Behavioral recovery after a spinal deafferentation injury in monkeys does not correlate with corticospinal sprouting

A long held view in the spinal cord injury field is that corticospinal terminal sprouting is needed for new connections to form that then mediate behavioral recovery. The inference is that more extensive sprouting predicts greater recovery, though there is little evidence to support this. Here we compare behavioral data from two established deafferentation injury models in monkeys, to provide a clear example that sprouting does not track with behavioral recovery.