Overtreatment a cause of complications with pediatric distal radius fractures

Although rare, kids may also experience growth plate injury — a complication not seen in adults.

Children with distal radius fractures face some of the same complications as adults, including malunion, compartment syndrome and acute carpal tunnel syndrome, but these complications are much rarer.

Properly closed reduction and casting typically serve as a definitive treatment for pediatric distal radius fractures, according to John M. Flynn, MD.

“Kids’ ability to remodel their distal radius fracture is substantially better than adults, and the same fracture in an adult, which would require plates and screws or maybe an external fixator, can be put in a cast with … a great result,” Flynn told Orthopedics Today.

He and Robert H. Wilson, MD, recently spoke with Orthopedics Today about these rare complications and how to avoid them.

 Robert H. Wilson, MD
Robert H. Wilson

John M. Flynn, MD
John M. Flynn

Avoiding complications

In some instances, overtreatment may cause complications with pediatric distal radius fractures, Flynn said.

“Complications [may] come from putting pins in when they are not necessary, or from doing unnecessary repeat reductions on a fracture that might remodel successfully on its own,” he noted.

Surgeons also place children at risk for anesthesia complications when they perform unnecessary reductions, Flynn added.

He stressed the importance of creating a well-molded, well-designed cast after achieving fracture reduction. “Probably the biggest source of complications in the malunion or loss of reduction in a kid’s fracture: doing a nice reduction, but not making a good cast.”

According to Wilson, more than 90% of pediatric distal radius fractures are treated nonsurgically. He and Flynn agreed that pinning is necessary for unstable fractures, distal radius fractures with concomitant wrist and elbow fractures, and for fractures that have lost reduction.

“If you have a very displaced fracture, which is reduced, it’s important to follow up in the first 2 to 3 weeks to be on the lookout for loss of reduction. These kids need X-rays in their casts at 1 week and 2 weeks after reduction to watch for loss of reduction,” Flynn said.

Nonphyseal distal radius fracture
This anteroposterior radiograph reveals a nonphyseal distal radius fracture at 3 months after injury. While the patient still has 11° of ulnar angulation, the potential for remodeling is promising, researchers reported.

A lateral radiograph of the same injury
Shown here: a lateral radiograph of the same injury. From this angle, the radiograph reveals a volar angulation of 31°. However, the patient has no functional deficit and the fracture should remodel, according to Wilson.

Images: Wilson RH

Potential complications

Like adults, children may experience malunion with distal radius fractures, which ultimately could affect range of motion – pronation and supination in particular, Flynn said.

Those children with high-energy distal radius fractures could also present with compartment syndrome or acute carpal tunnel syndrome, or they could experience these complications after reduction. “We usually see this more in teenagers – the kid who’s flying down the hill in rollerblades or falls out of a tree,” Flynn said.

Another potential but rare complication with pediatric distal radius fractures is injury to the motor nerve, interosseous nerve, medial ulnar nerve or radial sensory nerve, according to Wilson.

“You can also have a tendon injury, and I’ve only seen this a couple of times where a child will have a tendon entrapped in the bone or a muscle entrapped in the bone and will lose some motion,” Wilson told Orthopedics Today. “If you operate on them, you’ll see that there may be tissue entrapped between the two pieces of bone.”

Displaced distal radius fracture
This patient sustained a displaced distal radius fracture involving the physis, as seen in this anteroposterior radiograph.

Loss of anatomical alignment
This lateral radiograph of the same fracture reveals a loss of anatomical alignment.

Potential growth plate injury

Unlike adults, however, children who sustain distal radius fractures have a slight chance of damaging their growth plate.

“There’s about a 4% risk of growth arrest with a fracture of the distal radius growth plate,” Flynn said. “So maybe one out of every 25 kids might get a growth arrest, but that is pretty unusual. In the younger kids, that would require treatment down the line if the radius and ulna become different lengths.”

Flynn suggested monitoring displaced growth plate fractures, and obtaining X-rays around 6 months to 12 months later to evaluate for signs of growth arrest.

If surgeons recognize a growth arrest in older children, typically they will close the ulnar growth plate, Flynn said. “Or if in a very young kid, where there’s a lot of discrepancy, you can lengthen the radius bone, [which is] a late reconstructive procedure,” he said.

Anteroposterior radiograph
This anteroposterior radiograph demonstrates angulation in a patient with a distal radius fracture, but no significant comminution.

Lateral radiograph
This patient sustained a dorsally angulated nonphyseal distal radius fracture, as seen in this lateral radiograph.

Surgical technique

For pediatric distal radius fractures that require open reduction, Wilson said he performs a slightly different approach with an incision on the radial border of the wrist and forearm.

“I find that approach works better because I have access to the brachial radialis,” Wilson said. “That muscle tendon probably causes the most difficulty with loss of reduction, so I can address that at that time, and it’s right underneath that incision.”

This approach also helps to avoid injury to the radial artery, and provides a straight view of the fracture from the volar and dorsal sides. “If I have an ulnar injury that needs to be addressed, I make an ulnar incision so that the two incisions are 180° apart,” Wilson said.

He suggested using direct vision or X-ray machine assistance to avoid nerve and soft tissue injury when placing pins.

“You could place the pin around or through a nerve that would then lead to a disability or you may pin a tendon and then that may lead to some stiffness or loss of excursion of that tendon, because it might heal down to the soft tissues,” Wilson said. “You want to be careful … to place [the pins] in an area that is not going to either injure or affect the surrounding tissues.”

For more information:
  • John M. Flynn, MD, can be reached at Children’s Hospital of Philadelphia, 2nd Floor Wood Building, 34th and Civic Center Blvd., Philadelphia, PA 19104; 215-590-1533; e-mail: flynnj@email.chop.edu. He has no financial conflicts to disclose.
  • Robert H. Wilson, MD, can be reached at Children’s National Medical Center, 111 Michigan Ave., NW, Washington, DC 20010; 202-884-5000; e-mail: rwilson@Howard.edu. He has no financial conflicts to disclose.