Webbed fingers – depending on which fingers are fused together – can bother children and affect social relationships. As a result, these deformities can lead to stress, poor self-esteem, and introversion. If deformities affect the first or last web space, length discrepancies may cause deformities during growth. Syndactyly surgery, as most may assume, is not as simple as separating the digits’ skin. This is because fingers can be conjoined by not only skin, but by bone and ligament as well. Furthermore, even if fingers were fused together by skin – and nothing else – there wouldn’t be enough skin to cover exposed soft and hard tissues. To find out more about how syndactyly surgeries are carried out, we speak to three Consultant Plastic and Reconstructive Surgeons as they explain how deformities arise, how procedures are carried out, and why holistic post-operative care is just as important as corrective surgery.
According to Dr. Shah Jumaat and Dr. Nur Shazwani Farah, the term ‘syndactyly’ derives from the Greek words ‘syn’ – together – and ‘dactylos’ – digit. It can occur due to failure of digital separation during gestational periods, or following burn trauma and tissue contracture. Dr. Salina Bt Ibrahim says syndactyly is the commonest of all congenital hand deformities, with incidences occurring between 1:1000 and 1:3000 births. Webbed fingers can be an isolated incident or associated with a genetic syndrome. If familial, it is inherited as a dominant gene where 10 to 40 percent of births may be affected. There are over 300 genetic syndromes that involve syndactyly, such as Apert, Poland and Saethre-Chotzen syndrome. A syndromic child may similarly experience associated disorders including brain, craniofacial or cardiac abnormalities. As such, it’s important that doctors ascertain if conditions are isolated incidents or caused by genetic syndromes.
In terms of the condition’s physical traits, the third, fourth, second and first interdigital webs are affected in decreasing order of frequency. Dr. Jumaat and Dr. Nur explain, “The middle finger is most commonly affected (58 percent), followed by the ring-little finger web (27 percent), middle-index web (14 percent) and thumb-index (1 percent).” Where syndactyly is affected by Apert Syndrome, syndactyly can occur in both hands and toes. While most cases affect a minimum of three digits on each hand and foot, all digits could be fused together.
How is the deformity classified?
Dr. Salina says that syndactyly may be noted as complete or incomplete. She states, “Complete syndactyly involves digits united throughout their length”. This means that the webbing extends all the way to the fingertips. Incomplete syndactyly, Dr. Salina explains, is “Involved webbing at various lengths of the adjacent digits,” where joining doesn’t extend all the way. The deformity is similarly noted as simple or complex. In simple syndactyly, only the skin and soft tissues are united. In complex syndactyly, there is bony or bony cartilage fusion between adjacent digits. Dr. Salina affirms, “These bony fusions may affect all the phalanges or occur only at the fingertips. A plain x-ray will confirm presence of bony fusion.”
When is surgery recommended?
Dr. Jumaat and Dr. Nor agree detachment surgery may occur as early as 12-months old or as late as five-years old (before schooling age). This is because there’s no urgency for surgery when deformities do not affect digital growth. Dr. Salina clarifies, “Complex syndactyly tends to aggravate the deformity and impede growth of adjacent digits, so early release should be undertaken.” Dr. Jumaat and Dr. Nur further add that attachments or thumb-index or little-ring fingers require early intervention, as length discrepancies may hinder growth. Otherwise – and if patients don’t present these traits – it’s best that surgical intervention be held off until children start school.
The aims of syndactyly surgery and how the procedure is performed.
The aim of surgery is to create a commissure between the two digits (space between the digits), separate the two digits, and provide skin cover after the release, with full thickness skin grafts, Dr. Salina says. She does however caution parents that indications and expected outcomes aren’t always aesthetically pleasing, as patients may be left with scarring and hyperpigmentation of the skin graft. Surgery is performed under general anaesthesia and tourniquet control, by creating a flap for the commissure and a zigzag skin incision to separate the digits. Areas that are lacking skin will usually utilise skin taken from the groin. The groin region however, will be stitched primarily after tissue harvesting. During surgery, care must be taken to preserve the digital neurovascular structures. This is to ensure patients don’t suffer complications like numbness or ischemia. Finally, surgery for multiple syndactyly cannot be done in one sitting, due to risks of digital vascularity, delayed wound healing and severe scarring.
Dr. Jumaat and Dr. Nur explain that post-operative dressing and physiotherapy is determined by surgical types. In Dr. Salina’s practice, affected digits are wrapped in well-padded dressings to prevent bleeding and protect the skin graft. Dressings will also be applied on the groin if skin grafts have been taken. Postoperative painkillers and a circulation chart – which monitor colour, sensation and temperature – will be issued. Digital dressings are usually kept intact for at least five days to allow skin grafts to heal. The dressing on the groin may be changed according to requirements, and later exposed once it is dry. Dr. Salina discloses that skin grafts are normally stable after two weeks. After the initial five days, dressings can be changed on a weekly basis until wounds are completely dry. Last but not least, Dr. Jumaat and Dr. Nur note that physiotherapy is an integral part of the post-operative regime to achieve better range of motion and reduced instances of scar contracture and follow-up surgery.
Dr. Salina affirms that full range of motion is regained after bandages are removed. Dr. Jumaat and Dr. Nur always recommend regular check-ups, as doctors need to monitor patients and decide if additional procedures may be needed for improved digital function. A commonly occurring complication is scar contractures along web spaces. Should such problems arise, revisional surgery may be necessary to recreate web spaces.