Pediatric orthopedic cases 28

CASE                                                             

Dr. Melinda Sharkey

A 10-day-old male is brought into your office for evaluation of foot deformities. The parents say the foot deformity was noted on prenatal ultrasound but they did not come in for prenatal counseling. The mother’s pregnancy and delivery were uncomplicated. There is no family history of foot deformity. The parents are healthy. The infant is healthy. The babies’ feet appear as follows (Fig. 10–47):

 

 

Figure 10–47 Pictures courtesy of Melinda Sharkey, MD.

 

The deformities are consistent with:

1. Metatarsus adductus

2. Calcaneovalgus

3. Congenital vertical talus

4. Clubfoot

 

Discussion

The correct answer is (D). The photo shows an infant with bilateral clubfoot deformities. Clubfoot deformity can be conceptualized as four separate components including cavus, adductus of the midfoot on the hindfoot, hindfoot varus, and equinus (CAVE). In particular, the adductus and cavus can be appreciated in the photo. Calcaneovalgus is a transient, positional deformity due to in-utero positioning and presents as extreme dorsiflexion and eversion of the foot (opposite of clubfoot). Congenital vertical talus deformity, like clubfoot, is a structural abnormality and presents as a stiff rocker-bottom deformity with abduction and dorsal dislocation of the forefoot on the hindfoot (again opposite of clubfoot, but stiff unlike calcaneovalgus). Metatarsus adductus strictly involves the forefoot and is not associated with cavus or hindfoot abnormalities and is often very flexible.

The Ponseti method of clubfoot treatment is described to the parents. Figure 10–48 is a photograph of the first cast placed on the left foot. The goal of the first cast is to correct:

 

 

 

Figure 10–48

1. Cavus

2. Equinus

3. Adductus

4. Supination

 

Discussion

The correct answer is (A). The Ponseti method requires correction of the midfoot cavus prior to correction of the other parts of the foot deformity. The first ray, which is pronated relative to the hindfoot, is supinated, as shown in the cast, in order to bring the forefoot/first ray in line with the hindfoot and stretch the tight plantar structures of the foot (cavus).

The feet correct with serial casting and heelcord tenotomies. The parents are compliant with long-term bracing. At about 2.5 years of age it is noted that the deformity is starting to recur. This is especially obvious when the patient is walking and the forefoot supinates. The patient is tending to walk on the lateral border of the foot. The table examination shows the foot is totally flexible with adequate dorsiflexion at the ankle and good subtalar joint motion including the ability to position the heel in valgus.

Appropriate treatment at this time includes:

1. Repeat serial casting

2. Physical therapy

3. Anterior tibialis tendon transfer

4. Watchful waiting

 

Discussion

The correct answer is (C). The patient demonstrates dynamic supination with walking in the presence of a foot that remains supple including the subtalar joint evidenced by the observation of heel valgus. Appropriate treatment at this time is anterior tibialis tendon transfer (split transfer or complete transfer) to one of the dorsolateral foot bones (cuneiform or cuboid).

 

Objectives: Did you learn...?

 

Clubfoot deformity can be conceptualized as four component deformities: cavus, adductus, varus, and equinus?

 

Serial casting followed by heelcord tenotomy, as described by Ponseti, is the standard of care for infant clubfoot deformity?

 

Long-term bracing (up to 4 years) is important to prevent recurrence of clubfoot deformities?

 

Roughly ¼ of patients with clubfoot will benefit from an anterior tibialis tendon transfer for dynamic supination with walking?