Long-term research, new genetic and MRI studies advance clubfoot treatment

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Treatment for pediatric clubfoot continues to evolve as researchers cultivate long-term outcomes of conservative and surgical care, identify key genes that may cause idiopathic cases and conduct MRI studies that may individualize management of clubfoot and predict future relapses.

According to Jose A. Morcuende, MD, PhD, an orthopedic surgeon and associate professor at the University of Iowa, many surgeons have reverted to using the noninvasive Ponseti method of casting clubfeet as an initial treatment after studies showed better long-term outcomes with the method compared to soft tissue releases and other extensive surgeries.

“The truth is that treatment of clubfoot is changing, and over the last 10 years, the Ponseti method is becoming the standard of care,” Morcuende, who learned from and worked with Ignacio Ponseti, MD, since Morcuende came to the university as a visiting professor in 1991, said.

However, he noted that some parents of children with clubfoot deformities may prefer that extensive soft tissue releases be performed as an initial treatment, which Morcuende warned may cause stiffness in the foot in the long-term.

Jose A. Morcuende, MD, PhD, of the University of Iowa, said that the Ponseti method has become the standard of care for clubfoot treatment and is as effective for children older than 5 years as it is for younger patients. Image: Jennifer R. Whitmore

“Traditional treatment is to release all the ligaments and tendons around the foot to put the foot straight, but that will result in stiffness and pain in the long-term,” Morcuende told Orthopedics Today. “People still want to perform this type of major procedure, when the tendency now in orthopedics is to do minimally invasive surgeries so you do not get too many scars and better function.”

He noted that studies have proven the long-term efficacy of the Ponseti method and its advantages over initial surgical treatment. In a 50-year follow-up study, Morcuende and colleagues evaluated 61 feet in 31 patients treated with the Ponseti method. After treatment, the patients reported high satisfaction, little or no foot pain and high levels of activity. Morcuende also cited a 30-year follow-up study of 45 patients by Dobbs et al that reported postoperative stiffness, pain and arthritis in the feet of patients treated with a posterior release, plantar fasciotomy or extensive combined posterior, medial and lateral releases.

Steven L. Frick, MD, of Carolinas Medical Center in Charlotte, N.C., added that parents may opt for surgery for their children out of fear that the Ponseti method will be painful or that casting will cause the foot and leg to be smaller.

“Parents need to be educated that it is not painful, and that the casting itself does not seem to contribute to some of the long-term issues of clubfoot,” Frick told Orthopedics Today.

Relapses, subsequent treatment

Wallace Lehman, MD, of New York University’s Hospital for Joint Disease in New York noted that the method is not a silver bullet for the condition.

“A small percentage of kids who fail Ponseti treatment will need surgery,” he told Orthopedics Today. “It is extensive. The release of the foot is a big incision and a big surgery. It is not always successful and sometimes has to be repeated, and the feet do not do as well as with the Ponseti technique.”

No clear reasons exist as to why some clubfoot deformities relapse, according to Morcuende. Frick recommends seeing patients at 6-month intervals for the first 5 years “when the foot is rapidly growing” to monitor for signs of relapse. Repeat casting and Achilles tenotomies or lengthenings are used for relapses in children younger than 3 years old. After age 3 years, anterior tibialis tendon transfers can be performed to treat dynamic supination deformities or supination adduction-deformity of the midfoot and forefoot, Frick said.

“Our difficulty with it is that people say they are using the technique and fail because they are not doing the technique correctly.” — Wallace Lehman, MD

“If we could predict who is going to need a tendon transfer, potentially we could do it earlier and get them out of braces earlier. It would be nice to be able to identify early those patients who will not relapse, and tell children who will not need an anterior tibial tendon transfer that they do not have to wear braces until they are 4 years old,” Frick said. “Right now, we do not have a predictive way of identifying those patients. One risk factor for relapse seems to be weak active everters, but measuring this and correlating it with relapses has been difficult.”

