Cervical Manipulation 

Cervical ROM Assessment: Is One Method Better than Another?

Research on range-of-motion (ROM) often utilizes so many measuring instruments and statistical analyses that it can be difficult to select suitable instruments, procedures and normative values to apply in the clinical setting.

Although ROM reviews have detailed various measurement methods for the cervical spine and have included brief reviews of the literature, the authors contend that no previous study has served as a "comprehensive synthesis of the normative cervical ROM literature."

Studies were included in this review if they reported ROM values, variability or reliability using asymptomatic subjects, or if they represented a specific type of study known as a concurrent validity study. ROM and data regarding the reliability of ROM procedures were grouped by technology and types of motion; clinical validity was assessed; and changes in ROM as a function of age were determined by comparing decade ratios.

Nine different technologies for assessing ROM were identified in the review. Variations within each technology were as large as (or larger than) those between technologies, which the authors suggest may indicate that clinical procedures are as important as the accuracy and precision of the technology itself. Additionally, passive motion was determined to be greater than active motion, and range of motion decreased as age increased (with women exhibiting greater ROM than men). The authors noted that reliability was not adequately tested for the majority of technologies reviewed.

The authors suggest that "...practitioners limit their selection of instruments and the types of motion to those that have demonstrated good reliability." They offer examples such as single inclinometry for assessing active motions and potentiometry for measuring static and dynamic ROM of active and passive motions.

Cervical or Sacroiliac Manipulation Increases Hip ROM

For some, it is controversial to propose that spinal manipulation can be directed for treatment of peripheral joints. Yet practitioners within several manual therapy professions strongly support these approaches.

The objective of this study was to compare the effectiveness of upper cervical spine (C/S) manipulation with manipulation of the sacroiliac joint (SIJ) for increasing hip range of motion (ROM).

At the Macquarie University Centre for Chiropractic Outpatient Clinic, 52 randomly chosen students (aged 18-34) were divided into three groups: those receiving C/S manipulation, those undergoing SIJ manipulation, and those placed in a sham/placebo group.

Manipulation of the C/S and SIJ increased flexion of the hip. But only the upper cervical treatment produced a statistically significant increase. Moreover, post-treatment increases in the cervical group were significantly greater than post-treatment changes seen in the sacroiliac group.

Part of the authors' report stated that "a single manipulation of the first vertebra of normal university students statistically improved hip flexion ROM. By contrast, a single manipulation of the sacroiliac joint did not statistically improved hip flexion ROM in the same population of subjects."

These findings suggest that there is a link between the cervical spine and the lower extremity and that manipulation of the upper cervical area may significantly affect hip ROM and thus play a role in conditions that cause loss of hip ROM. This is the second paper reviewed in this issue of the CRR that discusses the peripheral effects of spinal manipulation. See the first summary for the other paper.

Cervical Manipulation in Extreme Rotation and Extension: Just Say No!

Middle-aged and elderly patients frequently present with cervical spondylotic syndrome. The objective of this study was to obtain experimental and clinical data on the effects of neck extension and extension-rotation of the head on the blood flow of the vertebral artery.

The study was conducted at the Institute of Clinical Anatomy and Biomechanics and the Department of Ultrasound, NanFang Hospital of the First Military University, Guangzhou, China

The investigators examined 3 groups of subjects; 10 fresh spines (T1-2 to the occiput) taken from individuals who had suffered acute brain death, 27 elderly asymptomatic patients, and 23 university students. The investigators observed the dissected spines to see if there was a drop in pressure in the vertebral artery during extreme extension and rotation of the spine. The patients were observed for changes in blood flow velocities during the same movement.

The results indicate that blood flow in the veterbral arteries can be dangerously reduced during cervical manipulation. Since rotary manipulation is one of the oldest and most widely used forms of manual medicine, chiropractors should take special pains to ensure that what they consider appropriate conservative management does not lead to the sorts of damaging complications the results of this study describe.

Conclusions, with a warning: "Extreme extension and extension-rotation of the head should be avoided during cervical manipulation in most patients.� This is because extreme extension-rotation of the head can produce a greater effect on the velocities in the vertebrobasilar arteries than simple extension of the head. �Doctors should be especially careful when rotating the patient�s head to the right side." 

Vertebral Artery Volume Flow: No Change with Rotation or Spinal Manipulation

The vertebral artery is a source of great interest to chiropractors because of its intimate relationship with the cervical vertebrae and because of concern of cerebrovascular complications following spinal manipulation.

Previous studies have quantified blood flow velocity, but few, if any, have investigated vertebral artery volume flow during cervical rotation.

To remedy this deficiency, a study involving 20 students utilized advanced color-coded duplex sonography to assess volume flow through the right vertebral artery. Measurements were taken in the neutral position, during 45° of rotation and at maximal rotation. Subjects were then randomized to a control group or a group that received spinal manipulation of a biomechanical dysfunction of the cervical spine, and volume blood flow was again measured, 3, 10 and 15 minutes after the intervention.

Results: Sonogram analysis revealed no significant difference in volume blood flow with cervical rotation or spinal manipulation, despite changes in flow velocity. 

