Department of Anaesthesia, Royal Free Hospital, London, UK
It is the painful involvement of cervical spinal nerve roots. It presents with pain in the neck radiating to the shoulder and arms. Mostly, it is due to foraminal stenosis and degenerative spondylolysis (70 %). The second most common cause is disc herniation (mostly at C5–C6 and C6–C7 levels). The incidence is 60–70 per 100,000 population. C7 is the most common nerve root involved in isolated radiculopathy followed by C6. Risk factors include heavy weight lifting, smoking and handling vibrating equipment.
Disc protrusion causes compression of the nerves. It also releases metalloproteinases, nitric oxide and IL-6 which cause nerve root irritation and pain. Spondylosis is accompanied by osteophytes which cause compression and pain. Loss of disc height may cause alteration of anatomy and contribute to pain.
49.2 Clinical Features
Patients present with neck pain with sudden onset of radicular symptoms. Disc protrusion is associated with constant dull ache. The pain is aggravated by Valsalva manoeuvres (coughing, sneezing) and extension of the neck. The pain may be referred to the anterior chest wall, lower arm and hand. Pain is associated with numbness (70 %), weakness and areflexia/hyporeflexia with pins and needles. C1–C3 nerve root involvement presents with retro-orbital and temporal pain. C4 involvement presents with weakness of the levator scapulae and trapezius (weakness or shoulder weakness). C5 involvement leads to weakness of shoulder muscles and sensory deficit in the superolateral part of the shoulder. Biceps reflex is altered. C6 involvement causes weakness of elbow flexion and extension of the wrist. It leads to alteration of the brachioradialis reflex with sensory deficit on the lateral forearm. C7 and C8 involvement leads to weakness of the triceps and intrinsic muscles of the hand respectively. C7 is associated with decreased triceps reflex.