gms | German Medical Science

Objectives/Interrogation: Fractures of the Hamate are rare and difficult to diagnose both clinically and radiographically. It was thought that hook of hamate fractures were sustained by either a fall onto an outstretched hand or by direct impact from a racquet or ball whilst playing sport. We have reviewed our series of hook of hamate fractures from a level 1 trauma centre over a ten year period. This was to assess the aeitology and associated injuries of this uncommon yet significant injury.

Methods: A retrospective analysis of all patients who presented with a hook of hamate fracture to the level 1 trauma centre over a ten year period. The patient demographics and mechanism of injury was collected from the patients notes. All patients underwent radiographs and advanced imaging in the form of either Computed topography (CT) or magnetic resonance imaging (MRI). Imaging was examined for classification and associated injuries.

Results and Conclusions: There were 27 patients who sustained 28 hook of hamate fractures between 2007 to 2017. The fractures occurred through the base of the hamate in 16 patients, the body in 11 patients and the tip in 1. The mechanism of injury in 18 Hamate fractures were sustained whilst falling onto an outstretched hand and of these 6 had an associated carpal fracture. 4 of the 28 fractures were sustained from a direct blow with 2 cases having an associated fracture. 6 of the 28 hamate fractures were sustained from gripping a handle (Tennis racquet, Golf club) with no direct blow or fall reported.

We found no evidence to support the current opinion of hamate fractures being sustained from a direct blow against a handle. The authors feel that the fractures in this patient population occurs as a consequence of the tangential force from the adjacent flexor tendons (flexor digitorium profundus of the ring and little fingers) when maximal grip occurs against the handle. There is also a higher association of scaphoid and carpal fractures (28%) with a hamate fracture than what has been previously been reported in the literature. It is our opinion that with the increasing use of CT or MRI imaging more associated carpal injuries would be identified. This has led to an increased rate of identifying both the hook of hamate fractures and any associated injuries. The authors recommend a thermoplastic splint that has been developed to support the wrist and fingers of the little and ring and prevent excessive FDP movement of these fingers.