ISSN 1225-1682 (Print) ISSN 2287-9293 (Online) 대한골절학회지제 29 권, 제 3 호, 2016 년 7 월 J Korean Fract Soc 2016;29(3):213-220 http://dx.doi.org/10.12671/jkfs.2016.29.3.213 Review Article 거골골절 방태정 김순규 정형진 인제대학교의과대학상계백병원정형외과학교실 Fracture of the Talus Tae Jung Bang, M.D., Sun-Kyu Kim, M.D., Hyung-Jin Chung, M.D. Department of Orthopedic Surgery, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, Korea Although talus fractures are uncommon, proper management is important because they are often associated with severe complications. Talar neck and body fractures occupy most of the talar fractures. It remains controversial whether talar neck fractures require emergent or elective treatment. Elective definitive fixation, however, may reduce risks of wound complications. Many surgeons recommend dual surgical approaches anteromedial and anterolateral to allow accurate visualization and anatomic reduction. Although there are various methods of fixation, the use of plates is necessary in comminuted talar fractures. Outcomes may vary and will be dependent on the degree of the initial fracture displacement. It is necessary to restore articular congruency and axial alignment for normalizing hindfoot function. Common complications include posttraumatic arthritis, avascular necrosis, malunion, and nonunion. Key Words: Talus, Neck, Body, Fracture, Complications 서 거골골절은모든골절에서약 1%, 전체족부골절의약 3%-6% 정도로드문골절이다. 1) 거골은경골, 비골, 종골및주상골과관절을이루고있기때문에넒은연골표면을가지고있고, 근육이나건과의연결없이주위구조물과는단지관절연골및활액막으로연결되어있는특징으로인해손상시외상성관절염의발생가능성이높다, 또한거골체부로의혈액순환이원위부를통해공급이되 론 Address reprint requests to: Hyung-Jin Chung, M.D. Department of Orthopedic Surgery, Inje University Sanggye Paik Hospital, 1342 Dongil-ro, Nowon-gu, Seoul 01757, Korea Tel: 82-2-950-1399ㆍFax: 82-2-950-1398 E-mail: orthoman@paik.ac.kr Financial support: None. Conflict of interest: None. 는특징으로인해거골경부의손상시무혈성괴사등의심각한합병증이동반되므로중요하게취급되어왔다. 2) 거골경부는단면적이좁고얇은약한피질골로이루어져있어전체거골골절의약 45% 를차지하는골절이며, 3) 가장흔한기전은하퇴부에대해발이과도하게족배굴곡되는것이다. 교통사고나추락사고가가장흔한원인으로, 족관절의족배굴곡이일어나면거골하관절후방부의관절막과인대들이파열되고거골의경부가원위경골의전방에충돌하면서골절이시작된다. 족배굴곡력이더가해지면종골과거골두를포함한족부가전방으로전위되면서종골의탈구가일어나게되고거골체부는후내측으로전위되어족관절내과의후방과아킬레스건사이에끼이게된다. 4) 거골경부골절에대한분류는 1970년 Hawkins 5) 에의해발표되었고, 1990년 Canale 6) 이제4형을추가한분류법이치료지침과예후예측에도움이되어현재가장많 Copyright c 2016 The Korean Fracture Society. All rights reserved. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 213
