At this point in time there are only limited treatment options available for spinal cord injury (SCI) paralysis (e.g. implanted stimulation devices, stem cells). They are in clinical trials, complex, invasive, ill-affordable, and quality of outcome rather unpredictable. This author had presented two alternative treatment procedures based on over five decades of fundamental research on the functioning of the spinal cord motor system in 2009, 2013 and 2015. These are non-invasive, functional, and recovery predictable. The first one uses low-dose Botulinum toxin to select paralyzed limb muscles. The second consists of transient partial denervation of the muscles. They both operate on similar principles of synaptic competitive-learning (SCL) and rewiring. They focus on the spinal motoneuron, its synaptic connectivity, and spinal cord reflexes. They are (i) induce competition among neuromuscular synapses, (ii) modify the motoneurons’ soma sizes (Size principle) and thus their excitability-inhibitability, firing properties, (iii) resize the motor units of the paralyzed muscles, and (iv) reposition the synaptic memory weights impinging on the motoneurons. Animal model treated by the second procedure shows that even in complete cord injury, the residual networks of the isolated distal cord are capable of remarkable motor restoration (see videos). This paper now explains the precise mechanisms behind the restorative rewiring (SCL) therapy.