March 2015

Predicting recurrence after clubfoot treatment

Photo courtesy of Markell Shoe Co.

Photo courtesy of Markell Shoe Co.

In the search for factors that predict recurrence after use of the Ponseti method for successful treatment of idiopathic clubfoot, conclusive evidence is in short supply. However, the one factor that is consistently associated with the risk of recurrence is compliance with brace wear.

By Rachel Y. Goldstein, MD, MPH

Idiopathic clubfoot is a common congenital anomaly, affecting .5 to 2 infants per 1000 live births.1,2 Throughout the 1970s and 1980s, the pervasive thought was that the rigid clubfoot deformity was not amenable to conservative treatment and that large posteromedial release was required.3 Surgical treatment was bolstered by initially promising results.4-10 However, it soon became apparent that extensive surgical releases resulted in stiff, painful, and arthritic feet that considerably impaired quality of life.9-13 Additionally, these patients suffered from multiple postoperative complications, including skin necrosis, infection, deformity recurrence, pain, stiffness, overcorrection, and undercorrection.9,10

In 1963, Ponseti initially presented his technique for manipulation and serial casting in the Journal of Bone and Joint Surgery;14 however, it did not generate much interest among orthopedists at that time. It was not until 1980, when Ponseti’s group reported their long-term results with serial casting,15 that some surgeons began to adopt his technique. This trend was bolstered by the unsatisfactory long-term results associated with surgically treated clubfeet being reported around the same time.9-12 Later, the establishment of support group websites by parents of children with clubfeet treated by Ponseti furthered the popularity of this treatment method.16

While initial clubfoot correction rates with the Ponseti treatment method are greater than 90%, researchers also have reported recurrence rates of nearly 30%.

In a 2003 survey of Pediatric Orthopaedic Society of North America (POSNA) members, 99% of respondents indicated they initially treat clubfoot with serial cast applications, and 65% use the Ponseti technique.17 In the US between 1996 and 2006, the rate of extensive surgery to treat idiopathic clubfoot in patients younger than 12 months decreased substantially, from just over 70% in 1996 to just over 10% in 2006.2

While initial correction rates with the Ponseti method are greater than 90%,18-23 researchers have reported recurrence rates of nearly 30%.20,24,25 Predicting which patients are likely to experience recurrence, and will therefore require more diligent follow-up, is an important area of focus in the treatment of idiopathic clubfoot.

Photo courtesy of MD Orthopaedics.

Photo courtesy of MD Orthopaedics.

Ponseti technique

Ponseti postulated that other conservative techniques fail because attempts to correct the severe supination of the typical clubfoot by forcefully pronating the forefoot causes an increase in the cavus posture and a break in the midfoot.26 This also leads to jamming of the anterior tuberosity of the adducted calcaneus against the undersurface of the head of the talus.26

Ponseti’s technique differs from the previous conservative treatment methods in that the completely supinated foot is abducted under the talus.16,26-29 The talus is secured against rotation in the ankle mortise by applying counter pressure with the thumb against the lateral aspect of the head of the talus. This manipulates the foot without holding the hindfoot fixed, allowing the calcaneus to rotate in relation to the talus.

Serial casting to correct clubfoot deformity begins as soon after birth as possible. The technique involves a choreographed series of manipulations maintained with a long leg plaster cast. 16,27,30 The initial step involves correction of the cavus through elevation of the first ray of the forefoot and supination of the forefoot to recreate a normal appearing arch. Subsequent casts gradually abduct the foot underneath the stabilized talar head. After at least 60° of abduction, the equinus is corrected. If at least 15° of dorsiflexion cannot be achieved with manipulation, a percutaneous heel cord tenotomy is performed.

Once the final correction is obtained, it is maintained with a cast for three weeks. The foot is then held with a foot abduction orthosis (FAO). The FAO is usually worn 23 hours per day for the first three months, followed by nighttime and naptime wear for three to four years,20,27 though some investigators have found it is difficult to get a child to wear the brace after three years.18 Also, to date, no studies have determined how long the FAO actually needs to be worn.

