The causes of clubfoot deformity are complex, the types of deformity are complicated and diverse, and often coexist with other parts of the deformity, and there are hundreds of surgical treatment methods, and clinical treatment decisions are as varied as the changing world, looking for the true meaning in the changes. Xunzi. In “Persuasion”, it is said: “The wood is straight in the rope, for the wheel, its curve in the rule.” Mencius. Li Lou on the said “: Li Lou’s clear, out of the loss of subtlety, not to the rules, can not become a square circle.” Therefore, to develop rules, grasp the law, must be based on the specific circumstances of the patient and the law of foot deformity changes, the horseshoe foot classification, in order to make treatment decisions and efficacy evaluation.
1, horseshoe foot classification
According to the etiology of the deformity can be divided into: congenital clubfoot; paralytic clubfoot; traumatic clubfoot and spastic clubfoot and other types. This article focuses on the classification and treatment strategies of congenital, paralytic and spastic clubfoot and clubfoot.
(1) Paralytic clubfoot deformity
Horseshoe foot and clubfoot deformity is a common deformity that manifests as: foot drop, mid forefoot inversion, heel inversion, and pronation. Achilles tendon contracture, foot high arch, toe dorsiflexion, metatarsal head weight bearing, can be accompanied by supinated toe foot deformity and so on. Its causes are complex and often coexist with other lower limb deformities. Professor Qin divided the deformity into horseshoe foot deformity and clubfoot deformity, in order to facilitate the formulation of surgical plans and improve the efficacy of treatment.
According to the causes of clubfoot and the main areas where the deformity occurs, they are divided into.
(1) Achilles tendon contracture clubfoot: no obvious deformity changes in the bones and joints of the foot.
(2) Highly arched clubfoot: all combined with contracture of the metatarsal tendon membrane.
(3) Prolapsed metatarsal head horseshoe foot: mainly the first metatarsal head is prolapsed and the metatarsal cuneiform joint is altered in an arch shape.
(4) compound clubfoot: more than two deformities are present and it is the most common type in adults.
(5) Achilles tendon paralysis clubfoot: there is both triceps paralysis and a significant drop foot deformity.
The typing of clubfoot (Qin’s typing): According to the degree of clubfoot, deformity and clinical manifestations as well as the area where the foot is applied, there are 4 types of clubfoot:
(1) Ankle-foot joint relaxed clubfoot: the performance of the Achilles tendon contracture heavy, but the foot of the intertarsal joint is relaxed, when weight-bearing is a horseshoe inversion position, but the foot with the hand to passively turn out its foot inversion deformity can be corrected. It is mainly seen in children and adolescents or those with extensive paralysis of the ankle-foot muscles.
②Horseshoe forefoot inversion: Achilles tendon contracture is heavy, foot inversion deformity is mainly manifested in the forefoot, accompanied by metatarsal tendon membrane contracture, and the heel bone is not fixed inversion. The foot is not fixed inversion of the heel bone. The foot is weight-bearing with the anterior and lateral edges of the foot.
(3) Horseshoe clubfoot: In this type, the posterior tibial muscles are mostly combined with paralysis, the Achilles tendon contracture and foot pronation deformity are light, the part of the foot pronation is in the heel bone, and there is no fixed pronation of the forefoot.
④ horseshoe inversion: the whole foot has inversion, and almost all of the juveniles have foot osteoarthritic deformity changes. However, there are several differences in muscle balance, contracture of the posterior medial soft tissue of the foot, and the type, degree, and characteristics of foot entropion, etc. The milder ones land on the outer edge of the foot. In severe cases, only the dorsum of the foot is used to walk, and a large callus is formed in the dorsal part of the foot.
(2) Congenital clubfoot
Congenital clubfoot can generally be found after birth or gradually appear deformity, with congenital factors. There are different types of congenital clubfoot, but the clinical manifestations after birth have common features. It is characterized by ankle and heel ptosis and pronation, and midfoot and forefoot inversion and valgus. There are many different classifications, including X-ray, pathological and anatomical, with varying degrees of severity and treatment. The lack of a widely used unified classification system to evaluate the severity of preoperative deformity and postoperative outcomes of clubfoot hinders the comparison of treatment outcomes. A number of clinical classification schemes have been proposed, including those of Carroll, Goldern, and Catterall. Recently, two additional classification schemes have been proposed by Pirani et al. and Dimeglio et al. which are based solely on physical examination without requiring radiographs or other special tests. Although these two systems have proven to be reliable, they are not yet accepted. A standardized scoring system for the degree of pre-treatment deformity and post-treatment outcome would help to determine whether a more accurate assessment and comparison of different treatment methods can be made. Currently, there are 3 types of deformities in China based on clinical presentation.
