Pediatric Fractures

Overview

what it is and why it matters

Children's broken bones are not just smaller versions of adult fractures, they behave differently. Kids' bones still have soft growth plates (cartilage zones near the ends where new bone is forming), they bend more before they break, and they heal and remodel themselves to a degree adult bone cannot touch. When a fracture goes through or near a growth plate, your provider looks closely at how it relates to the growth plate, because that is what predicts how it will heal. Most growth-plate fractures heal well in a cast. Some run into the nearby joint surface and have to be put back in exactly the right position, which often means surgery. A crush of the growth plate itself carries the real risk of the bone stopping its growth on that side.

Kids' bones can also bend or buckle without snapping all the way through, patterns you basically do not see in adults. In one, a bone cracks on one side while bending on the other; in another, the bone crinkles like a soda can. Both heal well in a cast without surgery.

Salter-Harris in plain English

what each type means for healing

The growth plate (called the physis) is the cartilage zone near each end of a child's long bone where new bone is forming. Because cartilage is softer than bone, it's the weak link, and many pediatric fractures pass through or near it. The Salter-Harris classification describes how the fracture relates to the growth plate, in five increasingly bad-news patterns:

Type I, the fracture line runs through the growth plate, separating it from the shaft. Often invisible on X-ray (the growth plate is cartilage, which doesn't show), so the diagnosis is sometimes made on tenderness alone. Heals reliably in a cast.
Type II, the most common pattern. The fracture goes through the growth plate and breaks off a small wedge of the shaft on one side. Heals well in a cast in nearly all cases.
Type III, the fracture goes through the growth plate and exits through the joint surface. Now we're worried about two things: cartilage damage (cartilage doesn't regenerate) and growth disturbance. Often needs surgery to put the joint surface back together exactly.
Type IV, the fracture crosses the growth plate and continues across both the shaft and the joint surface. Same surgical concerns as Type III, with a higher rate of growth arrest.
Type V, a crush injury to the growth plate itself, no separate fragment. Often missed at first because the X-ray looks bland; diagnosed in retrospect when the bone stops growing on one side. The most likely of the five to leave a permanent length or alignment problem.

The take-home: Types I and II are usually a cast. Types III and IV are usually an operation. Type V is bad news that announces itself months later. Any pediatric fracture near a growth plate gets specifically watched for growth disturbance over the following six to twelve months.

Where kids break bones most often

five sites that account for most of pediatric orthopedics

The same five fracture sites account for the bulk of what we see in pediatric orthopedics:

Wrist (distal radius) fractures, by far the most common pediatric fracture. Often a buckle pattern in younger kids, and a growth-plate fracture in older ones. Most heal in a short cast or removable splint, and your child's provider will give you the expected timeline for their specific fracture.
Both-bone forearm fractures, the radius and ulna break together, classically from a fall onto the hand. The fracture remodels well in younger kids; alignment matters more in adolescents whose growth plates are nearly closed.
Fractures just above the elbow, classically from a fall onto an outstretched hand in a kid age four to seven. The badly displaced ones are urgent, because important blood vessels and nerves run right under the fracture, so we watch the pulse and the color of the hand closely. These often need surgery to set the bone and hold it with pins.
Clavicle fractures, common in birth trauma, in toddlers, and in older kids who fall onto the shoulder. Almost always heal in a sling without surgery, even when they look pretty deformed. Remodeling is so reliable here that the cosmetic bump usually disappears over a year.
Thigh-bone (femur) fractures, from higher-energy injuries. How they are treated depends a lot on the child's age, ranging from a cast in the youngest children to surgery to stabilize the bone in older ones.

Healing and remodeling, kids' superpower

why some imperfect alignments are still acceptable

Pediatric bone heals fast and remodels itself in a way adult bone cannot. A young child can heal a femur fracture far faster than an adult does for the same injury. Beyond the speed, the more remarkable part is remodeling: a child's bone, while it's still growing, will gradually straighten itself out from a position that wasn't perfect at the time of healing. The closer the fracture is to a growth plate and the more years of growth a child has left, the more remodeling potential they have.

This is why a forearm fracture in an eight-year-old can be accepted with a few degrees of angulation that we would never accept in a 16-year-old or an adult. The eight-year-old's body will fix it. The 16-year-old's growth plates are nearly closed and the position is more or less the position that's locked in. Pediatric fracture care is built around knowing what each age group can remodel and what they can't, and only operating when the alignment is outside what time and growth will fix.

