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The success of anterior cruciate ligament (ACL) reconstruction: Initial tensile properties of the graft tissue; the initial fixation of the graft; the healing at the graft fixation sites, The biologic remodeling of the graft; type of postoperative rehabilitation program used.
Hamstring Tendon Autograft for ACL Reconstruction BS. Nguyễn Trọng Anh INTRODUCTION The success of anterior cruciate ligament (ACL) reconstruction: Initial tensile properties of the graft tissue The initial fixation of the graft, The healing at the graft fixation sites, The biologic remodeling of the graft, Type of postoperative rehabilitation program used. patellar tendon autograft: “gold standard” for ACL reconstruction. Fourstranded hamstring tendon autografts have become an increasingly popular graft choice for ACL reconstruction Strong points: Biomechanically, as strong as PTB Faster recovery of quadriceps muscle strength Lower incidence of donor site pain Less interference with kneeling and crawling History and Physical Examination Initial injury and subsequent injuries and previous treatment. Lachman and pivot shift tests Imaging XRAY: associated bone injury, joint space narrowing, skeletal maturity. A true lateral view in maximum hyperextension preoperative planning of the tibial tunnel in the sagittal plane. Blumensaate line MRI Associated injuries to the PL, PM, other structures. continued complaints of instability or failure of the ACL reconstruction Indications and Contraindications Acute or chronic ACL reconstruction. Pt whose occupation, lifestyle, or religion requires “knee walking,” crawling, or kneeling. Pt with patellofemoral pain or patellar tendinopathy. Pt with open growth plates Absolute contraindication: previous harvest of the hamstring tendons. Caution: Significant loss of knee flexor strength at high flexion angles at athletes require maximum flexor strength at high angles of flexion. gymnasts, wrestlers, sprinters, and American football… Femoral Fixation Options Loop suspension + cross pins provide strong femoral fixation with minimal slippage during cyclic loading: Fixation strength is high Slippage during cyclic loading is minimal The fit of the tendon in the bone tunnel is tight Femoral Tunnel Endo Linvatec guide >8 mm use the 7 mm guide 8 mm use the 6 mm guide 67mm: use the 5mm guide Positon: 2 or 10 o’clock position Transtibial tunnel: Advantages not requiring the knee to be flexed to 120 degrees during drilling of the femoral tunnel. Joint distention and the field of view in the intercondylar notch not compromised producing longer femoral tunnels in the range of 40 to 50 mm advantageous for the EndoButton CL fixation technique more graft in the femoral socket. Implant resting on the stronger cortical bone of the distal femur. Disadvantage: Free positioning of the femoral tunnel in the intercondylar notch is not possible anteromedial portal technique: Advantages:• femoral tunnel in a more anatomic position freedom to locate the starting position of the tibial tunnel anywhere along the medial surface of the tibia steeper and longer tibial tunnel Disadvantage: limits joint distention and provides a more unconventional field of view in the notch that can result in spatial disorientation. more horizontal femoral tunnel EndoButton implant's lying on the weaker metaphyseal bone of the distal femur Femoral fixation Interference screws Endobutton Cross pin Endobutton and graft passage Tension on both ends of leader sutures Securing endobutton on femoral cortex Tibial fixation Tension put on the graft Graft fixed with bioscrew The stability and ROM check. Graft tension and impingement are assessed. After confirmation that the patient has a full range of motion and negative Lachman, passing and flipping sutures are pulled out of the lateral thigh Closed drainage?? Skin closure Postoperative Management Followup The patient is seen at 7 to 10 days for suture removal and postoperative radiographs D’Amato, Bach & Wilk (Handbook of Orthopeadic Rehabilitation, Kevin E.Wilk, 2007) 5 phases Week 12: Light exercises, protect graft fixation, diminish swelling Week 24: Restore gait, ROM, prevent muscle atrophy Week 410: Muscle strength exercises, functional motion, prevent overload Week 1016: Return daily activities Week 16+: Gradually return sports activities Complications infection, deep venous thrombosis, and loss of motion premature amputation of the hamstring tendons, saphenous nerve injury, bleeding at the hamstring tendon harvest site AANA OLC Rosemont, Illinois 10/2003 THANK YOU ... program used. patellar tendon autograft: “gold standard” for ACL reconstruction. Fourstranded hamstring tendon autografts have become an increasingly popular graft choice for ACL reconstruction ... 9. Graft tensioning 10. Tibial fixation 11. Closure Hamstring Tendon Graft Harvest Hamstring Tendon Graft Harvest Graft Options: Hamstring harvest Graft Preparation Place sutures in ends... Weak link of ACL graft fixation Tibial fixation of hamstring tendon grafts remains: lower bone mineral density of the proximal tibia, fixation devices must resist shear forces applied parallel to the axis of