Outcomes

Initial correction rates of idiopathic clubfoot with the Ponseti technique have been reported to be between 90% and 100%.18-23 The Ponseti technique provides excellent early results and may limit the necessity of extensive surgical procedures in young children.31

At two years after initiating the FAO, one midterm analysis found that clubfoot correction was well maintained: 86% of patients required no further treatment, 13% required recasting, and only 1% of patients required extensive surgery.18 In a randomized study of idiopathic clubfeet comparing the Ponseti technique with extensive clubfoot releases, Zwick and colleagues found that at three years the mean score for the Functional Rating System of Laaveg and Ponseti was higher in the Ponseti group.32 They also found that passive dorsiflexion and passive inversion-eversion were greater in the Ponseti group. PODCI (Pediatric Outcomes Data Collection Instrument) scores and radiographic outcome measures were similar for the two groups.

In a long-term study of patients treated with the Ponseti technique, 74% demonstrated good to excellent results at 30-year follow-up.15 In addition, more than half of the feet followed long term did not require any further treatment beyond additional casting and percutaneous Achilles tendon lengthening.15 A different study noted good to excellent results at 25-year follow-up in 78% of patients.33

Photo courtesy of Markell Shoe Co.

Photo courtesy of Markell Shoe Co.

Predicting clubfoot recurrence

As mentioned earlier, while initial correction rates are greater than 90%,18-23 authors have also reported recurrence rates of nearly 30%.20,24,25 Ponseti considered recurrence of the deformity as part of the initial pathology, rather than a sign of undercorrection. He recommended recasting, repeat Achilles tendon lengthening, and, if there was marked supination, tibialis anterior tendon transfer.14 Multiple studies13,20,23,25,34-37 have attempted to determine which clubfeet will respond to manipulation and casting and which will not.18 Numerous potential risk factors for clubfoot recurrence have been studied.

Atypical deformity. In 2005, Morcuende and colleagues described a new subset of clubfoot they termed the “atypical clubfoot.”34 These feet are characterized by a volar crease, a small bean-shaped foot, a shortened big toe, and a stiff foot. The group reported that these atypical clubfeet may be more resistant to manipulation and therefore at increased risk of failing conservative treatment.

In 1987, Bensahel and colleagues reported their results for a single stage posteromedial release in patients with clubfoot resistant to aggressive physical therapy.35 They categorized the feet into idiopathic, neurologic, and “malformative,” which they defined as clubfeet associated with other congenital deformities, such as arthrogryposis. The results varied with etiology, and the researchers reported that idiopathic feet had a “good” outcome 88% of the time but the malformative feet had a “good” outcome only 25% of the time.

Several demographic characteristics, including sex, race and ethnicity, and age at initial visit, also have been postulated to contribute to the risk of recurrence.

Sex. Most studies report a higher prevalence of idiopathic clubfoot deformity in male patients, with male-to-female ratios ranging between 2.5:1 and 6:1.1.1,38,39 And, in a study of nonidiopathic clubfoot, the predilection for male patients was also found across a diverse array of neuromuscular and genetic causes of clubfoot.40 Kruse et al suggested that, given the higher prevalence of clubfoot in male patients, female patients may require a greater number of genes, or more potent genes, to inherit clubfoot.41 They found that affected female patients were 5.5 times more likely than male patients to transmit idiopathic clubfoot to their children and suggested this finding indicates the less commonly affected sex carries a higher genetic load.41

Several studies have reported no significant relationship between sex and risk of clubfoot recurrence.23,25 However, in a 2014 study, Goldstein and colleagues found in a logistic regression analysis that female patients were 5.3 times more likely than male patients to need surgery for clubfoot recuurence.36

Race/ethnicity. There is clear variability in the prevalence of idiopathic clubfoot with respect to race/ethnicity. The prevalence of clubfoot in whites is 1 to 2 per 1000 live births, but there is a lower prevalence in Chinese of .39 per 1000 live births, and a higher prevalence in Pacific Islanders of 6.5 to 7 per 1000 live births.38 However, Dobbs and colleagues, looking at whites versus nonwhites, found no relationship between race and risk of recurrence.25 And, in a 2006 study of clubfoot patients in New Zealand, Haft found the high recurrence rate of 41% found in their study could not be attributed to the high proportion of clubfeet seen in patients of Polynesian descent.42

