Understanding the Severity of Perthes Disease

There is a condition that affects some children called Legg-Calvé-Perthes or Perthes disease. It involves a loss of blood supply and the death of bone at the top of the femur (thigh bone). The condition can range from mild-to-severe. The round head of the femur may collapse and shift and become more oval shape. Later in life, these children can develop early and sometimes severe hip arthritis.

Treatment depends on a careful classification to determine severity. But there isn’t one standard classification method used by everyone. Instead, there are numerous ways to classify this condition. The authors of this article review the various classification methods and make recommendations for the most useful one to use based on research studies.

Classification of any condition like Perthes is useful because it helps give a picture of what is happening for each individual patient. Using a classication system allows us to look at groups of patients with Perthes to predict results with and without treatment.

It’s best to have one classification system to study all patients. Right now, there are a half dozen methods described in the literature. There’s the Catterall, Salter-Thompson, lateral pillar (Herring), Mose, and Stulberg classifications. These methods all rely on X-ray evaluation of the hip.

The Catterall classification takes a look at the location and amount of bone collapse. Patients are placed in one of four groups based on the specific effects of Perthes on the epiphysis (growth center). The presence of collapse, degeneration, absorption, and regeneration are described with this system.

The Salter-Thompson classification model is much simpler. There are only two groups based on how much of the femoral head is involved (less than half or more than half). The Stulberg classification places children in one of three categories based on the shape of the femoral head. The Stulberg classification method has been tested, modified, and eventually expanded to include five groups instead of the original three.

Herring also took Stulberg’s original three-group classification method and revised it and published several studies. Focus has shifted now to using the Herring (lateral pillar approach) because it has good interobserver reliability. In other words, different radiologists using X-rays to classify the disease using this method came up with the same results.

There is another type of classification based on bone scintigraphy. Bone scintigraphy looks at the distribution of blood flow and active bone. It helps show blood flow to and through the bone and shows places throughout the skeletal system where the bone is actively metabolizing.

The advantage of bone scintigraphy is that changes in bone metabolism show up on the bone scan before structural changes would appear on an X-ray. Conditions such as fractures, infections, tumors, and Perthes can be recognized with a bone scan long before they can be seen with plain radiographs.

Scintigraphy is not used routinely because it is an invasive test. It requires injecting radioactive tracers in the child’s blood. It is also much more expensive than plain radiographs (X-rays).

In summary, taking a look at all the classification methods and comparing final results is a good way to see which approach is the most accurate. Although the Catterall classification has been used most often in the past, there’s a shift now toward using the Herring (lateral pillar) method instead. The Herring method has been shown to have good interrater reliability as well as the ability to predict final outcomes.

The author of this review says there is still room for improvement in adopting a standard way to classify Perthes disease based on X-rays. For example, it’s very easy to have slight differences in the child’s hip position when the X-ray is taken. What the radiologist sees of the hip can be very influenced by a subtle difference in hip rotation. The child could also be standing or lying down and that makes a difference.

What Happens in Children with Legg-Calvé-Perthes Disease When They Become Adults?

That’s a long title but it reflects a long journey from childhood into adult years with a condition called Legg-Calvé-Perthes (LCP) disease. What happens to these children with and without treatment? How does the disease affect them as adults? These are the questions addressed in this review article on the natural history of LCP.

Legg-Calvé-Perthes disease affects the hip (or hips) of children between the ages of four and eight most often. But the disease can show up later in the teen years. The condition develops after there has been an interruption in blood flow to the growing centers of the hip.

Those growth centers (called the capital femoral epiphyses) are located at the round top of the femur (thigh bone). Without enough blood, the bone starts to die, a process referred to as necrosis.

The dead bone cells are eventually replaced by new bone cells but this can take several years. In the meantime, pressure and load from weight on the bone causes it to flatten. The smooth, round head of the femur that sets inside the hip socket (acetabulum) becomes oval-shaped (ovoid) or misshapen. Instead of fitting tightly inside the acetabulum, bone extrudes or expands outside the confines of the socket.

In severe cases (and especially in children who develop this condition after age eight), the deformed hip may develop early arthritis. In a small number of children who don’t have signs of LCP until into their teen years, the chances of full recovery is very slim. That’s because the bone never gets the full blood flow back that it needs to remodel.

In all cases, the more flattened the bone and the more misshapen the round femoral head becomes, the more likely degenerative arthritis will occur at an early age. The reason for this is that joint surfaces need to be evenly matched or congruent. Without this tight fit, the bones rub against each other unevenly. Over time with repeated movements, the joint degenerates where the greatest amount of pressure has been applied.

How does knowing the natural history and prognosis of Legg-Calvé-Perthes disease help children and teens with this problem? Studies show that isotope and MRI scans show the pattern of lost blood even before X-rays. Since the disease is self-limiting (the body heals itself), identifying this problem early may help.

Giving the hip every opportunity to heal itself by limiting load on the joint may prevent the flattening of the femoral head and deformity that can develop. The only problem is — it can take two to four years for the necrotic bone to get resorbed and replaced by new bone. And in some cases, new bone never forms. Instead, there is new granulation (healing) tissue, but that area doesn’t harden into bone, it just forms cartilage.

The physician will be able to follow the healing process using X-rays and MRIs. These imaging studies show the four stages of LCP. These four stages are 1) necrosis (death of bone cells), 2) fragmentation (breakdown of dead bone), 3) regeneration of bone (new bone forms), and finally, 4) healed replacement of normal bone tissue.

Fractures of the weakened bone develop in about one-third of the children during the fragmentation phase. That’s when the head of the femur becomes deformed and extrusion (spread of bone out from under the hip socket) occurs. Fractures can also develop when new bone is forming. X-rays help show this as well.

There are some other complications that can develop during healing. During the fragmentation stage, there is the possibility of bone cysts forming and osteoporosis (brittle, weak bone) developing. These problems resolve slowly as the full healing process proceeds from beginning to end.

Fusion of the growth plate too soon can also occur. There is a poorer prognosis if this happens. The neck of the femur (connects the long shaft of the bone to the round head) stops growing. The effect of this complication is that the affected leg will be shorter than the other leg.

Along with changes on the femur side of the hip, there can also be changes in the acetabular (socket) side. Thickening of the joint cartilage as well as changes in the shape and size of the acetabulum can affect final outcomes.

In summary, the greater the degree of blood loss and bone changes associated with Legg-Calvé-Perthes (LCP) in childhood, the worse the final results as an adult. Age is the determining factor in this condition. Recovery is more likely in children under the age of eight. Development in teens is infrequent but with a poorer prognosis.

But the good news is that many children have mild LCP, and they are able to heal and recover fully even without treatment. The hip actually remodels itself and remains smooth moving. Early degenerative hip arthritis does not always occur and these children have no hip problems in adulthood related to their childhood history of Perthes disease.

Legg-Calvé-Perthes Disease: One Single Cause or Multifactorial?

For 100 years now, since Legg-Calvé-Perthes (LCP) disease was first described, physicians have been searching for the cause of this condition. In this article, Dr. Harry Kim, an orthopedic surgeon from Texas Scottish Rite Hospital for Children reviews the current thinking on the etiology (cause) of LCP.

Perthes disease is a condition that affects the hip in children between the ages of four and eight. The condition is also referred to as Legg-Calve-Perthes disease in honor of the three physicians who each separately described the disease.

In this condition, the blood supply to the growth center of the hip (the capital femoral epiphysis) is disturbed, causing the bone in this area to die. The blood supply eventually returns, and the bone heals.

How the bone heals determines what problems the condition will cause in later life. Perthes disease may affect both hips. In fact, 10 to 12 percent of the time the condition is bilateral (meaning that it affects both hips). This condition can lead to serious problems in the hip joint later in life.

Clearly the problem is one of blood loss called ischemia. The area affected most is the head of the femur (thigh bone). This has been confirmed with today’s modern imaging studies. As a result of this blood loss, the bone dies and starts to collapse. Soon the smooth, round head of the femur starts to flatten and deform.