214 Tae Jung Bang, et al. 이사용되고있다 (Table 1, Fig. 1). 거골체부골절은모든거골수상의 7%-38% 를차지하며, 7) 추락사고가가장흔한원인이며, 거골이경골천장과종골사이에서축성압박력에의해발생한다. 경부와체부골절을나누는기준은거골외측결절 (lateral tubercle) 후방에골절선이있으면체부골절로간주한다. 8) 체부골절에서약 50% 까지거골경부골절이동반된다는보고가있으며그치료에있어경부와체부는같은원칙을공유하게되는경우가많다. 9) Sneppen 등 10) 은거골체부골절을해부학적위치에따라분류하였다. 골연골골절 (type A, transchondral or osteochondral), 관상면전단골절 (type B, coronal shear), 시상면전단골절 (type C, sagittal shear), 후방결절골절 (type D, posterior tubercle fracture), 외측돌기골절 (type E, lateral process fracture), 압궤골절 (type F, crush fracture) 로나뉜다. Fortin과 Balazsy 11) 는이를좀더간단히하여분열골절 (type I, proper or cleavage fracture, horizontal or shear or coronal), 돌기골절 (type II, talar process or tubercle fracture), 압궤골절 (type III, compression or impaction fracture) 로나누었다 (Fig. 2). 거골경부나체부의골절은교통사고나추락등과같은고에너지손상에의한경우가많고 3) 전위가있을경우약 20% 에서개방성골절이보고되고있으며, 개방성손상이아니더라도튀어나온골절편에의해피부의허혈이발생하는경우가있다. 이러한경우에는골절을조기에정복하여피부의괴사및감염을예방해야한다. 본종설에서는거골골절중가장많은발생빈도를보이며치료및합병증등의측면에서중요한경부골절과체부골절의진단및치료등에대한연구를요약하고, 최신수술적치료방법들에대해알아보도록한다. Table 1. Hawkins Classification of Talar Neck Fractures 6) Type I: nondisplaced fracture without subluxation; risk of avascular necrosis 0% to 13% Type II: displaced vertical talar neck fracture with subtalar joint; risk of avascular necrosis 20% to 50% Type III: displaced vertical talar neck fracture with subluxation of the subtalar and tibiotalar joint; risk of avascular necrosis 75% to 100% Type IV: displaced vertical talar neck fracture with subluxation of the subtalar, ankle, and talonavicular joint; risk of avascular necrosis 100% Fig. 1. Hawkins classification of talar neck fractures. 6) Fig. 2. Classification of talar body fractures. 11)
Fracture of the Talus 215 1. 보존적치료 치료 제1형골절은전산화단층촬영에서전위가없는골절로석고고정으로치료할수도있다. 2 mm 이상의전위가있을경우거골하관절의접지압력 (contact pressure) 이변하기때문에외상성관절염이올수있다. 따라서주기적으로방사선추시를하면서추가적인전위가없음을확인하여야한다. 7) 대개 6-8주간의단하지석고고정하에서체중부하를하지않도록하며, 이후 6주가량은보조기 (boot brace) 를착용한상태로제한적인체중부하를허용할수있다. 2. 수술적치료 전위가있는제 2, 3, 4 형의골절은정확한정복이필요하며, 전위로인하여혈액순환장애및연부조직의손상이발생할수있다. 관혈적정복전에도수정복을시도해볼수있으나만족스러운정복이이루어지지않았다면수술실에서최대한빠른정복을시행해야한다. 초기에정복을얻었다고하더라도대부분의전위가있는거골골절의경우추후관혈적정복술의시행이필요하기때문에골절및동반된탈구의정복후에는관혈적정복술및내고정술이표준치료로인정받고있다. 1) 수술시기수술시기는골절주변의연부조직상태에따라결정된다. 초기에수술을시행했을때합병증으로는창상이개, 피부괴사및감염이수술이후 77% 정도에서나타난다. 5,9) 이전에는거골경부및체부골절에서수상초기에정복및고정을통해서골괴사가능성을낮출수있다는주장이많았으나최근에는고정시기와골괴사발생가능성사이에연관성이없다는보고들이발표되고있다. 12-14) 이는골절이후에도거골체부의후방혈관에의해혈액공급이어느정도유지되기때문으로생각된다. 이러한이유로최근에는금속내고정의적절한시기를필론골절과같이연부조직상태가안정화되는수상 1-3주가지난이후로보는경향이있다. 