Alo

ChiropracticAnd The

VertebralArteries

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Thomas Siever~ D.C.Roy W Swea~ D.C.

Roy W. Sweat, D.C.Thomas Sievert. D.C.

About the Author: Dr. Roy W Sweat'spractice is in Atlanta, Georgia. He isa graduate of Palmer College. In1952, he began a course of studyspecializing in the upper cervicaloccipital-atlanta-axial complex. underDr. John F. Grostic. Dr. Grostic chosehim as an instructor at hisseminars. Sweat completed a three-year program in chiropractic ortho-pedics from the National Collegeand is an associate professor at LifeCollege.

Dr. Sweat designed the cervicalanalysis instrument. In 1981 hecreated the program of chiropracticAtlas Orthogonality and wrote aseries of five books. Dr. Sweat hasdesigned a chiropractic adjusting in-strument and also a series of x-raymachines and the orthogonal adjust-ing tables.

About the Author: Dr. ThomasSievert attended the University ofWisconsin at Eau Claire, and grad-uated magna cum laude from LifeChiropractic College. Dr. Sievert in-terned under Dr. Roy Sweat fromwhom he received special training inorthogonal procedures of cervicaladjustment He also has done postgraduate work in orthopedic testing,personal injuryand impairment rating.Dr. Sievert is a diplomate of theNational Board of Chiropractic Ex-aminers. He maintains a practice at2060 Collier Avenue, Fort Myers,Fla., 33901.

Anatomical Variants of theVertebral Arteries

Hadley reports that tortuosities ofthe vertebral arteries were found on

Today's Chiropractic/November-December. 1984

dissection in four of twenty-one cases.One case study presented a complete360 degree loop between the trans-verse processes of C3 and C4.

The lower two right angle turns ofthe artery at C2 are common sites foraneurysms, according to Dr. J.A W.Duckworth of the Canadian Chiro-practic College. Hadley also describesan aneurysm-like condition whichoccurs, not uncommonly, within thebody of the second cervical vertebraand can be visualized in both the APand lateral projections. Clinically, thetortuosities of the vertebral arteriesmay render the artery vulnerable tocompressive forces.

Another interesting variation in thevertebral artery is the high incidenceof one artery being predominatelylarger than the other. Dissection of sixbrain stem specimens taken at randomunder the direction of Dr. MaconWeaver at Life Chiropractic Collegerevealed the diameter of the left vesselto be significantly larger than the rightin five of six cases. Leach reportsstudies citing seventy-one cases ofassymetry of the vertebral arteries outof one hundred thirty post-mortemexaminations. He also describes Junsi'sstudy of eighteen patients with onevertebral artery congenitally smallerthan the other: "In every case whereunilateral blockage of the vessel pro-duced symptoms, it was the largerartery which was blocked."Mechanisms of Compression

The mechanisms of compressionof the vertebral artery can occur byextremes of rotation and extension,hyperplastic posterior joints, neuro-central osteophytes, herniation of thenucleus pulposus and subluxations.

Salecki studied the effect of thelarge rotational movements of Cl- C2on the vertebral artery and found that

Part two of two

30 degrees of rotation producedkinking accompanied by stretching ofthe contralateral artery, which becomesmore marked as the angle of rotationis increased. He also found that at 45degrees rotation the ipsilateral verte-bral artery begins to kink If the bloodflow is significantly decreased, symp-toms of ischemia may be elicited.

Effects of extension on the vertebralartery have been cited by MacNaband Duckworth. Spondolytic forma-tions in the mid-cervical spine put thatregion in an attitude of flexion resultingin a compensatory extension of theupper cervical spine to hold the headupright Further extension may pro-duce severe stretching of the vertebralartery between Cl and C2 or Cl andocciput because this will be the onlyarea capable of further extension.Duckworth states that arterioscleroticchanges by way of calcium depositionoccur in the elderly and predisposethe vertebral arteries to injury due totheir inability to stretch on extension.Cases exhibiting these types of de-generative conditions will be moresusceptible to forces that hyperextendthe spine and the ensuing sympto-matology of vertebral artery compro-mise.

