Third lumbar vertebra

Looks like

A lower-back vertebra (L3) with the longest side processes of the lumbar spine.

What it does

Carries weight and anchors deep back and flank muscles.

Keeping it well

Muscle mass at L3 on CT is used to measure muscle loss (sarcopenia). The L3–L4 gap can be used for a spinal tap.

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