Radial head fractures
From Medical-Wiki
Treatment of radial head and neck fractures have traditionally been treated with closed, conservative management. However, this has recently changed because it often leaves patients with degenerative changes and a loss of mobility.
Clinical presentation of radial head fractures
20% of elbow trauma involves a radial head fracture. Roughly a third of fractures and dislocations involve the radial head and/or neck. A fall onto an extended arm is the most common event that causes damage. The force of impact is carried up the hand through the wrist and forearm to the radial head. The head is then forced against the capitellum. Fractures may be divided into those just distal to the radial head and those involving the other structures of the elbow, distal humerus, or forearm and wrist.
The anatomic factor that complicates healing of radial head fractures is its intra-articular position. This means that the soft-tissue junctures to the upper end of the bone are limited. Since it is these attachments that carry blood supply, avascular necrosis and potential nonunion are common. This also means that removal of bone fragments is crucial to reduce posttraumatic arthritis from mechanical grinding. However, even with bone death, patients usually do well because of the limited function of the radial head.
A factor that should be considered is a congenitally larger radial head, the abnormality associated with congenital radial head dislocations. It is important to recognize this situation because its operative reduction is not indicated.
Radiological evaluation of the radial head
Pediatric radial head fractures may be difficult to diagnose because the head does not ossify until age 4. Thus, adding MRI or ultrasound to x-rays may be needed for an effective evaluation.
A Salter Harris II fracture is the most common type of fracture. Findings indicative of this fracture are the so called positive "sail" as well as posterior fat pad signs. A practitioner should look for anterior or posterior displacement of the radial head or shaft. A Monteggia equivalent is a fracture of the radial head along with an ulnar shaft fracture. [1]
Radiology of the elbow joint can be difficult—particularly with regard to fractures. Use of the so called fat pad sign—a finding that is secondary to a hemarthrosis—as well as making sure that a full elbow series is performed is part of establishing a high degree of sensitivity. Otherwise, MRI or ultrasound may be needed. [2]
Treatment options for radial head fractures
At present, a surgical repair is indicated for all patients except those who have fractures stable enough to allow early motion. Over time, difficulties have developed with surgical excision of the radial head because of migration of the radius. This has even been a problem with replacement of the head with implants. Consequently, anatomic reduction and internal fixation is currently the treatment of choice. [3]
