Duarte Felipe Coutinho Kullmann, Kolberg Carolina, Barros Rodrigo R, Silva Vivian G A, Gehlen Günter, Vassoler Jakson M, Partata Wania A
Academic Researcher, Department of Physiology, Institute of Basic Health Science, Federal University of Rio Grande do Sul/UFRGS, Porto Alegre, Brazil.
Academic Researcher, Department of Physiology, Institute of Basic Health Science, Federal University of Rio Grande do Sul/UFRGS, Porto Alegre, Brazil.
J Manipulative Physiol Ther. 2014 May;37(4):236-41. doi: 10.1016/j.jmpt.2014.02.004. Epub 2014 May 2.
This study was designed to assess the peak force of a manually operated chiropractic adjusting instrument, the Activator Adjusting Instrument 4 (AAI 4), with an adapter for use in animals, which has a 3- to 4-fold smaller contact surface area than the original rubber tip.
Peak force was determined by thrusting the AAI 4 with the adapter or the original rubber tip onto a load cell. First, the AAI 4 was applied perpendicularly by a doctor of chiropractic onto the load cell. Then, the AAI 4 was fixed in a rigid framework and applied to the load cell. This procedure was done to prevent any load on the load cell before the thrust impulse. In 2 situations, trials were performed with the AAI 4 at all force settings (settings I, II, III, and IV, minimum to maximum, respectively). A total of 50000 samples per second over a period of 3 seconds were collected.
In 2 experimental protocols, the use of the adapter in the AAI 4 increased the peak force only with setting I. The new value was around 80% of the maximum value found for the AAI 4. Nevertheless, the peak force values of the AAI 4 with the adapter and with the original rubber tip in setting IV were similar.
The adapter effectively determines the maximum peak force value at force setting I of AAI 4.
