Andrew Palmer [7] devised a classification scheme for TFCC tears that divides TFCC tears into traumatic tears, type I and degenerative tears, type II [7]. While both types of tears can be treated arthroscopically, types I-A, II-C, and II-D lend themselves to laser-assisted debridement (Fig. 3.2).

Before starting arthroscopic treatment of TFCC tears, the ulnar variance must be evaluated. This is done by taking an X-ray with the shoulder abducted to 90° and the elbow flexed to 90° with the hand flat on the X-ray cassette (the “90 × 90” view of Palmer) [8]. Triangular fibrocartilage debridement in face of an ulnar-plus variance is doomed to fail, as the simple debridement of the TFCC is insufficient to decompress the ulnar side of the wrist. In such cases of ulnar abutment syndrome, an ulnar shortening is needed. The results of TFCC debridement in patients with an ulnar-zero variance can be good, but there lingers the possibility of having to perform an ulnar shortening later. It is recommended that this possibility be discussed with the patient preoperatively. In contrast to the patient with an ulnar plus variance, the patient who presents with an ulnar minus variance is very likely to respond to simple debridement of the central portion of the triangular fibrocartilage [9, 10].

The technique of laser-assisted triangular fibrocartilage debridement is similar to that of mechanical debridement of the triangular fibrocartilage with the exception that the arthroscope can be left in the 3-4 portal while the laser is kept in the 4-5 portal. The laser is set to 1.4–1.6 J at a frequency of 15 pulses per second. With the help of a side-firing 70-degree laser tip, the triangular fibrocartilage can be very rapidly and precisely debrided. The 70-degree laser tip permits ablation not only of the radial and palmar portions of the TFCC tear, but also the ulnar and dorsal components. There is no need to bring the laser probe in through the 3-4 portal. During the debridement, care must be taken not to injure the ulnar head. This is avoided by firing the laser tangentially to the head of the ulna or passing the probe beneath the triangular fibrocartilage and firing distally. This latter technique presents minimal danger to the lunate or triquetrum, in that the fluid used to expand the joint acts as a heat sink and absorbs the laser energy as it emerges from beneath the triangular fibrocartilage. The central portion of the TFCC is debrided back to stable edges, taking care not to injure the dorsal and palmar radioulnar ligaments.

The arthroscopic treatment of the ulnar abutment syndrome is facilitated by using the Ho:YAG laser [11]. Hyaline cartilage is very efficiently removed with the laser at higher energy settings (2.0 J at 20 pulses per second). Not only are the ulnar head hyaline cartilage and subchondral bone rapidly removed, but, in contrast to burring, they are removed without producing much debris. Once the cancellous bone of the ulnar head is exposed, however, the bur becomes the most effective tool to complete the ulnar shortening. This is because it becomes very time consuming to focus the laser beam on each trabecula. During the ulnar head resection, care must be taken not to injure the sigmoid notch with either the laser or the bur. Also, care must be taken not to detach the insertion of the triangular fibrocartilage from the fovea at the base of the ulnar styloid. The successful arthroscopic ulnar shortening relies on teamwork. The assistant brings the surfaces of the ulnar head to be resected to the laser being held by the operating surgeon. By progressively supinating and pronating the forearm, an appropriate amount of ulnar head is excised. The goal is to resect sufficient ulna to produce a 2 mm negative ulnar variance. The amount of ulna resected must be verified with intraoperative fluoroscopy. Occasionally, complete visualization of the ulnar head requires that the scope be placed in the 4-5 portal with the laser entering the distal radioulnar joint through the distal radioulnar joint portal. This portal is established just proximal to the 4-5 portal and TFCC.

An effort is made to leave a smooth surface on the remaining distal ulna. The trabeculae of the distal ulna always produce a somewhat rough distal ulna at the completion of the procedure. These irregularities, however, disappear during the months following the surgery (Figs. 3.3 and 3.4). Large irregularities must be avoided, as they can catch on the proximal surface of the residual TFCC during supination and pronation.

The postoperative regimen after TFCC debridement, with or without ulnar shortening, includes providing the patient with a wrist splint to be worn as needed, as well as a home therapy program consisting of active and passive range of motion exercises. The sutures (wounds are closed using subcuticular sutures of 4-0 Prolene) are removed at 2 weeks. Strengthening exercises can be started at 6 weeks if needed. Premature resumption of heavy lifting or repetitive activities will lead to radiocarpal synovitis. Some patients feel so good after as little as 2 weeks that the surgeon must temper the patient’s desire to return to full activity. In the case of an ulnar shortening, the recovery can be as long as 6 months, as suggested by Feldon [12]. However, the majority of patients will be improved long before 6 months.