Korean J Pain Vol. 22, No. 2, 2009 대한통증학회지 2009; 22: 171-175 DOI:10.3344/kjp.2009.22.2.171 증례 경추부신경근병증으로오인된신경통성근위축증 증례보고 분당서울대학교병원마취통증의학과, * 서울대학교의과대학마취통증의학교실박찬도ㆍ김준우 * ㆍ최종범ㆍ이민정 * ㆍ문지연ㆍ이평복 Neuralgic Amyotrophy Considered as Cervical Radiculopathy A case report Chan Do Park, M.D., Joon Woo Kim, M.D.*, Jong Beom Choi, M.D., Min Jung Lee, M.D.*, Jee Youn Moon, M.D., and Pyung Bok Lee, M.D. Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, *Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea Neuralgic amyotrophy is a syndrome with a broad range of clinical manifestations. It is characterized by acute, severe pain in the shoulder or arm lasting several days or weeks, followed by muscle weakness and atrophy as the pain diminishes. The diagnosis is based on typical clinical features, electromyography (EMG) and a nerve conduction study. The early and correct diagnosis is important to preclude unnecessary testing or surgical procedures. A 59-year-old female patient presented with pain and weakness involving her right palm and 1 3rd fingers. Three weeks before presentation, she noted the sudden onset of severe right shoulder and forearm pain. After the pain was reduced, she noted persistent right palm and 1 3rd finger pain and weakness. On cervical MRI, there was a mild central disc protrusion at C4 5 and C5 6. Electrodiagnostic testing was performed and she was diagnosed with neuralgic amyotrophy. One week after hospital treatment, her pain was relieved from VAS 10 to 3 and she was discharged with mild weakness of the thumb and index finger during pinch grips. (Korean J Pain 2009; 22: 171-175) Key Words: cervical radiculopathy, neuralgic amyotrophy. 신경통성근위축증은 Parsonage-Turner syndrome으로도알려져있으며, 어깨및상지부위에갑작스럽게극심한통증이발생한후수일에서수주후통증이가라앉으면서근위약과근위축을보이는드문질환이다. 급성기에는대개근위약이나근위축은없이통증만을호소하게되며통증또한비전형적으로나타날수있으므로어깨및상지통증을나타내는여러가지질환에대해감별진단을요하며, 임상에서흔히접할수있는질환이 아닌만큼초기진단이어려울수도있다. 또한감별진단단계에서이질환을고려하지않을경우수술과같은부적절한치료나기타불필요한검사가이뤄질수도있는만큼임상적경험에근거한정확한진단이중요하다. 10 만명중 2 3명정도발생한다고알려져있는이질환을가진환자를만나게되어본증례를문헌고찰과함께보고하는바이다. 접수일 :2009 년 6 월 10 일, 1 차수정일 :2009 년 7 월 13 일승인일 :2009 년 7 월 18 일책임저자 : 이평복, (463-707) 경기도성남시분당구구미로 166 분당서울대학교병원마취통증의학과 Tel: 031-787-7499, Fax: 031-787-4063 E-mail: painfree@snubh.org Received June 10, 2009, Revised July 13, 2009 Accepted July 18, 2009 Correspondence to: Pyung Bok Lee Department of Anesthesiology and Pain, Seoul National University Bundang Hospital, 166, Gumi-ro, Bundang-gu, Seongnam 463-707, Korea Tel: +82-31-787-7499, Fax: +82-31-787-4063 E-mail: painfree@snubh.org
172 CD Park, et al / Korean J Pain Vol. 22, No. 2, 2009 증례평소건강했던 59세여자환자로우측손바닥과 1 3 번째손가락의통증및위약감을주소로본원통증치료실을방문하였다. 환자는방문 3주전등산을다녀온후갑작스럽게우측어깨및전완부가떨어져나가는듯한극심한통증이발생하여인근병원에서주사및경구진통제처치후 3일가량지나어깨부위의극심한통증은줄어들었으나, 이후우측손바닥및 1 3번째손가락에통증과위약감이발생되어지속되었다고한다. 통증은콕콕쑤시면서전기가통하는느낌, 저린느낌과같은양상을띠었으며시각통증등급 (visual analogue scale, VAS) 10 정도로수면장애를동반하고있었다. 근력검사상우측 1 3번째손가락의굴곡이 Grade 4-정도로약해진상태였고이로인해엄지와검지의집게동작이제한되어젓가락사용및펜글씨쓰기가제한되었다. 그외 Spurling s test, 심부건반사등의다른이학적검사상특이소견은없었다. 특이한것은등산을다녀온후 3번째손가락의끝부분에 2개의작은수포성병변이발생한것인데그동안병변의확산이나변화는없는상태였다. 그외에우측엄지두덩의현저한위축양상을보였다 (Fig. 1). 손바닥과손가락부위의통증및저린감에대해 6번, 7번경추신경근병증이아닐까일차적으로의심하였고통증이심한상태였으므로입원후검사를진행하였다. 입원후시행한혈액검사는정상소견이었고, 체열촬영 Fig. 1. Photograph of both hands. (A) Small vesicles on the right third finger tip. (B) Thenar atrophy and incomplete grip of right hand. Fig. 2. Thermographic scan shows the image of upper extremity. Right hand is more hyperthermic than the left one.