Alice Chu, MD, also of the Hospital for Joint Disease in New York City, told Orthopedics Today that “in our center, 25% to 30% of kids will need a tendon transfer, and that usually comes up between ages 3 and 5 [years].”

Some clubfeet can relapse after 4 years of bracing, Morcuende said. The children in these cases go through a quick growth spurt, in which the heel chord may become tight and develop a small relapse. Dynamic supination is another indication of “excessive pull” of the anterior tibialis tendon, according to Joshua E. Hyman, MD, of Morgan Stanley Children’s Hospital in New York. Other indications of relapse include the presence of a syrinx, Hyman said.

“I have spoken to some of my colleagues across the country and we have seen children who have recurred, received additional casting, as well as an anterior tibialis tendon transfer, and they have gone on to recur,” Hyman told Orthopedics Today. “I have collected a few of these and I imaged their spine, and the majority of them have been found to have either a syrinx or tethered cord. If that is the case, you have to treat the underlying neurological problem. But, you still have a foot that has recurred and sometimes additional casting or additional surgery is all that is needed.”

Patient noncompliance

Patients also may recur after incorrect application of the Ponseti method.

“Our difficulty with it is that people say they are using the technique and fail because they are not doing the technique correctly,” Lehman said. “They are not applying the casting correctly or not doing the percutaneous tenotomy at the proper time. There is a recipe of what to do. If you do not follow the recipe, you are going to lose. Now, we give workshops two, three, four times a year, [to] teach people how to put casts on correctly.”

Patient noncompliance with bracing is another risk factor for relapse, Lehman said. Children may wiggle out of braces during the night or parents may remove the brace. In a study conducted by Abdelgawad et al, Lehman noted that nearly 66% of patients who were noncompliant with bracing had recurrences and nearly 33% required more extensive surgery. When the Ponseti method was accurately applied, according to the researchers, 93% of clubfeet were corrected without recurrence.

To avoid problems of noncompliance with bracing, researchers have invented improved sleeping braces, shoes and dynamic bars.

“There are a number of new brace designs that have come out in the last 5 to 10 years that have replaced the simple patent leather shoes and metal bar with more comfortable sandals specifically measured to fit the foot,” Frick said. “There is also a hinged, dynamic brace that has been developed that makes it harder for children to push their feet out of the shoes.”

Matthew B. Dobbs, MD, of the Washington University School of Medicine noticed many children “had a lot of problems with the static bar in terms of restriction of movement of the legs leading to brace intolerance and blisters on the feet from attempts to escape from the brace,” so he invented a brace with a dynamic bar to allow children to freely move their legs.

“The reason for the design change was to try to increase patient comfort with the sole goal of trying to get parents to be more compliant with the brace,” Dobbs told Orthopedics Today. “The key to preventing relapse is to improve bracing tolerance.”

In a study by Chen et al that examined the efficacy of the Dobbs brace, 7.1% of 28 patients were noncompliant with the brace compared with 41% who used a traditional brace.

Neglected clubfoot

Ponseti treatment for children older than 5 years is as effective as treatment for younger patients, according to Morcuende, Frick, Hyman and Lehman.

“It does take a few more casts and they may require some surgical procedures to help optimally align the foot,” Hyman said. “But, for many of these children, we have been able to avoid the extensive bony operations. Most children born in the U.S. do not have neglected clubfoot by age 5, but we certainly see children who have feet that have recurred and then of course, are slow to be corrected or are not fully corrected. If these children have not had extensive surgery, they can still be successfully treated with the proper application of the Ponseti technique.”

The casting is still in evolution for older children (older than 5 years of age), according to Morcuende, who reports people are using short-leg and long-leg casts to treat these older patients in Brazil and India.

“The other problem is bracing in older cases, and there are studies now underway to evaluate tibialis anterior transfers at the end of casting because they do not need braces and the foot is balanced and done,” Morcuende said.

