Anatomy and Biomechanics

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2 Introduction Increased participation= increased injury rates Females were found to be 5.4 times more likely to sustain injury than males. And females injured their ACL ad a rate of 7.8 times more than males did. People said that because of a rapid increase of participating females there was going to be a higher ratio of female injury. This was NOT true for Anterior Cruciate ligament injuries. Five non-contact mechanisms: - planting and cutting - pivoting - sudden deceleration - one step landing and knee hyperextension - straight knee landing

3 Anatomy and Biomechanics The ACL works other ligaments to control gliding and rolling. The ACL limits internal rotation of the tibia. two bands: anteromedial posterolateral. anteromedial band- tightest during knee extension posterolateral bandtightest during knee flexion.

4 Structural Factors High Q-angle and increased pelvic width are often looked to for increased knee injury rates in females. The Q-angle- formed between the vectors for the combined pull of the quadriceps femoris muscle and the patellar tendon. Q-angles exceeding 15 in men and 20 in women is considered abnormal. This is wider in women because of the wider pelvis in women. Wider pelvis= increased injury rate because of the angle of the knee and the stress put of the ACL.

5 ACL tear ACL reconstruction -The anterior cruciate ligament connects the tibia to the center of your knee. It limits rotation and forward motion of the tibia.

6 Femoral Intercondylar Notch The Femoral Intercondylar notch is the notch in front of the femur and the tibia. This notch tends to be more narrow and closer to the inside of the knee in females than in males. The narrower notch is said to be a factor in the increased ACL injury rate in females.

7 Femoral Anteversion The Femoral Anteversion is described as the rotation of the femur. It is in the transversal plane and is said to be a mechanism of Anterior Cruciate Ligament injuries. Internal Rotation of the femur predisposes an individual to excess subtalar joint.

8 Subtalar Pronation This is described as a combined motion involving subtalar eversion, foot abduction and ankle dorsiflexion. Prolonged pronation= increased internal rotation= increased joint stress= more susceptible to injury.

9 It has been suggested that joint laxity and joint injury are very related. Athletic females have been found to tend to have less ligamentous laxity than males and non athletic females. Joint laxity can also be hereditary. Joint Laxity

10 Neuromuscular Performance In 1985 it was said that the main reason behind the higher incidence of noncontact ACL injury was inadequate motor skills. When ACLs operate in isolation it can not withstand forces during sport activity, therefore motor skills and muscles must be built up to protect the ACL.

11 Hormonal/Menstrual Factors Oestrogen and progesterone receptors have been isolated in the ACL. Oestrogen secreted the ligament is much weaker and proprioceptive skills are weaker, increasing injuries. Oestrogen and progesterone levels are highest during menstruation. Therefore during the menstruation cycle is when the ACL is most susceptible.

12 To make effective prevention programs and lower injury rates we must know exactly what is going on in the knee and who is at greatest risk. Sports specific regimens and proprioceptive programs must be followed to decrease injury rate in females. Conclusion

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14 Works Cited m.nih.gov/medlineplus/ency/imagepages/8717.htm&h=320&w=400&sz=19&hl=en&start=1&usg= gi2jik2pjpz6hgtwlmw1tr4vvfy=&tbnid=ll SdiBmDS89acM:&tbnh=99&tbnw=124&prev=/images%3Fq%3Danterior%2Bcruciate%2Bligament%26hl%3Den%26safe%3Dactive%26sa%3DN wqzfvrl94axjmzp7gb1hlo9gflc=&tbnid=yjkg3yhast312m:&tbnh=113&tbnw=105&prev =/images%3fq%3danterior%2bcruciate%2bligament%26start%3d20%26ndsp%3d20%26hl%3den%26safe%3dactive%26sa%3dn 2.htm&h=346&w=306&sz=18&hl=en&start=18&um=1&usg= 9EWmJiMpno5zVbWkyMNJfjEXb3M=&tbnid=h_Iho_PswxyXoM:&tbnh=120&tbn w=106&prev=/images%3fq%3dfemoral%2bintercondylar%2bnotch%26um%3d1%26hl%3den%26safe%3dactive%26sa%3dn 2.htm&h=346&w=306&sz=18&hl=en&start=18&um=1&usg= 9EWmJiMpno5zVbWkyMNJfjEXb3M=&tbnid=h_Iho_PswxyXoM:&tbnh=120&tbn w=106&prev=/images%3fq%3dfemoral%2bintercondylar%2bnotch%26um%3d1%26hl%3den%26safe%3dactive%26sa%3dn om/%3fpage%3dlibrary%26list%3dknee%26article%3d17&h=300&w=300&sz=21&hl=en&start=10&um=1&usg= bzyczpn54qh_0hx6wxw3 YrOI6rw=&tbnid=qdWtLbsOgPI- BM:&tbnh=116&tbnw=116&prev=/images%3Fq%3Danterior%2Bcruciate%2Bligament%2Btears%26um%3D1%26hl%3Den%26safe%3Dactive = enu%3dgc_web/rightmenu.htm%26wpleftmenu%3dgc_sm/leftmenuconditions.htm%26g_cid%3d59%26g_sid%3d %26chk%3d135 63&h=443&w=300&sz=34&hl=en&start=53&um=1&usg= 4n20sKoyXWdhzhAToLubGqz4Y8o=&tbnid=Z1YogIHtwiwNFM:&tbnh=127&tbnw=8 6&prev=/images%3Fq%3Danterior%2Bcruciate%2Bligament%26start%3D40%26ndsp%3D20%26um%3D1%26hl%3Den%26safe%3Dactive%26s a%3dn nbefit.com/acl.html&usg= G72LGqL9aLl3IxnGLveK6PMXmX0=&h=320&w=400&sz=376&hl=en&start=19&tbnid=hCWpz9LaMqvMmM:&tbnh =99&tbnw=124&prev=/images%3Fq%3Dinternal%2Brotation%2Bof%2Bthe%2BACL%26gbv%3D2%26hl%3Den%26safe%3Dactive