Pediatric Annals

Pitfalls in Fractures

Mercer Rang, MB, FRCS(C); James Wright, MD

Abstract

Everyone says that children's fractures are easy to manage. Like wild animals, they always heal, and any crookedness remodels away. However, this opinion underestimates the severity of the problem. Most wild animals with fractures die. Some children with fractures survive to go on to bad results. Clearly, pediatricians should look after fractures that have good prognoses and leave the others to the orthopedist. What fractures should the pediatrician avoid? HtTw does an orthopedist try to stay out of trouble? Can a pediatrician learn anything from an orthopedist?

Trouble can begin at the moment of diagnosis. What kinds of mistakes can be made and how can they be prevented?

DIAGNOSTIC PROBLEMS

False Negative

There is something wrong but I don't recognize it. Why?

No radiograph taken. Greenstick fractures do not tear the periosteum: there is no hematoma. The limb is not swollen or crooked. Always obtain a radiograph in a child with persisting tenderness after an injury. Children do not have sprains.

No fracture seen: bends of bone. This condition is also known as plastic deformation of bone and is particularly common in the forearm. If the arm looks crooked, this diagnosis should be made. Do not be put off by a radiograph that shows no fracture line. Obtain radiographs of both limbs. Position them so that they are symmetrical.

Cartilage fractures. Children have much growth cartilage, which of course does not show on radiographs. This diagnosis must be based on suspicion, which is alerted by pain, tenderness, and soft tissue swelling on the radiograph. Certain diagnoses of cartilaginous elbow injuries may require an arthrogram.

Type 1 epiphyseal separation. The growth plate is tender to touch, but the x-ray is normal. The diagnosis must be assumed. At the ankle, a stress view can be used to make the diagnosis although there is not much point to it. At the knee, it may mimic a ligament injury (Figure 1).

Displaced forearm fractures in older children may be difficult to hold in a cast. Percutaneous intramedullary fixation with smooth Kirschner wires inserted using an image intensifier may be better.

PROGNOSTIC DIFFICULTIES

Will the fracture remodel? The only fracture that has been scientifically studied is the fracture at the distal end of the radius. It remodels at about Io a month. If a child heals with 30° of angulation and has 3 years of growth ahead the fracture will remodel. If the child has only 1 year of growth ahead the fracture will not. As a general rule it is better to pretend that fractures do not remodel and to accept no malposition greater than would be accepted in the absence of remodeling.

CONCLUSION

Diagnosing and setting a child's fracture is one of the most worthwhile tasks of medicine. Perhaps the best example is that of a child's elbow fracture which, left untreated, tends to produce a stiff, deformed elbow that is unamenable to correction. However, very little skill is required to make the elbow perfect again if this skill is exercised from the outset.…

Everyone says that children's fractures are easy to manage. Like wild animals, they always heal, and any crookedness remodels away. However, this opinion underestimates the severity of the problem. Most wild animals with fractures die. Some children with fractures survive to go on to bad results. Clearly, pediatricians should look after fractures that have good prognoses and leave the others to the orthopedist. What fractures should the pediatrician avoid? HtTw does an orthopedist try to stay out of trouble? Can a pediatrician learn anything from an orthopedist?

Trouble can begin at the moment of diagnosis. What kinds of mistakes can be made and how can they be prevented?

DIAGNOSTIC PROBLEMS

False Negative

There is something wrong but I don't recognize it. Why?

No radiograph taken. Greenstick fractures do not tear the periosteum: there is no hematoma. The limb is not swollen or crooked. Always obtain a radiograph in a child with persisting tenderness after an injury. Children do not have sprains.

No fracture seen: bends of bone. This condition is also known as plastic deformation of bone and is particularly common in the forearm. If the arm looks crooked, this diagnosis should be made. Do not be put off by a radiograph that shows no fracture line. Obtain radiographs of both limbs. Position them so that they are symmetrical.

Cartilage fractures. Children have much growth cartilage, which of course does not show on radiographs. This diagnosis must be based on suspicion, which is alerted by pain, tenderness, and soft tissue swelling on the radiograph. Certain diagnoses of cartilaginous elbow injuries may require an arthrogram.

Type 1 epiphyseal separation. The growth plate is tender to touch, but the x-ray is normal. The diagnosis must be assumed. At the ankle, a stress view can be used to make the diagnosis although there is not much point to it. At the knee, it may mimic a ligament injury (Figure 1).

