Phys ther 1986-walker-382-6

Research in Pathokinesiology−−What, Why, and How
Joan M Walker
PHYS THER. 1986; 66:382-386.

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Research in Pathokinesiology—What, Why, and How
JOAN M. WALKER

Key Words: Pathokinesiology, Physical therapy.

The University of Southern California Department of Phys- which is designed for clinical use. We also have documented
ical Therapy (USC-PT) is honored in being invited to present the effects of exercise under adverse climatic conditions or
a review of some of our research activities in pathokinesiology. with muscle imbalance.3-5 Measurements are needed that can
Specifically, I will address the following questions posed by be performed in the clinic without elaborate equipment or
the organizers of this symposium: 1) Why has USC-PT been extraordinary space. Refinement of testing methods will im-
conducting research in thefieldof pathokinesiology? 2) What prove the quality of data needed to quantify patient perform-
has been accomplished? 3) How was it accomplished? and 4) ance. Results of testing are used to assess the severity of the
How has this effort contributed, if it has, to the science of patient's problem and to reach decisions regarding the treat-
pathokinesiology? ment program. The percentage of error of the measurements
Many individuals deserve credit for providing the impetus, used must be established so that changes in results on repeated
inspiration, and opportunity to conduct research on normal tests can be considered in the proper perspective. Adams (N.
and abnormal movement. I recognize Dr. Helen Hislop, J. Adams, unpublished data, March 1976) and other
Chairman of USC-PT and author of the pivotal paper "The researchers6-19 have accomplished this to some degree for gait
Not-So-Impossible Dream"1 that today retains its relevance. and for energy studies; these studies are still in progress.
As presenter, I am simply a voice for the many who have Data in these areas have contributed to the establishment
contributed to these research efforts. The USC-PT effort has of more realistic goals for the rehabilitation of patient groups,
been undertaken in cooperation with personnel from the local such as those with spinal traumas, myelodysplasia, cerebral
area, particularly from Rancho Los Amigos Medical Center, palsy, hemiplegia, amputations, and fractures.13-15 The exer-
such as Dr. J. Perry, who is also a member of the USC-PT tion requirements of activities such as crutch gaits in patients
faculty. Drs. R. Waters, J. Hackney, D. McNeal, and B. with spinal traumas, fractures, or amputations have been
Bowman have assisted with space, equipment, and financial defined more clearly.14,16,20-23 The determination of endurance
support. limits for particular patient groups now allows a realistic
We have taken a pragmatic and perhaps simplistic approach estimation of the feasibility of independent living (eg, a child
to pathokinesiological research with emphasis on identifying with myelodysplasia attending a regular school) or provides a
and answering questions that will provide clinically useful rationale for the acquisition of equipment for mobility (eg,
data and a basis for the solution of clinical problems. Our an electric wheelchair).
central mission at USC has been to build a body of knowledge Without quantification of the energy cost of an activity,
that will provide a solid foundation for the profession of poor patient performance (ie, less than that expected by health
physical therapy and contribute to improved methods of care providers) may be thought to relate to inadequate moti-
health care. Before analytical studies can be performed, nor- vation. Our energy cost data clearly show that motivation
mative data are needed. alone will not allow some disabled individuals to perform
The specific aims of our research into the science of path- some routine activities on anything other than an occasional
okinesiology are as follows: 1) to develop methods to quantify basis.13,15,16,18,20-23 Eventually, the high energy demands of
human performance with emphasis on the everyday activities such activities may seriously compromise the individual's
of human motion, such as gait and similar exercise demands; health.
2) to establish baseline data for healthy individuals (eg, sex, Data regarding force, power, and work performed by both
age, race), "normative" values to which patient performance healthy subjects and patients still are incomplete; these studies
can be compared, thus, permitting clearer definitions of dis- are ongoing. Equipment for these studies is readily available
ability and the extent of deconditioning that will assist in the now, both in clinics and in laboratories of many physical
formulation of short-term and long-term goals for patients therapy education programs.
and contribute to treatment response predictability; 3) to
establish data bases for various patient groups that will permit USC-PT RESEARCH EFFORT
the definition of grades of impairment within injury or disease
groups; and 4) to compare the performances of healthy and Levels of Research
patient groups and obtain quantitative measures of disability Research is a requirement in all of our programs: the entry-
important to the assessment of treatment effectiveness, em- level master's degree program, the advanced master's degree
ployment potential, and disability pension reviews. program, and the doctoral degree program. Faculty members,
How has this effort contributed to the body of knowledge especially those in the tenure track, are expected to conduct
of pathokinesiology? We have been involved in the develop- their own research programs. Ideally, students sponsored by
ment of the means to quantify human performance; for an individual faculty member will work on a project consti-
example, the development of the Rancho Gait Analyzer,2 tuting part of that faculty member's research endeavor. Fac-
ulty members also conduct research in collaboration with
local clinicians. These collaborative efforts offer the greatest
Dr. Walker is Associate Professor, Department of Physical Therapy, Univer-
sity of Southern California, Rancho Los Amigos Medical Center, 12933 Erick- potential for conducting analytical studies on the effects of
son Ave, Bldg 30, Downey, CA 90242 (USA). specific therapeutic approaches.

