Microvascular “on-top-plasty”: An Alternative for Thumb Reconstruction in Constriction Band Syndrome

Constriction band syndrome affecting the hand and importantly the thumb may require reconstruction to improve function. This case report presents a patient with auto-amputation through the proximal phalanx of the middle, index, and thumb. Microvascular reconstruction was used to perform an on-top-plasty with the remaining index finger to the thumb. The case also involved skin graft coverage, venous grafting, and tendon reconstruction. The patient presents with 12 months follow up after index procedure and 3 months after revision. She has the ability to grasp large objects. Sensation remains present in pulp of new thumb. Cosmesis subjectively improved per patient’s family and physician. Strength continued to improve and reached 2 Kg of grip strength by 12 months. Microvascular on-top-plasty is a possible option for improving function in constriction hand syndrome affecting multiple digits.