이러한지연수술이후초기합병증이 2%-10% 까지감소하였다는보고도발표되고있다. 12,13,15) Xue 등 16) 은분쇄골절과탈구가동반된고에너지손상의경우일차적으로탈구및골절의정복과핀고정및외고정술후연부조직이안정화된이후에관혈적도달법을통한내고정을추천하기도한다. 2) 도달법전경골건과후경골건사이를통과하는전내측도달법 17) 을사용하면골절부위가잘노출되고, 내과 (medial malleolus) 절골술이필요할경우쉽게연장이가능한장점이있다. 주상골의조면 (tuberosity) 에서족관절내과까지의절개선을통해골절부에접근하게되며이때족근관동맥과삼각분지혈관 (deltoid branch) 손상가능성이있기때문에주의하여야한다. 전외측도달법을사용할경우골절부위의노출을얻으면서내측부의혈액순환에추가적인손상을줄일수있다고하였다. 장무지신전건의외측부에서제 4 중족골을연결하는절개선을통해신근지대 (extensor retinaculum) 를절개하고신경혈관구조와단무지신전건을외측으로젖힌후거골경부를노출시키게되며, 이때족근동동맥 (artery of sinus tarsi) 의손상을주의하여야한다. 18) Mullen 등 18) 의사체연구에따르면전방접근법이거골 - 주상골간관절부터족관절까지충분한시야를확보할수있어가장넓은시야를확보할수있다는보고를하였으나이는혈관의손상가능성이높은단점이있다. 특히분쇄골절이동반된경우에는내측혹은외측의정확한정복을위해서전내측도달법및전외측도달법을사용하는이중도달법이거골경부및체부전방골절에서추천되고있다. 이중도달법이거골괴사와연관성이있다는보고는없지만거골경부하방의절개시족근관동맥과삼각분지혈관의보호가필요하며삼각인대의손상도주의해야한다. 거골체부골절에서필요시에는내과절골술 (Fig. 3) 을같이시행할경우에충분한시야를확보할수있다. 18) 3) 내고정방법위의다양한도달법을이용하여일단골절이정복되면골유합이되기까지전단력을충분히견딜수있는내고정이필요하다. 거골경부골절에서내고정방법으로나사가가장흔하게사용되는데, 전내측또는전외측도달법을이용한전방에서후방을향하는나사가흔히사용되고있다. Swanson 등 19) 은후방에서전방을향하는나사가더나은고정력을보인다고보고하였고, 전방나사와후방나사를동시에고정하는시도도이루어지고있다. 20) 나사는두개의나사를평행하게삽입하는것이바람직하나경부의분쇄가있는경우에는나사고정시의압박으로인해부정유합이발생할수있으므로평행하지않게삽입하는것이좋다. 이때나사의방향을정확히잡기위해서는유관나사의사용이이점을가질수있으며나사머리가관절면에돌출되지않도록카운터싱크 (counter sink) 를하거나무두나사 (headless screw) 를이용하는것이도움이된다. 나사
216 Tae Jung Bang, et al. Fig. 3. (A, B) Preopertive radiographs show a comminuted talar neck and body fracture (A: anteroposterior view; B: lateral view). (C, D) Postoperative radiographs show a fixation using multiple screws and lateral plate with dual (anteromedial & anterolateral) surgical exposures and medial malleolar osteotomy (C: anteroposterior view; D: lateral view). 의재질은티타늄재질의나사가술후자기공명영상 (magnetic resonance imaging) 촬영시간섭을줄일수있어서무혈성괴사의예측및평가시에도움이될수있다. 거골의골절치료에있어서염두에두어야할것중하나는거골의재혈관화를위해서는견고한고정이필수적이라는것이다. 이는거골이해부학적으로역행성혈액공급을받기때문에골절이후적절한혈액공급을받지못하게되는경우가많기때문이다. 이런의미에서분쇄골절에서나사만을이용하는고정은견고한고정을위해부족할수있기때문에작은골절편까지고정할수있는작은금속판의사용이필요하다 (Fig. 4). 21) Fleuriau Chateau 등 22) 은내측혹은외측의지지금속판을이용하여해부학적정복을얻고내반부정유합을방지할수있었다는보고를하였다. 나사만을이용하는고정은분쇄골절의압박을막아주는역할을할수있지만금속판을이용한고정은내부의평행한여러개의나사를동반하기때문에골절부위의견 고한고정에더유리하다. 금속판의두께는얇은것을선택하는것이좋겠으나견고한고정을이루는것도중요하기때문에적절한두께의선택이필요하다. 금속판의고정위치는골절의상태에따라거골회전축의상방또는하방에위치함으로써부정유합을방지할수있다. 또한분쇄골절에서는장축을가로지르는압박나사의사용시경부의과도한압박및내측족부의단축등을일으킬수있어비압박나사의사용이추천된다. 22) 거골경부의내측및배부에분쇄골절이있는경우내고정이후내반및신전된상태로해부학적정렬에실패하는경우가많다. 전외측도달법을이용하여거골경부의외측을직접노출시킨이후외측에대한정확한해부학적정복을하면이러한위험성을줄일수있다. 골절의분쇄부위에대해서는국소적골이식또는동종골이식을통해기질과역학적지지를제공하는것이추천된다. 해부학적정렬을유지하고부정유합을방지하려면작은골절편까지정확한내고정을해야한다.