382 PHYSICAL THERAPY

PATHOKINESIOLOGY

Constraints on our research in pathokinesiology that still
TABLE 1
require attention are insufficient laboratory space, equipment, Areas of University of Southern California Department of
and human expertise in the form of mechanical and electrical Physical Therapy Research in Pathokinesiology, 1979-1985
engineers and computer programmers; insufficient time, a
factor in entry-level student research; inadequate funding, Area n
including the availability of faculty members who have the Energy cost 16
ability to write grant proposals; and too few patient samples Force 15
with characteristics that are relatively homogeneous and data Gait 12
that are collectable over a reasonable time period. Increasingly Hemiplegia 12
Cardiovascular 10
restrictive medical, legal, and ethical restraints also exist; for
Anaerobic threshold 9
example, the use of muscle biopsies, roentgenograms, needle
Joint mobility 9
electromyograms, and animal studies. Electrical stimulation 9
Existing constraints to pathokinesiological research may be Pediatrics 5
lessened by remembering the important interrelationships Physical therapy education 5
between research plans, grants, and publications. These inter- Nerve stimulation 4
relationships, we believe, should enhance the successful ac- Special senses 4
quisition of funds to support additional research efforts in Miscellaneous 7
pathokinesiology and reduce the aforementioned constraints
to this research. The individual and the department as a whole
must have a research plan. Accomplishment of that plan TABLE 2
should result in the publication of research findings in a peer- Publication Sites of University of Southern California Department
reviewed journal. Such publication enhances the potential for of Physical Therapy Research Papers
future successful grant awards. Archives of Physical Medicine and Rehabilitation
Journal of Bone and Joint Surgery. American Volume
Master Plan Clinical Orthopaedics and Related Research
Medicine and Science in Sports and Exercise
Our research effort has not been directed according to any Developmental Medicine and Child Neurology
formal long-term master plan with a single theme. This is not Physical Therapy
to say that the research has been conducted without any European Journal of Applied Physiology and Occupational
direction. Rather, the effort has been directed by the identi- Physiology
fication of a clinically relevant problem out of which several Perceptual and Motor Skills
studies have developed. The completion of one study has led Circulation
often to the need to conduct further studies. Sometimes, Physiotherapy Canada
completion of a particular project is delayed because only a Journal of Applied Physiology
Journal of Orthopaedic and Sports Physical Therapy
certain number of students may work on one problem in any
Physical and Occupational Therapy in Geriatrics
one year and then with a less than desirable sample size. As a Yale Journal of Biology and Medicine
result, similar studies may be conducted over a period of two Journal of Pediatric Orthopedics
to five years to obtain an adequate sample size, to test both
sexes, or to test subjects representing different age groups.
Some examples would be the establishment of normative Areas covered in these studies are presented in Table 1. Thirty-
temporal gait characteristics; range-of-motion studies; nor- one studies examined energy cost or force-work-power abili-
mative data for two-point discrimination; the study of daily ties. Gait studies and studies on hemiplegic patients account
activities, such as the act of rising from a chair; or the day-to- for 12 each. Thirty-seven studies have been conducted to
day variability of routine clinical measurements.6-11,24-28 A examine the cardiovascular responses to exercise, to identify
major impetus to the direction of our research efforts to date the anaerobic threshold, to assess joint mobility, and to meas-
has been provided by questions addressed in grants acquired ure the effects of electrical stimulation. Fewer studies have
by the Rancho Los Amigos Medical Center (RLAMC) Path- been performed on children, nerve conduction characteristics,
okinesiology Service, and currently the RLAMC Rehabilita- physical therapy education, and the special senses. We also
tion Center, and the availability of equipment. Hislop's plan have conducted basic studies at the tissue and cellular level,
to establish a regional pathokinesiology research center that investigating spinal cord programming and aging changes with
would serve clinicians, faculty members, and students is de- and without exercise, in muscles and in joints.
layed because of the decrease in funds from major agencies. We estimate that since 1972 we have presented 67 papers
What, then, has been accomplished in research efforts at at national conferences, and we have published about 30
USC-PT? Between 1979 and 1983, about 120 studies were papers over the same time period. These papers were pub-
completed by students and faculty members. Few studies were lished in a variety of journals, which are listed in Table 2. No
conducted solely by a faculty member without student in- journal entitled Pathokinesiology yet exists! The end point of
volvement. These 120 studies involved more than 170 entry- any worthwhile research project, however small-scale, is the
level students and 25 advanced master's level students. Three presentation of the findings at meetings and, if suitable,
doctoral studies were completed during 1984. The majority submission of a paper for publication.
of these studies were descriptive or they were designed to We must address the question, has this research effort made
determine if differences existed between various groups. a major contribution to the science of physical therapy, of
Eleven of these studies were analytical. In 20 studies, the pathokinesiology? I will say yes but leave the degree of that
results of testing patient and healthy groups were compared. contribution to be assessed by others and time.