But what causes the decreased vascularity (blood flow) and can it be stopped before the damage is done? Dr. Kim tells us that many experts believe LCP is the result of several or even many factors. Another way to say this is that LCP is a multifactorial disease with both genetic and mechanical contributing
factors.

On the genetic side, it’s possible some children are more susceptible (more likely) than others to develop this problem. But it takes one or more “triggers” (environmental or external factors) to start the process.

Let’s back up and take a little closer look at the proposed causes of LCP. there are families with many members who have LCP as a result of a mutation in a particular gene. The affected gene controls the strength of collagen tissue. One miscoding in the gene and the hip joint cartilage and its blood vessels don’t form correctly.

Another biologic factor that contributes to some cases of LCP is a protein deficiency. Without the proper sequencing of these important proteins, affected individuals have abnormal coagulation (blood clotting). Abnormal blood clotting can cut off blood supply to the femoral head.

Other potential biologic factors that may be linked with LCP disease include low levels of abnormal insulin-like growth factor (IGF-1), low birth weight, and short body length at birth. Exposure to nicotine and other chemicals from tobacco is an important factor recently discovered. Likewise LCP may be triggered by exposure to tobacco if the mother smokes during pregnancy or the child is exposed to second hand smoke during infancy and early childhood.

With this much information in hand, further studies were done. Now there is some evidence that LCP can develop after a single episode of ischemia (blood loss) no matter what the cause. But the risk goes up with repeated (multiple) episodes of blood loss. If this proves to be true, then it is essential to predict, recognize, and stop all ischemic episodes.

Some experts suggest that one way to help prevent the damage done to the hip by this problem is to avoid mechanical pressure on the compromised blood vessels. That could mean keeping the child off his or her feet in a nonweight-bearing state. Limited weight-bearing will protect more than the blood vessels. Compression and load on the joint cartilage, growth plate, and bone will also be reduced.

Although these guidelines make sense, how much pressure and force are put on a child’s hips with different activities is not clear. Is running a bigger problem than walking? Is it how often the child is weight-bearing that makes a difference? Or could it be the number of steps taken each day should be limited? And how much does the child’s body weight play a role?

These are just some of the questions that need answers before early and more effective treatment can be prescribed for LCP disease. Many advances in research have been made over the last 100 years. Many more are expected in the next 100!

Evidence for the Treatment of Legg-Calvé-Perthes Disease

Over 100 years have passed now since Drs. Legg, Calvé, and Perthes first described a hip condition in children now referred to as Legg-Calvé-Perthes (LCP) disease. In those 10 decades, three things have become much clearer: what causes the problem, who is affected, and which treatment approaches work best.

In this condition, the blood supply to the growth center of the hip (the capital femoral epiphysis) is disturbed, causing the bone in this area to die. The blood supply eventually returns, and the bone heals.

How the bone heals determines what problems the condition will cause in later life. Perthes disease may affect both hips. In fact, 10 to 12 percent of the time the condition is bilateral (meaning that it affects both hips). This condition can lead to serious problems in the hip joint later in life.

Clearly the problem is one of blood loss called ischemia. The area affected most is the head of the femur (thigh bone). This has been confirmed with today’s modern imaging studies. As a result of this blood loss, the bone dies and starts to collapse. Soon the smooth, round head of the femur starts to flatten and deform.

X-rays helped in the early days of discover to rule out tuberculosis as a possible cause of the hip pain, limp, and loss of motion that accompany Legg-Calvé-Perthes (LCP) disease. It was quickly realized that faulty delivery of blood to the hip was the cause of LCP.

But even with today’s modern imaging tools, the exact vascular (blood supply) problem is unknown. Two theories are currently being investigated: arterial infarction and venous congestion. Arterial infarction refers to blockage of the blood vessels bringing oxygenated blood to the hip. Venous congestion describes a condition in which blood reaches the area but doesn’t return quickly to the heart. Instead, blood pools in the area.

X-rays have also made it possible to classify or “stage” the disease based on severity. But agreement is lacking on the best way to classify LCP. Currently, surgeons are working backwards to identify early stages of the condition and find ways to predict outcomes.

By working backwards, we mean they are looking at the medical records and results of treatment for adults who had this condition as a child. Then they take a look back over the years at X-rays, MRIs, and clinical reports. By seeing the end results, reviewing treatment given and early findings, scientists are able to make better plans for early treatment of children today with Legg-Calvé-Perthes disease.

For example, in this study, X-rays and MRIs of the femoral head deformities seen in adults were compared to the same findings reported in childhood. This type of study technique is called end-result radiographic analysis.

Using this method, they developed a more reliable classification system called the lateral pillar classification. The lateral pillar is seen on X-rays as changes on the outside edge of the femoral head. The classification scheme labels changes in four categories (A, B, B/C, and C) to represent severity from A (mild) to C (severe).

Changes along this side of the femoral head seem to be able to predict final outcomes. Comparing imaging results with treatment applied for each category allowed orthopedic surgeons to see that there was no difference in results based on the treatment applied. So for example, no changes were observed in the lateral pillar after bracing, range-of-motion exercises, or even after no treatment.

The older children (over eight years old) who had surgery to correct the problem were the most likely to have better restoration of the lateral pillar deformity as seen later in adulthood. This was true for mild-to-moderately severe femoral head deformities. Severe lateral pillar changed did not respond better to one type of surgery over another.

The authors came to several conclusions based on the results of this comparative study. First, some children can be spared the discomfort of bracing and even the risks of surgery. Who are these children? Can they be identified ahead of time? They are the patients who have mild changes of the lateral pillar diagnosed before age eight.

Second, something more must be done to successfully treat the severe lateral pillar deformities. Surgery doesn’t really seem to help, so why put these children through that step?

And finally, it is suggested that when the exact vascular problem causing Legg-Calvé-Perthes (LCP) is discovered, then perhaps a more effective treatment can be found. There is plenty of room in the future for research around this problem.

Expert Opinion on Hip Impingement in Perthes Disease

In this expert opinion, two pediatric orthopedic surgeons from Children’s Hospital in Boston discuss femoroacetabular impingement caused by Perthes disease. Perthes disease of the hip (also known as Legg-Calvé-Perthes) occurs when there is a loss of blood supply to the growth center at the top of the femoral head. Without enough blood, the bone dies, degenerates, and collapses.

Children with Perthes disease of the hip may recover fully without further hip problems later. But those patients with growth disturbance of the femoral head and altered shape of the normally round femoral head (top of the thigh bone) may end up with femoroacetabular impingement (FAI) (pinching of soft tissue and bone).

The body is capable of limiting this disease and growing new bone. But in the meantime, the weight of the body on the unstable bone can cause the head of the femur to become more oval-shaped.

That’s a problem because the hip socket is designed to hold the round head of the femur. In fact, the fit is specific and quite tight. That’s what’s needed to provide a stable but moveable hip joint. Without the perfect match-up of femoral head and hip socket, the danger of hip dislocation increases with Perthes disease.

And with the change in shape of the femoral head, there is also a risk of impingement . As the femoral head is pressed down, the femoral neck (between the shaft of the thigh bone and the femoral head) is shortened. There can be a rotation of the bone as well. All these features add to the likelihood of an impingement problem.

How do we know when a child with Perthes hip disease is also experiencing hip impingement? Symptoms of groin pain that is worse with activity or prolonged sitting are the first clues. There could be just stiffness and loss of hip motion without pain. The real tip off is the position of the hip when the symptoms are the worst: internal rotation and flexion.

X-rays will help show what’s going on. The radiologist and orthopedic surgeon look for something referred to as acetabular coverage. This is a view of how much of the femoral head is inside the socket (called the acetabulum). With impingement from Perthes, it is common to see overcoverage (shelf of the socket hangs down over too much of the femoral head).

Other deformities can be seen on X-ray and the physicians use several ways to look for these (e.g., Shenton’s line, cross-over sign, acetabular index). Depth of the socket and presence of rotation of the bones are also assessed. In some cases, it may be necessary to order additional imaging studies such as CT scans or MRIs.

