Back Injury Prevention - According to the National Safety Council and medical research, 20% of backaches are attributed to inflammation such as arthritis, 10% are due to actual back injuries and other miscellaneous causes, and 70% result from degeneration of spinal discs. Topics discussed in this safety video include: the mechanics of the back, muscle strains, and difficult lifting situations. Runtime: 9 Min. WITH PURCHASE OF ANY ENGLISH VHS OR DVD YOU WILL RECEIVE A FREE WRITTEN MATERIAL CD-Rom. The CD-ROM of written materials may include: Leaders Guides, Questions & Answers, Manuals, and Power Points. Contents vary depending on program.