1) Postural clubfoot: The foot is in a horseshoe position but is soft and can be easily corrected to a neutral, dorsal extension or valgus position. The relationship between the bones is normal, and the gap between the inner ankle and the navicular bone can be touched. The heel was obvious, and the calf muscles were normal or slightly atrophied. The dorsal extension and valgus muscles can be actively contracted.
(2) Repeatable clubfoot: the deformity is more obvious and the passive correction cannot be completely corrected to neutral, dorsal extension and valgus position, but it is softer. There is an abnormal change in the relationship of the bones. The protruding talus can be palpated on the back of the foot, the navicular bone is displaced medially but a gap can be palpated between the medial ankle and navicular bone, and the forefoot is in about 56° inversion position at rest. There are skin folds on the dorsolateral side and the heel is obvious. There are no deep skin folds on the sole and posterior part of the foot, and the calf muscles are mildly atrophied.
(3) Stiff clubfoot: The deformity is very obvious, and the forefoot is turned inward at an angle of 90° to the tibia. The talus clearly protrudes from the dorsum of the foot under the skin. The navicular bone is displaced to the medial aspect of the talus head. There is no gap between the deep medial part of the foot and the medial ankle. The dice bones protrude significantly to the lateral side, and the forefoot is in an inversion position. The heel bone was plantar-flexed and turned inward, and the posterior part was hidden upward between the tibiofibula, and the heel appeared to be smaller in appearance, with deeper skin folds on the medial side and sole. The skin of the whole foot is thin and lacks subcutaneous fat. The calf muscles are obviously atrophied.
(3) Spastic clubfoot
The horseshoe foot deformity is classified according to the degree of muscle spasm, random control, antagonist muscle condition, and the presence of fixed deformity. The spasm of the triceps calf muscle can be accompanied by the spasm of other muscles.
(1) Deformity dominated by spasm of the tibialis anterior muscle: it is manifested by inversion of the forefoot and inversion of the heel bone. In the whole cycle of gait, the foot is in a horseshoe position, sometimes with dorsal extension and external rotation, and subcutaneous protrusion of the tibialis anterior tendon. It is often accompanied by bunion and toe deformity, which is a power deformity and muscle spasm.
(2) Deformity with posterior tibial muscle spasm: the deformity is characterized by forefoot inversion, heel inversion, and positive toe tip test. Subcutaneous protrusion of the posterior tibial tendon is seen throughout the cycle of gait, and the foot is in a horseshoe inversion position, which is a power deformity. It is also accompanied by partial knee flexion, positive ankle clonus, and partial scissor gait.
(3) Deformity in which the posterior tibial muscle and the anterior tibial muscle spasm coexist: the tendon protrudes significantly under the skin. Horseshoe clubfoot is often in a state of persistent spasm. The muscle spasm is persistent, forefoot inversion, talus subluxation, heel inversion, bony deformity fixation, are horseshoe deformity, positive ankle clonus.
2.Surgical treatment strategy of horseshoe foot deformity
The purpose of typing is for better treatment, and the design and implementation of a good surgical plan should achieve: no pain in the foot; able to bear weight with the sole; beautiful gait and appearance; able to wear normal shoes; the foot should be flexible; and patient and family satisfaction. The latter is most important.
Surgical treatment strategies for paralytic clubfoot deformity
In the correction of horseshoe foot deformity, the first step is to remove the various factors that cause and affect the development of horseshoe foot deformity, and to choose different surgical approaches according to different types of horseshoe foot. The goal of correction is to completely correct the horseshoe deformity in children and adolescents, and to moderately correct it in young people, adults or those with weaker triceps muscle strength, so that the walking function is not diminished and the ankle-foot joint is not painful after correction of the horseshoe deformity.
Achilles tendon contracture horseshoe foot: correction of Achilles tendon lengthening is performed, but some adult patients have degeneration of the articular surface in front of the talus due to long-term disuse, and after substantial lengthening of the Achilles tendon, the degenerated articular surface turns to the ankle pits to produce pain, and such patients should be controlled within 40° for Achilles tendon lengthening correction of horseshoe deformity, and adults with severe horseshoe deformity should have Lambrinudi triple joint fusion correction.