Wilhelmine Wright and Robert W. Lovett, MD,
Professor of Orthopedic Surgery at Harvard University
Medical School, were the originators of the muscle
testing system that incorporated the effect of gravity.1 , 2
Janet Merrill, PT, Director of Physical Therapeutics at
Children's Hospital and the Harvard Infantile Paralysis
Commission in Boston, an early colleague of Dr.
Lovett, stated that the tests were used first by Wright
in Lovett's office gymnasium in 1 9 1 2 . 3 The seminal
description of the tests used today was written by Wright
and published in 19121 ; this was followed by an article
by Lovett and Martin in 1 9 1 6 4 and by Wright's book
in 1 9 2 8 . 5 Miss Wright was a precursor of the physical
therapist of today, there being no educational programs
in physical therapy in her time, but she headed Lovett's
physical therapeutic clinic. Lovett credits Wright fully
in his 1917 book, Treatment of Infantile Paralysis,6 with
developing the testing for polio (see Sidebar). In
Lovett's 1917 book, muscles were tested using a
resistance-gravity system and graded on a scale of 0 to
6. Another early numerical scale in muscle testing was
described by Charles L. Lowman, M.D., founder and
medical director of Orthopedic Hospital, Los Angeles.7
Lowman's system ( 1 9 2 7 ) covered the effects of gravity
and the full range of movement on all joints and was
particularly helpful for assessing extreme weakness.
Lowman further described muscle testing procedures in
the Physiotherapy Review in 1940.8
H.S. Stewart, a physician, published a description
of muscle testing in 1925 that was very brief and was
not anatomically or procedurally consistent with what
is done today.9 His descriptions included a resistance based
grading system not substantially different from
that in use today: maximal resistance for a normal
muscle, completion of the motion against gravity
with no other resistance for a grade of Fair, and so
forth. At about the time of Lowman's book, Arthur
Legg, MD, and Janet Merrill, P.T., wrote a valuable small book on poliomyelitis in 1932. This book,
which offered a comprehensive system of muscle testing,
was used extensively in physical therapy educational
programs during the early 1940s; muscles were
graded on a scale of 0 to 5, and a plus or minus designation
was added to all grades except 1 and 0 . 1 0
Henry and Florence Kendall were among the earliest
clinicians to organize muscle testing and support such
testing with sound and documented kinesiologic
procedures in the way they are used today. Their earliest
published documents on comprehensive manual
muscle testing became available in 1936 and
1 9 3 8 . 1 1 , 1 2 The 1938 monograph on muscle testing
was published and distributed to all Army hospitals
in the United States by the U.S. Public Health
Service. Another early contribution came from Signe
Brunnstrom and Marjorie Dennen in 1931; their syllabus
described a system of grading movement rather than individual muscles, as a modification of Lovett's
work with gravity and resistance.1 3
In this same time period, Elizabeth Kenny came
to the United States from Australia, where she had
unique experiences treating polio victims in the
Australian back country. Kenny made no contributions
to muscle testing, and in her own book and
speeches she was clearly against such an evaluative
procedure, which she deemed to be harmful.1 4 Her
one contribution was to heighten the awareness of
organized medicine to the dangers of prolonged and
injudicious immobilization of the polio patient,
something that physical therapists in this country had
been saying for some time but were not widely
heeded at the time.1 2 , 1 3 , 1 5 , 1 6 Kenny also advocated the
early use of "hot fomentations" (hot packs) in the
acute phase of the disease.1 4 In fact, Kenny vociferously
maintained that poliomyelitis was not a central
nervous system disease resulting in flaccid paresis or
paralysis, but rather "mental alienation" of muscles
from the brain.1 5 , 1 6 In her system "deformities never
occurred,"1 4 but neither did she ever present data on
muscular strength or imbalance in her patients at any
point in the course of their disease.1 5 , 1 6
The first comprehensive text on muscle testing still
in print (which went through five editions) was written
by Lucille Daniels, PT, MA, Marian Williams, PT, PhD,
and Catherine Worthingham, PT, PhD, and was
published in 1 9 4 6 . 1 7 These three authors prepared a
comprehensive handbook on the subject of manual testing procedures that was concise and easy to use.
It remains one of the most used texts the world over
and is the predecessor of the sixth, seventh, and this
eighth edition of Daniels and Worthingham's Muscle
Testing.
The Kendalls (together and then Florence alone
after Henry's death in 1979) developed and published
work on muscle testing and related subjects
for more than six decades, certainly one of the more
remarkable sagas in physical therapy or even medical
history.1 8 - 2 0 Their first edition of Muscles: Testing
and Function appeared in 1949.1 8 Earlier, the
Kendalls had developed a percentage system ranging
from 0 to 100 to express muscle grades as a reflection
of normal; they then reduced the emphasis on
this scale, only to return to it in the latest edition
( 1 9 9 3 ) , in which Florence again advocated the 0 to
10 scale.2 0 The contributions of the Kendalls, however,
should not be considered as limited to grading
scales. Their integration of muscle function with posture
and pain in two separate b o o k s 1 8 , 1 9 and then in one
book2 0 is a unique and extremely valuable contribution
to the clinical science of physical therapy.
Muscle testing procedures used in national field
trials that examined the use of gamma globulin in the
prevention of paralytic poliomyelitis were described by
Carmella Gonnella, Georgianna Harmon, and Miriam
Jacobs, all physical therapists.2 1 The later field trials
for the Salk vaccine also used muscle testing procedures.
2 2 The epidemiology teams at the Centers for
Disease Control were charged with assessing the validity
and reliability of the vaccine. Because there was
no other method of accurately measuring the presence
or absence of muscular weakness, manual muscle testing
techniques were used.
