Congenital Foot Deformities: A Guide To Conservative Care

pt08_congenital_pic0.jpg [3]

pt08_congenital_pic1.jpg [4]

pt08_congenital_pic2.jpg [5]

pt08_congenital_pic3.jpg [6]

pt08_congenital_pic4.jpg [7]

pt08_congenital_pic5.jpg [8]

The early recognition and treatment of congenital foot deformities is essential in order to ensure optimal functioning of the foot. In regard to joint deformities caused by contracture of muscles and capsule, one can achieve correction via methods including: repeated gentle manipulation stretching of the tight structures; cast immobilization of the joints in the position of correction; and shoe/splint therapy. These forms of conservative therapy are of particular value in the correction of such congenital deformities as talipes equinovarus or clubfoot, metatarsus adductus and talipes calcaneovalgus.

When one initiates and properly performs these procedures in a timely manner, podiatric physicians can expect to correct at least 50 percent of talipes equinovarus deformities and over 90 percent of the feet affected by metatarsus adductus and talipes calcaneovalgus. In regard to conservative management of congenital foot deformities, the goals are reducing the need for surgery and, when surgery is inevitable, limiting its extent as much as possible.

Stretching exercises are most often recommended as the first line of treatment for congenital foot deformities. To be effective, patients must do the exercises aggressively and frequently, and as soon after birth as possible. In all cases, however, a careful clinical assessment should precede any form of conservative therapy.

When it comes to a thorough clinical assessment of a patient with a talipes equinovarus deformity, the examiner must feel the calcaneal contour to determine whether the calcaneus is in place or not. With this deformity, the calcaneus is usually pulled proximally away from the heel pad with the small heel being drawn up and rolled in under the talus in an inverted position. Clinicians can palpate the talar head dorsolaterally at the midfoot. It is usually lined up with the patella but may be plantarflexed. The examiner should try to reduce the foot deformities in the horizontal (adduction), sagittal (equinus) and frontal (varus) planes in order to assess the reducibility of the foot as doing so is essential to success. One must also evaluate overall muscle tone since signs of spasticity can significantly increase the difficulty in obtaining correction.

Key Insights On Manipulation Therapy
Classifying the clubfoot is often useful in monitoring the effectiveness of the treatment. When it comes to clubfoot, there are four classification categories: benign, moderate, severe and very severe. Benign indicates totally reducible feet. Moderate clubfoot denotes reducible, partially resistant feet. With severe clubfoot, podiatrists are looking at resistant, partially reducible feet. Very severe clubfoot denotes irreducible feet.

The success of manipulations increases as the foot becomes reducible. This classification system allows us to monitor the evolution of reducibility throughout treatment.

While manipulation therapy is most commonly used in the United States as a prelude to applying a cast for the correction of a clubfoot deformity, the therapy, as developed by Bensahel with Guillaume and the staff of Robert Debre Hospital, has met with some success as the primary treatment for this condition. In either case, manipulation of a clubfoot requires a good deal of experience. Indeed, the practitioner should have a strong understanding of the anatomic pattern of the clubfoot.

In order to correct the deformity via manipulation therapy, one must make the following three changes.

• Move the navicular from its set medial position on the medial malleolus.
• Mobilize the distal part of the calcaneus, which is associated with the head of the talus.
• Displace the posterior part of the calcaneus proximally and laterally. One must bring the posterior part back medially and distally.

Hold the talus firmly throughout manipulation. This functional manipulation method is sequential and includes the decoaptation of the navicular from the medial malleolus, abduction of the calcaneo-forefoot component around the talus and correction of equinus.

One must perform these manipulations at least once every day in order to avoid excessive pressure and stress of the fibrous soft tissue on the cartilage. Practitioners found they obtained the maximum amplitude of correction while the baby was sleeping. Muscle stimulation and a bandage complete the manipulations. Perform stimulation of the peroneal muscles with the fingertips or a toothbrush all along the lateral aspect of the foot and leg. In addition to this, ask the mother to tickle the baby’s bandaged foot as often as possible at the level of the fifth toe. The aim is to reduce the deformity quickly without going so fast as to damage the foot. Improper manipulation can lead to a risk of false correction and a rocker-bottom foot deformity.

