J Manipulative Physiol Ther. 1996 Sep; 19(7): 441-5.

Predictors of side effects to spinal manipulative therapy.

Senstad O, Leboeuf-Yde C, Borchgrevink C.

Nordic Institute for Chiropractic and Clinical Biomechanics, Odense, Denmark.

OBJECTIVE: To study whether side effects of spinal manipulative therapy can be predicted and, if so, whether they are patient- or treatment-related. Also, to determine if there are different predictors for common reactions (i.e., local discomfort, headache, tiredness or radiating discomfort) and for uncommon reactions (i.e., dizziness, nausea, hot skin or "other" complaints). STUDY DESIGN: Data were collected in patient interviews using standard questionnaires in a prospective clinic-based survey. Several outcome variables (reactions during the course of treatment, reactions after each treatment, specific types of treatment reactions, severe or long-lasting reactions) were then cross-tabulated against sex, age, treatment session number, type of area treated, number of areas treated and type of treatment. SETTING: Chiropractic clinics in Norway. PARTICIPANTS: One hundred and two chiropractors (response rate: 70%) and 12 consecutive patients per chiropractor (resulting in 1058 chiropractic patients) attending for up to six treatments (totaling 4712 treatments). RESULTS: Some patient- and treatment-related predictors were identified. Women were more likely to report reactions to treatment than men. There were also differences between gender in the types of reactions reported. More reactions occurred during the first treatment sessions, when more than one spinal region was treated, or when the thoracic spine only was treated. However, there were no specific predictors for uncommon side effects. CONCLUSION: Some predictors to the side effects of spinal manipulative therapy were identified but more information is needed regarding their clinical significance.