Figura 1. The false negative problem. This football player was checked during a game, resulting in severe knee pain. The initial film was regarded as normal and an examination undertaken under anesthesia. The diagnosis - a separated epiphysis. The original film was then compared with the normal knee on the other side and the widening of the growth plate could be perceived.

Figura 1. The false negative problem. This football player was checked during a game, resulting in severe knee pain. The initial film was regarded as normal and an examination undertaken under anesthesia. The diagnosis - a separated epiphysis. The original film was then compared with the normal knee on the other side and the widening of the growth plate could be perceived.

Figure 2. An osteochondral fracture accompanying a dislocation of the patella. The fragment should be removed or replaced at arthrotomy.

Figure 2. An osteochondral fracture accompanying a dislocation of the patella. The fragment should be removed or replaced at arthrotomy.

Osteochondral fractures. These are found particularly in the knee from dislocations of the patella. When suspected, order a skyline view (Figure 2).

Fracture line missed. A thin fracture line can be missed if the beam does not aim through the crack. In the ankle, the fracture line may coincide with the border of the fibula and go unseen. This is common in Tillaux's fracture. This, perhaps more than any other fracture, leads radiologists to scan films the next day and phone the occasional patient with the news, "the x-ray we said was normal yesterday seems to have developed a fracture overnight. Please come so that we can check it out." When fracture lines are pointed out they are unmistakable but some go unseen. Oblique films often show fractures that are missed on anteriorposterior and lateral views. These should be ordered routinely for the knee and ankle.

Toddlers' fractures. Hairline fractures of the tibia are sometimes only visible in oblique shots.

Spinal fractures. No fracture line is usually visible. Films show only a change of contour. A film well centered over the fracture is needed to recognize wedged vertebrae (Figure 3).

What can be done to avoid the false negative risk?

Thorough clinical examination. AU parts of the limb- -both above and below the obvious fracture - should be examined.

Clinical suspicion and a willingness to believe history and signs over a radiograph can help eliminate false negative results. If the film shows no fracture that does not rule out injury.

Figure 3. A false negative radiograph. After a flexion injury this child had a lot of neck pain, but films showed no injury. He was given a ruff, and an appointment to return. Because of persistent pain another film was taken, which showed the displacement. He had sustained an avulsion of the cartilage apophysis of the spinous process. He came to fusion. The lessons to be learned are: |1) a proportion of injuries that you see are not what you would think, and |2) every branch of medicine needs a fail-safe system.

Figure 3. A false negative radiograph. After a flexion injury this child had a lot of neck pain, but films showed no injury. He was given a ruff, and an appointment to return. Because of persistent pain another film was taken, which showed the displacement. He had sustained an avulsion of the cartilage apophysis of the spinous process. He came to fusion. The lessons to be learned are: |1) a proportion of injuries that you see are not what you would think, and |2) every branch of medicine needs a fail-safe system.

Figure 3. A false negative radiograph. After a flexion injury this child had a lot of neck pain, but films showed no injury. He was given a ruff, and an appointment to return. Because of persistent pain another film was taken, which showed the displacement. He had sustained an avulsion of the cartilage apophysis of the spinous process. He came to fusion. The lessons to be learned are: |1) a proportion of injuries that you see are not what you would think, and |2) every branch of medicine needs a fail-safe system.

Figure 3. A false negative radiograph. After a flexion injury this child had a lot of neck pain, but films showed no injury. He was given a ruff, and an appointment to return. Because of persistent pain another film was taken, which showed the displacement. He had sustained an avulsion of the cartilage apophysis of the spinous process. He came to fusion. The lessons to be learned are: |1) a proportion of injuries that you see are not what you would think, and |2) every branch of medicine needs a fail-safe system.

Well centered fìlms. A missed fracture may mean that the radiograph is of such poor quality that nothing shows. Sometimes a missed fracture is the result of a scout film that was ordered; eg, "query leg and thigh." If the ankle is fractured and the radiograph includes the whole limb, distortion can cause the injury to be missed. Therefore, radiograph the site of the injury and avoid wide angle pictures. Insist on true anteriorposterior and lateral radiographs. Obliques can be deceiving when trying to decide on the amount of angulation.

