History of the Study of Locomotion

Post World War II

Verne Thompson Inman (1905-1980)

Verne Inman was an exceptional person in an important position at a pivotal time. Not only did his studies of the biomechanics of locomotion establish the field, they are classics in the application of engineering expertise to clinical problems through basic research.

He was born in San Jose, California in 1905 and attended the University of California at Berkeley as an undergraduate. While in medical school, he worked as an assistant in anatomy and earned an M.A. degree for studies of electrical stimulation of cutaneous nerves in humans.

Upon completing his medical studies he commenced a Ph.D in Anatomy. His specific interest focused on nerve conduction in the giant axon of invertebrates, which fitted well with the department's emphasis on physiology. While the electrical equipment he needed to conduct this project was available from his prior research, he was unable to obtain suitable specimens and had to abandon the project. Although disappointed, he chose to study the differential development of the human fetal cranium, and with that work obtained his Ph.D in 1934, being the last doctoral student at Berkeley or San Francisco to offer a thesis in gross anatomy. An internship and residency in orthopaedics followed, and by 1940, Verne Inman had become a clinical instructor in orthopaedic surgery as well as an instructor in anatomy, and had published articles on the anatomy and pathology of the intervertebral disc.

As World War II neared its end, he published an important paper on the biomechanics of the shoulder. Shortly thereafter, at the urging of the National Research Council, the Surgeon General's Office (and, later on, the Veteran's Administration) he began developing a research program directed at the physical problems of the tens of thousands of amputees who were returning from the war. The upper-extremity research program, which might have been a logical extension of his shoulder research, was established in Southern California to be near the aerospace industry which had the flexible cables necessary for such research. The lower-extremity research program, in which he was one of two major leaders, began in Northern California as the Biomechanics Laboratory. It was located on both the Berkeley campus in collaboration with faculty from the Department of Engineering, and on the San Francisco campus, initially using space in the Department of Anatomy.

It was soon evident that basic research was needed if intelligent design changes were to be made in the unsatisfactory prosthetic devices of the time. Here, then, was the opportunity for him to integrate his interests in mechanical and electronic devices, since
elucidation of the basic biomechanics of locomotion required study of not only the dynamics of body motion, but also analysis of the phasic electrical activity of the appropriate muscles. As the scope of the project broadened to include problems with muscle physiology, pain, and skin, the Biomechanics Laboratory became the first departmentally based interdisciplinary research group on the San Francisco campus. The collaboration between the basic sciences and the Department of Orthopaedic Surgery established high standards for such worthwhile interactions. The goals of basic research as well as their clinical applications were met by the diverse group of specialists who participated in the project. International fame and major publications in the areas of human locomotion, the mechanisms of pain, and rational prosthetic design were the result.

Verne's role was often to reframe a question, simplify the approach to a problem, or outline a general research strategy, and then step aside to let the specialist, researcher, or student proceed. He had a consuming curiosity and thoroughly enjoyed the challenge of problems while maintaining a resolute skepticism when confronted with superficial or pat answers. He saw
issues broadly, and sought solutions in unexpected sites. In one instance, for example, his dissection of a bear's foot provided insight into the anatomy of the human plantigrade foot. The elegance of nature revealed by his research gave Verne inordinate pleasure. He also enjoyed working skillfully with his hands; it was not uncommon to find him in the laboratory or shop on weekends or late at night, constructing a beautifully detailed working model with which to demonstrate some fundamental principle of human biomechanics.

Retirement in 1973 did not change Verne's approach to life. His time and energies simply turned to the problems of the family "ranch" in San Jose. There, he designed a new means of clipping large hedges, and he cultivated unusual plants and fruit trees while remaining a consultant to the Biomechanics Laboratory. He met with his editorial staff to finalize the manuscript of his definitive treatise Human Locomotion just three weeks before his death after a brief illness at age 74.

Though published over 40 years ago, this list of gait determinants still guides many researchers and clinicians' thinking about human gait. The authors began by assuming that a gait pattern is most efficient when it minimizes vertical and lateral excursions in the body's center of gravity (COG). They identified those features of the movement pattern that miminize these COG excursions. They suggested that these features determine whether a movement pattern is normal or pathological.

