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Anterior Cruciate Ligament Double-Bundle Reconstruction With Hamstring Tendon Autografts
Technical Note
Anterior Cruciate Ligament Double-Bundle Reconstruction With Hamstring Tendon Autografts Jin Hwan Ahn, M.D., and Sang Hak Lee, M.D.
Abstract: The anterior cruciate ligament (ACL) surgical technique via a 5-strand hamstring tendon autograft is designed with a conventional single-bundle reconstruction that has shown favorable results and an additional posterolateral (PL) bundle reconstruction. The conventional single-tunnel technique is performed for the tibial tunnel, and the double-tunnel technique is performed for the femoral tunnel. The anteromedial (AM) femoral tunnel is prepared with 1 mm of the posterior femoral cortex being left over the top at the 11- to 1-o’clock position. The PL femoral tunnel is prepared with the outside-in technique by use of a 4.5-mm cannulated reamer. The AM bundle is fixed with a rigid fixation system on the femoral side, and the PL bundle is fixed to tie with the miniplate from the outside femur. A double-bundle reconstruction with 5-strand hamstring autografts, in conjunction with a conventional AM bundle and an additional PL bundle, seems to be a very effective method for the treatment of ACL instabilities. Although the long-term clinical outcome of the procedure is yet to be determined, complications including graft impingement, limitation in range of motion, and residual instability have not been observed to date in the first 38 patients who have undergone our technique. Key Words: Anterior cruciate ligament—Double-bundle reconstruction—Five-strand hamstring autografts.
A
nterior cruciate ligament (ACL) reconstruction via autogenous graft materials is a common procedure for restoring knee stability after ACL rupture. Of the various autogenous graft materials, the multiple-stranded hamstring tendon has shown results as satisfactory as the patellar tendon in recent outcome studies of ACL reconstruction. Nevertheless, a review
From the Department of Orthopaedic Surgery, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, South Korea. The authors report no conflict of interest. Address correspondence and reprint requests to Sang Hak Lee, M.D., Department of Orthopaedic Surgery, Sungkyunkwan University School of Medicine, Samsung Medical Center, 50 Ilwon-Dong, Kangnam-Ku, Seoul, 135-710, South Korea. E-mail: [email protected] © 2007 by the Arthroscopy Association of North America Cite this article as: Ahn JH, Lee SH. Anterior cruciate ligament double-bundle reconstruction with hamstring tendon autografts. Arthroscopy 2007;23:109.e1-109.e4 [doi:10.1016/ j.arthro.2006.07.016]. 0749-8063/07/2301-5464$32.00/0 doi:10.1016/j.arthro.2006.07.016
of the literature illustrates that ACL reconstruction alone leads to poor long-term outcomes in 11% to 30% of the cases studied and, more importantly, causes persistence of pivot shift in more than 15% of cases.1,2 Recently, several reports have been published describing more anatomically correct ACL reconstructions designed to reconstruct both bundles of the ACL.3-5 However, the techniques vary from surgeon to surgeon and have potential complications such as tunnel enlargement, graft impingement, and the problems of revision surgery. This article describes a double-bundle ACL reconstruction technique using 5-strand hamstring tendon autografts in conjunction with a conventional anteromedial (AM) bundle reconstruction and an additional posterolateral (PL) bundle reconstruction. SURGICAL TECHNIQUE Graft Harvesting and Preparation A 3- to 4-cm-long longitudinal skin incision is made, and the semitendinosus and gracilis tendons are har-
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 23, No 1 (January), 2007: pp 109.e1-109.e4
109.e1
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J. H. AHN AND S. H. LEE
FIGURE 1. Preparation of 5-strand hamstring tendon autografts. The AM bundle is prepared with a 4-strand double-looped hamstring autograft. The PL bundle is prepared with a single-strand semitendinosus tendon autograft and a miniplate with tying Ethibond (Ethicon, Somerville, NJ).