The authors of this article emphasize the need to identify all changes and deformities within the hip complex associated with Perthes disease. They say that successful treatment (especially surgery) depends on understanding all the components that contribute to Perthes hip deformities.

What can be done about femoroacetabular impingement in a child with Perthes hip disease? The surgeon must look at both sides of the hip: the femoral head and the acetabulum (socket). It may be necessary to make surgical corrections of both areas.

On the femoral side, the surgeon may change the length or angle of the femoral neck. The misshapen and enlarged head may have to be corrected, a procedure called osteochondroplasty. This requires surgically dislocating the hip. That sounds pretty dramatic but the authors assure us it can be done safely and is quite effective.

While correcting the deformity that causes impingement, the surgeon will also look for any other areas of soft tissue damage. There may be a tear in the labrum that needs attention. The labrum is a rim of cartilage around the hip socket designed to give the socket a little bit more depth and the hip greater stability inside the acetabulum.

The ultimate goal of surgery for femoroacetabular impingement in the Perthes hip is to improve hip joint motion. Reducing pain and improving joint stability are also important. The surgery can become quite complex when there are numerous changes in the hip to be addressed.

The surgeon must also pay attention to alignment of the involved leg. No sense in making all these corrections to the deformities only to create a leg length difference, loss of joint stability, or abnormal arc of motion.

In summary, children with Perthes hip disease can develop a type of hip impingement as they get older. The effects of the disease in changing the shape of the femoral head contribute to this problem. Surgery to correct the impingement is a possible treatment option. Careful assessment of all deformities and damage present in the hip complex can be done best with surgical dislocation.

Sobering Statistics About ATV Accidents in Children

Here are some sobering and disturbing statistics about all-terrain vehicle (ATV) accidents in children. According to records kept at hospitals around the United States, there have been 4483 children hospitalized for ATV accidents in one year alone (2006).

And a review of the records from 1997 to the present time showed that the rate of ATV-related injuries has gone up. Not just a small increase in the number of accidents but a 240 per cent increase. And that is despite all efforts of the government and private organizations to educate and legislate this dangerous activity.

What makes these machines so dangerous? Power, speed and uneven or steep terrain. The first ATV models were seven-horse power. Remember, that means the engine has the pulling power of seven horses hooked up together. Today there are 500 horsepower ATVs available on the market.

Many of the ATV-related injuries are the result of high-energy trauma. The injuries reported aren’t minor scrapes and bruises. Children and teens with those kinds of injuries and other minor trauma probably don’t go to the hospital. So it’s very likely the number of accidents is much higher than reported.

Of those who do get medical treatment, spinal cord injury, fractures, and other musculoskeletal injuries are the most common. In fact, that 240 per cent increase in number of ATV accidents among children less than 18 years old is accompanied by another equally serious statistic. There has been a 476 per cent increase in spinal injury during the same time period (from 1997 to present).

There can be injuries to the internal organs as well. Punctured lungs from rib fractures, multiple organ injury, spinal cord injury, and head injuries have resulted in 120 ATV-related deaths among children in 2005. Older children (16 years old and older) seem to have the most serious accidents. Girls have fewer accidents but more serious injuries.

Along with the increased number and seriousness of ATV-related accidents in children and teens come greater medical costs. According to one study based on pediatric emergency records, half of all ATV injuries in this age group required surgery. Added hospital costs are estimated to be in the millions.

What can be done to prevent these life-changing (and life-threatening) injuries? Awareness of the problem is always the first step. Reports like this one are helpful in pointing out to all of us how significant ATV-related accidents and injuries can be for children.

We need better injury prevention strategies. Children and teens who do not have the strength, body mass, and motor control to handle a 500-horsepower machine should not be driving them. Injuries are more likely in younger, smaller children. They are less able to stop a vehicle roll over. Girls have less strength and often have more ligamentous and joint laxity. These two physical features combined together may have a significant impact on their ability to hold up during a rollover or other ATV accident.

Emotional maturity and judgment are important, too but much more difficult to measure. Older children who might be better able to stop a rollover are also going faster and taking more chances. The recommended age for ATV use is 16 and older. Parents and guardians would be wise to enforce this age restriction.

The use of protective helmets that have been sized specifically for each rider must be enforced. Several studies have shown that many children injured in ATV accidents were not wearing a safety helmet.

In summary, the use of all-terrain vehicles (ATVs) poses a significant health risk to children and teens, especially anyone under the age of 16. Many serious ATV-related injuries are preventable.

Experts in this area agree that if everyone followed the guidelines put out by the American Academy of Orthopaedic Surgery (AAOS) for the use of ATVs, there would be a 70 per cent decrease in the number of injuries. And that comes with a huge cost savings and reduced number of days lost at work and school. More importantly, the lives of the children would be saved.

Are Braces Still Used for Perthes Disease?

What is the current thinking about the use of braces in the treatment of Legg-Calvé-Perthes disease? This was a popular treatment approach 35 years ago. But is it still relevant today? The authors of this article did an extensive search of the published literature on this topic and offer a summary of present opinion.

Legg-Calvé-Perthes (known as Perthes for short) is caused by a loss of blood supply to the epiphysis (growth center) of the hip. Without enough blood to nourish and replenish the bone, necrosis (cell death) occurs.

Deformity of the femoral head (round ball of bone at the top of the thigh bone) occurs. The affected bone starts to break apart (a process called defragmentation) and collapse. The end-result can be a change in the shape from a round femoral head to an oval or ovoid shape.

Instead of a ball in the socket with smooth, circular motion, the patient develops more of a mushroom-shaped hip. The femoral head is no longer encircled fully by the hip socket. Uneven wear on the oval-shaped head eventually leads to degenerative osteoarthritis. In some cases, severe arthritis develops early in adult life.

The goal of treatment is to prevent these complications. But the best way to do this remains unclear. Braces have been used to keep the hip fully in the socket and prevent changes in the shape of the femoral head. The idea in mind was to preserve the round head during the regeneration process. Bracing also limited how much weight the child could put on the hip. Less pressure through the hip was thought to help keep the round head of the femur in a spherical shape.

And, in fact, studies have supported the idea of keeping weight off the hip as necessary for a good result. At first, children were kept off their feet altogether. They did daily hip motion exercises and were able to keep the natural shape needed for hip mobility and flexibility. But staying in bed for a young, normally active child can be difficult and doesn’t seem like a really good idea.

So the use of bracing was introduced. Well, actually the first orthopedic surgeons to study this approach (back in the 1970s) used plaster casts on both hips and legs. The child’s legs were held far apart with a bar between the legs. Later a special “hip hinge” was developed to accomplish the same thing but allow better movement. They could walk with a walker and with limited weight through the hips.

The early results were positive and more studies were done trying all sorts of different casting and bracing ideas. Twenty years later (in the 1990s), several studies were done to review the results of this treatment approach. As it turns out, the results were actually pretty poor. Two-thirds of the children were not helped by the bracing. Analysis of the data showed that bracing should not be used with severe deformities.

New questions came up: are the results of using the casting method better, same, or worse compared with using braces? When should bracing be used? How long should braces be used? How can you know when it’s time to start weaning the child off the supports? What factors make for the best results?

More studies were done. Over time, a clearer picture emerged. They found that treatment should be based on a classification system that divides patients by age and severity of disease. Mild disease (determined by X-rays) in younger children (five years old or younger) doesn’t really need active treatment. Careful observation may be all that’s required.

Right now, the prevailing thought is that treatment is advised when more than half the epiphysis is affected. Bracing may be recommended if the child is six years old or younger. Surgery may be a better option for children who are seven or older and who have severe disease. Most of the studies support the idea that treatment of any kind just doesn’t seem to make a difference for mild-to-moderate disease in younger children.

In summary, the bracing idea has fallen out of favor in the treatment of Perthes hip disease. Bracing just doesn’t seem to change the anatomy or alignment of the hip. There are some children who might benefit but they must be evaluated carefully and selected individually for this type of treatment.

