Feture Article Chnges in Blood Pressure nd Relted Autonomic Function During Cervicl Trction in Helthy Women CHIEN-TSUNG TSAI, MD; WEN-DIEN CHANG, PHD; MU-JONG KAO, MD; CHUNG-JIEH WANG, MS; PING TUNG LAI, BS bstrct Full rticle vilble online t ORTHOSuperSite.com. Serch: 20110526-08 Cervicl trction is physicl therpy procedure frequently used to tret cervicl disk lesions, cervicl spondylosis, nd cervicl fcet joint lesions. We hve observed rre cses of side effects in elderly ptients, but not in women younger thn 30 yers. In this pilot study, 96 young women were rndomly divided into 3 groups to study the effect of cervicl trction with different trction weights on blood pressure, hert rte, hert rte vribility, nd correlted utonomic djustment. Cervicl trction weight used ws 10% of the ptient s body weight in group A (n 32), 20% in group B (n 32), nd 30% in group C (n 32). Assessments of blood pressure, hert rte, hert rte vribility, percentge of high- nd low-frequency signls, nd low-frequency/high-frequency rtio were performed before, during, nd 20 minutes fter trction. We found tht systolic blood pressure, distolic blood pressure, nd hert rte vribility elevted during cervicl trction nd returned nerly to originl levels immeditely fter trction in group C, but not in groups A or B. There were no significnt chnges in hert rte, percentge of high- or low-frequency signls, nd low-frequency/high-frequency rtio in ll 3 groups during or fter cervicl trction. Cervicl trction with trction weight pproximtely 10% to 20% of body weight cn be sfely provided without significnt compromise of crdiovsculr function. However, hevy trction weight (30% of body weight) should be voided, especilly for ptient with crdiovsculr disese. Figure: Digrm of cervicl trction. Dr Tsi nd Mr Li re from the Deprtment of Rehbilittion Medicine, D-Chien Generl Hospitl, Dr Chng is from the Deprtment of Recretion Sports nd Helth Promotion, Asi-Pcifi c Institute of Cretivity, Mio-Li, Dr Ko is from the Deprtment of Rehbilittion Medicine, Tipei City Hospitl, Tipei, nd Mr Wng is from the Deprtment of Rehbilittion Science, Jen-Teh Junior College of Medicine, Nursing nd Mngement, Mio-Li, Tiwn. Drs Tsi, Chng, nd Ko nd Messrs Wng nd Li hve no relevnt finncil reltionships to disclose. Correspondence should be ddressed to: Wen-Dien Chng, PhD, Deprtment of Recretion Sports nd Helth Promotion, Asi-Pcifi c Institute of Cretivity, No. 110 Syuefu Rd, Toufen Township, Mioli County 351, Tiwn (steven-mndy@yhoo.com.tw). doi: 10.3928/01477447-20110526-08 e295
Feture Article Cervicl trction is physicl therpy procedure frequently used to tret cervicl disk lesions, cervicl spondylosis, nd cervicl fcet joint lesions. 1,2 The proposed mechnisms of therpeutic effectiveness include decresed spsms in the prspinl muscles, incresed opening of intervertebrl formin, incresed intervertebrl disk spce, improved vertebrl lignment, nd improved disk hydrtion. 1,2 However, it hs been reported tht dverse events relted to incresed blood pressure, such s hedche, dizziness, nd nuse, could develop fter cervicl trction. 3 Trction weight my be n importnt fctor in such side effects. Compring different trction weights, Akinbo et l 4 demonstrted tht cervicl trction with weight pproximtely 10% of body weight could provide good relief of neck pin with no significnt dverse effects. Hevy trction weights re usully pplied in tongs trction for cervicl instbility to reduce disloctions/subluxtions. 