 Hi, I am Dr. Bipin Chha, I am a senior consultant radiologist with special interest in the musculoskeletal imaging. I have been immediate past president of musculoskeletal ultrasound society of India and I am practicing radiologist in Aklat polyclinic and imaging center at Vileparla West. Today I am going to demonstrate the normal ultrasound technique for the examination of the wrist using the high frequency ultrasound machines and the probe. For the ultrasound examination of the wrist joint I prefer to use hockey stick probe with the high frequency which is ranging in 8 to 18 megahertz. If this probe is not available one can go for a linear high frequency probe which has a range of 6 to 16 megahertz either of this probe provide a good quality of imaging which are enough for the diagnostic purpose. Examination of the wrist is performed in a systematic manner using the protocols which are suggested by the European society of skeletal radiology. The examination begins by evaluating the periarticular soft tissue structure on the dorsal aspect then moving on the ventral aspect and the dynamic examination can be performed either in the ulnar deviation or radial deviation or in the position between the supination and pronation or in the complete pronation. When you need to test the integrity of the tendons or the movements of the nerves one can keep the gel tube under the wrist and ask the patient to perform actively the flexion and extension of the fingers or one can do the passive flexion and extension of the fingers to detect the excursion of the tendons and the nerves. The dorsal wrist examination involves evaluation of the periarticular structure which includes the 6 extensor compartment along with its tendons within it. Then we look at the scapholunate ligament we look at the distal radio ulnar joint and also we look at the dorsal recess which is the recess between the radiocarpal and the midcarpal joint. Now when we do a musculoskeletal ultrasound we start by examination of our bony anatomical landmarks. So the bony anatomical landmark which is used on the dorsal aspect of the wrist is the lister tubercle which is the bony projection in the distal radial metaphysis. The lister tubercle divides the extensor compartment 2 which is on the radial aspect from the extensor compartment 3 which is on the ulnar aspect. Once you have identified the lister tubercle you move your transducer toward the radial side you look at the tendons of the compartment 2 then you move more radially and look at the tendons of the compartment 1 once that is being done. Now coming back to our bony acoustic landmark of the lister tubercle we move on the radial side and look at the tendons of the compartment 1. To visualize this tendons we ask the patient to keep the arm in a midway between the supination and pronation and keep the transducer along the radial styloid process. Once we keep the transducer along the radial styloid process we look at the two tendons of the compartment 1 which includes the abductor policies longest and extensor policies bravest. This tendons then to be followed all the way distally till its attachment to the respective bones. So, those are the tendons of the compartment 1. Once you have identified this tendons you have to move your transducer proximally and till you reach the musculotendinous junction. So compartment 1 is cross compartment 2 tendons proximally at the level of the intersection. So, that is the level of the intersection. The examination of the tendons is performed in a short axis or in a transverse view which are the most informative. The longitudinal views are not that informative but once you recognize the pathology you need to turn your transducer 90 degree and look at the tendon in a longitudinal plane where it appears typically the hyperequic fibrillary pattern because of the collision fibers which appears bright and the supportive connectivity issue appears dark. There are two important anatomical variations that one can encounter in the compartment 1. The first one is the multiple tendon slips of the abductor policies longest which are seen attaching to its distally to its bony attachment. The second one is the vertical septum dividing the tendon shear into two halves and harboring each tendons in each compartment. While examining compartment 1, one can also look at the two important structure. One is the radial artery on the ventral aspect of the compartment and another is the sensory branch of the radial nerve which crosses from the ventral to the dorsal aspect of the compartment 1. After finishing the examination of compartment 1, we come back to our original landmark that is the bony acoustic landmark of the Lister tubercle and move our transducer on the radial aspect to examine the extensor tendons of the compartment 2 that is extensor, carpe radial is longest and extensor carpe radial is bravest. So once the tendons of compartment 2 are identified, you move your transducer proximally and look at the cross section of the compartment 1 over the compartment 2 tendons and then again move distally from the Lister tubercle and look at the tendon of the extensor policies longest which traverses on the superior aspect of the compartment 2 that is the distal intersection. Again as I said earlier after examination of the tendon in a short axis or a transverse axis we turn our transducer 90 degree and look at the tendon in a longitudinal plane and recognize the typical fibrillary pattern of the tendon. Once examination of the compartment 2 is over, you move on the ulnar aspect of the wrist and identify the tendon of the compartment 3 that is the extensor policies longest and you can move your transducer proximally till you reach the musculotendinous junction and then you move transducer distally from the distal tubercle and check the crossing over of this tendon over