REVIEW 대한족부족관절학회지제 17 권제 1 호 2013 J Korean Foot Ankle Soc. Vol. 17. No. 1. pp.17-22, 2013 소족지변형의치료 인제대학교의과대학상계백병원정형외과학교실 Treatment of Lesser Toe Deformities Su-Young Bae, M.D., Ph.D. Department of Orthopedic Surgery, Inje University, Sanggye Paik Hospital, Seoul, Korea =Abstract= Lesser toe deformities such as mallet toe, hammer toe and claw toe are annoying problems not only to patients but also to orthopaedic surgeons because they are not easy to manage or treat. Though they occupy very small portion in whole body, they are notorious for unpredictable surgical results. It can make clinical results better to understand these deformities more comprehensively and to make strategic surgical plan for each target deformity. Key Words: Less toe deformity, Mallet toe, Hammer toe, Claw toe, Curly toe 서 론 무지를제외한작은족지의질환중추족지 (mallet toe), 망치족지 (hammer toe), 갈퀴족지 (claw toe), 만곡지 ( 굴지증, curly toe) 등의변형은환자에게나이를치료하는정형외과의사에게나골칫거리이다. 보행과신발착용의곤란과통증을유발하므로비록신체말단의아주작은부위이긴하나간과하기어려운불편을야기한다. 이를치료하는정형외과의사는수술적치료와보존적방법사이에서, 수술을하더라도그시기와방법사이에서갈등하게된다. 수술을시행하는 Received: January 20, 2013 Revised: February 7, 2013 Accepted: February 14, 2013 Corresponding Author: Su-Young Bae, M.D., Ph.D. Department of Orthopedic Surgery, Inje University Sanggye Paik Hospital, 761-1, Sanggye 7 dong, Nowon-gu, Seoul 139-707, Korea Tel: +82-2-950-1399 Fax: +82-2-950-1397 E-mail: youngos@paik.ac.kr 경우에도수술후에지속적으로통증과불편을호소하거나변형이재발되거나혹은인접부위에새로운통증이나변형이발생할수있어치료경과가비교적일정하지않기때문이다. 따라서이들작은족지의변형과질환들은보다포괄적으로이해하고각각의변형에대해전략적치료계획을수립하는것이중요하다. 용어및해부학적이해 1. 용어의이해 우리말로는 mallet toe를추족지, hammer toe를망치족지라고한다. Mallet은대개좀더가볍고작은나무망치나북채등을뜻하며 hammer는머리가무겁고커서못을박거나돌을깨는데쓰는쇠망치를뜻할뿐두망치모양에큰차이는없다. 우리말용어에서도 추 자는망치를뜻하기때문에굳이해석하자면둘다 - 17 -
망치형태로구부러진족지의변형을말하는것이나의학적관습용어인관계로족지의원위지간관절의굴곡변형을추족지 (mallet toe, 작은망치모양변형 ), 근위지간관절의굴곡변형을망치족지 (hammer toe, 큰망치모양변형 ) 라고이해하는것이좋겠다. 갈퀴족지 (claw toe) 는고양이과동물의발톱을세운앞발혹은새의발과발톱의모양을뜻한다. 갈퀴족지의형태는추족지혹은망치족지보다는복잡한복합변형으로중족지간관절의신전과근위지간관절의굴곡변형을함께일어난다. 만곡지혹는굴지증 (curly toe) 은발가락이측면으로휘어져있는모양을지칭하는것으로골의변형또는연부조직의변형이혼재되어나타나고위의변형들이대개후천적변형인데비해측만족지의대부분은선천성변형이다. 