Regions of the back and buttocks

If you were told that a patient presented with back pain, where would you think they were feeling pain? Here, here or here? It’s hard to know, isn’t it? All of these areas are part of the back. Clinicians use specific-named regions in the identification of injuries or pathologies to underlying structures to make their descriptions and communication with others more accurate and clear. Today, we’re going to be talking about the regions of the back and the buttocks. So, let’s get started, shall we?

So we’re going to begin our tutorial with the regions of the back working in a roughly superior to inferior direction, then we’ll get to the buttocks and identify the regions in the area. First stop, the regions of the back.

An easy region to identify is the area that we see highlighted in green, and this is the vertebral region of the back, named so because it is overlying the vertebral column. Specifically, this region corresponds to the underlying thoracic and lumbar regions of the spine and here there’s just one vertebral region right in the midline of the back.

Another region that’s named after the bone it overlies is the scapular region, and as you’ll have guessed, this region overlies the scapula. We have a right and a left scapula region where we can find some muscles of the rotator cuff and other structures related to the scapula.

Between each scapular region and the vertebral region, we find the interscapular region, and deep to the skin of this region is where we’d find the rhomboid major and minor muscles. And this fits quite well as our rhomboid muscles run between the scapulae and the vertebral column.

Also named for this relationship with the scapula is the suprascapular region, which we can now see highlighted in green and superior and medial to the scapular region. Medial to the suprascapular region is the vertebral region. Immediately deep to the suprascapular region is part of the most superficial muscle of the back, the trapezius.

The next area we’re going to be talking about is technically a region of the shoulder, but we’ll briefly mention it as we can see it from this perspective, and the region that I’m talking about is the deltoid region. This region is demarcated by the outline of the deltoid muscle, which is the muscle that forms the rounded fleshy part of the upper arm. And the deltoid region, just like the deltoid muscle, extends around the shoulder anteriorly, so what we’re observing on the back is the posterior aspect of the deltoid region.

Moving inferiorly, we see two areas highlighted in green which are the lateral pectoral regions, and this region also has an anterior aspect which is covered in our tutorial on the regions of the thorax and the abdomen. So for now, let’s focus on the posterior part.

The posterior aspect of the lateral pectoral region has two medial boundaries, the first of which is formed by the scapular region and the second of which is formed by the infrascapular region. And this region also has a superolateral boundary which is formed by the axillary region of the upper limb. So let’s take a closer look at that medial boundary of the posterior part of the lateral pectoral region.

So what we can see highlighted now is the infrascapular region and again it’s nicely named for its relationship with the scapula as it sits inferior to it. Its superior border meets the interscapular region and between the two infrascapular regions, we have the vertebral region. Immediately deep to the skin in this region is part of the latissimus dorsi, and note of this muscle underlies many regions of the inferior portion of the back.

So the next two structures that we’re going to be talking about are triangles. So, the superior lumbar triangle, also known as the triangle of Grynfeltt-Lesshaft is bound by three structures. Its superior border is formed by the twelfth rib, its lateral border is formed by the internal oblique, and its medial border is formed by quadratus lumborum muscle. And the superior lumbar triangle is an anatomical space through which lumbar hernias can occur.

So now were looking at the inferior lumbar triangle which is also known as Petit’s triangle. And again, this region has three boundaries that are formed by three different structures. So, its medial boundary is formed by the latissimus dorsi, its inferior boundary is formed by the iliac crest, and lastly, its lateral boundary is formed by the external oblique. Like the superior lumbar triangle, the inferior lumbar triangle is a space through which lumbar hernias can occur.

The final region of the back that were going to be looking at today is the sacral region, and we can see this now highlighted in green. It’s situated just above the buttocks and at the base of the spine inferior to the vertebral region. And this region essentially consists of the area that overlies the sacrum.

Alright, so those are all the regions of the back. Let’s now move on to the regions of the buttocks starting with the gluteal region.

The gluteal region encompasses the area that is more commonly referred to as the buttocks. The gluteal region extends from the iliac crest to the gluteal fold and is considered to be a transitional region between the trunk and the lower limbs. Superiorly in the midline, the gluteal region is next to the sacral region. It contains three gluteal muscles, the largest of which, the gluteus maximus, we can see highlighted in this image, and it also contains some lateral rotators of the thigh.

In our next image, we can see the intergluteal cleft that’s highlighted in green, and the intergluteal cleft is the groove between the buttocks that runs from the inferior border of the sacrum to the perineum. Situated deep to the intergluteal cleft, we find the last region of the buttocks that we’re going to be talking about today, and this is the anal region. And this region comprises of the anus and the surrounding skin.

Okay, so that brings us to the end of our tutorial today. Before I let you go, let’s have a quick review of what we looked at.

So, first, we focused on the regions of the back which included the vertebral region in the midline overlying the vertebral column and the scapular region overlying each scapula, and between this scapular region and the vertebral region is the interscapular region. Superior to each scapula and interscapular region is the suprascapular region, and moving laterally, we found the deltoid region overlying the deltoid muscle.

Inferior to that was the posterior part of the lateral pectoral region which, remember, also has an anterior part, and moving medially we found the infrascapular region which is located inferior to the scapula. Next stop were the superior and inferior lumbar triangles which are vulnerable to herniation, and finally, we looked at the last region of the back – the sacral region – which overlies the sacrum.

We then moved on to the regions of the buttocks where we looked at the gluteal region which contains the gluteal muscles and the intergluteal cleft which runs from the inferior border of the sacrum to the perineum. Deep to the intergluteal cleft, we found the anal region which comprises the anus and the surrounding skin.

So, that brings us to the end of our tutorial on the regions of the back and the buttocks. I hope you found it useful. Thanks for watching. Happy studying!