A combination (2290) of an annular rotary knife blade (2300) and blade housing assembly (2400) for a power operated dermatome (2000). The rotary knife blade includes an inner wall (2310) defining an interior region (2301) and including a lower tissue-directing surface (2370) adjacent a cutting edge (2360) and a radially recessed upper portion (2380). The blade housing assembly includes a blade housing (2410) having a first end (2412) and an axially spaced apart second end (2414) and an inner wall (2416) and a radially spaced apart outer wall (2418). The blade housing includes a blade housing cover (2450) extending from the inner wall into the blade interior region. The blade housing cover includes a shield (2470) extending along the recessed upper portion of the rotary knife blade inner wall and having an inner surface (2472) adjacent and continuing the lower tissue-directing surface of the rotary knife blade inner wall.