Congenital Talipes Equinovarus: A Reconsideration

J. LEONARD GOLDNER, M.D.


The management of congenital talipes equinovarus continues to be a problem. Much progress has been made during the recent past and many individuals have come to recognize that certain types of "clubfoot" cannot be corrected by nonoperative treatment alone. Every foot that exhibits equinus and varus is not necessarily a true "clubfoot." The basic pathological anatomy of a congenital "clubfoot" is a ligamentous contracture which results in persistent malposition of the tarsal and metatarsal bones. The posterior and medial foot tendons and muscles are shortened. The longer the malposition persists, the more deformed do the pliable cartilaginous tarsal hones become.

Eight Grades

Successful treatment is related to the severity of the foot deformity. The author has classified "clubfeet" into eight different grades, Grade 1 being mild, but requiring operative correction; and Grade VIII being the most severe. All intervening grades require operative treatment for relief of the contracture, and repositioning of the tarsal bones. The classification gradations between I and VIII are usually made in retrospect or during the operation. The amount and kind of surgical treatment necessary to give maximum correction of a particular foot provides the basis for grading. Prior to operation, the experienced examiner can estimate the extent and degree of deformity, but actual observation during the operation is necessary before a detailed description of the involved joints can be given.

Prognosis

Frequently the prognosis for correction can be made at the time of the initial examination. If the forefoot and hindfoot can he corrected almost completely by gentle movement of the foot, and if the tarsal scaphoid and calcaneus actually move, then the prognosis for plaster treatment or even taping is good. If, however, the sinus tarsi cannot he obliterated, if the entire foot cannot be completely rotated externally at the ankle joint, and if the forefoot cannot be corrected passively, then the medial structures, as well as the posterior capsule and tendons, are contracted severely and the prognosis for nonoperative treatment is dismal. Early, careful and complete operative treatment of infant "clubfoot" may well be, in fact, the most conservative treatment.

Case Description

In over a hundred patients observed for at least 15 years, the pattern of treatment has been essentially the same, with variations depending on the severity of the particular foot involved. Identical male twins were recently operated on, one having bilateral clubfeet, and the other having a unilateral clubfoot. Pathology observed in each of the three feet at operation included the following: (1) contracture of the heel-cord triceps surae; (2) contracture of the posterior tibial, flexor hallucis longus, and flexor digitorum longus tendons: (3) contracture of the posterior capsule including the tibiotalar and fibulotalar articulations (the posterior talocalcaneal joint was not opened); (4) contracture of the deltoid ligament, involvement of the anterior tibiotalar ligament because of the forward subluxation of the talus; (5) fixation of the scaphoid to the medial malleolus with contracture of the talonavicular and talocalcaneal ligaments; (6) the anterior tibial tendon was moderately shortened, and (7) the cuboid was displaced medially and the calcaneocuboid joint was moderately distorted. (8) The combination of navicular displacement and medial and posterior ankle and foot contractures was associated with internal rotation of the talus in the ankle mortise and the calcaneus with the talus. The articular surface of the head of the talus was covered medially by the scaphoid and the body of the talus was turned inward as far as the medial border of the talus would allow. A portion of the head of the talus was uncovered laterally. Paradoxically, it appeared to point laterally but actually was pointing medially in relation to the ankle joint. Indentation of the medial malleolus on the body of the talus is readily visualized once the ligaments have been released. When the talus and calcaneus are derotated laterally as a unit, the area of medial compression on the body of the talus due to inversion and internal rotation becomes evident, and when these conditions are corrected a space appears between the talus and the medial articular surface of the medial malleolus.

Operative Procedure

The operative procedure includes: (1) Z-lengthening of the heel cord with release of the medial fibers distally; (2) capsulorrhaphy of the tibiotalar and fibulotalar joints complete; (3) capsulorrhaphy of the deltoid ligament and plantar calcaneonavicular ligament maintaining a small tongue of capsule attached to the tibia; (4) capsulorrhaphy of the talonavicular ligaments: (5) capsulorrhaphy of the anterior tibiotalar ligament from medial to lateral malleolus. (The talocalcaneal ligament and the posterior compartment fo the foot should be avoided.) (6) The talus is then rotated laterally in the ankle mortise and the calcaneus with it. If derotation is not complete and if the scaphoid does not glide readily to the lateral side, a second incision is made laterally, opening the calcaneocuboid joint and the cuboid metatarsal joints. The sinus tarsi is entered and the lateral talonavicular and calcaneonavicular ligaments are released, as are the tibulotalar ligaments laterally. This procedure usually allows full external rotation of the talus and the calcaneus as a unit and reestablishes the lateral border of the foot - the calcaneocuboid angle being changed from convex to neutral. The relationship between the talus and the calcaneus is reestablished and the foot is then lined up with the fibula and medial malleolus. (7) The anterior tibial tendon is detached from the first metatarsal on the medial side and transferred to the dorsum of the first metatarsal where it is reinserted into soft tissue and periosteum in the infant, or into a hole in the first cuneiform in the older patient.