Genetic causes of clubfoot

Researchers are studying the human genome and MRIs of clubfeet in an effort to identify etiologies for idiopathic cases, create classification systems to identify risk categories of relapse and individualize treatments.

“Figuring out the genes involved could eventually lead to new genetic therapies for clubfoot and potential preventative measures,” Dobbs said.

Christina Gurnett, MD, PhD, a pediatric neurogeneticist at Washington University School of Medicine in St. Louis, MO, who along with her collaborator Matthew B. Dobbs, MD, identified two new gene abnormalities associated with clubfoot — PITX1 and TBX4 — which were found on chromosome 5 and 17.

“Families that have a strong genetic component of clubfoot only make up about 20% to 25% of all kids with clubfoot,” Gurnett told Orthopedics Today. “We are tackling this by trying to understand familial cases and then cases that happen out of the blue.”

“Families that have a strong genetic component of clubfoot only make up about 20% to 25% of all kids with clubfoot.” — Christina Gurnett, MD, PhD

Gurnett and colleagues studied 60 children with a family history of clubfoot. The team discovered chromosomal deletions and duplications that involve PITX1 and TBX4 transcription factors. These transcription factors turn on other genes that are responsible for normal limb development in the first 12 to 15 weeks of gestation. Further studies are required to determine which genes are activated by these factors.

“One thing that clinicians have noted for a while is that the calf is smaller in children with unilateral clubfoot, and it seems to go hand in hand that children with these genetic defects are missing many tissues that should have developed earlier when these transcription factors are acting on the limb bud,” Gurnett said.

Gurnett and her colleagues are studying several families using a genetic technique called exome sequencing, which sequences all 23,000 genes in a single person, to build a research database.

“As a clinical test, you cannot order exome sequencing yet,” she said. “I think this will be available in the next couple of years, but clinicians are going to have a hard time deciphering what it all means until researchers have time to really identify all the genes responsible for clubfoot and other birth defects.”

The environment alone or the environment interacting with genes may also trigger clubfoot, according to Gurnett. Smoking and diabetes are risk factors for the clubfoot and these “environmental factors may play more of a role in genetically susceptible individuals,” she said.

In the future, Gurnett hypothesizes that specific surgical and drug therapies will be geared toward patients with known genetic abnormalities. Certain environmental exposures, vitamins or medications may encourage pathways to develop better, she said. Better surgical or bracing techniques may evolve from knowing how these genetic abnormalities impact muscles in lower limb development.

“Hopefully, we will identify additional new genes in some of our smaller families,” Gurnett said. “We will eventually screen thousands of chemicals to figure out which ones might turn on a specific genetic pathway to improve treatment and prevention strategies.”

MRI studies

Pediatric orthopedist Matthew B. Dobbs, MD, also from the Washington University School of Medicine, is working to translate the genetics findings into improved care for clubfoot by using MRIs to examine limb structure in patients with the genetic mutations Gurnett noted. In his imaging studies, Dobbs found hypoplastic limbs with a loss of muscle bulk in many of the patients, that may help explain why some patients with clubfoot tend to relapse. Once he finds which muscles are deficient, Dobbs says he and other orthopedists can potentially offer individualized treatments such as tendon transfers resulting in improved outcomes.

Another early treatment method Dobbs is exploring is the use of electrical stimulation to improve muscle quantity and quality in those patients who have clinical significant deficiencies.

“The goal of electrical stimulation is to cause the muscle to contract and, as a result, gain strength,” Dobbs said. “This gain in strength may allow patients to maintain better correction and/or minimize the risk of relapse.”

Dobbs hypothesizes that in the future, orthopedists may be able to perform MRIs on clubfoot patients and with that information in combination with knowledge of genetic risk factors be able to predict relapses before they occur.

“For example, if the results of the MRI on a clubfoot patient demonstrates healthy muscle in all compartments of the lower leg, that patient may be at low risk of relapse and treatment could be individualized to allow that patient to stop bracing early,” Dobbs said. “On the other hand, if the MRI demonstrated little or no muscle in the lateral compartment, one may predict this patient has a greater risk of relapse and an early tendon transfer may be more appropriate management.”

