Cervical spondylosis

Sudden pressure with hyperextension on the anterior cord can damage anterior horn cells and give sudden weak arms with preserved leg function.

About

• A cause of neck pain and arm weakness
• Affect the lower cervical roots
• Most disease happens at C5-6, C6-7, C3-4

Aetiology

• Simple ageing can lead to changes that impinge on the cord.
• Spondylosis is the natural wearing down of these parts of the spine.
• Disc degeneration, osteophyte formation, hypertrophy of articular facets
• A thickened ligamentum flavum all give rise to a narrowed spinal canal.
• Central protrusions give cord compression type symptoms
• Posterolateral compression on roots gives pain, paraesthesia, weakness, wasting and reduced reflexes

Risks

• Smoker
• Family history
• Neck strain e.g. painters or plumbers or flooring installers) or staring at a computer screen that is too high or low).
• Previous neck injury
• Heavy lifting like construction workers.
• Exposed to a lot of vibrations like bus or truck drivers.

Cervical Spondylotic Myelopathy occurs if cervical canal diameter falls from 17 mm to below 13 mm as the cord itself, is 8-11.5 mm in diameter.

Clinical

• Neck and arm pain with paraesthesia in arms
• Weakness, wasting and reduced reflexes in affected level in arms e.g. C5-6, C6-7, C3-4
• Reduced proprioception and touch and a progressive sensory ataxia
• Electric shock type neck pain Lhermitte's sign may occur
• Progressive difficulty walking - spastic weakness and incontinence
• Muscle spasms. Clicking, popping or grinding sound when you move your neck
• Dizziness and headaches.

Investigations

• MRI - cord can become indented, flattened and distorted. There may well be changes such as gliosis and ischaemia and demyelination. Cord atrophy and static T2 hyperintensities suggesting gliosis rather than oedema do not bode well.
• Nerve conduction studies and electromyogram may be useful

Differentials

• MND, MS, B12 deficiency
• HTLV1 myelopathy
• Adrenoleuodystrophy
• Syringomyelia and tumour

Management

• Consider Physical therapy first. Stretching and strengthening muscles. Analgesia e.g. NSAIDs and Ice and heat and massage can also provide relief. Gabapentin may help neuralgia. A soft collar worn at times may help. Wearing a hard collar for prolonged periods can cause muscle wasting. Steroids can also be injected.
• Management is surgical decompression moderate to severe cases especially with upper limb or other neurology. Spine surgery is complex and may involve a lengthy recovery. Usually, a laminectomy but other variations include discectomy. Improvement is a hit and miss affair and recovery hard to predict