 Good day everybody. Dr. Sajja Sanyal, professor of department chair. This is going to be a demonstration of the wrist and the palm especially the neuro-muscular structures and some muscles. This is supine cadaver. This is the left side. I am standing on the left side and the camera person is also the left side. So we have dissected out this portion of the palm. So let's first identify the structures. We can see this tendon here. This is the flexor carbide radialis. In this particular cadaver, we don't have the palm wrist longest. We see this tendon here. This is the flexor digitorum superficialis. Under that, we can see this is the flexor digitorum profundus. This is the flexor polisus longus. This is the flexor carbide ulnaris. This is the radial artery. This is the median nerve. And further, immediately, we can see this is ulnar artery and this is the ulnar nerve. Ulnar artery is lateral to the ulnar nerve. Both of these are located under the cover of the flexor carbide ulnaris and we have separated them out. Just like the radial artery is located under cover of the radialis and we have separated them out. So let's take a look at some important landmarks and some important distributions. This place where my finger is located, this is called the carpal tunnel. The carpal tunnel is bounded by a tough ligament structure and we have already cut it here. This is the flexor reticulum and if you look very closely and we zoom the camera, we can see that this is the cut edge of the flexor reticulum on the radial side. Likewise, we can see that this is the cut edge of the flexor reticulum on the ulnar side. This is the cut edge on the other side. So therefore, this was the bridge of the carpal tunnel and we have cut it. So one cut it is here, other cut it is here. And we have opened up the carpal tunnel. Passing through the carpal tunnel, we have the following structures. We have the median nerve, which we saw just now. Then we have the four tendons of the flexor reticulum superficialis and the four tendons of the flexor reticulum profundus. And we have the flexor policies along this. So therefore, nine tendons with the sign of your sheets pass through the carpal tunnel and the median nerve is located in a very tight compartment where it can get compressed. And that is known as the carpal tunnel syndrome. Now I am going to put my finger deep inside and I have put my finger in a space in the palm. This space is referred to as the mid-palm space. This space is deep to the central compartment of the palm. And this is the potential space where, if there is an infection, pus can collect here. And from here, the infection can travel through the carpal tunnel as traced by my finger. And it can come under the flexor digital profundus, between the profundus and this muscle. This is the perimeter quadratus muscle. And this space is referred to as the space of parona. And the pus can then track and stop here where my finger is stopped at the profundus. So this is the space of parona. This is the carpal tunnel. This is the central compartment of the palm. That brings me to these bundle of muscles that we see here in the palm. This is the tenar muscles. They were covered by a fascia called the tenar fascia. And this is hypothera muscles, which is covered by a fascia called the hypothera fascia. So therefore, these two are located in the tenar compartment and the hypothera compartment. In the middle is an aponeurotic sheet, little bit of which is retained here. And that is known as the palmar aponeurosis. The proximal part of the palmar aponeurosis is attached to the flexor necrolum. And the distal portion has got four slips, which views with the fibrous flexor sheets of the digits. And we have removed that. And under that passes these four and four tendons of the flexor digital superficialis and the profundus. The tenar muscles are the outermost is the abductor policies previous. Then we have the opponents policies and deep is the flexor policies previous. And the counterpart on the hypothera side is the abductor digitimini. The opponents digitimini and the flexor digitimini previous. This is supplied by the median nerve. This is supplied by the ulnar nerve. Now let's take a look at the course of the median nerve. The median nerve after it has passed through the carpal tunnel, it enters the palm. And we can see it is giving the following branches. It gives a branch here. This is called the recurrent branch of the median nerve, which supplies the tenar muscles. Here the recurrent branch is quite superficial. And if a person falls on his outstretched hand and if he gets a superficial cut of the palm here, it can injure the superficial branch of the median nerve, the recurrent branch, and can produce paralysis of the tenar muscles. This is a picture of tenar paralysis showing what is known as the ape thumb deformity of the semen hand. Thereafter we can see that the median nerve is giving these branches. These are the cutaneous branches, digital branches to the thumb, index finger, the middle finger, and to the radial side of the middle finger. That is one structure that we see here. We have already described the flexor digitimini profundus and the superficialus. Let's take a look at the flexor carpal ulnaris. We can see that it is stopping here. This bone is the pissiform bone. And from there there is a tendon which runs and gets attached. To the hook of hamate and that is known as the pisohamate ligament. We notice that ulnar artery and ulnar nerve, they run superficial to the flexor retiniculum. And for that I will again show you the flexor retiniculum more clearly. So we notice that ulnar artery here and ulnar nerve, they are located superficial to the flexor retiniculum and I have lifted up the cut edge of the flexor retiniculum on the medial side. So therefore these two structures do not get compressed in carpal tunnel syndrome unlike the median nerve. And we see that the ulnar artery, it forms a superficial pommel arch. And from the superficial pommel arch we have the common and the proper digital arteries. Let's take a look at the ulnar nerve itself. We can see that the ulnar nerve is giving a branch which goes posteriorly and supplies the hand on the ulnar one-fourth on the dorsum of the hand. And then the main ulnar nerve goes superficial to the flexor retiniculum. Here it is located in a small tunnel called the chion tunnel which is bounded by the pisipomb bone, the hook of hemate, the bolar carpal ligament which we can see here and the pisohamate ligament. And after that it comes into the palm and we can see the course of the ulnar nerve in the palm. And here again we can see when I lift up the ulnar nerve we can see it is giving branches to the ulnar nerve. On our side of the ring finger and the little finger. So this is the distribution of the ulnar nerve here. The ulnar nerve can be endured here in three different ways. One is known as the Gion Canal syndrome and I mentioned the boundaries of the Gion Canal just now. The other is fracture of the hook of hemate. And the third condition is what is known as handlebar neuropathy. When a person is riding motorcycle for long duration it presses on the ulnar nerve. In all these situations ulnar nerve will be endured. Ulnar nerve supplies the hypothermia muscles which are shown here, which is actually the opponent's digestive enemy, abductor digestive enemy and the flexor digestive enemy brevis. Additionally the ulnar nerve supplies all the introsiae muscles. The dorsal, four dorsal, three mammary introsiae and it also supplies the lumbrical muscles, ulnar to lumbrical muscles. If the ulnar nerve is endured it will produce claw hand. When the person is asked to straighten the hand it becomes like this. This is called a radial claw hand. This is a picture of a radial claw hand which typically occurs in proximal ulnar nerve injuries. In contrast this is a picture of an ulnar claw hand which typically occurs in distal ulnar nerve regions. So this is the manifestation of ulnar nerve injury. The rule of thumb is the median nerve supplies more of the skin. It supplies lateral three folds of the palmar skin and the digital skin. And it supplies less of the muscle. It supplies only the ulnar eminence and it also supplies only the lateral two lumbricals. Ulnar nerve supplies more of the muscles. It supplies muscles of the hypothermia eminence. All the seven introsiae, the medial two lumbricals and it supplies less of the skin. It supplies only the medial one fold of the palmar skin. So these are the structures which I wanted to show you. Extending from the palm to the wrist and distally and with a respective neurovascular distribution and the clinical correlations. Thank you very much for watching. Dr. Sanjay Sanyal signing out. Mr. Ken Rolk, Amber Badge, the camera person. If you have any questions or comments please put them in the comment section below. Have a nice day.