Hadley reports that hyperplasticarthrotic posterior joints can producevertebral artery compromise. Exten-sion of the cervical spine allows thesuperior articular facet to move forwardand upward. Hyperplastic posteriorjoints may deflect the vertebral arterywhich will become exaggerated onextension and/or rotation, producinga decreased blood volume and sub-

sequent symptomatology. He alsostates that atheromatous changesoccur in the vessel over a period oftime due to the constant deflection ofthe artery.

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According to MacNab, cervical discdegeneration may also produce com-pression of the vertebral artery. A lossof disc height eventually leads to thejamming together of adjacent neuro-central joints, producing osteophytes.If an osteophytic spur from a neuro-central joint projects laterally, it maycompress the artery as it issues fromthe transverse foramen, resulting invertebral artery symptomatology."Diagnosis

Diagnosis of a suspected vertebralartery syndrome is obtained by thecorrelation of subjective symptoma-tology, case history and objectivefindings on x-ray and examination.Spondolytic deformities, hyperplasticarthrotic posterior joints, osteophyteformations and bone erosions can benoted on lateral AP and obliqueprojection. Suspected compromise ofthe vertebral artery can be verifiedupon physical examination by per-forming George's CerebrovascularCraniocervical Functional Test forIschemia.This test can be done standingor sitting; however, for the patient'ssafety, sitting is recommended. Witheyes closed and arms stretched for-ward, the patient is instructed to rotatethe head to one side and extend theneck, holding for 30 seconds. This

should also be repeated on the op-posite side. Sway of the outstretchedarms suggests cerebral ischemia. Ifthe symptoms of syncope, tinnitus,vertigo, or nausea are elicited, verte-bral artery compromise should besuspected.Conclusion

CHIROPRACTIC'S TIME HASCOME! Nearly all of the diseases andsymptomatic conditions with whichchiropractic has had miraculous resultscan now be documented by themedical profession as being possiblewith causes related to vertebral arteryinsult.

Chiropractic care of the cervicalspine for vertibrobasilar symptoma-tology is necessary and extremelysuccessful.

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References1. VonTorklus. Detlef.The Upper Cervical

Spine, New York. Grule and Stratton, 1972,Page22.

2. WhiteandPanjabi.ClinicalBiomechanicsofthe Spine.Philadelphia. Lippincott, 1978,Page66.3. Hadley, Lee A. Anatomico-Roentgeno-

graphic Studies of the Spine.Springfield.Thomas. 1964, Page162.

4. Epstein, Bernard S. The Spine-A Radio-logical Text and Atlas, Philadelphia. Lea andFebiger, 1962, Pages268-269.5. Kabat, Herman. Low Back and Leg Pain,

St. Louis. Green. 1980, Page 130.6. Rotham and Simeone. The Spine. Phila-

delphia. Saunders, 1982, Pages 193, 456, 652.7. MacNab, (an. The Cervical Spine.

"Symptoms in Cervical Disc Degeneration".Philadelphia. Lippincott, 1983, Pages 388-394.

8. TheCervical Spine Research Society. TheCervical Spine - MacNab."Symptoms inCervical Disc Degeneration", Philadelphia.Lippincott, 1983. Page 392.

9. Selecki. B.H. "The Effects of Rotation ofthe Atlas on the Axis: Experimental Work"Medical Journal, August, 1969. T:I012.10. Duckworth. J.A W. Dissection Seminar.Canadian Memorial Chiropractic College,Toronto. Canada. 1983.11. Weaver. Macon. Dissection Seminar, LifeChiropractic College. Marietta. Georgia. 1984.12. Netter. Frank H. The Ciba Collection ofMedical lllustrations - Volume I "NervousSystem" Published by Ciba. Page 24.13. Wicke,Lothar. Atlas of RadiologicAnatomy- Third Edition. Urban & Schwarzenberg. Page35. Vertebral Arteriogram (A-P Projection)Page 33. Vertebral Arteriogram (Lateral Pro-jection).14. Chusio, J.G. "Correlative Neuroanatomyand Functional Neurology." 16th Edition,Pages 45-46.

Today's Chiropractic/November-December.1984