Các loại gãy xa xương quay đặc biệt (Radius, Distal Fractures) Colles fracture In 1813, Abraham Colles described the Colles fracture, which is reported to be the most common distal radial fracture. The injury is usually produced by a fall onto an outstretched hand (FOOSH) mechanism with the wrist in dorsiflexion. The impact produces a transverse fracture in the distal 2-3 cm of the radial articular surface. The fracture is dorsally displaced and may be comminuted. The fracture pattern is often described as a silver or dinner-fork deformity. The fracture fragments are usually impacted and comminuted along the dorsal aspect; the fracture can extend into the epiphysis to involve the distal radiocarpal joint or the distal radioulnar joint. Resnick noted that 50-60% of Colles fracture cases are associated with an ulnar styloid fracture.An associated ulnar styloid fracture should prompt an investigation for tears of the TFC. The TFC extends from the rim of the sigmoid notch of the radius to the ulnar styloid and is thought to stabilize the distal radioulnar joint AO Classification of Colles Fractures A Extra-articular B Partial articular C Complete articular 1 Simple articular and metaphyseal fracture 2 Simple articular with complex metaphyseal fracture 3 Complex articular and metaphyseal fracture Smith fracture Robert Smith described the Smith fracture in 1847. An impact to the dorsum of the hand or a hyperflexion or hypersupination injury is thought to be the cause. A Smith fracture is usually called a reverse Colles fracture because the distal fragment is displaced volarly. It is often described as a garden-spade deformity. The ulnar head can be displaced dorsally Thomas Classification of Smith Fractures I Most stable, extra-articular, transverse distal radial fracture with palmar and proximal displacement II Barton type, palmar-lip fracture of the distal radius with dislocation of the carpus III Unstable, oblique, juxta-articular fracture of the distal radius and tilted palmar Barton fracture John Rhea Barton characterized the Barton fracture in 1838.This fracture involves a dorsal rim injury of the distal portion of the radius. The volar Barton fracture is thought to occur with the same mechanism as the Smith fracture, with more force and loading on the wrist. The dorsal Barton fracture is caused by a fall on an extended and pronated wrist, increasing carpal compression force on the dorsal rim. The salient feature is a subluxation of the wrist in this die-punch injury. The Barton fracture involves either the palmar or dorsal radial rim, and the mechanism is intra-articular. By definition, this fracture has some degree of carpal displacement, which distinguishes it from a Colles or Smith fracture. The palmar variety is more common than the dorsal type Hutchinson, chauffeur's, or radial styloid fracture The chauffeur's fracture derives its name from injuries that were acquired, in the days when motor vehicles were cranked, when a vehicle backfired. The force is described as a direct axial compression of the scaphoid into the radial facet. The radial styloid is fractured, with associated avulsion of the radial collateral ligament. A chauffeur's fracture represents an avulsion related to the attachment sites of the radiocarpal ligaments or of the radial collateral ligament. Scapholunate dissociation and lesser arc injuries of the wrist may be indicated by a fracture line on the radial articular surface between the scaphoid and lunate fossae. The PA view usually demonstrates the lesion. Wood and Berquist report that little or no abnormality is seen on lateral views. Chauffeur's fractures are classified as simple or comminuted radial styloid fractures and as displaced or nondisplaced fractures. These injuries show no evidence of carpal subluxation. Complications include scapholunate dislocation, osteoarthritis, and ligamentous damage. Galeazzi, or Piedmont, fracture A Galeazzi fracture results from a FOOSH mechanism with the forearm hyperpronated or from a direct impact to the dorsal radial wrist. The radial diaphysis at the distal and middle third junction is fractured, with associated subluxation of the distal radioulnar joint. On PA views, the radius is shortened and the radioulnar joint is disrupted. Radioulnar distances greater than 2 mm are suggestive of a ligamentous injury and/or a tear of the TFC. On the lateral view, the distal radius is angulated either volarly or radially as a result of the pull of the brachioradialis muscle with more than 3 mm of ulnar displacement. An associated ulnar styloid fracture also may be present. PA views may show a displaced radial and ulnar styloid. The lateral view may reveal the associated radioulnar dislocation that is occult on the AP view. Classification is based on the direction of displacement of the distal fracture fragment. Complications include radial malunion, nonunion, and persistent subluxation of the radioulnar joint Essex-Lopresti fracture The Essex-Lopresti fracture consists of a comminuted and displaced radial head fracture along with disruption of the distal radioulnar joint and interosseous membrane. The thickened ridge of the scaphoid and lunate facets dissipates the energy delivered to the wrist in a FOOSH injury and is thought to account for fractures that occur between the scaphoid and lunate facets of the radius. The fracture line originates at the junction of the scaphoid and lunate fossae on the radial articular surface and courses laterally in a transverse or oblique direction. The intra-articular distal radial fracture of the radial styloid is associated with an avulsion of the radial collateral ligament. Routine PA and true lateral views are obtained. On the PA view, overlap, widening, or incongruity of the radioulnar joint should be noted. Resnick notes that careful radiographic positioning and measurements are essential, as is transaxial CT scanning or MRI, to assess the extent of displacement or subluxation of the radioulnar joint.9 Complications are similar to those of a Colles fractures and include radioulnar joint instability and TFC damage. Pediatric distal radial fracture The distal one third of the forearm is the most common fracture site in children. Dicke notes that these make up 35.8-45% of all pediatric fractures. The primary mechanism of injury is a FOOSH mechanism. Unlike such falls in adults, these falls rarely lead to intra-articular fractures in children, but fractures can occur at the diaphyseal-metaphyseal junction or at the physis. Boys have a higher frequency of distal radial fractures than do girls. Five classifications of pediatric fractures are used, as follows : * Plastic deformation - This occurs most commonly in the ulna and fibula. * Buckle (torus) fracture - In this, the diaphysis (cortical bone) causes the metaphysis to buckle under compressive forces. * Greenstick fracture - This fracture occurs when the tension side of the bone fails as it is bent. * Complete fracture - A complete fracture propagates through the entire bone and can occur as a spiral fracture, an oblique fracture, or a transverse fracture. * Epiphyseal fracture - This fracture involves the growth plate and/or physis. The distal radial physis is the most frequently injured physis. Fractures involving the physis are categorized as follows, using the Salter-Harris (SH) classification: * Type I - A fracture through only the physis * Type II - A fracture occurring through the physis and obliquely through the metaphysis * Type III - A fracture occurring through a portion of the physis and longitudinally through the epiphysis * Type IV - An oblique fracture extending through the metaphysis, physis, and epiphysis . Các loại gãy xa xương quay đặc biệt (Radius, Distal Fractures) Colles fracture In 1813, Abraham Colles described the Colles fracture, which is reported to be the most common distal. the dorsal radial wrist. The radial diaphysis at the distal and middle third junction is fractured, with associated subluxation of the distal radioulnar joint. On PA views, the radius is shortened. subluxation of the radioulnar joint.9 Complications are similar to those of a Colles fractures and include radioulnar joint instability and TFC damage. Pediatric distal radial fracture The distal