Inman, VT, Ralston, HJ, and Todd, Frank (1981).  Human Walking.Williams and Wilkins, Baltimore/London.
Saunders, J.B., Inman, V.T., & Eberhart, H.D. (1953). The major determinants in normal and pathological gait. Journal of Bone and Joint Surgery, 35A, 543-558.
Inman, V.T. (1966). Human locomotion. Canadian Medical Association Journal, 94, 1047.
Mann, Roger, and Verne T. Inman 1964. Phasic activity of intrinsic muscles of the foot. Journal of Bone and Joint Surgery

Biomechanics Laboratory (1) Dr. Verne Inman (center), Professor Howard Eberhart (right), and __ Henderson (in wheelchair) in the Biomechanics Laboratory at Berkely.

Howard Davis Eberhart (1906-1993)

Civil Engineer from Lima, Ohio, who studied the University of Oregon at Eugene. His expertise in structures led him into reearch aimed at improving concrete runways to withstand the stresses from heavy bombers in World War II. In 1944 during a nighttime test at Hamilton Field in Marin County, California, a heavy truck simulating the weight of a bomber rolled over his leg, requiring a below-knee amputation. The surgeon was Verne Inman, Professor of Orthopedic Surgery at the University of California Medical Center in San Francisco (now UCSF), who had just been asked to set up a National Research Council Advisory Committee on Artificial Limbs for the large numbers of limbless servicemen. Their partnership was to continue for the next thirty years. Together with Chuck Radcliffe, they established the Prosthetic Device Research Project in the Berkely Department of Engineering which was to perform fundamental studies of the mechanics of human locomotion and prosthetics. In 1957 this became the Biomechanics Laboratory and was moved to the Medical School in San Francisco, returned to Berkely 1967-1974, when the Veterans Administration funding ceased.

Prof. Eberhart was admitted to the National Academy of Engineering in 1977 "for pioneering studies of human locomotion, application of structural engineering to prosthetic devices, and leadership of interdisciplinary engineering research".

Henry Ralston

Ralston HJ (1958) Energy-speed relation and optimal speed during level walking. Int Z angew. Physiol. einschl. Arbeitsphysiol. 17 (8): 273-288.

John B. De C. M. Saunders (1903-1991)Portrait of John B. De C. M. Saunders (1903-1991)

John Bertrand deCusance Morant Saunders was born in Grahamstown, South Africa, the son of a British army surgeon of Scottish ancestry. After pre-medical studies at St. Andrew's College and at Rhodes University College in South Africa, he went to the University of Edinburgh for his MB ChB, then taught anatomy and physiology at his alma mater while he qualified for his FRCS in 1930.

Saunders came to the University of California in 1931 as an anatomy professor, was chair of the department from 1938 to 1956. He conducted research with LeRoy C. Abbott of the Department of Orthopedic Surgery, and Verne T. Inman of the
Biomechanics Laboratory. With them and other colleagues he studied the normal and diseased spinal column, nerve injury and
regeneration, the mechanics of the joints of the upper and lower limbs, and the nature of normal and pathological gait. He published studies on congenital abnormalities of the duodenum, and on the development of the genitourinary tract. Later, he made important observations on the formation of the ventricles and the aorta.

On the occasion of the 400th anniversary of the publication of the great anatomical work, De Humani Corporis Fabrici, by Andreas Vesalius in 1543, Saunders published a paper with Leroy Crummer on Loys Vasse, an contemporary of Vesalius. He continued to write several papers on aspects of the life and times of Vesalius and continued to write and publish on medical history until his death at age eighty-eight.

Saunders, J.B., Inman, V.T., & Eberhart, H.D. (1953). The major determinants in normal and pathological gait. Journal of Bone and Joint Surgery, 35A, 543-558.