Fracture of the Talus 217 Fig. 4. (A, B) Preopertive radiographs show a comminuted talar neck fracture with subtalar joint subluxation (A: anteroposterior view; B: lateral view). (C, D) Postoperative radiographs show fixation using one anteroposterior screw, one posteroanterior screw, and one lateral plate with screws (C: anteroposterior view; D: lateral view). 1. 부정유합 합병증 불유합은 5% 이하로비교적드물지만, 23) 부정유합은불유합의빈도보다높아 0%-37% 정도로보고되고있으며이는단순방사선촬영상축성부정정렬을관찰하기힘들기때문에실제보다낮게측정된것으로생각된다. 12,13,15,16) 부정유합은불유합의빈도보다높아약 30% 정도이며, 내측분쇄골절로인한내반변형이가장흔하다. 2 mm 이상의전위는거골하관절의생역학을변화시킨다는결과가있으며, 24) Canale과 Kelly 25) 는 5 mm 이하의전위와 5도이하의각변형을허용범위로정하기도하였다. 내반변형은후족부를내반, 전족부를회외전시킨상태에서보행을하게되어통증이발생하고결국거골하관절의퇴행성변화가가속된다. 또한족배부정유합 (dorsal malunion) 은전방충돌증후군을발생할수있다. 2. 무혈성괴사 경부골절후무혈성괴사발생률은 1형에서는드물지만, 2형에서약 25%, 3형에서는약 50%, 4형에서는 75% 이상에서발생하는흔한합병증이고, 초기골절전위정도와연관성이높으며개방성골절일경우빈도는더증가하게된다. 괴사된부위에골침착및석회화, 주위의상대적인골다공증등으로방사선상골밀도가증가되어무혈성괴사에서는경화소견으로나타난다. 26) 무혈성괴사가일어나지않는경우에는수상후 6-8주경에거골원개 (dome) 의연골하골에서재혈관화에의한골흡수가일어나방사선투과성선이관찰되는데이를 Hawkins 징후라고한다. 이는수상초기에체부의생존가능성을알아볼수있는중요한소견이며, 감수성 (sensitivity) 은높으나특이성 (specificity) 이높은징후는아니다. 자기공명영상검사는무혈성괴사정도를검사하는데유용하다 (Fig. 5). 하지만수상 3 주이전에는위음성이많기때문에수상후 3주가지나야검사를시행하고, 27) 이를통해무혈성괴사의유무, 범위까지알수있게되어체부의함몰가능성을결정할수있다.