vested by use of a tendon stripper. A minimal graft length of nearly 28 cm for the semitendinosus tendon is necessary for the double-bundle technique. The semitendinosus tendon is cut into 2 lengths (20 cm and 8 cm). The 20-cm-long semitendinosus tendon and the resected gracilis tendon are double-looped and used for AM bundle reconstruction. The 8-cm-long semitendinosus tendon, which is the thickest portion, is single-stranded and used for PL bundle reconstruction. Usually, the diameter is 7 to 8 mm in the AM bundle and approximately 4 mm in the PL bundle (Fig 1). Notch Preparation The intercondylar notch is prepared by removing a significant portion of the anterior fat pad and synovium to allow proper visualization. The soft tissue and bone of the notch are minimally debrided through a bur inserted from the AM portal. The bur can meticulously debride the bone by a reversed maneuver. Tibial Tunnel Preparation The procedure of tibial tunneling is identical to that used for the single-bundle technique. The ACL tibial guide (Mitek, Norderstedt, Germany), with the angle set at 45°, is used to pass a guide pin from the AM tibia to a point corresponding to just posterior to the center of the tibial attachment site. When the optimal position is achieved, the guide pin is overdrilled with an appropriately sized cannulated drill. Femoral Tunnel Preparation The femoral tunnel of the AM bundle is drilled via a transtibial technique. A 5-mm-offset drill guide is
FIGURE 2. (A) Schema of double femoral tunnel. The center of the posterolateral bundle is determined at the point on the LMP line 5 to 7 mm superior to the edge of the joint cartilage. (B) The guide sheaths of the rigid fixation system are inserted to the lateral epicondylar area 1 cm above the guidewire of the PL femoral tunnel through a small skin incision. (LMP, inner margin of lateral meniscus posterior horn.)
ACL DOUBLE-BUNDLE RECONSTRUCTION
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FIGURE 3. (A) The wire loop, with wrapping of the intravenous line, is introduced from the tibial tunnel, and this passes out of the AM femoral tunnel. The simple wire loop is introduced from the PL femoral tunnel, and it passes out of the tibial tunnel (T). (B) The graft for the AM bundle is seen anteriorly. The PL bundle is observed with good tension on probing at 90° of knee flexion. (P, PCL.)
placed on the posterior aspect of the notch, which is positioned at the 11-o’clock orientation for the right knee or at the 1-o’clock orientation for the left knee. A Beath pin is positioned and then overdrilled to a depth of 30 mm; 1 to 2 mm of bone should be left between the posterior margin of the femoral tunnel and the posterior cortex of the lateral femoral condyle. Next, the PL femoral tunnel is prepared. The point of the posteromedial femoral tunnel that is located 5 to 7 mm superior to the inner margin of the lateral meniscus posterior horn at 90° flexion is marked with a microfracture awl. A 2- to 3-cm transverse incision is made directly over the lateral epicondyle of the femur, and the iliotibial band is also dissected. Under the arthroscope in the AM portal, an ACL guide tip is introduced from the anterolateral portal. The guide pin for the PL femoral tunnel is inserted from just posterior and proximal to the lateral epicondyle to the intra-articular PL point. After the insertion of a rigid fixation guide, a femoral pin is passed through the tibial tunnel. Then, 2 guide cannulas are placed through the same incision process, and the lateral femoral cortex is perforated. With care taken not to cross the PL guide pin, the point of the guide cannulas is located 1 cm superior to the PL guide pin (Fig 2). The PL femoral tunnel is drilled with a 4.5-mm reamer (Smith & Nephew Endoscopy, Andover, MA) through the guide pin. Graft Fixation After the distance of the PL femoral tunnel is measured, the PL bundle is tied by use of a miniplate (1.7
mm, 2 holes; Stryker Leibinger, Freiburg, Germany) for femoral fixation (Fig 1). Two wire loops for both bundles are passed through the tibial and femoral tunnels. First, the graft for the PL bundle is introduced through the femoral tunnel to the tibial tunnel via a wire loop. Then, the graft for the AM bundle is pulled out through the skin of the thigh by pulling out the wire loop through the tibial tunnel to the femoral tunnel (Fig 3). Next, a bioabsorbable rigid fixation pin (length, 42 mm; diameter, 3.3 mm) (Rigid Fix; Ethicon, Mitek Division, Norderstedt, Germany) is inserted into the sheath, and the femoral fixation is checked by manual traction. While tension is placed on the grafts, it should be confirmed