Eligible children are younger and have significant (more than 50 per cent) of the epiphysis affected. They also have chronic inflammation of the synovial fluid in the joint and partial hip dislocation. X-rays show involvement of the lateral pillar (outside portion of the femoral head). Children who meet these criteria may be the best candidates for bracing. Results should be followed closely and discontinuation of bracing if no benefit is observed.

Why Do Growing Rods Used for Scoliosis Break?

Children with severe scoliosis (curvature of the spine) may have surgery to insert a rod along the spine. The rod helps keep the spine straight. It’s actually a growing rod, which means it operates like a telescope and can lengthen as the child grows. The vertebrae are not fused so the rod spans long sections of the spine.

One of the main problems with growing rods is that they fracture (break). To understand more about growing rod fractures and ways to prevent problems, a group of 10 pediatric orthopedic centers put together a growing rod database. They combined all the information they had from 327 children treated with growing rods throughout all 10 centers.

By putting information about each case into a computer database, they could study and analyze the data. In this study, they looked for risk factors for rod breakage. The hope was to find ways to prevent this complication.

The first thing they noticed was the percentage of children who experienced growing rod fractures: 15 per cent. Then by comparing children with breakage against children without rod fractures, they isolated the risk factors. Here’s what they found:

  • Children with scoliosis as a part of other problems (called a syndrome) had the highest rate of fracture. This was much higher than for children with scoliosis as a result of a neuromuscular problem such as cerebral palsy or muscular dystrophy.
  • Children who could stand upright and walk had a higher risk of rod fracture.
  • Children with single rods (only on one side of the spine) rather than dual rods (placed on both sides of the spine) were at greater risk for rod breakage.
  • When dual rods broke, both sides fractured at the same time in 26 per cent of all cases.
  • Titanium rods break less often than stainless steel rods.
  • Thicker rods were less likely to break compared with thinner diameter rods.

    This is actually the first study to examine growing rod breakage. All manner of potential risk factors were considered (e.g., age, sex, weight, use of bracing before or after surgery, level of rod fracture, location and severity of the scoliosis). But the ones with the greatest significance are listed above.

    There was one other risk factor not previously mentioned. Children who had repeat fractures were much more likely to have a single rod in place (13 per cent for single rods as opposed to two per cent for dual rods).

    Fractures didn’t usually occur right away. Some children did have a rod fracture as early as four months after rod insertion. But the more times the rod was lengthened, the greater the risk for breakage.

    Most of the fractures occurred at places along the spine where the rod was connected to the bone. When they took a closer look, they saw that the type of connector made a difference. Rod fractures occurred more often with hooks (as opposed to screws or hooks and screws combined).

    Age, weight, and severity of scoliosis did not appear to be risk factors. Wearing a brace at any time before or after surgery did not provide protection from rod fractures.

    What can be done to prevent this common complication? The authors don’t know yet without further study but they offer some thoughts. It’s possible that replacing rods sooner in the process might help. The downside of that suggestion is the added surgery and increased risk of other complications like infections and blood clots.

    Finding a better way to attach the rods might help. Using thicker, dual titanium rather than single stainless steel rods may be advised. Since metal fatigue may be part of the reason rods break, studies to find a better rod design might be helpful.

    Surgeons are advised to consider making gradual bends in the rod rather than single angles when adjusting the rods to the curves. It might be better if broken rods were replaced rather than repaired. And it may be a good idea to warn families about the risk of complications including rod fracture.

    The authors point out several other areas that were not specifically studied in this database project. One was the child’s compliance with bracing. It’s possible that bracing does provide some protection but we won’t know that unless actual wearing is confirmed and compared with rod fracture rates.

    Not all centers collected the same information. So some things like curve flexibility (or rigidity), curve location, complications, and specific diagnosis were not compared between the group of children with and without rod fractures. But for a start, this database did provide some very helpful information about incidence and risk factors for growing rods used in the treatment of severe scoliosis in children.

  • Surgeon’s Decision for Children with Hip Subluxation

    It’s decision time for the pediatric orthopedic surgeon. The problem? Hip subluxation (partial dislocation) in children with cerebral palsy. Spasticity (increased muscle tone) is common with cerebral palsy and can cause the muscles to pull unevenly on the hip.

    Over time, as the child grows and the muscles remain short and tight, the head of the femur (thigh bone) is forced out of the hip socket. The direction the round head shifts is clear on X-rays (usually posterolateral or back and to the side). But where is the weak point in the hip socket that allowed the femoral head to pop out?

    This question must be answered when planning surgery to reconstruct the hip. If it’s not addressed, then the same problem can happen again after surgery. There could be instability at the top of the socket (superior direction). This superior deficiency could be more toward the front (anterior) or more toward the back (posterior) part of the hip.

    Then again the instability or deficiency could be multidirectional (present in more than one direction). The problem is really more complicated than that. In many cases, normal growth and development of the bones is altered in these children by the change in muscle pull and biodynamics.

    For example, the femur may twist or tilt thus placing the head of the femur in the socket at an angle. Likewise, any change in the shape or orientation of the pelvic bones that form the upper part of the hip socket can have an impact on alignment.

    The surgeon must take both the direction of the hip subluxation and the location of the acetabular (hip socket) deficiency into consideration when planning corrective surgery. How is this type of evaluation done?

    There are three-dimensional CT scans that allow orthopaedic surgeons to see the entire acetabulum (hip socket). The surgeon needs information on direction, depth, and degree of hip dysplasia (shallow socket). The CT scan provides depth and direction but not degree of dysplasia.

    Pelvic X-rays may offer a better view to measure something called the acetabular index. The acetabular index is a measure already in use to look at the angle of the acetabular roof. Combining these two tests together (CT scan and pelvic X-ray) makes it possible to get a three-dimensional view of the angle and curve of the roof (top) of the acetabulum (socket).

    And thanks to the recent research of orthopedic surgeons in Taiwan, the use of this technique has been validated as a reliable way to define acetabular development in all directions. In that study, they compared a group of children with hip subluxation caused by spastic cerebral palsy to a group of children without any medical problems (the control group).

    Using these two groups for comparison, they were able to see that acetabular dysplasia (shallow hip socket) of children with spastic cerebral palsy does affect the whole socket, not just one side or another. But the anterior (front) portion of the socket had the greatest area of deficiency.

    How will surgeons use this information? Using the acetabular index will give surgeons a more accurate measure of all the planes of the acetabulum. Taking this measurement in consideration along with other factors such as child’s age, function, and other deformities will help direct surgical choices when reconstructing the dysplastic hip in children with spastic cerebral palsy.

    Knee Articular Cartilage Repair in Teen Athletes

    Many different techniques have been developed to repair holes in the chondral (cartilage) surface of the knee joint. Studies have been limited to the results of these treatment approaches in adults. In this report, teens between the ages of 14 and 18 years of age are the focus.

    Each of the 35 participants in the study had knee pain from a large (more than one centimeter-squared) defect in the osteochondral layer of the knee joint. “Osteo” refers to bone, whereas “chondral” directs our attention to cartilage. So the osteochondral layer is the cartilage next to the first layer of bone in the knee joint.

    Defects in the osteochondral layer are fairly common in active adolescents. This type of problem usually develops as a result of trauma. Often there has been a direct blow to the knee. But minor trauma and repetitive motion with a shearing force can also contribute to the development of painful knee problems from osteochondral lesions.

    Each patient was treated with a specific approach called autologous chondrocyte implantation or ACI. Autologous tells us the graft was taken from the patient him- or herself. A donor sample of chondrocytes comes from a non-weight-bearing section of the knee.

    The cells are taken to a lab where they are grown into a larger donor patch of articular cartilage cells. This can take anywhere from four to six weeks. When there are enough lab-grown chondrocytes, the patient comes back in for part two of the surgical procedure.

    In this operation, the damaged cartilage is cleaned out and the edges are shaved smooth in preparation for the graft material. The hole is filled in with donor chondrocytes and covered with a special membrane that is stitched in place, sealed, and watertight.

