대한관절경학회지제13 권제2호 2009 Journal of Korean Arthroscopy Soc. Volume 13, Number 2, June, 2009 종 설 이중다발전방십자인대재건술 가천의과학대학교길병원정형외과학교실 이범구 심재앙 서 전방십자인대파열의치료로주로단일다발전방십자인대재건술 (single bundle anterior cruciate ligament reconstruction) 이시행되어왔다. 하지만최근여러역동적인조사를통해생역학적으로기존의단일다발전방십자인대재건술후회전불안정성이있음이보고되었고 6,12,14,19,20,22-24,32,34), 이러한회전불안정성으로인해운동복귀도안되고, 지속적인퇴행성관절염도유발됨이알려졌다 21,35). 이를개선하기위해이중다발전방십자인대재건술 (double bundle anterior cruciate ligament reconstruction) 이많이개발되어보고되었으나, 이중다발전방십자인대재건술도정확히해부학적위치에시행하지않으면안정성, 특히회전안정성을얻을수없으므로정확한위치로의이중다발전방십자인대재건술이필요하다 39). 저자는전방십자인대의해부학적위치를논하고, 이중다발전방십자인대재건술의우월성을생역학적, 임상적, 생물학적으로기술하고, 이중다발전방십자인대재건술시터널형성을위한도달법에관하여논하고, 정확한이중다발전방십자인대재건술을위한저자의경험을약술하고자한다. 본 1. 전방십자인대의해부학 Address reprint request to Beom Koo Lee, M.D. Department of Orthopaedic Surgery, Gil Medical Center, Gachon University 1198 Kuwol-dong, Namdong-gu, Incheon, Korea Tel: 82-32-460-3384, Fax: 82-32-468-5437 E-mail: bklee@gilhospital.com 론 론 전방십자인대의전내측다발은길이 37.7 mm, 폭 8.5 mm이며, 후외측다발은길이 20.7 mm, 폭 7.7 mm로알려져있다 33). 전방십자인대의부착부위는해부학적기준, 방사선상기준, 관절경상기준으로알수있다. 해부학적으로대퇴부착부위는전내측다발이대퇴골의외측이분융기선 (lateral bifurcate ridge) 뒤에위치하고, 후외측다발은외측이분융기선의앞에위치한다 8). Yasuda 등 36) 은대퇴부착부위의전내측다발이대퇴후방보다 5 mm 원위부에, 후외측다발은슬관절 90도굴곡상태에서대퇴골과경골이만나는점에서수직으로선을그어연골끝부분부터 5 내지 8 mm 앞쪽에위치하고, 경골부착부위는후외측다발이후방십자인대로부터 5 mm 앞경골극 (tibial eminences) 사이에있고, 전내측다발은그보다 7 mm 전방에위치한다고보고하였다. Zantop 등 41) 은경골부착부위에서전내측다발의중심이외측반월상연골전각부위로부터 5.2 mm 내측, 2.7 mm 후방에있고, 후외측다발은 4.1 mm 내측, 11.2 mm 후방에위치한다고보고하였다. 대퇴부착부위의중요한표지자 (landmark) 로이용되는외측과간융기선 (lateral intercondylar ridge) 이방사선시상면 (sagittal plane) 상으로는 Blumensaat 선의 79% 점에서 75.5도내리는위치에있다 7). 따라서이선뒤에서와부 (fossa) 를이분하면전내측다발과후외측다발의중심점을알수있다. 관상면 (coronal plane) 상으로는시계개념으로전내측다발은 10시 40분에서 11시방향, 후외측다발은 3 시 10분방향에위치한다고하나, 이는슬관절굴곡각도에따라위치가달라질수있으며해부학적위치와같은판정을하려면 prone kneeling view를찍어야하나, 수술시촬영이불가능하므로관상면보다는시상면방사선사진에의존하여판단하는것이더좋을것으로사료된다 38). 경골부착부위는방사선시상면상으로 Colombet 등 5) 은 Amis와 Jakob 선 2) 의 36% 에서 52% 에해당된다고하였고, Zantop 등 41) 은 Stäubli와 Rauschning 측정방법 31) 에서 30% 에서 44% 에해당된다고하였다. 관절경상으로도부착부위를알수있다. 관절경으로부착부위를정확히알려면대퇴의후방까지정확히보고판정하여야하는데, 전외측구멍 (portal) 을통해관찰시대퇴후방까지잘보이지않아오류를많이낼수있으므로전내측구멍을통해대퇴외과의후방까지정확히관찰하는것이매우중요하다. 각다발의잔유물 (remnant) 이있으면잔유물의중심을기준으로하면되나, 많은경우잔유물이남아있지않다. 이경우전내측다발의부착부위는대퇴골의외측이분융기선뒤에위치하고있고, 후외측다발의부착 105
