Professional issue. Guidance for pre-manipulative testing of the cervical spine

Vascular flow limitations affecting the cervico-cranial region: Understanding ischaemia

BACKGROUND

Blood flow and brain ischaemia have been of interest to physical therapists for decades. Despite much debate, and multiple publications around risk assessment of the cervical spine, more work is required to achieve consensus on this vital, complex topic. In 2020, the International Federation of Orthopaedic Manipulative Physical Therapists (IFOMPT) Cervical Framework adopted the dubious terminology 'vascular pathologies of the neck', which is misleading, on the premise that 1) not all flow limitations leading to ischaemia, are associated with observable blood vessel pathology and 2) not all blood flow limitations leading to ischaemia, are in the anatomical region of the 'neck'.

OBJECTIVE

This paper draws upon the full body of haemodynamic knowledge and science, to describe the variety of arterial flow limitations affecting the cervico-cranial region.

DISCUSSION

It is the authors' contention that to apply clinical reasoning and appropriate risk assessment of the cervical spine, there is a requirement for clinicians to have a clear understanding of anatomy/anatomical relations, the haemodynamic science of vascular flow limitation, and related pathologies. This paper describes the wide range of presentations and haemodynamic mechanisms that clinicians may encounter in practice. In cases with a high index suspicion of vascular involvement or an adverse response to assessment/intervention, appropriate referral should be made for further investigations, using consistent terminology. The term 'vascular flow limitation' is proposed when considering the range of mechanisms at play. This fits the terminology used (in vascular literature) at other anatomical sites and is understood by medical colleagues.

Proposing a new algorithm for premanipulative testing in physical therapy practice

In the field of physical therapy, there is debate as to the clinical utility of premanipulative vascular assessments. Cervical artery dysfunction (CAD) risk assessment involves a multi-system approach to differentiate between spontaneous versus mechanical events. The purposes of this inductive analysis of the literature are to discuss the link between cervical spine manipulation (CSM) and CAD, to examine the literature on premanipulative vascular tests, and to suggest an optimal sequence of premanipulative testing based on the differentiation of a spontaneous versus mechanical vascular event. Knowing what premanipulative vascular tests assess and the associated clinical application facilitates an evidence-informed decision for clinical application of vascular assessment before CSM.

Spinal cord injury following chiropractic manipulation to the neck

Spinal cord injury is a rare complication of chiropractic treatment. This case report describes a 50-year-old man who developed neurological symptoms a few hours after manipulation (high velocity low amplitude [HVLA] technique) of the cervical spine. Magnetic resonance (MR) imaging of the cervical spine revealed intramedullary high signal at the C2/3 level of the right side of the cervical cord on the T2-weighted images. The potential mechanism of injury and causes of the radiological appearance are discussed.

Partial tetraplegic syndrome as a complication of a mobilizing/manipulating procedure of the cervical spine in a man with Forestier's disease: a case report

INTRODUCTION

Even if performed by qualified physical therapists, spinal manipulation and mobilization can cause adverse events. This holds true particularly for the cervical spine. In light of the substantial risks, the benefits of cervical spine manipulation may be outweighed by the possibility of further injury.

CASE PRESENTATION

We present the case of a 56-year-old Caucasian man with Forestier's disease who went to see a physiotherapist to relieve his aching neck while on a holiday trip. Following the procedure, he was transferred to a local hospital with a partial tetraplegic syndrome due to a cervical 6/7 luxation fracture. Reportedly, the physiotherapist took neither a detailed history, nor adequate diagnostic measures.

CONCLUSIONS

This case highlights the potentially dangerous complications associated with cervical spine mobilization/manipulation. If guidelines concerning cervical spine mobilization and manipulation practices had been followed, this adverse event could have been avoided.

Current understanding of the relationship between cervical manipulation and stroke: what does it mean for the chiropractic profession?

The understanding of the relationship between cervical manipulative therapy (CMT) and vertebral artery dissection and stroke (VADS) has evolved considerably over the years. In the beginning the relationship was seen as simple cause-effect, in which CMT was seen to cause VADS in certain susceptible individuals. This was perceived as extremely rare by chiropractic physicians, but as far more common by neurologists and others. Recent evidence has clarified the relationship considerably, and suggests that the relationship is not causal, but that patients with VADS often have initial symptoms which cause them to seek care from a chiropractic physician and have a stroke some time after, independent of the chiropractic visit.This new understanding has shifted the focus for the chiropractic physician from one of attempting to "screen" for "risk of complication to manipulation" to one of recognizing the patient who may be having VADS so that early diagnosis and intervention can be pursued. In addition, this new understanding presents the chiropractic profession with an opportunity to change the conversation about CMT and VADS by taking a proactive, public health approach to this uncommon but potentially devastating disorder.

