There are several portals described for wrist arthroscopy. They are generally named
from the corresponding interval between the extensor tendon compartments at the
wrist. Although there are several possible portals, in everyday practice three or four
are used. There are mainly viewing portals, used for arthroscope introduction to the
joint or mainly working portals used for instrument and sutures introduction.
Starting from radial, the 1-2 portal corresponds to the interval between the 1st and
2nd dorsal compartments and is used mainly as a working portal for arthroscopic
styloidectomy. Blunt dissection after skin incision is imperative, as the dorsal branch
of the radial artery can be injured during portable placement.
The 3-4 portal is created directly distal to Lister’s tubercle and is the main viewing
portal of all procedures. By moving the arthroscope to another portal it can be used
as a working portal for the scapholunate iinterval and to remove dorsal ganglia.
The 4-5 portal is a poorly defined portal as the interval between the 4th and the 5th
compartment is not easily palpable and there are no osseous landmarks. It is a
working portal and it is used when access radial to the 6R portal is required and
should be always created bluntly so that the small extensor digiti minimi tendon is
not injured
The 6R portal is situated on the radial side of the extensor carpi ulnaris (ECU)
tendon. It is, in our practice, the main working portal. It is marked on the skin prior to
the beginning of the procedure but its position is verified with a needle with an
outside-in technique under direct vision with the arthroscope from inside the joint. It
should enter the joint just distal of the dorsal attachment of the FCC to the
capsule.This portal gives access to the TFC and the lunotriquetral ligament.
The 6U portal is situated ulnar to the ECU and was used as an outflow portal when
arthroscopic pumps were not in use and gravity flow was used for inflow. Nowadays
it is used for access to the base of the ulnar styloid and the prestyloid recess.
The radial mid-carpal portal is situated one centimeter distal to the 3-4 portal.It is
used as a viewing portal for the mid-carpal joint and corresponds to the junction
between scaphoid lunate and capitate.
The ulnar mid-carpal portal is situated one centimeter distal to the 4-5 portal. It is
marked on the skin but its position is verified with the needle and the outside-in
technique under direct vision with the arthroscope. It is the main working portal for
the mid-carpal joint.
Other less often used portals include:
The direct distal radioulnar joint (DRUJ) portal, which is created a few millimeters
approximal to the 6R portal and puts the arthroscope under the TFC. Due to the fact
that this is a very small space the 2.7 mm arthroscope can be used in larger built
patients, whereas in smaller built patients the 1.9 mm arthroscope can be used.
Verification of the position of this portal can be accomplished with a needle that is
introduced under the TFC and can elevate the central disc under arthroscopic vision
from the radio carpal joint.
The accessory 6R portal is created one centimeter distal to the 6R portal and is
used to insert instruments at an angle aiming at the fovea of the ulna during foveal
TFC reattachment.
Finally, a volar radial portal has been described, which is created open with a 2-3
centimeter incision over the distal flexor carpi radialis FCR tendon. After opening
the superficial part of the FCR sheath and retracting the tendon radial or ulnar, a
needle is directed towards the joint through the floor of the sheath. The needle
should be visible with radio carpal arthroscopy inserting the joint between the volar
radiocarpal ligaments (radio-scapho-capitate, long and short radiolunate ligaments)
in order to avoid injury to the median nerve or the radial artery.