<qa>  What is the effect of FES bike therapy on bone mineral density and psychological well-being?The inability to walk due to spinal cord dysfunction has profound effects on patients, both physiologically and psychologically. Complications associated with walking upright include loss of muscle mass from atrophy, reduction in bone mineral density osteoporosis, compromised cardiovascular endurance, loss of sense of well-being, etc. Functional Electrical Stimulation FES of the lower extremities has been found to reverse many of these complications. We propose to examine the use of FES in children who have suffered from spinal cord injury SCI. We plan to examine the effect of FES bike therapy on bone mineral density and psychological well-being. 