Trauma X-ray - Upper limb
Hand/fingers
The hand comprises the metacarpal and phalangeal bones. Fractures and dislocations are usually straightforward to identify, so long as the potentially injured bone is fully visible in 2 planes.
Finger joints commonly dislocate and are susceptible to avulsion injuries.
Standard views are posterior-anterior (PA), oblique and lateral.
Key points
- Finger injuries visible on X-ray include bone fractures, dislocations and avulsions
Hover over image to show findings
Bones of the hand - Normal (PA) X-ray
- Finger bones articulate at the metacarpophalangeal joints (MCPJ), the proximal interphalangeal joints (PIPJ) and the distal interphalangeal joints (DIPJ)
- The fingers each have 3 phalanges - proximal - middle and distal
- The thumb has only 2 phalanges - proximal and distal - joined by the interphalangeal joint (IPJ)
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Finger dislocation
Finger dislocation is usually evident clinically. X-ray can be used to check for underlying bone injury and to reassess following reduction of the dislocation.
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Finger dislocation
- The proximal phalanges are dislocated at the 4th and 5th MCPJs
Finger shaft injuries
Some finger fractures are easy to identify, but others are more difficult to spot because of overlying bones or soft tissues.
The most common metacarpal fracture is the 'boxer's' type injury.
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Boxer's fracture - 2 examples
- The transverse fracture on the left is easy to see
- The fracture on the right is more subtle - close observation shows an oblique fracture
- Both examples show soft tissue swelling - often a useful sign of a finger fracture
Intra-articular fractures
Intra-articular fractures have a worse prognosis and are often the most difficult to see. Check all views available. If a fracture is not visible and there is sufficient clinical suspicion of bone injury then a request for further views may be helpful.
Intra-articular fracture example - Bennett's fracture
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Bennett's type fracture
- The thumb metacarpal base intra-articular fracture is much more easily seen on the oblique image
- This injury is termed a 'Bennett's' type injury - as in this case there is invariably a degree of subluxation/dislocation of the metacarpal base
Mallet finger injury
Hyperflexion of the DIP joints may result in avulsion of the distal phalanx base on the dorsal side. More commonly there is tearing of the extensor tendon which is an injury not directly visible with X-ray.
If there is a clinically evident mallet deformity, but no bone injury, do not make the mistake of thinking there is no significant injury.