For accurate portal identification, marking on the skin should be done after the arm
has been put in traction. It is helpful to outline the major dorsal veins with the
marking pen before putting the hand in traction so that portal placement does not
injure a dorsal vein. After the arm is put in traction, first Lister’s tubercle is palpated
and marked on the skin. Next, the ulna styloid, the approximate distal edge of the
ulna and the ECU tendon are marked, as well as the radial styloid.

The 3-4 portal is marked directly distal to Lister’s; a dimple can be palpated as the
surgeon runs his thumb from Lister’s tubercle distally. Next, the approximate location
of the 6R portal is outlined. Note that the 6R portal marking should lie a few
millimeters proximal to the 3-4 portal marking because of the inclination of the distal
radius articular surface. Finally the radial mic-carpal and ulnar mid-carpa portals are
marked 1 cm distal to the 3-4 and the 4-5 portals, respectively.

After marking the portals, the Joint is insufflated with saline. A 22G needle over a
20cc syringe is introduced at the side of the 3-4 portal in a dorsal distal to proximal
volar direction matching the 11° volar inclination of the distal radius. This needle
verifies correct marking of the 3-4 portal and, if the position is correct, the radiocarpal
joint can be filled with 7 to 10 mm of saline. At this point the distended joint can be
palpated distal to Lister’s (instead of the dimple previously palpated). Next the skin
only is incised with an 11 blade. The subcutaneous tissue is bluntly dissected all the
way to the capsule with a small curved hemostat (mosquito clamp). The direction of
the curvature of the hemostat should match the 11° volar inclination of the distal
radius. The dorsal capsule offers appreciable resistance to blunt dissection and,
when it is penetrated, the saline pops out of the portal verifying correct articular
entrance.

The exact same technique is used for creation of the radial mid-carpal portal; needle
placement, saline insufflation, blunt dissection with a mosquito but the mid-carpal
joint is usually more difficult to pinpoint. If difficulties are encountered, the above
steps are repeated trying to follow the exact trajectory of the initial needle entering
the joint.

The 6R portal is created with the outside-in technique. Under direct vision of the TFC
with the scope pointing to the dorsal periphery of the TFC a 22 ??G needle is
inserted at the side of the marked 6R portal. The needle should enter the joint just
distally to the dorsal periphery of the TFC attachment to the capsule. The position of
the needle may need to be adjusted to have the exact entry point to the capsule.
Transillumination through the skin of the light of the arthroscope may be helpful in
finding the correct entry point. When a satisfying position is determined the surgeon
must also note the angle at which the needle was inserted. Then, a skin incision
within an 11 blade is performed and the subcutaneous tissue is bluntly dissected
with a mosquito and the entry to the joint is accomplished.

The skin incisions for the portals can be created either in a longitudinal or a vertical
(along Langerhans lines) fashion with longitudinal being safer for the nerves and
tendons. They may not be bigger than a few millimeters as the arthroscope is only
2.7 mm wide. Creating too large portals makes keeping the pressure in the joint
more difficult. On the contrary, if one chooses to perform dry arthroscopy the portals
should be larger to accommodate entrance of larger instruments to keep the joint
dry. In any case, it is highly important not to go deeper than the dermis with the
scalpel in wrist arthroscopy (unlike the knee or the shoulder).