    After a short post-operative period of immobilization (10 days), each patient went to physical therapy for a rehab program. Everyone followed the same program of leg exercises and activities (e.g., swimming, bicycling, rowing). The athletes were not allowed to participate in running or any impact sports.

    Follow-up extended anywhere from one full year up to 10 years after the procedure. The results were measured based on pain, knee motion, and function. Tiny biopsy samples of the graft cartilage were also taken to look at the results at the cellular level (under a microscope).

    A large number of the group (84 per cent) had excellent results regardless of the size of their lesion (large or small). Pain was less and both motion and function were improved. Of particular interest was the condition of the graft site later. Slightly more than half the group (57 per cent) had a patch of fibrous cartilage fill in the defect.

    One-fourth of the group (about 24 per cent) formed the desired hyaline cartilage. A smaller number of patients (19 per cent) formed a mixture of fibers and hyaline cartilage. Only one patient had a failed result requiring additional surgery.

    The authors took a look at some of the other factors to see if any of these affected the final result. For example, they noted that all but one patient had just a single (called isolated osteochondral lesion. But the lesions weren’t all in the same spot of the knees.

    There were some lesions located (14) on the medial side (side closest to the other knee) at the end of the femur (thigh bone where it joins to form the knee). Half that number (7) were located on the back of the patella. And another six were found on the lateral side of the femur (side away from the other knee). Results did not appear to be influenced by the location of the knee either.

    Interestingly enough, results measured by pain, motion, and function weren’t different (or less positive) when the repaired joint surface turned out to be just fibrous cartilage instead of the real thing. In other words, results were just as good when the repair tissue was not identical to normal hyaline cartilage covering the joint.

    The researchers who conducted this study came to two basic conclusions. First, autologous chondrocyte implantation (ACI) works well in adolescents with painful osteochondrocyte lesions. This is true even when the final tissue isn’t true hyaline cartilage.

    And second, these results point to the need to try other types of cartilage repair (e.g., mosaicplasty, microfracture, abrasion techniques) and see how well they work with this age group. It’s not clear if lesions that don’t cause pain should be treated. But previous studies support the surgical treatment of painful defects before further joint degeneration occurs.

    Evaluation and Treatment of Fractures Through Abnormal Bone in Children

    Fractures in children through abnormal bone take on some unusual characteristics. The bone lesion could be a cyst, a tumor, or infection. In all cases, the fracture is influenced by the lesion and vice versa. Surgeons treating children with bone fractures through abnormalities must take into consideration all aspects of both the fracture and the lesion.

    Some problems like fibromas (soft, benign tumor made up of connective tissue) tend to go away on their own. Even if they don’t disappear, they are relatively harmless and don’t have to be removed. Other lesions such as fibrous dysplasia (weak patches of bone with poorly organized cells) are treated differently depending on the child’s age, size of the affected area, and location of the fracture.

    These are just two examples of the types of benign bone lesions linked with bone fractures discussed in this review article from the Department of Orthopaedics and Rehabilitation at Yale University. Once the fracture and other suspicious looking lesion(s) have been seen on X-ray, then other imaging such as CT scans, MRIs, or bone scans may be necessary. CT scans show the details of bone, whereas MRIs are much better for seeing specifics of soft tissues. Bone scans are usually reserved for patients who might have cancer that has spread elsewhere. Less often, a biopsy of the involved tissue is taken and analyzed in a lab.

    Treatment is aimed at both problems either one at a time or both at the same time. How aggressive treatment is depends on several factors. That’s where knowledge of the different types of bone lesions helps assist the surgeon in determining the best approach to management of the condition. Knowing the natural history (what happens over time without treatment) helps guide treatment decisions. Likewise, having some idea of the usual prognosis (final outcomes with and without treatment) is important, too.

    Let’s take a look at some of the benign lesions presented in this article. Besides fibromas and fibrous dysplasia already mentioned, there are also unicameral and aneurysmal bone cysts. Malignant bone tumors such as osteosarcoma, fibrosarcoma, and chondrosarcoma are also possible problems associated with bone fractures but these are not the focus of this article.

    Bone cysts are spaces filled with some type of fluid. Unicameral bone cysts are often close to the growth plate next to a joint. They tend to fill up with synovial (joint) fluid. Aneurysmal bone cysts are more likely to be filled with blood. The cause of bone cysts remains unknown but there are some theories. Sluggish flow and congestion of fluids, trauma, and local disturbances in blood circulation are some of the more likely causes. There is evidence to support each one of these ideas. Molecular and genetic theories exist as well.

    Knowing how bone cysts develop may help with prevention but once they appear, treatment is based more on the natural history and prognosis. Unlike fibromas that often go away without treatment, bone cysts must be removed surgically. Left alone, they will just get bigger and increase the risk of another bone fracture. If the cyst is large enough, it may be necessary to fill in the empty space (after removal) with a bone graft.

    Aneurysmal bone cysts tend to come back after surgical removal. Efforts are being made to find effective ways to kill any unseen cells left behind. Liquid nitrogen, phenol, and argon beam coagulation are three examples of treatments used to prevent recurrence. Only a very wide resection of aneurysmal bone cysts has a zero per cent chance of recurrence. Other methods under investigation include arterial embolization. This is a way of injecting blood clots into the blood vessel to close it down and prevent further bleeding.

    In summary, bone fractures in the presence of bone abnormalities require a different treatment approach than a simple fracture. The surgeon must examine the lesion as closely as possible with imaging and create a plan of care based on the child’s age, type of fracture, type of bone lesion, including the natural history and prognosis for that lesion. Even though these bone abnormalities are considered “benign” (meaning they aren’t cancerous and won’t kill the patient), they can still cause quite a bit of damage and deformity. Therefore they must be handled carefully in order to get the best results.

    “Rule-Breakers” in Scoliosis Treatment

    Adolescent idiopathic scoliosis (AIS) isn’t an easy problem to treat. Just ask any orthopedic surgeon involved in the treatment of children with this condition. The cause of this type of spinal curvature in teens is poorly understood. That’s why it’s called idiopathic (unknown).

    There are many spinal curve types: fixed curves, flexible curves, structural curves, major curves, minor curves, thoracic curves, thoracolumbar curves, double curves, triple curves, and so on. Finding a way to accurately evaluate and successfully treat this condition is a challenge.

    One way to approach the problem is through the use of a classification system. Such a system helps define the location, type, and severity of the spinal curve. The goal is to direct treatment so that children with the same problem get the same treatment. A secondary goal is to guide surgical treatment (when fusion is needed).

    The underlying desire of treatment is to save as much motion and flexibility as possible. The surgeon gives consideration to the need for good alignment, posture, function, and cosmetics (appearance). Sometimes there’s a fine line between correcting the spinal deformity while preserving flexibility.

    The Lenke classification system for adolescent idiopathic scoliosis (AIS) was first developed in 2001. There’s been 10 years of data collected now using this system. This study was conducted to see how well the system is working.

    There are six curve types described by this system. They are based on location (thoracic, lumbar, thoracolumbar), type (main, double, triple), and whether or not the curve is structural (cannot be corrected) or flexible (can be corrected).

    Using this classification system as a guide, surgeons fuse major curves and minor curves that are structural (fixed). But there are times when individual patient factors lead the surgeon to make a different decision. These are the “rule-breakers”. For example, a structural (fixed or permanent) curve that doesn’t get fused or a nonstructural (flexible) curve that does get fused are “rule-breakers.”

    A study like this is important because what’s the point of having a classification system if the guidelines (“rules”) don’t apply to the majority of patients? When too many patients fall outside the established criteria, then treatment varies and the system breaks down.

    After reviewing the records of over 1300 patients, the authors found that 15 per cent of the group did not follow the rules when carrying out surgical treatment. They took a closer look at the patients who were evaluated using the Lenke classification but treated differently than recommended by this system.

