Back injury research: a common thread.

Attempts to reduce back injuries associated with manual lifting and handling have resulted in the development of several lifting techniques which might be described as mechanical, hip-flex, kinetic, dynamic and natural. Examination of the literature indicates that each has merits and no single method is suitable for all persons in all situations. This paper takes an objective look at the principles involved in an attempt to expose some common threads, thereby permitting a more realistic evaluation of the applicability of each method.