In a review of 338 clubfeet from 1974 to 1978, Bensahel, et al., found that manipulation therapy facilitated good results in 48 percent of the patients. Fifty-two percent of the cases required supplemental surgery. At the Montpellier Hospital, Dimeglio used a similar method, combining manipulation therapy and a passive motion machine and plaster, which achieved even better results. Out of the 200 clubfeet treated in this manner from 1991 to 1997, 74 percent of the feet were never subject to surgery. The authors of these studies do stress, though, that intense specialized physiotherapy is necessary at all phases of treatment in order to obtain good results.

How To Address Metatarsus Adductus
Metatarsus adductus is a deformity that lends itself to early stretching/manipulation management. Although many physicians recommend prolonged observation since metatarsus adductus can spontaneously resolve, there is enough evidence to justify treatment.

Rushforth reviewed 179 untreated feet in 116 children with metatarsus adductus who were examined at less than 1 year of age and then again at 3 to 11 years of age. In the follow-up, the researchers found that although 58 percent of patients had no deformity, 42 percent retained deformities ranging from mild to severe. Retained metatarsus adductus reportedly causes foot pain due to shoe fitting and wear problems, and also promotes hallux valgus development. Researchers have found metatarsus adductus in 22 percent to 75 percent of patients with adolescent hallux valgus.

When examining an infant with suspected metatarsus adductus, it is most important to differentiate this deformity from the more pathologic talipes equinovarus. With metatarsus adductus, the foot is C-shaped and the medial border of the foot is concave with its apex at the first metatarsocuneiform joint. The lateral side is convex with a prominent fifth metatarsal base. Most importantly, the ankle joint has normal dorsiflexion and plantarflexion, and the subtalar joint has normal inversion and eversion. The rearfoot should be in neutral or slight valgus, not varus.

Although one may initiate stretching exercises as early as desired, since metatarsus adductus is a much more easily corrected condition than talipes equinovarus, and there is a percentage of cases that spontaneously correct, I recommend waiting on corrective treatment until the baby is one to two months of age. This also makes it easier to grasp the slightly larger foot for more accurate stretching. Placement of the hands of the person performing the exercise must be exact.

What About Talipes Calcaneovalgus And Congenital Convex Pes Valgus?
Talipes calcaneovalgus is a common and relatively benign flexible deformity. It is often referred to as the “up and out” deformity because there is a marked dorsiflexion and eversion of the foot with a valgus attitude of the heel. The dorsum of the foot actually may rest against the anterior aspect of the tibia. Plantarflexion is limited to the neutral position with the anterior soft tissue structures appearing tight and preventing further plantarflexion of the foot. Most often, this condition responds rapidly to stretching of these tightened structures in early infancy.

Congenital convex pes valgus is a severe condition that presents an appearance at birth similar to talipes calcaneovalgus. Accordingly, podiatrists must differentiate between the two. With both deformities, the forepart of the foot is dorsiflexed and everted, and there is a limitation of plantarflexion and inversion. The heel in congenital convex pes valgus is in equinus position, the sole is convex and the deformity is very rigid. Convex pes valgus conditions usually do not respond to conservative treatments and often require surgical correction with a high recurrence rate.

A Guide To Serial Casting
Serial casting is the most frequently used regimen of treatment for these congenital foot deformities because it maximizes the corrective force at the deformity, is reproducible and is cost effective.

Ideally, two people should perform the technique for casting, with one wrapping and the other holding the foot and molding the cast. Most casts applied to young infants extend to the upper thigh with the knee flexed. Applying the casts in two parts, the short leg first and the above knee later, allows for more control during molding. Apply a thin, smooth layer of cast padding with extra padding on the bony prominences and the heel. One can use a small piece of stockinet on the thigh for neatness and to prevent chafing. Plaster casting material is the preference of many due to the ease of molding.

Although Ponseti had developed his plaster cast method for the correction of the talipes equinovarus deformity in 1963, it has only recently received a renewed following and appears to be the most successful current technique.
This technique involves brief manipulation and then casting in maximum correction. After approximately five casting periods, the adductus and varus are corrected. One would perform a percutaneous heel cord tenotomy in most feet to complete the correction of the equinus. Then place the foot in the last cast for three weeks. Maintain this correction via night splinting, using a foot abduction brace until the child is 2 to 4 years of age.

Consider cast correction for a metatarsus adductus deformity. When correcting the right foot, for example, the left hand of the individual molding the cast cups the heel with the thumb placed proximal to the base of the fifth metatarsal to act as the molding counterpoint for the forefoot correction. Use the right hand to grasp the entire forefoot and direct it laterally. One must mold the entire forefoot as a unit. Applying pressure only against the first metatarsal head does not provide enough control. Although the length of time required for correction varies, casting for at least six to eight weeks with biweekly cast changes and the subsequent use of splinting and shoe therapy is standard.

