2Anterior Cruciate Ligament Injuries H.Mousavi Tadi,MDDepartment of orthopaedicEsfahan medical schoolFeb,2013Anterior Cruciate Ligament Injuries
3Anterior cruciate ligament (ACL) tearing 200,000 are torn each year, and 100,000 anterior cruciate ligament reconstructions are done each year in the United States.Higher in people who participate in high-risk sports, such as basketball, football, skiing, and soccer.50 percent of ACL injuries occur in combination with damage to the meniscus, articular cartilage, or other ligaments.
4ANATOMY Surrounded by synovium, extrasynovial ACL inserts on the tibial plateau, medial to the insertion of the anterior horn of the lateral meniscus in a depressed area anterolateral to the anterior tibial spine.The tibial attachment site is larger and more secure than the femoral site. The ligament is 31 to 35 mm in length and 31.3 mm2 in cross section.
5Anatomy Anteromedial bundle Smaller, tight in flexion Posterolateral bundleLarger, tight in extensionBoth bundles parallel in extensionIn flexion posterolateral insertion moves forwardBundles cross in flexionPosterolateral bundle loosens
6BIOMECHANICS Of ACL Primary restraint to anterior tibial displacement. AM band is tight in flexion.PL bulky portion of this ligament is tight in extension.The PL bundle the principal resistance for hyperextension.Tension is least at 30 to 40 degrees of knee flexion.Secondary restraint on tibial rotation and varus-valgus angulation at full extension.
7Mechanism 70% non-contact mechanisms, deceleration, jumping, cutting TwistingHyperextension30%direct contactA pop is frequently heard or feltThe patient usually has fallen to the ground and is not immediately able to get upHemarthrosis : 70% acl tearing
8PHYSICAL EXAMINATION of ACL The Lachman test is the most sensitive test for anterior tibial displacement (95% sensitivity)The pivot shift test requires a relaxed patient and an intact medial collateral ligament
10MRIAccuracy: 95% to 100%Sagittal plan external rotation knee 15 degreesBone bruises: 80%
11NATURAL HISTORY50% -70% ACL injuries occur in combination with damage to the meniscus, Osteochondral damage 21% to 31%.Abnormal loading and shear stresses in ACL–deficient knee, the risk of late meniscal injury is high .With chronic instability, up to 90% of patients will have meniscus damage 10 or more years after the initial injury.Prevalence of articular cartilage lesions increases up to 70 %in patients who have a 10-year-old ACL deficiency.
12ACL injury more common in female athlete: Neuromuscular forces and controlLanding biomechanics (conditioning and strength) play biggest rolefemales land in more extension, higher vaglus momentNotch dimensionsLigament sizeHormone levelsLigament laxityValgus leg alignmentIncreased posterior tibial slope
14Factors correlated with the need for surgery: Younger, more active patients (reduces incidence of mensical or chondral injury)Presence of associated ligamentous, chondral and meniscal conditionsActivity level/occupationSports participationOlder active patients (age >40 is not contraindication if high demand athlete)
15Surgical ProcedureBefore any surgical treatment, the patient is usually sent to physical therapy.Patients who have a stiff, swollen knee lacking full range of motion at the time of ACL surgery may have significant problems regaining motion after surgery.It usually takes three or more weeks from the time of injury to achieve full range of motion. It is also recommended that some ligament injuries be braced and allowed to heal prior to ACL surgery
18Bone–patellar tendon–bone graft Recommended for high-demand athletes and patients whose jobs do not require a significant amount of kneeling.most studies show equal or better outcomes in terms of postoperative tests for knee laxity
19Bone–patellar tendon–bone graft Postoperative pain behind the patellaPain with kneelingSlightly increased risk of postoperative stiffnessLow risk of patella fracture
20Quadruple-stranded semitendinosus-gracilis tendon graft ultimate tensile load reported to be as high as 4108 N.Fewer problems with anterior knee pain or pain after surgeryLess postoperative stiffness problemsSmaller incisionFaster recovery
21Quadruple-stranded semitendinosus-gracilis tendon graft Lack of bone to bone healingGraft elongation (stretching)Decreased hamstring strength
22Quadriceps tendon autograft Failed ACL reconstruction.High association with postoperative anterior knee pain and a low risk of patella fracture
23Graft Options BTB Hamstring Graft site morbidity Increased post op painPain with kneelingScar lengthQuad weaknessOsteoarthritisMore susceptible to graft elongation (stretching)
24Allografts Advantages : No donor morbidity Decreased surgery time and smaller incisions.Disadvantagrs:Risk of infection:Bacterial infectionhigher failure rate :23% to 34.4% in young, active patients returning to high-demand sporting activities.Autograft failure rates ranging from 5% to 10%.