    Analysis of the data showed that treatment was more consistent when using the Lenke system (compared with before the system was put into place). Treatment deviated most often when the less common curve types were the focus of treatment. But for the most part, the system did give surgeons a better handle on which curves were structural versus nonstructural and therefore when to fuse the spine.

    Future studies are needed to measure the results of treatment when the Lenke classification system is followed and compare those results to cases where the rules are broken. Another area of research focus might be looking at reasons why surgeons choose to ignore the treatment recommendations based on this classification system and outcomes in those cases as well.

    Are X-rays Really Needed for Children with Heel Pain?

    Many parents are concerned about exposing their children to radiation. Limiting dental and medical X-rays is one way to avoid overexposure to ionizing radiation (the kind of radiation that can do the most harm). But there are times when X-rays can help prevent worse problems. Heel pain and tenderness from Sever disease is one of those times.

    According to this study from the children’s hospital at the University of Tennessee in Memphis, there are enough abnormal findings on X-rays in children diagnosed with Sever disease that films should be routinely ordered.

    Let’s back up a bit and fill you in on the details. First of all, what is Sever disease (also known as Sever syndrome or by its medical term: calcaneal apophysitis)? Sever disease is a painful heel condition that affects growing adolescents between the ages of nine and 14.

    In this condition, the growing part of the heel bone grows faster than the tendon that connects on the back of the heel. This tightens up the tendon and creates tension where it attaches to the heel. Eventually, the tension causes the area to become inflamed and painful. Fortunately, the condition is not serious. It is usually only temporary.

    Heel pain is the main symptom. Squeezing the heel is painful. The back of the heel may appear red and swollen. It will probably be tender to the touch. The heel and foot may feel stiff, especially first thing in the morning. The heel tends to hurt during activity and feel better with rest. The calf muscles and Achilles tendon may also feel tight.

    Youth who play running and jumping sports (especially on hard surfaces) are most prone to this problem. Sever disease or syndrome used to happen mostly in boys. But with more girls playing sports, boys and girls are now affected equally. Both heels hurt in more than half the cases.

    Now back to the original question. Are X-rays really needed to make the diagnosis of Sever syndrome or disease? Actually, no — but X-rays are advised for children with heel pain of unknown cause to rule out other problems like bone cysts, fibromas and other tumors, and fractures that can accompany Severe disease/syndrome.

    In this study, they took a look back at the medical and radiographic records of 134 feet in children with a known diagnosis of Sever disease. They found a five per cent rate of other more serious problems along with Sever disease — and these were problems that required additional treatment.

    Without intervention, there could have been long-term consequences. So that’s why the recommendation was made to continue the standard practice of ordering X-rays for children presenting with heel pain of unknown origin. The one difference is the type of X-rays. Only lateral radiographs (X-rays taken from the side of the foot) are needed. Limiting imaging to one view will reduce both the radiation exposure and the cost.

    As a final note, the authors were unable to identify any particular factors that might help predict who would have just Sever disease versus those children with Sever and something else. Age, side of involvement, sex (male versus female), symptoms, duration or length of symptoms, and physical findings one examination did not reveal anything helpful in that respect.

    In summary, it is possible to diagnose Sever disease or syndrome without X-rays just based on patient history, symptoms, and clinical exam. But to be sure something else more serious isn’t going on, X-rays are required. And in this study, the number of children who did, indeed, have a second more serious problem was enough to say that the routine use of X-rays in any child with heel pain of unknown cause is still advised.

    Growing Pains in Children: Are They Real or Imagined?

    Growing pains in children are nothing new. Physicians back in the 1800s made note of them. But are they real? And if so, what are they really? If you ask the children affected by this condition, you’ll know the pain is very real.

    The more accurate question might be: what is causing these pains? Is it fatigue? Psychological? Or something in the joint, bone, or surrounding soft tissues? Believe it or not, even with all our current technology, we still don’t really know much about the underlying pathologic or biologic cause of what we refer to as “growing pains.”

    Many studies have been done on this problem. It’s estimated that up to half of all children between the ages of three and 14 experience growing pains. The legs are almost always the site of the painful symptoms. But the arms can be involved — just not as often.

    The pain begins most often during the night either keeping the child awake or awakening the child after falling asleep. Afternoon is another common time period when the pains are reported.

    In this current study, orthopedic surgeons and pediatricians identified 30 children with a complaint of growing pains. The children were followed for a full year to get a better idea of the problem and the results of treatment.

    The researchers looked at blood tests and asked about the presence of other symptoms such as fever, joint swelling, limp, or other abnormal symptoms. X-rays were ordered only when the physician judged them to be necessary. Characteristics of pain were also measured and recorded including intensity, frequency, and duration.

    They found that most children experienced pain lasting anywhere from 10 to 30 minutes. The frequency (how often pain occurred) was much more variable. A small number of children (five percent) reported pain every day. Most of the patients either had pain once a week (45 per cent) or once a month (35 per cent). Afternoon and night pain was very common.

    In this group, the location of pain was limited to the lower legs (shins) and thighs. The pain was severe enough to wake the child up and cause crying in 40 per cent of the group. All lab values were normal. Massage and over-the-counter pain medications were enough to relieve symptoms. Some children had to rest and limit their activities before the pain would go away.

    What can we tell from the results of this study? The fact that only leg pain was reported (no arm pain) may suggest overuse and bone fatigue as a possible cause of “growing pain” in some children. A large number of the younger children (who haven’t reached a rapid growth phase yet) experienced leg pain, so the theory that the bones are growing faster than the soft tissues may not be valid.

    Whether there is an emotional or psychologic aspect to growing pains could not be confirmed by the results of this study. Likewise, the theory that some children have a lower pain threshold could not be proven or disproven with this group. Some experts propose that the way the pain comes on suddenly points to a lack of blood circulation but nothing in this study could support or disprove this idea either.

    It was clear that growing pains are real. They are distressing and depressing to both mother and child. Treatment may give the parents something to do but most studies (including this one) show that the pains go away as the child moves into the teen years.

    If anything helps at all, it’s stretching of the muscles of the legs with analgesics (pain relievers) for comfort. A way to predict who will develop growing pains and prevent them has not been determined.

    Latest Science Behind Hereditary Bone Condition

    Every now and then, when you rub your hand along a bone, you may feel some odd dents and bumps. That’s normal. But some people have many bony bumps or protuberances called exostoses or osteochondromas. This could be part of an inherited condition called multiple hereditary exostoses.

    In this article, orthopedic surgeon Kevin B. Jones from Primary Children’s Medical Center at the University of Utah brings us up-to-date on the science of multiple hereditary exostoses. Using colorful diagrams, X-rays, and photographs, we get a clear idea of the type of problems multiple hereditary exostoses can cause.

    When something goes wrong in the gene that controls bone growth, the cells don’t line up in well-ordered stacks like they are supposed to. Instead, they form uneven, irregular outgrowths of bone. These bony outgrowths are usually covered with a cap made of cartilage.

    Most of what we know about the biochemistry, cellular biology, and molecular biology of this condition comes from studies of fruit flies, zebrafish, and mice. Don’t laugh! The genetic structure and miscoding of the involved cells are remarkably similar

    The result of the altered bone growth can be one bone growing longer than another or deformity as one bone curves too much. Some children have growth disturbances that give them an odd appearance (e.g., arms or legs too short compared with the spine). In rare cases, the osteochondromas become malignant. The cancerous bone is slow growing and can be removed so it’s not usually life-threatening.

    How is this condition treated? Sometimes no treatment is required. The bony outgrowths aren’t painful and don’t cause any problems. In some cases, the bone growths are removed.

    The major area of concern is the deformities — not just because they can limit function, but also because of the cosmetic effect on children. Surgery is often needed to correct bone alignment, put a dislocated joint back in place, and manage differences in leg- or arm-length.

    It may be possible to prevent some dislocations by surgically cutting a ligament before the uneven pull has a chance to have its full effect. Exostoses of the spine can put pressure on the spinal cord or spinal nerve roots causing neurologic problems. Once again, by removing these bony overgrowths, the problem is prevented.