Take radiographs of the uninjured side. Children are symmetrical, so if there is any doubt there is always another side for comparison. It is not necessary to do this every time a bone is x-rayed, but sometimes it is helpful.

Stress radiographs or computerized tomography scans occasionally serve to negate a false negative diagnosis.

False Positive

What looks like a fracture but really is not does not present a very serious problem. Growth plates are sometimes mistaken for fractures. The apophysis of the base of the 5th metatarsal fools a few physicians each year (Figure 4). Dislocations of the shoulder are sometimes diagnosed, but children tend to separate an epiphysis before they dislocate a bone or sprain a ligament. The vascular canal of a bone may also be mistaken for a fracture.

Figure 4. Is the line on the radiograph a fracture or not? The growth plate of the 5th metatarsal is commonly confused with a fracture. The plate is longitudinal and a fracture is transverse. Here the plate and the fracture are coexistent.

Figure 4. Is the line on the radiograph a fracture or not? The growth plate of the 5th metatarsal is commonly confused with a fracture. The plate is longitudinal and a fracture is transverse. Here the plate and the fracture are coexistent.

Mistaken Diagnosis

It looked like A but it was really B. There is no doubt that something is wrong but the injury is not what it seems.

Child abuse used to be recognized only as a fracture. Today it is on everyone's mind and is unlikely to be missed. In every child under 1 year old a fracture should be viewed as possible evidence of child abuse until proved otherwise. Acute fractures are as common as multiple fractures in various stages of healing.

Figure 5. An example of an injury that was overlooked because a rubric was not followed. The rubric is: "Check that a tine drawn through the radius passes through the center of the capitellum."A few months later this deformity increased and a repair was carried out.

Figure 5. An example of an injury that was overlooked because a rubric was not followed. The rubric is: "Check that a tine drawn through the radius passes through the center of the capitellum."A few months later this deformity increased and a repair was carried out.

Monteggia's fracture dislocation is a fracture of the ulna with a dislocation of the radial head. The dislocation is easily missed, and then always comes back to haunt the person who missed it. Rubric: always include the elbow and wrist on forearm fractures. Always draw a line through the radius and check that it passes through the radial head on both the anteriorposterior and lateral projections (Figure 5).

Coalition is occasionally mistaken for recurrent ankle sprain. The symptoms of these conditions are much the same. The teenager presents with pain in the sinus tarsi after a minor injury. An ankle x-ray is taken and is normal. Tarsal coalition does not show up on an ankle film. An oblique film of the foot or a calcaneal view must be obtained.

Some situations are like nothing you have encountered before. This is a time to read, consult a colleague, or take a continuing medical education course.

Figure 6. Newer techniques are not usually needed for fracture care but they do serve to show that a few millimeters of displacement in three planes adds up to a lot when you look at the whole joint.

Figure 6. Newer techniques are not usually needed for fracture care but they do serve to show that a few millimeters of displacement in three planes adds up to a lot when you look at the whole joint.

Mistake in Quantity

Errors in diagnosing displacement usually result from underestimating the adversary; thinking that a fracture has little displacement when it has too much to leave unreduced (Figure 6). Every fracture is different, which makes diagnosis difficult for pediatricians. For a fracture of the shaft of the femur 3 cm of displacement may be acceptable, but tor a fracture of the lateral condyle of the humerus any displacement at all is a reason for internal fixation.

Fracture of the lateral condyle of the humerus is sometimes so little displaced that oblique films are needed to find the fracture line. Nonetheless, it is just as dangerous as a widely displaced fracture. It will migrate and go on to nonunion (Figure 7).

Supracondylar fractures of the humerus can be apparently undisplaced and left to heal in position. When they heal, however, the child has a varus deformity. This can happen without the fracture slipping. The degree of deformity is hard to recognize unless carefully positioned films are taken.

Sometimes the propensity for trouble a fracture can cause is underestimated. The undisplaced greenstick fracture of the proximal tibia has been involved in a number of lawsuits. On the radiograph it does not appear serious, but over the months that follow the leg develops gross unilateral knock knee (Figure 8). The reason for this is controversial.

Fractures of the distal radius commonly seem undisplaced at the time the cast goes on but manage to angulate during the first 2 weeks after they have been hidden from view inside the cast. When the cast is opened all the birds begin to sing, "wasn't that a horrid thing." These fractures deserve their evil reputation.

