A series of 1100 consecutive foot stabilizations for the correction of deformities associated with residual poliomyelitis has been studied with reference to recurrent deformities. In such recurrences, some form of abnormal muscle pull is the etiological factor most frequently encountered. In order to prevent such secondary manifestations, it is essential that the muscle power on the medial and lateral aspects of the ankle joint be perfectly balanced or completely removed after arthrodesis. Because of the difficulty encountered in estimating exact power in individual muscles, the peroneal and anterior and posterior tibial tendons are now transplanted to the mid-line posteriorly or anteriorly, unless the muscles are known to be completely paralyzed. If transplantation is not needed, the tendons can be excised. The only exception to this is in a cavus deformity, secondary to paralysis of the intrinsic muscles of the foot, in which all the long muscles are known to be normal in power. The exact procedure to be used in each instance obviously depends on the 'set-up' in the individual foot.
Among other etiological factors are associated malformations in the remainder of the extremity. Tibial torsion, knock-knee, and an exaggerated bow in the lower third of the leg are the ones usually seen. In the stabilization of any foot, it should be placed in correct alignment, with the malleoli and the ankle joint without regard to the other deformities. Procedures necessary for the correction of these deformities are then carried out at a later operation in order to establish a satisfactory line of weight-bearing in the extremity as a whole.
Four feet have shown recurrences as a result of stabilizations performed at too early an age. These can easily be prevented by waiting until the child is at least eight years of age. If the patient is younger than this, or if the foot is quite small, the presence of an adequate amount of bone should be proved by roentgenograms prior to operation.
After recurrent deformities have once developed, they are corrected by restabilization of the foot followed by removal or correction of the etiological factor in order to prevent another such recurrence.
(C) 1938 All Rights Reserved.The Journal of Bone and Joint Surgery, Inc.