1) 2. 해부학적이해족지의안정성은관절의관절막, 관절의인대와족장판, 족저근막등연부조직과골성조직으로구성되는정적구조에의한안정성과근육및건에의해유지되는동적안정성에의해유지된다. 동적인안정은보행과신발에의해수시로변화하는관절의위치와모양에도불구하고관절을제위치에유지시켜야하기때문에정적구조에비해더중요하고복잡하다. 동적안정성은장족지신전근및장족지굴곡근과단족지신전과굴곡근, 골간근과충양근및소족지외전근으로이루어지는족부내재근에의해유지된다. 장족지신전건의 기능은발목관절의신전과굴곡에의해서도영향을받으며내재근에의해중족족지관절이중립또는굴곡위에있어야만족지를신전시킬수있는반면장족지굴곡건은중족족지관절의위치와상관없이항상원위족지를강하게굴곡시킨다. 단족지신전건은장족지신전건의외측으로주행하여부착하고단족지굴건은장족지굴건심부를통과하여중위지골에부착하여근위지간관절을굴곡시킨다. 내재근은네개의충양근과골간근으로이루어진다. 충양근은중족족지관절의족장판 (plantar plate) 과신전지대 (extensor hood) 의내측에부착하는데관절의중심보다족저부에위치하기때문에관절을굴곡시키는역할을한다. 골간근은횡중족인대의상부를지나중족족지관절의중심축보다족저로위치하여역시이관절의굴곡근으로작용한다. 하지만관절이신전위치가되면중심축보다족배로이동하여오히려관절을신전시키는역할을하게되는데이특성은갈퀴족지의병인에매우중요하다 (Fig. 1). 2) 추족지 (Mallet Toe) 추족지는작은족지의원위지간관절의굴곡변형을뜻하며원위지골이족저굴곡되어발가락의끝이 Figure 1. Normal balance between intrinsic and extrinsic muscle in lesser toe can be disrupted by dorsal malposition of intrinsic axis in abnormal extension contracture of metatarsophalangeal joint. Figure 2. Flexion contracture of distal interphalangeal joint in mallet toe(top), proximal interphalangeal joint in hammer toe(middle), and combined deformity of hyperextension of metatarsophalangeal joint and flexion contracture of interphalangeal joints in claw toe(bottom). - 18 -
소족지변형의치료 바닥과닿게되고지단및굴곡되어돌출된원위지간관절배부에통증과과각화증또는궤양을일으키는변형이다. 3) 작은신발의착용에의해긴발가락이굴곡되어시작되고변형이고착되는경우도있고외상에의해장족지신전건의부착부가이완되어발생하기도한다. 당뇨환자에게서흔하고원위지간관절뿐아니라근위지간관절도어느정도굴곡될수있다 (Fig. 2). 2. 치료신발이원인이된경우에는넉넉한신발을신게하고족지의패드등을이용하여자극을완화시키는치료를한다. 이미원위지간관절의변형이고착되어수동적교정이불가능해지면보존적수단으로는부족한경우가많다. 수술은굴곡변형을일으키는장족지굴근은절단하거나원위중족지간관절의절제관절성형술또는관절고정술을시행하는데때로는궤양이나감염을동반하고단기회복이요구되는고령의환자에게서는족지원위부를절단하는수술을하기도한다. 4) 굴곡건절단술은원위지간관절의족저부에세로또는가로의작은절개를가하고장족지굴건을절단한후도수조작하여굴곡변형된관절을교정하는수술이며부분마취만으로간단히시행할수있다. 때로는변형이오래되어족배부연부조직이두꺼워지고과각화된피부로인해굴곡건절단만으로교정이불충분할때가있는데이때는족배에서피부절개를가하고과각화된피부와늘어난관절막, 아탈구된근위지골의원위관절면을절제하거나원위지골의근위관절면을함께제거한후굴곡된원위부를곧게펴봉합하고 K-강선으로고정하는절제관절성형술을요한다. 술후 K-강선은약 3주내지4주정도유지했다가제거하며이때원위지간관절은유합될수도있고가관절로남을수도있지만임상결과에미치는영향은큰차이없는양호하다. 한다. 3) 변형이심하고오래되면이차적변형으로서중족지간관절은신전되고원위지간관절은근위지간관절과중족지간관절의굴곡또는신전정도에따라굴곡되기도하고신전되기도한다. 따라서망치족지변형이심해지면갈퀴족지변형과구분하기어렵다. 