5 It is likely tht ptients under tongs trction my hve higher incidence of dverse effects thn regulr cervicl trction with lower weight. However, to our knowledge, there hve been no studies on the effects of cervicl trction on crdiovsculr function. It hs been reported tht hert rte vribility could provide importnt informtion bout crdic function in ptients with myocrdil infrction. 6,7 Hert rte vribility refers to the complex bet-to-bet vrition in hert rte produced by the interply of sympthetic nd prsympthetic neurl ctivity t the sinus node of the hert, nd cn provide importnt informtion bout crdiovsculr function relted to utonomic system ctivity. 8,9 In our clinicl prctice, we hve observed rre cses of side effects in elderly ptients, but not in women younger thn 30 yers. In this pilot study, we investigted 96 young women to study the effect of cervicl trction with different trction weights on blood pressure, hert rte, hert rte vribility, nd correlted utonomic djustment. MATERIALS AND METHODS Ninety-six women ged 18 to 23 yers were recruited for this study. They were helthy with no significnt crdiopulmonry diseses, endocrine disorders, neurologicl disorders, musculoskeletl diseses, mentl diseses, or ny other significnt medicl problems. Smokers, hevy drinkers, drug busers, or hevy coffee drinkers were excluded. They were prohibited from consuming ny drug, lcoholic beverge, or coffee within 24 hours prior to the study. They signed the informed consent forms pproved by the Institutionl Review Bord of the university. Ptients were rndomly divided into 3 groups. Cervicl trction weight used ws 10% of the ptient s body weight in group A (n 32), 20% in group B (n 32), nd 30% in group C (n 32). Ptient demogrphic dt re listed in Tble 1. There were no significnt differences in ptient ge, body weight, body height, nd body mss index (BMI) mong the 3 groups. Blood pressure, hert rte, nd hert rte vribility with relted utonomic nervous system function were ssessed before, during, nd immeditely fter cervicl trction with 3 different trction weights in the 3 groups. Prior to cervicl trction, ech ptient st on trction chir with the forerm resting on n rm support in comfortble position. The trction belt ws fixed on the Tble 1 Demogrphic Dt Group A (n 32) Group B (n 32) Group C (n 32) Trction weight, kg 4.8 0.7 9.9 1.0 b 14.4 2.0 c Men ge, y 21.4 1.8 20.9 1.7 21.1 1.5 Men weight, kg 48.0 6.5 9.5 5.2 48.1 6.5 Men height, cm 155.0 4.3 156.0 5.2 154.0 6.2 Men BMI, kg/m 2 20.0 2.7 19.5 2.1 19.8 3.0 Abbrevition: BMI, body mss index. 10% of body weight. b 20% of body weight. c 30% of body weight. hed, then the ptient ws dvised to rest for 5 minutes before the initil ssessment. The initil ssessment lsted for 6 minutes, including 1 minute of blood pressure nd hert rte mesurement followed by 5 minutes of hert rte vribility nd relted utonomic nervous system function. The second ssessment ws performed beginning 10 minutes fter trction for nother 6 minutes. Cervicl trction ws continuously performed for totl of 20 minutes. Immeditely fter trction, post-trction ssessment ws performed for nother 6 minutes. The sequence of the procedure is shown in Figure 1. Cervicl trction ws performed with n electriclly controlled trction unit (Eltrc 471; Enrf-Nonius, Rotterdm, Netherlnds). As soon s the initil ssessment ws completed, the hed belt ws connected to the trction cble t 20 to 30 flexion ngle (Figure 2). The trction cble connected to the trction mchine mintined continuous cervicl trction for 20 minutes in ech experiment. During trction, the ptient mintined comfortble sitting position on trction chir reclined to 100 (Figure 2). The trction procedure could be discontinued immeditely if the ptient felt ny discomfort. Ech trction procedure ws performed by the sme investigtor (W.D.C.). The ptients were not informed bout the trction weight they received. e296 ORTHOPEDICS ORTHOSuperSite.com
