(ON THE LEFT SIDE ONLY) Expose and identify the deep muscles of the anterior compartment of the forearm. (G 2.66B;N 434;Gl 26.10C) You will be keeping superfical forearm and hand structures intact on the right side.

1. Return to the median nerve at the cubital fossa. Blunt dissect along the median nerve where it passes between the two heads of the pronator teres muscle.
   (ON THE LEFT FOREARM ONLY) Sever the more superficial head parallel to the course of the median nerve and reflect this head back toward its proximal attachment (medial epicondyle of the humerus)  .
2. Trace the median nerve until it passes deep to the flexor digitorum superficialis (FDS) muscle. (G 2.64B;N 433;Gl 28.37) Blunt dissect under the flexor digitorum superficialis and sever (ON THE LEFT FOREARM ONLY) the FDS muscle from the radius parallel to the course of the median nerve.   Leave the humeral attachment of the FDS intact. Isolate the four tendons of the flexor digitorum superficialis muscle.
   (ON THE LEFT FOREARM ONLY) Sever the tendons near the wrist. Make sure you do not sever any arteries or nerves or underlying tendons. Reflect the flexor digitorum superficialis muscle toward its radial attachment (leave this attachment intact).
3. Identify and clean the flexor digitorum profundus muscle and its tendons. Tug on the tendons and observe which fingers flex.
4. Identify and clean the flexor pollicis longus muscle and its tendon. Tug on this tendon and verify that the thumb flexes.
5. Blunt dissect between the flexor pollicis longus tendon and the adjacent flexor digitorum profundus tendons and identify the pronator quadratus muscle.
6. Identify and clean the ulnar artery and nerve between the tendons of the flexor carpi ulnaris and flexor digitorum profundus muscles. (G 2.65B;N 433;Gl 28.37C)