Frank Todd

Boris Bresler (1919-2000)

Born in Manchuria, Bresler was part of the Russian Jewish community that emigrated to China prior to the Russian Revolution. As part of the team investigating prosthetics at Berkeley, he revived the work of Braune and Fischer in analyzing the dynamics of locomotion, calculating the moments and powers at the main joints.

Energy and power in the legs of above-knee amputees during normal level walking, B. Bresler, C,W. Radcliffe, and F.R. Berry. Berkeley, Lower-Extremity Amputee Research-Project, Institute of Engineering Research, University of California, 1957. Radcliffe, C. W. (Charles W.) Technical report (University of California, Berkeley. Biomechanics Laboratory); 31.
Bresler, B. and Frankel, J. (1950). The forces and moments in the leg during level walking. Transactions of the ASME: 27-36.

Nikolai Bernstein (1896—1966)

Many of the key issues in modern day movement coordination were formulated by the Russian neurophysiologist and
movement pioneer Nikolai Bernstein during the first half of the past century. Some of these issues include the degrees of
freedom problem, motor equivalence, and non-univocality of motor commands and peripheral effects. Bernstein's work is so
important as many theoretical "streams" lay claim to his insights and work.

Due to political reasons, his1947 book, Coordination and Regulation of Movements, was not translated until 1967. Bernstein challenged the view held in McGraw's and Gesell's time of a hierarchical system within the body whereby commands for movement were issued by the brain.  He posited that performance of any kind of movement results from an infinite variety of possible combinations, or degrees of freedom, of neuromuscular and skeletal elements.  The system should, therefore, be considered as self-organizing, with body elements coordinated, or assembled, in response to specific tasks.  Motor development was dependent not on brain maturation, but adaptations to constraints of the body (changes in the growing infant's body mass and proportions) and to exogenous conditions (gravity, surface, specific tasks to be performed).

The analysis of coordinated movements became the study of biomechanics.  This term, coined by Bernstein, describes the application of mechanical principles and methods to biological systems.  These involve two areas: kinematics, or time-space forms of movement such as muscle activation and joint movement; and dynamics, the physical causes of movements such as inertial or centripetal forces, power (acceleration) and torque (rotation).  The methods of analysis include electrographic recordings of joint angular velocity and muscle activation, and free body diagrams showing body segments and forces acting on them

Wilfrid Taylor Dempster

Dempster examined the cadavers of eight elderly men at the University of Michigan, and
estimated the volume, mass, density, center of mass and mass moments of inertia for the body
The limb segments were separated at each of the primary joints (after being exe to mid-range and
frozen) and the trunk divided into units corresponding to the neck, shoulders, thorax and
abdominopelvis. Each segment was then weighed, the center of mass was estimated with a
specially designed balance plate, two different mass moments of inertia (around a transverse axis
through the center of mass and around a parallel axis through the center of the proximal joint)
was estimated from the period of oscillation and the volume was estimated by the principle of

Space requirements of the seated operator. Technical Report USAF,
WADC TR-55-159 (AD 87 892), Wright Air Development Center, Wright-Patterson Air Force Base, Ohio, 1955.

Wilfrid Taylor Dempster. The anthropometry of body action. Annals New York Academy of Sciences, 63:559{585, 1956.

Rudolfs Drillis and Renato Contini.

The initial interest of Drillis and Contini was the design of improved prosthetic devices, but since
this require good estimates of the mass, center of mass and mass moments of inertia of the
segments, 20 young living male subjects were carefully examined. Body segment volumes were
determined both with a method similar to the one used by, e.g., Cleveland and Dempster
(hydrostatic weighing) and by a segment zone method (incremental hydrostatic weighing). The
segment zone method is like hydrostatic weighing, but the measurements are performed
repeatedly as the segment is lowered into the water in small equidistant steps. This method
makes it possible to estimate the volume of each of the slices formed by the stepwise immersion.
The center of mass was assumed to be coincident with the mid-volume, which made an
estimation of the center of mass possible. The mass of the segments were estimated with a highly
sensitive balance plate resembling the one in Figure 1. The study resembles the one performed
by Bernstein, but are concentrated on the body segment parameters of young men and are
considered to be well thought out and carefully executed.

