High velocity, low amplitude (HVLA) adjustments are a common form of chiropractic manipulation. Although chiropractic adjustments are usually carried out by hand, instrument adjusting has become an increasingly popular method of manipulation in chiropractic treatment. In fact, instrument adjusting is now the most commonly used chiropractic technique after manual spinal manipulation. A wide variety of professional adjustment instruments are available on the market, ranging from mechanical spring-loaded models to high-tech, electrically powered brands. These are held by hand to administer force to the precise area of treatment.
Chiropractic adjustment instruments are designed to provide fast and targeted adjustments to a patient at around 100 times the speed of a manual adjustment. Whereas manual adjustment will vary depending on the precise force of the practitioner, adjustment instruments can be set to deliver the same impact on each adjustment. Further, the small tip of adjustment instruments can be targeted much more precisely than human hands. In addition to these advantages, adjustment instruments do not cause the popping and cracking sounds that typically accompany manual manipulation, which makes them particularly useful when treating nervous patients such as children and seniors.
Being treated with an adjustment instrument has been described as feeling like a light tapping on the treated area. The treatment is usually painless, and patients often report reduced pain and greater mobility following adjustment. There is also evidence to suggest that instrument adjusting may lead to fewer painful side-effects than manual manipulation. The precision of adjustment instruments can be used to move spinal vertebrae without disturbing adjacent muscles, which results in less pain for the patient. In addition to being better for patients, using adjuster instruments reduces the physical impact of practice on chiropractors who can—ironically—suffer from carpal tunnel and postural problems brought about from frequent daily applications of manual treatment to patients.
Although the research on the use of adjustment instruments is still in its infancy, several studies have demonstrated the effectiveness of this form of treatment for a wide range of musculoskeletal problems. The fact that it has found widespread acceptance in modern chiropractic therapy suggests that many chiropractors themselves have become convinced of the practical use of mechanical adjustment, and that it is likely to remain a core part of chiropractic treatment for the foreseeable future.