What symptoms are associated with a C4-C5 impingement on the spinal cord?

Symptoms of C4-C5 Spinal Cord Impingement

A C4-C5 impingement on the spinal cord typically produces a combination of upper and lower extremity symptoms, including weakness in the deltoids and biceps, sensory changes in the shoulders and lateral arms, and potential respiratory compromise due to diaphragmatic involvement.

Neurological Manifestations

Motor Symptoms

• Weakness in the deltoids and biceps muscles (C5 innervation)
• Potential diaphragmatic weakness (C3-C5 phrenic nerve innervation) 1
• Difficulty with shoulder abduction and elbow flexion
• Progressive muscle atrophy in affected muscle groups
• Potential bilateral upper limb C5 paralysis 2

Sensory Symptoms

• Numbness and paresthesia in the lateral aspect of the upper arms and shoulders
• Pain radiating from the neck into the shoulders and arms
• Sensory changes in the C5 dermatome (lateral arm)
• Potential "suspended" sensory loss with preserved sensation above and below the affected area 3

Reflex Changes

• Diminished or absent biceps and brachioradialis reflexes
• Potential hyperreflexia below the level of compression
• Abnormal triceps tendon reflex (91.7% of cases with C4-C5 compression) 4

Progression of Symptoms

Early Manifestations

• Neck pain that may radiate to the shoulders
• Subtle weakness in the shoulders and arms
• Numbness or tingling in the upper extremities
• Decreased range of motion in the neck

Advanced Manifestations

• Progressive weakness and atrophy in upper extremities
• Development of spasticity in lower extremities
• Wide-based, unsteady gait
• Bowel and bladder dysfunction in severe cases 5
• Potential respiratory compromise in severe cases

Atypical Presentations

• Some patients may present with isolated lower extremity symptoms without upper extremity involvement 5
• Bilateral isolated C5 paralysis without sensory loss has been reported 2
• Symptoms may mimic lumbar pathology, leading to diagnostic delays

Relative Vulnerability of Spinal Cord Tracts

Research indicates that with C4-C5 compression, spinal cord tracts are affected in the following order of vulnerability 4:

1. Burdach tract (posterior column - fine touch, vibration)
2. Lateral corticospinal tract (motor function)
3. Posterior horns (layers 4,5 - pain and temperature)
4. Goll tract (posterior column - position sense)

Clinical Pearls and Pitfalls

Important Considerations

• C4-C5 impingement may present with symptoms that mimic lumbar pathology, leading to misdiagnosis
• Always consider cervical pathology when evaluating patients with bilateral lower extremity symptoms and neurogenic bladder dysfunction 5
• Respiratory function should be monitored in patients with high cervical compression (C3-C5) due to potential diaphragmatic involvement

Diagnostic Pitfalls

• Focusing only on the lumbar spine when a patient presents with lower extremity symptoms
• Failing to perform a complete neurological examination that includes upper and lower extremities
• Missing subtle signs of myelopathy such as Hoffman's sign or inverted radial reflex

Management Considerations

For patients with confirmed C4-C5 spinal cord impingement:

• Conservative management with physical therapy and medication may be appropriate for mild cases 1
• Surgical decompression should be considered for progressive neurological deficits, severe pain, or evidence of spinal instability 1
• Early intervention is critical to prevent permanent neurological damage, particularly when myelomalacia is present 6

Understanding these symptom patterns is essential for prompt diagnosis and appropriate management of patients with C4-C5 spinal cord impingement, as delayed treatment can lead to irreversible neurological damage.