Ligamentum flavum

Looks like

Short yellow bands of elastic tissue joining the bony arches of neighbouring vertebrae, from the second neck vertebra down to the sacrum. They form the back wall of the spinal canal.

What it does

Their stretch holds the spine upright and pulls it back from bending; being elastic, they do not buckle into the canal when you stand straight.

Keeping it well

With age they thicken and fold inwards, a main cause of lumbar spinal stenosis (leg pain on walking, eased by bending forward). Surgeons remove part of them to free the nerves. The needle for an epidural passes through them; the loss of resistance tells the doctor it has gone through.

Related conditions

• Axial spondyloarthritis
• Bone metastases and spinal cord compression
• Gout
• Haemophilia & bleeding disorders
• Lyme disease
• Marfan syndrome & connective tissue disorders
• Osteoarthritis
• Psoriatic arthritis
• Rheumatic fever & rheumatic heart disease
• Rheumatoid arthritis
• Scoliosis
• Spina bifida & neural tube defects
• Spinal cord injury
• Spinal stenosis
• Systemic lupus erythematosus
• Temporomandibular joint disorder