Dobbs hopes genetic and MRI research leads to classification systems to apply at the time of diagnosis to predict which patients will relapse and design individualized care.

“We want to give every child the best treatment for him or her,” Dobbs said. “Hopefully, that will be done in the future based on blood and imaging tests.” – by Renee Blisard

References:

• Abdelgawad AA, Lehman WB, van Bosse HJP, Scher DM, et al. Treatment of idiopathic clubfoot using the Ponseti method: minimum 2-year follow-up. J Pediatr Orthop B. 2007; 16(2):98-105.
• Chen RC, Gordon EJ, Luhmann SJ, et al. A new dynamic foot abduction orthosis for clubfoot treatment. J Pediatr Orthop. 2007; 27:522-528.
• Dobbs MB, Nunley R, Schoenecker PL. Long-term follow-up of patients with clubfeet treated with extensive soft-tissue release. J Bone Joint Surg Am. 2006; 88(5):986-996.
• Lovell ME, Oji DE, Dolan LA, Ponseti IV, et al. Health and function of patients with treated idiopathic clubfeet: 50 year follow-up study. Presented at the 2006 Annual Meeting of the Pediatric Orthopedic Society of North America. May 6. San Diego.

• Alice Chu, MD, can be reached at NYU Hospital for Joint Diseases, 301 E. 17th St., New York, NY 10003; 212-598-6261; email: alice.chu@nyumc.org.
• Matthew B. Dobbs, MD, can be reached at the Department of Orthopaedic Surgery, Washington University School of Medicine, One Children’s Place, Ste. 4560, St. Louis, MO 63110; 314-514-3500; email: dobbsm@wudosis.wustl.edu.
• Steven L. Frick, MD, can be reached at the Department of Orthopaedic Surgery, Carolinas Medical Center, 1616 Scott Ave., Charlotte, NC 28203; 704-355-2000; email: steven.frick@carolinashealthcare.org.
• Christina Gurnett, MD, PhD, can be reached at Washington University School of Medicine, 660 S. Euclid, Campus Box 8111, St. Louis, MO 63110; 314-454-4089; email: gurnettc@neuro.wustl.edu.
• Joshua E. Hyman, MD, can be reached at Morgan Stanley Children’s Hospital, Columbia University Medical Center, 3959 Broadway, 165th and 168th, Ste. 800 North, New York, NY 10032; 212-305-5475; email: jh736@mail.cumc.columbia.edu.
• Wallace Lehman, MD, can be reached at NYU Hospital for Joint Diseases, 301 E. 17th St., Ste. 4B, New York, NY 10003; 212-598-6403; email: wallace.lehman@med.nyu.edu.
• Jose A. Morcuende, MD, PhD, can be reached at the Department of Orthopaedic Surgery and Rehabilitation, University of Iowa, 200 Hawkins Dr., Iowa City, Iowa; 319-356-1616; email: jose-morcuende@uiowa.edu.
• Disclosures: Chu, Frick, Gurnett, Hyman, Morcuende and Lehman have no relevant financial disclosures. Dobbs is a paid consultant for and receives royalties from D-Bar Enterprises.

 

How do the results of the Ponseti method compare to the results of surgery?

Ponseti is the ‘gold standard’

Lewis E. Zionts

The often cited goal in the treatment of idiopathic clubfoot is to safely and reliably correct the deformity to achieve a functional, pain-free, plantigrade foot with good mobility, no callosities and allow the patient to wear ordinary shoes. There is no better way to realize these goals than by using the method described by Dr. Ignacio Ponseti in the early 1960s.

