Nucleus pulposus C4-C5

Looks like

The soft, gel-like core of the disc between C4 and C5 in the neck, sitting slightly behind the disc's centre inside a ring of tough fibres.

What it does

Mostly water held in a gel; it spreads load evenly across the vertebrae and acts as the pivot on which this level bends.

Keeping it well

A bulge at C4–C5 can pinch the C5 nerve, giving pain or tingling in the shoulder and outer upper arm, with weak arm lifting. Weak or clumsy hands and legs mean cord pressure and need prompt review.

Related conditions

• Axial spondyloarthritis
• Bone metastases and spinal cord compression
• Cauda equina syndrome
• Gout
• Haemophilia & bleeding disorders
• Herniated disc
• Lyme disease
• Marfan syndrome & connective tissue disorders
• Neck pain and cervical spondylosis
• Non-specific low back pain
• Osteoarthritis
• Psoriatic arthritis
• Rheumatic fever & rheumatic heart disease
• Rheumatoid arthritis
• Sciatica
• Scoliosis
• Spina bifida & neural tube defects
• Spinal cord injury
• Systemic lupus erythematosus
• Temporomandibular joint disorder