Lecture 1: Innominate Lecture Flashcards
What 2 forces hold the pubic symphysis together?
Extermely strong posterior ligaments and articulation at the sacroiliac joint
What are the 2 major significant pelvic structures influencing lower extremity circulation and drainage?
- Pelvic diaphragm
- Inguinal area
What part of the innominate is composed of bone from 3 different ossification centers?
Acetabulum
True ligaments vs. accessory ligaments?
True: from bone to bone
Accessory: attach at another ligament, a tendon or other fascia
What are the major Anterior Pelvic ligaments and what are their connections?
Sacrospinous: sacrum to spine of the ischium
Iliolumbar: from ilia to 5th lumbar vertebae
Anterior Sacroiliac: covers much of sacroiliac joint
Inguinal: ASIS to superior pubic rami
What are the major Posterior Pelvic ligaments and what are their connections?
Sacrotuberous: sacrum to ischial tuberosity
Posterior Sacroiliac: covers much of the sacraliliac joint
Which innominate ligament has a gluteus maximus attachment, tendon of the bicepts femoris attachment, and runs from the lower sacral tubercles to ischial tuberosity?
Sacrotuberous ligament (STL)
Function of the Iliolumbar ligament; which ligament does it blend with?
- Stabilization of L5
- Stabilizes anterior motion of lumbar spine
- Restricts anterior and rotary motio of L5
- Blends with the upper part of the anteror SI ligament
What type of joint is the Pubic Symphysis; what are the characteristics?
- Secondary cartilaginous joint
- Surfaces of the articulating bones are covered w/ hyaline cartilage and the bones are united by strong fibrous CT and/or fibrocartilage
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What pelvic ligament forms the major bond between the bone, filling irregular space posterosuperior to the joint?
Interosseous Sacroiliac Ligament
During heel strike which way is the innominate rotated on the leg/foot making contact; how about the contralateral leg (toeing off); which of these processes is active and which is passive?
- Posterior innominate rotation (active process)
- Contralateral = anteiror innominate rotation (passive process)
Which muscles contract to flex the LE at the hip and which causes posterior innominate rotation?
- Iliopsoas and quadriceps femoris were contracted to flex LE at the hip
- Iliopsoas contraction and motion of the swing phase both act upon the innominate to cause posterior rotation
What occurs to the innomincate during the toe off phase of walking?
Anterior rotation of the innominate, which is mainly a passive process
Which muscles are involved in anterior innominate rotation during the gait cycle; which are the main and which aid in the process?
- Iliopsoas elongates allowing anterior rotation of the innominate
- Gluteus maximus and hamstrings contract to extend the LE at the hip
- Erector spinae and Quadratus Lumborum contraction aids anterior innominate rotation
What are the Major and Minor hip flexors?
Major:
1) Iliacus
2) Psoas
Minor:
1) Rectus femoris
2) Sartorius
What are the Hip Extensors?
- Gluteus Maximus
Hamstrings
1) Biceps femoris
2) Semitendonosis
3) Semimembranosis
Dysfunction of which muscles may cause an anterior rotation of the innominate and/or inferior shear at the pubes?
- Rectus femoris
- Iliacus
- Ipsilateral adductor group
Tension in which muscle may lead to posterior rotation of the innominate and affect pelvic mechanics?
Hamstrings
What are the major hip abductor muscles?
- Gluteus medius
- Gluteus Minimus
- Tensor Fascia Lata
What are the 3 major hip ADductors and 2 minor?
Major:
1) Adductor Magnus
2) Adductor Brevis
3) Adductor Longus
Minor:
1) Sartorius
2) Pectineus
ADductors limit which motion of the pelvis?
Lateral movement
Which rotator is the ONLY one that connects directly to the hip; contraction of this muscle may cause?
- Piriformis
- May cause sciatica
What is the function of piriformis during hip flexion and hip extension?
- ABductor (some int. rot) when the hip is flexed
- An external rotator when the hip is extended
Trendelenburg gait pattern is caused by weakness of which muscles; supplied by which nerve?
- ABductor muscles: gluteus medius and gluteus minimus
- Superior gluteal n.
Which muscles act as external rotators of the hip?
- Piriformis (when hip extended)
- Superior and inferior Gemelli
- Obturator internus and externus
- Quadratus Femoris
Dysfunction of which muscle may produce symptoms similar to a groin pull or hernia, by irritating which nerves?
- Quadratus lumborum
- Irritating the ilioinguinal and iliohypogastric nerves (L1)
What is the landmark for determining pubic shears?
Palpating the superior aspect of the pubic ramus
