RASL stands for reduction and association of the scaphoid and lunate, and the goal is to recreate an association between the two bones (scaphoid and lunate) with a bony or fibrous link. Biomechanics are not restored but are more physiological than the alternative procedures (Blatt dorsal capsulodesis, scapho-trapezoideo-­trapezial arthrodesis, Brunelli standard or modified).

The indications are subacute ligamentary repair (stage III and IV as described by Garcia-Elias et al. [5]). This means reducible, dissociative instability with good ­cartilage quality. Contraindications for this operation are pre-existing arthrosis whether radio-carpal or between scaphoid, trapezoid and trapezium. Radio-styloid arthritis is not a contraindication.

The technique described by Faithfull et al. is based on a dual incision dorsal and radial in a longitudinal way. The dorsal incision is for the actual surgical procedure; the radial approach is used to perform the styloidectomy and insert the headless compression screw (Herbert, HCS, etc.).

The dorsal approach is a 3–4 extensor compartment incision with a U-shaped distally based flap of the capsule. Other approaches described by Berger and Bishop are also possible [2]. Inspection of the scapholunate gap and quality of the cartilage is performed, and placement of two 1.5-mm K-wires in the distal radial portion of the lunate and the distal ulnar portion of the scaphoid is performed to act as joysticks. Care is taken to place the K-wire in a maximal divergent angle in order to correct the instability by clamping both K-wires together with a Kocher [7]. With a knife, we perform the sharp removal of the ligament remnants, and we remove with a bur and rongeur the cartilage until cancellous bone is exposed.

With the radial approach, the styloid is removed through the first extensor compartment, which is reclined in a volar way. After resection of the styloid, exposure of the scaphoid is realised. The removal of the styloid diminishes the impingement of the scaphoid, eases the insertion of the bone screw and can also enhance the results by removal of degenerated articular surface of the styloid of the radius.

Afterwards, a reduction of the scaphoid and lunate is performed with the joysticks by clamping them with a Kocher; a K-wire is placed between scaphoid and lunate from radial to ulnar, slightly distal to the mid-waste of the scaphoid taking care not to penetrate the midcarpal joint space. The cannulated bone screw (Herbert) is inserted from radial to ulnar under image intensifier.