    In the future, it may be possible to design medications that could interrupt the extra bone growth. A better understanding of the hereditary links and cellular biology is required before pharmacologic prevention can be developed. Why some bones are affected more often than others is another mystery that needs to be solved in order to prevent deformities and dislocations.

    Teen Athletes Can Recover From Meniscus Tear in the Knee

    Many studies in adults have proven now the importance of the meniscus (cartilage) in the knee. It used to be common to have a torn meniscus just removed surgically. But years of investigation have shown that the end result of that treatment approach is early knee joint arthritis. So now, the damaged meniscus (menisci – plural) is carefully repaired whenever possible.

    But what about young athletes with the same type of (meniscal) injury? What kind of results do they get with arthroscopic meniscal repair? This study from the University of Michigan in Ann Arbor helps answer those questions. They followed 49 cases of knee arthroscopic surgery used to repair knees with either an isolated meniscal tear or a combined meniscal and anterior cruciate ligament (ACL) tear.

    They measured the results using level of knee pain, knee range-of-motion, and physical activity. The surgeons noted any physical limitations. Scores from a specific survey (Tegner and International Knee Documentation Committee or IKDC) designed to measure function were also included.

    The authors also paid attention to results based on patient age at the time of injury and time between injury and surgery. MRIs were used to determine type of injury (isolated meniscus, meniscus plus ACL tear, type and extent of meniscus injury). X-rays showed if the physes (growth plates at the ends of bones) were still open or not as this could be an important factor in the outcomes of treatment.

    A study like this is important because more and more young athletes are injuring their knees. The important role of the meniscus in sharing the joint load and as a shock absorber and knee stabilizer has been well-documented. Having some understanding of the healing rates and long-term results of surgery for this age group will help surgeons advise and counsel young patients. Knowing if bone age makes a difference aids in this process.

    The patients in this study ranged in ages from nine to 17. There were twice as many boys as girls. Growth plates were open at the time of surgery in most (78 per cent) of the group. The number of athletes with open physes was the same in the meniscus tear only group versus the combined meniscus and ACL injury group. After gathering all the data and analyzing it, here are the significant findings:

  • Only two athletes required a reoperation after the initial repair. Both occurred as a result of another injury in athletes with completed bone growth (closed physes).
  • Reoperation did not seem to be linked with any delays in having the first surgery.
  • Most of the athletes were able to get back into competitive play at their preinjury level about six months after surgery. The exception were those who had a retear and patients who also had an ACL tear. These two groups required a longer rehab period before returning to full sports participation.
  • With the exception of the two athletes who reinjured their knees, healing was 100% after two years. Even tears in menisci that wouldn’t normally heal in an adult were restored.

    This study showed the importance of arthroscopic surgical repair of torn menisci in young athletes. Good results were obtained even for cartilage located in areas of little blood supply. The status of growth plates (open versus closed) does not seem to make a difference in results. The surgeons performing this study also note that the arthroscopic technique they used (called inside-out) was a significant factor in the healing response.

  • Improving Correction of Spinal Deformity in Children

    Over the past 50 years, orthopedic surgeons have changed and improved the way spinal deformities are corrected in children. Safer and more effective ways to correct and hold the spine straight have been developed.

    It started with the use of rods placed alongside the spine to correct the curve. Then wires were used. But there was a concern about the wires poking into the spinal cord and causing problems, so hooks were tried next. Hooks provided three-dimensional correction that was better and safer than wires.

    Most recently, screws placed through the pedicle (supporting column of the vertebral bones) have replaced rods, wires, and hooks. Pedicle screws are used in adults as well as children. But there is one safety concern with screws: putting them in the wrong place (misplacement). How often does that happen?

    To find out just how well screws are working, surgeons from the University of Minnesota conducted a systematic literature review. They looked at all the articles published on the subject of spinal correction with screws. There were more than 1000 articles available but only 90 met their criteria for review. Seventeen of those 90 articles were analyzed.

    In the end, they had enough data to evaluate 13,536 pedicle screws placed in 1353 children under the age of 18. In all cases, the diagnosis was adolescent idiopathic scoliosis (AIS). AIS is a curvature of the spine in teens. The cause is unknown. That’s what “idiopathic” means. This type of scoliosis is different from congenital (present at birth) or neuromuscular scoliosis (caused by a condition such as cerebral palsy or muscular dystrophy).

    The looked at two specific outcomes: 1) how much correction was obtained in the spinal curve and 2) accuracy of screw placement.

    Only studies that reported the number of screws that were misplaced or malpositioned were included. Deformity correction was measured using X-rays to calculate the before and after results. Some studies compared one type of fixation to another (e.g., screws versus hooks). Others were comparing accuracy of screw placement with and without computer-aided navigation.

    They found that screws worked much better than hooks in correcting and maintaining the new spinal curves. Five per cent of the 13,536 screws were misplaced. Stated in the positive, there was a 95 per cent accuracy rate. That’s even better than the 91 per cent rate reported in other studies for adults.

    This systematic review of the published literature adds one more benefit or positive advantage of pedicle screws used in children to correct spinal deformities. Besides making it possible to fuse fewer bones, improve appearance, and lower rates of reoperation, pedicle screws are safe and effective in correcting the curve and holding the new spinal alignment. The concern that smaller pedicle size in children (compared with adults) would cause problems just wasn’t supported since the children had better placement rates than adults!

    Changing Fracture Patterns in Children

    Ecclesiastes is often quoted from the Bible saying, “There is nothing new under the sun.” There is still some truth to that idea but in today’s modern world, there are,indeed, a few new things under the sun. One of them is the way children engage in extreme sports at an early age resulting in changing fracture patterns. And those children are much larger in size now than they were 30 years ago.

    In this report, a particular wrist fracture (of the scaphoid bone) is the focus. Changes in the type of wrist fractures orthopedic surgeons are seeing have changed treatment, too. The scaphoid bone is on the thumb side of the hand. It is located at the end of the forearm with just one small bone (the trapezium) between the scaphoid and the base of the thumb.

    The scaphoid is the bone fractured most often in the wrist. It is kidney shaped with three distinct fracture patterns involving the middle of the bone called the waist and the two ends on either side called poles.

    The distal pole (thumb side) and the proximal pole (wrist side) make up the two other segments. The bone isn’t really divided anatomically into three parts — it is just shaped in such a way that makes it easy to categorize fractures based on their location in any of these three locations.

    One of the changes surgeons have noticed is where scaphoid fractures occur. For example, in a study published in 1980, the majority of scaphoid wrist fractures were in the distal pole. That fracture pattern has shifted now to the waist (middle section) of the scaphoid. Fractures of the proximal pole are still fairly limited (both then and now) but a slight rise in number of proximal pole fractures has been noted.

    Treatment of scaphoid fractures has also changed for a couple of reasons. First, proximal fractures (on the forearm side of the scaphoid bone) may require a longer period of time in a cast. Likewise, fractures that aren’t diagnosed right away (called late-presenting fractures) also take longer to heal.

    High-energy trauma from intense sports such as motocross, extreme soccer, skateboarding, and snowboarding may require more than cast immobilization. High-energy injuries are more likely to cause waist and proximal pole scaphoid fractures. There may be other injuries of the nearby soft tissues and bones associated with the scaphoid fracture.

    Surgery with bone grafting and screw or wire fixation may be necessary for the high-energy scaphoid fractures. Sometimes casting is tried but fracture healing doesn’t take place. Late-presenting (chronic) fractures are less likely to heal with casting. Any cases of fracture nonunion or malunion will require follow-up with surgery.

    With younger children involved in these sports, there is always a concern about the effect of the fracture on the physes (growth plate). A fracture through the growth plate could alter the bone growth and result in a shorter wrist/hand on that side. Distal pole fractures are more common when the growth plate is still open.

    The authors also note that their research has been able to uncover factors that affect (increased) time to healing. These include: displacement (separation) of the fracture, location (waist or proximal pole fractures take longer to heal), longer time between injury and treatment, and the presence of osteonecrosis (bone death).

