Describe the process that occurs when a person is involved in an accident in Terms of cell injury

Describe the process that occurs when a person is involved in an accident in terms of cell injury.Which particular cells will be affected .Explain the reasons that will account for the loss of function of the legs even after a week. Can his situation be reversed as his legs become slimmer and is unable to walk , while his arms become bigger and functional .What should be done to reverse his situation if possible.

PS:Should be answered in relation to cell atrophy, hypertrophy , metaplasia ,etc as studied in cell injury