Author: Josh Bickley / Editor: Liz Herrieven / Codes: SLO1, SLO4, TP7 / Published: 09/04/2019

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Our hands are important. The sensory information they collect and their ability to co-ordinate complex movements allow us to explore and physically interact with our environment. This also makes them vulnerable to injury and even seemingly trivial trauma can have severe social consequences for people if important function is lost.

Minor injuries, including those of the hand and wrist, are often investigated and treated by specialist nurses so some ED trainees are not confident in their management. This is a general summary of fractures and dislocations at or below the distal radius/ulna.

When it comes to fractures and dislocations it is important to remember general principles for any orthopaedic injury. An assessment of the neurovascular status of the limb distal to the fracture should be made and if any compromise detected then the injury needs urgent reduction. Open fractures all require antibiotic cover and it’s important to check tetanus status.

Radius and Ulna

Colles’ fractures are an ED staple – so much, we’ve got an entire blog post on them. Common in elderly patients, they are evidence of osteoporotic disease and generally occur as a result of low energy trauma – most often a FOOSH (fall onto outstretched hand). As the distal radius fractures it is displaced and angulated dorsally. It may have an associated ulna styloid fracture. Most (but not all) EDs will reduce these fractures in the emergency department (providing there are no complicating factors) and if successful will refer the patient in a plaster of Paris (POP) backslab for a fracture clinic appointment. Patients having a Colles’ reduction will need either a method of sedation or local anaesthetic block to allow the reduction to be performed. This varies between different clinicians and departments. Reduction requires three operators, one to provide counter traction, one to reduce the fracture and one to apply the plaster. With counter traction in force, with a flexed elbow and the wrist in pronation, the distal bone fragment should be pulled distally away from the overlapping proximal fragment and the wrist should then be flexed to move the fragment in a volar direction in line with the proximal bone. If this is difficult it may help to hyperextend at the fracture to exaggerate the deformity prior to reduction. Once reduced it is important to keep traction and counter traction while the POP is being applied.


Picture from Wikipedia

A Smith’s fracture is often described as a “reverse Colles'”. The distal radius is displaced in a volar direction and the mechanism of injury is a fall onto the dorsal aspect of the wrist. In contrast to Colles’ fractures these are a rare injury. The manipulation of the fracture is similar to that of a Colles’ fracture but all the directions are reversed. The rate of re-displacement is very high in Smith’s fractures and they should generally be left for the orthopaedic team to either manipulate or (more commonly) fix surgically (providing there is not urgent neurovascular compromise). Most departments that I have worked in want ED to try once, as it will be more comfortable in a POP if it has been reduced.


Picture from radiopaedia.org

A Barton fracture is a fracture of an intra-articular fragment of the distal radius with an associated dislocation of the radiocarpal joint so that the hand and carpal bones are displaced along with the fracture segment. The fracture may be volar or dorsal, volar being more common. These fractures are inherently unstable and should be referred to orthopaedics as most will need ORIF (open reduction and internal fixation).


Image from wikipedia.org

Carpal Bones
Scaphoid fractures are not visible on initial imaging in about 16% of cases but, as a missed scaphoid carries a risk of avascular necrosis with significant morbidity, they are often treated clinically. Seventy to eighty per cent of the blood supply of the scaphoid is from the dorsal branch of the radial artery that flows from a distal to proximal point in the bone. This retrograde blood flow makes the scaphoid vulnerable to avascular necrosis and non-union if a fracture, especially at the proximal pole, is missed and not treated. Tenderness in the anatomical snuffbox, scaphoid tuberosity (with pressure applied to the wrist crease with the wrist in dorsiflexion) or a positive scaphoid compression test (axial loading along the thumb metacarpal) should raise your suspicion of a scaphoid fracture. Remind yourself of the anatomy here. For simple, undisplaced fractures or if the X-ray appears normal the traditional treatment is a POP backslab with thumb extension, however, many centres have now moved to splints rather than backslabs, especially if the x-ray looks completely normal. Patients should have follow up arranged, either in ED or fracture clinic, depending on local policy. If there is no clear fracture the patient should be re-examined and re-imaged in 10-14 days. Imaging modality and follow-up process varies between centres. MRI has the greatest sensitivity followed by CT and then plain x-ray but the reverse is generally true when it comes to availability. Displaced fractures should be referred to orthopaedics acutely.


Image from flickr.com

Scapholunate joint dislocation can be due to acute injury or degenerative disease. If due to injury it presents in a similar way to scaphoid fracture with widening of the scapholunate joint, or Terry Thomas sign on the x-ray. For the youngsters, Terry Thomas was a comic actor in the 1950s with a marked gap between his front teeth. These injuries can have a splint applied and will often heal with conservative management but follow up with a hand specialist is required.

