Mnemonic

Carpal Tunnel Contents - 9 Tendons and 1 Nerve

A memory aid for the ten structures passing through the carpal tunnel.

Expansion

Four flexor digitorum superficialis tendons, four flexor digitorum profundus tendons, one flexor pollicis longus tendon and the median nerve

Mnemonic

“9 tendons and 1 nerve”, counted as 4 + 4 + 1 + 1:

  • 4 - flexor digitorum superficialis
  • 4 - flexor digitorum profundus
  • 1 - flexor pollicis longus
  • 1 - median nerve

The ulnar nerve and artery run in Guyon’s canal, superficial to the retinaculum, so they are outside the tunnel and spared in carpal tunnel syndrome.

Expansion

  • 4 - flexor digitorum superficialis tendons
  • 4 - flexor digitorum profundus tendons
  • 1 - flexor pollicis longus tendon
  • 1 - median nerve

That is 9 tendons + 1 nerve = 10 structures. Flexor carpi radialis has its own compartment and is not counted inside the tunnel proper.