Pelvis Biomechanics Session 15

Essays Citations Grammar Outside resources

Objectives To deduce the motions that each ligament in the pelvic girdle prevents, to analyze the structure and function relationship with regard to the pelvic girdle, and to analyze the concept of stability vs flexibility with regard to the pelvic girdle.

Sacroiliac Joint - Ligaments Primary: Anterior Sacroiliac Interosseus Short and long posterior sacroiliac Secondary: Sacrotuberous Sacrospinous

Sacroiliac Joint - Motions Anterior Tilt and Posterior Tilt Nutation (sacral flexion) and Counternutation (sacral extension) Stability vs. Mobility http://www.youtube.com/watch?v=elo2_sWBXaM

Case Study Patient complains of LBP near left SI joint L leg longer than R Gymnast with R leg dominance Which ASIS would be anteriorly rotated? Why would it also be medially rotated?

Your patient has significant posterior tilt in his pelvis but when palpating, you notice his sacrum is nutated. What ligament would be most stretched? Posterior Sacroiliac Anterior Sacroiliac Sacrospinous None of these would be stretched

Tibiofemoral Joint – Bony Variations Genu Vara and Genu Valga Will affect the amount of force transferred between the two femoral condyles – one side will carry more weight and be damaged faster Hip and ankle issues may also result

An elderly patient with noticeable genu varus walks into your clinic An elderly patient with noticeable genu varus walks into your clinic. Which side of the knee is he more likely to have osteoarthritis in? Medial Lateral

Tibiofemoral Joint – Menisci Both: Have an anterior and posterior horn to hold it to the Tibia Are attached to the capsule and Tibia on the external edge by the coronary ligaments Coronary ligaments are loose and allow menisci to pivot Are held together anteriorly by the transverse ligament Blood supply near external border, avascular near internal border Aneural except near the horns Function as shock absorbers! Medial Meniscus C shape External border is attached to the MCL and capsule Lateral Meniscus O shape External border attached to the capsule and Popliteus Muscle Posterior border is attached to the femur by the Posterior Meniscofemoral Ligament

Tibiofemoral Joint – Ligaments LAMP Lateral Collateral Ligament (Fibular Collateral) Dense and strong Medial Collateral Ligament (Tibial Collateral) Less dense, two parts, weaker Anterior Cruciate Ligament (ACL) Anterior Tibia -> Posterior Femur Posterior Cruciate Ligament (PCL) Posterior Tibia -> Anterior Femur Anterior Lateral Ligament (ALL) Lateral epicondyle -> Gerdy’s tubercle https://www.youtube.com/watch?v=RTV5Yo3E7VQ Tibiofemoral Joint – Ligaments

Which ligament(s) are you testing by pulling a patient’s tibia anteriorly relative to the femur? PCL ACL LCL ALL