BLOOD PRESSURE CHANGES IN CERVICAL TRACTION TSAI ET AL Chnges in blood pressure nd hert rte were mesured on the rm with n electronic sphygmomnometer (ET-SP302; Terumo, Tokyo, Jpn). Dt on systolic blood pressure, distolic blood pressure, nd hert rte from 3 the ssessments were recorded for the clcultion of men nd stndrd devition for further nlysis. Hert rte vribility, high-frequency (HF) signls (0.15-0.4 Hz), low-frequency (LF) signls (0.04-0.15 Hz), nd low-frequency/high-frequency rtios were nlyzed ccording to the guidelines of the Tsk Force of the Europen Society of Crdiology nd the North Americn Society of Pcing nd Electrophysiology 10,11 using electrocrdiogrphy (Check-My-Hert; Dily-Cre Bio-Medicl, Chungli, Tiwn) for 5 minutes nd nlyzed with hert rte vribility nlysis softwre. Hert rte vribility dt were obtined by clcultion of the stndrd devition of R-R intervls on electrocrdiogrm. Percentge of high-frequency signls ws clculted s HF power/(hf power LF power) nd percentge of low-frequency signls ws clculted s LF power/(hf power LF power). High-frequency percentge indictes crdiovgl ctivity 8,9,12,13 nd low-frequency percentge indictes crdiosympthetic ctivity. 8,9 Therefore, the low-frequency/high-frequency rtio represents utonomic blnce. 14 Sttisticl nlysis ws performed using SPSS softwre (SPSS Inc, Chicgo, Illinois). The differences in demogrphic informtion mong 3 groups, including ge, body weight, body height, nd BMI, were nlyzed with the nonprmetric Mnn-Whitney U test. Differences in blood pressure, hert rte, hert rte vribility, high- nd low-frequency signls, nd lowfrequency/high-frequency rtios mong the 3 mesurements were nlyzed with nlysis of vrince. A P vlue.05 ws considered sttisticlly significnt. RESULTS Chnges in Blood Pressure Chnges in blood pressure during nd fter cervicl trction in ech group re shown in Figures 3 nd 4. There were no significnt chnges (P.05) in either systolic or distolic blood pressure during or fter trction in 1 Figure 1: Study procedure. 2 Figure 2: Digrm of cervicl trction. 3 4 Figure 3: Chnges in systolic blood pressure. Figure 4: Chnges in distolic blood pressure. e297
Feture Article groups A nd B. In group C, either systolic or distolic blood pressure ws significntly higher (P.05) during trction thn before trction, but ws not significntly different immeditely fter trction compred to before trction (Tble 2). Tble 2 Blood Pressure Chnges Chnges in Hert Rte Tble 3 nd Figure 5 show the chnges in hert rte during nd fter cervicl trction in ech group. There were no significnt chnges (P.05) in hert rte during or fter trction in ll 3 groups. Men systolic blood pressure, mm Hg Before trction 104.6 6.7 105.9 9.2 102.8 5.3 During trction 103.8 6.8 110.6 6.6 121.4 11.6 After trction 99.3 10.8 106.4 8.7 110.9 10.9 Men distolic blood pressure, mm Hg Before trction 64.0 3.8 66.4 2.4 66.4 3.9 During trction 63.9 5.0 69.5 6.9 78.5 7.6 After trction 65.4 2.6 66.1 6.9 69.4 5.8 Comprison of dt before, during, nd fter trction bsed on nlysis of vrince. Chnges in Hert Rte Vribility There were no significnt chnges in hert rte vribility during nd fter cervicl trction in groups A nd B. However, in group C, hert rte vribility ws significntly lrger (P.05) during trction thn before trction, but ws not significntly different thn before trction (Tble 4; Figure 6). Chnges in Autonomic Functions Chnges in utonomic nervous system function (including high- nd low-frequency signls nd low-frequency/high-frequency rtios) were insignificnt (P.05) during nd fter cervicl trction in ll 3 groups (Tble 5; Figures 7, 8). DISCUSSION In this pilot study on young helthy women, we found tht cervicl trction with constnt weight of pproximtely 30% of body weight could cuse significnt increses in both systolic nd distolic blood pressure during cervicl trction but return to lmost originl levels immeditely fter trction. There ws lso significntly lrger hert rte vribility during cervicl trction thn before trction. These chnges could not be observed during trction with weight of either 20% or 10% of body weight. Chnges in hert rte nd relted Tble 3 Hert Rte Chnges Men hert rte, bets/min Before trction 79.9 13.5 72.9 7.6 82.6 20.3 During trction 77.8 13.0 72.3 8.3 70.3 7.6 After trction 75.6 10.4 73.1 8.5 78.5 13.5 Comprison of dt before, during, nd fter trction bsed on nlysis of vrince. 5 Figure 5: Chnges in hert rte. e298 ORTHOPEDICS ORTHOSuperSite.com
BLOOD PRESSURE CHANGES IN CERVICAL TRACTION TSAI ET AL Tble 4 Hert Rte Vribility Chnges Men hert rte vribility, ms Before trction 48.8 19.6 46.3 15.0 48.3 19.2 During trction 47.8 15.2 47.1 13.4 68.3 13.1 After trction 53.6 16.9 45.3 14.4 59.3 12.5 Comprison of dt before, during, nd fter trction bsed on nlysis of vrince. 6 Figure 6: Chnges in hert rte vribility. utonomic nervous system function were ll insignificnt during cervicl trction with ll 3 weights. Chnges in Blood Pressure Relted to Cervicl Trction In previous study, Utti et l 3 found increses in both systolic blood pressure (from 114.6 10.4 to 123.5 9.8 mm Hg) nd distolic blood pressure (from 72.4 9.5 to 77.9 8.9 mm Hg) fter cervicl trction with 10% of body weight. In our study, no significnt chnges in blood pressure were found when 10% or 20% of body weight ws used for cervicl trction (P.05). This is likely due to the men body weight in our ptients, which ws much lower thn tht in Utti et l s study. 3 The reversible chnges in blood pressure due to cervicl trction with hevy weight (30% of body weight) my be relted to vrious fctors, including direct stretching to broreceptors in the crotid sinus during trction to elicit broreflex 15 ; direct stretching to muscles, tendons, nd ligments to cuse stress-relted sympthetic reflex (physicl stress); nd psychologicl irritbility (mentl stress). It ppers tht the high trction weight (30% of body weight) pplied directly on the chi could cuse significnt stress to cuse pin nd increse in sympthetic tone, so tht the blood pressure ws incresed during trction. Chnges in Hert Rte Relted to Cervicl Trction Theoreticlly, n increse of blood pressure cn cuse broreflex to reduce hert rte nd to cuse utonomic djustment. 16 However, we observed no chnges in hert rte in response to blood pressure chnges. It my be due to smll smple size. An increse of hert rte fter cervicl trction ws found in previous study. 3 Further study on lrger smple is required to clrify this discrepncy. Chnges in Autonomic Function Relted to Cervicl Trction We observed n increse in hert rte vribility during trction with hevy weight (30% of body weight) in response to the elevted blood pressure. However, regrding this increse in utonomic djustment, we were unble to clerly distinguish whether these chnges were relted to sympthetic djustment or vgl djustment. In our study, we found n increse in percentge of high-frequency signls, decrese in percentge of low-frequency signls, nd decrese in low-frequency/ high-frequency rtios during cervicl trction with hevy weight, which might suggest higher vgl ctivity during trction. However, these chnges were not sttisticlly significnt, probbly due to the smll smple size. Hert rte vribility cn be ffected by ge, sex, ethnicity, nd posture. 