망치족지는대개모든발가락에발생하지않고긴발가락인 2, 3 족지에발생하는경우가많고원위지간관절의굴곡변형과중족지간관절의신전변형이항상존재하지는않는것으로구분된다. 가장흔한원인은끝이좁고굽이높은신발의장기착용이다. 그러나추족지와마찬가지로외상이나염증성질환등에의해근위지간관절의족배부신전건복합체가늘어지거나손상된경우에도발생하고무지외반증에의해공간이협소해지면이차적변형으로제 2 족지의중첩이일어나근위지간관절이굴곡되어발생하기도한다. 5) 2. 치료보존적치료는추족지와마찬가지로변형이유연한경우에는전족부 (toe box) 가넓고높은신발의착용, 중족골패드나족지패드등을사용하거나중족골두를들어올리기위한깔창을이용하기도하며근위지골의족배전위를막는테이핑을시행하기도한다. 변형이유연한지는환자를앉히고변형이발생한족지의중족골두를밀어올려근위지간관절의굴곡변형이교정되는지를보아판단한다 (push-up test). 보존적치료로해결이되지않는강직성변형혹은심한변형에서는다양한수술방법을조합하여시행할수있다. 망치족지에서와마찬가지로변형의중심이 망치족지 (Hammer Toe) 망치족지는추족지와달리근위지간관절의굴곡변형 (Fig. 2) 을지칭하는데제 2, 3 족지에많이발생 Figure 3. Girdlestone-Taylor operation: splitted long flexor tendon transfer into dorsal extensor hood. - 19 -
되는근위지간관절의절제관절성형술, 장족지신전건의연장술, 장족지굴곡건의이전술, 중족족지관절의연부조직유리술, 중족골의길이가긴경우중족골의길이를줄이거나중족골두를들어올리는수술을고려해볼수도있다. 6,7) 이런수술방법들은갈퀴족지변형에서도마찬가지로적용될수있다. 8) Girdlestone-Taylor 수술이라고도불리는굴곡건의배부이전술은가장흔히이용되어온수술방법이다 (Fig. 3). 9) 장족지굴곡건을근위지골의배부에이전하여중족지간관절을굴곡시키는역할을하게하여근위지간관절의굴곡변형을회복시킨다. 근위지간관절의변형이이미강직성이라면근위지간관절의절제관절성형술이나관절유합술을함께시행해야효과를얻을수있다. 망치족지에서절제관절성형술을시행하던관절유합술을시행하던대체로 90% 이상에서만족할만한결과를얻을수있으며유합술후유합율은 80% 정도로알려져있다. 10) 따라서유합을목적으로수술을시행하고완전유합을얻지못했다고해도결과에큰차이는없으며골절제가과도한경우는족지관절이불안정해질수있으므로골절제는한번에크게하지않는것이좋다. 수술후회전변형, 경도의각변형등은비교적흔한합병증으로 K-강선을제거한후테이핑등을통해경도의부정정렬은극복할수있다. 보다더흔한문제는족지의부종과비후인데족지관절절제성형술을시행한경우에는시간이흐르면부종은대개호전된다. 하지만굴곡건이전술은영구적인족지비후를남길수있을뿐아니라족지의양측면으로건을통과시켜야하기때문에신경증상을남기거나때로는족지의괴사를유발하기도한다. 따라서이수술을시행할때는족지의혈류상태를점검한후시행하는것이매우중요하다. 건이전술의임상결과는 50% 에서 90% 까지다양하고비교적일관성없게보고되어왔기때문에 9) 사용하는빈도는줄고있는추세이다. 의주된변형은근위지간관절이아니라 중족지간관절의과신전변형 이다. 원인은주로신경인성질환이나근육의변성, 염증성질환이나외상, 요족등내재근기능의장애이다. 외재근에비해내재근의상대적인근력약화가나타나면족지의신전과굴곡의균형이깨지며내재근이중족지간관절을중립또는굴곡위로유지할만큼충분히강하지못하기때문에중족지간관절은신전된다. 상대적으로강한외재근, 즉족지신건은지속적으로신전지대 (extensor hood) 를근위로잡아당기기때문에중족지간관절은점점과신전되고내재근인골간근은관절의중심축에비해족배로전위되어오히려관절을신전시키는역할을하게된다. 반면족지굴건은상대적으로강하기때문에근위및원위지간관절을굴곡시켜갈퀴혹은새의발톱과같은형태의족지변형이고착화된다 (Fig. 1, 2). 족지에나타나는증상은굴곡구축된근위지간관절이나원위지간관절의족배부의과각화와통증이며과신전된중족족지관절족저의족장판 (plantar plate) 은원위로이탈하여족저의통증과때론궤양이발생하기도한다. 대표적인말초신경병변인당뇨병성말초신경병증에서는원위로부터운동신경의기능이점차소실되어내재근의마비가먼저일어나기때문에갈퀴족지변형이흔히동반되는데이때대부분감각저하를동반하기때문에돌출부에궤양혹은감염등의심각한합병증이비교적쉽게생길수있다. 2. 