Rare Presentation of Congenital Syndactyly with Constriction Rings in 9 year old Patient
Geethika Simma, MBBS (final year)
Syndactyly is a congenital anomaly in which the fingers fail to separate into individual appendages. Congenital constriction rings are characterized by compression in the soft tissue usually involving the deep fascia that causes obstruction of lymphatics and blood vessels, and may lead to consequent gangrene or auto - amputation of parts distal to the constriction rings. We report a 9 year old with congenital deformity of both hands due to characteristic fusion of fingers, and the congenital deformity of 2,3 toes of left foot. This malformation is not matched to any known syndromic or non-syndromic syndactyly.
A 9 year old male patient complains of deformity of due to fusion of proximal interdigital skin of middle and index fingers with lack of distal phalanx in the right hand, and lack of distal phalanges of thumb, ring, and little fingers of the left hand. The malformation is not associated with any pain, but causes restricted movements and inability to write properly. The child confesses getting bullied by his peers due to his malformation and indicated that he dislikes the appearance of his hands.
The patient underwent a desyndactylization surgery when he was 11 months old to separate the fusion in the middle and index fingers of his right hand, and fusion of thumb, ring, and little fingers of the left hand. However, the malformation of the right hand recurred due to regrowth of the skin between the involved fingers, but has not gone for further review following the procedure. On examination, we observe difficulty in holding objects and writing. Peripheral pulses and perception of sensation on all limbs were normal, and not associated with tenderness. Upon passive movement of the fingers, there is differential motion indicating that no underlying bony union is present.
Examination of feet revealed constriction rings on left foot at the level of distal interphalangeal joints of his 2,3 toes. The patient has no difficulty in walking or pain as a consequence of the constriction rings.
Complete clinical and systemic evaluation reveals no association with any syndrome or underlying systemic disease. Family history is negative.
Radiographs showed no evidence of osseous union of syndactylized fingers. X-rays indicate distinct lack of distal phalanx of involved digits.
The patient had undergone skin release as a corrective procedure for syndactyly when he was 11 months old, but it was incompletely resolved. The complication was creeping of the skin towards the fingertip over time leading to restricted finger movements. To prevent recurrence of web creeping, Z-plasty with secondary skin grafting was performed to fully release the syndactyly. The constriction rings on his toes were corrected by simple surgical release of the connective tissue rings. Follow up 4 weeks following the procedure revealed acceptable movements of all digits and he was able to perform most of his daily activities. Postoperative condition was uneventful, pain was relieved and there was no scar contracture.
Constriction ring syndrome has an estimated incidence of 1 in 1,500 to 15,000 live births, and is believed to have no genetic predisposition. The pathogenesis of constriction rings can be explained by intrinsic theory which states that these deformities were the result of a "defective germ plasm", within the embryo. It is believed that the bands represented macerated sheets of epidermis and the residual of defective local tissue. Torpin described the extrinsic theory which suggested that the lesions are caused by the strangulating action of the mesodermal bands which occur due to an early rupture of the amnion. A third (theory postulated by Kino believed that congenital constrictions, amputations and acrosyndactyly are caused by intrauterine trauma during pregnancy, which disrupts blood supply to the parts of the limb distal to the constriction rings. In our particular case, the loss of distal phalanges of involved finger can be attributed to congenital intrauterine amputation. Surgical correction of a constriction ring if present after birth should aim at preventing or alleviating distal lymphedema, separation of an associated distal fusion and removal of an unsightly groove for cosmetic purposes.
Syndactyly is the failure of fingers or toes to separate during development, resulting in webbed digits. Our case represents simple incomplete syndactyly that has recurred in spite of previous surgical correction. Thus Z plasty was the preferred operative method of correction to prevent longitudinal scar contracture and web creeping.
Syndactyly with constriction ring syndrome and its complications are amenable to corrective surgery with good results. Early intervention is desirable for a successful outcome.