[Comparison of treatment results of idiopathic and non-idiopathic congenital clubfoot : prospective evaluation of the Ponseti therapy].

BACKGROUND: Clubfoot deformity is one of the most common congenital musculoskeletal deformities and occurs in newborns with different neuromuscular diseases. To date the Ponseti method is the gold standard for the treatment of idiopathic clubfeet but not for non-idiopathic clubfeet which are associated with neuromuscular diseases. The results of the treatment for congenital idiopathic and non-idiopathic clubfeet according to Ponseti performed in our department since 2004 were compared concerning results and relapse surgery with particular reference to the compliance of the parents concerning the use of an abduction splint. PATIENTS AND METHODS: A total of 101 children (28 female and 73 male) with 159 clubfeet were treated with the Ponseti method and included in this prospective non-randomized cohort study. Of these children 27 with 48 affected feet suffered from neuromuscular diseases which are associated with clubfoot deformity, such as myelomeningocele (n=4), arthrogryposis (n=9) and various other syndromes (n=14). The degree of the deformity was evaluated with the Pirani score initially, after casting and at follow-up. Parents were asked at follow-up to state subjectively how compliant they were with the abduction splint treatment. The necessity of surgical treatment of relapses was recorded. Statistical analysis was performed applying χ(2) and Kruskal-Wallis tests for the comparison of idiopathic and non-idiopathic clubfeet.
RESULTS: The average period of follow-up was 36 month (range 6-75 months) and non-idiopathic clubfeet were initially significantly more severely deformed according to the Pirani-score (p=0.013). Treatment of non-idiopathic clubfeet was started significantly later than that of idiopathic clubfeet (p=0.003) and took significantly longer (p <0.001). A correlation between the initiation of casting and the duration of casting was not found (p=0.399). At the end of the casting period no significant differences were found between correction of idiopathic and non-idiopathic clubfeet with respect to the Pirani score (p=0.8). The mean score after casting was 0.1 in both groups. At mid-term follow-up the score increased in both groups but stayed below 0.5 with non-idiopathic clubfeet showing a significantly higher score than idiopathic clubfeet (p=0.014). Relapse surgery was necessary in 11% of the patients. No significant difference in the revision rate was found between the two groups (p=0.331) and peritalar release was not necessary in either group. The rate of revisions correlated with the compliance concerning the use of the abduction splint (p <0.001). Only 61% of the parents stated that they adhered strictly to the abduction splint treatment recommendations with no significant difference between the groups (p=0.398).
CONCLUSION: This study shows good initial results after Ponseti treatment for idiopathic as well as non-idiopathic clubfeet. Based on the good functional results all clubfeet should initially be treated with the Ponseti method regardless of the etiology.