Forearm anatomy 

The forearm is made up of the radius and the ulna. It’s main function is to allow us to rotate our arms— it needs to rotate down for activities like typing and texting, and rotate up for carrying heavy objects. For the forearm to rotate correctly, the bones need to be straight enough so that the radius bone can rotate over the ulna bone.

There are growth areas at the top and bottom ends of the forearm. The bottom growth areas near the wrist experience the most growth, and are also more likely to be injured.

Forearm Fractures

Forearm fractures are quite common in children of all ages and are typically the result of a fall. Fractures that occur in children age 10 and younger often heal well without surgery and are treated with a cast for approximately six weeks.

However, sometimes, the fractures move within the cast into a position that can decrease future function. In this case, your doctor may recommend surgically placing a temporary rod in either one or both bones in the forearm. The rods would stay inside the bone for approximately three to six months, and would then be removed surgically.

All attempts are made to treat a preteen's or adolescent's fracture with a cast. But unfortunately, their forearm fractures often require more than a cast for the following reasons:

  • Older children and have less growth left. The bones must heal straight to ensure they can properly use them in the future
  • The lining around older bones is not as thick, which makes it easier for the broken bone to move around in the cast and not heal well
  • Older children also have bigger, stronger muscles than younger children; muscles are more likely to cause the fracture pieces to move around in the cast, disrupting healing

Once the fracture can be removed from the cast, your child may need to wear a brace for a few weeks. Since fractures that occur in the middle of the forearm have a 5 percent chance of breaking again within the first 18 months after the initial break, it’s important to keep the forearm protected for as long as possible.

Monteggia fractures

A monteggia fracture (pronounced mon-tej´ē-ă) is a common injury that occurs when a child falls and reaches out a hand to break a fall. The fracture is in the ulna, one of the bones of the forearm, along with a dislocation of the radiocapitellar joint, which helps to move the forearm. The force of the fall, paired with the fracture, forces the head of the radius, the other bone in the forearm, to dislocate from the elbow joint.

Distal radius fractures

Distal radius fractures (broken wrists) are extremely common in children. The break occurs at the bottom end of the bone typically where it’s widest in the metaphysis, or at the growth area (physis). Many of these fractures can be treated with a cast for three to four weeks; others must be put in place (reduced) and then placed in a cast. The most severe fractures need to be surgically treated.

Distal radius physis fractures

Fractures of the growth plate of the distal radius are also very common. These breaks are treated differently than other types of fractures, mostly because of the risk of future growth problems, which depend on the severity of the initial injury.

Distal radius physeal fractures heal relatively quickly. Most children are casted for six weeks at the most. Often, a long cast is applied first to prevent the forearm from rotating. Then, once the fracture has undergone its initial healing (somewhere between two to four weeks), your child will receive a new cast that ends below the elbow for the duration of treatment. A follow-up visit may be necessary six to nine months after the injury to evaluate the bone’s growth ability.

If your child has a break through the growth area, and the bones are separated away from each other, the bone may need to be realigned under heavy sedation. Since too many attempts to manipulate the bones can damage the growth plate, we do this very carefully. And, we won’t move it once it begins the initial stage of healing (typically after the first week), because it’s more likely to hurt future growth than help. The fracture and the bone will often straighten itself out over time.