What is the diagnosis and recommended treatment for a patient with loss of writing ability (agraphia) despite normal right-hand strength, accompanied by right upper extremity pain originating from the cervical spine?

Diagnosis and Treatment of Loss of Writing Skill with Intact Right Hand Power and Cervical-Origin Right Upper Limb Pain

Primary Diagnosis: Cervical Radiculopathy with Apraxic Agraphia

This presentation most likely represents cervical radiculopathy causing right upper extremity pain combined with a central neurological disorder causing apraxic agraphia—the loss of writing ability is NOT from the cervical spine pathology but suggests a concurrent brain lesion, most commonly stroke. The preserved motor strength in the right hand with isolated loss of writing skill indicates a cortical or subcortical lesion affecting the left superior parietal lobule or left frontoparietal region, not a peripheral nerve compression 1, 2, 3.

Critical Diagnostic Distinction

The clinical presentation requires evaluation of two separate pathologies:

1. Cervical Radiculopathy Component

• Right upper limb pain originating from cervical region with intact motor power suggests nerve root irritation/compression 4
• Cervical radiculopathy affects 83 per 100,000 persons annually and presents with upper limb pain with or without sensorimotor deficits 4
• 75-90% achieve symptomatic relief with conservative therapy 4

2. Apraxic Agraphia Component

• Loss of writing ability with preserved motor strength indicates apraxic agraphia—inability to form letters despite intact motor function, spelling ability, and language 1, 2, 3
• This is a cortical disorder, not a peripheral nerve problem
• Pure agraphia can be the only presenting sign of stroke and requires urgent brain imaging 1

Immediate Diagnostic Workup

Brain Imaging (URGENT - Rule Out Stroke)

MRI brain without and with IV contrast is the priority imaging study to evaluate for:

• Acute stroke (lacunar infarction in left insula, external capsule, or internal capsule) 1
• Left frontoparietal subcortical lesions 2
• Left superior parietal lobule pathology 3

Critical pitfall: Do not attribute isolated agraphia to cervical pathology—this delays stroke diagnosis and treatment 1.

Cervical Spine Imaging (After Brain Imaging)

MRI cervical spine without IV contrast is the first-line imaging modality for chronic cervical pain with radiculopathy 4:

• Most sensitive for soft tissue abnormalities, nerve root compression, disc herniation
• Evaluates neural foramina, spinal canal, and spinal cord
• Must be interpreted with clinical findings due to frequent false-positives/negatives 4

Alternative if MRI contraindicated: CT cervical spine without IV contrast or CT myelography 4

Diagnostic Algorithm

1. Obtain detailed history:

   • Onset and progression of writing difficulty (acute suggests stroke)
   • Ability to spell words orally (preserved in apraxic agraphia)
   • Presence of other neurological symptoms (aphasia, apraxia, sensory loss)
   • Cervical pain characteristics and radiation pattern

2. Neurological examination:

   • Test letter formation ability vs. oral spelling
   • Assess for ideomotor apraxia
   • Evaluate for aphasia, alexia
   • Cervical nerve root examination (C5-T1 dermatomes/myotomes)
   • Screen for myelopathy signs 4, 5

3. Imaging sequence:

   • First: MRI brain (if acute agraphia or stroke suspected)
   • Second: MRI cervical spine (for radiculopathy evaluation)

Treatment Approach

For Apraxic Agraphia (Brain Lesion)

• If acute stroke identified: Immediate stroke protocol (thrombolysis/thrombectomy window assessment)
• Neurology consultation
• Stroke risk factor modification
• Rehabilitation/occupational therapy for writing retraining

For Cervical Radiculopathy

Conservative management is first-line (75-90% success rate) 4:

• NSAIDs for pain control
• Physical therapy focusing on cervical stabilization
• Activity modification
• Consider epidural steroid injections if conservative therapy fails
• Surgical referral only if:
  • Progressive neurological deficit develops
  • Severe refractory pain after 6-12 weeks conservative therapy
  • Myelopathy develops (requires urgent evaluation) 5

Key Clinical Pitfalls

1. Do not assume agraphia is from cervical pathology: Cervical radiculopathy causes motor/sensory deficits, not isolated cortical writing disorders 4

2. Agraphia with normal strength = brain lesion until proven otherwise: This requires urgent brain imaging to exclude stroke 1

3. MRI findings must correlate with clinical presentation: High false-positive rate in asymptomatic patients for both cervical spine and brain 4

4. Exclude myelopathy: If any upper motor neuron signs present, refer to myelopathy guidelines 4, 5

5. Consider plexopathy: If examination suggests brachial plexus involvement rather than radiculopathy, different imaging approach needed 4