Assessment of vertebrobasilar artery insufficiency: a clinical audit and literature review.

Abstract

As cerebrovascular accidents are now increasingly documented in the literature and represent perhaps the most serious side effect of chiropractic upper cervical manipulation, this study was designed to audit the risk assessment process in patients prior to manipulation in a group chiropractic practice. A questionnaire was devised to evaluate the performance of provocational tests and the recording of risk factors. It also examined the procedures carried out in the small numbers of patients who tested positive to vertebrobasilar insufficiency provocation. The audit was carried out in two cycles three months apart. Weaknesses in clinical procedure were identified following the first round audit, and assessment procedures modified in line with recommendations from reviewing the available literature. Improvements were generally evident in the performance of provocation tests, but practitioner recording of historical risk factors at initial consulation, although improved, remained poor. The study is accompanied by a literature review designed to establish the evidence underlying the use of provocational tests, and to consider whether these tests should become mandatory in any forthcoming guidelines for chiropractic practice in this country. After reviewing the evidence available in the biomedical literature, it was apparent that there maybe alterations in blood flow at the upper cervical segment during rotation and extension, but that the vertebral artery is not completely occluded and that the test is therefore not conclusive in identifying patients at risk. The astute practitioner can strengthen their position in this respect by careful assessment of risk factors in the case history, avoiding extremes of rotation and extension and by refraining from repeated rotary manipulations in patients who have experienced post-manipulation dizziness. However, it appears that cerebrovascular accidents can occur even where all these precautions have been taken, that provocation tests are an unreliable indicator and should be omitted from the pre-manipulative recommendations of any future guidelines.