Pelvis Bones/Joints/Ligaments Flashcards
Pelvis Functions
-Protect the internal organs
-Transmit forces from upper body onto the lower limb
-Absorb forces from lower limb
Female Pelvis is _______________ and ________________ than the male pelvis.
Shorter, Wider
Sacrum
-Wedge-shaped bone between 2 hip bones
Coccyx
Tailbone (remnant of tail human embryos have until the beginning of 8th week)
Hip
-2 hip bones
-Each hip bone has 3 regions (separated in newborn (connected with cartilage) fused in early adulthood (15-20yrs))
1. Ilium
2. Ishium
3. Pubis
What are the 3 regions of hip bone?
- Ilium
- Ishium
- Pubis
Ilium
(pl. Ilia) (yellow)
-Large, superior part (2/3rds of the bone)
Ischium
(pl. Ischia) (blue)
-Posterior, Inferior
Pubis
(pl. Pubes) (red)
-Anterior, Inferior
What structures pass through the foramen?
-Piriformis
-Sciatic Nerve
-Posterior Femoral Cutaneous Nerve
Lateral View of Pelvis Structures
-Posterior superior iliac spine (PSIS)
-Posterior inferior iliac spine (PIIS)
-Greater sciatic notch (converted into greater sciatic foramen by sacrospinous ligament)
-Body of ilium
-Ischial spine
-Lesser Sciatic notch
-Body of ischium
-Ischial tuberosity “sitting bone”
-Ramus of ischium
-Obturator foramen
-Inferior pubic ramus
-Pubic tubercles
-Superior pubic ramus (ischopubic ramus)
-Acetabulum
-Anterior inferior iliac spine (AIIS)
-Anterior superior iliac spine (ASIS)
-Iliac crest (runs from the ASIS to PSIS)
Iliac tubercle (tuberculum) (~5cm posterior to ASIS)
Obturator Foramen
-Junction of ischium-pubis forms the obturator foramen
-Partly covered by connective tissue membrane
-Opening allows nerves and blood vessels to pass through (obturator vessels and nerve)
Greater sciatic notch (converted into __________________ by __________________ ligament).
Greater Sciatic Foramen, Sacrospinous
Acetabulum
-The junction of the Ilium-ischium-pubis forms the acetabulum
-Place where thigh bone (head of femur) articulates with pelvis
Medial View Pelvis Structures
-Iliac crest
-Anterior superior iliac spine (ASIS)
-Iliac fossa
-Anterior inferior iliac spine (AIIS)
-Iliopubic eminence
-Superior pubic ramus
-Pectineal Line (Pectin Pubis)
-Pubic tubercle
-Inferior pubic ramus
-Obturator foramen
-Ramus of Ischium
-Ischial Spine
-Greater sciatic notch
-Posterior inferior iliac spine (PIIS)
-Auricular (ear) surface of the ilium (for articulation with sacrum)
-Posterior superior iliac spine (PSIS)
Anterior View Pelvis Structures
-Iliac crest
-Anterior superior iliac spine (ASIS)
-Anterior inferior iliac spine (AIIS)
-Iliopubic eminence
-Superior pubic ramus
-Obturator foramen
-Pubic tubercle
-Inferior pubic ramus
-Ischial tuberosity
-Pubic symphysis (a.k.a. symphysis pubis)
-Lesser sciatic notch
-Pectineal Line
-Ischial Spine
-Greater sciatic notch
Sacrum
Each ilium articulates with the ____________.