17-19 Previous studies hve suggested tht women hve predominnt vgl control on crdic regultion 20 nd weker sympthetic control on blood pressure thn men. 21 CONCLUSION It ppers to be sfe, in terms of crdiovsculr function, to pply the usully recommended trction weight (10% to 20% of body weight) for cervicl trction. The dverse symptoms relted to cervicl trction in clinicl prctice re probbly not directly relted to the compromise of crdiovsculr function nd could be due to other cuses, such s tension of cervicl prspinl muscles or pressure to musculoskeletl structures in the chin region such s the jw or temporomndibulr joints from trction belts. However, hevy trction weight ( 30% of body weight) should be pplied with cution since blood pressure cn be elevted during trction. It should be voided in ptient with crdiovsculr disese. Further study on lrger smple of different ge groups is required to confirm these findings. e299
Feture Article Tble 5 High-Frequency Signl, Low-Frequency Signl, nd Low-Frequency/High-Frequency Rtio Chnges Men high-frequency signl, % Before trction 40.5 19.2 47.9 22.9 45.6 15.6 During trction 40.4 22.7 45.6 19.2 56.6 12.9 After trction 51.5 24.5 41.4 22.0 42.8 23.2 Men low-frequency signl, % Before trction 59.5 19.2 52.1 22.9 54.4 15.6 During trction 59.6 22.7 54.4 19.2 43.4 12.9 After trction 48.5 24.5 58.6 22.0 57.3 23.2 Low-frequency/ high-frequency rtio Before trction 2.01 1.41 1.97 2.25 1.46 0.95 During trction 7.44 16.82 1.57 1.09 0.85 0.45 After trction 1.47 1.33 2.45 2.42 2.39 2.45 Comprison of dt before, during, nd fter trction bsed on nlysis of vrince. REFERENCES 1. Grhm N, Gross AR, Goldsmith C; Cervicl Overview Group. Mechnicl trction for mechnicl neck disorders: systemtic review. J Rehbil Med. 2006; 38(3):145-152. 2. Kekosz VN, Hilbert L, Teppermn PS. Cervicl nd lumbopelvic trction. To stretch or not to stretch. Postgrd Med. 1986; 80(8):187-194. 3. Utti VA, Ege S, Lukmn O. Blood pressure nd pulse rte chnges ssocited with cervicl trction. Niger J Med. 2006; 15(2):141-143. 4. Akinbo SR, Noronh CC, Oknlwon AO, Dnesi MA. Effects of different cervicl trction weights on neck pin nd mobility. Niger Postgrd Med J. 2006; 13(3):230-235. 5. Prd SA, Arrington ED, Kowlski KL, Molinri RW. Unilterl cervicl fcet disloction in 9-yer-old boy. Orthopedics. 2010; 33(12):929. doi: 10.3928/01477447-20101021-31. 6. Whb A, Zheer MS, Rbbni MU, Whb S. A study of hert rte vribility nd QT dispersion in ptients of cute ST elevtion myocrdil infrction. Indin Hert J. 2009; 61(3):261-264. 7. Mestri R, Rczk G, Dnilowicz-Symnowicz L, et l. Relibility of hert rte vribility mesurements in ptients with history of myocrdil infrction. Clin Sci (Lond). 2009; 118(3):195-201. 8. Wu JH, Chen HY, Chng YJ, et l. Study of utonomic nervous ctivity of night shift workers treted with lser cupuncture. Photomed Lser Surg. 2009; 27(2):273-279. 9. Stein PK, Bosner MS, Kleiger RE, Conger BM. Hert rte vribility: mesure of crdic utonomic tone. Am Hert J. 1994; 127(5):1376-1381. 10. Hert rte vribility. Stndrds of mesurement, physiologicl interprettion, nd clinicl use. Tsk Force of the Europen Society 7 8 Figure 7: Chnges in high-frequency (HF) signl. Abbrevition: CI, confi dence intervl. Figure 8: Chnges in low-frequency (LF) signl. Abbrevition: CI, confidence intervl. e300 ORTHOPEDICS ORTHOSuperSite.com
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