Validation of a novel sham cervical manipulation procedure

Abstract

Background Context No clinical trial of spinal manipulation for chronic neck pain, either for single or multiple intervention session(s), has employed an effective sham-manipulation control group. Purpose Validate a practical sham cervical high velocity, low amplitude (HVLA) spinal manipulation. Study design/Setting Randomized, experimental validation study in an institutional clinical research laboratory Patient Sample Eligible subjects were males and females, 18–60 years of age with mechanical neck pain (as defined by the International Association for the Study of Pain Classification) of at least 3 months duration. Subjects with arm pain, any pathologic cause of neck pain or any contra-indication to spinal manipulation were excluded. Outcome Measures The primary outcome was the patient’s self-report or “registration” of group allocation following treatment. Secondary outcomes were NRS-101 for neck pain, range of motion (by goniometer), tenderness (by pressure algometry). Methods Eligible subjects were randomly allocated to one of two groups: “real” or sham cervical manipulation (RM or SM). All subjects were given two procedures in sequence, either RM+SM or SM+SM. Immediately following the two procedures, subjects were asked to register any pain experienced during the procedures and to identify their treatment group allocation. Force-time profiles were recorded during all procedures. Secondary clinical outcome measures were obtained at baseline, 5 and 15 minutes after the intervention including range of motion, self-report of pain and local spinous process tenderness. Data for each variable were summarized and tested for normality in distribution. Summary statistics were obtained for each variable and statistically tested. Funding for this study was obtained from the National Institutes of Health (NCCAM: R21 AT004396-01A1) and the Canadian Institutes of Health Research (BMT91926). No conflicts of interest exist in this study. Results Sixty-seven subjects were randomized. Data from 64 subjects (32 per group) were available for analysis. There were no significant differences between the groups at baseline. One adverse event occurred in the “real” group which was a mild post- treatment pain reaction lasting < 24 hours. In the RM group, 50% of subjects incorrectly registered their treatment allocation; in the sham group, 53% did so. For the SM group, none of the procedures resulted in cavitation while in the RM group, 87% of procedures resulted in cavitation. There were no significant changes between groups on pain, tenderness or ROM. Force-time profiles of the RM and SM procedures demonstrated fidelity with significant differences between components as intended. Conclusions The novel sham procedure has been shown to be effective in masking subjects to group allocation and to be clinically inert with respect to common outcomes in the immediate post-treatment stage. Further research on serial applications and for multiple operators is warranted.

Influence of the cervical spine manipulation in the neck disability index in patients with chronic neck pain: A preliminary study

“…A systematic review showed that sham-controlled trials of CSM are feasible; also, they demonstrate that CSM is associated with a sizeable placebo effect, which arguably creates the necessity to test CSM with sham-controlled clinical trials, particularly if the research question is aimed at identifying specific therapeutic effects. (6) When Vernon et al (21) validated SMPCS, they analyzed that more patients reported improvement in pain following the real manipulation than the sham manipulation (38% vs 28% in the sham group) with the same sham procedure used in this study, but with no statistically significant intergroup differences in pain, pain threshold or range of motion.…”

“…To our knowledge, this study was the first to compare the treatment outcomes among that type of CSM (19,20) and a validated cervical manipulative sham procedure (14,21) using the NDI to evaluate patients with chronic neck pain. A systematic review showed that sham-controlled trials of CSM are feasible; also, they demonstrate that CSM is associated with a sizeable placebo effect, which arguably creates the necessity to test CSM with sham-controlled clinical trials, particularly if the research question is aimed at identifying specific therapeutic effects.…”

“…(4,5,14,21,22,27) In addition, in a systematic review of Vernon et al (27) they affirmed that in 8 of 21 trials that evaluated CSM and some type of sham-controlled manipulation the control procedure resulted in a mean change that wasn't clinically important and bellow the minimal clinically important threshold. Moreover the SMPCS used in a single treatment application suggested that it is a clinically inert treatment due to the lack of change in measures of pressure pain threshold, spontaneous pain and range of motion.…”

“…For the SG, it was used a validated SMPCS simulating the sensory experience of a high-velocity, low-amplitude manipulation procedure with the 4 components of the procedure: touch the region with dysfunction, head positioning, movement and sound with the help of the headpiece table-drop (see Figure 2), (14,21) that is a tool for improve the speed in some types of manipulations. This procedure proved to be valid immediately after and until 48 hours after the intervention to blind the SG and should be applied in experimental studies to determine whether the treatment results are attributed to the intervention or to a non-specific placebo effect.…”

“…(6) It is notable that manipulation can lead to an improvement on the course of neck pain and disability with better patient satisfaction. (7,9,10,18) Therefore, the main objective of this study was to evaluate the CSM (19,20) in comparison with a Sham Manipulative Procedure for the Cervical Spine (SMPCS) (14,21,22) on the course of the neck pain and disability.…”