Do Adjustments/Manipulations cause Strokes?
This is another common topic of conversation I have with patients, particularly new patients, who have never had their neck adjusted/manipulated either based on fear or otherwise. First, the terms adjustment and manipulation can be used interchangeably in relation to the technique, but each describe a different rationale for the treatment.
Adjustments are typically used by chiropractors to ‘re-align’ the spine, referring to the ‘Vertebral subluxation theory’. In short, a vertebrae is ‘out of ‘alignment’ causing issues which needs to be ‘adjusted back into alignment’.
Manipulations are used more commonly by DPTs and DO’s to manipulate joints or segments of the spine in order to improve mobility, range of motion, and reduce muscle tension. Some of the techniques are very similar, if not the same, but the difference is the reason behind performing them.
The most common fear that I hear is the risk of having a stroke following the treatment. After having studied and performing these techniques for years, I know this is possible, but unlikely. And here’s why…
First, there is between a 1 in 400,000 and 1 in 1 million chance of manipulation or an adjustment resulting in a severe complication (Dvorak & Orelli 1985).
OR 1 in 1.3 million (Klougart 1996).
Second, active, voluntary range of motion of the neck (i.e. turning the neck, looking up, etc.) has between 1.2%-12.5% strain placed on the vertebral artery compared to at rest. Compare this to manipulation, which puts only 6.2% strain on the same artery compared to at rest. Meaning, turning your head to check your blind spot before merging puts your vertebral artery at more risk of tearing the artery and possibly resulting in a stroke than a proper manipulation (Symons et al. 2002).
Third, there is an overlap of symptoms, specifically headache and neck pain, between stroke and other diagnoses, for which patients initially seek the help of a healthcare provider. In this article cited below, the authors concluded that the instances in which stroke resulted from a cervical adjustment, those patients were exhibiting signs of a stroke prior to the treatment. Meaning, it is the practitioners responsibility to thoroughly evaluate and determine if the patient is experiencing those symptoms due to a stroke or other cause before performing any sort of treatment (Murphy et al. 2010).
Also, in a case-control and case-crossover study, 818 hospitalized stroke cases were analyzed and found that there was a stronger correlation to primary care physician visits and subsequent stroke compared to that of chiropractic care. This suggests that properly trained physical therapists and chiropractors are better equipped to assess and diagnose the cause of neck pain and headaches and recognize the symptoms of a stroke better than general primary care physicians (Cassidy et al. 2009).
Summary…
1 in 1 million chance (Dvorak & Orelli 1985)
Active movements of the head puts twice the amount of strain on the vertebral artery than properly performed manipulation (Symons et al. 2002)
Most of these documented cases demonstrate signs of stroke prior to receiving any treatment, meaning the stroke was already underway (Murphy et al. 2010)
Stronger correlation to primary care physician visits and subsequent stroke due to reports of head and neck pain compared to that of chiropractic visits and subsequent stroke (Cassidy et al. 2009)
Make sure your practitioner is well trained and well-versed in the realm of cervical adjustments/manipulations and differential diagnosis!!