| Distribution | Dermatomal, linked to one nerve root | Often medial arm and hand, less clearly dermatomal |
| Neck tests | Spurling's test and neck movements can reproduce arm symptoms | Neck movement usually does not change arm symptoms |
| Neurology | Possible myotomal, reflex or sensory change at one level | Neurological examination often normal |
Red flags: recognise, screen, refer
Recognise
- Hand clumsiness, loss of dexterity or gait change (possible myelopathy)
- Symptoms in both arms or legs
- Progressive or profound weakness
- Systemic features: weight loss, fever, history of cancer
- Recent significant trauma
Screen
Screen for myelopathy with history and upper motor neurone tests at every contact, and record a baseline neurological examination.
Refer
Suspected myelopathy or progressive neurological deficit needs urgent medical review. Severe trauma or suspected instability needs emergency assessment.
The clinical reasoning chain
- 1
History
Neck and right arm pain into the thumb, worse looking up and turning right.
- 2
Pattern
Dermatomal spread and neck-movement provocation fit a C6 nerve root more than the thoracic outlet.
- 3
Objective finding
Spurling's reproduces arm pain, reduced biceps reflex and thumb sensation, no upper motor neurone signs.
- 4
Diagnostic decision
Probable C6 radiculopathy without red flags: education, activity modification, graded movement and neurological monitoring.
Structures to explore in 3D
In Physivo lessons, tap an anatomical term to focus the 3D model on it. These are the key structures for this presentation.
Intervertebral foramen
The exit point for each nerve root; narrowing here is a common source of radicular symptoms.
C6 and C7 nerve roots
The levels most often involved, giving the classic thumb or middle-finger patterns.
Scalene triangle
Where the brachial plexus passes between anterior and middle scalene, relevant to thoracic outlet presentations.
Spinal cord
Compression here causes myelopathy, which is why upper motor neurone screening matters.
Quick diagnostic check
Quick reference FAQ
Which clinical tests help identify cervical radiculopathy?
A cluster of tests is more useful than any single one. Spurling's test, the distraction test, upper limb neural tension testing and reduced neck rotation together raise the likelihood, alongside a full neurological examination.
Does cervical radiculopathy need imaging?
Not routinely. Imaging is considered when red flags are present, symptoms are progressing, or the result would change management such as a surgical opinion.
What is the usual prognosis?
Many people improve over weeks to months with conservative care. Explain this honestly and safety-net for neurological change.