Syndactyly is a common congenital anomaly. It is generally treated surgically. De-syndactyly surgery is based on timing and the type of syndactyly. There are various ways to do the surgery, for example, using flaps to reconstruct the area. The outcome for simple syndactyly is favorable as compared to complex syndactyly.
What Is Syndactyly?
Syndactyly is a common anomaly of the extremities that have been present since birth. There is a fusion of the soft tissues or the bones of the digits in the upper or lower limbs. Syndactyly can also be seen with certain genetic disorders like Apert and Poland syndrome. The treatment is usually a surgical separation of the digits for proper movement of the digits.
What Are the Types of Syndactyly?
Depending on the presence or absence of the fusion, it is differentiated into simple or complex. In complete syndactyly, the fusion extends up to the fingertips involving the nail folds. In incomplete syndactyly, the fusion does not involve the complete finger. In complicated syndactyly, there is a presence of extra or accessory digits or bones. Mostly found between the second and third toes and between the middle and the ring finger.
What Are the Indications of De-syndactyly Surgery?
De-syndactyly is indicated in almost all cases of syndactyly as it leads to the independent movement of the digits.
What Are the Contraindications of De-syndactyly Surgery?
The contraindications of de-syndactyly surgery are as follows:
Incomplete syndactyly that does not affect daily functions.
Certain medical conditions.
Complex syndactyly that may lead to further risk post-separation.
When Can De-syndactyly Surgery Be Carried Out?
Since syndactyly is present since birth, surgical procedures can be scheduled even at five to six months of age. Scheduling surgeries before this age may lead to complications due to anesthesia. In case of a nail infection, the parents are instructed to wash the hand of the child with soap and water and apply an antibacterial ointment on it. If needed, oral antibiotics can also be given.
The timing of the de-syndactyly surgery depends on the number of digits involved and the type of syndactyly. If more digits are involved, then the surgery can be performed as soon as possible. Early surgery can help prevent the faulty rotation and angulation that progresses with the growth of the different fingers. In complex syndactyly cases, the first surgery is performed when the baby is six months old. This is due to different rates of growth of the small and the ring finger or between the index finger and the thumb. If syndactyly is not treated promptly in between these fingers, then it may lead to permanent malformations. In case of the presence of several syndactylies in the same hand, simultaneous de-syndactyly can be performed, with the consideration that one side of the finger is released. In the case of syndactyly involving both hands, the surgery can be performed in one go.
Multiple surgeries can be carried out in individuals with syndactyly involving many fingers. For example, if both sides of the finger are fused, then multiple surgeries might be needed. This might put the individual at a neurovascular risk. Thus step by step surgical release is made in the digits. The surgery is completed before the school age as motor skills are required.
Before the Procedure:
Before the surgical procedure, the parents are advised to properly bathe the kid, particularly the hands and groin area.
During the Procedure:
The de-syndactyly procedure usually involves one side of the finger at a time. This is done to prevent the decrease in the blood flow in that area in case any of the blood vessels are injured during the procedure. The surgery is carried out keeping in mind the type and location of the syndactyly. The surgical release is usually carried out by dividing the fingers and covering the wound with a flap with good vascularization. The commonly used flap is a rectangular dorsal flap. There are various designs that are used for this flap, such as triangular, rectangular, omega, and multi-lobed. Other flaps used are interdigitating fasciocutaneous flaps and full-thickness skin grafts.
The flap is inserted with a slope in the dorsal-to-volar (back of the hand to the palm region) region. The distal end of the flap ends in the finger that is closer to it. In the case of the involvement of the fingernail, the flap is divided vertically. Broad fingernails should be reduced to normal size. After the removal of the bone, the fasciocutaneous flaps should be applied to the exposed bone for proper coverage. The local interdigitating flaps should be designed such as to reduce the need for skin grafts. Full-thickness skin grafts are applied in places where fasciocutaneous flats cannot be applied. Skin grafts are required in most cases of syndactyly except incomplete simple syndactyly between the thumb and the index finger. Different techniques, such as double-opposing Z-plasty or a four-flap Z-plasty, can be done in cases with incomplete simple syndactyly, which do not need skin grafts. The four-flap Z-plasty is preferred more as compared to single Z-plasty as it gives good length and shape. The dorsal flaps are used to cover the defect in the palm region to cover the lateral finger defects. The location of the incision and its pattern is also determined. The most preferred pattern is zigzag. The Cronin technique uses matched zigzag incisions on the flexor and dorsal surfaces. The modified Cronin technique uses dorsal and volar triangular flaps with oblique zigzag incisions.
As compared to split-thickness grafts, full-thickness grafts are usually preferred as they grow as the patient grows and are less likely to contract over time. The common site for full-thickness graft is a lateral inguinal region. The skin is removed in the shape of an ellipse, closing the donor site fully. The rate of infection is usually low with this graft. The area heals properly without much scarring. In the case of complex syndactyly, a groin flap can be used for covering the interdigital area. A non-pigmented skin graft can also be taken from the plantar surface of the foot. The prepuce is another source of graft, as it tends to hyper pigment with time.
After the Procedure:
After the procedure, a dressing is applied at the surgical site. A good amount of antibiotic ointment and a non-sticky dressing over the grafted skin is applied over the incision. The hand is wrapped with a padded long-arm dressing with a splint. The graft donor site is closed with absorbable sutures. The donor site dressing should be removed three days post-surgery and thoroughly cleaned with soap water during the bath. The long-arm dressing with the splint is removed after two to three weeks after proper inspection by the doctor. If the patient is uncomfortable with the dressing, it can be removed, and the caretakers are advised to take care of the wound daily. The wound area is cleaned with a cotton swab dabbed with antibiotic ointment. The surgical site is cleaned with two by two cotton gauze, reinforced with five-centimeter gauze. Stockinettes are applied on the arms and secured with the shirt to prevent the dressing from coming off. Scar management is done six weeks post-surgery.
What Are the Complications of De-syndactyly Surgery?
The complication of de-syndactyly surgery includes the following:
Loss of blood supply in the finger.
Recurrence of syndactyly.
Complications associated with different skin grafts.
Tightening of the muscles, ligaments, tendons, or skin.
Simple syndactyly surgery leads to independent, freely mobile fingers by significantly improving the hand appearance. In comparison, complex syndactyly surgery is associated with mobility loss due to the high risk of skin tightening and scarring. The parents are instructed to keep the stockinette in place to prevent the child from contaminating the area. Scar tissue formation can be avoided with skin massage or silicone gel sheets.