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