Functional Anatomy and Biomechanics of Hip and Pelvis Region Flashcards
1
Q
Introduction
A
- hip is 2nd largest joint in body
- hip establishes link between LE and trunk: absorbs high forces, supports body’s mass
- LE links with trunk at pelvic girdle
- any movement in trunk pelvis or LE involves/influences hip joint
- important to evaluate movement and actions of both limbs, pelvis, and trunk: rather than to focus on single joint, improves evaluation, treatment, and outcomes
- one area in ____ system with noticeable differences between sexes: female pelvis typically lighter, thinner and wider than in males; this can affect motion in the trunk, pelvis, and LE
2
Q
Osteology
A
- pelvis: fibrous union of 3 bones
- ilium superior, ischium posteroinferior, pubis anterior inferior
- separate at birth but typically fused by 15-17 years
- proximal femur
3
Q
The Pelvis
A
- ilium, pubis, and ischium
- right and left sides joint sacrum to form a ring or hoop aka pelvis or pelvic girdle
- connect anteriorly through pubic symphysis
- connect posteriorly through sacrum
4
Q
Ilium
A
- landmarks of note on external surface: ASIS and AIIS, iliac crest, PSIS and PIIS, greater sciatic notch and greater sciatic foramen
- landmark on ote on internal surface: iliac fossa, auricular surface, iliac tuberosity
5
Q
Pubis
A
- landmarks of note:
- superior pubic ramus
- body
- pectineal line
- pubic tubercle
- inferior pubic ramus
- symphysis pubis
6
Q
Ischium
A
- landmarks of note:
- ischial spine
- lesser sciatic notch
- lesser sciatic foramen
- ischial tuberosity
- ischial ramus
7
Q
Acetabulum
A
- formed at junction of the 3 bones in hip
- located above obturator foramen
- concave joint surface
- joins with femoral head
8
Q
Acetabular Orientation
A
- center edge angle: aka angle of wilberg 35-50* provides best containment of femoral head
- acetabular anteversion angle ~20* marked variation of this angle can contribute to dislocation
9
Q
Femur
A
- landmarks of note:
- femoral head
- femoral neck
- intertrochanteric line
- greater trochanter
- lesser trochanter
- intertrochanteric crest
- quadrate tubercle
- linea aspera
- spiral line
- gluteal tuberosity
- adductor tubercle
10
Q
Femoral Angle of Inclination
A
- measured angle
- between femoral neck and medial side of femoral shaft
- typically ~125* in mature skeleton ~140-150* at birth
- influences: effectiveness of hip abductors, limb length, forces imposed on hip joint
- variations in adulthood: coxa vara (<125) coxa valgus (>125)
11
Q
Femoral Torsion Angle
A
- another measured angle
- describes the “twist” between femoral neck and femoral shaft
- normal anteversion ~10-15* anterior to frontal plane
- some have structural variation from normal anteversion: may affect individual movement patterns or function
- excessive anteversion ~35* anterior to frontal plane
- retroversion ~0* to frontal plane
- individual may demonstrate some NM compensations for structural variations
12
Q
Key Points on Angle of Inclination/Femoral Torsion
A
- both identified with diagnosti imaging
- neither can changed by PT in adults
- we can change movement patterns: place less stress on area, better help to compensate for structural variation, etc; strengthen target muscles, stretch target muscles
- important to differentiate things PT can change from those it can’t
13
Q
Pubic Symphysis
A
- site where right and left sides of pelvis connect
- cartilaginous joint with fibrocartilage joint
- end of each pubis covered with hyaline cartilage
- pubic ligament supports pubic symphysis: anterior, posterior, and superior sides of joint
- limited motion at pubic symphysis
14
Q
Sacroiliac Joint
A
- connects pelvis to sacrum
- synovial joint with strong ligamentous support
- these ligaments are the strongest in the body
- transmits force between LE and spine
- movement occurs at SI joint: varies considerably between individuals and sexes
- males: have thicker stronger ligaments; 3 of 10 have fused SI joints
- females: have greater ligamentous laxity
15
Q
SI Joint Motion
A
- sacrum is actually 5 fused vertebrae
- top of sacrum is base
- sacral flexion occurs when base moves anteriorly aka nutation, occurs with lumbar extension
- sacral extension occurs when base moves posteriorly aka counternutation occurs with lumbar flexion
- sacral torsion occurs with rotation of the left and right halves about the medial lateral axis: right rotation occurs if anterior surface of sacrum faces right, left rotation occurs if anterior surface of sacrum faces left
16
Q
Movements of the Pelvis
A
- described by monitoring ASIS/AIIS
- anterior tilt is forward tilting and downward movement of the pelvis
- occurs when: the trunk flexes as in standing forward bend, sitting with exaggerated lumbar arch
- posterior tilt: occurs when the trunk extends as in standing back bend, sitting in slouched position
- tuck butt (posterior tilt) vs. duck butt (anterior tilt)
- lateral tilt: right or left, aka pelvic obliquity, controlled by muscles
- rotation occurs about longitudinal axis in the horizontal plane
- as R leg swings forward pelvis rotates to the L vice versa when L leg swings forward
17
Q
Hip Joint
A
- ball and socket joint
- 3 degrees of freedom
- femoral head: 2/3 of a perfect sphere, entire head is covered by cartilage (except fovea)
- ligamentum teres attach fovea to acetabulum
- acetabulum is incomplete near inferior acetabular ligament
- a labrum helps to deepen this joint
- spongy trabecular bone in femoral head and acetabulum helps to absorb forces
- articular cartilage on femoral head is thickest centrally-most load supported here
- 70% of femoral head articulates with acetabulum 25% in glenohumeral joint
