All right the major component of the anterior thorax is your ribcage and you have to
understand that on each side you have 12 12 ribs equal 24 in all and they're very different
depending on which area from superior to inferior now I want to focus on what we refer to as a
typical rib that's usually ribs about three to ten and this one is rib eight and I want to talk about
the structures that you'll find on almost all so I have this organized how would actually be
located in the body you're going to have your sternal rib end right here that's going to be
anteriorly placed because you're gonna have costal cartilage that will extend to the sternum and then
the more complicated portion of the ribs going to be more posteriorly placed because that's what
what is actually articulating with your vertebral column so you have the head of the rib as well
as the tubercle of the rib the head of the rib is going to articulate with the body of the vertebrae
whereas the tubercle is going to articulate with the transverse process of the vertebrae now
remember back in our discussion of the vertebral column which vertebrae are actually articulating
with ribs out of the cervical thoracic and lumbar its thoracic you have 12 thoracic vertebrae 12
ribs one other thing I want to note in a typical rib you have this divot right here on the inferior
portion of the rib this is kind of a cradle for the intercostal neurovasculature so you have an
intercostal nerve artery and vein that are going to travel in this area so you have muscles here
but also the divot really helps to protect that important neurovasculature now there are some
atypical ribs that I want you to note I did not bring a twelfth rib it looks basically like a
finger there's very little curvature to it you don't actually have much cartilage associated
with it because it's not actually extending up to the sternum so we refer to that as rudimentary
rudimentary cartilage but the first two ribs I want to talk about first so here is a first rib
and you can see how curved this is in comparison to a typical rib and short and this is a second
rib so a little bit longer but also fairly short in comparison to the typical rib now the first
rib as its name would indicate is going to be the most superior of the ribs it's very well protected
so it's going to be underneath this clavicle region and closely associated with a lot of
important neurovasculature so your subclavian artery and vein as well as your brachial plexus
very closely associated to muscles are going to attach here you're going to have your anterior
scalene as well as your middle scalene so if you can see how robust this area is right here it's
because you have muscles actually attaching there now your second rib as we were talking about is a
little bit longer but still very curved you're gonna have your posterior scalene attached here
so your complex of scalene muscles are attaching to your 1st and 2nd rib now let's talk a little
bit about the costal cartilages associated with ribs we discussed this we were talking about the
sternum this is what's actually attaching to the sternum ribs 1 through 7 are going to have
their own or their individual costal cartilage so they have an individual attachment to the sternum
whereas ribs 8 through 10 are going to attach to the costal cartilage above it so kind of forming
the shared costal cartilage that heads up towards the xiphoid process of the sternum and that's
really what's going to form that costal margin that you can palpate right here ribs 11 and 12
those are going to be referred to as floating ribs and that's because their costal cartilage
which is rudimentary isn't going to extend all the way to the sternum so very important in terms of
giving your thorax a bit of flexibility which is important in terms of breathing and inspiration