File:ScaphoLuncateDisoMark.png

Image from wikimedia.org

Lunate and perilunate dislocations are often described together as they are important diagnoses not to miss and are often only diagnosed on a lateral wrist film. When looking at a lateral wrist x-ray the appearance is often described as an apple (capitate) sitting in a teacup (lunate) sitting on a saucer (distal radius) with the metacarpal head on top of the capitate. An imaginary line should transect the centre of all these structures in a normal patient. In a lunate dislocation, often after a FOOSH, patients present with volar wrist pain and swelling. The lateral x-ray shows the lunate move in a volar direction in relation to the above structures, the so called ‘spilled teacup sign’. On the AP view the lunate appears triangular. Lunate dislocations carry a high risk for median nerve injury and chronic pain. They should be referred for surgical manipulation.


Image from: wikimedia.org

Perilunate dislocations and generally more painful and are associated with much greater levels of swelling. The whole carpus dislocates posteriorly in relation to the lunate. They are usually a high impact injury and associated scaphoid fractures are common. On x-ray the capitate and the metacarpal bone above move dorsally in relation to the lunate bone (the apple is behind the teacup). Median nerve damage is common and urgent reduction by a hand specialist is required. CT scans are often required acutely to determine the damage to associated carpal bones.

Image from wikimedia.org

Triquetral fractures are commonly missed and should be suspected when there is dorsal tenderness of the wrist. Care should be taken to inspect the posterior surface of the carpal bones on the lateral film. Most can be discharged in a POP and referred to a hand specialist clinic as an outpatient but some will later need an ORIF.

Image from wikimedia.org

Other fractures of the carpal bones are difficult to diagnose and if there is a strong suspicion of a fracture they should be discussed or referred on for further imaging and evaluation.

A confusing part of hand fracture referral is that there is variation (and sometimes crossover) between which specialty provides the definitive treatment in different departments. If your department has on site plastic surgery it is more than likely that all hand injuries go to them, if not then hand injuries may go the orthopaedics or some may need to be referred to an offsite plastics service. Each department will hopefully have a policy of what injuries each specialty will take.

Metacarpals and Phalanges
Non-thumb metacarpal fractures generally do well with conservative management. Non-displaced neck and head fractures may usually be “buddy” strapped to the neighbouring digit. Displaced fractures require a volar backslab and in many centres fractures of the base and shaft are also treated with POP. Generally all metacarpal fractures get followed up routinely in a specialist clinic but some hospitals will have a specific policy on which need follow up and which can be followed up by the GP if required. Dislocations of the base of metacarpal bones require reduction by a specialist. Thumb metacarpal fractures cannot be buddy strapped and need splinting and specialist follow up. A Bennett’s fracture (or fracture dislocation) is a fracture through the base of the thumb metacarpal bone caused either by a fall onto the thumb or by delivering a punch with the hand wrapped around the thumb. These tend to displace laterally and need discussion with a hand specialist to consider operative management.

File:Bennetts Fracture.jpg

Image from wikimedia.org

Undisplaced, non articular fractures of the phalanges do not need specialist follow up and can be treated by strapping the affected digit to a neighbouring finger. Distal phalanx fractures have a tendency for the distal fragment to displace in a volar direction due to the FDP tendon and so are better treated with a mallet splint.

File:MalletFinger.PNG

Image from wikimedia.org

Displaced fractures, open fractures and those involving the joints (including volar plate avulsion fractures) need reducing and should be followed up by a hand specialist. If there is a digital amputation the wound should be dressed in a non-adherent dressing and the amputated digit should be wrapped in saline swabs and placed in a mix of ice and water. Both parts should be x-rayed and urgent discussion should be had with a hand surgeon. IV antibiotics should be given as with all open fractures.

Image from wikimedia.org

Dislocations of the MCP, PIP and DIP joints can usually be reduced in the emergency department. Dorsal dislocations are far more common than volar dislocations. The longer a dislocation is left the harder it is to reduce. Analgesia options include Entonox, light sedation, local anaesthetic block, simple analgesia or, if it is a relatively recent dislocation in a relaxed patient, it may be done without any. To reduce apply traction distally and ease the dislocated back into joint by applying pressure to the base. MTP dislocations need buddy strapping and IP joints are best treated with a mallet splint. An x-ray should be obtained post reduction to ensure good alignment and that there is no associated fracture. Simple dislocations do not require specialist follow up if there is no further instability.

Further Reading
RCEM Colles Blog