To the Editor:

We write concerning the recently published article by Klougart  et al, (Klougart N; Leboeuf-Yde C, Rasmussen LR. Safety in chiropractic  practice. Part II: Treatment to the upper neck and the rate of  cerebrovascular incidents. J Manipulative Physiol Ther 1996; 19:563-9).  The authors should be commended for their exhaustive efforts in  evaluating the occurrence of cerebrovascular incidents in chiropractic  practice, a topic of great interest and importance to the profession (1,  2). Based on earlier conclusions by these authors (1); their  present study (2) and the findings of other authors (3-5), cervical  spine .rotational maneuvers have been found to be clearly more  associated with cerebrovascular accidents (CVAs) and cerebrovascular  incidents (CVIs), after spinal manipulation than other techniques.  Perhaps because of this fact, and the knowledge of the effects of  rotation upon vertebral artery blood flow (6), the authors attempted to  classify technique procedures as “rotation’. or “nonrotation” in their  retrospective analysis to estimate the occurrence of CVI s after  chiropractic treatment to the cervical spine.

Although the authors had good intentions in their survey to  attempt to identify what techniques might be associated with CVIs,  inherent problems exist in administering such a. survey to  chiropractors. The shortcomings may include (a) the failure to report  the use of several different techniques in a given treatment session (7,  8); (b) the reporting of a practitioner that they are using a  particular system (i.e., Gonstead), when in actuality they are not using  the appropriate protocols, screening procedures, case management,  set-ups, lines of drive, segmental contact points and vectors or  magnitude of force as taught and recommended by such a system and (c) a  wide variation of competency among practitioners (9). These issues  complicate the meaningfulness of any evaluation of a particular  chiropractic technique.

Although the authors acknowledged that “the unwanted side  effects” of the Gonstead technique may have been due to a modification  of the technique by the chiropractor, and that it may “include a  stronger element of rotation/extension than is generally thought,”  several questions still arise. Pertaining to the six cases reportedly  classified as “Gonstead,” were any of the treating practitioners trained  in the Gonstead technique, and how many hours of study were dedicated  to such training? Were any of the chiropractors certified in the  Gonstead technique? Did the practitioners use the protocols and  screening procedures suggested by the Gonstead system (10)? Did the  reported “Gonstead” practitioners use elements of rotation in the  set-up, or thrust procedure and to what degree (e.g.,-in case 10 it was  reported that no rotation was used, but in the other 5 cases it was not  mentioned whether rotation was used or not).

Moreover, assuming that “rotation” refers to rotation of the  cervical spine, or + or – 0 Y designation suggested by White and Panjabi  (11), for any valid conclusions to be made in a study of technique  comparison, differentiation must be made between techniques that provide  a thrust at the end range of the motion and those that only exhibit  limited + or – 0 Y rotation in the set-up and thrust. Classification of a  particular technique into one of three categories (rotational, low  rotational or nonrotational) instead of two (rotational or  nonrotational) would be more appropriate for significance. The authors  classified Gonstead as “mainly nonrotation,” yet elements of + or – 0 Y  are routinely included in both the set-up and thrust procedures for the  cervical spine in the Gonstead technique (10). Gonstead, therefore,  should have been classified under rotational or “low rotational,” which  would have significantly affected the extrapolated estimates for  rotation and nonrotation treatments regarding risk estimates for CVIs  among technique procedures.

To expound further, another case in question, specifically case  6, was considered a case of “definite nonrotation,” which involved a  patient who developed CVI-related symptoms after receiving “Traction”  and “Activator” combined in the treatment. The authors used this data to  formulate their conclusion, “although there seems to be a link between  upper cervical rotation manipulative techniques and cerebrovascular  incidents, treatment to the lower neck and the use of other techniques  are implicated. as well.”

Because both traction and Activator were used in the treatment  of the patient in case 6, and the methodology of neither treatment was  neither explained nor discussed, it is impossible to draw a conclusion  specific to the use of Activator or a “nonrotation” technique in this  case, which deserves mention. The authors failed to provide discussion  of this issue, as they did pertaining to “Gonstead technique” in the  preceding paragraph regarding the modification of the technique by the  individual chiropractor. We want to make it clear that practitioners  trained in use of the Activator Adjusting Instrument (AAI) and Activator  Methods Chiropractic Technique (AMCT) are not taught to incorporate  traction into treatment regimens and, furthermore, that cervical spinal  adjustments/manipulations are performed in the prone neutral position  (12-14). Because there are several types of traction in use in  chiropractic practice, some of which contain postures away from neutral  including flexion and extension (15), the authors understandably  referenced how the vertebral artery can be affected through traction  (16). They further noted that “toggle” and “Activator” techniques seem  not to be under suspicion in CVIs after spinal manipulation.


J Manipulative Physiol Ther. 1997 Oct;20(8):567-8. [PMID:9345689]

Author information: Colloca CJ, Fuhr AW. Activator Methods International Ltd., Phoenix, AZ.

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