박찬도외 5 인 : 신경통성근위축증 173 결과우측손의온도가좌측에비해최고 1.94 o C 가량증가한소견을보였다 (Fig. 2). 경추부 MRI 상에서는경추 4 5번, 5 6번사이의경미한추간판탈출증이외에는특이소견은없었다. 이에대상포진에의한근위약이나신경근병증, 말초신경병증등에대한감별진단을위해근전도및신경전도검사를시행한결과수근관증후군이나경추부신경근병증은없었고주관절상방의정중신경병증및중등도의축삭신경절단소견을보여병력과이학적검사등을종합적으로고려할때신경통성근위축증으로진단되었다. 통증을조절하고통증으로인한비활동성근위축이나관절구축등의합병증을방지하기위해경추경막외차단및성상신경절차단, 물리치료, 재활운동치료등을반복적으로시행하였다. 1주가량의입원치료후시각통증등급은 10에서 3 4 정도로감소하였으며손가락의위약감은 4+ 정도로약간의호전만보인상태로퇴원하였다. 퇴원 4개월후인발병 5개월후환자는 1 2번째손가락감각의약간무딘느낌과 3번째손가락끝의경미한한랭이질통을호소하였고, 엄지두덩의위축은회복된양상이었으나엄지및검지굴근의위약감으로인한젓가락사용과펜글씨쓰기의불편함은여전히남아있는상태였다. 고찰신경통성근위축증은주로상완신경총을침범하며아직까지정확한원인이밝혀지지않은드문질환으로, 1887년 Dreschfeld에의해처음보고된이후, Parsonage- Turner syndrome, brachial plexus neuropathy, idiopathic brachial plexopathy, multiple neuritis of the shoulder girdle, shoulder girdle syndrome 등다양한이름으로명명되어왔다. 1) 초기임상양상은다양하게나타날수있으며다른신경학적또는비신경학적질환과유사한증상을나타내기도하므로환자는여러과의의사를거치게되고잘못된진단을받는경우도생기게된다. 비록전반적으로예후는좋은것으로되어있어서만족스러운회복을보이게되지만, 지속적인통증이나근위약같은후유증을남기기도한다. 2) 그러므로초기에적절한진단을함으로써불필요한검사나수술등을방지하고통증조절및물리치료를포함한적절한치료가이뤄지도록해야할것이다. 신경통성근위축증의발생률은연간 10만명당 2 3 명정도이며, 3,4) 주로 20 60대에호발하며 3개월부터 81세에이르기까지폭넓은연령대에서발생하는것으로보고되고있다. 5,6) 남녀성비는 2:1 11.5:1 정도로남성에서좀더많이발생하는것으로알려져있다. 6) 원인에따라특발성과유전성두가지로구분되는데특발성의경우정확히밝혀지진않았으나감염, 예방접종, 힘든운동, 수술, 임신및출산과같은선행요인으로인해자가면역기전과같은면역관련반응이작용하는것이아닌가추정되고있으며, 1) 유전성의경우염색체 17q25의 SEPT9 gene의변이에의해상염색체우성형태로나타난다고한다. 7) 본환자의경우는증상이발생하기전에등산을다녀온것이외에는특별한원인이될만한선행요인은없었으며등산또한평소보다힘들지는않았다고해서딱히의심할만한원인은없는상태였다. 전형적인신경통성근위축증은어깨부위에갑작스럽게극심한통증이발생하여수일에서수주간지속되다가이후통증이가라앉으면서근위약, 근위축및감각저하가나타나게되며, 대개편측성으로나타나지만 30% 에서는양측성으로나타날수도있다. 1) 초기통증은흔히어깨와목, 그리고드물게견갑골이나후흉벽부위에서도발생하며팔이나전흉부로방사통을유발하기도한다. 8) 통증이가라앉으면서발생하는근위약은주로상완신경총상부영역에서나타나며긴가슴신경침범에의한익상견갑이종종보고되고있으며, 1,9) 주로근위약을나타내는근육은극상근, 극하근, 앞톱니근, 이두근, 삼두근, 삼각근등이다. 1,10) 그외에감각저하나이상감각을나타내기도하고발한, 부종, 이영양성변화, 온도차이와같은자율신경계이상현상을보이기도한다. 8) 본환자의경우는어깨부위에통증이나타난후어깨부위근육기능은보존된상태에서손바닥과손가락의위약감및통증을호소하였는데이는전형적인신경통성근위축증과는임상양상이다른원위부변이형에해당하는형태라하겠다. 진단은대개임상적으로이뤄지게되며근전도및신경전도검사를통해상완신경총의말초신경병증을확인한다면확진에도움이되는것으로되어있는데, 최근발표된문헌에의하면감각신경전도검사상 20% 미만에서만양성소견을보이는걸로나타나전기생리학적검사의진단적가치는그다지높지않은것으로보고되었다. 11) 워낙특징적인임상경과를나타내는질환이므로대개병력만으로도진단이가능하며, 이를위해서는어깨와팔부위에유사한증상을나타내는다른질환들에대한정확한감별진단이선행되어야하겠다 (Table 1). 6) 진단및감별진단시고려해야할기본적인세가지사항
