Adaptation of the cortical motor network following heterotopic hand replantation probed by fMRI and effective connectivity analysis

In this functional magnetic resonance imaging study, we examined changes in cortical activation and connectivity in two patients following unilateral heterotopic replantation of the hand and distal forearm to the upper arm for proximal forearm tumours. The patients and a group of healthy controls performed visually paced hand movements with their left, right, or both hands. Effective connectivity during this task was assessed among a bilateral motor network -comprising primary motor cortex (M1), lateral premotor cortex (PMC), and supplementary motor area (SMA)- using dynamic causal modelling. When moving the nor…