Foot Problems
Kenneth J. Noonan, MD, MHCDS
VINCENT S. MOSCA, MD
Todd A. Milbrandt, MD1
1Guru:
Clubfoot
While an entire book can be written on clubfoot, we will just stick to a limited number of pitfalls. Clubfoot is frequently part of an underlying syndrome, thus a complete history and physical examination is warranted to uncover other abnormalities. Clubfoot is also associated with tarsal coalition tibia and fibular hemimelia.1 There is no indication for pelvis radiographs, as there is no known association between clubfoot and developmental dysplasia of the hip (DDH).2 Regardless, all children being evaluated for musculoskeletal problems should have a careful hip examination; parents love it when you “check under the hood.” Imaging of hips should be based purely on risk factors or findings suggestive of DDH.
THE GURU SAYS…
When you first meet idiopathic clubfoot babies and their families, there is understandably a significant amount of fear and anxiety about the child’s future function. If you start the conversation with the fact that there is an excellent chance that their child will run, jump, and play with their peers, it helps assuage some of that fear. It is also important to emphasize that if the clubfoot is unilateral they will notice a skinnier calf and widened and shortened foot compared to the other side, but this won’t have any effect on their outcome.
TODD A. MILBRANDT
All clubfeet will benefit from initial treatment with the Ponseti method, a series of manipulations and cast applications, which, when combined with a heel cord tenotomy, provides initial correction of the idiopathic clubfoot in up to 95% of patients.3 Even children with syndromic clubfeet (who have a higher rate of residual deformity) will have some improvement in their deformity. Some practitioners have very good success with the Ponseti method in these feet, and they cite the need to go slow in these stiff feet and the need for many more casts than is usual in idiopathic clubfeet. In our opinion, the main pitfalls in use of the Ponseti method result from deviation from the prescribed technique as described by the originator.4
THE GURU SAYS…
Bottle feeding the child can definitely keep the child more calm, although sometimes the timing does not allow this to occur. Using sucrose water can significantly decrease the pain response during the casting process.6
TODD A. MILBRANDT
THE GURU SAYS…
Plaster casts can be easier to mold the heel and foot, although there are some advantages to removable flexible fiberglass material.
TODD A. MILBRANDT
THE GURU SAYS…
For removal, consider soaking the casts off. This allows the parents to bathe the child, which they like, and it doesn’t create an agitated baby.
TODD A. MILBRANDT
Ponseti Method
Pitfalls in Manipulation
▶ Hyperpronation of the first ray. The foot should be initially supinated. The foot should remain supinated throughout the casting procedure; as increased correction is obtained, the supination naturally decreases to a more normal alignment.
▶ Attempting to place the foot in a dorsiflexed position prior to correcting the hindfoot. This will block the eversion and abduction of the calcaneus underneath the talus, subsequently preventing full correction of the clubfoot. One should maintain the foot in equinus during the sessions of manipulation and casting.
▶ Errantly positioning pressure over the calcaneal cuboid joint.5 This will block the reduction of the calcaneus underneath the talus and prevent subtalar correction. Fulcrum of pressure should be positioned over the head of the talus.
Pitfalls in Casting
▶ Casting children who are agitated. Babies are comforted with bottle-feeding during the casting procedure.6 Low lighting in a private room (rather than in a large cast room) is also soothing.
▶ Failure to use long leg casts. Long leg cast application is always used and is integral to the success of the method. The cast must be applied in two sections. The short leg section is applied and carefully molded around the foot before extending the cast above the knee. Trying to focus simultaneously on the foot mold while keeping the knee in a fixed position risks poor foot pressure application as well as bunching up of the cast padding in the popliteal fossa.
▶ Pressure sores from the manipulation and casting in patients with spina bifida or arthrogryposis (Fig. 29-1)
▶ Placing too much or too little padding around the foot and ankle. Two or three layers of cotton roll are sufficient before application of the plaster cast
▶ Attempting to cast the foot in correction beyond that obtained by manipulation
▶ Pressure in the popliteal fossa from the proximal trim line of the short leg cast when converting to the long leg cast
▶ Overtrimming. When trimming the cast down, don’t expose too much of the dorsal aspect of the foot proximal to the metatarsophalangeal joints, as this will often lead to a tourniquet effect and swelling of the toes
Pitfalls in Heel Cord Tenotomy
▶ Performing tenotomy before the heel is in valgus and foot abduction of greater than 60° is noted. This will block the eversion of the calcaneus in the subtalar joint and lead to midfoot breech and a rocker bottom deformity. If you are a newbie, do these in the OR until comfortable.
▶ Holding the ankle in excessive forced dorsiflexion prior to tenotomy will result in difficulty in palpation of the Achilles tendon.
▶ Injecting large amounts of lidocaine around the tendon will make palpation difficult. We put lidocaine cream on first. Do the procedures and then inject marcaine or lidocaine after tenotomy. Wait 15 minutes before applying the cast.
