임상신경생리학회지 도비라.indd

대한임상신경생리학회지 15(1):7~12, 2013 eissn 2288-1026 pissn 1229-6414 Original Article 수근관증후군에서국소스테로이드주사후임상적, 전기생리학적변화 건양대학교병원신경과 1, 건양대학교병원산부인과 2 김지훈 1 이기욱 1 윤보라 1 김용덕 1 정언석 2 나상준 1 Clinical and Electrophysiological Changes after Local Steroid Injection in the Carpal Tunnel Syndrome Jihoon Kim 1, Kee Ook Lee 1, Bora Yoon 1, Yong-Duk Kim 1, Un Suk Jung 2, Sang-Jun Na 1 1 Department of Neurology and 2 Department of Obstetrics and Gynecology, Konyang University Hospital, Daejeon, Korea Background: Local steroid injection is used to treat carpal tunnel syndrome (CTS). The aim of this study was to evaluate the clinical and electrophysiological effects of local steroid injection in patients with CTS over a 3-months period. Methods: Twenty-one patients (35 hands) with clinical and electrophysiological evidence of CTS were treated by injection of triamcinolone 40 mg to the carpal tunnel. Visual analog scale (VAS), Boston Carpal Tunnel Questionnaire (BCTQ), rates of paresthesia, night awakening, and electrophysiological studies were used as outcomes. Clinical and electrophysiological assessments were performed before, 1 and 3 months after treatment. Results: Prior to treatment, 86% of patients complained of night awakening. At 1 and 3 months after injection, only 17% and 29% of the patients, respectively, had night awakening (p<0.001). All patients complained of paresthesia before the treatment. This symptom disappeared in 60% and 31% of the patients after 1 and 3 months, respectively (p<0.001). Compared to baseline, both BCTQ and VAS show significant improvement during the 3 months of the study (p<0.005). Although significant improvements in clinical parameters were shown, electrophysiological parameters were not significantly improved at 1 and 3 months. Conclusions: Local corticosteroid injection for the treatment of CTS provides significant improvement in symptoms for 3 months. On the other hand, no significant improvement was observed in electrophysiological parameters. Key Words: Carpal tunnel syndrome, Electrophysiology, Steroid injections Received 15 January 2013; received in revised form 15 April 2013; accepted 3 June 2013. Address for correspondence; Sang-Jun Na Department of Neurology, Konyang University Hospital, 158 Gwanjeodong-ro, Seo-gu, Daejeon 302-718, Korea Tel: +82-42-600-8814 Fax: +82-42-545-0050 E-mail: nukedoc@hanmail.net Copyright 2013 by The Korean Society of Clinical Neurophysiology 7

