The Activator Method is part of the tradition of instrument adjusting in chiropractic dating to the first decade of the profession, and even farther back into antiquity. Credit for the origin of the Activator adjusting instrument rests with two rural Minnesota practitioners (Arlan W. Fuhr and Warren C. Lee). Activator Method assessment procedures have multiple conceptual roots, all of which are anchored in various subluxation theories. The growth of the Activator Method has been based primarily on patient and clinician satisfaction, but Activator Methods International, Ltd. has sought to hold its methods up to the critical scrutiny of scientific inquiry. Bioengineering research has suggested a number of mechanical improvements in the Activator adjusting instrument over the years, and this work continues. A clinical outcomes evidence base combined with clinician observation has prompted generally favorable reviews of the Activator Method. This form of instrument adjusting has become usual and customary within the profession and is widely taught in chiropractic colleges and in postgraduate re-licensing seminars.
2. Principles & Theories:
The leg measuring practice of the Activator Method is the only chiropractic method of analysis with solid research supporting its reliability and reproducibility. In contrast, most chiropractic techniques provide treatment based on static, weight-bearing films combined with range of motion testing and static palpation all of which have poor interexaminer reliability. The Activator Method utilizes a prone leg check of each patient to evaluate individualized need for treatment as well as a feedback mechanism that the treatment was successful. Prone leg-length analysis as applied in the Activator Method has good to very good reliability in a body of referenced literature.
The patient is initially placed prone on a table and the Activator doctor evaluates to see if one leg is shorter than the other one. This initial analysis is a sign of lumbopelvic, insufficient stability which involves pelvic rotation and visualization of a “short leg”. A minority of the population has a true “anatomical” short leg which is taken into consideration with the leg measurement. The commonly observed short leg is a “functional” short leg – a sign of a neurological and/or biomechanical involvement that causes imbalance in the body. There are multiple steps of analysis involved. The functional short leg is compared from a passive prone position to a 90-degree flexed position. This allows the Activator doctor to determine where to specifically adjust the patient with the Activator instrument. Balancing of the leg lengths occur after the adjustment; giving feedback to the doctor that a correction was made to a neuroarticular dysfunction (a subluxation complex in chiropractic language). After the initial balancing occurs and lumbopelvic stabilization is achieved biomechanically and neurologically, the Activator doctor then can utilize an isolation test. An isolation test involves the patient performing a passive movement while lying on the examination table. Following this movement the leg lengths are then viewed in the prone position followed by the flexed position to determine if treatment is needed for the joint that was known to be neurologically assessed. Changes in the leg length between these two positions determine the exact placement of the instrument on the spine or extremities for treatment. For example, the isolation test may indicate treatment on the right transverse process of the sixth thoracic vertebra. This series of analysis begins with the low back and progresses toward the head with tests for each vertebral segment available. Isolation tests are also utilized for the extremities as well. Isolation tests have also been documented in the research for its relationship, reliability, and validity to the patient’s individual symptoms.
References follow from pages 134-136 in The Activator Method Second Edition. Also please see pages 132 and 133 along with Chapter 5, Leg Length Reactivity.
The Activator Method is a low-force technique. There are three different instruments at the present time. The Activator I is an inexpensive instrument for the beginner. The Activator II is a more well-researched instrument for causing the co-activation of mechanoreceptors. The most sophisticated and researched instrument is Activator IV that contains a pre-load feature that ensures the coactivation of a greater quantity of mechanoreceptors with each thrust. The preload feature assures reproducibility of force even for the beginning practitioner. The Activator instrument is used from pediatrics to geriatrics.
There are two levels of training certification: (1) Proficiency: Requires successful completion of a written and practical exam at the college level or 12 hours of post-graduate training followed by successful completion of a written and practical exam; (2) Advanced Proficiency: Requires successful completion of a written and practical exam at the college level or 24 hours of post-graduate training followed by successful completion of a written and practical exam.
The Activator Method has been committed to research for greater than 20 years. There are 25 peer-reviewed research papers pertaining to the effectiveness of the Activator instrument. There are currently 15 papers pertaining to the reliability and reproducibility of the leg-length analysis.
The Activator Method is currently being researched with funds from two NIH grants. One is a study of the TMJ being conducted at Palmer College in collaboration with the University of Iowa Dental School. The other is being conducted at Parker College studying the reduction of inflammation using the Activator on laboratory animals.
Our commitment remains focused on continued research that centers on major clinical trials.
The Activator Method has greater than 100 published research papers. These may be accessed via www.activator.com under the “Research” tab.
6. Picture or Graphics:
7. Standard Journal Article
Fuhr AW, Menke JM. Status of Activator Methods Chiropractic
Technique, Theory, and Practice. J Manipulative Physiol Ther 2005; 135.e1-135.e20.
8. Standard Journal Article on the Internet
Roy RA, Boucher JP, Comtois AS. Effects of a Manually Assisted Mechanical Force on Cutaneous Temperature. J Manipulative Physiol Ther 2008;3/4:230-6.
9. Standard Book
Fuhr AW, The Activator Method, 2nd ed., St. Louis: Mosby, 2009.
10. Standard citation to a home page
11. Newspaper or Magazine Article
Chiropractic research center opens in Phoenix. The Business Journal (Phoenix).
2005 Jan 21;15.
Arlan W. Fuhr: The Art of Healing. The Business Journal (Phoenix). 2005 Nov 18; 29.