대한관절경학회지제 13 권제 2 호 2009 년 부위는외측이분융기선앞에위치한다는점을착안하여이분융기선을확인후각각의다발중심을정할수있다. 또한두다발의중심점은슬관절 102도굴곡시평형해진다는점을이용하면더욱더확실히알수있다 27). 2. 이중다발전방십자인대재건술의우월성 1) 생역학적관점전방십자인대는태아 (fetus) 에서전내측다발과후외측다발이뚜렷히구분되며 9), 각각의다발이슬관절의굴곡각에따라받는긴장도가달라전내측다발은굴곡에서, 후외측다발은신전시최대부하를받으므로그기능이다르다고할수있다 26). Sonoda 등 30) 자기공명영상추시에서 pivit shift 검사양성군에서후외측다발의신호증가가있다고하였고, Zantop 등 40) 은사체실험에서후외측다발을절제하고회전력부하시불안정성이증가함을보고하여, 후외측다발이회전안정성에기여하고있음이알려졌다. Belisle 등 3) 은사체에서전방십자인대에긴장을알수있는differential variable reluctance transducers (DVRTs) 를부착시킨실험에서단일다발전방십자인대재건술시전내측다발의긴장형 (strain pattern) 만보이고후외측다발의기능은거의없고, 이중다발전방십자인대재건술시는원래의전방십자인대의긴장형에가깝게긴장됨을보고하였다. Georgoulis 등 12) 도 6개의사진기를이용한 optoelectronic system을이용한검사로단일다발전방십자인대재건술시경골의내회전이더일어남을보고하였고, Dual-orthogonal fluoroscopic system을이용한 Papannagari 등 24), radiostereophotogrammetric analysis (RSA) system 을이용한 Tashman 등 34) 도슬관절굴곡 30도이상에서단일다발전방십자인대재건술시외회전이더됨을보고하였다. Lie 등 19) 도 electromagnetic (EM) navigation을이용한실험에서단일다발전방십자인대재건술시긴장을많이주어도 pivot shift가없어지지않음을보고하였고, 그외많은저자들이 navigation을이용한실험에서단일다발전방십자인대재건술시회전불안정성이있음을보고하였고, 이중다발전방십자인대재건술은거의정상에가까운회전안정성이있음을보고하였다 6,14,20,22,23,32). Morimoto 등 22) 은단일다발전방십자인대재건술시전외측및후내측관절면에압력이증가하고이중다발전방십자인대재건술시거의정상에가깝게압력분포가일어남을보고하여이중다발전방십자인대재건술이관절염측면에서도유리함을보고하였다. 2) 생물학적관점 Kondo와 Yasuda 17) 는이중다발전방십자인대재건술후이차적관절경상긴장도와활액막형성을기준으로할때전내측다발의 3.8%, 후외측다발의 3% 만이불량인우수한결과를보고하였다. 저자도자기공명영상추시에서의이식건신호강도및긴장도, 이차적관절경상긴장도, 활액막형성면에서좋은결과를경험하였다 (Fig. 1). 3) 임상적관점임상적으로슬관절에회전불안정이있는경우증상과기능에영향을주며 4,11,15), 지속적인회전불안정은내측관절면에전단 (shear) 을일으켜관절염을유발할수있다 21,35). 여러저자들에의해이중다발전방십자인대재건술시전방및회전안정성이우월함이보고되었으나임상적평가는단일다발전방십자인대재건술과이중다발전방십자인대재건술이통계상의미있는차이를보이지않는다고보고하였다 1,16,18,37). A B Fig. 1. The arthroscopic finding showed well-synovialized and apparent tensioned ACL graft (A). Follow-up MRI finding revealed well-visualized different bundles and low-intensity signals (B). 106
이중다발전방십자인대재건술 이범구외 3. 수술술기 1) 대퇴터널형성을위한접근법대퇴터널형성을위한접근법으로는경경골술식 (transtibial technique), 전내측구멍 (anteromedial portal) 을통한술식, Outside-in 술식이있다. 이중많이이용되고있는경경골술식의경우 Fu 등 10) 은대퇴터널을정확한자리에위치시키기가매우어려워전내측경경골술식을이용하는경우단지 3% 만이해부학적위치에전내측터널을위치할수있다하였고, 전내측구멍을통한술식은 99% 에서해부학적위치로전내측터널을만들수있다하였다 10,25). 그러나전내측구멍을통한술식도대퇴터널을정확한자리로위치시키기어렵고, 굴곡을적게하여시행시외측에서비골신경손상을일으킬수있다 13). 저자의경험으로는전내측구멍에관절경을위치시켜대퇴터널의위치를보며 Outside-in 술식으로대퇴터널을형성하면비록대퇴부에추가절개의단점은있으나비교적쉽고, 위험성없이정확한해부학적위치에대퇴터널을만들수있었다. 2) 저자의경험 (1) 적응증저자는활동이왕성한환자에서전방십자인대손상시가능하면이중다발전방십자인대재건술을하려고하였다. 그러나성장판이남아있는소아나, 외측인대재건술을동시에요하는경우, 근위경골절골술과같이시행시에는터널의수를줄이고자단일다발전방십자인대재건술을시행하였다. (2) 수술술기진단적관절경을시행하여전방십자인대파열을확인후슬건을채취하여, 전내측이식건으로반건양건을, 후외측이식건으로박건을이용하였다. 