What symptoms would I experience if a previously non‑displaced, stable fracture of the sixth cervical vertebra (C6) became displaced?

What You Would Experience if a Stable C6 Fracture Became Displaced

If you displaced a previously stable, non-displaced C6 fracture, you would most likely experience sudden onset of severe neck pain, new or worsening arm weakness, numbness or tingling in your hands and arms, and potentially difficulty with hand coordination—with the most concerning scenario being rapid progression to paralysis if spinal cord compression occurs. 1, 2

Immediate Neurological Symptoms to Expect

The displacement of a C6 fracture can cause acute spinal cord or nerve root compression, leading to:

• Motor deficits: Weakness or complete loss of function in your arms and hands, particularly affecting grip strength and fine motor control. In severe cases, this can progress to involve your legs, causing difficulty walking or complete paralysis. 1, 2, 3

• Sensory changes: Numbness, tingling, or burning sensations radiating down your arms into your hands and fingers (radiculopathy). You may experience loss of sensation on one or both sides of your body. 2, 3

• C5 ASIA B or worse deficits: In documented cases of C5-6 displacement, patients developed specific patterns of weakness and sensory loss consistent with spinal cord injury classifications, with some progressing from no deficits to severe impairment within hours. 2

• Hemiplegia: In extreme cases with complete laminar fracture displacement and cord compression, complete one-sided paralysis has been reported. 3

Pain Characteristics

• Severe, acute neck pain that is distinctly worse than your baseline discomfort from the stable fracture. 4, 2

• Radicular pain: Sharp, shooting pain down one or both arms following the C6 nerve root distribution (typically affecting the thumb and index finger). 2, 5

• Midline cervical tenderness that is focal and significantly more pronounced than before. 2

Autonomic and Functional Symptoms

• Bladder dysfunction: Inability to urinate or loss of bladder control, which indicates significant spinal cord involvement. 2

• Respiratory compromise: Depending on the extent of cord injury, you may experience difficulty breathing if higher cervical segments become involved. 6

• Loss of coordination: Difficulty with balance and fine motor tasks, particularly in your hands. 3

Timeline of Symptom Progression

The critical danger is that neurological deterioration can occur rapidly—within hours of the displacement. 1, 2

• In one documented case, a patient with an initially "negative" CT scan developed progressive hand and lower limb weakness with urinary retention over just a few hours after discharge, ultimately revealing C5-6 subluxation with cord compression on MRI. 2

• 67% of patients with missed cervical fractures suffer neurological deterioration, and delayed diagnosis produces 10 times higher rates of secondary neurological injury (10.5% vs 1.4%). 1

• Before modern trauma protocols, up to 10% of initially neurologically intact patients developed deficits during emergency care due to unrecognized instability. 6

Critical Warning Signs Requiring Emergency Evaluation

Seek immediate emergency care if you experience ANY of the following:

• New or worsening arm or hand weakness 1, 2
• Numbness or tingling in your arms, hands, or legs 2, 3
• Difficulty walking or leg weakness 2
• Inability to urinate or loss of bowel/bladder control 2
• Sudden increase in neck pain severity 4, 2
• Any sensation changes below the level of your neck 1, 3

Why Displacement Causes These Symptoms

When a stable C6 fracture becomes displaced, the following mechanisms cause neurological injury:

• Direct spinal cord compression: Bone fragments or rotated vertebral elements compress the spinal cord, causing immediate dysfunction. 3

• Nerve root impingement: Displaced bone fragments can trap exiting nerve roots at the neural foramen, causing radiculopathy. 5

• Ligamentous disruption: Displacement often indicates failure of the posterior longitudinal ligament, ligamentum flavum, and disc structures, allowing abnormal vertebral movement that further compresses neural structures. 2

• Vascular compromise: In rare cases, displacement can affect vertebral artery flow, though this is more concerning for surgical planning than acute symptoms. 5

Common Pitfall to Avoid

Do not assume that absence of immediate symptoms means the fracture hasn't displaced. CT scans can miss isolated ligamentous injuries and subtle subluxations that are only visible on MRI, and neurological symptoms can develop hours after the actual displacement event. 2 The case literature demonstrates that patients with "negative" CT scans can harbor unstable injuries that progress to devastating neurological deficits. 2