[Music] in this lesson I'm going to describe some of the key structures that are seen in the palm particularly the superficial structures of the palm so let's start by looking at a Palmer view of the right hand and one can see the palm as well as the various digits there are two elements of the hand and the more proximal part known as the thenar and hypothenar eminence --is as seen here as well as seen here the thenar eminence is the area at the base of the thumb whereas the hypothenar eminence is the area at the
base of the little finger and these are quite prominent because of certain muscles that are in this in these locations the hand can be divided into two parts through a line going down the middle of the ring finger as seen here that divides it into a 1.5 or one and a half digits on the other side and then the remainder of the three-and-a-half digits on the more radial side the ulnar nerve supplies these 1.5 digits that is the little finger as well as one half of the ring finger as seen here so this is the
ulnar nerve and it's coming down the ulnar side of the wrist crosses into the hand and then it divides into what are known as digital branches as seen in the diagram there are two digital branches in each digit one that runs down the medial side of the digit and one that runs down the lateral side of the digits the ulnar nerve supplies both sides of the little finger and it supplies the medial or other side of the ring finger the other nerve which is in this location is the median nerve and it runs down through
the carpal tunnel and it divides into multiple digital nerve branches as shown here in the diagram and therefore the radial or lateral side of the ring finger along with both sides of the middle finger the index finger and the thumb are supplied by the median nerve this is the classic distribution of innervation of these two nerves into the palm there are some anatomical variations where a little larger area may be supplied by the median nerve or the same may be true with a little larger area being supplied by the ulnar nerve there's a final small
part that is seen at the base of the thumb that is innervated by the radial nerve as seen here much larger portions of the dorsum of the hand is supplied by the radial nerve but there's often a small part that will creep on to the palmar side and is often seen in the base of the thumb area as shown in the diagram let's now review the blood supply of the hand and in order to do that we have a simple line drawing that depicts the skeleton along with the outer covering the skin of the palm
and the digits and the ulnar artery is one such artery that supplies the hand coming down the other side of the wrist as shown here and it is joined by the radial artery on the other side as shown here both of these the ulnar and radial arteries divided into a superficial and a deep branch and the superficial branches unite to form the superficial Palmer Orange which is seen here note that the major contributor to the superficial Palmer arch is from the ulnar artery sometimes this arch may be incomplete and there is a fair amount of
anatomical variation in terms of the extent and the contribution between the two arteries likewise the deep branches both from the ulnar and the radial arteries also unite to form the deep palmar arch as seen here and in this arch it is primarily the radial artery which participates in its formation again there is a fair amount of anatomical variation in how these arches are formed and whether they are complete or incomplete this both of these arches are excellent examples of what we call as anastomosis where arteries come together and have a joint blood supply and they
actually mix meet up with each other the superficial arch and the palmar arch both of them supply the rest of the hand by dividing into multiple smaller branches the superficial palmar arch gives off several branches typically somewhere between three to five and these run down the hand and then divide into what are known as digital arteries and run with the digital nerves on either side of the digits so there's one for the ulnar side of the digit and one for the medial side similarly the deep palmar arch also gives rise to a number of smaller
branches but primarily the branches running to the thumb come from the deep arch and in this way there is a very rich supply of blood and this can often be altered based on environmental circumstances whether there's exposure to cold or hot weather or other such environmental conditions let's now look at a superficial dissection of the palm of the hand and we have removed the skin and we have removed some of the superficial connective tissue to clean out this area and show some of the deeper structures quite clearly the first structure that is seen here is
this flat triangular structure known as the palmar aponeurosis this is a connective tissue structure that sits in the middle of the palm and provides for attachment of some of the other structures it also is a location where this skin is finds firm attachment system of the deeper structures we see a group of muscles at the base of the thumb which forms the thenar eminence which is seen right here in this area and these are known as the thenar group of muscles likewise you have the hypothenar eminence at the base of the little finger and these
muscles are known as the hypo thenar group of muscles note some of the key neurovascular structures that are crossing from their forearm across the wrist and entering into the hand the first one of these is the artery on the ulnar side known as the ulnar artery which is seen here it is accompanied by a nerve the ulnar nerve which lies right adjacent to it over here both of these cross from the forearm across the wrist into the hand outside the carpal tunnel and are seen very clearly in this dissection the other nerve that we can
see more towards the center of the wrist is the median nerve which is seen here and note that it is entering into the carpal tunnel and goes out of view at the point of the carpal tunnel location the final structure in this area is the radial artery which is seen here and this is the other artery that has supply into the wrist and hand area [Music]