전내측다발은반건양건을 3-4 겹으로, 후외측다발은박건을 4겹으로만든후, 5-0 Ethibond 봉합사를이용하여말단매듭 (terminal tie) 과견인매듭 (tension tie) 의이중매듭 (double tie) 을만들었다. 직경은전내측다발이대부분 8 mm였고, 후외측다발이대부분 7 mm였으며, 길이는전내측다발이대부분 8 cm에서 10 cm였고후외측다발이 5 cm에서 7 cm였다. 대퇴, 경골터널내삽입되는이식건의길이는골유착 (osteointegration) 을위해 2 cm를목표로하였으며, 최소 1 cm 이상삽입되도록하였다. 매듭을만든슬건은전긴장 (pretensioning) 을준후재건술을시행하기전까지긴장을유지하였다. 남아있는전방십자인대를제거후과간절흔의협착이있는경우에만절흔성형술 (notchplasty) 을시행하였으며대부분의경우는절흔성형술이필요하지않았다. Outside-in 술식을위해외상과 (lateral epicondyle) 의근위부로약 2 내지 3 cm를절개하고외측광근 (vastus lateralis) 및관절낭을상방으로견인하여유도핀 (guide pin) 이삽입될공간을확보하였다 (Fig. 2). 유도핀삽입시전내측다발은슬관절을 70도굴곡상태에서, 후외측다발은 90도굴곡상태에서관절경을전내측구멍에위치시키고 70도유도관 (guide) 을중앙구멍 (central portal) 에위치시킨후각각의다발의잔유물 (remnant) 의중앙점을목표로 Outside-in 술식을이용하여유도핀을삽입하였다. 두다발의유도핀의위치는여러가지기준을복합하여결정하였다. 전내측다발의유도핀은전내측다발잔유물의중앙이거나, 잔유물이없을때는외측과간융기선후방의와부중에서외측이분융기선의후방에있는와부의중앙, 절흔의후방경계에서약 6 mm 전방, 10시나 2시방향에위치하였고, 후외측다발의유도핀은후외측다발잔유물의중앙, 외측이분융기선의전방에있는와부의중앙, 90도굴곡상태에서경골과맞닿는수직선상에서관절연골의가장자리에서약 5 내지 8 mm 상방, 9시나 3시방향에위치하였다 (Fig. 3). 또한전내측구멍에서관절경으로관찰시 90도굴곡상태에서두유도핀이관절면에대해거의평행하도록하였다. 이는만성손상의경우잔유물이없거나절흔협착이있어절흔성형술을시행하는경우전내측다발과후외측다발의위치를결정하는데주로이용하였다. 경골터널은 40도유도관을이용하여전내측다발의유도핀은잔유물의전내측에, 후외측다발의유도핀은후외측에위치하도록하였다. 후외측다발의유도핀은경골극사이의후방, 후방십자인대의 5 mm 전방에위치하도록하였으며, 전내측다발의유도핀은후외측유도핀보다 8 mm 전방, 경골내극의앞쪽연장선의내측에위치하도록하였다 (Fig. 3). 경골의터널의입구는전내측다발의경우경골결절의내측에, 후외측다발의경우내측측부인대바로앞에위치하였다. 유도핀삽입후영상증강기 (image intensifier) 를이용하여위치를확인하였다 (Fig. 4). 유도핀의적절한위치여부확인후이식건의굵기에맞는크기의확공기로 Outside-in 술식으로확공 (reaming) 하여터널형성후펀치 (punch) 를이용하여 Ligament Plate 가삽입될공간을만들었다 28). 비꼰얇은 Fig. 2. We retracted the vastus lateralis muscle and the synovium (arrow) upward for the place of femoral guide pins. 107
대한관절경학회지제 13 권제 2 호 2009 년 철사를대퇴터널과경골터널을먼저통과시킨후철사에이식건을매달아통과시켰다. 이때이식건의대퇴부굵기가경골부보다굵은경우대퇴터널에서경골터널방향으로통과시키고, 경골부굵기가대퇴부보다굵은경우경골터널에서대퇴터널방향으로통과시켜이식건과터널간의부조화 (mismatching) 을줄이고자노력하였다. 대퇴부에서전내측다발은이식건을직접 Ligament Plate 에현수고정하였 고, 후외측다발은 2개의 Mersilene tape (Ethicon Inc, Somerville, USA) 을이용하여 Ligament Plate 에걸어고정하였다. Ligament Plate 는감입 (impaction) 후나사고정을시행하였다. 경골부의고정은 6.5 mm 해면골나사 (cancellous screw) 와와셔 (washer) 를이용하여견인매듭을미리묶은후나사에걸어원위부방향으로고정하여긴장을준후말단매듭을시행하여이중고정을하였다. 고정시 A B C D Fig. 3. We inserted the femoral anteromedial (A) and posterolateral (B) guide pins to the center of remnants with outside-in technique. The tibial guide pin of posterolateral bundle was placed the area between tibial eminences (C) and that of anteromedial bundle the point approximately 8 mm anteromedial to the tibial guide pin of posterolateral bundle (arrow) (D). A B Fig. 4. Both femoral anteromedial and posteorlateral guide pins were positioned anterior and posterior to the lateral bifurcate ridge (arrow) respectively (A). And then we checked out the position of guide pins by image intensifier (B). 108