Elbow fractures in children under 4 years of age are the most deceptive. These children have a small metaphyseal fragment of bone and a lot of cartilage. A little piece of bone can separate along with a large piece of cartilage. The cartilage can be much more displaced than the bone, and the only way to find out is to do an arthrogram. These are not fractures for beginners even if they appear to be straightforward. Arthrography may change the diagnosis made on plain films 40% of the time.

Elbow dislocation is generally accompanied by a fracture, which may be difficult to see. The displaced medial epicondyle may be jammed in the joint.

Mistakes in Human Relations

When I am tired and confronted with a child in pain, I know that I should move slowly and handle everything tenderly even though my instincts tell me to do what I have to do and finish as quickly as possible. If the parents and child are antagonized at the first meeting then nothing will go well in the future. Soon, minor episodes of thoughtlessness will become letters of complaint to hospital administrators.

Recommending that parents seek a second opinion may have two negative results. Parents may feel that your opinion is so tentative that they lack confidence or that the treatment plan decided upon is so rigid that they have no input.

TREATMENT

Indications for Plaster Immobilization

Most fractures are covered in plaster. Holding the injury still relieves pain. Minor ankle injuries will heal whether or not they are immobilized, but compare these two scenarios - both involve an undisplaced type 1 injury of the distal fibular epiphysis. Joan is given a tensor and a pair of crutches. She returns after 2 days because her toes are swollen and blue. She had the tensor so tight it was obstructing circulation. Two days later she phones. The ankle feels terrible and she wants to see you urgently. On examination her ankle looks no different than any other sprained ankle. You tell her the ankle is healing as it should - be patient. You never see her again because she goes to someone else. Tammy has a below knee cast put on right away. She is soon walking on it and continues her regular life. You see her the day the cast comes off and then probably not again.

Figure 7. The quantitative dilemma. How much is too much? For intraarticular fractures start with the premise that exact reduction and internal fixation is best. Fractures of the lateral condyle are prone to displace in a cast and proceed to nonunion.

Figure 7. The quantitative dilemma. How much is too much? For intraarticular fractures start with the premise that exact reduction and internal fixation is best. Fractures of the lateral condyle are prone to displace in a cast and proceed to nonunion.

Why the difference? Joan is uncomfortable and unable to function. She expects an uncasted ankle to be normal. Tammy is pain free, and the cast tells her that she has an injury that will take time to heal.

There are, however, problems with using plaster casts on children. Plaster tends to slip tiff children's characterless limbs. Use tincture of benzoin to increase adherence. Above knee and above elbow casts are recommended to help hold the casts on. The plaster should be molded to grip above the condyles.

Indications for Reduction

Angular and rotatory deformities should be reduced; closed reduction is usually suitable. Many fractures in children will remodel and experience is needed to know which can be left to remodel and which need reduction. What remodels? (1) almost anything in toddlers; (2) fractures at the rapidly growing end of a bone (the wrist and the neck of the humerus); and (3) fractures in the plane of movement of a joint (Figure 9). The valgus and varus do not remodel; neither do rotation and joint surfaces.

Indications for Open Reduction and Internal Fixation

There are few fractures in children that require open reduction, but those that do, really need it. Sometimes, it seems that closed reduction is sufficient but this is a mistake. Inexorably, they become disasters. All fractures involving the joint surface require primary open reduction. These include type 4 fractures of the growth plate. Reduction is needed to ensure a good range of movement as well as continuing growth.

PROBLEMS WITH FOLLOW-UP

Some fractures - particularly forearm fractures - are inclined to slip in the cast. Slippage can only be discovered if radiographs of the child are taken every week. If appointments are skipped (or not offered), then displacement is not noticed until the cast comes off. Depression radiates and, if it is beyond the power of remodeling, the fracture will need to be reset and another cast applied.

Figure 8« The amount of displacement is not always a guide to the outcome. A greenstick fracture of the proximal tibia usually has minimal displacement, but a year or two later produces obvious knock knee because of a growth disturbance.

Figure 8« The amount of displacement is not always a guide to the outcome. A greenstick fracture of the proximal tibia usually has minimal displacement, but a year or two later produces obvious knock knee because of a growth disturbance.

Fractures with a special reputation for developing a bony bridge that affects growth should have radiographs 6 months after injury. This makes it possible to pick up a growth disturbance in time to correct it by excising the bridge.

