Purpose:
The first dorsal metacarpal artery (FDMA) flap was originally described by Fouchet in 1979 as a pedicled ‘kite’ flap to resurface the thumb, incorporating the artery, a superficial vein and a terminal branch of the superficial radial nerve. We describe a series of 6 cases of thumb reconstruction using a technique to tunnel the flap pedicle.
Methodology:
5 patients had an acquired defect of the thumb, 3 secondary to trauma, 1 neoplastic, and 1 due to infection, whilst 1 patient required a first webspace scar revision. The flap was raised in standard fashion including fascia and Hagar dilators were used to create a subcutaneous tunnel from the pulp defect to the 1st dorsal webspace, preserving the skin bridge between primary defect and first webspace. The flap was then passed through this tunnel and inset.
Results:
All flaps survived achieving primary wound healing. We assessed their range of motion using Kapandji scores, all achieving scores of 7-8 at first follow up. All patients had sensation, however 2-point discrimination was not formally assessed. One flap required a return to theatre for congestion, and was successfully re-inset after 48 hours.
Conclusion:
This technique reduces the requirement for surgical access to the volar surface of the thumb, limiting surgical incisions. This reduces wound burden and volar scarring whilst allowing for a functional and sensate thumb pulp.