A group from the D.T Watson School of
Physiatrics near Pittsburgh, which included Jesse
Wright, MD, Mary Elizabeth Kolb, PT, and Miriam
Jacobs, PT, PhD, devised a test procedure that
eventually was used in the field trials. The test was
an abridged version of the complete test procedure, but
it did test key muscles in each functional group
and body part. The test used numerical values that were
assigned grades, and each muscle or muscle group also
had an arbitrary assigned factor that corresponded (as
closely as possible) to the bulk of the tissue. The
bulk factor multiplied by the test grade resulted in an
"index of involvement" expressed as a ratio.
Before the trials, Kolb and Jacobs were sent
to Atlanta to train physicians to conduct the
muscle tests, but it was decided that experienced
physical therapists would be preferable to maintain
the reliability of the test scores.2 3 Lucy Blair,
then the Poliomyelitis Consultant in the American
Physical Therapy Association, was asked by Catherine
Worthingham of the National Foundation for
Infantile Paralysis to assemble a team of experienced
physical therapists to conduct the muscle tests for the
field trials. Kolb and Jacobs trained a group of 67 therapists in the use of the abridged muscle test.2 3 A
partial list of participants was appended to the
Lilienfeld paper in the Physical Therapy Review in
1 9 5 4 . 2 2 This approach and the evaluations by the
physical therapists of the presence or absence of
weakness and paralysis in the field trial samples eventually
resulted in resounding approval of the Salk
vaccine.
Since the polio vaccine field trials, sporadic research
in manual muscle testing has occurred as well
as continued challenges of its worth as a valid clinical
assessment tool. Iddings and colleagues noted that
intertester reliability among practitioners varied by
about 4 percent, which compares favorably with the
3 percent variation among the carefully trained therapists
who participated in the vaccine field trials.2 4
There is growing interest in establishing norms of
muscular strength and function. Early efforts in this
direction were begun by Willis Beasley2 5 (although
his earliest work was presented only at scientific
meetings) and continued by Marian Williams2 6 and
Helen J. Hislop,2 7 , 2 8 which set the stage for objective
measures by Bohannon2 9 and others. The literature
on objective measurement increases yearly—an effort
that is long overdue. The data from these studies
must be applied to manual testing so that correlations
between instrumented muscle assessment and
manual assessment can ensue.
In the meantime, until instrumented methods
become affordable for every clinic, manual techniques
of muscle testing will remain in use. The skill
of manual muscle testing is a critical clinical tool that
every physical therapist must not only learn but also
master. A physical therapist who aspires to recognition
as a master clinician will not achieve that
status without acquiring exquisite skills in manual
muscle testing and precise assessment of muscle
performance.
In the spring of 1 9 0 7 Dr. Robert W. Lovett
placed me in charge of the gymnasium which he
and Dr. James S. Stone maintained for the use
of their orthopedic patients. A fairly large percentage of
these patients had muscles weakened by infantile paralysis,
and it was my task to exercise these weakened muscles. In
order to do that I necessarily had to know, in the case of
each muscle, what movements would bring about contraction;
but who could tell me that? Gray ("Anatomy")
gave outward rotation of the thigh as an action of the adductor
group; but when I asked a patient lying on his
back to rotate his thighs inward, the adductors contracted
strongly. Which was right? Nature or Gray? Could it be
possible both were right?
Again, all anatomists since Duchenne were agreed that
the lumbricales flexed the proximal joints of the fingers
and extended the other two. This being the case, was it
to be assumed that the lumbricales worked when all three
joints of the fingers were flexed and likewise when all
three joints were extended? How could one test the
strength of the lumbricales, and how could one best exercise
them when weak? It was this sort of question to
which I found no immediate answer. . . .
The large numbers of paralyzed patients examined in
the clinics gave me the opportunity to observe endless
combinations of paralyzed and normal muscles—one
muscle left normal when all others of its group were
gone, or one muscle of a group paralyzed when all others
retained normal power, etc. I watched with the patience
of a cat before a mouse-hole; and now and then, perhaps
once in a year or once in two years, an explanation of
one of my puzzles would show its head cautiously and I
would pounce upon it in joyous excitement. . . .
I happened upon a small book . . . by Beevor
("Croonian Lectures on Muscular Movements") . . .
and I tried to do for the lower extremity what Beevor
had so ably done for the upper. Later I decided to complete
my work by testing the movements of the upper extremity
also in the hope that I might throw a little more
light on some problems that Beevor had not satisfactorily
solved.
Beevor's method of investigation, which he called
"physiological or natural method," was that in which "a
living person is told to perform a definite movement, and
it is then observed which muscles take part in this movement."
The advantages of this method over the anatomical
one of pulling muscles in a dead body or strings attached
on a skeleton and observing the resulting movement, and
over the electrical one of faradizing the muscle under examination,
are that it tells us, not "what a muscle may
do," but "what a muscle does do." . . .
My thanks are due to Dr. Lovett who had the generosity
of mind to encourage original thinking by his subordinates.
. . .
WILHELMINE WRIGHT
PREFACE ( 1 9 2 7 ) TO MUSCLE FUNCTION. NEW YORK: PAUL
HOEBER, 1 9 2 8
The material . . . for this subject has been furnished
by my senior assistant in private practice,
Miss Wilhelmine G. Wright, who has for some
years devoted practically her whole time to this department
of physical therapeutics and who has already published
an article on the subject. I am greatly indebted to
her for formulating for me the exercises and tests. . . .
ROBERT W. LOVETT, MD
PREFACE TO TREATMENT OF INFANTILE PARALYSIS.
PHILADELPHIA: BLAKISTON'S, 1 9 1 7
(thanks to Daniels and Worthingham's
MUSCLE
TESTING
Techniques of Manual Examination)
