Hypertension is a major global health concern. It is estimated that 30–40 % of the adult population in the developed world are suffering from hypertension [1, 2]. Moreover, incidence and prevalence of hypertension are increasing, especially in developing countries. The effects of current pharmacologic treatment of hypertension remain suboptimal in both developing and developed countries [3, 4]. The common causes responsible for the poor control of high blood pressure are attributed to physicians’ attitudes and patient non-compliance to lifelong pharmacological therapy for asymptomatic hypertension [5–7]. Moreover, hypertension that remains uncontrolled in spite of the use of 3 or more antihypertensive drugs has been called resistant hypertension [8]. Clinical evidence indicates that the risk of major cardiovascular events is higher among patients with resistant hypertension than that among patients with controlled blood pressure [5]. Thus, developing novel approaches for management of hypertension, especially for resistant hypertension, is an important issue for the future of the treatment of hypertension.

It is well known that sympathetic nerve fibers are rich in cervical spinal tissues [9–11]. Yamada et al. [9] reported that there was different sympathetic innervation between the cervical dura mater and the posterior longitudinal ligament. It seems reasonable that the compression or irritation of cervical dura mater and/or posterior longitudinal ligament may cause an increase in blood pressure or aggravate pre-existing hypertension among patients with cervical spondylosis myelopathy.

Tamura [12] found that neck injury, such as whiplash, may lead to the cranial symptoms of the Barré-Lieou syndrome (including a group of symptoms such as headache, vertigo, tinnitus and ocular problems), which may result from irritation of the sympathetic nervous supply. We hypothesize that the cervical sympathetic nerve is also associated with the occurrence of resistant hypertension and that cervical decompressive surgery may be beneficial in blood pressure control among patients with cervical spondylosis myelopathy [13]. The purpose of this study is to investigate the effect of cervical decompressive surgery on resistant hypertension based on a novel mechanistic hypothesis of essential hypertension.

The etiology and mechanism of essential hypertension remains unclear. Non-operative methods of essential hypertension treatment including antihypertensive pharmacologic drugs are still unsatisfactory [5, 8]. In the past several years, a new procedure named renal denervation had been shown to be safe and effective in controlling hypertension, supporting that the sympathetic nervous system (SNS) activity is critical in regulating blood pressure [6, 7]. Recently, we have proposed a novel hypothesis that cervical spondylotic myelopathy may be an important etiology of essential hypertension which has been termed as cervicogenic hypertension [13]. In our previous study, we found that the high blood pressure in 12 out of 30 (40 %) hypertensive patients was reduced to normal levels following the cervical decompressive surgery, which resulted in a termination of the antihypertensive medications. Furthermore, the high and unstable blood pressure in the other 15 patients became stabilized and was well controlled by antihypertensive drugs after cervical decompressive surgery [13]. Recently, Peng et al. reported two cases of cervical spondylosis with hypertension [15]. After anterior cervical discectomy and fusion, the blood pressure of both the two patients remain normal without hypertensive medications [15]. Also, we speculate that renal denervation only destructs the network of SNS, and that the diseased cervical SNS has a greater impact on initiating and increasing SNS activity, as it may be closer to central nervous system than the normal renal SNS.

Through long–term clinical observations, we have found that high blood pressure or fluctuated blood pressure among many patients decreased substantially or became stable post-operatively. Therefore, we infer that cervical decompressive surgery may be a novel alternative in treating hypertension and will effectively reduce blood pressure in patients with cervicogenic hypertension. Therefore, a substantial number of patients with both hypertension and cervical spondylosis may benefit from this approach as the decrease in the quantity and/or dose of antihypertensive drugs would subsequently lead to fewer side effects from them. Regarding the rationale for the reduction on blood pressure, we speculate that the compression or irritation of the dura mater and the posterior longitudinal ligament of the cervical spine may increase the sympathetic nervous activation. This discharge may pass through the ganglia and the sympathetic trunk to the postganglia fibers arriving at the target organ, such as the vertebral artery and the blood vessels and subsequently induce hypertension. Decompressive cervical surgery, either anterior cervical discectomy and fusion or posterior laminoplasty, may withdraw any compression of the dura and the posterior longitudinal ligament and thus the sympathetic irritation will be relieved leading to a decrease of blood pressure.

Our study has a number of limitations. This is not a randomized controlled clinical trial, factors such as placebo and Hawthorne effects cannot be ruled out entirely. However, we tried to measure blood pressure two times both before and after the surgery, these multiple measurements would help to better understand if the change in blood pressure is attributed to the surgery or purely to the regression to the mean. Although the randomized controlled trial is the gold standard study design, it is unethical to conduct such a trial considering the inappropriateness of treating hypertension with a cervical decompressive surgery. In our opinion, the study still gains important scientific information. Once our hypothesis is approved, it will provide an innovative mechanism of hypertension development, which may lead to the development of new methods of hypertension treatment and prevention.