218 Tae Jung Bang, et al. Fig. 5. (A) Postoperative radiograph shows a subcondral sclerosis ten weeks after screw fixation of comminuted talar neck fracture. Hawkins sign is absent. (B, C) These T2-weighted magnetic resonance imaging scans were obtained ten weeks after a talar neck fracture and demonstrate focal osteonecrosis of talar body (B: coronal section; C: sagittal section). 무혈성괴사의치료는논쟁의여지가있다. 일반적으로초기수상시에는정확한정복및견고한고정이치료원칙으로되어있다. 수상 6-8주에 Hawkins 징후가보이지않아무혈성괴사가예측되더라도골절이유합될때까지는체중부하를금지시키고고정을하게된다. 재혈관화후골이재생될때까지 36개월까지도걸릴수있는기간동안체중부하를금지하는것은사실상불가능하다. 통증이있으며괴사의증거가있는환자에서거골원개에가해지는힘을어느정도감소시키고, 내반및외반이되지않도록하는슬개건부하보조기를사용할수있다. 환자에게이러한치료에도불구하고함몰이일어날수있고, 함몰은선택된체중부하의치료방법보다무혈성괴사의자연경과와관련이있음을주지시켜야한다. 이러한보존적치료를하여도증상이지속될경우수술적치료를고려해볼수있다. 거골체부의괴사범위가넓고, 족관절에퇴행성관절염이발생하면체부를절제하고경골의전면피질골을활주 (sliding) 시켜거골경부에삽입하는 Blair 유합술이나경종골간유합술이이용되고있다. 11) Blair 유합술은거골을완전히절제하는것에비해정상적인발모양이유지되고하지단축의문제가없고거골하관절의운동이어느정도보존된다는장점이있다. 3. 외상성관절염 외상성관절염역시거골골절에서 47%-90% 까지나타나는흔한합병증이다. 28) 거골체부골절의경우최종추시에서대부분의환자에서관절염이관찰된다. 최신의수술기법을시행했음에도불구하고절반이상의환자에서거골 하관절염을보이게된다. 결 거골골절은드물게발생하지만합병증과기능적인후유증이남을수있는골절이다. 이중거골의체부와경부골절은최초수상시혈관을포함한주변연부조직, 연골, 골절의상태에따라적절한수술시기, 수술방법등을선택하는것이예후에큰영향을미칠수있으므로조심스러운접근이필요하다. 전위성거골경부및체부의골절에대해서는수상이후최대한빠른도수정복이필요하며, 관혈적정복술및내고정술의시행시기에대해서는조기에시행하는원칙으로되어있지만, 연부조직이충분히안정된후시행하는방법도추천되고있다. 수술시에는접근법과나사의개수, 방향, 적절한금속판의사용등을통해관절면과축성정렬의회복을기대할수있다. 이는발목관절및후족부의기능의회복에기대할수있게한다. 적절한수술이후에도무혈성괴사및외상성관절염의발생가능성에대한예측및그에대한처치에신경을써야한다. 론 References 1) Abdelgaid SM, Ezzat FF: Percutaneous reduction and screw fixation of fracture neck talus. Foot Ankle Surg, 18: 219-228, 2012. 2) Peterson L, Goldie IF: The arterial supply of the talus. A study on the relationship to experimental talar fractures.
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ISSN 1225-1682 (Print) ISSN 2287-9293 (Online) 대한골절학회지제 29 권, 제 3 호, 2016 년 7 월 J Korean Fract Soc 2016;29(3):213-220 http://dx.doi.org/10.12671/jkfs.2016.29.3.213 Review Article 거골골절 방태정 김순규 정형진 인제대학교의과대학상계백병원정형외과학교실 거골골절은드물지만종종심각한합병증을유발할수있기때문에적절한처치가중요한골절이다. 거골골절에서는경부및체부의골절이대부분을차지하고있다. 거골경부골절에대해응급수술을시행할것인가정규수술을시행할것인가에있어서는논란의여지가있다. 하지만연부조직의안정화이후정규수술을시행했을때상처합병증의발생가능성을줄일수있다. 충분한시야확보와해부학적정복을얻기위해가장추천되는도달법은전내방과전외방의두개의절개를사용하는이중도달법이다. 고정방법은여러가지방법이존재하며분쇄경부골절의경우에는금속판의사용이필수적이라고할수있겠다. 예후는골절당시의전위정도와연관이있으며, 정상적인후족부의기능의회복을위해서는관절면의회복과축의정렬이필수적이다. 합병증으로는외상성관절염, 무혈성괴사, 부정유합, 불유합등이알려져있다. 색인단어 : 거골, 경부, 체부, 골절, 합병증 교신저자정형진서울시노원구동일로 1342, 인제대학교상계백병원정형외과 Tel 02-950-1399, Fax 02-950-1398, E-mail orthoman@paik.ac.kr Copyright c 2016 The Korean Fracture Society. All rights reserved. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 220