Volume 66 / Number 3, March 1986 383

Strengths and Weaknesses on knowledge gained by the basic science studies and encour-
age documentation of the effects of physical therapy by actual
Among our strengths must be counted the exposure, just measurements of changes in physiological functions and phys-
in the last four years, of more than 200 physical therapists to ical characteristics. This documentation will define better the
the research process. These experiences in designing and scientific basis of physical therapy and will help define the
conducting research in pathokinesiology should make them need for further studies. I believe that, despite research con-
more intelligent users of researchfindings,the only legitimate ducted in many places over the years, it is still true to say that
basis for decision making in clinical practice. They also should no physical therapy approach has been tested adequately.
be more appreciative of the limitations and variability of
researchfindings.I hope that some of the former students will
continue to participate in research, even if only at the single- Future Plans and Direction of Research
patient level. Most of the research tools used in our studies
are tools that also can be found in clinics and hospitals with We plan to expand the vitally necessary normative data
patient testing laboratories. As studies were designed to answer bases and patient data. We need to obtain data on the char-
clinical questions or to provide normative data against which acteristics and variability of patients with different disorders
to evaluate patient performance, the value of research to the and the degrees of those disorders. Do the gait characteristics
profession, in terms of improving patient care, should be of a patient group, for example, vary with severity of the
clear. Some unknowns have been identified, standards have disease? Can treatment also be assessed by monitoring im-
been formulated, and variability within healthy groups has provement in walking? I selected gait because most people
been established. walk in some manner, and tools such as the Rancho Gait
Results must be shared to ensure the growth of the body of Analyzer,2 developed for use in the clinic, make it possible
knowledge that will establish a recognizable science of path- for any therapist to quantify a patient's performance by the
okinesiology. We acknowledge that our publication efforts measurement of the gait characteristics. How do members of
a specific patient group differ from healthy subjects? How do
have lagged behind completion of research studies. When
they differ from other patient groups? Establishing these dif-
several students work on a clinical question over a period of ferences, if differences do exist, may contribute to the under-
two to five years, someone else must analyze thefinalsample standing of the disease process and the patient's rehabilitation.
and write the paper. An inadequate number of people have When such data become available, we plan to place greater
been available to do that, to write grants, to supervise ongoing emphasis, as conditions permit, on analytical studies to test
research, and to fulfill normal faculty responsibilities. These whether different treatments produce different effects, and if
are problems familiar to most physical therapists. Further- so, what those effects are. We intend to continue to identify
more, wefindthat students are keen to complete their research variables that may affect data. Does the distance over which
projects because completion terminates their formal studies gait data are collected, for example, influence those data?
and allows them to sit for the state board examination. In What distance is ideal for an indoor gait walkway? What is
theirfirstclinical appointment, however, conversion of their the influence of the time of day on data collection? Does it
accepted university paper to one suitable for submission for matter? Should patients with disorders such as rheumatoid
publication in a professional journal has low priority, despite arthritis only be tested after 10 AM? Is this hearsay or real?
prompting from faculty members. This problem decreases the What else is hearsay or real?
potential impact of the research conducted, but it has no easy We also will expand the methods of data analysis. We, for
solution. We have changed from the thesis format to a directed example, will make better use of multivariate and discrimi-
research format that permits the paper to be written in the nant analyses; identify major variables that influence perform-
style of the journal to which it may be submitted. The number ance to determine which data should be collected; and im-
of papers independently converted for publication and sub- prove the criteria for selection of candidates for specific
mitted by former students shows that this format change is therapeutic interventions, such as strengthening programs or
not enough. Where physical therapy faculty members are functional electrical stimulation. These plans include educat-
highly involved in the supervision of student research, their ing physical therapy students to have exposure to research, to
contribution to the science of pathokinesiology, and the over- gain a sound awareness of the importance of research to the
all development of the science of pathokinesiology, can be profession in providing the legitimate basis for clinical deci-
lessened by high involvement with students below the doctoral sion making, and to participate in some form of research in
level of study. If the body of knowledge is to be increased, the their clinical practice.
direction of those efforts of the still small number of ade-
quately qualified and trained faculty members needs to be We need to reevaluate the kinds and scope of research that
reconsidered. are requirements at the entry and advanced master's degree
levels. I believe that this component of our educational pro-
Other weaknesses in the research that may be identified but grams has the potential to affect significantly the development
not rectified easily are small sample sizes; subjects restricted of the science of pathokinesiology; to either increase or delay
in age, geographic origin, and social group; inadequate use of its development. We need to identify the approach that will
appropriate higher level statistical tests; a dearth of studies on be the most effective in achieving the goal of building a sound
homogeneous patient groups; and absence of analytical stud- knowledge base for the practice of physical therapy. Academic
ies investigating the effects of treatment regimens. These requirements for student research must be balanced by the
factors, not unique to our situation, impede the growth of the
necessity of allowing faculty members adequate time to per-
science of pathokinesiology.
form their own responsibilities. As the number of doctoral
We must discourage the tendency of the members of our programs increases, the need for additional faculty members
profession to speculate about the rationale for treatment based to provide adequate supervision and to serve as role models

