spring balance tests and also included resistance tests with good and normal
gradings.
Modifications of the initial scoring system by Dr. Charles Lowman (developed
in 1922) resulted in a numerical scoring system to be used with gravity
tests through ranges of active joint motion. Lowman developed a chart for grading
muscles that was published in his textbook on underwater gymnastics (1937)
and other works (1927, 1940). Legg and Memll, associates of Lovett, developed
variations of test positions and muscle groups.including the concepts of "poor"
and "fair" as applied to testing muscles (Legg & Memll, 1932).
Kendall and Kendall (1939) developed a percentage grading system from
100% to 0%, basing the range on the effects of gravity and resistance. Suhsequently,
Brunnstrom (1941) recognized subjectivity problems with the scoring
system and recommended changes that led to a more standardized testing protocol
similar to the scale used today.
In the early 1940s, a system for recording muscle function in poliomyelitis
was used to analyze muscle function and strength. In the early 1950s, Dr. Jesse
Wright built upon Lovett's earlier work concerning gravity and grading and
developed a scale from 0 = normal to 5 = paralyzed. Wright also developed an
index of involvement by multiplying the muscle grade with the bulk of the
muscle.
Despite continued attempts to improve the scoring system and clinicians'
increased experience in using manual muscle testing, several decades have passed
without resolution of the problem of excessive variability and subjectivity among