Colles fracture is the most common type of distal radial fracture and are seen more commonly in elderly women because the bone is weakened by osteoporosis.
Colles fracture is, however, found in all adult age groups and when it occurs in younger age groups, it usually is due to high impact trauma or fall.
This fracture was first defined by Abraham Colles.
The term Colles fracture is classically used to describe a fracture at the distal end of the radius, at its cortico-cancellous junction.
Mechanism of Colles Fracture
Colles fracture occurs when a person falls on outstretched hand with the forearm in pronation and wrist in dorsiflexion [The position one attempts to break forward fall.
On fall in this position, the proximal row of wrist bones transfers energy to the distal radius, in the dorsal direction and along the long axis of the radius leading to angulation and impaction.
Classical Colles fractures have the following characteristics
- Transverse fracture of the radius
- One inch (2.5 cm) proximal to the radio-carpal joint
- Dorsally displaced and dorsally angulated
Presentation of Colles Fracture
There is a history of fall and the patient presents with a deformity in the wrist. In elderly patients, in whom the fracture is common, the swelling is minimal. However, in young patients, the swelling can be substantial as the injury required to break the bone is more and thus injury to associated soft tissues is also more.
Imaging of Colles Fracture
Plain films are usually sufficient though a CT may be desired in case of intra-articular extension of the fracture.
Ap and lateral wrist x-rays usually suffice. The fracture appears extra-articular, and usually proximal to the radioulnar joint.
Dorsal angulation of the distal fracture fragment is present to a variable degree. There is also usually impaction with resultant shortening of the radius.
Colles fracture have following deformities
- Dorsal angulation
- Radial shortening [impaction]
- Loss of radial inclination
- Ulnar angulation of the wrist
- Dorsal displacement of the distal fragment
- Comminution at the fracture site
- Associated fracture of the ulnar styloid may be present in 50% of the cases.
Treatment of Colles Fracture
Most of the Colles’ fractures are treated by closed reduction and cast immobilization. The cast extends from below the elbow to the metacarpal heads and holds the wrist somewhat flexed and in ulnar deviation. The cast is called Colle’s cast.
Open reduction and internal fixation should be considered in the case of
- Unstable fracture
- Failure of closed reduction
Complications of Colles Fracture
Colles fracture almost always unite. An unreduced or insufficiently reduced fracture would go into malunion and result in dinner fork deformity. These patients also may develop tear of extensor pollicis longus due to increased friction.
Reflex Sympathetic Dystrophy
It is also known as complex regional pain syndrome and is characterized by severe pain, swelling and changes in the skin in the involved region. Nerve involvement may or may not be present.
Carpal Tunnel Syndrome
This occurs due to constriction of space around the medial nerve in the wrist following trauma.