이중다발전방십자인대재건술 이범구외 슬관절은약 15도굴곡상태를유지하였다. (3) 결과본저자는 2005년 10월부터 2007년 8월까지이중다발전방십자인대재건술을시행한 103예중동반손상이없었던 50예의결과를보고한바있다 29). 이중다발전방십자인대재건술의최소 1년이상추시에서임상적결과는 Lysholm 점수가평균 92.4±6.8점, IKDC 점수가 A 등급 35예 (70.0%), B 등급 14예 (28%), C 등급 1예 (2%) 로호전되었다. 불안정성검사에서 Lachman 검사는음성 40예 (80%), 경도양성 9예 (18%), 중등도양성 1예 (2%) 의결과를보였고, pivot shift 검사는음성 45예 (90%), 경도양성 5예 (10%) 의결과를보였으며, KT 2000 관절계검사는건측에비해 1.3± 1.6 mm의차이를보여임상적으로도우수할뿐아니라안정성에서도우수한결과를경험하였다. 다만이중다발전방십자인대재건술에서가장중요한 pivot shift 검사를객관적정량화할수없었던것은한계점으로사료되었다. 결 Outside-in 술식을이용한이중다발전방십자인대재건술은해부학적으로터널을만들기쉽고, 회전안정성이뛰어나높은스포츠복귀율, 적은퇴행성관절염이기대되나장기추시가요할것으로사료된다. 론 REFERENCES 01) Aglietti P, Giron F, Cuomo P, Losco M and Mondanelli N: Single-and double-incision double-bundle ACL reconstruction. Clin Orthop Relat Res, 2007;454: 108-113. 02) Amis AA and Jakob RP: Anterior cruciate ligament graft positioning, tensioning and twisting. Knee Surg Sports Traumatol Arthrosc, 1998;6 Suppl:2-12. 03) Belisle AL, Bicos J, Geaney L, et al.: Strain pattern comparison of double- and single-bundle anterior cruciate ligament reconstruction techniques with the native anterior cruciate ligament. Arthroscopy, 2007;23: 1210-1217. 04) Cohen M, Amaro JT, Ejnisman B, et al.: Anterior cruciate ligament reconstruction after 10 to 15 years: association between meniscectomy and osteoarthrosis. Arthroscopy, 2007;23: 629-634. 05) Colombet P, Robinson J, Christel P, et al.: Morphology of anterior cruciate ligament attachments for anatomic reconstruction: a cadaveric dissection and radiographic study. Arthroscopy, 2006;22: 984-992. 06) Colombet P, Robinson J, Christel P, Franceschi JP and Djian P: Using navigation to measure rotation kinematics during ACL reconstruction. Clin Orthop Relat Res, 2007;454: 59-65. 07) Farrow LD, Gillespie RJ, Victoroff BN and Cooperman DR: Radiographic location of the lateral intercondylar ridge: its relationship to Blumensaat s line. Am J Sports Med, 2008;36: 2002-2006. 