When to worry

red flags after a kid's fracture

Most pediatric fractures heal uneventfully. A few situations need urgent attention rather than a clinic appointment next week:

Severe pain that's getting worse rather than better, especially with fingers or toes that look pale, blue, or feel numb. This is the picture of compartment syndrome, pressure building up inside a forearm or leg compartment to the point that blood flow is choked off. It's an emergency. Tight casts also produce this picture and need to come off urgently.
Inability to wiggle fingers or toes, or new numbness, suggests a nerve has been pinched by the fracture or a swelling cast. Not always urgent, but always evaluated promptly.
Fever, redness, drainage, or worsening pain at a surgical site, possible infection. Call the office.
A fracture that doesn't fit the story, the mechanism described doesn't match the injury, multiple fractures in different stages of healing, or specific patterns (corner fractures, posterior rib fractures in infants, spiral femur fractures in non-walking children) raise concern for non-accidental injury. We work this up sensitively but thoroughly when the picture is concerning. It is part of caring for kids well.

Symptoms

what you or your child may notice

Pain at the injury site, your child will cry or pull away when you touch the area, or refuse to move it at all.
Swelling and bruising, the area puffs up quickly, sometimes within minutes, and may turn purple.
Not using the injured limb, a toddler stops crawling or walking; an older child cradles the arm or won't put weight on the leg.
Visible bend or deformity, the arm or leg looks crooked compared with the other side.
Tenderness right at the growth plate, pressing directly over the end of the bone (near the joint) reproduces sharp pain, suggesting the fracture runs through the growth plate.

Diagnosis

exam first, imaging second

X-rays in two views are the starting point. Because growth plates can look just like fracture lines on a kid's X-ray, we sometimes also X-ray the uninjured side to compare. A CT scan adds detail when the break runs into a joint surface. An MRI shines for growth-plate injuries because it shows the cartilage that doesn't show up on X-ray.

How We Treat It

what we try first, in order

The good news for parents: most children's fractures heal without surgery. Because kids' bones reshape themselves as they grow, we can accept small imperfections that would never be acceptable in an adult and let time and growth finish the job. The steps below are listed in the order care usually progresses, from the splint that goes on first to the cast that carries the bone the rest of the way.

Splinting First

Right after the injury we use a splint instead of a full cast, because the leg or arm needs room to swell. Once the swelling settles over a few days, we swap it for a cast.

Cast Immobilization

Most kids' fractures, including most growth-plate injuries, heal beautifully in a cast. Children's bones reshape themselves as they grow, so they often correct small alignment imperfections on their own. Children's fractures generally heal faster than an adult's, and your child's provider will give you the expected timeline for their specific injury.

Surgical Options

if non-operative care isn't enough

Surgery is reserved for fractures that cross the joint surface and need to be put back in exactly the right place (Salter-Harris III and IV), fractures pressing on a nerve or blood vessel, unstable forearm breaks, and most thigh-bone (femur) fractures in older children.

Frequently Asked

questions we hear in clinic

Will my child's bone heal crooked?

Usually not, even when it looks bent at first. A child's bone reshapes itself as it grows, gradually straightening out a position that wasn't perfect at the time of healing. The closer the fracture is to a growth plate and the more years of growth a child has left, the more they can remodel. That is why a forearm fracture in an eight-year-old can be accepted with a few degrees of angulation that we would never accept in a 16-year-old or an adult, the younger child's body will fix it.

Does a growth-plate fracture mean my child will stop growing?

Most do not. The diagnosis depends on the Salter-Harris type. Types I and II, the most common, usually heal beautifully in a cast. Types III and IV cross into the joint surface and need to be put back exactly. Type V is a crush of the growth plate itself and carries the real risk of the bone stopping its growth on that side. Any fracture near a growth plate gets specifically watched for growth disturbance over the following six to twelve months.

Will my child need surgery?

Most children's fractures heal without surgery. Surgery is reserved for fractures that cross the joint surface and have to be put back in exactly the right place (Salter-Harris III and IV), fractures pressing on a nerve or blood vessel, unstable forearm breaks, and most thigh-bone fractures in older children.

Why a splint first instead of a cast right away?

Right after the injury the leg or arm needs room to swell, so we start with a splint. Once the swelling settles over a few days, we swap it for a cast. A cast that is too tight can choke off blood flow, which is why we do not apply one over a freshly swelling limb.

How long does a kid's fracture take to heal?

Pediatric bone heals faster than adult bone. A young child can heal a femur fracture far faster than an adult does for the same injury, and a wrist buckle fracture typically heals in a short-arm cast or removable splint. Your child's provider will give you the expected timeline for their specific fracture.

What should make me call the office or go to the ER?

Severe pain that is getting worse rather than better, especially with fingers or toes that look pale or blue or feel numb, can signal compartment syndrome and is an emergency. A cast that has become too tight produces the same picture and needs to come off urgently. New numbness or an inability to wiggle fingers or toes should be evaluated promptly, and fever, redness, drainage, or worsening pain at a surgical site should prompt a call to the office.

Why did the X-ray look normal when my child is clearly hurt?

Growth plates are made of cartilage, which does not show up on X-ray, so some fractures through the growth plate (Salter-Harris I, and the crush-type Salter-Harris V) can be invisible on the first film. Because growth plates can also look like fracture lines, we sometimes X-ray the uninjured side to compare, and an MRI can show the cartilage that does not appear on X-ray.