Colles fracture

Summary

Dorsally angulated, distal radius fractures (Colles fractures) are a relatively common presentation to the emergency department (ED). They are mostly caused by a fall onto an outstretched hand.

ED assessment should include pain, neurovascular and radiographic assessment. The majority of fractures can be managed in a short arm backslab and referred to an orthopaedic fracture clinic. However, significantly displaced or open fractures should be referred to an orthopaedic doctor straight away, and closed reduction in the ED may be indicated.

Classification

Although several classification models exist (Frykmanns, AO, etc), it is often easier and more useful to classify the fracture using the following descriptors:

• Open vs closed
• Intra-articular vs extra-articular
• Simple vs comminuted
• Fracture line orientation
• Degree of angulation
• Degree of impaction
• Degree of displacement
• Other concomitant fracture, e.g. ulna styloid

Epidemiology

Distal radius (Colles) fractures account for almost 17% of all fractures that occur in adults. They occur most often in the following two groups:

• Elderly individuals with osteoporotic bone who sustain these fractures from low-energy trauma.
• Young adults following high-energy trauma.

Distal radius fractures occur:

• most often in older postmenopausal women
• 4 times as often in females than in males
• most often between the ages of 60–69 years.

Presentation

The most common cause of distal radius (Colles) fractures is from a fall onto an outstretched hand with wrist in extension. The classic appearance is dorsoradial swelling or dinner fork deformity of the wrist. In addition to pain, the patient may also experience paraesthesia secondary to nerve compression.

Imaging

Plain radiographs should be ordered if suspicious of fracture. The series should include AP, true lateral and oblique views. The AP view allows measurement of radial height, radial inclination and ulnar variance while the lateral view allows measurement of volar tilt.

Definitions, normal values and acceptable criteria are as follows:

• Radial height: the distance between two parallel lines drawn perpendicular to the long axis of the radial shaft – one from the tip of the radial styloid and the other from the ulnar corner of the lunate fossa. Normal value = 12mm (acceptable loss of height with fracture is 3mm in young and 5mm in elderly populations).
• Radial tilt or inclination: the angle between two lines – one drawn perpendicular to the long axis of the radius at the ulnar corner of the lunate fossa and the other between that point in the lunate fossa and the tip of the radial styloid. Normal value = 23°.

CT may be indicated to evaluate intra-articular involvement and for preoperative planning.

MRI is not usually indicated in the acute context but may be useful in the medium-term to evaluate soft tissue structures of the wrist.

Management options

Neurovascular assessment should be performed and include:

• radial pulse
• capillary return to finger tips
• radial, median and ulnar nerve power/sensation in the hand.

Referral and follow-up requirements

Stable Colles fractures can be followed up in a fracture clinic or equivalent approximately 1 week post injury. This will allow time for the initial swelling to subside so that a full circumferential cast can be applied.

Potential complications

Complications can manifest acutely or in the medium- to long-term.

The most common acute complication is median nerve neuropathy associated with carpal tunnel compression. The incidence can be reduced by elevating the limb, moving the fingers and avoiding immobilisation in excessive wrist flexion.

Common medium-term complications include:

• rupture of the extensor pollicus longus tendon (caused by mechanical attrition of the tendon)
• skin irritation, blisters or pressure areas (secondary to ill-fitting plaster cast)
• development of complex regional pain syndrome.

Common long-term complications include fracture malunion and osteoarthritis of the wrist.

Patient advice

Discharge advice should include information relating to:

• monitoring for compartment and/or compression syndromes, e.g. increasing pain/analgesia use
• appropriate analgesia dosage and frequency
• finger and elbow range of motion exercises
• contraindicated activity, i.e. lifting heavy objects
• care of temporary casts fact sheet.

Resources

• Altissimi M, Mancini GB, Azzarà A, et al. Early and late displacement of fractures of the distal radius. The prediction of instability. Int Orthop. 1994;18(2):61-65. DOI:10.1007/BF02484412
• Ahn L, Vitale M, Franko O. Distal radius fractures
  Source: Orthobullets
• Distal radius fractures in adults
  Source: UpToDate (NSW Health login required)