that the grafts do not impinge during complete flexion and extension. If necessary, the notchplasty is extended. The tension of 15 to 20 lb is applied to each graft simultaneously by use of a tensioner. With the knee in 10° to 20° flexion, a bioabsorbable screw is applied to achieve tibial fixation. The tibial ends of both grafts are post-tied to a 4.5-mm cortical screw and a washer inserted near the tibial tunnel exit. DISCUSSION Various surgical procedures and graft selection for double-bundle ACL reconstruction have been presented in the literature. Yasuda et al.5 and Yagi et al.6 reported their technique of anatomic ACL reconstruction via hamstring autografts. Because the technique of anatomic ACL reconstruction requires
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a separate graft for each tunnel, the choice of graft and its fixation method requires careful consideration. In addition, limitations on the length of the graft have made the surgeons place a tunnel graft in each bone tunnel that is shorter than the tunnel graft used in the standard single-bundle ACL reconstruction. In most cases only 15 to 20 mm of a tunnel graft was positioned within either the femoral or the tibial tunnel. The implication of the tendon length limitation in the bone tunnel became a serious issue of concern. To overcome this problem, they used an extra-anatomic graft on the femoral site with EndoBottons (Smith & Nephew Endoscopy), as well as an artificial ligament. However, there have been obvious concerns over graft tunnel motion, the bungee effect, the windshield wiper effect, and suture stretch-out, all of which are associated with extra-anatomic graft fixation techniques that result in tunnel enlargement.7 The anatomic fixation close to the articular surface with direct tendon-tobone fixation and use of the rigid fixation system for femoral fixation may avoid the biomechanical disadvantages of the extra-anatomic fixation technique. It is noteworthy that our technique uses a 5-strand hamstring autograft that allows for approximately 25 to 40 mm of the graft to reside within each tunnel. CONCLUSIONS The current single-bundle techniques with hamstring autografts have been relatively successful in restoring stability to the injured knee. However, there remains considerable room for improvement. The described ACL surgical technique via a 5-strand hamstring tendon autograft is designed with a conventional single-bundle reconstruction that has shown favorable results and a PL bundle reconstruction as well. We believe that the outside-in technique used for
the PL bundle is technically an easy and effective method for restoring rotation stability and allows for more complete reconstruction than the traditional single-bundle procedure. Because the procedure has not been optimized in some aspects, biomechanical research and long-term clinical studies are considered necessary. Although the clinical outcome of the procedure is yet to be determined, complications including graft impingement, limitation in range of motion, and residual instability have not been observed to date in the first 38 patients who have undergone our technique. REFERENCES 1. Bach BR Jr, Tradonsky S, Bojchuk J, Levy ME, Bush-Joseph CA, Khan NH. Arthroscopically assisted anterior cruciate ligament reconstruction using patellar tendon autograft. Five- to nine-year follow-up evaluation. Am J Sports Med 1998;26:20-29. 2. Kocher MS, Steadman JR, Briggs K, Zurakowski D, Sterett WI, Hawkins RJ. Determinants of patient satisfaction with outcome after anterior cruciate ligament reconstruction. J Bone Joint Surg Am 2002;84:1560-1572. 3. Muneta T, Sekiya I, Yagishita K, Ogiuchi T, Yamamoto H, Shinomiya K. Two-bundle reconstruction of the anterior cruciate ligament using semitendinosus tendon with Endobuttons: Operative technique and preliminary results. Arthroscopy 1999; 15:618-624. 4. Shino K, Nakata K, Nakamura N. Anatomic anterior cruciate ligament reconstruction using two double-looped hamstring grafts via twin femoral and triple tibial tunnels. Oper Tech Orthop 2005;18:550-555. 5. Yasuda K, Kondo E, Ichiyama H, et al. Anatomic reconstruction of the anteromedial and posterolateral bundles of the anterior cruciate ligament using hamstring tendon grafts. Arthroscopy 2004;20:1015-1025. 6. Yagi M, Kuroda E, Yaoshiya S, Kurosaka M. Anatomic anterior cruciate ligament reconstruction: The Japanese experience. Oper Tech Orthop 2005;15:116-122. 7. Hoher J, Livesay GA, Ma CB, Withrow JD, Fu FH, Woo SL. Hamstring graft motion in the femoral bone tunnel when using titanium button/polyester tape fixation. Knee Surg Sports Traumatol Arthrosc 1999;7:215-219.
