Clubfoot, which has an incidence of about 1 per 1,000 live births, usually occurs bilaterally and is twice as common in boys as it is in girls. It may be associated with other birth defects, such as myelomeningocele, spina bifida, and arthrogryposis. Clubfoot is correctable with prompt treatment.
Causes
A combination of genetic and environmental factors in utero appears to cause clubfoot. Heredity is a definite factor in some cases, although the mechanism of transmission is undetermined. If a child is born with clubfoot, his sibling has a 1 in 35 chance of being born with the same anomaly. Children of a parent with clubfoot have 1 chance in 10.
In children without a family history of clubfoot, this anomaly seems linked to arrested development during the 9th and 10th weeks of embryonic life, when the feet are formed. Researchers also suspect muscle abnormalities, leading to variations in length and tendon insertions, as possible causes of clubfoot.
Signs and symptoms
Talipes equinovarus varies in severity. Deformity may be so extreme that the toes touch the inside of the ankle, or it may be only vaguely apparent.
In every case, the talus is deformed, the Achilles tendon shortened, and the calcaneus somewhat shortened and flattened. Depending on the degree of the varus deformity, the calf muscles are shortened and underdeveloped, with soft-tissue contractures at the site of the deformity. The foot is tight in its deformed position and resists manual efforts to push it back into normal position.
Clubfoot is painless, except in older, arthritic patients. In older children, clubfoot may be secondary to paralysis, poliomyelitis, or cerebral palsy, in which case treatment must include management of the underlying disease.
Diagnosis
An early diagnosis of clubfoot is usually no problem because the deformity is obvious. With subtle deformity, however, true clubfoot must be distinguished from apparent clubfoot (metatarsus varus or pigeon toe).
Apparent clubfoot results when a fetus maintains a position in utero that gives his feet a clubfoot appearance at birth. This can usually be corrected manually.
Another form of apparent clubfoot is inversion of the feet, resulting from the peroneal type of progressive muscular atrophy and progressive muscular dystrophy. With true clubfoot, X-rays show superimposition of the talus and the calcaneus and a ladderlike appearance of the metatarsals.
Treatment
Appropriate treatment for clubfoot is administered in three stages:
- correcting the deformity
- maintaining the correction until the foot regains normal muscle balance
- observing the foot closely for several years to prevent the deformity from recurring.
Sequential correction
Clubfoot deformities are usually corrected in sequential order: forefoot adduction first, then varus (or inversion), then equinus (or plantar flexion). Trying to correct all three deformities at once only results in a misshapen, rocker-bottomed foot.
Forefoot adduction is corrected by uncurling the front of the foot away from the heel (forefoot abduction); the varus deformity is corrected by turning the foot so the sole faces outward (eversion); and finally, equinus is corrected by casting the foot with the toes pointing up (dorsiflexion). This last correction may have to be supplemented with a subcutaneous tenotomy of the Achilles tendon and posterior capsulotomy of the ankle joint.
Treatment methods
Several therapeutic methods have been tested and found effective in correcting clubfoot. The first is simple manipulation and casting, whereby the foot is gently manipulated into a partially corrected position, then held there in a cast for several days or weeks. (The skin should be painted with a nonirritating adhesive liquid beforehand to prevent the cast from slipping.)
After the cast is removed, the foot is manipulated into an even better position and casted again. This procedure is repeated as many times as necessary. In some cases, the shape of the cast can be transformed through a series of wedging maneuvers, instead of changing the cast each time.
After correction of clubfoot, proper foot alignment should be maintained through exercise, night splints, and orthopedic shoes. With manipulating and casting, correction usually takes about 3 months. The Denis Browne splint—a device that consists of two padded, metal foot plates connected by a flat, horizontal bar—is sometimes used as a follow-up measure to help promote bilateral correction and strengthen the foot muscles.
Resistant clubfoot may require surgery. Older children, for example, with recurrent or neglected clubfoot usually need surgery.
Tenotomy, tendon transfer, stripping of the plantar fascia, and capsulotomy are surgical procedures that may be used. With severe cases, bone surgery (wedge resections, osteotomy, or astragalectomy) may be appropriate. After surgery, a cast is applied to preserve the correction.
Whenever clubfoot is severe enough to require surgery, it’s rarely totally correctable. However, surgery can usually ameliorate the deformity.
Special considerations
- Look for any exaggerated attitudes in an infant’s feet. Make sure you can recognize the difference between true clubfoot and apparent clubfoot. Don’t use excessive force in trying to manipulate a clubfoot. The foot with apparent clubfoot moves easily.
- Stress to the parents the importance of prompt treatment. Make sure theyunderstand that clubfoot demands immediate therapy and orthopedic supervision until growth is completed.
- After casting, elevate the child’s feet with pillows. Check the toes every 1 to 2 hours for temperature, color, sensation, motion, and capillary refill time; watch for edema. Before a child in a clubfoot cast is discharged, teach parents to recognize circulatory impairment.
- Insert plastic petals over the top edges of a new cast while it’s still wet to keep urine from soaking and softening the cast. When the cast is dry, “petal” the edges with adhesive tape to keep out plaster crumbs and prevent skin irritation.
- Perform skin care under the cast edges every 4 hours, washing and drying the skin thoroughly. (Don’t use oils or powders; they tend to macerate the skin.)
- Warn parents of an older child not to let the foot part of the cast get soft and thin from wear. If it does, much of the correction may be lost.
- If the wedging method is being used, frequently check circulatory status; it may be impaired because of increased pressure on tissues and blood vessels. The equinus correction especially places considerable strain on ligaments, blood vessels, and tendons.
- After surgery, elevate the child’s feet with pillows to decrease swelling and pain. Watch for signs of discomfort or pain. Try to locate the source of pain—it may result from cast pressure, not the incision. If bleeding occurs under the cast, circle the location and mark the time on the cast. Watch for indications that the bleeding is spreading.
- Explain to the older child and his parents that surgery can improve clubfoot with good function but can’t totally correct it; the affected calf muscle will remain slightly underdeveloped.
- Emphasize the need for long-term orthopedic care to maintain correction. Teach the parents the prescribed exercises that their child can do at home.
- Urge the parents to be sure their child wears corrective shoes, as ordered, and splints during naps and at night.
No comments:
Post a Comment