Injuries膝关节损伤课件.ppt

Knee Injuries Important Structures Cruciate ligaments Collateral ligaments Menisci Articular cartilage Patellar tendon Cruciate ligaments Control anterior and posterior movements Fit inside the intercondylar fossa Collateral ligaments Control lateral movement Exposed to valgus (MCL) and varus (LCL) forces Menisci Weight distribution Without menisci the weight of the femur would be concentrated to one point on the tibia Converts the tibial surface into a shallow socket Other Important Structures Articular cartilage 1/4 inch thick tough and slick Patella and patellar tendon Tibial tuberoscity Patellofemoral groove Patella acts like a fulcrum to increase the force of the quadriceps muscles Ligaments Knee is like a round ball on a flat surface Ligaments provide most of the support to the knees Little structure or support from the bones Muscles Quadriceps - extension Hamstrings - flexion IT band from the gluteus maximus and tensor fascia latae Acute Knee Injuries Anterior Cruciate Ligament Tears Can withstand approximately 400 pounds of force Common injury particularly in sports (3% of all athletic injuries) May hear a ‘pop’ sound and feel the knee give away Types of ACL Tears Causes of ACL Injuries Cutting (rotation) Hyperextension Straight knee landing When the knee is extended, the ACL is at it’s maximal length putting it at an increased risk of tearing External factors Amount of lower body strength Footwear and surface interaction Unhappy Triad ACL Medial collateral ligament Medial meniscus Lachman Test and Anterior Drawer Test Normal knees have 2-4 mm of anterior translation and a solid end point ACL injury will have increased translation and a soft end point Women and ACL Tears Anterior Cruciate Ligament Injuries in Female Athletes: Why Are Women More Susceptible? James L. Moeller, MD; Mary M. Lamb, MD THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 4 - APRIL 97 NCAA Four times more ACL tears in women than men basketball players. Three times more in gymnast