Upper cervical ligament testing in a patient with os odontoideum presenting with headaches

STUDY DESIGN

Resident's case problem.

BACKGROUND

The role of premanipulative testing of the cervical spine is an area of controversy, and there are very few data to inform and guide practitioners on the use of ligamentous stability tests when assessing the upper cervical spine.

DIAGNOSIS

A 23-year-old female was referred to physical therapy by a neurologist for the management of intractable headaches of possible musculoskeletal origin. Her Neck Disability Index score was 54% and she rated her headache pain from 3/10 to 9/10 on a Numerical Pain Rating Scale. She reported a 2-year history of intermittent lower extremity paresthesias without a known mechanism or current symptoms. She was treated in physical therapy for 11 visits with improvements in cervical range of motion, strength, and intensity of her headaches, but noted no change in the frequency of headaches. She was subsequently referred to the primary author for a second opinion and potential manual therapy interventions. Initial neurological screening examination for upper and lower motor neuron lesions was unremarkable. Assessment of the transverse ligament, using the anterior shear test in supine, brought on paresthesias in both feet and her toes. The paresthesias continued after the cessation of the test. The Sharp-Purser test performed in sitting, immediately after the transverse ligament test, abolished the paresthesias. She was then referred back to her primary care physician for further evaluation. Subsequent radiographs and magnetic resonance imaging revealed that the patient had a C2-C3 Klippel-Feil congenital fusion and os odontoideum. The patient was examined by a neurosurgeon who concluded that she was not a surgical candidate. Her neurological symptoms completely resolved, but she continued to have headaches.

DISCUSSION

Os odontoideum is a clinically important condition, given that the mobile dens may render the transverse ligament incompetent, leading to atlantoaxial instability. Both the role and sequencing of upper cervical ligamentous testing is controversial. The results of this case report suggest that physical therapists should be cognizant of this condition and consider screening the upper cervical ligaments prior to manual or mechanical interventions to this region.

LEVEL OF EVIDENCE

Differential diagnosis, level 4.

Pre-manipulative testing and the use of the velocimeter

Manipulation of the cervical spine remains a common intervention for neck pain and dysfunction, despite the well-documented associated risk of vertebrobasilar stroke. The currently advocated pre-manipulative risk assessment protocols include the use of provocative positional tests to challenge the integrity of the vascular supply to the brain. This paper critically evaluates the validity of these pre-manipulative provocative tests in the light of ultrasonographic blood flow studies of the vertebral arteries. It also critically evaluates the evidence concerning the clinical utility of a portable continuous wave Doppler device (or velocimeter) to examine vertebral artery blood flow prior to neck manipulation. There is clear evidence that the provocative tests may produce both false positive and false negative findings. Initial research regarding the clinical use of a velocimeter suggests this device may provide a more objective assessment of vertebral artery blood flow than the provocative tests. However, the sensitivity, specificity and reliability of the use of the velocimeter in identifying abnormal vascular flow in the vertebral arteries, and therefore its clinical utility, has not yet been fully established.

Relationship between the Duplex Doppler Ultrasound and a Questionnaire Screening for Positional Tolerance of the Cervical Spine in Subjects with Suspected Vascular Pathology: A Case Series Pilot Study

Manual therapy healthcare practitioners routinely perform the vertebral artery test (VAT) to determine cervical positional tolerance and to screen for vertebrobasilar insufficiency (VBI) prior to manipulating the cervical spine. Because the safety and validity of the VAT has been questioned in the literature, the purpose of this study was to determine if a relationship existed between a new tool, the cervical positional tolerance questionnaire (CPTQ), and the duplex Doppler ultrasound findings for patients with suspected VBI. Subjects were 39 consecutive patients referred by their physician for a duplex Doppler ultrasound with suspicion of VBI. On the CPTQ, patients reported whether they avoided certain cervical positions due to symptoms consistent with VBI prior to undergoing the ultrasound. The CPTQ had a sensitivity = 1.00 (95% CI: 0.34-1.00); specificity = 0.78 (95% CI: 0.64-0.92); negative likelihood ratio = 0.00 (95% CI: 0.02-2.73); and positive likelihood ratio = 4.50 (95% CI: 1.67-7.89). The results of this case series study, while preliminary, are encouraging. Further research with larger sample sizes is warranted in the development of the CPTQ regarding pre-cervical manipulation clinical decision-making. Inclusion of subjects from a cohort including asymptomatic people (no suspicion of VBI) would also strengthen the screening ability of the CPTQ. In addition to duplex Doppler ultrasound, using a gold standard test of vertebral artery testing by way of magnetic resonance angiography (MRA) would further improve data on the diagnostic utility of the CPTQ.