Chiropractic Technique and the Occipitoatlantal Joint

The occipitoatlantal (OA) joint is the most superior weight-bearing synovial joint in the body. Because the OA articulation is one of the final locations at which the body can adapt to asymmetry or dysfunction below, the author contends that this joint requires evaluation in the context of the entire body.

This article presents a concise physical evaluation process for the OA joint complex and discusses some of the more prominent clinical findings indicative of dynsfunction, particularly as they relate to the "integrated manual care" approach presented by the author. Manual treatment processes are also presented to help clinicians manage dysfunctional findings. Evaluation procedures discussed include:

* postural assessment;

* muscle and joint manual palpation techniques;

* range-of-motion testing; and

* anterior-posterior and lateral gliding tests.

Treatment methods upon finding OA dysfunction are organized around clinical findings of the examination. The author suggests:

* positional release;

* direct methods (low velocity, muscle energy, high velocity);

* myofascial release; and

* general techniques (ischemic compression, isometric contractions, deep stroking massage, friction, etc.).

This paper presents the author's approach to managing OA problems. As he notes, these concepts present practitioners with a variety of methods to manage this part of the spine. Elementary evidence, such as case reports or case series, have not yet been presented to describe relevant clinical scenarios or patient reactions to care. 

Discovery of Dural Attachments in the Cervical Spine

The cervical spine is stabilized posteriorly by the ligamentum nuchae and other ligaments. While previous research has described the ligamentum nuchae in general terms, this study attempted to describe more detailed attachments to the cervical posterior spinal dura and to posterolateral parts of the occipital bone.

Ten heads from embalmed cadavers were sectioned to reveal the ligamentum nuchae and its connection to the cervical posterior spinal dura, allowing for particular attention and reference to the deep aspects of the suboccipital triangle and upper cervical region.

In the midline between the first and second cervical vertebrae, researchers found a fibroelastic ligamentous attachment to the cervical posterior spinal dura derived from the ligamentum nuchae. As the ligamentum passed cranially, part of it passed bilaterally to the posterior aspect of the base of the occipital bone, as far superiorly as the inferior nuchal line and as far laterally as the sutures with the temporal bones.

This study reveals a more complex morphology of the ligamentum nuchae than has previously been described. The bilateral attachments of the nuchae to the occipital bone reaffirm its role in stabilizing the head during rotation of the cervical spine. These findings may have implications in the understanding of facial and cervical pain and associated disorders. 

Mysteries of Cervical Uncovertebral Joint Function Revealed

The cervical uncovertebral joint consists of the uncinate process and its corresponding recess located on the surface of the upper vertebral body. Because osseous spurs in this region can cause cervical radiculopathy, understanding the biomechanical role of these joints may assist clinicians in better treating their patients.

In this study, 14 human cadaver specimens underwent sequential uncovertebral joint resection.

At each stage of resection the joints were analyzed for function, including torsion, flexion, extension and lateral bending, and several conclusions drawn:

* Different subdivisions of the uncovertebral joints may have different biomechanical contributions.

* Statistically significant differences can be observed in different locations of the spine.

* The major biomechanical function of the uncovertebral joints includes the regulation of extension and lateral bending motion, followed by torsion.

Although this study sought to clarify the biomechanical role of uncovertebral joints in cervical segmental stability relating to the surgical setting, the information presented can help all health care professionals to better understand the function of these joints as it relates to patient care.

Blood Pressure Influenced by Upper Cervical Adjustments

Several theories have been suggested for the effects of manipulative treatment and arterial blood pressure (BP). Subluxation and musculoskeletal dysfunction in spinal segments may result in stimulation of sympathetic tone, which may cause vasoconstriction and result in a rise of systemic BP.

Other theories include the effects of manipulation and changes in hormone levels, vestibulosympathetic and cervicosympathetic reflexes which alter BP, and the pressor reflex.

This two-part study attempted to determine whether a vectored adjustment of the atlas would cause a lowering of blood pressure. Eighty patients were evaluated by palpation, for BP (using a digital oscillometric sphygmomanometer) and for signs of pelvic rotation and a supine leg length check. Forty patients demonstrating signs of upper cervical subluxation were designated to the treatment group and 40 patients without such signs were assigned to the control group. Sideposture and upper cervical adjustments were performed on the participants in the treatment group. The control group patients were positioned in side posture but not adjusted. After two minutes BP was checked again. In the second part of this study, only patients with postural distortion were recruited. Pre-adjustment measurements with the patient in the supine and sitting positions were used as 'control' data, which was compared to the BP measurements taken after the upper cervical adjustment.

The results for both portions of this trial show significant differences between pretreatment and post treatment measurements in BP. The results also indicate that palpation and upper cervical adjustments may decrease systolic blood pressure, although it is uncertain how long this effect lasts. The authors recognize the weaknesses of this study, including the lack of blinding, repeated BP checks without adequate time for stabilization and no randomization. This article provides an interesting discussion on some of the possible theories that may explain the phenomenon of BP changes with upper cervical adjustments.