    In summary, scaphoid wrist fractures in children can be a complex problem. The open physes (growth plates), presence of scaphoid cartilage that hasn’t turned to bone yet, and poor blood supply to this area can make treatment challenging.

    Most nondisplaced acute scaphoid fractures in this age group can be treated with cast immobilization. Chronic, late-presenting scaphoid fractures almost always require surgical repair. Children and family members must be advised that the healing process can take longer than the usual six-weeks-in-a-cast that is typical for most other types of fractures. With early diagnosis and proper treatment, treatment results for scaphoid fractures in this age group are favorable.

    Car Safety for Children in Hip Spica Casts

    Picture this: you have a young child who has had hip surgery and is now in a hip spica cast. That’s a cast from the waist down to the toes. Sometimes it is two-legged (goes down both legs). In other cases, it is one-legged and sometimes one and a half-legged (covers one leg down to the toes but only goes down to just above the knee on the other side). Some spica casts are flexed (or bent) in what looks like a semi-seated position (for fractures). Others children are cast in extension (no flexion).

    Now imagine getting that child safely buckled up in a car. How is that possible? The typical child car seat won’t work because the child can’t bend at the hip or knee. You might lay him or her down on the seat and strap the seatbelt across the body or legs but that is not safe. What do other parents do when faced with this dilemma?

    That’s what this study is all about. Parents of 31 children treated at St. Christopher’s Hospital for Children in Philadelphia, Pennsylvania were asked how they transported their children home from the hospital. The children ranged in age from five years up to 13. Most of the children had hip fractures but a few were treated for hip dysplasia (shallow hip socket leading to hip dislocation).

    Before leaving the hospital, each child was evaluated by a physical therapist for travel safety suggestions. The therapist did not recommend the use of a standard car seat for any of the children.

    There is a specially designed car seat available for this type of transport. Some of the children qualified for this seat. Others were advised by the therapist to use an ambulance. The only other choice was a vest type restraint but that could only be used by older children. In all cases, families were faced with the additional expense of either buying the special car seat or restraint or hiring an ambulance.

    How many actually followed the therapist’s recommendation? Less than one-fourth of the group (23 per cent) was safely transported. There were all kinds of methods used — taxis, vans, SUVs, sitting in a parent’s lap, or simply without restraint. Five of the children were placed in their regular car seats as best as possible. Only three families used ambulance transportation.

    In the weeks after discharge from the hospital, half of the children were only in a motor vehicle for doctor’s appointments. One-fourth of the group were transported somewhere every day. The rest traveled about one to two times each week.

    Fortunately, no one was involved in a car accident. Although it’s the law everywhere that children must be properly restrained, only one mother received a ticket for a traffic violation (the child was on her lap).

    This isn’t a problem faced by every parent, but it is still a dilemma for those whose children end up in a spica cast for any reason. What can be done? Insurance companies don’t pay for the added expense of a specially made care seat system designed to hold a child in a hip spica cast.

    Unless a hospital has a loaner program or special funds available, most families choose to “make do” with what they have. When asked why parents didn’t follow the safety recommendations, they said a) cost was too high, b) no insurance coverage, or c) no access to the special car seat.

    The authors did a little checking on costs parents might face in this type of situation. They found that some insurance companies were willing to pay the $500 to 600 cost of a single ambulance ride but would not cover the cost of purchasing (or renting) the special car seat.

    When available (and often they were not), the specialized car seats went for a $250 deposit and $50/month rental fee. Most of the time, the car seats weren’t even available because too many people failed to bring them back. Or brought them back in such poor condition, they could not be salvaged and had to be replaced. The replacement cost was put on the shoulders of the rental agency.

    How can this problem be solved? The answer is not obvious. Pediatric clinics and hospitals can’t afford to give these car seats away. A loaner program would face the same problems rental agencies discovered with the upfront cost purchasing the seats, non returns, and destruction of the property. There is also the additional cost of hiring staff to administer the program and providing storage for the seats.

    In summary, car accidents are the leading cause of death among children in the United States. There are laws in place requiring the use of appropriate safety seats for infants, toddlers, and children. But children in spica hip casts pose a separate problem for which most parents and families are not prepared. Barriers to safe motor vehicle transport are discussed in this article. Solutions to the problem must be carefully considered.

    Sixteen Studies Provide 16 Treatment Recommendations for OCD

    Sixteen studies were deemed acceptable in quality and design to be included in a systematic review of osteochondritis dissecans (OCD) of the knee. The review was conducted by a panel of pediatric orthopedic surgeons from all over the United States.

    Out of these 16 studies comes 16 recommendations called clinical practice guidelines (CPGs) for the treatment of osteochondritis of the knee in children.

    Osteochondritis dissecans (OCD) is a problem in the cartilage of the knee that affects the end of the femur (big bone of the thigh). The problem occurs where the cartilage of the knee attaches to the bone underneath.

    The area of bone just under the cartilage surface is injured, leading to damage to the blood vessels of the bone. Without blood flow, the area of damaged bone actually dies. A joint surface damaged by OCD doesn’t heal naturally.

    Even with surgery, OCD usually leads to future joint problems, including degenerative arthritis and osteoarthritis. That’s why proper treatment (based on evidence of what works and what doesn’t) is so important.

    But as this report shows, what we don’t know about the treatment of OCD far outweighs what we do know. Most of the recommendations made by this group were graded as inconclusive — meaning there’s not enough evidence to say for sure. Based on clinical experience combined with data from the studies collected, the panel was able to agree (consensus) on four recommendations.

    We’ll start with those four consensus recommendations and then fill you in on what the group had to say about future directions in research. The way the authors reported their consensus recommendations was to say, “In the absence of reliable evidence, it is the opinion of the work group that…”

  • Surgery should be offered to children with unstable or displaced osteochondritis dissecans (OCD) lesions that can be salvaged (saved).
  • Likewise, the same treatment recommendation can be made for those patients who have the same condition (unstable or displaced OCD) but who have reached skeletal maturity (bone is no longer growing).
  • For those patients who do receive treatment for OCD but who don’t get better (pain persists), follow-up is recommended. The surgeon should complete a history, physical examination, and order imaging studies (X-rays, MRIs) to see what kind of healing response is present.
  • Physical therapy is advised after surgery for OCD.

    Some of the advice routinely given patients with OCD will probably still be included in patient education — at least until more conclusive evidence is found to support or negate these recommendations. For example, patients are advised to modify their activities and lose weight if they are overweight. The idea behind these guidelines is to help prevent osteoarthritis.

    As to the specific type of cartilage repair to perform for unstable or displaced but still salvageable OCD lesions…well, that’s an area of great debate and controversy. There are many different surgical techniques currently available but no consensus as to which one works best.

    Likewise, when it comes to nonsurgical treatment of OCD, there simply isn’t enough evidence to support one approach over another. Splinting, bracing, electrical stimulation of the bone, and activity restriction may be prescribed but the effectiveness of any of these techniques is unknown. This is true for both those individuals who are still growing (skeletally immature) and those who have reached full bone maturity.

    With so many unknowns and so few really evidence-based clinical practice guidelines, where do we go from here? The authors’ strongest recommendations are for future studies to help clear up some of the confusion.

    First of all, we need studies that use different surgical techniques but measure the same things (outcomes) in the same way over the same period of time (follow-up). There is a need to find reliable predictive factors.

    These are patient characteristics that help predict when treatment will be successful (or fail). These types of predictive values are needed for four groups: patients who are skeletally mature, patients who are skeletally immature, patients treated conservatively (without surgery), and patients who are treated with surgery.

    When you add the fact that there are many different types of cartilage repair procedures and then look at all the ways these various factors can be combined, you see how complex the problem is of finding conclusive evidence. And that doesn’t begin to evaluate post-operative care.

    The authors conclude by suggesting that the best way to continue future research is to conduct multicenter studies. Surgeons at a number of different children’s hospitals should work together to combine patient data to form larger sample sizes. If everyone gathers the same information then it is more likely that reliable results can be obtained.