the compartment 2 tendons and reaching to its attachment over the distally to the base of the distal phallings of the thumb. From the compartment 3 examination we moved towards the ulnar aspect and look at the tendons of compartment 4 which is the extensor digitorum communis and extensor indices properoses. Then you look at the tendon of the extensor digiti minimi overlying the distal radio ulnar joint and that is compartment 5 and then you move over the ulnar aspect and keep your transducer over the ulnar grove and look at the tendon of the compartment 6 that is the tendon of the extensor carpe ulnaris. In order to identify each tendons of the finger, we need to do a dynamic examination. To achieve this, you need to keep the wrist of the patient on gel tube or some pad to elevate the wrist and ask the patient to do active flexion and the extension of each finger. So, by looking at this we can look at the different tendons and identify each tendon of the fingers. Dynamic examination of the compartment 5 tendon is performed by asking the patient to move a little finger up and down which shows the movement of the tendon lying over the distal radio ulnar joint. In order to identify the tendon of compartment 6 that is the extensor carpe ulnaris, ask the patient to do a radial deviation of the wrist and look at the bony profile of the styloid which shows the ulnar grove. The tendon is seen lying just about the ulnar grove and bounded superiorly by the ulnar retinaculum which appears as a hypoeconomic structure. From the transverse axis, one needs to move on the longitudinal plane to identify the extensor carpe ulnaris tendon in a long axis and one also can appreciate a gap between the styloid process of ulnar and the radius which is occupied by the peripheral portion of the TFCC. One also can recognize there is a space between the epiphysis and the metaphysis in this immature subject which appears as a defect. After finishing the examination of extensor compartment tendons, one need to look at this K4 lunate ligament to look at the structure. We have to go back again to our reference point of the lister tubercle then move your transducer distally. Once you will lose the lister tubercle, again you will come at the two hyper-equic structure that of the lunate and the scaphoid and the scapholunate ligament bridges between these two bone. It connects scaphoid and the lunate and appears as a hyper-equic structure. This is the dorsal component of the U-shaped scapholunate ligament. By moving the wrist in the ulnar deviation, the scapholunate and lunotriquetral ligament can be well identified at a taut structure. So if there is any tear, one can appreciate this better on the high resolution ultrasound. So ulnar deviation is very important maneuver to look at this two ligaments along its entire length. Other important structure that is examined on the dorsal aspect of the wrist includes the dorsal recess or the recess between the distal radius and the lunate which is a radio carpal recess and between the lunate and the capitrate which is a mid-carpal recess. The capitrate has got a typical appearance which looks like a peanut on the longitudinal scan. After examination of the dorsal recess, we come back again to our bony acoustical landmark of the listed tubercle and move our transducer proximally to identify the radio ulnar joint or more precisely distal radio ulnar joint by looking at the bony profile of the distal radius and the rounded profile of the ulnar. The space or a synovial space here is being very loose and in the patient with the inflammatory arthritis, the synovitis tends to occur in this area predominantly. So examination of this recess is of paramount importance to look at the synovial effusion or a synovial hypertrophy. Dynamic examination of the tendons of the compartment 1 are performed by doing the thumb movement. You need to turn your transducer 90 degree to look at this tendon in a longitudinal plane and then do a passive extension and flexion of the thumb. In patient with the decarvons disease, you are likely to see interrupted movements of the tendon. Once the dorsal wrist examination is over, patient is asked to turn the wrist and keep the dorsal of the wrist in contact with the table and the structures which are looked on the ventral aspect includes the carpal tunnel and its contents, the guan's canal and its contents and the structure which are outside the carpal tunnel which includes the flexor carpi radialis tendon and the palmaris longest tendon. For the examination of the carpal tunnel and its content, the transducer needs to keep on the palmar crease and I prefer to use the trapezoidal mode in this examination and look at the bony profile of the PC form on the ulnar aspect and the bony profile of the scaphoid on the radial aspect which marks the boundary of the proximal carpal tunnel inlet. Contents of the carpal tunnel include nine tendons which are the tendons of flexor digitorum superficialis which are four in number, flexor digitorum profundus which are again four in number and then you have one tendon of the flexor policies longest on the radial aspect and of course the most important structure that is of the median now. The flexor retinaquilum is seen connecting the PC form board to the scaphoid and it appears as a hypoequic structure because of the anisotropy since this structure runs in a oblique plate to the examination of the carpal tunnel contents. Since the contents of the carpal tunnel are situated deep and it requires more penetration I have changed the probe from the hockey stick probe to the linear probe which is of the ilion megahertz frequency now keep in mind because of the obliquity of the tendons in the carpal tunnel they are more prone to anisotropy and difficult to recognize. One need to adjust the transducer in a such a way that there is