Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content ++ ACL sprainACL partial TearACL full-thickness tear ++ 844.2 Sprain of cruciate ligament of knee717.83 Old disruption of anterior cruciate ligament ++ S83.509A Sprain of unspecified cruciate ligament of unspecified knee, initial encounterM23.50 Chronic instability of knee, unspecified knee ++ 4I: Impaired Joint Mobility, Motor Function, Muscle Performance, and Range of Motion Associated With Bony or Soft Tissue Surgery +++ Description ++ American Medical Association (AMA) has developed standard nomenclature for athletic injuries to ligamentous structures11st degree sprain: minor tear of ligament fibers2nd degree sprain: partial tear of ligament structure3rd degree sprain: complete tear of ligament +++ Essentials of Diagnosis ++ Clinical diagnosis of a partial tear1Asymmetric Lachman testNegative pivot-shift testKT-1000 arthrometer test ≤ 3mmConfirming arthroscopic observationMedial and lateral menisci and medial collateral ligament (MCL) are commonly injured with the ACL2HistoryContact injuries: typically due to application of varus or valgus force to the knee imposing a shear force on the jointRisk for injury increased by2Sudden decelerationAbrupt change in directionHyperextension of the kneeNon-contact injuries (70% of ACL injuries4) typically due to3Deceleration and change in direction (cutting maneuvers)Landing from a jump in full knee extensionPivoting with planted foot and extended kneeHyperextension/flexion of the knee +++ General Considerations ++ It is estimated that more than 250,000 ACL injuries occur in the United States each year275,000–100,000 ACL reconstructions performed annually5 +++ Demographics ++ ACL injuries reported to be 2–9 times more likely in females than in males4,6 +++ Signs and Symptoms ++ Feelings of instability in the knee7Severe pain at the time of injury 7Audible pop at the time of injury7Immediate swelling at the time of injury (effusion) +++ Functional Implications ++ Instability of the knee during weight-bearing tasksAmbulation distanceSquattingActivities requiring single-leg stance (donning lower extremity clothing)Mobility on uneven terrain +++ Possible Contributing Causes ++ Female sexTendency of females to land from a jump and change direction in a more erect posture, characterized with increased knee and hip extension3,8Tendency of females to land with increased knee valgus3,8Pelvic structure and lower-extremity alignment that result in a varied Q-angle9More narrow intercondylar notch3,9Smaller ACLs3,9Increased estrogen levels and related increase in laxity.3 (This is controversial in research literature.)Increased duration of activity and fatigue10Athletic activities in dry-weather conditions or playing on artificial turf3Increased Body Mass Index (BMI)Decreased hamstring strength relative to quadriceps3Decreased core ... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.