▶ Performing a tenotomy at the cutaneous heel crease (Fig. 29-2, dashed arrow) can be difficult and potentially detrimental, as you will be too distal and potentially into the substance of the Achilles tendon insertion on the calcaneus. Tenotomy needs to be approximately 1 centimeter proximal to the distal heel crease (Fig. 29-2, solid arrow).
▶ Incomplete tenotomy should be suspected when there is no palpable “pop” and an immediate increase in dorsiflexion of approximately 15° to 30°. The tendon should be revisited with the knife to complete the transection.
▶ Transection of local venous structures, and possibly the peroneal artery, has been noted.7 When excessive bleeding occurs, simple pressure on the heel cord for an additional 3 to 4 minutes before placing in a long leg cast is usually all that is necessary.
Pitfalls in Abduction Bracing
▶ Noncompliant use of the abduction orthosis.3,8 Successful use of an orthosis is associated with prevention of deformity recurrence.
▶ Errors in fitting of the abduction orthosis include deviation from the shoulder width positioning of the shoes and standard external rotation of the feet of 50° to 70°.
▶ Pressure sores can result from poor fit of the shoes. For the first week the skin should be checked at each diaper change to detect and treat potential blisters or other pressure phenomena.
Some clubfeet can develop a “complex clubfoot” pattern during the Ponseti method. When wondering if the foot you’re treating is developing this pattern, think reflex sympathetic dystrophy. Besides retraction of the great toe and full plantar crease as described by Ponseti; if the foot is red, very swollen, and the child absolutely hates to have the foot touched (reflex sympathetic dystrophy-like symptoms) you are likely dealing with a complex
clubfoot pattern (Fig. 29-3). In these cases, the best thing to do is to stop treatment. Give the child a few weeks’ break and start again; albeit more slowly. ORTHOPAEDICS 101: Don’t apply the cast beyond the degree obtained with manipulation.
clubfoot pattern (Fig. 29-3). In these cases, the best thing to do is to stop treatment. Give the child a few weeks’ break and start again; albeit more slowly. ORTHOPAEDICS 101: Don’t apply the cast beyond the degree obtained with manipulation.
With the Ponseti method, over 98% of clubfeet will have good initial correction and will not need extensive posterior medial release. Over time, recurrent or residual deformity in clubfeet can be present in up to a third of patients. Repeat serial casting should be performed for these feet. If full deformity correction cannot be obtained, an ala carte approach to surgical correction is taken in these feet. For instance, posterior contracture can be managed with a repeat tenotomy, open Achilles lengthening, or even posterior release of the ankle joint. Dynamic forefoot supination is best managed with an anterior tibialis transfer to the lateral cuneiform.
During clubfoot surgery for residual or recurrent deformity, preservation of vascular supply should be the number one priority. Absence or a substantial reduction in the size and flow of the anterior tibial artery occurs in approximately 90% of limbs with clubfoot. Preservation of the posterior tibial artery should be a surgeon’s number one priority. One should consider not fully exsanguinating the foot prior to tourniquet inflation in order to visualize the posterior tibial neurovascular bundle. Although uncommon, the posterior tibial artery may be absent in a clubfoot.9 If the posterior tibial vascular bundle cannot be located at the time of surgery, even after the tourniquet is taken down, a hypertrophied peroneal vascular bundle may be present and should be carefully protected.
Metatarsus Adductus
It is hard to get in trouble with this condition as long as you make the right diagnosis and don’t treat it. First, make certain there is normal ankle dorsiflexion; if not, it is not metatarsus adductus (MTA) and may be a clubfoot. Look at the hindfoot; if there is significant valgus, think of a skewfoot (Fig. 29-4). It may be difficult to differentiate between MTA and skewfoot with radiographs in infants as the navicular is not yet ossified (Fig. 29-5). MTA may also be confused with a metatarsal longitudinal epiphyseal bracket (Fig. 29-6).
Figure 29-5 Serial radiographs of the less involved right foot from Figure 29-4 confirm that this is a classic skewfoot. The initial radiographs at presentation (A) are inconclusive and could be metatarsus adductus or skew foot. B: With time and further development, it becomes clear the navicular is laterally displaced (arrow) on the head of the talus and the forefoot is adducted on the midfoot. In combination with hind foot valgus, this is considered a skewfoot. |
In the extraordinarily unlikely event that surgery is needed for MTA, do not do a capsular release as this leads to poor results. We recommend an osteotomy of the medial cuneiform, rather than the first metatarsal, both to avoid the proximal physis of the first metatarsal, and for better correction. Lateral osteotomies may be of the second to fifth metatarsals or the cuboid.
