Neurovasculature of the Posterior Compartment of the Arm

00:01 So now, let's have a look at that in a little bit more detail when we look at the relationship of triceps to its neighboring structures.

00:08 So, again, we have some muscles included here. We can see triceps brachii nicely indicated.

00:13 Here we can see the various scapulohumeral muscles, so, supra infraspinatus, deltoid and teres minor, teres major all been included to form the substance around the shoulder joint.

00:24 And you can see how triceps is intermingling amongst those.

00:28 If we look at deltoid, we could see, we've got the middle and posterior heads covering superficial to the various heads of triceps.

00:37 If we remove those, we can see the origin of the medial and lateral head of triceps coming from the humerus.

00:44 But importantly, here, we can see the longhead and how it interacts within the scapulohumeral muscles, specifically, teres major and teres minor.

00:54 And remember that the long head forms an important division between a couple of spaces in this region.

01:00 So, the long head is forming the lateral boundary of the triangular space where teres minor and teres major formed the superior and inferior boundaries respectively.

01:12 And the long head of triceps brachii is forming the medial boundary of the quadrangular space with teres minor and teres major, again, forming the superior and inferior boundaries respectively with the humerus now forming the lateral boundary.

01:30 The final space is the triangular interbowl. This is important whether the radial nerve comes through.

01:36 But the longhead is forming the medial boundary of this space and the humerus is forming the lateral boundary with the teres major muscle forming the superior boundary. This triangular interval is an important space as it allows the profunda brachii artery and the radial nerve to pass through.

01:54 Remember, the radial nerve then runs down the radial groove of the humerus, separating the medial from the latera heads of the triceps brachii.

02:03 And here, we can see in slightly more detail.

02:06 We've got profunda brachii artery and the radial nerve passing through the triangular interval to supply the posterior compartment of the arm.

02:16 So, there's a whole series of important muscles situated in both the anterior and posterior compartments of the arm and they have a very important neurovascular relationships to them as well.

02:27 And hopefully, you can remember all of these from this lecture.