The worst problem of follow-up is compartment syndrome. Pain dominates the picture; the child is inconsolable for several days. When everything in the compartment is dead, the pain goes away and the child seems better.

HINTS ABOUT SPECIFIC FRACTURES

Proximal humeral fractures do well when they heal in the displaced position. A few fractures in adolescents at the end of growth should be reduced. Percutaneous pinning should be used to avoid the risk of a brachial plexus stretch injury.

Supracondy for fractures are unstable and prone to compartment syndrome. Percutaneous pinning and immobilization in extension have eliminated a lot of the danger. When the arm is pulseless, reduction will usually restore the circulation. Only when the arm remains cool and pulseless after reduction should exploration be undertaken.

Fractures of the shaft of the femur in combination with a head injury commonly require intermedullary nailing.

Open fractures, even a tiny puncture wound, should be debrided using an anesthetic because bacteria are small enough to enter the wound and produce a devastating infection (Figure 10).

Knee hemarthrosis in boys coming off a bike are generally produced by fractures of the tibial spine. The fragment has wings of cartilage which facilitate closed reduction. Occasionally, a meniscus is interposed necessitating open reduction.

Figure 9. This is the fracture most likely to displace in children. It also has the greatest ability to remodel. However, parents do not think much of having a child with a temporarily crooked wrtst. To avoid this eventuality immobilize the fracture in full pronation or full supination and do not leave it in the midposition.

Figure 9. This is the fracture most likely to displace in children. It also has the greatest ability to remodel. However, parents do not think much of having a child with a temporarily crooked wrtst. To avoid this eventuality immobilize the fracture in full pronation or full supination and do not leave it in the midposition.

Proximal tibial fractures, even when undisplaced, should be reduced and held in plaster with the knee in full extension. This minimizes the risk of valgus developing.

Ankle fractures in adolescents with partially closed growth plates result in complex fractures: Tillaux's and triplane fractures. Many can be treated by closed reduction, with the foot rotated internally, and held in a cast with the knee flexed 90°. A computerized tomography scan of the casted reduced ankle may be needed to ascertain the position of the fracture.

Figure 9. This is the fracture most likely to displace in children. It also has the greatest ability to remodel. However, parents do not think much of having a child with a temporarily crooked wrtst. To avoid this eventuality immobilize the fracture in full pronation or full supination and do not leave it in the midposition.

Figure 9. This is the fracture most likely to displace in children. It also has the greatest ability to remodel. However, parents do not think much of having a child with a temporarily crooked wrtst. To avoid this eventuality immobilize the fracture in full pronation or full supination and do not leave it in the midposition.

Figure 10. Even small puncture wound must be debrided under anesthesia. This child had an open forearm fracture, which was undisplaced- The wound was small so it was cleaned up in the emergency room and a cast was applied. This film taken a few days later shows air in the tissues - gas gangrene. The arm was amputated. This scenario did not take place in a small country hospital many years ago. It happened recently in a city hospital. Settling this case cost every orthopedic surgeon in the country $3.000.

Figure 10. Even small puncture wound must be debrided under anesthesia. This child had an open forearm fracture, which was undisplaced- The wound was small so it was cleaned up in the emergency room and a cast was applied. This film taken a few days later shows air in the tissues - gas gangrene. The arm was amputated. This scenario did not take place in a small country hospital many years ago. It happened recently in a city hospital. Settling this case cost every orthopedic surgeon in the country $3.000.

Displaced forearm fractures in older children may be difficult to hold in a cast. Percutaneous intramedullary fixation with smooth Kirschner wires inserted using an image intensifier may be better.

PROGNOSTIC DIFFICULTIES

Will the fracture remodel? The only fracture that has been scientifically studied is the fracture at the distal end of the radius. It remodels at about Io a month. If a child heals with 30° of angulation and has 3 years of growth ahead the fracture will remodel. If the child has only 1 year of growth ahead the fracture will not. As a general rule it is better to pretend that fractures do not remodel and to accept no malposition greater than would be accepted in the absence of remodeling.

CONCLUSION

Diagnosing and setting a child's fracture is one of the most worthwhile tasks of medicine. Perhaps the best example is that of a child's elbow fracture which, left untreated, tends to produce a stiff, deformed elbow that is unamenable to correction. However, very little skill is required to make the elbow perfect again if this skill is exercised from the outset.

10.3928/0090-4481-19890101-09

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