The Ponseti Method - Clubfoot Treatment

Ponseti Method - The following text is copied from this site: http://www.ponseti.info/ponseti-method.html

"Parents of infants born with clubfeet may be reassured that their baby, if otherwise normal, when treated by expert hands will have normal looking feet with normal function for all practical purposes. The well treated clubfoot is no handicap and is fully compatible with normal, active life." Ignacio Ponseti, M.D.

The majority of clubfeet can be corrected in infancy in about six to eight weeks with the proper gentle manipulations and plaster casts. The treatment is based on a sound understanding of the functional anatomy of the foot and of the biological response of muscles, ligaments and bone to corrective position changes gradually obtained by manipulation and casting.

The results are better if bone and joint surgery can be avoided altogether. Surgery in the clubfoot is invariably followed by scarring, stiffness and muscle weakness which becomes more severe and disabling after adolescence.

The treatment works best when administered within the first few months of life in order to take advantage of the favorable elasticity of the tissues forming the ligaments joint capsules and tendons. With our treatment these structures are stretched with weekly, gentle manipulations. A plaster cast is applied after each weekly session to retain the degree of correction obtained and to soften the ligaments. Thereby, the displaced bones are gradually brought into the correct alignment.

Five to seven plaster casts extending from the toes to the upper thigh with the knees at right angle should be sufficient to correct the clubfoot deformity. Even the very stiff feet require no more than 8 or 9 plaster casts to obtain maximum correction. Before applying the last plaster cast which is to be worn for three weeks, the Achilles tendon is often cut in an office procedure to complete the correction of the foot. By the time the cast is removed the tendon has regenerated to a proper length. After two months of treatment the foot should appear overcorrected. Recently we found that the treatment can be shortened by changing the plaster casts every five days.

Following correction the clubfoot deformity tends to relapse. To prevent relapses, when the last plaster cast is removed a splint must be worn full-time for two to three months and thereafter at night for 3-4 years. The splint consists of a bar (the length of which is the distance between the baby's shoulders) with high top open-toed shoes attached at the ends of the bar in about 70 degrees of external rotation. A strip of plastizote must be glued inside the counter of the shoe above the baby's heel to prevent the shoes from slipping off. The baby may feel uncomfortable at first when trying to alternatively kick the legs. However, the baby soon learns to kick both legs simultaneously and feels comfortable. In children with only one clubfoot, the shoe for the normal foot is fixed on the bar in 40 degrees of external rotation. During the daytime the children wear regular shoes. Shoes attached to the bar often cause pressure blisters and sores. To prevent such distressing problems, we have devised a new foot and ankle abduction orthosis that holds the foot firmly and comfortably in place, causing no sores.

Since the surgeon can feel with his fingers the position of the bones and the degree of correction, X-rays of the feet are not necessary except in complex cases.

When the deformity relapses in spite of proper splinting a simple operation may be needed when the child is over two years of age. The operation consists in transferring the anterior tibial tendon to the third cuneiform.

Poor results of cast and manipulative treatments of clubfeet in many clinics indicate that the attempts at correction have been inadequate because the techniques used are flawed. Without a thorough understanding of the anatomy and kinematics of the normal foot and of the deviation of the bones in the clubfoot, the deformity is difficult to correct. Poorly conducted manipulations and casting will further compound the clubfoot deformity rather than correct it making treatment difficult or impossible.

Surgeons with limited experience in the treatment of clubfoot should not attempt to correct the deformity. They may succeed in correcting mild clubfeet, but the severe cases require experienced hands. Referral to a center with expertise in the non-surgical correction of clubfoot should be sought before considering surgery.

How Does Manipulation and Casting Work?.

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The process that makes the Ponseti Method work with the tendons and ligaments of the foot is described nicely by Zhao et. al:

"Another research suggested that although performing stretching exercises during the maintenance phase is not recommended in the original Ponseti method, it can still reduce the recurrence rate.¹⁵ In fact, the weekly long-leg cast also provides a type of stretch which can gradually correct the deformity and decrease the stiffness of the ankle. Tendons and ligaments exhibit time-dependent behavior which is called creep and stress relaxation. Creep is defined an the time-dependent elongation of a tissue when subjected to a constant load, meanwhile stress relaxation is defined as the time-dependent decrease in load when the tissue is subjected to constant elongation.³⁴ Hence, the manipulative correction in the Ponseti method can be consider as the creep; on the other hand, the cast immobilization and the FAO wearing can be consider as stress relaxation. We all know that although the cast can fully correct the deformity, sufficient time is needed to prevent a relapse.^1,4,8,12 As the FAO is designed to maintain the foot as that by a post-tenotomy cast²⁴, when the foot is placed in the FAO the posterior and medial ankle ligaments and tendons are stretched and thus the stress relaxation begins. As time passes, the contractility of the ligaments and tendons which are involved in the primary deformity and recurrence decreases. Therefore, we can presume that when the contractility of all ligaments and tendons of the ankle reaches static equilibrium the deformity does not recur."

^{Zhao, Dahang & Liu, Jianlin & Zhao, Li & Wu, Zhenkai. (2014). Relapse of Clubfoot after Treatment with the Ponseti Method and the Function of the Foot Abduction Orthosis. Clinics in orthopedic surgery. 6. 245-252. 10.4055/cios.2014.6.3.245.}