Anterior Cruciate Ligament Double-Bundle Reconstruction With Hamstring Tendon Autografts Jin Hwan Ahn, M.D., and Sang Hak Lee, M.D.
Abstract: The anterior cruciate ligament (ACL) surgical technique via a 5-strand hamstring tendon autograft is designed with a conventional single-bundle reconstruction that has shown favorable results and an additional posterolateral (PL) bundle reconstruction. The conventional single-tunnel technique is performed for the tibial tunnel, and the double-tunnel technique is performed for the femoral tunnel. The anteromedial (AM) femoral tunnel is prepared with 1 mm of the posterior femoral cortex being left over the top at the 11- to 1-o’clock position. The PL femoral tunnel is prepared with the outside-in technique by use of a 4.5-mm cannulated reamer. The AM bundle is fixed with a rigid fixation system on the femoral side, and the PL bundle is fixed to tie with the miniplate from the outside femur. A double-bundle reconstruction with 5-strand hamstring autografts, in conjunction with a conventional AM bundle and an additional PL bundle, seems to be a very effective method for the treatment of ACL instabilities. Although the long-term clinical outcome of the procedure is yet to be determined, complications including graft impingement, limitation in range of motion, and residual instability have not been observed to date in the first 38 patients who have undergone our technique. Key Words: Anterior cruciate ligament—Double-bundle reconstruction—Five-strand hamstring autografts.
A
nterior cruciate ligament (ACL) reconstruction via autogenous graft materials is a common procedure for restoring knee stability after ACL rupture. Of the various autogenous graft materials, the multiple-stranded hamstring tendon has shown results as satisfactory as the patellar tendon in recent outcome studies of ACL reconstruction. Nevertheless, a review
From the Department of Orthopaedic Surgery, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, South Korea. The authors report no conflict of interest. Address correspondence and reprint requests to Sang Hak Lee, M.D., Department of Orthopaedic Surgery, Sungkyunkwan University School of Medicine, Samsung Medical Center, 50 Ilwon-Dong, Kangnam-Ku, Seoul, 135-710, South Korea. E-mail: [email protected] © 2007 by the Arthroscopy Association of North America Cite this article as: Ahn JH, Lee SH. Anterior cruciate ligament double-bundle reconstruction with hamstring tendon autografts. Arthroscopy 2007;23:109.e1-109.e4 [doi:10.1016/ j.arthro.2006.07.016]. 0749-8063/07/2301-5464$32.00/0 doi:10.1016/j.arthro.2006.07.016
of the literature illustrates that ACL reconstruction alone leads to poor long-term outcomes in 11% to 30% of the cases studied and, more importantly, causes persistence of pivot shift in more than 15% of cases.1,2 Recently, several reports have been published describing more anatomically correct ACL reconstructions designed to reconstruct both bundles of the ACL.3-5 However, the techniques vary from surgeon to surgeon and have potential complications such as tunnel enlargement, graft impingement, and the problems of revision surgery. This article describes a double-bundle ACL reconstruction technique using 5-strand hamstring tendon autografts in conjunction with a conventional anteromedial (AM) bundle reconstruction and an additional posterolateral (PL) bundle reconstruction. SURGICAL TECHNIQUE Graft Harvesting and Preparation A 3- to 4-cm-long longitudinal skin incision is made, and the semitendinosus and gracilis tendons are har-
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 23, No 1 (January), 2007: pp 109.e1-109.e4
109.e1
109.e2
J. H. AHN AND S. H. LEE
FIGURE 1. Preparation of 5-strand hamstring tendon autografts. The AM bundle is prepared with a 4-strand double-looped hamstring autograft. The PL bundle is prepared with a single-strand semitendinosus tendon autograft and a miniplate with tying Ethibond (Ethicon, Somerville, NJ).
