Transcript Hip
Review: Muscles that act on the spine Look out for the penguin!!! What muscles extend the vertebral column? Erector spinae Rotatores Multifidi Semispinalis (capitis) Quadratus Lumborum What muscles flex the spine? Rectus abdominis External oblique Internal oblique What muscle rotates the spine to the SAME side? Internal Oblique Hip Pelvic Girdle Fx of hip Supports the visceral organs (pelvic floor) Attaches lower limbs Bears weight of body when standing and moving. Bony Connections of the Pelvis - An Overview The word pelvis means “basin” It is a cylindrical structure composed of 3 articulating bones, associated muscles, and ligaments that make up the pelvic floor. Bones of the Pelvic Girdle Two hip bones: Coxa Sacrum Coccyx The Hip Bones (or Coxal Bones) The bones have 3 fused segments: 1. Ilium (in yellow) 2. Ischium (in light pink) 3. Pubis (in fushcia) Joints of the Pelvis Pelvic Girdle Articulates with Femur Articulates with Femur Articulates with the Acetabulum of the Coxa = Acetabulofemoral Joint Acetabulum The junction of these 3 segments forms the acetabulum Ischium, Ilium, Pubis The acetabulum is a deep, bony socket that articulates with the head of the femur to form the hip joint. Posterior View . Hip Joint Boney landmarks of the Hip Ischial Tuberosity – is the bony prominence most inferior and posterior on the ischium; this is the bone we call the "sitz bones" that bears weight when we sit. Medial surface of the Ilium this is the internal bowl or scoop-shaped area of the ilium that houses the internal iliac fossa. In this fossa is the location of the iliacus muscle. ) Boney landmarks of the Hip . Lateral surfaces Iliac Crest Anterior Superior Iliac Spine (ASIS) Anterior Inferior Iliac Spine (AIIS) Posterior Superior Iliac Spine (PSIS) Greater Sciatic Notch (GSN) Iliac Crest –The most superior aspect of the Ileum. You can feel this when you place your hands on your hips. It is the bone your hands rest on. Anterior Superior Iliac Spine (ASIS) this is the most anterior portion of the ilium; it is a small, sharp bony prominence. Posterior Superior Iliac Spine (PSIS) – this is the posterior bony prominence of the ilium. Greater Sciatic Notch (GSN)– this is the opening in the posterior aspect of the ilium. It provides the pathway by which the sciatic nerve passes into the lower extremity. Differences in the Pelvic Structure Female pelvis Male Pelvis Female pelvis: wider iliac crest larger pelvic bowl greater distance between ischeal tuberosities The Sacrum Made from 5 fused vertebrae. Sacrum The Sacrum articulates with the fifth lumbar vertebrae and Coccyx. Joints of the Sacrum The Sacrum also articulates with the right and left coxal bone. The Sacrum The Sacral Foramina – small openings on the sacrum through which branches of the sacral nerves pass. Sacral base – The superior surface of S1 that articulates with L5 The Sacral Promontory – upper, anterior edge of S1. The Apex of the Sacrum – this is the caudal surface of S5 and makes up the lower portion of the sacrum. Ligaments of the Pelvis: posterior view Ligaments of the Pelvis: anterior view The Sacrospinous and Sacrotuberous ligaments add stability to the pelvis though they don’t attach to the hip joint. Ileolumbar ligaments Iliofemoral Lig anteriorly strengthens the capsule Ischiofemoral Lig posteriorly strengthens the capsule Pubofemoral Lig strengthens the inferior anterior capsule Movements allowed by Hip ball and socket joint Flexion Extension Adduction Abduction Medial Rotation Lateral Rotation Transverse Abduction Transverse Adduction Hip ROM The hip has the second greatest range of motion in the human body, with the glenohumeral joint having the greatest range. Flexion Bending the joint resulting in a decrease of angle; moving the thigh or top of the pelvis forward. Hip Movements Flexion Extension Straightening the joint resulting in an increase of angle; moving the thigh or top of the pelvis backward. Hip Movements Extension Adduction Medial movement of the thigh toward the midline of the body. Hip Movements Adduction Abduction Lateral movement of thigh away from the midline of the body Hip Movements Abduction Transverse Adduction Moving the thigh inward (toward the midline) with hip bent. Hip Movements Transverse Adduction Adductors adductor magnus adductor longus adductor brevis pectineus gracilis Tensor fasciae latae Transverse Abduction Moving the thigh outward (laterally) with hip bent. Hip Movements Transverse Abduction Gluteus maximus Gluteus medius Gluteus minimus Piriformis Obturator externus Hip Movements Medial Rotation (Internal Rotation) Rotary movement around the longitudinal axis of the bone toward the center of the body; turning the thigh or pelvis inward. Hip Movements Medial Rotation (Internal Rotation) Hip Movements Lateral Rotation (External Rotation) Rotary movement around the longitudinal axis of the bone away from the center of the body - turning the thigh or pelvis outward. Gemellus superior Gemellus inferior Obturator internus Obturator externus Quadratus femoris Piriformis Gluteus maximus Gluteus medius, posterior fibers Sartorius Ileopsoas Biceps Femoris End of show www.gla.ac.uk/ibls/ fab/tutorial/anatomy/hipt.html The next three slides are from above source Biomechanics The capsular thickenings form a spiral around the hip. In extension these fibres become taut with the result that the head of the femur is held securely in the acetabulum and the joint becomes "locked" or "close-packed" - the position of maximum stability and firmness. There is a general point here: all the major joints (hip, knee, ankle) become close-packed at full extension and this coincides with the limb becoming a rigid, vertical, weight-bearing pillar. This is clearly the essential prerequisite for standing upright on two legs i.e. the adoption of bipedal stance. Biomechanics • When standing erect the centre of gravity passes behind the hip joint. This should result in hyperextension i.e. the trunk falling backwards at the hip. This is prevented by a more slouching stance, in which the centre of gravity is bought forwards, and by the iliofemoral ligament (one of the strongest ligaments in the body) which resists hyperextension.