It’s good to study muscles function by function, as we’ve done so far in this section, but it’s also important to see how they all overlap and fit together. If you’d like to use this next overview as a review section, turn off the sound.
Let’s look at a dissection that includes all the muscles that we’ve looked at so far, in the arm and forearm, and in the adjoining shoulder region.
Here’s the biceps, with its two heads hidden both by the deltoid, and by pectoralis minor. Here’s the short head of biceps, running close to coracobrachialis.
Running up behind biceps and coracobrachialis is latissimus dorsi. Here’s brachialis, going to its insertion on the ulna, and here’s biceps, on its way to the radius. Here’s pronator teres, crossing over from the medial epicondylar ridge to the radius.
Also arising from the medial epicondyle here are flexor carpi radialis, palmaris longus, and flexor carpi ulnaris. Here’s pronator quadratus, deep to everything. Now let's go round, and take a look at the back. Here's the triceps, with its long head going up beneath the deltoid.
Here’s teres major, and here’s latissimus dorsi again, both lying in front of the triceps. Here’s triceps going to its insertion on the olecranon. Here’s brachioradialis, going to the radius here.
Here’s extensor carpi radialis longus, and brevis, and extensor carpi ulnaris. Lying deep to all the muscles which share the common extensor tendon is supinator, all on its own.
At this point our picture of the forearm is complete as to some functions, incomplete as to others. That’s the way we’re going to leave it for now. We’ll be returning to the forearm in the next section to look at the important muscles there that we’ve not seen yet: the long muscles of the fingers, and of the thumb.