vested by use of a tendon stripper. A minimal graft length of nearly 28 cm for the semitendinosus tendon is necessary for the double-bundle technique. The semitendinosus tendon is cut into 2 lengths (20 cm and 8 cm). The 20-cm-long semitendinosus tendon and the resected gracilis tendon are double-looped and used for AM bundle reconstruction. The 8-cm-long semitendinosus tendon, which is the thickest portion, is single-stranded and used for PL bundle reconstruction. Usually, the diameter is 7 to 8 mm in the AM bundle and approximately 4 mm in the PL bundle (Fig 1). Notch Preparation The intercondylar notch is prepared by removing a significant portion of the anterior fat pad and synovium to allow proper visualization. The soft tissue and bone of the notch are minimally debrided through a bur inserted from the AM portal. The bur can meticulously debride the bone by a reversed maneuver. Tibial Tunnel Preparation The procedure of tibial tunneling is identical to that used for the single-bundle technique. The ACL tibial guide (Mitek, Norderstedt, Germany), with the angle set at 45°, is used to pass a guide pin from the AM tibia to a point corresponding to just posterior to the center of the tibial attachment site. When the optimal position is achieved, the guide pin is overdrilled with an appropriately sized cannulated drill. Femoral Tunnel Preparation The femoral tunnel of the AM bundle is drilled via a transtibial technique. A 5-mm-offset drill guide is
FIGURE 2. (A) Schema of double femoral tunnel. The center of the posterolateral bundle is determined at the point on the LMP line 5 to 7 mm superior to the edge of the joint cartilage. (B) The guide sheaths of the rigid fixation system are inserted to the lateral epicondylar area 1 cm above the guidewire of the PL femoral tunnel through a small skin incision. (LMP, inner margin of lateral meniscus posterior horn.)
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FIGURE 3. (A) The wire loop, with wrapping of the intravenous line, is introduced from the tibial tunnel, and this passes out of the AM femoral tunnel. The simple wire loop is introduced from the PL femoral tunnel, and it passes out of the tibial tunnel (T). (B) The graft for the AM bundle is seen anteriorly. The PL bundle is observed with good tension on probing at 90° of knee flexion. (P, PCL.)
placed on the posterior aspect of the notch, which is positioned at the 11-o’clock orientation for the right knee or at the 1-o’clock orientation for the left knee. A Beath pin is positioned and then overdrilled to a depth of 30 mm; 1 to 2 mm of bone should be left between the posterior margin of the femoral tunnel and the posterior cortex of the lateral femoral condyle. Next, the PL femoral tunnel is prepared. The point of the posteromedial femoral tunnel that is located 5 to 7 mm superior to the inner margin of the lateral meniscus posterior horn at 90° flexion is marked with a microfracture awl. A 2- to 3-cm transverse incision is made directly over the lateral epicondyle of the femur, and the iliotibial band is also dissected. Under the arthroscope in the AM portal, an ACL guide tip is introduced from the anterolateral portal. The guide pin for the PL femoral tunnel is inserted from just posterior and proximal to the lateral epicondyle to the intra-articular PL point. After the insertion of a rigid fixation guide, a femoral pin is passed through the tibial tunnel. Then, 2 guide cannulas are placed through the same incision process, and the lateral femoral cortex is perforated. With care taken not to cross the PL guide pin, the point of the guide cannulas is located 1 cm superior to the PL guide pin (Fig 2). The PL femoral tunnel is drilled with a 4.5-mm reamer (Smith & Nephew Endoscopy, Andover, MA) through the guide pin. Graft Fixation After the distance of the PL femoral tunnel is measured, the PL bundle is tied by use of a miniplate (1.7
mm, 2 holes; Stryker Leibinger, Freiburg, Germany) for femoral fixation (Fig 1). Two wire loops for both bundles are passed through the tibial and femoral tunnels. First, the graft for the PL bundle is introduced through the femoral tunnel to the tibial tunnel via a wire loop. Then, the graft for the AM bundle is pulled out through the skin of the thigh by pulling out the wire loop through the tibial tunnel to the femoral tunnel (Fig 3). Next, a bioabsorbable rigid fixation pin (length, 42 mm; diameter, 3.3 mm) (Rigid Fix; Ethicon, Mitek Division, Norderstedt, Germany) is inserted into the sheath, and the femoral fixation is checked by manual traction. While tension is placed on the grafts, it should be confirmed that the grafts do not