A Monteggia fracture is a fracture of the arm in which the ulna, one of the bones in the forearm, breaks, and the joint with the radial head at the elbow becomes dislocated. This fracture is usually very evident because it causes extreme pain and the patient's range of motion will be limited as a result of the fracture. It can be diagnosed with the assistance of x-rays to visualize the bones and joints in the arm, with the radiographer ideally taking several angles so that the full extent of the injury can be fully visualized.
Hyperextension is a common cause for a Monteggia fracture, as is a blow to the arm. There are several different subtypes of Monteggia fracture, differentiated by the precise location of the break and the nature of the dislocation. Treatment for all types is essentially the same, with the doctor making a note of the type to make sure that the arm is set properly and for future reference.
This fracture is named for Giovanni Battista Monteggia, who described it in the early 1800s. The conservative treatment is casting to immobilize the arm while the ulna and the joint have an opportunity to heal. After the arm has been in a cast for several weeks, x-rays can be taken to confirm that the bones are knitting and that the healing is even. If the bones are not healing or have been pulled out of position, the cast will need to be removed so that the situation can be corrected. For young patients, casting is often sufficient unless the fracture appears to be problematic.
For a severe Monteggia fracture, surgery may be necessary. Surgery can be used to pin the fractured ulna, and to stabilize the joint, if this is deemed necessary. This procedure is generally performed by an orthopedic surgeon, a surgical specialist who has received special training in working with injuries to the bone. After surgery, a cast is usually applied to provide stability during healing, and healing time can take six weeks or more, depending on the patient.
One concern with a Monteggia fracture is that if the healing does not go well, the arm could end up shorter than the other arm. It is also possible that poor healing could predispose the patient to another fracture, which is not desirable. Other issues which can emerge during healing include necrosis, in which bone and tissue die because they are not being supplied with blood, along with infection, which is an especially big risk with an open fracture.