Properties of body segments based on size and weight

Values are presented for body constants based on a study of nine male white cadavers of normal appearance and average build. The limb data are supplemented by a further analysis of 11 upper and 41 lower limbs. Techniques used in the study form standard procedures that can be duplicated by subsequent workers. Each cadaver was measured, weighed, and somatotyped. Joints were placed in the midposition of the movement range and the body was frozen rigid. Joint angles were bisected in a systematic dismemberment procedure to produce unit segments. These segment lengths were weighed, measured for linear link dimensions, and analysed for segment volumes. The segment centers of mass were located relative to link end points as well as in relation to anatomical landmarks. Finally, each segment was dissected into its component parts and these were weighed. The specific gravity of each body part was calculated separately. Data are expressed in mean values together with standard deviations and, where available, are correlated and evaluated with other values in the literature. Data on the relative bulk of body segments have been scarce. Until recently, the only users of information dealing with the mass and proportion of the human figure have been sculptors and graphic artists. These people usually met their needs through canons of proportions and a trained perception rather than by actual measurement. There are no substitutes though for good empirical data when critical work on body mechanics or accurate analyses of human locomotion are attempted. During the past decade or so, the need for such information has been recognized specifically in designing prosthetic and orthotic devices for the limbs of handicapped persons, for sports analysis, for the construction of test dummies, such as those subjected to vehicular crashes, and for studies on the dynamics of body impacts in crashes and falls. The fundamental nature of data on the mass and dimensions of the body parts cannot be questioned. It is odd that even now there is such a dearth of information. The research literature up to the present contains usable body segment measurements from only 12 (or possibly 14) unpreserved and dismembered cadavers, all adult white males. A tabulation of data in an Air Force technical report (Dempster, '55a), dealing with seven specimens caAM. J. ANAT., 120: 33-54. daver by cadaver, was the first amplification of the scanty records in more than two generations. The tables on Michigan cadavers were reprinted by Krogman and Johnston ( '63) in an abridgment of the original report; Williams and Lisner ( '62) presented their own simplifications based on the same study; Barter ('57), Duggar ( '62) and Contini, Drillis, and Bluestein ( '63) have made tallys of data from the original tabulations along with parts of the older data. None of these studies gave any attention to the procedural distinctions between workers who had procured original data; one even grouped volumes and masses indiscriminately as masses. The Michigan data, however, have not been summarized nor evaluated up to this time. Since the procedures and, especially, the limiting conditions incidental to the gathering of body-segment data, have not been commented on critically since Braune and Fischer (1889), a comprehensive discussion of the entire problem at this point should help further work in this important area. 1 Supported in part by research grants from the Public Health Service National Institutes of Health (GM-07741-06). and from the office of Vocational Rehabilitation (RD-216 60-C), wlth support a dozen vears earlier' from a research contract with the Anthropometric Unit of the Wright Air Development Center Wright-Patterson Air Force Base, Dayton, Ohio (AF 18 (600)-43 Project no. 7414).