By Dr. Vic Weatherall
Unfortunately, there is often great confusion in terminology and understanding within the various health care professions. This is likely due to the fact that different professions look at the same action from different perspectives and educational experiences. However, the goal in manual therapy remains the same: the use of a therapist's hands to relax and stretch joints and muscles to provide pain relief and restore proper joint operation at the joint itself and throughout the body.
Joint "mobilization" is a subtype of joint manipulative therapy in which the therapist moves the joints in specific directions and depths with, or without, the patient's assistance, to stretch the joint and its surrounding tissues.
Mobilization is different from the high-velocity, low amplitude (HVLA) thrust joint manipulation employed by chiropractors and other manual therapists. Chiropractors refer to HVLA thrust manipulation as a chiropractic "adjustment," spinal manipulative therapy (SMT), or simply "manipulation."
Thrust manipulation involves rapidly moving the joint beyond its physiologic or normal operating range of motion and below its anatomical or maximum limit of motion. This rapid distraction or gapping of the facet joint surfaces is often accompanied by an audible "crack" or "pop" caused by the formation of tiny gas bubbles (this is called cavitation) in the joint fluid. This sound and the gas bubbles have no therapeutic properties but may indicate a clean separation of the joint surfaces.1
Like other forms of manipulation, thrust manipulation provides pain relief and helps restore normal joint function. It does this by
The major difference in the action of mobilization and thrust manipulation is that during mobilization, reflex muscle relaxation—a key component in pain relief—does not occur.2 Also, thrust manipulation has been shown to provide much more rapid pain relief.3
The difference in the effectiveness between thrust manipulation and non-thrust manipulation is, obviously, of great interest to chiropractors and other manual therapists. Unfortunately, most trials of manipulative therapy compared to conventional medical and physical therapies do not include both thrust and non-thrust manipulation and if they do, they do not separate the different forms within the study. A neck pain study in the Annals of Internal Medicine4 is a good example. In fact, the specific form of "mobilization" is not identified at all—the key point was superiority of manual therapy versus the other therapies.
All chiropractors are trained in the use of thrust and non-thrust joint manipulative techniques: chiropractic is not only thrust manipulation. This is a notion sometimes promoted by its competitors or detractors. However, the primary focus of the manipulative therapy training of chiropractors, and hence the most common form of chiropractic treatment, is thrust manipulation. This form of manual therapy is by far the most difficult to learn and perform skillfully. Other techniques also require great skill, but are essentially variations on the theme of stretching the joint.
Chiropractors employ a variety of different forms of manipulation from a basic holding stretch (also known as myofascial release) to thrust manipulation. All are effective in the appropriate application and the choice of which form of manipulation to use depends on the patient’s informed consent and several factors.
These include, but are not limited to