174 CD Park, et al / Korean J Pain Vol. 22, No. 2, 2009 Table 1. Differential Diagnosis of Upper Extremity Pain and/or Paresis Neurological disorders Cervical radiculopathy, degenerative Cervical radiculopathy, disk rupture Mononeuritis multiplex/pns vasculitis Multifocal motor neuropathy Brachial amyotrophic diplegia Non-neurological disorders Shoulder or elbow joint pathology Cervical spondylosis Complex regional pain syndrome Difference with neuralgic amyotrophy Insidious onset, slowly progressive or fluctuating course Acute onset, symptoms in same dermatome Symptoms also in legs or distal arm, subacute, progressive Painless, no sensory symptoms, distal predominance, progressive Insidious onset, no sensory symptoms painless, progressive Difference with neuralgic amyotrophy Exacerbated by joint movement, relief at rest, passive restriction of ROM Posture dependent, no focal deficit, fluctuating course Diffuse pain and weakness subacute onset with progression 은우선통증이급성이고극심한지 (VAS > 7) 여부를확인하고만약그렇지않은경우에는다른질환을우선고려해야하겠으며, 둘째로어깨관절의수동적운동범위의제한이있는가를확인하여만약제한이있다면점액낭염이나석회성힘줄염같은어깨관절자체의문제를우선고려해야한다. 마지막으로통증, 마비, 감각장애등의모든증상이동일한신경분포를따른다면신경통성근위축증보다는경추부신경근병증을우선고려해야하겠다. 혈액검사나단순방사선촬영은대개정상으로나타나며 MRI상신경의병변이 T2W 영상에서신호증강을나타낼수있으나이는아급성이나만성기로접어들어야나타나는소견으로초기진단에있어서는민감도가떨어지며, 최근에는 magnetic resonance neurography라는검사를통해급성기진단에도움을줄수있다는보고가있지만아직논란중에있다. 2) 결국신경통성근위축증은아직까지명확한진단기준이나검사방법이확립되지않은질환으로자세한문진과이학적검사를바탕으로주로임상적으로감별진단을시행하고, 근전도검사를보조적으로사용하여상완신경총영역에서말초신경병증을나타내는 fibrillation potential 과 positive wave를확인한다면확진에도움이될수있겠다. 11,12) 본환자의경우손바닥과손가락부위의통증및저린감에대해 6번, 7번경추신경근병증이아닐까일차적으로의심하였었고, 손가락끝에수포성병변이있어서대상포진에의한통증및근위약의가능성도생각했었다. 13) 그러나경추부 MRI상증상과연관된병변은확인할수없었고, 수포성병변의경우도 3주동안변화가없다는점과신경분포양상과도맞지않다는점에서대상포진의가능성도배제하였으며결국근전도검사를시행한후상완신경총의일부인정중신경의신경병증및중등도의축삭신경절단소견을보여병력과이학적검사등을종합적으로고려할때신경통성근위축증으로진단 하게되었다. 치료는대개보존적치료를하게되는데 NSAIDs와아편유사제의병합요법및신경차단술을통한통증조절, 그리고물리치료및재활운동치료를통한관절과근육의구축을방지하는데초점을맞춰야하겠으며, corticosteroid의경우마비증세의회복을촉진시킨다는점에서는도움이되나재발을더증가시킨다는단점이보고되고있다. 1) 적절한진단과치료가이뤄지는경우 80 90% 에서 2 3년이내에회복이될정도로예후는양호한것으로그동안알려져왔으나, 8) 최근자료에의하면 6년이내에 50% 미만에서만완전한회복이이뤄진다는보고도있었으며, 14) 2006년 van Alfen과 van Engelen은 1) 246 case를 3년이상경과관찰한결과 2/3 이상에서지속적인통증과마비증세가있었고 6년이상관찰한경우약 1/3에서만성통증이지속되었다고하여예후가그다지양호하지않다는보고가나오고있는실정이다. 결론적으로어깨부위에갑작스럽게극심한통증이발생하는경우감별진단시신경통성근위축증을염두에둠으로써불필요한검사나수술과같은처치를방지할수있으며, 조기에적절한통증조절및물리치료, 재활운동치료등을시행함으로써관절이나근육의구축을방지하여환자의기능적회복및일상생활로의복귀를앞당길수있을것이다. 참고문헌 1. van Alfen N, van Engelen BG: The clinical spectrum of neuralgic amyotrophy in 246 cases. Brain 2006; 129: 438-50. 2. Duman I, Guvenc I, Kalyon TA: Neuralgic amyotrophy, diagnosed with magnetic resonance neurography in acute stage: a case report and review of the literature. Neurologist 2007; 13: 219-21. 3. Beghi E, Kurland LT, Mulder DW, Nicolosi A: Brachial
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