25SYNTHETIC MATERIALS FOR LIGAMENT RECONSTRUCTION Gore-Tex Ligament :permanentload-bearing implantStryker Dacron Ligament :function as a permanent prosthesisKennedy Ligament Augmentation Device :function as a load-sharing implant to protect a biologic graft while it healsNo long-term studies of the artificial ligaments currently used support their routine use.Use cautiously and to reserve them for salvage procedures when autogenous grafting and reconstructive procedures have failed.
26Arch Orthop Trauma Surg. 2012 Sep;132(9):1287-97. doi: 10 Arch Orthop Trauma Surg Sep;132(9): doi: /s Epub 2012 Jun 3A systematic review of randomized controlled clinical trials comparing hamstring autografts versus bone-patellar tendon-bone autografts for the reconstruction of the anterior cruciate ligament.CONCLUSIONS: ACL reconstruction with HT autografts or BPTB autografts achieved similar postoperative effects in terms of restoring knee joint function. HT autografts were inferior to BPTB autografts for restoring knee joint stability, but were associated with fewer postoperative complications.
27Graft Placement.Femoral site are more critical because of the proximity to the center of axis of knee motionFemoral tunnel that is too anterior will result in lengthening of the intraarticular distance between tunnels with knee flexion. The practical implications of this anterior location are “capturing” of the knee and loss of flexion or stretching and perhaps clinical failure of the graft as flexion is achieved.
28Isometric” femoral position limits changes in graft length and tension during knee flexion and extension, which possibly may lead to overstretching or failure of the graftnormal anterior cruciate ligament is not isometric.bundles of the anterior cruciate ligament are under variable stress during knee motion.The anteromedial bundle undergoes higher stress during flexionposterolateral bundle undergoes higher stress during extension.
29Tibial TunnelCurrently, most surgeons advocate placement of the graft at the posterior portion of the ACL tibial insertion site near the posterolateral bundle position for best reproduction of the function of the intact ACL. This location also decreases graft impingement against the roof of the intercondylar notch with knee extension
30Tibial Tunnel< 70-75° from horizontal (in the coronal plane)
31femoral tunnelPlace the femoral tunnel lower on the lateral wall toward the 10- or 2-o’clock position or even lower, which more accurately reproduces the femoral attachment site of the ACL and provides rotational stability
33Two bundles VS one Bundle Disadvantage of 2 Bundles:Numbers of femoral tunnelsOperative timeFemoral condyle osteonecrosis, chondrolysisMore technically demandingComplicate revision procedure.
34Clin Orthop Relat Res. 2012 Mar;470(3):824-34. doi: 10 . Clin Orthop Relat Res Mar;470(3): doi: /sSingle- versus double-bundle ACL reconstruction: is there any difference in stability and function at 3-year followup?CONCLUSION:Double-bundle reconstruction of the ACL did not improve function or stability compared with single-bundle reconstruction.
35Arthroscopy. 2013 Feb;29(2):357-65. doi: 10.1016/j.arthro.2012.08.024. Outcomes of Anterior Cruciate Ligament Reconstruction Using Single-Bundle Versus Double-Bundle Technique: Meta-analysis of 19 Randomized ControlleCONCLUSIONS:Meta-analysis of random controlled trials revealed that double-bundle anterior cruciate ligament reconstruction resulted in significantly better anterior and rotational stability and higher IKDC objective scores compared with single-bundle reconstruction. However, the meta-analysis did not detect any significant differences in subjective outcome measures between double-bundle and single-bundle reconstruction, as evidenced by the Lysholm score, Tegner activity scale, and IKDC subjective score.
36Knee. 2013 Jan 7. pii: S0968-0160(12)00236-0. doi: 10. 1016/j. knee Single-bundle or double-bundle for anterior cruciate ligament reconstruction: A meta-analysiCONCLUSION:Our meta-analysis demonstrated the superiority of double-bundle over single-bundle anterior cruciate ligament reconstruction. The double-bundle ACL reconstruction technique has better outcomes in rotational laxity (pivot-shift test, KT grading and IKDC grading). However, for functional recovery, there was no significant difference between single-bundle and double-bundle reconstruction technique
37RESULTS OF ACL RECONSTRUCTION Goals:Restore normal joint motionReturn full functionPrevent secondary injuryPrevent joint arthrosis
38Am J Sports Med. 2010 Nov;38(11):2201-10. doi: 10 Am J Sports Med Nov;38(11): doi: / Epub 2010 Aug 16Knee function and prevalence of knee osteoarthritis after anterior cruciate ligament reconstruction: a prospective study with 10 to 15 years of follow-up.CONCLUSION:An overall improvement in knee function outcomes was detected from 6 months to 10 to 15 years after ACL reconstruction for both those with isolated and combined ACL injury, but significantly higher prevalence of radiographic knee osteoarthritis was found for those with combined injuries.