Bones of the forearm include the radius and the ulna, with the radius the larger of the two bones of the forearm.
The radius end toward the wrist is called the distal end.
A fracture of the distal radius occurs when the area of the radius near the wrist breaks.
Distal radius fractures are common and the radius is the most commonly broken bone in the arm.
Distal radius fractures usually occurs when a fall causes someone to land on their outstretched hands.
Many distal radius fractures occur in the elderly, and are caused by a fall from a standing position.
Osteoporosis is an associated process in as many as 250,000 wrist fractures/year.
Most common cause of this type of fracture is a fall on an outstretched hand (FOOSH).
Sometimes the distal ulna can also be fractured.
Distal radius fracture is ref2242ed to as a Colles fracture, and almost always occurs about 1 inch from the end of the bone.
A wrist fracture that extends into the joint, it is called an intra-articular fracture.
A wrist fracture that does not extend into the joint is called an extra-articular fracture.
In young adults it is a result of moderate to severe force such as a fall from a significant height or a motor vehicle accident.
In children the fracture may involve the growth plate.
Risk is increased in patients with osteoporosis and other metabolic bone diseases.
Specific types of distal radius fractures are Colles’ fracture; Smith’s fracture; Barton’s fracture and Chauffeur’s fracture.
Presentation is usually present with a history of an injury and localized pain., often with a deformity in the wrist with associated swelling.
If there is compression of the median nerve at the wrist, numbness of the hand may occur.
Digital motion may be inhibited by wrist deformity.
Examination should rule out the presence of any evidence for an open fracture, neurologic impairment or vascular compromise, as well as for more proximal injuries to the forearm, elbow and shoulder.
Injuries to the elbow, humerus and shoulder are common after a fall on out-stretched hand.
Carpal bone fractures such as to the scaphoid may occur, associatd with instability or dislocations of the wrist.
Swelling and displacement can cause compression of the median nerve and an acute carpal tunnel syndrome.
Diagnosis may be evident clinically.
When the distal radius is deformed the fracture should be confirmed by x-rays.
X-rays, CT scan, or MRI can confirm the diagnosis.
CT scan provides informtion about the articular anatomy of the fracture, especially if surgery is considered: it assesses the angle of the joint surface, the loss of length of the radius from the collapse of the fracture, and the distal radioulnar joint.
The most important factor concerning prognosis and treatment is the displacement of the articular joint surface, as it must be smooth for proper function.
Irregularity of the articular surface may cause subsequent arthritis, pain, and stiffness of the wrist.
Articular incongruity is especially common in young individuals with high energy injuries.
Severe articular incongruity cannot be surgically reconstructed, fusion is an option.
Treatment is usually with immobilization, although surgery is sometimes needed for complex fractures.
Distal radius fractures commonly result in loss of length as the radius collapses from the injury.
The Universal classification system:
Type I: extra articular, undisplaced
Type II: extra articular, displaced
Type III intra articular, undisplaced
Type IV: intra articular, displaced
Anatomic description of the fracture includes:
Articular incongruity
Radial shortening
Radial angulation
Comminution
Open or closed injury
Associated ulnar styloid fracture
Associated soft tissue injuries
Almost all fractures heal, with nonunion of a radius fracture being rare.
If a deformity at the fracture site occurs limitation of wrist motion and forearm rotation, pronation and supination may occur.
Treatment approach depends on many factors, including displacement and stability of the fracture fragments.
Treatment depends on the nature of the fracture, age, activity level, and surgeon’s personal preferences.
Cast may be applied if the bone is well aligned.
If the bone is not well aligned the bone fracture should be reduced, closed or openly, and then a splint or cast may be applied.
Casts are removed about six weeks after the fracture, and physical therapy is often started.
Surgical correction of a fracture may include the use of pins, plates, screws, an external fixator device or casting, or a combination of the above to stabilize the repair.
For torus fractures, a partial bone fracture that usually occurring in children, in which the bone is bent but only broken on one side) a splint may be sufficient and casting may be avoided.
With an undisplaced and stable fracture, non operative treatment involves immobilization.
Initially the wrist is splinted to allow for accompanying swelling and subsequently a cast is applied.
The cast may be placed above the elbow to control forearm rotation, if necessary.
In displaced fractures, the fracture may be manually reduced to reposition the displaced distal radius and maintain this position in a splint or cast.
Casting time varies with different ages, but generally lasts 3-6 weeks.
Displaced fractures in the elderly or those unable to undergo surgery, a short-arm cast is placed for 4 weeks or until the tenderness resolves and than a larger cast is placed for an extended period of time.
Closed management of a distal radius fracture involves some type of anesthesia and manipulation to reduce the fracture after which a splint or cast is placed.
Closed management may be inadequate because of comminution of the fracture and re-displacement and deformity can result.
Non-operative treatment failure is common and is subject to adverse outcomes of stiffness, arthritis, impaired function, and pain.
Fracture often re-displaces to its original position even with casting, such that only 27% – 32% of fractures are acceptably aligned at 5 weeks after closed reduction.
Because of risk of displacement after closed many recommend operative intervention, if the fracture is displaced enough to consider reduction.
Stiffness of the wrist is usual following a fracture of the distal radius.
Complications of casts include:compression leading to compartment syndrome and carpal tunnel syndrome.
Prognosis in children with distal radius fracture treated with casts is usually successful with healing and return to normal function likely.
In younger patients the injury requires greater force and results in more displacement particularly to the articular surface, and accurate reduction of the joint surface is required, to prevent pain, arthritis, and stiffness.
Surgical techniques for repair include: open reduction and intrnal fixation, external fixation, percutaneous pinning, or some combination of the above.