Bilaterally innervated dorsal digital flap for sensory reconstruction of digits

Providing sensory coverage in digits continues to be a challenging problem. This study reports the sensory reconstruction of digits with bilaterally innervated dorsal digital flaps and compares the results between dual- and single-innervated flaps.

Over 7 years, a retrospective study was conducted with 73 patients who had soft-tissue defect of the digit treated with the bilaterally innervated dorsal digital flap. There were 73 soft-tissue defects in 73 digits. The size of the defects ranged from 1.8 to 2.7cm in length (mean, 2.2cm) and from 1.6 to 2.2cm in width (mean, 1.9cm). The bilateral dorsal branches of the digital nerves were attached with the flap for the sensory reconstruction of digits. Reconstructive techniques included the cross-finger flap in 35 cases, the dorsal digital island flap in 24 cases, and the dorsal digital free flap in 14 cases. To objectively evaluate the efficacy of the bilaterally innervated flaps, we selected a comparison group that included 42 patients treated with the single-innervated flap.

A significant difference was found between the dual- and single-innervated flaps in two-point discrimination, pain, Tinel's sign, and patient satisfaction results. By comparison, the dual-innervated flap presented better discriminatory sensation on the flap, lower incidence of pain and Tinel's sign, and a larger degree of satisfaction than the single-innervated flap. Of the dual-innervated flap group, the mean joint motion of the donor finger was similar to that of the opposite side.

The bilaterally innervated dorsal digital flap is a reliable alternative for the sensory reconstruction of digits. Performing double neurorrhaphies can improve flap sensation and reduce digital neuroma incidence when reconstructing a soft-tissue defect associated with both transected digital nerves.