08) Ferretti M, Ekdahl M, Shen W and Fu FH: Osseous landmarks of the femoral attachment of the anterior cruciate ligament: an anatomic study. Arthroscopy, 2007;23: 1218-1225. 09) Ferretti M, Levicoff EA, Macpherson TA, Moreland MS, Cohen M and Fu FH: The fetal anterior cruciate ligament: an anatomic and histologic study. Arthroscopy, 2007;23: 278-283. 10) Fu FH, Shen W, Starman JS, Okeke N and Irrgang JJ: Primary anatomic double-bundle anterior cruciate ligament reconstruction: a preliminary 2-year prospective study. Am J Sports Med, 2008;36: 1263-1274. 11) George MS, Dunn WR and Spindler KP: Current concepts review: revision anterior cruciate ligament reconstruction. Am J Sports Med, 2006;34: 2026-2037. 12) Georgoulis A, Ristanis S, Chouliaras V, Moraiti C and Stergiou N: Tibial rotation is not restored after ACL reconstruction with a hamstring graft. Clin Orthop Relat Res, 2007;454: 89-94. 13) Hall MP, Ryzewicz M, Walsh PJ and Sherman OH: Risk of iatrogenic injury to the peroneal nerve during posterolateral femoral tunnel placement in double-bundle anterior cruciate ligament reconstruction. Am J Sports Med, 2009;37: 109-113. 14) Ishibashi Y, Tsuda E, Fukuda A, Tsukada H and Toh S: Intraoperative biomechanical evaluation of anatomic anterior cruciate ligament reconstruction using a navigation system: comparison of hamstring tendon and bonepatellar tendon-bone graft. Am J Sports Med, 2008;36: 1903-1912. 15) Kim DK and Park WH: Clinical measurement of muscle strength and laxity in relation to dynamic postural stability in anterior cruciate ligament deficient knees. J Kor Sports Med, 2007;25: 92-97. 16) Kim SJ, Jo SB, Kumar P and Oh KS: Comparison of single- and double-bundle anterior cruciate ligament reconstruction using quadriceps tendon-bone autografts. Arthroscopy, 2009;25: 70-77. 17) Kondo E and Yasuda K: Second-look arthroscopic evaluations of anatomic double-bundle anterior cruciate ligament reconstruction: relation with postoperative knee stability. Arthroscopy, 2007;23: 1198-1209. 18) Kondo E, Yasuda K, Azuma H, Tanabe Y and Yagi T: Prospective clinical comparisons of anatomic double-bundle versus single-bundle anterior cruciate ligament reconstruction procedures in 328 consecutive patients. Am J Sports Med, 2008;36: 1675-1687. 19) Lie D, Bull A and Amis A: Persistence of the mini pivot 109
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