Practitioner Experience Best Indicator of Success in Cervical Spine Manipulation Cavitation
Cervical spine studies have historically indicated that manipulation (and the generation of cavitation) by a qualified practitioner is the most effective means of treatment for neck pain, far exceeding placebos or exercise. Though there are various definitions and modalities of cervical manipulation, in general, treatment involves the use of applied force in a single direction perpendicular to the affected cervical joint surface. The widely-accepted indicator of the success of any manipulation is an audible “pop” or other sound produced by the joint’s cavitation, regardless of which technique is applied in the manipulation.
A recent study 1 compared the results of four practitioners’ spine manipulation therapies on the relative range of motion (ROM) in four control groups. The subjects of the study—students with no history of neck pain—were analyzed for relative ROM prior to, and after manipulation therapy. Practitioners involved in the study represented a range of experience (1,20, and 20 years) in cervical spine manipulative therapy. They employed “classic” HVLA technique (in which the patient is in an upright, seated position, with shoulders relaxed) on their subjects, who were fitted with spine motion analyzers attached to an adjustable helmet and harness prior to their manipulations. The volunteers—9 women and one man whose average age was 25 years—were manipulated one-to-four times by each of the four practitioners, who were instructed to discontinue the manipulations after achieving cavitation or after four attempts. An independent observer collected kinematics data during the experiment. This data was later analyzed to determine the rate of cavitation occurrence during each practitioner’s C3 and C5 thrust manipulations. The procedures used in the study employed a low magnitude of axial rotation to reduce the risk of potential cervical artery dissection.
The study concluded that there was little relevance in the direction of applied forces in the vertebral manipulation. Rather, the number of years a practitioner had been in practice was a more reliable indicator of kinematic impact on the subjects in the study. The most experienced practitioners most consistently achieved acceleration magnitude and produced cavitation. Their therapies consistently improved neck mobility and relative ROM in their subjects, suggesting that certain kinematics parameters are most likely linked with the occurrence of cavitation for thoracic manipulation.
- Assessment of in vivo 3D kinematics of cervical spine manipulation: Influence of practitioner experience and occurrence of cavitation noise ↩