anisotropy is overcome one also needs to increase the overall gain to look at this tendons and to differentiate this tendon from the overline median now. In order to overcome the anisotropy of the tendons of the carpal tunnel one needs to toggle the transducer when you tilt the transducer the hypoequic tendons change and appear as a bright structure and can be very well visualized. The median now has got typical honeycomb pattern situated superficial to this tendon and closer to the flexor retinaquilum that marks the entry of the proximal carpal tunnel which is bounded medially by the busy form and laterally by the scaphoid bone. In order to perform or the recognize each tendon of the finger we need to ask the patient to perform the dynamic examination in flexion and extension of the finger. So once the patient does the dynamic examination each tendons of the fingers can be identified and its integrative can be evaluated to look at the distal boundary or the outlet of the carpal tunnel we need to move the transducer distally and recognize the two bony profiles that is of the hook of the hemat and the tubercle of the trapezius. So at the distal level one can identify hypoequic structure of the hook of the hemat and the tubercle of the trapezius and the contents of the carpal tunnel. The flexor retinaquilum is seen covering this tendons as a hypoequic structure and one need to go more distally and look at the diversification of the each tendons of the flexor into the each finger. Dynamic examination of the tendons of the carpal tunnel is performed by asking the patient to move fingers in flexion and extension and the excursion of this tendon is seen which is occurs very freely while the excursion of the median now is relatively less compared to the flexor tendons. In order to look at detail architecture of the median now I prefer to use again hockey stick high frequency transducer and look at the morphology of the median now which appears on a transverse view as a honeycomb pattern and when you turn your transducer 90 degree it has got typical what is called as a filamentous pattern and has got uniform diameter all the way from proximal to distal and it is seen diving distally within the carpal tunnel. Once the examination of the median now is performed at the level of the inlet of the carpal tunnel we need to move transducer more proximally and have to look at the now at the level of pronator quadratus muscle and compare the transverse section area at this level to the layer at the level of the inlet of the carpal tunnel. To look at the median now at the level of the distal carpal tunnel we need to change the transducer to a lower frequency and look at the division of the now all the way from distal carpal tunnel level to the each fingers of the hand. To recognize tender of the flexor policies longest we need to ask the patient to do a dynamic examination by doing a passive or the active moment of the thumb and one can see that there is a free moment of the tendon of the flexor policies longest on the radial aspect. After completing the examination of the contents of the carpal tunnel we need to look at the structure outside the carpal tunnel and on the radial aspect we see the tendon of the flexor carpal radial is which overlies the hyperequic structures of the scapoid. This tendon needs to be followed all the way proximally in the distal forearm till it reaches the moitendinous junction. After examination of flexor carpal radial tendon in a transverse plane we need to turn the transducer in 90 degree plane and look at the typical fibrillary pattern of this FCR tendon which is seen attaching to the scapoid. By moving the transducer on the ulnar aspect and recognizing the bony profile of the PC form we can look at the contents of the Goan's canal which contains the ulnar now adjacent to the PC form bone and the ulnar artery which is on the radial aspect of this tunnel. The ulnar now then followed distally till it divides into its branches which is a superficial sensory branch and the deep motor branch. The deep motor branch is seen lying in close proximity to the hook of the hammock and this is the area where it gets commonly injured by the traumatic injuries. The Palmer is longest tendon is seen situated outside the carpal tunnel which is seen above the flexor retina pillar like any other tendon it is seen as a hyperequic structure or has got a speckled appearance on the transverse or a short axis and the median now is seen lying deep to it just below the hyperequic flexor retina pillar. The radio carpal and mid carpal recess can also be evaluated from the ventral aspect however many times there is an issue with the penetration of the structures so one need to change to a lower frequency transducer to look at the structure as one can see here we can appreciate the radio carpal and a mid carpal recess in this relatively thin subject and also can appreciate there is a fysis between the epiphysis and distal metaphysis. Flexor tendons within the carpal tunnel needs to be examined all the way from its entry at the level of the inlet till it exits from the distal carpal tunnel level and one can see when it emerges out from the distal carpal tunnel each tendon is seen and going in the individual finger level at the level of the metacarpal head examination of wrist can be performed either in a sitting position where patient sits across the table keeping the arm on the table rest or in the supine position. I usually prefer to examine the patient in a supine position because it gives me a more flexibility during the examination both in the static as well as dynamic examination. So, this concludes the systematic examination of the ultrasound of the wrist both static examination as well as dynamic examination proposed by the protocol laid down by the European Society of Skeletal Radiology. Thank you.