Bones, joints and muscles of pelvic and hip region Flashcards
What are the primary functions of the pelvis?
- provides a stable base of support for HAT ( head, arm and trunk complex)
- contains visceral organs
- transmits and absorbs forces to and from HAT superiorly and LE inferiorly
* Power production ( closed chain functions) rather than mobility
- - Note: Closed chain functions- distal portion is fixed
Subject Pelvis
What does the pelvic girdle consist of?
- Right and left pelvic bones joined by axial skeleton via the sacrum and fifth lumbar vertebrae posteriorly.
- Right and left hemi-pelvis meets at pubic symphysis anteriorly.
What is the pelvis made up of?
The pelvis is made up of 3 bones fused together that also contribute to the formation of the acetabulum (socket where femur fits in)
Check out pick of the pelvis’ fused Segments (3)
What are these segments?
- Anterior/superior ilium
- Posterior ischium
- anterior/inferior pubis
bony structure of pelvis: What is the greater sciatic notch?
- where the sciatic nerve travels and piriformis muscle spans across
Bony structure of pelvis: obturator foramen-what is it?
vessels and nerves travel through foramen to LE
ILIUM- Basic Info- Read it
- located anteriorly and superiorly
- Bones that you feel when you “put your hands on your hips”
- The ilium’s large surface area provides numerous attachment sites for many muscles
Description of ASIS and PSIS of ilium
- Most anterior and superior aspect of the iliac crest is anterior superior iliac spine (ASIS)
- ASIS is attachment site for sartorius and tensor fascia latae
- Posterior superior iliac spine (PSIS) follow posteriorly (Left and right PSIS)
- inferior to each PSIS is a depression which is the location of the sacroiliac joint.
What is the Ischium?
ISCHIUM
- Posterior inferior bone of the pelvis
- Contributes 40% of acetabulum
- Palpable feature: ischial tuberosity, weight bearing prominence
- ischial ramus: extends medially from body of ischium to connect to rams of pubis
What is the ischial tuberosity?
The SITS Bones
Describe features of the pubis
- Antero-inferior portion of the pelvis
- Symphysis pubis: amphiarthrodial connection between two pubic bones (JOINT)
Describe the FEMUR and its relationship w the hip
- Articulates with hip proximally and tibia at knee distally
- Longest and strongest bone in the body
- Greater trochanter: provides attachment for gluteus medius and lateral rotator muscles
- Lesser trochanter: located medially and inferiorly to greater trochanter
- linea aspera- adductor muscle origin
Describe Tibia and Fibula
- Tibia bears 90% of body weight
- Most distal aspect of tibia is the medial malleolus.
- Fibula- carries only 10% of body weight,
- Fibula is a non weight-bearing bone; main function is site for muscle attachments
HIP JOINT info AKA acetabulofemoral articulation
Acetabulofemoral articulation:
- Diarthrodial- mobility
- Triaxial- 3 planes of movement
- Ball and socket
- High congruency ( meaning hard to disclocate) and firm connective tissue between femoral head and acetabulum = Joint stability
More Info on Hip Joint
- Acetabulofemoral joint: structurally stable and very mobile.
- transmits large forces between trunk and ground
- Works with body’s locomotion system (hip abductor muscles on weight-bearing leg have to counterbalance 85% of body’s weight during each step)
- elevates and lowers the body
Hip Joint Movements- Pelvic motion on Femur
- Pelvic motion on femur (ex. leaning over to pick up and object from the floor)
1. Anterior/posterior tilt- sagittal plane
2. Lateral tilt- frontal plane
3. Protraction/ retraction- transverse plane
Hip Joint Movements: Femur on Pelvis
- Femur on pelvis (ex. Flexing hip to step up onto a step)
1. Flexion/extension-sagittal plane
2. abduction/adduction- frontal plane
3. medial/lateral rotation- transverse plane
Hip Joint (Info about the socket)
- “Superior periphery of acetabulum” (where the socket is) is lined with hyaline cartilage where weight-bearing occurs
- Inferiorly lies the acetabular fossa which is structurally deep and does not come into contact with the femoral head.
- Acetabular fossa has proprioceptors that provide joint sensory input; contains synovial fluid which is secreted for joint lubrication during weight-bearing.
Name the 5 Hip Flexor Muscles
- Iliopsoas (indigo)
- Rectus Femoris (Red)
- Sartorius (Silver)
- Pectineus (Pink)
- Tensor Fascia Latae (Teal)
Iliopsoas (INDIGO)
A: Hip flexion
O: iliac fossa, anterior and lateral surfaces of T12 through L5
I: lesser trochanter of the femur
N: iliacus portion: Femoral nerve
Psoas major portion: L2 and L3
*** Strongest hip flexor; contributes to limb shortening and advancement during swing phase of gait.
Rectus Femoris RED
A: Hip flexion, knee extension
O: Anterior inferior iliac spine (AIIS)
I: tibial tuberosity
N: Femoral nerve
Sartorius SILVER
A: Combination of hip flexion, hip abduction, lateral rotation and knee flexion
O: anterior superior iliac spine (ASIS)
I: proximal medial aspect of tibia
N: Femoral nerve
** Longest muscle in the body; brings the leg into a cross legged sitting position (by flexing, abducting and laterally rotating)
Pectineus PINK
A: Hip flexion and adduction
O: superior ramus of pubis
I: pectineal line of femur
N: femoral nerve
Tensor fascia latae TEAL
A. combined hip flexion and abduction
O: anterior superior iliac spine (ASIS)
I: lateral condyle of tibia
N: superior gluteal nerve
