Perilunate fractures and dislocations are surgical emergencies with potentially major functional repercussions on the wrist. These lesions have been well classified and updated by Herzberg [1]. Different lesion "pathomechanisms" are based on the pathophysiology initially described by Mayfield in 1980 [2]. Isolated ejection of the scaphoid proximal pole (SPP), on the other hand, has been described in only a few case reports [3], [4], [5], [6] and does not correspond to the situations in the Herzberg or Mayfield classifications. Bone ejection incurs a risk of avascular necrosis despite good osteosynthesis, notably because of precarious vascularization [7]. Reduction by external maneuvers or arthroscopy is often impossible in these cases, which require open surgery, further compromising vascularization.

We detail our management of a 53-year-old patient with isolated SPP ejection, and discuss management.

Case report

A 53-year-old man presented following a 9 m fall onto his left hand. On Initial examination there was a palpable bone fragment in the distal part of his forearm, and no neurovascular deficit. Radiographs revealed scapholunate fracture-dislocation with ejection of the SPP, associated with fracture of the lunate fossa of the radius (Fig. 1). The patient was taken to the operating room within two hours after arrival. The proximal part of the scaphoid was extracted deep to the median nerve (Fig. 2). A posterior approach was used. Capsulotomy was performed at the carpus and extended between the 3rd and 4th extensor compartments. The comminuted fracture of the lunate fossa was exposed. The lunotriquetral ligament and scaphoid fossa were intact. After locating the distal pole of the scaphoid, the proximal pole was fixed using two 2.5 mm Autofix cannulated screws (Medartis). Reduction of the lunate fossa was impossible even with manual distraction, and an external fixator was fitted to help reduce the radial articular surface. Complementary pins were added to fix a larger bone fragment (Fig. 3A). The scapholunate interosseous ligament was sutured with PDS 4/0 suture and the capsule was closed with 3/0 PDS suture and reinserted on the radius with a 3/0 mini-Mitek anchor.

At 6 months postoperatively and after removal of the external fixator and pins, the patient presented disabling signs of complex regional pain syndrome (CRPS) (Fig. 3B). Dedicated occupational therapy was initiated.

At 1 year, the patient presented wrist stiffness (10 ° extension, 30 ° flexion, 20 ° supination and 90 ° pronation), mild pain and grip weakness (JAMAR (Level 2) 4.5 kg, vs 25 kg on the contralateral side). MRI was carried out to check the vitality of the SPP, and ruled out avascular necrosis (Fig. 3C). Further radiographs showed good bone healing of the scaphoid (Fig. 3D).