If one does not achieve correction with three to four weeks of proper manipulation of the foot with a talipes calcaneovalgus deformity, then serial immobilization casting is appropriate. Hold the foot in the cast with the calcaneus in slight varus, the foot in slight equinus and the forefoot in neutral.

Can Corrective Shoes And Splints Have An Impact?
Once one has obtained full correction of the foot, it is usually advisable to maintain this correction with the use of an orthopedic appliance. Clinicians can use rotational bars, shoes and adjustable footwear for this purpose. Shoe therapy can also be the primary treatment modality in cases of mild flexible metatarsus adductus and talipes calcaneovalgus foot deformities.

In order to maintain correction for a clubfoot or metatarsus adductus deformity, one should substitute the cast for corrective shoes placed on a splint such as a Denis Browne splint. To maintain the correction, clinicians need to consider two key mechanical factors: the external rotation of the shoes on the bar (usually 30 to 45 degrees external) and the force placed on the foot by the shoes. To prevent a valgus thrust at the rearfoot, bend the bar in the shape of a V when treating metatarsus adductus.

Two commonly used shoes are the open toe straight last shoe and the open toe abducted last shoe. The open toe abducted last shoe has a C-shaped last that is abducted both in the forefoot and the rearfoot. One should only use this shoe for clubfoot treatment.
Clinicians can further enhance the function of these shoes by placing adhesive felt padding in the shoes when treating metatarsus adductus or clubfoot. One would pad the shoe from the distal end of the medial side of the shoe and end at the area of the first metatarsal base on the lateral side at the area of the cuboid. When using these shoes to help treat metatarasus adductus, one can add a varus heel pad.

When treating a patient with a calcaneovalgus deformity, clinicians should institute open toe straight last shoes and incorporate foot orthoses to help maintain proper foot alignment after a stretching or casting regimen. Podiatrists have used adjustable shoe orthoses with success in the treatment of metatarsus adductus. A shoe with a “break” and hinge device in the midfoot area can guide and maintain correction.

Discontinuance of maintenance of correction has consistently shown a recurrence of the deformity. For this reason, many authors recommend using post-correction orthopedic devices for periods as long as five years after the initial correction of the deformity.

For further reading, see “How To Address Pediatric Intoeing” in the January 2007 issue of Podiatry Today.

References:

1. Bensahel H, Guillaume A, Czukonyi Z, et al. Results of physical therapy for idiopathic clubfoot: A long-term follow-up study. J Pediatr Orthop 1990; 10:189.
2. Bensahel H, Guillaume A, Czukonyi Z, et al. The intimacy of clubfoot: The ways of functional treatment. J Pediatr Orthop 1994; 3:155.
3. Caselli MA, Sobel E, McHale KA. Pedal manifistations of musculoskeletal disease in children. Clin Podiatr Med Surg 1998; 15 (3):481.
4. Caselli MA. The role of shoe therapy in the management of pediatric congenital clubfoot. Podiatry Management 2004; 23(8):125.
5. Coughlin MJ. Roger A Mann Award. Juvenile hallux valgus etiology and treatment. Foot Ankle Int 1995; 16:682.
6. Dimeglio A, Dimeglio F. Clubfoot. In Fitzgerald RH Jr.,Kaufer H, Malkani AL (eds). Orthopaedics. Missouri, Mosby, Inc. 2002 pp 1475-1489.
7. McHale K. Metatarsus adductus. In Myerson MS (ed): Foot and Ankle Disorders. Philadelphia, W.B. Saunders Company. 2000 pp 673-692.
8. Pontious J, Mahan KT, Carter S. Characteristics of adolescent hallux abducto valgus: a retrospective review. J Am Podiatr Med Assoc 1994; 84:208.
9. Rushforth GF. The natural history of hooked forefoot. J Bone Joint Surg Br 1978; 60:530.
10. Staheli L. Clubfoot: Ponseti Management, Second Edition. Seattle, Global-HELP Organization. 2005.
11. Sullivan RJ. Congenital talipes equinovarus. In Myerson MS (ed). Foot and Ankle Disorders. Philadelphia, W.B. Saunders Company. 2000 pp 693-710.