for Neglected Clubfoot and Residual Deformities Following Treatment

Fig. 35.1

Father and son with clubfoot. The father never had treatment, while his son had an early posteromedial soft tissue release complicated by relapse of equinovarus

All neglected or untreated clubfeet are not the same; while the hindfoot is always rigid, there are varying degrees of rigidity of the midfoot and forefoot deformities. If the forefoot remains relatively flexible (no rigid midfoot cavus), the child will bear weight on the lateral border of the foot with the foot pointing either forward or inward (Fig. 35.2). If there is a rigid midfoot cavus deformity, the foot faces backward with all the weight taken on the dorsum. In this latter case, the prognosis for cast correction alone is not as optimistic as when the foot faces forward (Fig. 35.3). Clubfeet which have been treated by Ponseti method, extensive surgical releases, or other surgeries may have one or more residual deformities of variable stiffness. There may also be a dynamic component to the deformity from muscle imbalance, for example, dynamic supination of the foot during swing phase from overactivity of tibialis anterior.

../images/270913_2_En_35_Chapter/270913_2_En_35_Fig2_HTML.jpg — Fig. 35.2

Some neglected clubfeet point forward or inward during ambulation, suggesting that the midfoot cavus is flexible

../images/270913_2_En_35_Chapter/270913_2_En_35_Fig3_HTML.png — Fig. 35.3

(a) In this patient with a rigid midfoot cavus, the foot points backward. (b) A lack of dorsiflexion may be due to both hindfoot equinus and midfoot cavus

Treatment Principles

Patients living near an organized treatment facility have access to the full complement of treatment options, which should ideally begin with casting using the principles of the Ponseti method. Where there are committed parents with no barriers to transport and clinic attendance, casting can take place for as long as needed. Where there are committed parents but problematic transport logistics, notably due to poverty and rural living locations, hostel or hospital inpatient care should be made available. When organized rehabilitation services are absent or logistically impossible, primary surgical treatment may be a child’s only opportunity for correction.

The Ponseti method, with minor modifications, has shown surprising success in achieving a plantigrade foot in children up to 10 years of age (see Chap. 34). In those cases which fail casting, an “à la carte” approach is used to select the most appropriate surgical procedure based on the residual components of the deformity and their degree of flexibility. Under ideal circumstances, adequate correction can be achieved without intra-articular surgery, reducing the long-term risk of degenerative changes at the ankle and/or midfoot joints. Soft tissue releases (plantar fascia) and extra-articular lengthenings are more desirable than opening joint capsules. In general, children aged 8 and under respond to soft tissue releases and lengthenings with or without a lateral column shortening osteotomy, while those over age 8 with a rigid foot respond best to a combination of soft tissue release/lengthening and osteotomy, a modified Lambrinudi triple arthrodesis, or gradual correction with an external fixator.

Suggested Surgical Algorithm (Table 35.1)

This algorithm is applicable when an organized center is available and will necessarily be modified based on variables related to both the individual and the health system, recognizing that one constellation of treatments will not address every patient’s situation. The treatment begins with serial casting using the principles of Ponseti’s technique and progresses to surgical procedures as needed to address the specifics. Casting is always beneficial, even in feet previously treated by intra-articular releases or other surgical procedures, by reducing the magnitude of surgery required. Casting in walking-age children is more difficult and time-consuming, and a longer casting period is expected, often over several months. Typically little clinical improvement occurs until after the first three or four casts. In older patients the casts are applied each week or two and continue until a plateau in correction occurs.

