Falls on an outstretched arm are common, and the radius is often the first to fracture. If there is a supinating component to the fall, the distal ulna may also fracture. In the elderly, distal radius fractures are usually extra-articular metaphyseal fractures, whereas in younger patients, they are usually intra-articular with displacement of the joint surface. There are four types of radial fractures, associated with commonly known eponyms: Colles, Smith, Barton, and Hutchinson (chauffeur).
Colles fractures are the most common. There is dorsal displacement of the distal fragment and apex palmer angulation of the distal fracture fragments; on exam, a “dinner fork” deformity is often described. The Smith fracture is of the distal metaphysis with volar displacement and apex dorsal angulation. This usually results from a blow to the dorsum of the wrist or a hyperflexion injury. Exam reveals a reverse dinner fork deformity. Barton fractures occur along the dorsal or palmer rim of the distal radius and may be associated with dislocation of the radiocarpal joint. Hutchinson fractures are often due to direct impact to the radial styloid with subsequent avulsion.
Several fracture patterns are specific to pediatrics and include the Torus fracture and the Greenstick fracture. Torus fractures (also known as buckle fractures) occur due to compression of the bone, which results in a buckling of the periosteum without a complete fracture line. Radiographic findings can be difficult to identify and may only include a subtle asymmetry when compared to the unaffected side. Greenstick fractures involve disruption of the cortex on only one side of the periosteum.
Colles Fracture. The classic dinner-fork deformity is demonstrated. The distal forearm is displaced dorsally. (Photo contributor: Kristin L. Stevens, MD.)
Management and Disposition
Evaluation requires AP, lateral, and oblique views. Orthopedic consultation is required for comminuted, displaced, unstable, or open fractures, as well as those with greater than 20 degrees of angulation or more than 1 cm of shortening. The patient can be immobilized in a sugar-tong splint. Detailed discharge instructions should be given regarding symptoms of median nerve impingement, including paresthesias and hand weakness, which should prompt return evaluation.
Colles Fracture. Dorsal displacement of the distal fragment. (Photo contributor: Kristin L. Stevens, MD.)
Torus fractures are treated by splinting in position of function with close follow-up; reduction is not required because there is no angulation or displacement. Greenstick fractures require reduction and subsequent casting. Radiographs should be repeated in approximately 1 week to ensure alignment has been maintained.
All fractures of the distal radius must be evaluated for median nerve function before and after reduction.
Colles fractures warrant a high index of suspicion ...