Trapeziectomy and abductor pollicis longus suspensionplasty

Carpometacarpal (CMC) arthritis is one of the most common conditions treated by hand surgeons. Surgery is indicated in patients who continue to have severe pain or thumb dysfunction despite nonoperative management.

Patients with Eaton stage III or IV trapeziometacarpal (TM) disease have damage to the articular cartilage (see Chapter 46 , Table 46.1 ). Joint salvage procedures do not provide predictable pain relief for these patients. Surgical options for advanced disease include: (1) trapeziectomy with or without ligament reconstruction and tendon interposition, (2) arthrodesis (see Chapter 45 ), and (3) TM joint replacement arthroplasty.

Candidates for trapeziectomy and abductor pollicis longus (APL) suspensionplasty are low-demand patients with a painful, eroded basilar joint or diminished thumb function. Complete trapeziectomy is the key factor in pain relief. The APL to extensor carpi radialis longus (ECRL) tendon transfer stabilizes the thumb metacarpal base and reduces metacarpal subsidence into the trapeziectomy space.

The thumb is inspected for swelling and erythema. Resting posture is noted, paying special attention to metacarpal adduction, first webspace contractures, and metacarpophalangeal (MCP) joint hyperextension (zigzag deformity; Fig. 47.1 ).

Active and passive range of motion (ROM) and joint laxity are assessed.

Areas of tenderness around the base of the thumb are noted.

The grind test is performed by axially loading and rotating the thumb metacarpal. This motion creates pain and crepitus in arthritic TM joints because of friction between the eroded joint surfaces (see Chapter 45 , Fig. 45.3 A–B).

Objective motion measurements include radial/palmar abduction and active/passive MCP joint motion. Key pinch is recorded and compared with the opposite hand. Pinch strength is often diminished and functional hand width may be narrowed.

Patients must be evaluated for concomitant pathology. More than one-third of patients with CMC arthritis also have carpal tunnel syndrome. When indicated, carpal tunnel release should be performed at the time of CMC arthroplasty; trapeziectomy alone does not decompress the carpal tunnel. De Quervain disease, trigger thumb, and flexor carpi radialis (FCR) tenosynovitis all present with pain at the base of the thumb and must be ruled out.

Standard three-view (posteroanterior, oblique, and lateral) hand radiographs are mandatory. True anterior-posterior (Robert’s) and lateral (Bett’s) views of the TM joint are also useful ( Fig. 47.2 ).

Radiographs guide surgical decision making; however, findings do not always correlate with patient symptoms. The decision to proceed with surgery is based on the patient’s level of discomfort and dysfunction, not imaging.

The thumb CMC joint is a semiconstrained saddle joint supported by 16 surrounding ligaments. The beak ligament is the key stabilizer of the TM joint. It serves as a pivot point during pronation and prevents dorsoradial dislocation of the metacarpal base (see Chapter 46 , Fig. 46.3 A–B).

The APL tendon lies within the first dorsal compartment and inserts on the radial aspect of the thumb metacarpal base.

The FCR tendon is located just ulnar to the radial artery in the distal forearm. The tendon enters a fibro-osseous tunnel just proximal to the trapezium, then turns and inserts on the index metacarpal base. Small slips of the FCR tendon also insert onto the middle metacarpal base and the trapezial tuberosity. Care must be taken to avoid injury to the FCR during trapeziectomy.

The deep branch of the radial artery passes across the anatomic snuff box over the scaphotrapezial (ST) joint, then into the hand between the two heads of the first dorsal interosseous muscle. It runs volarly between the heads of the adductor pollicis muscle to become the deep palmar arch. The deep branch of the radial artery must be identified and protected during a dorsal approach to the TM joint. The deep palmar arch gives off a small branch to the volar aspect of the ST joint that should be identified and secured during the operation ( Fig. 47.3 ).

Branches of the superficial sensory radial nerve (SSRN) run in the subcutaneous tissue adjacent to the first dorsal compartment and along the dorsal thumb. Traction injury or inadvertent division of nerve branches can lead to persistent pain at the incision Fig. 47.4 .

For additional information, see Chapter 46 .