Now that we’ve looked at the extrinsic muscles and the intrinsic muscles of the hand, let’s see how they all fit together. This can be a review session, if you’d like to turn off the sound.
Here’s the hand with all the muscles and long tendons present. On the back, here are the tendons of extensor digitorum, extensor indicis, and extensor digiti minimi.
Deep to the extensor tendons are the interossei. Here’s the tendon of extensor pollicis longus, and brevis, and abductor pollicis longus.
On the front, here’s the palmar aponeurosis, which we’ll remove. Here are the tendons of flexor digitorum superficialis, and profundus, and here’s one of the lumbrical muscles.
Here’s flexor pollicis longus, surrounded by flexor pollicis brevis. Here are abductor pollicis brevis, and deep to it, opponens pollicis. Here are abductor digiti minimi, together with flexor digiti minimi, and deep to them opponens digiti minimi.
We’ll remove the flexor tendons, to see adductor pollicis, and the interossei. The three most radial interossei lie here, behind adductor pollicis.