First lumbar vertebra

Looks like

The top lower-back vertebra (L1), large and kidney-shaped; the spinal cord usually ends at about this level.

What it does

Carries the upper body's weight and protects the end of the cord and the nerve roots below it.

Keeping it well

A common fracture site at the thoracolumbar junction. Leg weakness or bladder trouble after back injury is an emergency.

Related conditions

• Achondroplasia
• Acromegaly
• Cauda equina syndrome
• Fractures
• Fragility fracture
• Frailty & falls in older age
• Herniated disc
• Hyperparathyroidism
• Non-specific low back pain
• Osteogenesis imperfecta (brittle bone disease)
• Osteomalacia & rickets
• Osteomyelitis (bone infection)
• Osteoporosis
• Paget's disease of bone
• Sarcoma
• Sciatica
• Spinal stenosis
• Spondylolisthesis
• Vitamin B1, C and other deficiencies
• Vitamin D deficiency