Serious adverse events associated with conservative physical procedures directed towards the cervical spine: A systematic review

Background: Previous reviews on serious adverse events (SAEs) following physical interventions involving the neck have focused on vascular SAEs or those related to cervical manipulation.

Objective: To review the evidence for all serious adverse events associated with any physical cervical procedures and describe SAE characteristics.

Methods: Searches were conducted in PubMed, EMBASE, CINAHL, Scopus, Cochrane, Web of Science and Index to Chiropractic Literature from inception to May 2023 for studies reporting characteristics of SAE following any neck intervention and patient demographics.

Results: Two hundred and thirty-three studies describing 334 SAE cases were identified. Forty-one were reported in the last 5 years. The results confirmed findings of past reviews with most events being vascular (58%) and mainly arterial dissection or vertebral artery related and the majority involving manipulation (75%). However lesser-known SAES ie neurological (25%), combined vascular/neurological (12%) and others (5%) which included cases such as cerebrospinal fluid leaks, phrenic nerve palsies and retinal detachments were identified. Further, some followed procedures such as vestibular testing, gentle mobilization, exercises, acupuncture or even massage. Initial symptoms included sharp increases in headache/neck pain, nausea, vomiting, dizziness and altered sensation, during treatment or within 48 h, often preceding neurological signs. Most recovered favourably (62%), 16% with disability, 6% died, the rest were unspecified.

Conclusion: Most SAEs were vascular and associated with manipulation but awareness of potential neurological and orthopaedic injuries and other procedures should be raised. Monitoring for early signs of SAEs for up to 48 h post-intervention is advisable if a SAE is suspected.