Adverse events after cervical spinal manipulative therapy: consensus based classification and definitions

Cervical spinal manipulations (CSM) are frequently employed techniques to alleviate neck pain and headache. Minor and major complications following CSM have been described, though clear consensus on definition and the classification of the complications had not yet been achieved. As a result, incidence rates may be underestimated. The aim of this study was to develop a consensus-based classification of adverse events following cervical spinal manipulations which has good feasibility in clinical practice and research. Design: A three round Delphi-study. Medical specialists, manual therapists, and patients (n=30) participated in an online survey. In Round 1, participants were invited to select a classification system of adverse events. Potential complications were inventoried and detailed in accordance with the ICF and the ICD-10. In Round 2, panel members categorized the potential complications in their selected classification. During the third round, it was inquired of the participants whether they concurred with the answer of the majority of participants. Results: Thirty four complications were defined. Consensus was achieved for 29 complications for all durations [hours, days, weeks]. For the remaining five complications, consensus was reached for two of the three durations [hours, days, weeks]. Conclusions: A consensus-based classification system of adverse events after cervical spinal manipulation was developed which comprises patients’ and clinicians’ perspectives and has only a small number of categories. The classification system includes a precise description of potential adverse events and is based on international accepted classifications (ICD-10 and ICF). This classification system may be useful for utilization in both clinical practice and research.