Age at initial visit. Although Ponseti recommended that manipulation be started as soon as possible after birth,27,30 various recommendations have been made regarding the upper limit of age at treatment initiation. Several authors have reported the Ponseti technique can be effective in treatment of idiopathic clubfoot in patients aged up to 9 years.43-45 And Morcuende et al reported no increased difficulty in obtaining correction of the deformity with the use of the Ponseti technique in children aged up to 2 years.20

Despite these reports, there is some controversy over whether older age at initiation of treatment is associated with an increased risk of deformity recurrence. Lehman and colleagues reported that patients whose treatments were initiated when they were older than 7 months appeared to have an increased probability of poor results.31 Abdelgawad similarly described that initiating treatment in infants older than 6 months was associated with a higher rate of early failure.18 However, multiple authors have described no significant association between age at initial visit and risk of recurrence.20,23,25,36,46

In a 2009 study, Alves and colleagues looked at 102 clubfeet and compared those beginning Ponseti treatment when older than 6 months with those younger than 6 months.46 They found no significant difference between the groups in the number of casts needed to achieve the initial correction, the rate of relapse, the need for posteromedial release, and the need for tibialis anterior tendon transfer during the follow-up period. In both groups, correction was achieved in all patients using the Ponseti method.

Previous treatment. Multiple studies have reported that idiopathic clubfoot deformities previously treated with nonoperative interventions respond well to Ponseti manipulation and casting.20,43,46 Similarly, no association has been found between previous non­operative treatment and risk of recurrence after Ponseti treatment.25,36,47

Parental factors. A 2004 study by Dobbs et al examining risk factors for recurrence found that parental education at the high school level or below carried a tenfold increased risk of clubfoot recurrence after Ponseti treatment.25 However, they found no significant relationship between parental marital status or parental income and risk of relapse.25 Similarly, researchers haven’t found an association between the source of medical insurance and the risk of relapse.25,36

Initial classification. Numerous classification systems have been proposed to predict treatment course and outcomes of clubfoot deformity. Two of the more commonly used classification systems include the Catterall/Pirani system48,49 and the Dimeglio/ Bensahel system.50,51 Both systems identify key components of the deformity and assign a numerical score, and in both systems a higher score indicates more severe deformity. Both classification systems demonstrate excellent interobserver reliability after a short learning curve.52

Catterall’s system initially identified a group of feet in which a “limited posterior release” performed early was sufficient for complete correction of an idiopathic clubfoot, and the authors explained that “assessment of the fixed deformity may define indications for limited and radical releases.”48

Modifications by Pirani altered the classification system. In the system of Catterall/Pirani, the components of posterior crease, empty heel, rigid equinus, curvature of the lateral border, medial crease, and reducibility of the lateral head of the talus are each scored 0, .5, or 1. The first three components are summed to calculate a hindfoot contracture score and the other three components comprise the midfoot contracture score. Later studies found that the Catterall/Pirani score could be used to estimate the number of weekly casts required,53 and that the hindfoot score could be used to predict the need for tenotomy.53,54

Dimeglio described his classification system as allowing a better understanding of the type of feet that require extensive posteromedial release, conventional posteromedial release, or limited posterior release.51 He reported that the classification allows one to predict the impact of functional treatment, follow its progress, and establish the most beneficial surgical treatment.51 In the Dimeglio/ Bensahel scoring system, the components of dorsiflexion, hindfoot varus, midfoot rotation, and forefoot adduction are scored from 0 to 4. The components of posterior crease, medial crease, cavus, and abnormal underlying musculature are scored as present (1) or absent (0). In a comparison of the classification systems of Ponseti and Smoley, Harrold and Walker, and Catterall and Dimeglio, the Dimelgio system had the greatest reliability in clubfoot categorization.55

Multiple studies have attempted to utilize these scoring systems to predict outcomes and risk of recurrence.20,25,36,37,47,53,54 Most of these studies have found the initial severity classification is not related to treatment success, which may be because different feet respond differently to manipulation.20,30 Additionally, these studies have found that no correlation between initial severity and the number of casts needed for correction37 or the need for surgical intervention.47

Number of casts. Several authors have attempted to link the number of casts required for correction with the risk of recurrence after successful Ponseti treatment.20,25,37,42,47,54 While Dobbs found the more severe the initial deformity, the greater the number of casts required for correction,25 Morcuende reported the number of casts required for full correction was not a long-term prognostic factor for recurrence after treatment.20 However, other authors have found a significant difference in the number of casts required for those who eventually required a surgical intervention for clubfoot recurrence compared with those who did not.36,42,47

