Cervical Radiculopathy, Not Diabetic Neuropathy
This patient has cervical radiculopathy, not diabetic peripheral neuropathy, and requires cervical spine imaging (MRI) followed by conservative management including physical therapy, NSAIDs, and potentially cervical traction. 1, 2
Why This Is Cervical Radiculopathy
The clinical presentation is incompatible with diabetic neuropathy and classic for cervical radiculopathy:
Pain distribution is wrong for diabetic neuropathy – symptoms began in the wrist and radiate proximally to biceps, trapezius, and shoulder, whereas diabetic peripheral neuropathy presents with distal symmetric symptoms starting in the feet and toes, not isolated upper extremity pain 3
Negative Phalen's test excludes carpal tunnel syndrome – this rules out the most common focal nerve entrapment that could explain wrist-to-arm symptoms 1
Mechanical pain pattern is diagnostic – lateral arm elevation increases discomfort and sudden jerking movements escalate pain to 10/10, which are classic mechanical provocations seen in cervical radiculopathy, not neuropathy 1, 2
Onset after awkward sleeping position – this temporal relationship strongly suggests mechanical nerve root compression rather than metabolic neuropathy 2
Two-month progressive course – cervical radiculopathy typically presents with neck and arm pain that can persist for weeks to months, whereas acute diabetic neuropathy would present bilaterally and symmetrically 4, 2
Critical Diagnostic Steps
Perform cervical spine examination immediately:
Check for neck pain and limited cervical range of motion, which are the most common findings in cervical radiculopathy 1, 2
Perform Spurling test (cervical extension with lateral flexion and axial compression toward the symptomatic side) – reproduction of radicular pain confirms nerve root compression 1, 2
Perform shoulder abduction test (patient actively abducts shoulder and places hand on head) – relief of symptoms suggests cervical radiculopathy 1
Assess deep tendon reflexes, particularly triceps reflex (C7), as diminished reflexes are the most common neurologic finding in cervical radiculopathy 1, 2
Test dermatomal sensation in C5-C8 distributions and assess motor strength in corresponding myotomes 2
Examine lower extremities to definitively exclude diabetic neuropathy:
Perform 10-g monofilament testing on plantar surfaces of both feet 4, 3
Test vibration perception with 128-Hz tuning fork at great toes and malleoli 4, 3
Assess ankle reflexes bilaterally 3
If lower extremity examination is completely normal with no distal sensory loss, diabetic peripheral neuropathy is effectively ruled out as the cause of arm symptoms 3
Imaging and Electrodiagnostic Testing
Order cervical spine MRI without delay:
MRI is indicated because symptoms have persisted for two months, which exceeds the initial conservative management window of 4-6 weeks 1
MRI will identify disc herniation, foraminal stenosis, or other structural pathology compressing cervical nerve roots 2, 5
The most common levels affected are C5-C6 and C6-C7, which produce radicular symptoms in the distribution described 2, 6
Electrodiagnostic studies (EMG/NCS) are indicated if:
You need to differentiate cervical radiculopathy from peripheral neuropathy or brachial plexopathy 3, 2
There is concern for multilevel involvement or coexisting peripheral nerve pathology 2
Initial Conservative Management
Most cervical radiculopathy cases resolve with conservative treatment regardless of specific intervention: 1
Physical therapy is first-line, including cervical strengthening exercises, stretching, and potentially intermittent cervical traction 1, 6, 5
NSAIDs for anti-inflammatory effect and pain control 1
Muscle relaxants for associated cervical muscle spasm 1
Avoid high-velocity cervical manipulation given the risk of worsening disc herniation or precipitating symptomatic herniation from asymptomatic disease 5
Continue conservative management for 4-6 weeks before considering epidural steroid injections or surgical referral 1
Red Flags Requiring Urgent Intervention
Refer immediately to neurosurgery if any of the following develop:
Progressive motor weakness or loss of grip strength (patient currently denies grip loss, but monitor closely) 1, 2
Upper motor neuron signs suggesting cervical myelopathy (hyperreflexia, Babinski sign, gait disturbance) 3, 2
Bowel or bladder dysfunction 2
Severe or rapidly progressive neurologic deficits 2
Address Diabetes Control Separately
While cervical radiculopathy is the primary diagnosis, uncontrolled diabetes requires concurrent management:
Check HbA1c, fasting glucose, and comprehensive metabolic panel to assess diabetes control and screen for diabetic complications 4, 3
Screen for diabetic peripheral neuropathy in lower extremities with monofilament and tuning fork testing, as up to 50% of diabetic neuropathy is asymptomatic 4, 3
Target HbA1c of 6-7% to prevent future neuropathy development, though this will not affect the current cervical radiculopathy 4, 7
Initiate or optimize glucose-lowering therapy as indicated by HbA1c results 4
Common Pitfalls to Avoid
Do not assume bilateral arm pain in a diabetic patient is automatically diabetic neuropathy – diabetic peripheral neuropathy does not present with isolated upper extremity symptoms without typical distal lower extremity involvement first 3
Do not delay cervical spine imaging when mechanical symptoms and provocative maneuvers suggest radiculopathy, especially after two months of symptoms 1
Do not prescribe pregabalin or duloxetine for this pain – these are indicated for neuropathic pain from diabetic peripheral neuropathy, not mechanical radicular pain from nerve root compression 4, 7
Do not overlook vitamin B12 deficiency if the patient were on metformin (currently denies medications, but verify) – B12 deficiency can cause or worsen neuropathy and should be screened 4, 8