김지훈 이기욱 윤보라 김용덕 정언석 나상준 서론수근관증후군은가장흔한포착신경병으로정중신경이횡수근인대에의해포착되어통증이나감각이상, 근력약화와같은증상을나타내는질환이다. 1 유병률은연구마다차이가있으나약 3% 의인구에서발생하며, 남성보다여성에서흔하게발생한다. 2 수근관증후군은임상적으로손목원위부정중신경이분포하는영역의신경학적결손이있는경우진단할수있으며, 진단이확실치않은경우신경전도검사를통해확진할수있다. 3 수술적치료는가장근본적인치료방법으로써환자의 75-99% 에서효과적이며, 단 1% 미만에서만정중신경손상과같은심각한합병증을유발하는것으로알려져있다. 1,4 하지만실제로는환자의수술거부, 경제적인문제, 마취에따른위험성과같은이유로수술이어려운경우가있어비수술적치료를선택하게되는경우가많다. 비수술적치료로는경구용스테로이드제, 비스테로이드소염제, 이뇨제, 부목을이용한손목관절의운동제한, 치료적초음파등이사용되나장기적인효과에대한근거는부족하다. 1,5-8 국소스테로이드주사역시흔하게사용되는비수술적치료방법으로서여러연구에서치료후임상적호전을보고하고있으나대부분의연구에서재발률이높고, 장기적인효과에대해서는이견이있다. 9-18 특히국내환자의특성과연관해서국소스테로이드주사치료후임상적, 전기생리학적변화에대해서는거의알려진바가없다. 본연구에서는수근관증후군환자에서국소스테로이드주사치료후 3개월간의임상적, 전기생리학적소견의변화를관찰하고자하였다. 대상과방법 1. 대상 2011년 3월부터 2012년 2월까지건양대병원신경과외래를방문하여수근관증후군으로진단된환자중일부를대상으로전향적연구를시행하였다. 수근관증후군의진단은임상적으로정중신경이분포하는영역에국한된감각이상, 감각저하, 야간통증같은전형적인증상이있고, 신체검사에서 Tinel 징후또는 Phalen 징후를보이면서, 신경전도검사와근전도검사를시행하여원위부정중신경손상의증거가확실한경우로하였다. 당뇨병, 갑상선질환과같은전신질환이나손목의외상또는변형이있는경우, 신경전도검사와근전도검사에서다발말초신경병, 신경뿌리병증의증거가있는경우, 이전에수근관증후군에대하 여수술적치료나국소스테로이드주사치료를받은적이있는경우는대상에서제외하였다. 19 또한진행된수근관증후군으로심한근력저하나엄지두덩위축을보이는경우는대상에서제외하고수술적치료를권유하였다. 총 21명 (35손) 이연구대상에포함되었으며, 이들을대상으로국소스테로이드주사치료전, 치료후 1개월과 3개월에각각임상적평가와전기생리학적검사를시행하였다. 모든환자는치료와검사에대한설명을듣고연구에동의하였다. 2. 임상적평가임상척도의변화를평가하기위하여시각통증등급 (visual analog scale, VAS) 과 Boston 설문지 (Boston carpal tunnel questionnaire, BCTQ) 를사용하였다. 시각통증등급은환자의통증의정도를무증상인경우 0에서가장심한경우 10 까지표시하게하였다. Boston 설문지는수근관증후군에특화된자가작성설문지로우리말로번역하여사용하였다. 증상척도 (symptom severity scale, SSS) 11문항과기능척도 (functional status scale, FSS) 8문항으로나눠지는데각문항은무증상인경우 1점, 가장심한경우 5점이부여되며, 각문항을합산한후평균을구하여최종점수로하였다. 20 또한임상증상의변화를평가하기위하여감각이상의유무와잠에서깨어날정도의심한야간통증의유무를확인하였다. 3. 전기생리학적검사연구에포함된모든환자들은치료전정중신경과척골신경의운동-감각신경전도검사와상지와경추의근전도검사를통해수근관증후군으로진단되었으며, 치료후추적관찰시에는정중신경의신경전도검사만을시행하여치료전의정중신경운동신경원위잠복기 (distal motor latency, DML), 복합근육활동전위 (compound muscle action potential, CMAP), 감각신경원위잠복기 (sensory distal latency, SDL), 감각신경활동전위 (sensory nerve action potential, SNAP) 와비교하였다. 검사를실시할때의피부온도는섭씨 32도이상을유지하였으며, Cadwell 사의 Cascade 근전도기계를사용하였다. 정중감각신경전도검사는정방향방법을사용하였으며 2수지와 3수지사이의시작부위에서자극하여근위부 14 cm에부착한기록전극에서감각신경활동전위를측정하였다. 정중운동신경전도검사는엄지두덩근육중앙부에활동기준기록전극을부착한후근위부 5 cm에서자극하여복합근육활동전위을측정하였다. 8 Korean J Clin Neurophysiol / Volume 15 / June 2013