Sacrum
Ischiopubic rami
Combined form of ramus of the ischium and the inferior pubic ramus
Inguinal Ligament
The boundary between the lower limb and the abdomen
-ASIS and pubic tubercle are attachments of inguinal ligament
-Inguinal region is the depression between the abdomen and thigh (referred to as groin)
Hip (Coxafemoral Joint)
-Head of femur articulates with the acetabulum
-Synovial
-Multiaxial
-Ball and Socket
-Head of femur projects medially, superiorly, & anteriorly
-Acetabulum projects laterally inferiorly, & anteriorly
Available Motions at Hip Joint
-Flexion
-Extension
-Medial Rotation
-Lateral Rotation
-Abduction
-Adduction
Articular Surface of the Acetabulum
-Horseshoe Shaped
Articular Cartilage
-Covers head of the femur and the horseshoe shaped part of the acetabulum
*Articular cartilage is part of a synovial joint
Ligament of the Head of Femur
-a.k.a ligamentum teres, round ligament, foveal ligament
-Connects head of femur to the acetabulum
Acetabular Labrum
-Fibrocartilagenous lip that attached to the bony rim of acetabulum
-Functions to deepen acetabulum (make ‘socket’ a deeper socket)
Acetabular Fossa
-Centre of acetabulum
-Fossa is occupied by fat pad covered with synovium
Acetabular Notch
-Notch between the 2 ends of the horseshoe
-Passage for blood vessels
Transverse Ligament of Acetabulum
-Connects (closes) the acetabular notch
Ligaments of the Hip
-All the capsular ligaments of the hip are coiled or twisted as they pass from the pelvis to the femur (in a neutral position)
-Extension/hyperextension tightens them further making extension part of the close-packed position and a position of stability in an upright posture
-Conversely, full hip flexion with abduction is an unstable position
Iliofemoral Ligament (Y ligament)
Attaches: AIIS, acetabular rim - intertrochanteric line of femur
Checks: extension, abduction, lateral rotation
Pubofemoral Ligament
Attaches: superior pubic ramus - iliofemoral ligament
Checks: abduction
Ischiofemoral Ligament
Attaches: ischial part of acetabular rim - femoral neck and medial greater trochanter
Checks: hyperextension
Trochanteric Bursa
-Between the gluteus maximus muscle and the (postero-lateral) greater trochanter
Ischiogluteal Bursa
-Overlying the ischial tuberosity
-Weavers bottom (layman’s term for ischiogluteal bursitis) - people weaving would have to extend one leg forward then the other - the repetitive position changes put excessive pressures on the ischial tuberosity and therefore the bursa
Weavers bottom
(layman’s term for ischiogluteal bursitis)
-People weaving would have to extend one leg forward then the other - the repetitive position changes put excessive pressures on the ischial tuberosity and therefore the bursa
Iliopectineal Bursa
Between the iliopsoas muscle and the iliopubic eminence
Pubic Symphysis (a.k.a. Symphyis Pubis)
-Joint between the 2 pubic bones
-Cartilaginous Joint (there is cartilage between 2 ends)
-Fibrocartilagenous disc between 2 bones which acts as a shock absorber
-Limited movement
-Ligaments: superior pubic ligament, inferior pubic ligament
Sacroiliac Joint
-Joints between ilia and sacrum (sacrum is suspended between the ilia)
-Synovial Joints (very strong joint - capsule is strong, ligaments are strong, etc.)
*Does not fit under specific joint category
-Surfaces are irregular in shape and contour (elevations and depressions) which result in. a partial interlocking of the bones
-Limited movement (trade mobility for stability)
-Ligaments: anterior and posterior sacroiliac ligaments
Pelvis is held together by _________________.
Ligaments
Ligaments (and the pubic symphysis) progressively _____________ during pregnancy to allow passage of the fetus through the birth canal.
Relax
Iliolumbar Ligament
-TVP’s L4 & L5 to the posterior iliac crest
-Key stabilizer of L5
-Limits/checks/restricts lateral flexion
Sacrotuberous Ligament
-Posterior surface of the sacrum/coccyx to the ischial tuberosity
-Stabilizes the SI joint and provides a surface attachment for gluteus maximus
Sacrospinous Ligament
-Lateral sacrum/coccyx to the ischial spine
-Converts the greater sciatic notch into the greater sciatic foramen
