I bought the 1st Edition of this book several years ago. After reading about 20 or 25 pages I had found not just omissions, but actual errors in this book. I would definitely rate the 1st edition as only 1 star (or zero if possible). I haven't read (and never will) the second ed, but if I were you, knowing that the 1st ed had outright errors in it, I would make sure you see it in a library or bookstore and look through it thoroughly before committing to buy this one!
BTW, Pocketpedia and Physical Medicine and Rehabilitation Secrets are both Excellent books. Buy them instead, or get Physical Medicine and Rehabilitation Board Review for a more comprehensive but less portable review. Best Wishes!