수근관증후군에서국소스테로이드주사후임상적, 전기생리학적변화 4. 국소스테로이드주사모든환자는동일의사에의해국소스테로이드주사가시행되었다. 주사방법은 25 gauge 주사바늘을손목주름근위부 1 cm에서긴손바닥근의척측에피부와 45도각도로삽입한뒤원위부를향해 1 cm 가량전진하여 1 ml의 40 mg triamcinolone과 1 ml의 1% lidocaine을혼합하여주사하였다. 시술중에환자가정중신경이분포하는영역에감각이상을호소하면주사바늘의위치를재조정하였다. 11,16,17 5. 통계분석국소스테로이드주사후전기생리학적변화와시각통증등급, Boston 설문지의증상척도, 기능척도의변화는 paired t-test를사용하였으며, 잠에서깨어날정도의야간통증과감각이상이나타났는지에대한여부는 chi-square test를통해평가하였다. 통계분석은 SPSS 17.0을이용하였으며 p값이 0.05 이하일때통계적으로의의가있다고판정하였다. 결과 1. 환자의일반적인특징연구에포함된 21명 (35손) 중여자는 19명, 남자는 2명이었으며, 오른손병변이 4명, 왼손병변이 3명, 양손병변이 14명에서관찰되었다. 연령은 34세에서 73세까지로평균연령은 48.6±11.6세였고, 증상이있었던기간은 3개월에서 72개월까지다양하였으며평균유병기간은 22.4±19.3개월이었다 (Table 1). 2. 임상적변화임상척도와임상증상의변화는 Table 2로정리하였다. 치료전과비교했을때, 치료후 1개월과 3개월의임상척 도와임상증상은각각모두통계적으로유의하게감소하였다 (p<0.005). 시각통증등급의평균은치료전 8.4±1.2에서치료후 1개월에 2.2±1.2로감소하였으며, Boston 설문지의증상척도, 기능척도도각각 2.9±0.7에서 1.7±1.0로, 2.1±0.5에서 1.5±0.7로감소하였다. 치료후 3개월에는시각통증등급 3.6±3.5, Boston 설문지의증상척도 2.0±1.3, 기능척도 1.7±0.8로치료후 1개월에비해증가하는추세를보였으나치료전과비교할때에는여전히통계적으로유의하게낮았다. 감각이상은치료전 35손 (100%) 에서나타났으나치료후 1개월, 3개월에는각각 14손 (40%), 24손 (69%) 에서만나타났으며, 잠에서깨어날정도의야간통증은치료전 30손 (86%) 에서나타났으나치료후 1개월, 3개월에는각각 6손 (17%), 10손 (29%) 에서만나타나두임상증상모두치료전과비교하여통계적으로유의하게감소하였다 (p<0.001). 하지만치료후 1개월과 3개월을비교했을때에는, 치료후 3개월에모든임상척도와임상증상들이조금씩악화되는양상을보였는데, 이중에서시각통증등급 (p=0.004), Boston 설문지의기능척도 (p=0.034), 감각이상 (p=0.015) 은치료후 Table 1. Demographic features of the patients Patients Number of patients 21 (35 hands) Age±years 48.6±11.6 Female/Male 19/2 Affected side Right 4 Left 3 Bilateral 14 Mean duration of symptoms±sd (month) 22.4±19.3 Values are presented as Mean±SD. Table 2. Clinical data at baseline, 1 and 3 months after treatment Parameter Baseline 1 month 3 months VAS 8.4±1.2 2.2±3.2 * 3.6±3.5 * SSS 2.9±0.7 1.7±1.0 * 2.0±1.3 * FSS 2.1±0.5 1.5±0.7 * 1.7±0.8 Paresthesia (%) 100 40 * 69 * Night awakening (%) 86 17 * 29 * Values are presented as Mean±SD. * The results of comparison against baseline (t-test) are statistically significant at p<0.001 level, The result of comparison against baseline (t-test) is statistically significant at p=0.002 level. VAS; visual analog scale, SSS; symptom severity scale, FSS; functional status scale. Korean J Clin Neurophysiol / Volume 15 / June, 2013 9

김지훈 이기욱 윤보라 김용덕 정언석 나상준 Table 3. Median nerve conduction study data at baseline, 1 and 3 months after treatment Parameter Baseline 1 month 3 months Mean±SD Mean±SD p-value Mean±SD p-value DML, ms 5.0±1.3 4.9±1.3 0.059 4.9±1.2 0.362 CMAP, μv 8.1±2.1 8.3±1.9 0.212 8.2±1.9 0.605 SDL, ms 3.9±0.8 3.7±0.8 0.084 3.8±0.7 0.327 SNAP, μv 20.2±4.4 22.2±8.7 0.089 21.1±6.1 0.215 All p-values are in comparison against baseline values. DML; distal motor latency, CMAP; compound muscle action potential, SDL; sensory distal latency, SNAP; sensory nerve action potential. 