Subtle radiographic signs of hamate body fracture: a diagnosis not to miss in the emergency department

Abstract

Hamate fractures are estimated to represent 1.7% of all carpal fractures and can occur at the hamulus (hook) or hamate body depending on mechanism of injury. Fractures of the hamate body can be exceedingly difficult to identify on standard wrist and hand radiographs in the emergency department. If the diagnosis is missed in the emergency department, orthopedic referral is often delayed. This can result in lasting functional disability for the patient, as these fractures have a propensity to destabilize the fourth and fifth carpometacarpal (CMC) joints. In this pictorial essay, we present six radiographic signs indicative of hamate body fracture with computed tomography (CT) imaging correlation. Injury mechanism and fracture classification schemes are portrayed to aid in the understanding of these injuries. Once radiographs raise suspicion for a hamate body fracture, further characterization with CT and orthopedic referral is paramount. Goals of orthopedic management include reestablishment of the fourth and fifth CMC articular surface, stabilization of the CMC joints, and appropriate treatment of concomitant soft tissue injury.

Carpometacarpal 4/5 Fracture Dislocations: Fracture Morphology and Surgical Treatment

“…1,2,[4][5][6] A high clinical suspicion and adequate use of radiological tests are required for diagnosing the injury. 1,7 An early diagnosis is essential to avoid or minimize the risk for fracture malunion, nonunion, posttraumatic arthritis, and chronic pain. 3,7 Plain radiography is not optimal to evaluate this area of the carpal anatomy, due to the irregular topography, small fracture fragments, and complex articulations.…”

Functional Outcome following Headless Compression Screw Fixation for Hamate Fractures

“…Hamate fractures are rare injuries and account for 2% of carpal bone fractures. 1,2 Despite being rare in the general population, hamate fractures are frequently diagnosed in athletes, such as baseball players, tennis players, and golfers. 3 Fractures of the hook of the hamate (hamulus) usually occur due to direct trauma, such as a fall on the hand or direct pressure by sports equipment as a golf club.…”

“…1 Injuries associated with fractures of the corpus of the hamate bone are fracture dislocations of the fourth and fifth carpometacarpal (CMC) joints and fractures of the basis of the fourth and fifth metacarpal bases. 2,5,6 Hamate fractures can be classified according to Milch's classification which distinguishes fractures of the hook of the hamate (type 1) and corpus (types 2a and 2b). Type-1 fractures can be divided into three types as follows: (1) fractures of the tip of the hook of the hamate (type 1), (2) fractures of the middle part of the hook of the hamate (type 2), (3) and fractures at the base of the hook of the hamate (type 3).…”

“…2,5,6 Hamate fractures can be classified according to Milch's classification which distinguishes fractures of the hook of the hamate (type 1) and corpus (types 2a and 2b). Type-1 fractures can be divided into three types as follows: (1) fractures of the tip of the hook of the hamate (type 1), (2) fractures of the middle part of the hook of the hamate (type 2), (3) and fractures at the base of the hook of the hamate (type 3). Corpus fractures can be divided into types 2a and 2b which are coronal and transverse fractures of the corpus, respectively.…”

“…Complications of inadequately treated fractures include symptomatic nonunion, avascular necrosis (AVN), and CMC posttraumatic arthritis. 1,2 Four types of AVN are distinguished as total, proximal pole, distal pole, and hamate hook. Blood supply to the hamate bone originates via three nonarticular surfaces which are dorsal, volar, and medial on the base of the hamate hook.…”