Rudolfs Drillis and Renato Contini. Body segment parameters. Technical Report 1166-
03, New York University, School of Engineering and Science, Research Division, New York under contract
with Office of Vocational Rehabilitation, Department of Health, Education and Welfare, September 1966.

Charles E. Clauser

Clauser, and coworkers, performed a study designed to supplement the existing knowledge of the
mass, volume and center of mass of body segments and to permit a more accurate estimation of
these measurements from anthropometric dimensions. The study was based on 13 preserved
male cadavers, which each were dissected into 14 body segments. The mass, volume and center
of mass were measured for each segment with methods resembling the ones used by both Braune
and Fisher and by Dempster. Anthropometric measurements like the length, circumference and
breadth or depth of each body segment were also measured and a series of regression equations
estimating the body segment parameters based on anthropometric measurements were defined. It
was concluded that the anthropometry of the body and regression equations effectively can be
used to estimate the mass and center of mass of body segments, under the assumption that all
individuals essentially have the same body proportions. This can, however, not be assumed in
general and will thus lead to major errors in estimates for those individuals, or groups, that differ
significantly from the average of the group of subjects from which the regression equations are
derived. The assumption, used in many earlier studies, that the center of mass and center of
volume of body segments are nearly coincident was also investigated. It was concluded, that the
two centers not are coincident, but that the center of volume of a segment generally are less that
two to three centimeters proximal to the center of mass.

Charles E. Clauser, John T. McConville, and J. W. Young. Weight, volume, and center of
mass of segments of the human body. Technical Report AMRL-TR-69-70 (AD-710 622), Aerospace Medical
Research Laboratory, Aerospace Medical Division, Air Force Systems Command, Wright-Patterson Air Force
Base, Ohio, August 1969.

RF Chandler

Chandler, and coworkers, performed a study to investigate, and supplement the existing
knowledge about, the mass distribution characteristics of the human body as described by the
principal mass moments of inertia. The mass, volume, center of mass and principal mass
moments of inertia were estimated for the 14 segments from each of six frozen preserved adult
male cadavers and, excluding the volume, for each of the entire cadavers. Anthropometric
measurements were also obtained both for the entire cadavers and for each of the segments. The
methods and procedures used in this study for obtaining a total of 116 anthropometric
measurements of each cadaver, segmentation of the cadavers and estimation of mass, volume
and center of mass to a large extend resemble the ones used in [Clauser et al., 1969]. In order to
estimate the principal mass moments of inertia each segment was fixed in a segment holder of
Styrofoam of minimal size in order to minimize the potential errors introduced by the holder.
Each segment holder was then used to establish an external Cartesian coordinate system, fixed
with respect to the otherwise geometrically irregular body segment.
Each segment, in its segment holder, was then swung around six axes as a pendulum and the
period of oscillation around each axis was measured at least twice, each for a period of 50 swing
cycles of the \pendulum”. Based on these measurements, corrected with similar measurements
performed on the empty segment holder, and a precise measurement of the local gravitational
constant, the mass moment of inertia of the segment around each of the six axes were calculated.

Based on these calculations the three principal mass moments of inertia of each body segment
were estimated.
Some of the results of this study of cadavers were compared to those obtained, by Santschi and
coworkers, on living subjects and it was concluded that a sat- is factory level of agreement exists.
It was also concluded that the principal mass moments of inertia of body segments correlates
well with total body mass and (especially) with segment volume.

R. F. Chandler, C. E. Clauser, J. T. McConville, H. M. Reynolds, and J. W. Young.
Investigation of inertial properties of the human body. Technical Report DOT HS-801 430, Aerospace Medical
Research Laboratory, Wright-Patterson Air Force Base, OH, March 1975.

Larry W. Lamoreux  b. 1936

Experimental Kinematics of Human Walking, Ph.D. Thesis, University of California at Berkeley, 1970

Exoskeletal goniometer examination of lower limb motions during walking at different speeds.