1개월과비교하여통계적으로도유의하게증가하였다. 3. 전기생리학적변화정중신경의신경전도검사소견의변화는 Table 3으로정리하였다. 운동신경원위잠복기의평균값은치료전 5.0± 1.3 ms에서치료후 1개월에 4.9±1.3 ms로치료전과비교하여감소하는경향을보였으나통계적유의성은없었으며 (p=0.059), 치료후 3개월에도치료전과비교하여통계적으로유의한변화는없었다 (p=0.362). 또한복합근육활동전위, 감각신경원위잠복기, 감각신경활동전위모두치료전과치료후 1개월, 3개월간에통계적으로유의한차이가없었다 (p>0.05). 고찰수근관증후군에서국소스테로이드주사는연구마다차이가있으나약 75% 이상에서증상호전을기대할수있으며, 9-18 무작위임상실험에서도속임약군에비해높은치료효과를보이는것으로알려져있다. 9,10 또한일부연구에서는임상증상의호전뿐만아니라전기생리학적검사결과의호전도보고하고있다. 10-13,17 하지만많은연구들에서 12개월내재발률이 8-100% 로다양하게나타나장기적인효과는불분명하다. 9-11,14-17 본연구에서도수근관증후군환자에서국소스테로이드주사치료후임상적호전을관찰할수있었다. 하지만치료후 1개월에는뚜렷한호전을보이다가 3개월에는 1개월에비해다시악화되는양상을보였는데, 이러한결과는수근관증후군에서국소스테로이드주사가 1개월이내의임상증상의개선에효과적이나장기적인효과는불확실하다는근거기반분석과맥락을같이한다. 21 국소스테로이드주사가단기적인효과에그치는원인으로는스테로이드가정중신경의허혈, 염증, 부종을일시적으로완화시킬수있으나, 22 수근관증후군의근본적인원인인횡수근인대의 압박을제거하지는못하며, 그외에반복적으로손을사용하는직업과같은외부적인요인을통제하기어려운점등을들수있다. 14 최근수근관증후군에서국소스테로이드주사의효과에대한일부연구에서는임상적또는전기생리학적기준으로중증도를구분하여경도또는중등도환자들만을대상으로하였을때장기적인효과가있을가능성을보고한경우도있다. 12,13,18,23 하지만각연구마다중증도를구분하는기준이다르고, 경도와중등도환자들만을대상으로하였음에도장기간효과를보이지못한경우도있어 15 아직근거가부족하다. 본연구에서도임상적으로심한근력저하나엄지두덩위축을보이는환자를제외하고연구를진행하였음에도전기생리학적검사소견의호전을관찰할수없었고, 치료후 3개월에는 1개월에비해임상적으로다시악화되는추세를보여장기적인효과를기대하기어려웠다. 하지만본연구에포함된환자들의유병기간이 3개월에서 72개월로다양하고, 치료전시각통증등급과 Boston 설문지점수가상대적으로높았던점이결과에영향을미쳤을가능성이있다. 수술적치료는수근관증후군의원인인횡수근인대의압박을제거할수있는가장근본적인치료방법으로이전의많은연구들에서효과가입증되었으며다양한종류의비수술적치료와비교해서도증상개선에보다우수한것으로알려져왔다. 24,25 하지만국소스테로이드주사와수술적치료를비교한세연구중, 22,26,27 두연구에서는수술적치료가국소스테로이드주사에비해증상개선과장기적인효과에서보다우수한것으로나타났으나, 22,27 다른한연구에서는치료 1년뒤국소스테로이드주사와수술적치료를받은군간에통계적으로유의한치료효과의차이를보이지않았으며오히려단기간의증상개선효과는국소스테로이드주사가우수한것으로나타나 26 어떠한치료가더효과적인지아직논란이있다. 25 일반적으로는보다중증의환자에게수술적치료가선호되나아직까지어 10 Korean J Clin Neurophysiol / Volume 15 / June 2013

수근관증후군에서국소스테로이드주사후임상적, 전기생리학적변화 떠한환자에게어떠한치료가이득이되는지에대한근거는부족하다. 22 최근의한생존연구에서는국소스테로이드주사치료를받은수근관증후군환자들중 1년, 5년내에수술적치료가필요했던환자는각각 15%, 33% 였으며당뇨병, 여성, 전기생리학적으로진단된환자에서수술적치료를필요로하는경우가많은것으로나타나이러한위험인자들을고려하여일차적치료방법을결정할것을제안하였다. 23 또한치료받지않은수근관증후군환자의자연적인경과를관찰한연구에서는 4분의 1 이상의환자가특별한치료없이도 10-15개월안에증상이호전된다고보고하였으며, 짧은유병기간과젊은나이가양성예후인자로나타났다. 28 이러한결과들은수근관증후군의일차적치료방법을결정함에있어수술적치료이전에비수술적치료를고려해야한다는근거가된다. 국소스테로이드주사방법은사용되는약제와주사바늘의삽입방법에따라다양하다. 이전연구들에서사용된스테로이드제제로는 methylprednisolone, 9,10,12-14 hydrocortisone, 16 triamcinolone, 11,16,17 bethamethasone 15 등이있으나각연구마다사용된스테로이드의종류와용량이다르며, 연구방법에도차이가있으므로어떠한약제가더효과적인지는아직알수없다. 한연구에서는속효성스테로이드인 hydrocortisone과지속성스테로이드인 triamcinolone의효과를비교하였으나유의한차이를보이지않았다. 16 약제에국소마취제의포함여부도연구마다차이를보이는데, 국소마취제를함께주사하는근거는통증을경감시킬수있으며주사후일시적으로정중신경분포영역의감각이저하되는것이약제가올바르게투여되었는지를가늠할수있기때문이다. 