All tendons that have been lengthened are resutured and none is resected. The posterior tibial tendon should be saved and every effort should be made to maintain its original action on the hindfoot. At this point in the operation, excessive correction or the creation of heel valgus is readily possible, particularly in the foot of a child under one year of age. Resuture of a portion of the deltoid ligament and the medial tendons will avoid excessive correction and allow active forces to be applied to the medial border of the foot as the child grows.

The tourniquet is released, the bleeding points are coagulated, and the skin is closed with absorbable suture. In the infant, fixation pins are usually unnecessary to maintain the relationship between the scaphoid and talus but may he required in the older child. Excessive abduction of the forefoot should be avoided and the relationship between the talus and the scaphoid, and the talus and ankle joint, should approach that seen in the physiologic position. If the skin is tight after closure, the foot should be inverted slightly and the tension taken off the skin. Primary healing should be sought. Fluffed gauze and pads are applied, sheet cotton is used and split so that there is no pressure on the skin, and the cast is applied with the foot at right angles and in neutral position in relationship to the malleoli, with the knee at right angles. This cast is changed at 10 to 14 day's so that repositioning can be accomplished if there was tension on the skin initially. At this time the initial internal rotation of the foot and the apparent, but usually nonexistent, tibial torsion have been corrected. In over 90 percent of the clubfeet treated, the internally rotated position has been corrected by derotating the talus in the ankle mortise. In the author's opinion the ligamentous contracture, the position of the talus in the ankle mortise, and the relationship of the adjacent tarsal bones to the talus constitute the primary pathology in congenital talipesequinovarus. If all aspects of the deformity are not corrected, then recurrent clubfoot is the rule.

Operative correction must be made from both the medial and lateral sides of the ankle joint and the midfoot in order to fully' correct the internal rotation of the talus and the medial positioning of the scaphoid, as well as the distortion of the calcaneocuboid joint. Any procedure that attempts to do this without correcting the talus may be successful only because the total deformity was very mild. Severe clubfeet will not be corrected permanently if the ankle joint is not released. Total subtalar release will not be successful in the severe foot and will result eventually in a distorted tibiotalar joint with a foot that is apparently corrected by external rotation but which eventually will either revert to varus or will be placed in a valgus position in overcorrection.

There are definite indications for tarsal/metatarsal release and, if possible, it should be done at the time of the primary' procedure. If this is not possible initially, because of time or other reasons, the major pathology can be corrected by the procedures already described and the tarsal/metatarsal joints can be done at a second stage.

The more severe the clubfoot deformity, the more difficulty may be encountered in obtaining correction. The older the child, the more difficulty occurs in remolding of the ankle joint and the midtarsal joints. During growth spurts, the calf muscle or the medial foot muscles and tendons may become contracted. These contractions will usually respond to a few weeks of plaster stretching.

Roentgenograms taken as the tarsal bones mature show distortion of the body of the talus in the severe foot. This is believed to be due to limb bud malformation, and malposition as the child grows prior to the time that correction is obtained.

A controversy exists as to whether or not the talus is turned inward or outward. Observations from the cases treated at Duke University indicate inward. Also, certain investigators have indicated that the posterior subtalar joint must be released, but this has not been found to be necessary except in arthrogryposis. The risk of avascular necrosis of the talus is great if subtalar release is done.

The basic concepts described in this paper were presented at the General Session of the American Academy of Orthopaedic Surgeons in 1959 or 1960, but the material was not submitted for publication until the patients could be followed to maturity. The material was then written up and published in the Current Practice of Orthopaedics , edited by John Adams and published by C. V. Mosby in 1969. The author recently added more data and illustrations in the preparation of a chapter on clubfoot for Nicholas Giannestras. This work has now been published in the latest edition of The Foot . This summary is presented in the hope that orthopedists who read ICIB may he stimulated to review their management of congenital talipes equinovarus.

Descriptors: Clubfoot: congenital; equinovarus; surgical management: talipes.

Duke University Medical Center, Durham, North Carolina