치료이학적검사를통해유연성변형인경우에는망치족 갈퀴족지 (Claw Toe) 앞에서언급한것처럼망치족지의심한변형은갈퀴족지변형과구분하기어렵다. 그러나갈퀴족지변형 Figure 4. Metatarsal head can be migrated proximally by classical Weil osteotomy (left). Modified Weil osteotomy with wafer resection (right) can make slight elevation of head and proximal migration at a same time. - 20 -
소족지변형의치료 지에서와같이보존적치료를시도할수있지만고정된변형이생기거나족지의지속적통증, 궤양등이발생할위험이있으면수술적교정을하는것이바람직하다. 수술적치료역시망치족지에서시행하는굴곡건이전술이나근위지간관절의절제관절성형술등을시행할수있으나발을디딘상태에서중족지간관절이과신전되지않도록중립위로유지하는것이치료의목표가되기때문에중족지간관절의배측관절막혹은인대유리술, 단족지신전건의절제술, 또는장족지신전건의연장술을흔히같이시행한다. 심한변형의수술적치료를위하여는족지신전건과굴곡건의연장과같은원리로중족골을단축시키거나중족골두의절제관절성형술을시행하기도한다. 11) 변형 Weil 절골술과같이중족골두를족배부로전위시면서길이를단축시키면비교적효과적으로족배로전위되었던중족지간관절의회전축을회복시킬수있다 (Fig. 4). 12) 또한갈퀴족지변형이장기간지속되면족장판의마모또는마멸이일어나족장판의균열이발생하기도하는데이런경우위의수술들뿐아니라족장판의봉합을시행하면중족지간관절을안정적으로유지시킬수있다. 13-16) 만곡지 ( 굴지증, Curly Toe) 만곡지는병명이라기보다는발가락이휘어있는모습을지칭한말로측만족지, 굴곡지, 내반족지, 중첩족지등으로혼용되어불리기도한다. 17) 하나또는둘이상의족지가족저굴곡되고외회전되며인접족지의아래로휘어들어가지단의압박에의한통증또는불편을 호소하게된다. 대개선천성이며양측으로발생하고가족력을갖는경우가많고성장하면서저절로호전되는경우는별로없다. 18) 병인은골성구조의이상에의해족지골이비대칭으로성장하는경우도있고소족지의내재근, 특히소족지외전근의형성부전에의하거나연부조직의구축에의한경우도있다. 2. 치료소아의경우에는굴곡건의유리술이나심한경우인접족지와의합지를만드는수술을하기도하고굴곡건을신전지대로이전하는수술을하기도하지만심하지않은경우에만효과가있다. 17-20) 이미성인이된후나타나는증상혹은골조직의모양이상에의한경우에는중간지골을절제하고배외측피부가짧아지도록재봉합하거나중간지골에배외측의설상골편을절제하고약간내회전시켜고정하는쐐기회전절골술을시행하기도한다 (Fig. 5). 결론 작은족지의다양한변형과질환들은변형의정도및변형의유연성, 이차적주변조직의변형이나인접관절의변형등다양한요소들에의해치료방침이나예후등이결정된다. 뿐만아니라환자의요구나활동도, 나이와동반질환등여러요소들을고려하여치료방법을결정해야하기때문에각각의환자에게적합한치료방법을선택적으로적용하는것이중요하며반드시수술에앞서동반된만성질환이나허혈성질환을감별해야심각한합병증을막을수있다. REFERENCES Figure 5. Lateral closing wedge and rotational osteotomy of 4th middle phalanx to correct curly toe deformity in adult. 01. SM Cha, JS Suh. Treatment of congenital toe anomalies. J of Korean Foot Ankle Society. 2012;16:148-55. 02. Shirzad K, Kiesau CD, DeOrio JK, Parekh SG. Lesser toe deformities. J Am Acad Orthop Surg. 2011;19:505-4. 03. Schrier JC, Louwerens JW, Verheyen CC. Opinions on lesser toe deformities among Dutch orthopaedic departments. Foot Ankle Int. 2007;28:1265-70. - 21 -
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