9 주사바늘을삽입하는위치는수근관인접한부위에주사하는고전적인방법이이전연구들에서많이사용되었으나, 10,16,27 최근에는보다근위부에주사하는방법이정중신경손상과같은심각한합병증발생이적다는주장도있다. 9 본연구에서는지속성스테로이드인 triamcinolone을국소마취제인 lidocaine과혼합하여고전적인방법으로주사하였다. 주사후모든손에서정중신경분포영역의일시적인감각저하를확인하였으며, 24시간이내로지속된정중신경분포영역의저린감을호소한 2손외에정중신경손상과같은심각한합병증은나타나지않았다. 따라서본연구에사용된방법은이전연구결과들과마찬가지로효과적이며안전한방법이라할수있겠다. 본연구의제한점으로는첫째, 상대적으로짧은추적기간으로인해국소스테로이드주사의장기적인효과를판단할수없었다. 비록치료후 3개월에도치료전과비교해서는치료효과가있었으나 1개월과비교해서는효과가 감소하는양상을보여장기적인효과를입증하기는어려웠다. 둘째로는대조군또는속임약군이없는점이다. 하지만이전의연구에서국소스테로이드주사는속임약에비해효과적인것으로밝혀져있으므로, 9,10 속임약을사용하는것은윤리적인문제가있다고판단하였다. 셋째로작은표본크기로인해오차가발생했을가능성이있으며, 하위그룹분석을시행하지못하여국소스테로이드주사에좋은반응을보일수있는예측인자를확인하지못한점이있다. 마지막으로우리말로번역하여사용한 Boston 설문지에대한유효성및반복측정신뢰도에대한연구가선행되지못하여연구의한계로작용할수있다. 저자들은수근관증후군에서국소스테로이드주사가단기적인증상개선에효과적이며안전한치료방법임을확인하였다. 따라서국소스테로이드주사는약물치료에반응하지않으면서수술적치료를결정하기어려운수근관증후군환자에서유용하게사용될수있겠다. REFERENCES 1. Dawson DM. Entrapment neuropathies of the upper extremities. N Engl J Med 1993;329:2013-2018. 2. Atroshi I, Gummesson C, Johnsson R, Ornstein E, Ranstam J, Rosen I. Prevalence of carpal tunnel syndrome in a general population. JAMA 1999;282:153-158. 3. Jablecki CK, Andary MT, Floeter MK, Miller RG, Quartly CA, Vennix MJ, et al. Practice parameter: Electrodiagnostic studies in carpal tunnel syndrome. Report of the American Association of Electrodiagnostic Medicine, American Academy of Neurology, and the American Academy of Physical Medicine and Rehabilitation. Neurology 2002;58:1589-1592. 4. Boeckstyns MEH, Sørensen AI. Does endoscopic carpal tunnel release have a higher rate of complications than carpal tunnel release. An analysis of published series. J Hand Surg 1999;24: 9-15. 5. Gerritsen AA, de Vet HC, Scholten RJ, Bertelsmann FW, de Krom MC, Bouter LM. Splinting versus surgery in the treatment of carpal tunnel syndrome. A randomized controlled trial. JAMA 2002;288:1245-1251. 6. Chang MH, Chiang HT, Lee SS, Ger LP, Lo YK. Oral drug of choice in carpal tunnel syndrome. Neurology 1998;51:390-393. 7. Chang MH, Ger LP, Hsieh PF, Huang SY. A randomised clinical trial of oral steroids in the treatment of carpal tunnel syndrome: a long term follow up. J Neurol Neurosurg Psychiatry 2002;73:710-714. 8. Ebenbichler GR, Resch KL, Nicolakis P, Wiesinger GF, Uhl F, Ghanem AH, et al. Ultrasound treatment for treating the carpal tunnel syndrome: randomised sham controlled trial. BMJ 1998;316:731-735. 9. Dammers JW, Veering MM, Vermeulen M. Injection with Korean J Clin Neurophysiol / Volume 15 / June, 2013 11

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