Congenital Hand Conditions
A congenital anomaly is one noted at birth. Anomalies can be relatively minor (such as an angulation of the small finger: clinodactyly) or can be more major (such as hypoplasia or absence of the thumb). The care of children with congenital hand anomalies usually involves a team of healthcare professionals. Most congenital-hand surgery is carried out in hospitals with experience in the care of children.
The birth of a child with a hand anomaly has a profound and immediate emotional impact. Expert advice, in the first few days or weeks after birth, should provide reassurance and help dispel inappropriate fears. If a hand anomaly is observed at the 18-20 week fetal anomaly scan, an appointment can be arranged prior to birth.
The parents should be provided with an explanation of:
The likely diagnosis.
The incidence of the individual anomaly.
An explanation of the likely cause of the anomaly.
The incidence of congenital hand anomalies is at most 1/200 births. A single gene mutation is present in most cases, teratogenic, and vascular disruption can also be implicated. Syndactyly (fused-digits) and polydactyly (extra-digits) are the most common anomalies. (Trigger thumb is relatively common in children but is not a congenital anomaly, as it is not seen at birth). Surgery is considered appropriate in about two thirds of children with hand anomalies.
A significant proportion of children with hand anomalies, particularly those children with anomalies on the pre-axial (radial) side of the limb, will have anomalies affecting other organs, such as the heart or kidneys.
Early assessment by a paediatrician, can be helpful in order to confirm the diagnosis of a particular syndrome (such as Holt-Oram), and to help the prioritization of different elements of the child’s-care. A separate appointment with a consultant in clinical genetics can help quantify the likely risk for siblings and future off-spring.
For most children radiological (X-ray) examination of the limb is unlikely to helpful in the first months after birth, and can be delayed until a second consultation, usually between 10 and 14 months of age.
Some anomalies can require earlier intervention: radial dyplasia may require splinting or soft tissue distraction, constriction bands causing finger tip oedema might need division, complex syndactyly of the border digits causing a flexion contracture of the shorter digits might need release.
Patterns of grip start to develop in the first year of life, basic control of the hand is established by about three years, the majority of congenital hand surgery is carried between one and four years of age.
Many of the children with congenital hand anomalies will have other medical problems. Surgery should be timed to minimize the number of visits to hospital and the number of general anaesthetics given to younger children.
The objectives of surgery include correction of skeletal and soft-tissue mal-alignment. Extra bones, mal-positioned bones, and abnormal fusions should be corrected at the first operation. Early alignment of the joint surfaces at 90°to the axis of the digit reduces the potential for deformity during growth.
Abnormal attachment, connection and alignment of tendons should be corrected. Initial surgery, for example for thumb duplication, should include a thorough assessment and correction of both bone and soft tissue abnormalities. Failure to recognize the abnormalities at any initial surgery can result in a higher rate of secondary surgery.
Children should be followed up (at increasing infrequent intervals) until they reach skeletal maturity. Changes in the demands placed upon the hands, associated with increasing intensity of course-work or exams can be addressed by assessment by an occupational therapist. Adaptions in patterns of hand use or adaptions in the educational environment can avoid the child potentially falling behind his/her peers.
The care of a child with a congenital hand anomaly is likely to be a relationship that lasts for a significant proportion of a clinicians’ career. Careful documentation and audit over many years is needed to help make the best possible decisions for the care of future generations with congenital hand anomalies.