Cortical Integration of the Free Transferred Toes in Posttraumatic Hand Reconstruction

Introduction: Reconstruction of the thumb and complex hand mutilations with fingers amputation are best solved by microsurgical transferring the toes. Transferred toes-to-hand will be innervated much better than they were in the donor site, performance explained by both the higher number of nerve fibers in the digital nerves of the hand comparative to the toes and cortex plasticity. Suite phenomena occurring in cortical integration of the microsurgical transferred toes-to-hand is comparable to that following the digital nerve repair or replantation.

Methodology and Material: We performed 25 transferred toe-to-hand cases operated between 1998 and 2013 in which 8 great toe transfers (2 wraparound), 12 transfers of second toe and 5 transfers of second and third toes. Time interval from injury to reconstruction was 5-19 months for accidents and respectively 9 years for single case of amputation in childhood. Indications of toes transfer were based on the level of amputation after Merle. Assessment of the toe-to-hand cortical reintegration was made according to Medical Research Council for motor recovery (M0-M5) and sensitive (S0-S4) at every 6 months, 1 year, 2 and 3 years. 12 patients were followed-up at longer intervals of time (5-11 years) and to assess recovery of sensitivity we conducted qualitative and quantitative tests (Semmes - Weinstein, Dellon test).

Results: After evaluation of the 2PD, patients interval results were: 6-8mm (4), 9-12 mm (15) 13-16 mm (4) and in 2 patients > 16 mm. Functional reintegration of the thumb reconstructed by wraparound process (Morison technique) offers the best cosmetic result (6-8 mm), because the reconstructed thumb has dimensions very close to those of the normal thumb. In thumb reconstruction, functional recovery after Kapandji scale was 7-8 and in wraparound technique was 9-10. Despite the unsightly appearance, motor recovery of the toe-to-hand offered patients the possibilities of use of hand mutilated.

Conclusions: Reconstruction of the mutilated hand by toe-to-hand transfer is a technique that provides better result sustained by motor and sensory physiotherapy. Reinervated toe’s pulp by digital nerve fibers of the hand can achieve a smoothness tactile perception.