Beginning in the early 1970s, extensive surgical release of the joint capsules and elongation of thee tendons had gained widespread popularity to treat clubfoot. While the short-term results were reported as satisfactory, many feet were overcorrected or undercorrected. Even the best outcomes demonstrated some stiffness of the ankle and subtalar joints. These operations were not without complications including infection, wound dehiscence and, on occasion, neurological or vascular problems. Secondary deformities were not infrequent, including dorsal subluxation of the navicular, dorsal bunion and avascular necrosis of the talus. Furthermore, many of these patients required revision surgery to rerelease joints (causing further stiffness), fuse joints or realign the bones. The reported long-term functional outcome of operative release surgery has also been disappointing with the late onset of stiffness, pain, residual deformity and disability. Addressing the operative clubfoot experience, Dr. Dennis Wenger wrote in 1993, “Disassembling a foot, including cutting the ‘spring’ ligament and then pinning it back together again with the hope of predictable foot balance and function proves a daunting task.”

Beginning at the turn of this century, spurred on by the accessibility of the Internet and some very dedicated clubfoot parents, the Ponseti method received a second look. Over the past decade, reports from centers worldwide have reported excellent short-term outcomes using the Ponseti method to treat idiopathic clubfoot. The technique is safe and reliable. The method maintains as much strength and mobility of the foot as possible. Long-term outcome studies have shown excellent results.

The one remaining obstacle left to overcome using the Ponseti approach is the problem of relapse, which may occur in approximately 40% of patients. However, relapses are easily addressed by a short period of manipulation and cast application with resumption of bracing. If repeated recurrences are a problem, Dr. Ponseti recommended an anterior tibial tendon transfer that maintains correction of the foot without violating the joints, thereby maintaining good foot mobility while not affecting the long-term outcome.

In my opinion, the Ponseti method is the gold standard for the treatment of idiopathic clubfoot.

Lewis E. Zionts, MD, is a clinical professor of orthopaedic surgery at Geffen School of Medicine at the University of California in Los Angeles.
Disclosures: Zionts has no relevant financial disclosures.

 

Select cases need surgery

David Scher

There have been several studies published in the last 16 years. The two most critical ones were those out of Iowa by Drs. Coopers and Dietz and, more recently, the one out of Rome by Drs. Ippolito, Farsetti and colleagues, which have both shown outstanding long-term results in adults who had been treated as children with the Ponseti technique. The Ippolito article was the first to compare similar cohorts of patients who had been treated surgically prior to their institution of the Ponseti technique and clearly demonstrated superior results with the Ponseti technique. The major differences between the two are that children treated with the Ponseti technique are much less likely to have arthritis, severe stiffness of the foot and ankle, and overall, are functionally superior to those treated surgically. With this information, we make all efforts to achieve success with the Ponseti technique, thereby avoiding the need for surgery and, in the overwhelming majority of cases, we are able to do so.

There are still select cases where surgery is necessary, and these are typically children who do not have a typical idiopathic clubfoot. These children may have muscle imbalance or may fit under the category of teratologic clubfoot. There are well-respected centers around the country that believe that they are able to achieve successful corrections in every child with every kind of clubfoot regardless of the etiology. However, the research that has been done on teratologic clubfeet and neuromuscular clubfeet, like those in children with spina bifida, does not truly bear that out.

Sometimes after children have been successfully treated with the Ponseti technique, they may develop a recurrence of some deformity, which is successfully treated with minor surgeries such as a tibialis anterior tendon transfer or tendoachilles lengthening. Unlike posteromedial releases performed on infants, these surgeries are not associated with late stiffness or arthritis. We have found, however, that parents can clearly decrease the risk of having a recurrence, and subsequently needing these surgeries, by strict adherence to the bracing protocol.

In general, the overwhelming majority of children born with clubfeet can be successfully treated with the Ponseti technique, without the need for major, open clubfoot surgery.

David Scher, MD, is an associate professor of clinical orthopedic surgery at Weill Cornell Medical College and an associate attending orthopedic surgeon at the Hospital for Special Surgery in New York City.
Disclosure: Scher has no relevant financial disclosures.