Watching an awake patient move the wrist during WALANT wrist arthroscopy provides information not available from MRIs or from a sedated patient. It can be more useful as both a diagnostic and a therapeutic tool.

Intraoperative active motion of the wrist can give you better information about the degree of ligament injury in situations such as a scapholunate or lunotriquetral injury. A cooperative, pain-free patient provides an “active” Geissler evaluation.1

By performing dry or wet wrist arthroscopy using WALANT, patients can participate in the diagnosis and decision-making. This enhances their ability to take an active part in their treatment.

You do not infuse water into the joint in dry wrist arthroscopy. This has advantages that make it valuable in diagnostic arthroscopy.2 WALANT works well for this technique. The advantage with WALANT in dry arthroscopy is that detailed imaging of the wrist may be obtained to both diagnose and educate the patient during surgery.

All of the general advantages listed in Chapter 2 apply to both the surgeon and the patient.

See Chapter 1, Atlas, for more illustrations of the anatomy of diffusion of tumescent local anesthetic in the forearm, wrist, and hand.

It is important to block the nerve branches innervating the dorsal wrist capsule so you can access pain-free portals.

We inject patients lying down on stretchers in a waiting area before they come into the operating room to decrease the risk of their fainting (see Chapter 6).

Slowly infiltrate at least 20 to 30 ml of buffered lidocaine with epinephrine to the dorsal aspect of the wrist to block the sensory branches of the radial, ulnar, and posterior interosseous nerves.1 The infiltration should cover the area from the level of Lister′s tubercle to the carpometacarpal joints.

The goal of the injection is to bathe local anesthetic 2 cm beyond wherever you think you have even a small chance of dissecting in the wrist or forearm.

To minimize the pain of injection, start with a 27-gauge needle (not a 25-gauge) in the most proximal red dot injection point.

Ask the patient to look away. Press with a fingertip just proximal to the injection site before you put in the needle to add the sensory “noise” of pressure to decrease the pain.

Insert the first needle perpendicularly into the subcutaneous fat. Stabilize the syringe with two hands and have your thumb ready on the plunger to avoid the pain of needle wobble until the skin needle site is numb. Inject the first visible 0.5 ml bleb and then pause. Wait 15 to 45 seconds until the patient tells you that all the needle pain is gone. Inject the rest of the first 10 ml slowly (over 2 minutes) without moving the needle.

Reinsert the needle farther distally into skin that is within 1 cm of clearly vasoconstricted white skin that has functioning lidocaine and epinephrine so that needle reinsertion is pain free.

Continue injecting from proximal to distal, blowing the local anesthetic slowly ahead of the needle so there is always at least 1 cm of visible or palpable local anesthetic ahead of the sharp needle tip that the patient would feel if you advanced it into “live” nerves. “Blow slow before you go.” (See Chapter 5 for further tips on how to inject local anesthetic with minimal pain.)

Following the subcutaneous infiltration, inject at least 2 ml of lidocaine-epinephrine into the radiocarpal joint to ensure anesthesia of the volar wrist capsule if shaving manipulation of the joint proves necessary.

A technique using portal site anesthesia alone has been described, in which each portal is marked and injected with an average of 5 to 6 ml of local anesthetic.3 Blocking the entire dorsal aspect of the wrist ensures a pain-free procedure and retains the option to convert from arthroscopic to open surgery with good anesthesia and hemostasis.

We seldom use volar wrist portals. If you plan to use these, you must infiltrate subcutaneous volar anesthetic as well.4

If you are going to manipulate the palmar structures as well, you should inject an additional 10 ml under the forearm fascia between the median and ulnar nerves on the palmar side 1 cm proximal to the wrist crease.