Is it time to stop functional pre-manipulation testing of the cervical spine?

The combined extended and rotated cervical spine position has been postulated to affect vertebral artery blood flow by primarily causing a narrowing of the vessel lumen, usually within the artery contralateral to the side of head rotation. The production of brainstem symptoms during the manoeuvre has generally been considered to be a positive test result. As a consequence, functional pre-manipulation testing of the cervical spine has been part of clinical screening undertaken by chiropractors and other manual practitioners to rule out the risk of possible injury to the vertebral artery. To date, these testing procedures are taught to students and carried out in daily clinical practice, despite the considerable controversy that exists about their validity. This paper considers and discusses the usefulness of functional pre-manipulation testing for clinical scenarios, involving dissection, spasm or stenosis of the vertebral artery, and makes the following recommendations: (1) Practitioners must assess the patient thoroughly, through careful history taking and physical examination, for the possibility of vertebral artery dissection. It is important to note that vertebral artery dissection (VAD) may present as pain only, and may not be associated with symptoms and signs of brainstem ischaemia. (2) If there is a strong likelihood of VAD, provocative pre-manipulation tests should not be performed, and the patient must be referred appropriately. (3) In the patient presenting with symptoms of brainstem ischaemia due to non-dissection stenotic vertebral artery pathologies, provocative testing is very unlikely to provide any useful additional diagnostic information. (4) In the patient with unapparent vertebral artery pathology, where spinal manipulative therapy (SMT) is considered as the treatment of choice, provocative testing is very unlikely to provide any useful information in assessing the probability of manipulation induced vertebral artery injury.

Screening for vertebrobasilar insufficiency in patients with neck pain: manual therapy decision-making in the presence of uncertainty

Growing evidence supports the effectiveness of manual therapy interventions in patients with neck pain; however, considerable attention has also been afforded to the potential risks such as vertebrobasilar insufficiency (VBI). Despite the existence of guidelines advocating specific screening procedures, research does not support the ability to accurately identify patients at risk. The logical question becomes, "How does one proceed in the absence of certainty?" Given the lack of clear direction for decision making in the peer-reviewed literature, this commentary discusses the uncertainties that exist regarding the ability to identify patients at risk for VBI. The authors hope that this commentary adds additional perspective on manual therapy decision-making strategies in the presence of uncertainty.

Is cervical spine rotation, as used in the standard vertebrobasilar insufficiency test, associated with a measureable change in intracranial vertebral artery blood flow?

Cervical spine rotation is used by manual therapists as a premanipulative vertebrobasilar insufficiency (VBI) test to identify patients at risk of developing VBI post-manipulation. Investigations of the effect of rotation on vertebral artery blood flow have yielded conflicting results, the validity of the test being debated. It was the aim of this study, therefore, to investigate the effects of cervical spine rotation on vertebral artery blood flow. Transcranial Doppler sonography was used to measure intracranial vertebral artery blood flow in 30 young, healthy, female subjects, with the cervical spine in the neutral position and with sustained, end-of-range rotation. Statistically significant decreases in blood flow were demonstrated with contralateral rotation particularly, in the left (45.9+/-8.5 to 41.8+/-11.6 cm/s) and right (27.8+/-6.9 to 25.2+/-8.2 cm/s) vertebral arteries. Despite this change in blood flow, signs and symptoms of VBI were not demonstrated in these subjects. Nevertheless, these findings are of clinical importance, especially in patients who may have underlying vascular pathology. Thus, this study supports the use of the VBI test, in the absence of a more specific, sensitive and valid test, to assess the adequacy of hindbrain blood supply to identify those patients who may be at risk of serious complications post-manipulation.

Spinal manipulative thrust technique using combined movement theory

Spinal Manipulative Thrust Technique (SMTT) is employed by all manual therapy professions using different rationales for the selection of technique. A method of rationally selecting particular SMTT's is described with a view to integrating SMTT into the practice of manual therapists familiar with Combined Movement Theory (CMT), a corollary of the Maitland Concept. The similarities of CMT and SMTT methodologies are described and two examples of how CMT can be utilized for SMTT selection in the cervical spine are detailed.