Brace wear. The one factor the literature consistently and inarguably demonstrates is associated with the risk of recurrence after successful treatment of idiopathic clubfoot is compliance with the FAO.18,20,23-25,36,42,46,47 In a study of risk factors for recurrence, Morcuende and colleagues found that noncompliance with the FAO was associated with a 17 times greater odds of relapse and that FAO noncompliance was the only studied parameter independently associated with recurrence.20 In patients who had completed serial casting, Dobbs found a 31% relapse rate when they were aged 6 months, and determined all of them had been noncompliant with the FAO.25 The risk of recurrence in FAO-noncompliant patients has been reported to be anywhere from six to 183 times that of FAO-compliant patients.20,25,36

Several authors have pointed out that FAO noncompliance may actually be brace intolerance.25,42 Parents not using the FAO in the prescribed manner may reflect a gradual inability to comfortably brace the foot as clubfoot recurrence is taking place. Despite this, currently available clubfoot scoring systems have failed to demonstrate a link between increased severity scores at initiation of FAO use and brace noncompliance.36,42 In studies of FAO compliance, parental education at a high school level or below was the only risk factor associated with FAO noncompliance.25 No significant relationships were noted between FAO noncompliance and source of medical insurance, parental income, parental marital status, family history, or ethnicity.25,42,56

Conclusion

While introduction of the Ponseti method has substantially reduced the number of surgical interventions required for treatment of idiopathic clubfoot, recurrence after successful treatment remains an issue. Numerous studies have explored factors that contribute to recurrence.

Ideally, factors that could identify patients at increased risk for recurrence at presentation would be beneficial in counseling parents about the expected course of treatment. However, at this time, FAO noncompliance or intolerance is the only reliable indicator of increased risk for recurrence. Parents need to be counseled about the importance of continuing with prescribed brace wear.

Rachel Y. Goldstein, MD, MPH, is an assistant professor of pediatric orthopaedics at Children’s Hospital Los Angeles in California.

