Treatment of scapholunate ligament injury: Current concepts

Abstract

Injuries to the scapholunate joint are the most common cause of carpal instability.An isolated injury to the scapholunate ligament may progress to abnormal joint mechanics and degenerative cartilage changes.Treatment for scapholunate instability is aimed at arresting the degenerative process by restoring ligament continuity and normalising carpal kinematics.Early arthroscopic diagnosis of scapholunate injury is mandatory for establishing the prognosis of the injury, as a proper ligament repair is recommended within four to six weeks after trauma.In this review, anatomy, diagnosis and treatment of scapholunate ligament injury and carpal instability are discussed. Recommendations for treatment based on the stage and classification of injury and the degree of instability and arthritic changes are proposed. Cite this article: EFORT Open Rev 2017;2:382-393. DOI: 10.1302/2058-5241.2.170016.

Keywords: carpal instability; scapholunate ligament; wrist; wrist arthroscopy.

Fig. 1

The scapholunate ligament is C-shaped. Its dorsal (D) component is the strongest (P, proximal; V, volar).

Fig. 2

Chauffeur’s fracture with concomitant scapholunate dissociation.

Fig. 3

Dorsal intercalated segment instability (DISI) with a scapholunate angle of approximately 90° (S, scaphoid; L, lunate (red)).

Fig. 4

Scapholunate (SL) advanced collapse after an SL injury, with subsequent arthritic changes at the radiocarpal and mid-carpal joints (SL advanced collapse - SLAC III). Also note the volarflexed scaphoid, appearing triangular distally with the so-called ‘ring sign’.

Fig. 5

Watson’s test – ‘scaphoid shift’ manoeuvre.

Fig. 6

a) Wrist arthroscopy technique. The 2 mm to 3 mm probe inserted through the 6R portal testing the scapholunate (SL) ligament (SLL) in a right wrist. b) Arthroscopic diagnosis of a total SL injury in a left wrist, a so-called Andersson-Garcia-Elias type 1a - ligament avulsion off the scaphoid, according to our new proposed classification (see Discussion and Fig. 9). This total SLL injury and instability with a ‘drive-through phenomena’ corresponds to Geissler grade IV injury (Table 1).

Fig. 7

The three-ligament tenodesis. A schematic drawing (S, scaphoid; L, lunate; RTq, dorsal radiotriquetral ligament; FCR, flexor carpi radialis).

Fig. 8

Plain radiographs (anteroposterior view - right wrist) of proximal row carpectomy (a) and four-corner fusion (b).

Fig. 9

Classification of the dorsal scapholunate (SL) ligament injury, according to Andersson-Garcia-Elias. Type 1: lateral avulsion (42% of all SL injuries); type 2: medial avulsion (16%); type 3: mid-substance rupture (20%); type 4: partial rupture plus elongation (22%).