Table 35.1

Algorithm for treatment of clubfeet in lower resource countries

../images/270913_2_En_35_Chapter/270913_2_En_35_Tab1_HTML.png

FAB foot abduction brace, AFO ankle foot orthosis

There should be a low threshold for extra-articular surgery (Achilles tenotomy, tibialis anterior transfer, plantar fascia release, Z-lengthening of tendons) and osteotomies and a high threshold for intra-articular surgery, capsular releases, or arthrodesis. The extensive intra-articular soft tissue releases (posterior, posteromedial, or posterior-medial-lateral) that were common in the past are rarely required with the range of treatment options now available and our understanding of the condition. However, they can be considered in outreach situations in infants or younger children, such as those seen in a “surgical camp” in a remote location where the logistics of serial casting are not possible and there is only one opportunity to obtain a plantigrade foot. In any child over the age of 2–3 years undergoing general anesthesia for surgical correction of clubfoot deformity, a lateral transfer of the tibialis anterior tendon should be considered to prevent recurrence and eliminate the necessity of wearing a foot abduction orthosis.

Preoperative radiographs may be useful when residual deformities are present and surgical treatment is planned and will ideally be obtained in a weight-bearing position. However, with the goal to evaluate alignment in the setting of maximal correction, we favor stress views rather than attempted weight-bearing images. The foot is held in the maximally corrected position for the AP and lateral x-rays. Abnormalities in alignment and findings such as a flat-top talus or dorsal subluxation of the navicular can be identified.

Persistent loss of dorsiflexion may be due to ankle equinus, midfoot cavus, or both (Fig. 35.3b). Equinus is most commonly addressed with a percutaneous tenotomy using local anesthetic with sedation, ketamine, or general anesthesia. If the acceptable dorsiflexion of 10–20° is not achieved, a return to weekly casting after the tenotomy may facilitate full correction. While the upper age range for complete tenotomy has not been determined, tenotomy has been reported in patients up to 10 years of age. Another option in older children is to perform a three-level percutaneous sliding tendoachilles lengthening. A formal Z-lengthening of the Achilles tendon is also an option. A formal posterior release involving the ankle and subtalar joints may help achieve more dorsiflexion acutely, but ultimately these tissue scar and correction may be lost.

Persistent equinus can result from a flat-top talus. Clinically there is a hard end point or bony block to dorsiflexion, while the tendoachilles does not feel especially tight when palpated with the foot in maximum dorsiflexion. The flattening may be observed on a lateral radiograph taken in maximum dorsiflexion. In such cases soft tissue releases will not provide adequate dorsiflexion. In children one option is to perform an anterior distal tibial hemiepiphysiodesis (“guided growth”) using a staple or small two-hole plate with one screw in the epiphysis and one in the metaphysis. Correction is slow, but for small deformities, this may suffice. In older patients an osteotomy of the distal tibia will be required, creating a new deformity proximally, to address the intra-articular deformity.

An open release of the plantar fascia may be necessary to correct residual midfoot cavus, while a dorsiflexion osteotomy of the medial cuneiform or proximal first metatarsal (if the physis has closed) can be considered when more correction is needed. In severe cases the navicular impinges on the head of the talus when attempting to dorsiflex the foot. Excision of the navicular can be considered although this is rarely required.

Midfoot cavus may also be due to dorsal subluxation of the navicular, often presenting with a triangular appearance, in feet previously treated by extensive soft tissue releases. Options for surgical management include soft tissue release followed by repositioning the navicular and pinning, versus isolated talonavicular fusion after realignment. Remember that fusing the talonavicular joint severely limits subtalar motion and is essentially the same as a triple arthrodesis. In contrast, an isolated calcaneocuboid fusion limits subtalar motion by only about 20%.

Persistent adduction deformity involves a short medial column with relative lengthening of the lateral column and may be treated by release of the abductor hallucis if mild, but more commonly a lateral column shortening is required. Options include excision of the anterior process of the calcaneus (Lichtblau procedure) or the Evans calcaneocuboid wedge resection arthrodesis. The primary author prefers the Lichtblau procedure in children less than 6 years, hoping for a mobile pseudoarthrosis to preserve some joint motion. In children older than 6 years, a calcaneocuboid arthrodesis is preferred, providing adequate correction with less potential for relapse. Cuboid decancellation is not recommended since correction is achieved distal to the deformity and does not correct the obliquity at the calcaneocuboid joint (Fig. 35.4). Another option is a closing wedge osteotomy of the cuboid with placement of the resected bone into an opening wedge osteotomy of the medial cuneiform.