REFERENCES
  1. Wynne-Davies R. Genetic and environmental factors in the etiology of talipes equinovarus. Clin Orthop Relat Res 1972;84:9-13.
  2. Zionts LE, Zhao G, Hitchcock K, et al. Has the rate of extensive surgery to treat idiopathic clubfoot declined in the United States? J Bone Joint Surg Am 2010;92(4):882-889.
  3. Main BJ, Crider RJ, Polk M, et al. The results of early operation in talipes equino-varus. A preliminary report. J Bone Joint Surgery Br 1977;59(3):337-341.
  4. Simons GW. The complete subtalar release in clubfeet. Orthop Clin North Am 1987;18(4):667-688.
  5. Simons GW. Complete subtalar release in club feet. Part II–Comparison with less extensive procedures. J Bone Joint Surg Am 1985;67(7):1056-1065.
  6. Simons GW. Complete subtalar release in club feet. Part 1–A preliminary report. J Bone Joint Surg Am 1985;67(7):1044-1055.
  7. Turco VJ. Resistant congenital club foot–one-stage posteromedial release with internal fixation. A follow-up report of a fifteen-year experience. J Bone Joint Surg Am 1979;61(6A):805-814.
  8. Turco VJ. Surgical correction of the resistant club foot. One-stage posteromedial release with internal fixation: a preliminary report. J Bone Joint Surg Am 1971;53(3):477-497.
  9. Atar D, Lehman WB, Grant AD. Complications in clubfoot surgery. Orthop Rev 1991;20(3):233-239.
  10. Lau JH, Meyer LC, Lau HC. Results of surgical treatment of talipes equinovarus congenita. Clin Orthop Relat Res 1989;(248):219-226.
  11. Aronson J, Puskarich CL. Deformity and disability from treated clubfoot. J Pediatr Orthop 1990;10(1):109-119.
  12. Green AD, Lloyd-Roberts GC. The results of early posterior release in resistant club feet. A long-term review. J Bone Joint Surg Br 1985;67(4):588-593.
  13. 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.
  14. Ponseti IV, Smoley EN. Congenital club foot: the results of treatment. J Bone Joint Surg Am 1963;45(2):261-275.
  15. Laaveg SJ, Ponseti IV. Long-term results of treatment of congenital club foot. J Bone Joint Surg Am 1980;62(1):23-31.
  16. Staheli L. Clubfoot: Ponseti management. http://www.global-help.org/publications/books/help_cfponseti.pdf. Accessed March 2, 2015.
  17. Heilig MR, Matern RV, Rosenzweig SD, Bennett JT. Current management of idiopathic clubfoot questionnaire: a multicentric study. J Pediatr Orthop 2003;23(6):780-787.
  18. Abdelgawad AA, Lehman WB, van Bosse HJ, et al. Treatment of idiopathic clubfoot using the Ponseti method: minimum 2-year follow-up. J Pediatr Orthop Part B 2007;16(2):98-105.
  19. Herzenberg JE, Radler C, Bor N. Ponseti versus traditional methods of casting for idiopathic clubfoot. J Pediatr Orthop 2002;22(4):517-521.
  20. Morcuende JA, Dolan LA, Dietz FR, Ponseti IV. Radical reduction in the rate of extensive corrective surgery for clubfoot using the Ponseti method. Pediatrics 2004;113(2):376-380.
  21. Tindall AJ, Steinlechner CW, Lavy CB, et al. Results of manipulation of idiopathic clubfoot deformity in Malawi by orthopaedic clinical officers using the Ponseti method: a realistic alternative for the developing world? J Pediatr Orthop 2005;25(5):627-629.
  22. Colburn M, Williams M. Evaluation of the treatment of idiopathic clubfoot by using the Ponseti method. J Foot Ankle Surg 2003;42(5):259-267.
  23. Willis RB, Al-Hunaishel M, Guerra L, Kontio K. What proportion of patients need extensive surgery after failure of the Ponseti technique for clubfoot? Clin Orthop Relat Res 2009;467(5):1294-1297.
  24. Thacker MM, Scher DM, Sala DA, et al. Use of the foot abduction orthosis following Ponseti casts: is it essential? J Pediatr Orthop 2005;25(2):225-228.
  25. Dobbs MB, Rudzki JR, Purcell DB, et al. Factors predictive of outcome after use of the Ponseti method for the treatment of idiopathic clubfeet. J Bone Joint Surg Am 2004;86(1):22-27.
  26. Ponseti IV. Common errors in the treatment of congenital clubfoot. Int Orthop 1997;21(2):137-141.
  27. Ponseti IV. Treatment of congenital club foot. J Bone Joint Surg Am 1992;74(3):448-454.
  28. Pirani S, Zeznik L, Hodges D. Magnetic resonance imaging study of the congenital clubfoot treated with the Ponseti method. J Pediatr Orthop 2001;21(6):719-726.
  29. Kuhns LR, Koujok K, Hall JM, Craig C. Ultrasound of the navicular during the simulated Ponseti maneuver. J Pediatr Orthop 2003;23(2):243-245.
  30. Ponseti IV. Congenital Clubfoot: Fundamentals of Treatment. New York: Oxford University Press; 1996.
  31. Lehman WB, Mohaideen A, Madan S, et al. A method for the early evaluation of the Ponseti (Iowa) technique for the treatment of idiopathic clubfoot. J Pediatr Orthop Part B. 2003;12(2):133-140.
