Laboratory Studies
Choose appropriate studies base on patient comorbidities as determined by the history and physical examination.
Imaging Studies
Radiographs
The primary means of evaluating hand injuries beyond the history and physical examination is through plain radiographs.
Significant injury to the hand should be assessed first with posteroanterior (PA), lateral, and oblique views.
The Roberts view is helpful in more fully assessing the first metacarpal base. See the image below.
The Brewerton view is helpful in detailing the anatomy of fractures and chips of the metacarpal heads. See the image below.
The clenched fist view can reveal ligamentous injuries at the metacarpal bases and intercarpally.
Radiographic strategies for other injuries include the following:
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CMC injury
Fractures in this area of the hand are hard to diagnose as the radiographic evidence is often subtle, and additional rotated views may be necessary. The key to radiographic diagnosis lies in the subtle loss of joint space, as seen on AP projections. This often appears as a "broken saw tooth" sign at the CMC joint. This sign may be accompanied by displacement noted on the lateral or oblique views. Tomograms may be necessary to accurately diagnose these injuries.
It is important to look closely for multiple injuries; the interosseous ligaments are strong, and a fracture-dislocation of one metacarpal is often accompanied by that of one or more of its neighbors. Displacement in dislocation is usually dorsal, as the dorsal ligaments are weaker.
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Metacarpal shaft and neck injury: Usually, a diagnosis can be made by observing edema, ecchymoses, pain, and deformity at the fracture site, although swelling can mask the deformity. AP, lateral, and oblique radiographs typically will demonstrate the fracture and displacement.
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Metacarpal head fractures: Evaluation of these injuries may require additional imaging studies, such as Brewerton view radiography, tomography, or CT scanning, to evaluate for fracture and displacement.
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MCP dislocation: MCP dislocations are readily apparent on physical examination. AP radiographs show overlap of the metacarpal head and base of the proximal phalanx. The lateral radiograph is diagnostic with the presence of dorsal displacement of the proximal phalanx.
CT scanning
Plain tomography or CT scanning can be helpful in diagnosing intra-articular injuries to determine fracture alignment and displacement.
These studies may be indicated to evaluate carpometacarpal fracture-dislocations or metacarpal head injuries.
Diagnostic Procedures
Traction radiographs
Radiographs taken in the PA and lateral dimensions while applying traction to the injured digit(s) can be helpful in evaluating injuries when there is significant comminution of the fracture. This is especially true with intra-articular injuries.
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Displaced fourth and fifth metacarpal fractures, anteroposterior view.
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Displaced fourth and fifth metacarpal fractures, lateral view.
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Fourth and fifth metacarpal fractures, oblique view.
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Fourth and fifth metacarpal fractures after intramedullary pinning, anteroposterior view.
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Fourth and fifth metacarpals after intramedullary pinning, lateral view.
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Complex second metacarpophalangeal dislocation in a skeletally immature patient. Note the position of the finger and dimpling of skin on volar hand.
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Radiograph of the hand of the patient in Image 6.
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Intraoperative photo of the second metacarpophalangeal joint of the patient in Images 6 and 7. Note the displaced volar plate between the metacarpal head and the proximal phalanx.
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Metacarpophalangeal ligaments.
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Metacarpophalangeal musculoskeletal structure.
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Brewerton view.
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Roberts view.