Operative techniques

Operative techniques for correction of syndactyly need to address many potential problems: (1,2)

• options for recreation of web space include:
  • dorsal rectangular flap of thinner, more mobile skin transposed into palmar defect:
    • commonly used
    • trapezoidal in shape
    • designed by measuring the length of neighbouring commissures and adding a few millimetres to this length to allow for minor adjustments
    • centred on the middle of the interdigital space of the syndactylised digits
    • typically 8-9 mm in width at base and narrower at tip
  • modification of this design with:
    • dorsal triangular skin flaps to aid in resurfacing of dorsal sides of digits
    • making the tip of the rectangular flap oblique, diamond shaped or 'M'-shaped to fit into a 'Y'-shaped defect volarly
    • rectangular flaps from the volar side
  • transposition of opposing palmar and dorsal inverted-V triangular skin flaps
  • island flap method eg using a V-Y advancement of an island of dorsal skin into the commissure
  • dorsal four flap z-plasty
  • jumping man flap
  • historically as uniformly prone to poor results, simple division of skin or free skin grafting alone
• separation of digits:
  • classically, achieved by interdigitating triangular skin flaps from the volar and dorsal surfaces of the digit:
    • typically, 60 degree angles at the tips of flaps with none crossing perpendicular to flexion creases
    • obliquity of scars reduces the risk of flexion contracture
    • usually not enough skin to resurface the sides of both digits and small full thickness skin grafts are placed into the gaps; grafts are usually harvested from the groin and inset under minimal tension; other options for donor sites include the medial malleolar area of the foot
  • other described options include:
    • simple longitudinal separation; prone to poor results but may be useful in the unusual situation of Apert's Syndrome where symphalangism prevents flexion contractures
    • tissue expansion dorsally to obviate the need for skin grafting
    • bone distraction away from the meridian of the web to create more skin prior to division
    • pedicled distant flaps for skin cover eg groin flap
• recreation of nail fold: Buck-Gramcko technique with a flap of triangular pulp folded back onto the ipsilateral margin of the nail

Reference

1. Vekris MD, Lykissas MG, Soucacos PN, Korompilias AV, Beris AE. Congenital syndactyly: outcome of surgical treatment in 131 webs. Tech Hand Up Extrem Surg. 2010 Mar;14(1):2-7.
2. Lumenta DB, Kitzinger HB, Beck H, Frey M. Long-term outcomes of web creep, scar quality, and function after simple syndactyly surgical treatment. J Hand Surg Am. 2010 Aug;35(8):1323-9.