Scapholunate ligament injuries: a review of current concepts

Abstract

Injuries to the scapholunate ligament are common, especially among young active individuals. Surgeons are faced with a difficult problem because of imperfect surgical outcomes and the high demands of this patient population. Here, we review the current concepts and newest literature on scapholunate ligament injuries as well as the classification and treatment options for each stage of scapholunate instability. Emphasis is on stages in which reconstructive rather than salvage procedures can be performed. The natural history is poorly understood; it is unknown which and how many scapholunate injuries lead to wrist arthritis (SLAC wrist). Partial injuries are rare and in small studies did well with arthroscopic treatment. Complete injuries are graded based on the acuity of the injury, the presence and reducibility of scapholunate malalignment, and, finally, cartilage status. In acute injuries, anatomic repair usually leads to satisfactory results, and many authors augment the repair with a capsulodesis technique. In chronic injuries, the presence of static malalignment usually leads to inferior outcomes. Various techniques have been devised and improved over the years. These techniques appear to provide a more anatomic reconstruction, with less loss of motion; motion is 60-80 % of the contralateral side and grip strength averages 65-90 %. Once there is cartilage loss, the surgeon only has salvage procedures to choose from, tailored to the degree of arthritis.

Keywords: Review; Rupture; SL ligament; SLIL ligament; Scaphoid rotatory subluxation; Scapholunate interosseous ligament; Scapholunate ligament; Tear.

Fig. 1

Intraoperative picture of SL repair augmented with DIC capsulodesis. This patient had a subacute SL injury (2 months out from injury) with dynamic instability and poor quality SL ligament. A dorsal approach with ligament-sparing capsulotomy is displayed in the large window. In the close-up view, the scaphoid and lunate are labeled (S and L, respectively). The SLIL is avulsed off of the scaphoid. After reduction of the deformity and fixation with K-wires, the SL ligament was repaired. The proximal one half of the DIC is detached from its radial attachment and attached onto the scaphoid with a suture anchor as described by Pomerance. The scapholunate interval was closed (picture courtesy of David B. Drake)

Fig. 2

The three most common tenodesis techniques. a Brunelli: A 7-cm strip of distally attached FCR tendon is fed through a tunnel in the distal scaphoid from volar to dorsal then fastened to the dorsoulnar edge of the radius. The dorsal pull of the FCR tendon reduces the rotatory subluxation of the scaphoid and the widening of the SL interval. b Van Den Abbeele: The graft is passed under the radiotriquetral ligament, tensioned, and sewn onto itself. c Garcia-Elias: The graft is attached to a trough in the lunate with suture anchors, then passed through the dorsal radiocarpal ligament and secured onto itself. The technique is called the “tri-ligament tenodesis” because it is intended to reconstruct the STT, dorsal SL, and dorsal radiotriquetral ligaments. Reprinted with permission from Howlett et al. [26]

Fig. 3

a Schematic of scaphoid tunnel locations used in this study from a lateral view. Dashed lines indicate the course of the tunnel with a more distal exit point. Solid lines indicate the course of the tunnel with a more proximal exit point. b Schematic of scaphoid tunnel locations used in this study from a postero-anterior view. Tunnels were placed centrally in the scaphoid starting at the volar distal pole and exiting either in the dorsal–distal pole (D) or in the dorsal–proximal pole at the scapholunate interval (P) under fluoroscopic guidance. Adapted with permission from Howlett et al. [26]