  32. Zwick EB, Kraus T, Maizen C, et al. Comparison of Ponseti versus surgical treatment for idiopathic clubfoot: a short-term preliminary report. Clin Orthop Relat Res 2009;467(10):2668-2676.
  33. Ippolito E, Farsetti P, Caterini R, Tudisco C. Long-term comparative results in patients with congenital clubfoot treated with two different protocols. J Bone Joint Surg Am 2003;85(7):1286-1294.
  34. Morcuende JA, Dobbs M, Zhivhov M, et al. Identification and treatment of atypical cases of congenital idiopathic clubfoot. Presented at 4th International Clubfoot Congress, IFPOS; Istanbul, Turkey, September 2005.
  35. Bensahel H, Csukonyi Z, Desgrippes Y, Chaumien JP. Surgery in residual clubfoot: one-stage medioposterior release “a la carte”. J Pediatr Orthop 1987;7(2):145-148.
  36. Goldstein RY, Seehausen DA, Chu A, et al. Predicting the need for surgical intervention in patients with idiopathic clubfoot. J Pediatr Orthop 2014 Jul 29. [Epub ahead of print]
  37. Chu A, Labar AS, Sala DA, et al. Clubfoot classification: correlation with Ponseti cast treatment. J Pediatr Orthop 2010;30(7):695-699.
  38. Lochmiller C, Johnston D, Scott A, et al. Genetic epidemiology study of idiopathic talipes equinovarus. Am J Med Genet 1998;79(2):90-96.
  39. Byron-Scott R, Sharpe P, Hasler C, et al. A South Australian population-based study of congenital talipes equinovarus. Paediatr Perinat Epidemiol 2005;19(3):227-237.
  40. Gurnett CA, Boehm S, Connolly A, et al. Impact of congenital talipes equinovarus etiology on treatment outcomes. Dev Med Child Neurol 2008;50(7):498-502.
  41. Kruse LM, Dobbs MB, Gurnett CA. Polygenic threshold model with sex dimorphism in clubfoot inheritance: the Carter effect. J Bone Joint Surg Am 2008;90(12):2688-2694.
  42. Haft GF, Walker CG, Crawford HA. Early clubfoot recurrence after use of the Ponseti method in a New Zealand population. J Bone Joint Surg Am 2007;89(3):487-493.
  43. Bor N, Herzenberg JE, Frick SL. Ponseti management of clubfoot in older infants. Clin Orthop Relat Res 2006;(444):224-228.
  44. Lourenco AF, Morcuende JA. Correction of neglected idiopathic club foot by the Ponseti method. J Bone Joint Surg Br 2007;89(3):378-381.
  45. Goksan SB, Bursali A, Bilgili F, et al. Ponseti technique for the correction of idiopathic clubfeet presenting up to 1 year of age. A preliminary study in children with untreated or complex deformities. Arch Orthop Trauma Surg 2006;126(1):15-21.
  46. Alves C, Escalda C, Fernandes P, et al. Ponseti method: does age at the beginning of treatment make a difference? Clin Orthop Relat Res 2009;467(5):1271-1277.
  47. Bor N, Coplan JA, Herzenberg JE. Ponseti treatment for idiopathic clubfoot: minimum 5-year followup. Clin Orthop Relat Res 2009;467(5):1263-1270.
  48. Catterall A. A method of assessment of the clubfoot deformity. Clin Orthop Relat Res 1991(264):48-53.
  49. Pirani S, Outerbridge H, Moran M, Sawatsky B. A method of evaluating the virgin clubfoot with substantial inter-observer reliability. Presented at Pediatric Orthopaedic Societyof North America Annual Meeting; Miami, FL, May 1995.
  50. Bensahel H, Dimeglio A, Souchet P. Final evaluation of clubfoot. J Pediatr Orthop Part B 1995;4(2):137-141.
  51. Dimeglio A, Bensahel H, Souchet P, et al. Classification of clubfoot. J Pediatr Orthop Part B 1995;4(2):129-136.
  52. Flynn JM, Donohoe M, Mackenzie WG. An independent assessment of two clubfoot-classification systems. J Pediatr Orthop 1998;18(3):323-327.
  53. Dyer PJ, Davis N. The role of the Pirani scoring system in the management of club foot by the Ponseti method. J Bone Joint Surg Br 2006;88(8):1082-1084.
  54. Scher DM, Feldman DS, van Bosse HJ, et al. Predicting the need for tenotomy in the Ponseti method for correction of clubfeet. J Pediatr Orthop 2004;24(4):349-352.
  55. Wainwright AM, Auld T, Benson MK, Theologis TN. The classification of congenital talipes equinovarus. J Bone Joint Surg Br 2002;84(7):1020-1024.
  56. Goldstein RY, Kim S, Chu A, et al. Insurance status as a predictor of outcomes in patients undergoing Ponseti treatment for idiopathic clubfeet. Presented at American Academy of Pediatrics National Conference; San Diego, CA, October 2014.
(Visited 1,658 times, 3 visits today)

Leave a Reply

Your email address will not be published. Required fields are marked *

Spam Blocker * Time limit is exhausted. Please reload CAPTCHA.

This site uses Akismet to reduce spam. Learn how your comment data is processed.