impinge during complete flexion and extension. If necessary, the notchplasty is extended. The tension of 15 to 20 lb is applied to each graft simultaneously by use of a tensioner. With the knee in 10° to 20° flexion, a bioabsorbable screw is applied to achieve tibial fixation. The tibial ends of both grafts are post-tied to a 4.5-mm cortical screw and a washer inserted near the tibial tunnel exit. DISCUSSION Various surgical procedures and graft selection for double-bundle ACL reconstruction have been presented in the literature. Yasuda et al.5 and Yagi et al.6 reported their technique of anatomic ACL reconstruction via hamstring autografts. Because the technique of anatomic ACL reconstruction requires
109.e4
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a separate graft for each tunnel, the choice of graft and its fixation method requires careful consideration. In addition, limitations on the length of the graft have made the surgeons place a tunnel graft in each bone tunnel that is shorter than the tunnel graft used in the standard single-bundle ACL reconstruction. In most cases only 15 to 20 mm of a tunnel graft was positioned within either the femoral or the tibial tunnel. The implication of the tendon length limitation in the bone tunnel became a serious issue of concern. To overcome this problem, they used an extra-anatomic graft on the femoral site with EndoBottons (Smith & Nephew Endoscopy), as well as an artificial ligament. However, there have been obvious concerns over graft tunnel motion, the bungee effect, the windshield wiper effect, and suture stretch-out, all of which are associated with extra-anatomic graft fixation techniques that result in tunnel enlargement.7 The anatomic fixation close to the articular surface with direct tendon-tobone fixation and use of the rigid fixation system for femoral fixation may avoid the biomechanical disadvantages of the extra-anatomic fixation technique. It is noteworthy that our technique uses a 5-strand hamstring autograft that allows for approximately 25 to 40 mm of the graft to reside within each tunnel. CONCLUSIONS The current single-bundle techniques with hamstring autografts have been relatively successful in restoring stability to the injured knee. However, there remains considerable room for improvement. The described ACL surgical technique via a 5-strand hamstring tendon autograft is designed with a conventional single-bundle reconstruction that has shown favorable results and a PL bundle reconstruction as well. We believe that the outside-in technique used for
the PL bundle is technically an easy and effective method for restoring rotation stability and allows for more complete reconstruction than the traditional single-bundle procedure. Because the procedure has not been optimized in some aspects, biomechanical research and long-term clinical studies are considered necessary. Although the clinical outcome of the procedure is yet to be determined, complications including graft impingement, limitation in range of motion, and residual instability have not been observed to date in the first 38 patients who have undergone our technique. REFERENCES 1. Bach BR Jr, Tradonsky S, Bojchuk J, Levy ME, Bush-Joseph CA, Khan NH. Arthroscopically assisted anterior cruciate ligament reconstruction using patellar tendon autograft. Five- to nine-year follow-up evaluation. Am J Sports Med 1998;26:20-29. 2. Kocher MS, Steadman JR, Briggs K, Zurakowski D, Sterett WI, Hawkins RJ. Determinants of patient satisfaction with outcome after anterior cruciate ligament reconstruction. J Bone Joint Surg Am 2002;84:1560-1572. 3. Muneta T, Sekiya I, Yagishita K, Ogiuchi T, Yamamoto H, Shinomiya K. Two-bundle reconstruction of the anterior cruciate ligament using semitendinosus tendon with Endobuttons: Operative technique and preliminary results. Arthroscopy 1999; 15:618-624. 4. Shino K, Nakata K, Nakamura N. Anatomic anterior cruciate ligament reconstruction using two double-looped hamstring grafts via twin femoral and triple tibial tunnels. Oper Tech Orthop 2005;18:550-555. 5. Yasuda K, Kondo E, Ichiyama H, et al. Anatomic reconstruction of the anteromedial and posterolateral bundles of the anterior cruciate ligament using hamstring tendon grafts. Arthroscopy 2004;20:1015-1025. 6. Yagi M, Kuroda E, Yaoshiya S, Kurosaka M. Anatomic anterior cruciate ligament reconstruction: The Japanese experience. Oper Tech Orthop 2005;15:116-122. 7. Hoher J, Livesay GA, Ma CB, Withrow JD, Fu FH, Woo SL. Hamstring graft motion in the femoral bone tunnel when using titanium button/polyester tape fixation. Knee Surg Sports Traumatol Arthrosc 1999;7:215-219.