Influence of Verbal Suggestion on the Therapeutic Effect of the Joint Manipulation

Participant lies in the supine position, a physiotherapist faces the participant's side that will be manipulated. The participant interlocks their fingers behind their neck. Then the physiotherapist turns the participant on their side and performs a short thrust across the participant's pelvis in a posterior and inferior direction. The manipulation will be carried out on the symptomatic side, based on the participant's indication of the painful side. If the participant is unable to indicate the more symptomatic side, the physiotherapist performing the procedure will select the side. If no audible cavitation occurs during the manipulation, the physiotherapist will attempt to manipulate the opposite side. A maximum of 2 attempts per side will be allowed.

"Participants from Group A who will undergo the joint manipulation of the lumbar spine region and receive the following information: Joint manipulation is a very effective method of treating spinal disorders, which will significantly reduce the low back pain you are experiencing (positive communication - placebo)."

"Participants form Group B who will undergo the joint manipulation of the lumbar spine region and receive the following information: Joint manipulation is not an effective method of treating spinal disorders, thus it may temporarily increase the low back pain you are experiencing (negative communication - nocebo)."

"Participants from Group C who will undergo the joint manipulation of the lumbar spine region and receive the following information: Joint manipulation has not been verified for its effectiveness in affecting your level of low back pain (neutral communication)."