Positional Calcaneovalgus
This is a very common deformity in newborns. Although the appearance of the foot may be striking and can be confused with congenital vertical talus, spontaneous correction is the rule (Fig. 29-7). Having the parents perform stretching exercises may help the babies a little, but it can help the parents a lot and will keep the grandparents happy that something is being done. “Apparent calcaneal valgus feet” may in fact be posterior medial bowing of the tibia, which usually corrects spontaneously but may result in a 3- to 6-cm leg length discrepancy at maturity.
Congenital Vertical Talus
Congenital vertical talus (CVT) is an uncommon foot deformity in young infants and may not be quite as obvious as some other foot deformities. CVT is characterized by a flat everted foot, which, in some respects, has the opposite appearance of a clubfoot, in which the foot is in cavus and inversion. Both deformities have Achilles tendon contractures. In the clubfoot, the equinus deformity is obvious. In CVT, the ankle doesn’t appear to be in equinus because of the dorsiflexion contracture of the anterior/dorsal structures. This results in a midfoot breech with a rocker bottom and plantar prominence of the talar head (makes foot look flat). To stay out of trouble, the provider has to do three things:
Confirm the diagnosis of CVT in contradistinction to an oblique talus, positional calcaneovalgus, posteromedial bowing of the tibia, or is just a really flat foot (Fig. 29-8).
Determine whether the child with CVT has one of the associated diagnoses that are present in 50% of patients. (Consider genetics and neurology consults.)
Treat the CVT foot with Dobbs method of correction.
By definition, CVT is a fixed dorsal dislocation of the navicular on the head of the talus. As the navicular is not ossified until about 3 years of age, and cannot be seen on plain radiographs, we rely on the relationship of the axis of the talus and the first metatarsal. The diagnosis is confirmed on the plantar flexed lateral radiograph by observing that the axis of the talus passes plantar to that of the first metatarsal (Fig. 29-8B and C). Avoid the pitfall of believing that if the two axes become parallel,
there is no vertical talus. Dorsal translation of the first metatarsal axis in relation to that of the talus indicates dorsal dislocation at the talonavicular joint (Fig. 29-9). The axis of the talus remains vertically aligned with the axis of the tibia on the dorsiflexion lateral radiograph. An oblique talus is on the spectrum between flat foot and CVT; consider it a CVT without a lot of anterior contracture and without dislocation of the navicular. It is characterized by incomplete dorsiflexion of the talus in the ankle mortice, as seen on the dorsiflexion lateral view (normal is 90°) (Fig. 29-10A). There is fair alignment of the talus and first metatarsal on the plantar flexion lateral radiograph (Fig. 29-10B). The exact definition of an oblique talus is debated, but stretching and heel cord tenotomy may be effective.
there is no vertical talus. Dorsal translation of the first metatarsal axis in relation to that of the talus indicates dorsal dislocation at the talonavicular joint (Fig. 29-9). The axis of the talus remains vertically aligned with the axis of the tibia on the dorsiflexion lateral radiograph. An oblique talus is on the spectrum between flat foot and CVT; consider it a CVT without a lot of anterior contracture and without dislocation of the navicular. It is characterized by incomplete dorsiflexion of the talus in the ankle mortice, as seen on the dorsiflexion lateral view (normal is 90°) (Fig. 29-10A). There is fair alignment of the talus and first metatarsal on the plantar flexion lateral radiograph (Fig. 29-10B). The exact definition of an oblique talus is debated, but stretching and heel cord tenotomy may be effective.
Figure 29-10 A: Child with an oblique talus. Note that this radiograph shows a quite similar relationship between the talus and first metatarsal as that seen in Figure 29-9. B: With plantar flexion, the axis of the talus and first metatarsal significantly change their relationship. |
THE GURU SAYS…
During the pinning of the talonavicular joint in the operating room, at times it is necessary to open the joint to ensure reduction. Also it is important to pin the talonavicular joint before performing the Achilles tenotomy. This allows for the foot to be a lever for dorsiflexion. Burying the pin can extend the time that it is in place (up to 8 weeks casting).
TODD A. MILBRANDT
Clubfeet and CVT are different in shape, and patients with CVT are also more likely to have an associated condition; yet historically, they both share a similar evolution toward nonoperative treatment. In the past, the CVT foot was treated with extensive surgical release just as clubfeet were treated with wide posterior medial release. Ponseti developed his nonoperative method of treatment for clubfoot, and it is no small coincidence that one of his protégés, Dr. Matt Dobbs, developed a similar approach for CVT. With his method, the foot is manipulated by plantar flexing and inverting the forefoot against plantar-medial pressure on the head of the talus (Fig. 29-11). Serial manipulations and long leg cast applications are carried out just as with clubfoot management. Once the anterior tibialis and long toe extensors have stretched and the talonavicular joint is aligned, the child goes to the operating room for talonavicular joint pinning and Achilles tenotomy (Fig. 29-12).
Figure 29-13 A: In normal weight-bearing position, this patient has a very flat foot. B: When standing on his toes, the arch is visible. This dynamic change with foot position defines a flexible flatfoot.
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