384 Downloaded from http://ptjournal.apta.org/ by guest on April 14, 2012 PHYSICAL THERAPY

PATHOKINESIOLOGY

to their students also increases. In facilitating the acquisition the scientist, is obligated to delineate, without prejudice, what
of grant monies by faculty members and in providing sound is known, what is not known, and what probably is known
training to the future physical therapy research leaders, faculty using current methods.29 The advocate, the physical therapy
members will need to determine where their time would be clinician, advances or defends a particular approach through
spent most profitably—in giving research education to entry- selective presentation of information to support that ap-
level students or to more advanced students, such as those at proach. The physical therapy clinician and the lay person
the doctoral level. need to understand the uncertainty associated with scientific
A research laboratory, or laboratories, under the direction knowledge and to understand the concept of probability.
and control of the physical therapy education program is Without this understanding, it is difficult, if not impossible,
pivotal to the achievement of the objectives specified in a to use scientific knowledge as a basis for decision making. I
research plan. A gait laboratory is a vital component. Humans hope that the research efforts of USC-PT not only have
are bipedal and upright. Walking is a goal to be achieved by contributed to the body of knowledge of pathokinesiology but
most patients; thus, motor activity associated with gait is a also have prepared clinicians to understand, use, and partici-
common denominator of health, injury, and disease. Change pate in the research process.
in gait characteristics provides an index of motor ability and
independent function regardless of a patient's specific disease CONCLUSION
or diagnostic label.
A thought for the future, indeed now, is contract research, I end with a quote from Hislop's paper:
in which a research project will be conducted by faculty If you want a bee to make honey you do not issue directives
members for a clinical group or a manufacturer of physical and protocols on carbohydrate metabolism and solar naviga-
tion. You put him together with other bees. If the air is right,
therapy equipment, similar to the management of Depart- the science will come in its own season, like pure honey.1
ment of Defense contracts. This may maximize the clinician's
skills and the research expertise available in the university In this review of one facility's efforts toward the develop-
and in the clinical facilities. Such an arrangement should help ment of the science of pathokinesiology, I have described and
us obtain answers to the many questions posed by clinicians discussed the many facets of research at our facility. Research,
who lack the time or facilities to pursue them. scientific inquiry, is the sole means whereby the profession of
physical therapy stands to gain a sound scientific basis for its
practice. The growing body of knowledge of pathokinesiology
The Research Process and Roles is that basis.

To paraphrase a recent article on engineering by Harrison,29 REFERENCES
the research process consists of selecting a problem, the meth- 1. Hislop HJ: Tenth Mary McMillan lecture: The not-so-impossible dream.
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Volume 66 / Number 3, March 1986 385

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386 PHYSICAL THERAPY

Research in Pathokinesiology−−What, Why, and How
Joan M Walker
PHYS THER. 1986; 66:382-386.

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