Congenital talipes equinovarus deformity (clubfoot), is probably the most common congenital orthopedic condition requiring intensive treatment. It represents a congenital dysplasia of all the musculoskeletal tissues distal to the knee (1). This deformity consists of intraosseous components (within the bones), as well as interosseous components (resulting from abnormal bony relationships). This deformity affects mainly the tarsus, with the tarsal bones, which are mostly made of cartilage, are in the most extreme position of flexion, adduction, and inversion at birth (2).

Nowadays, there is almost universal agreement that the initial management of idiopathic clubfeet should be non-operative, regardless of the severity of the deformity. This entails serial gentle manipulations followed by long-leg cast application at weekly intervals (3-7). Many authors have emphasized on the importance of early management, and it is now settled that the earlier the treatment is begun, the more likely that it would be successful (8-10).

Failure of the conservative management, including the Ponseti method, has been frequently attributed to the non-compliance with the use of the orthosis after correction has been obtained (11-14). This was usually attributed to the long time use of the brace ( ranged 2 to 4 years), psychological problems and fear of some parents from appearance in public with their child wearing the brace, and the thought that it would be a stigma for their children in their future lives. Moreover, the Denis Browne had the disadvantage of holding both feet, this in turn limit the hip and knee movements of the healthy sides well. For all the above mentioned reasons, we have developed a unilateral brace that should hold the affected side only in the desired position after correction, in order to avoid any parents’ discomfort from the voluminous transverse bar, to allow normal free movements of the healthy side, and to allow controlled motion of the affected side as well.

 Kinematics and Biomechanics of the Brace

  According to Ponseti, correction of clubfoot deformity is accomplished by abducting the foot in supination while counter-pressure is applied over the lateral aspect of the head of the talus bone, to prevent rotation of the talus in the ankle. After a achieving full correction with or without percutaneous Achilles tendon tenotomy, the brace is used to maintain the position of correction of the foot. The regular braces depended on the bar connection between both legs to gain the abduction needed for the forefoot.  Foot abduction is required is required to maintain the abduction of the calcaneus and forefoot to prevent recurrence, while the knee joints are left free bilaterally, so that the child would extend his knees (kicking movement). In addition, this movement is crucial for active stretching of the gatrocnemius muscles, and the Achilles tendon. The new brace holds the femoral condyles to control foot abduction, but leaves the anterior and posterior aspects of the knee free to allow for complete range of knee motion in the sagittal plane. That’s how, the brace controls the thigh-foot axis and the lateral rotation of the foot at the desired angle of correction ( about 70 degrees). At the level of the ankle joint, the brace is modified to allow for gradual dorsal extension and plantar flexion as required during successive phases of management. The applied protocol at Aschau Hospital was to restrict any ankle movement (lock the joint), during the first three months (full-time period). Afterwards, active ankle motion was permitted (unlock the joint) through specially designed joints mounted along the mechanical axis of movement of the ankle, medially and laterally. The whole foot was stabilized in abduction, while lateral pressure was applied against the head of the talus (three points of correction). The degree of foot supination was also controllable. Plain X-ray film in the lateral view was done routinely, to assure the position of correction. In contrary to the Denis Browne brace, which was insufficient to hold the heel in place and to prevent it from sliding up and down into the boots, the new brace was perfectly moulded around the foot and allowed no heel displacement during application. This was also confirmed with the lateral X-ray film done.

Fig.1:The new brace; anterior view: note how the brace controls the angle of foot abduction and supination, holds firmly the knee from the sides, allow free knee joint movement, have joints at the level of the ankle joint to allow for controlled ankle motion.

Fig.2 : Lateral view of the brace; note the hinges mounted on the brace on both sides at the ankle joint to allow gradual active controlled foot movement.

Fig.3: Lateral view radiograph  of the foot within the brace, to check the position of the foot, to make sure that the brace fits the foot adequately and to check the position of the hinges in relation to the ankle joint.

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