Introduction to Trauma X-ray Fracture complications
Key points
Fractures are often complicated by soft tissue injury which may need to be treated prior to obtaining X-rays
Soft tissue injuries are usually better appreciated on clinical examination than on X-rays
Complications may also relate to treatment of fractures
Soft tissue injury complications
Many bone fractures are complicated by a significant soft tissue injury that the X-ray may or may not show. Soft tissue injuries may be threatening to life or limb, and for this reason thorough clinical examination is required BEFORE obtaining the X-ray. For example, it is essential to check for neurological and vascular compromise, which may mean immediate fracture reduction is appropriate prior to imaging.
An 'open fracture' is any fracture complicated by breach in the adjacent skin. This is evident clinically and often difficult to appreciate on X-rays.
A 'closed fracture' (no break in skin) that is clinically complicated by soft tissue injury is correctly termed a 'complex fracture'.
The soft tissue injuries associated with complex and open fractures are usually more evident clinically than on X-ray.
Highly comminuted fracture of the index finger middle phalanx
'Open' fracture of the index finger - severe soft tissue injury with breach in the skin (obvious clinically)
The fracture of the middle finger middle phalanx is 'closed' (no breach in the skin clinically)
Bone injury complications
X-rays are commonly used to diagnose fracture complications visible in the bones themselves, or complications arising from treatment.
Success of bone healing is affected by the location and type of injury, and is influenced by factors such as underlying bone disease and systemic illness.
'Malunion' is a complication that arises if a fracture is allowed to heal in an abnormal position. Failure of bone healing following a fracture is termed 'non-union'.
The roll over image is an 'ulnar deviation view' of the scaphoid - note the ulna has not moved and the carpal bones are stressed towards the ulnar side
The ununited fracture (arrowheads) visible on the Posterior-Anterior (PA) view is markedly widened on the ulnar deviation view
There is no bone union at the fracture site and the distal part of the scaphoid is unstable
Avascular necrosis (AVN)
Occasionally a bone will not heal because its internal blood supply is compromised. This may result in AVN - the death of bone cells through lack of blood supply.
Blood supply of the scaphoid is from distal to proximal
Injury to the blood supply may result in AVN
Bone sclerosis of the proximal pole can be a sign of AVN
Osteopenia and Sudeck's atrophy
Normal bone formation is influenced by mechanical stress. Occasionally fractures requiring prolonged immobilisation will result in osteopenia due to disuse.
Reduced bone density may also result from Sudeck's atrophy, also known as 'reflex sympathetic dystrophy' or 'complex regional pain syndrome'. This is a painful syndrome which is poorly understood, but thought to be caused by dysfunction of the autonomic nervous system and regulation of blood supply.