The pelvic frame was attached with eight contacts, over the ASISs, iliac crests, pubis, sacrum, and ischial tuberosities.  The hip joint was an Euler sequence - flexion, abduction, axial rotation - that was aligned to the anatomic hip joint.  Knee and ankle joints were measured with parallelogram linkages that did not depend on precise alignment with the anatomic axes for accurate angle measurements.  Measurements were conducted on a treadmill to allow averaging of multiple cycles.  Pelvic motions, both linear and angular, were recorded by parallel strings attached to displacement transducers mounted to the treadmill frame.  Potentiometers provided electrical outputs which were recorded onto an FM modulated instrumentation tape recorder.  Replay from the recorder was converted to digital format on a DEC PDP-7 computer (18 bit).

Lamoreux, LW, 1971, Kinematic Measurements in the Study of Human Walking, Bul. Prosth. Res. BPR 10-15

Charles, Robert, Jean & Pierre Ducroquet

Charles Ducroquet, a Paris physician, spent the better part of his life studying limping. He took films in the open air, processing them himself, while the patient waited. Later, he inspired his sons to continue the work, culminating in the book "Walking and Limping: A study of Normal and Pathological Walking" (JB Lipincott Co. 1965).
The Glass Cage

Several novel tools are described in the book, including the "glass cage" and "simplified glass cage".

The orthopedist is encouraged to observe the gait in 3D and use a hand-held sighting goniometer and "claudico-oscillometer" to quantify pathological angles.

Observing gait in 3D with the simplfied Glass Cage

Marcel Saussez

In the final chapter of the above Ducroquet book, Marcel Saussez (a Brussels physician) describes his experiments with recording "luminous curves".
Saussez equipment

Walking and limping; a study of normal and pathological walking [Original: La marche et les Bioteries] Robert Ducroquet, Jean Ducroquet [and] Pierre Ducroquet, with the collaboration of Marcel Saussez. Illustrated by Marcel Dudouet. Pref. by Emanuel Kaplan.Translated by William S. Hunter and Jep Hunter. Philadelphia, Lippincott [1968]

John V. Basmajian (1921-2008)

Back pain is just a tension headache that has slipped down the back

Canadian anatomist, earned his medical degree from the University of Toronto in 1945 where he then he joined the staff and achieved the rank of Professor. Along the way he also pursued clinical research at the Hospital for Sick Children and McMaster Univ. His work with polio patients using electromyography to study muscle control mechanisms revolutionized the use of electronic and mechanical devices for people with neurological and orthopedic impairments. Introduced fine-wire electrodes that were more comfortable than needles and could be used longer. In the 1960s, he used electromyographic biofeedback to train patients to regain control muscle functions that were thought to be permanently lost. It is because of these efforts that he is referred to as the "Father of EMG Biofeedback Therapy". Founded International Society of Electrophysiological Kinesiology, ISEK, in 1965 to create standards for EMG usage and reporting. This society continues today as a multidisciplinary organization dedicated to studying human movement and the neuromuscular system.

Dr. John Basmajian received his MD degree in 1945 from the University of Toronto. He intended to specialize in Orthopaedic Surgery but for health reasons specialized in Anatomy.

Muscles Alive was the first collection of studies that used technology to study muscle behavior during voluntary activity. This book sparked the imaginations of countless students and practitioners of Health Sciences, Medicine, and Engineering to explore the workings of muscles and, as he put it "their functions revealed by Electromyography".  His passion and tireless curiosity for understanding human movement in the normal and dysfunctional states brought forth more than two dozen books and nearly 400 scientific papers. He was awarded the highest civilian honor as an Officer of the Order of Canada (OC).

Basmajian, J. V. (1978).  Muscles alive:  Their functions revealed by electromyography.  4th ed  Baltimore:  Williams and Wilkins.
On psychological aspects of backaches, Time 14 Jul 80

Wolf SL (1997) The first Basmajian lecture. Reflections on John V. Basmajian: Anatomist, Electromyographer, Scientist.J Electromyogr Kinesiol. 7(4):213-219.