How To Treat Polysyndactyly And Syndactyly Of The Foot
Other Pertinent Insights On Reducing Complication Risk
Whenever possible, the respective surgeons should perform repair of combined congenital deformities of the hand and foot together. Obviously, a single anesthesia is advantageous. However, the additional benefit is that skin harvested from a congenital toe abnormality can be a full thickness skin graft for a finger.40
Whenever possible, one should use an absorbable suture not only in cases of syndactyly and polydactyly repair, but also in most other pediatric foot surgeries.41 This spares the child and the surgeon the difficulty of removing a large number of non-absorbable sutures.
It is also important to keep in mind that the surgeon should never attempt desyndactyly or any intervention on both sides of a toe in those cases of syndactyly and polysyndactyly involving three adjacent toes. The risk of vascular complications is overwhelming and there is an extremely high likelihood of ischemia of two or all three of the involved toes with disastrous complications and major digital loss.
In spite of apparently successful correction of tibial polydactyly, progressive varus deformity of the hallux may persist and, in some cases, worsen. This is due in part to the development of the adaptive medial position of the metatarsal articular surface. In very young children, there is a high potential for remodeling resulting in better alignment of the articular surface. Deviation may also be due to persistent tethering of deep soft tissue along the medial side of the foot that is caused by remnants of an incompletely formed medial ray.
The longitudinal epiphyseal bracket occasionally occurs in polydactyly and polysyndactyly. In this deformity, rather than having a single epiphysis located at the end of a bone, the epiphyseal plate and the epiphysis itself wraps around one side of the involved bone.42 This causes a restriction of growth on one side with overall shortening of the bone but allows some longitudinal growth on the opposite side. The result is shortening and angular deformity.43,44 When it occurs in the first metatarsal, the result is varus deformity.45 The longitudinal epiphyseal bracket is present in 2 to 14 percent of congenital foot and hand deformities.46 This lesion has only been reported in short tubular bones with epiphyses located at the proximal ends of the bones. This limits the deformity to the phalanges and first metatarsal.
Treatment is by bracket excision.43,47-49 Before epiphyseal ossification, one can simply excise the bracket. Once ossification occurs, it is necessary to place something in the void in order to prevent the bracket from reestablishing. This can be fat harvested from areas adjacent to the surgery or one can place a strip of methyl methacrylate against the diaphysis after excision of the bracket.
Repair of these deformities is very rewarding both for the patient and the surgeon. Results are instantaneous and immediately apparent.
However, there is the potential for serious and irreversible error when the surgeon does not take the time to evaluate the anatomy carefully so goals and objectives become realistic and he or she can avoid complications. Some semblance of normal function is the major goal but surgeons cannot totally ignore the cosmetics. Specific issues are scar formation, appropriate tissue color and texture match, creation of an acceptable web space, flap development and skin grafting, and maintenance of joint motion.
Technical skills notwithstanding, careful evaluation of the clinical appearance of the parts and the radiographs is the most important component in ensuring a good result. This type of surgery reinforces the old adage “measure twice, cut once.”
Dr. Harris is a Clinical Associate Professor in the Department of Orthopaedics and Rehabilitation at the Loyola Medical Center in Maywood, Ill. He is a Fellow of the American College of Foot and Ankle Surgeons.