Grasping objects by former amputees: The visuo-motor control of allografted hands.

PURPOSE: Hand allograft has recently emerged as a therapeutic option for upper limb amputees. Functional neuroimaging studies have progressively revealed sensorimotor cortices plasticity following both amputation and transplantation. The purpose of our study was to assess and characterize the functional recovery of the visuo-motor control of prehension in bilateral hand transplanted patients. METHODS: Using kinematics recordings, we characterized the performance of prehension with or without visual feed-back for object of different position and size, in five bilateral hand allograft recipients and age-matched control subjects. Both hands were assessed, separately. RESULTS: Despite an overall slower execution, allografted patients succeeded in grasping for more than 90% of the trials. They exhibited a preserved hand grip scaling according to object size, and preserved prehension performances when tested without visual feedback. These findings highlight the allograft recipients' abilities to produce an effective motor program, and a good proprioceptive-dependent online control. Nevertheless, the maximum grip aperture was reduced and delayed, the coupling between Transport and Grasp components was altered, and the final phase of the movement was lengthened. CONCLUSION: Hand allotransplantation can offer recipients a good recovery of the visuo-motor control of prehension, with slight impairments likely attributable to peripheral neuro-orthopedic limitations.

Bilateral hand transplantation: Functional benefits assessment in five patients with a mean follow-up of 7.6 years (range 4-13 years).

Between January 2000 and July 2009, five adults who had suffered bilateral traumatic below-elbow amputations, received bilateral hand-forearm allografts performed by the Lyon team. We report the functional benefits achieved over a mean follow-up period of 7.6 years (range 4-13 years), up to December 31st, 2013. Clinical measurement is hampered by the lack of specific validated assessment tools, obliging us to use non-specific standardized evaluation means. Our assessment shows that the restoration of motion, strength, and sensibility are fair. Functional results (Carroll upper extremity function test, 400-point test, Activities of daily living) are good, as well as quality of life evaluation (RAND-36). Subjective and overall results explored with questionnaires - Disabilities of the Arm Shoulder and Hand (DASH), Hand Transplantation Score System (HTSS), are very good. Improvement was seen to continue during the first three years, and then tend to become stable. Continued efforts should be directed at designing comprehensive, condition-specific, reliable outcome measurement tools. Continuous monitoring and evaluation of patients is required to assess the long-term risk-benefit balance.