Hip Mechanics
Transcript of Hip Mechanics
![Page 1: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/1.jpg)
Osteokinematics: Sagittal Plane Motions of the femur at
the hip joint
Flexion: 90o-135o
Extension: 0o-30o
Role of 2 joint muscles?
![Page 2: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/2.jpg)
Osteokinematics: Frontal Plane Motions of the femur at
the hip joint
Abduction: 30o-50o
Adduction: 10o-30o
Role of 2 joint muscles?
![Page 3: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/3.jpg)
Osteokinematics: Transverse Plane Motions of the femur at
the hip jointIR (extension*): 35o-45o
(Luttgens & Hamilton)IR (flexion**): 30o-45o
ER (extension*): 45o-50o
(Luttgens & Hamilton)ER (flexion**): 45o-60o
*Extension = Neutral -Terminal **Flexion = 900
![Page 4: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/4.jpg)
Osteokinematicmotions of the femur at the hip joint during functional activities
*
**
![Page 5: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/5.jpg)
D. Neumann – Kinesiology of the MS System
Hip Arthrokinematics
![Page 6: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/6.jpg)
Osteokinematics: Sagittal plane Motions of the Pelvis at the Hip Joint
![Page 7: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/7.jpg)
Osteokinematics: Frontal plane Motions of the Pelvis at the Hip Joint
![Page 8: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/8.jpg)
Osteokinematics: Transverse Plane Motions of the Pelvis at the Hip Joint
![Page 9: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/9.jpg)
Open Kinematic Chain Motions: LumboPelvic Rhythm
![Page 10: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/10.jpg)
Closed Kinematic Chain MotionsThe system now strives
to keep the head & trunk upright
lumbar spine & pelvis motion will now generally be opposite of that during lumbar-pelvic rhythm
![Page 11: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/11.jpg)
Acetabular Spatial OrientationFaces laterallyFaces anteriorly
18.5o males21.5o women
Faces inferiorly22o - 42o range38o in males35o in females
![Page 12: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/12.jpg)
3 Acetabular Changes With Aging:
Ossification of the articulation of the three bones of the pelvisincreased “central stability”
Decreased acetabular “roundness”reduced co-aptation
Increased Central Edge Angleincreased superior stability
![Page 13: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/13.jpg)
Structure of the Proximal FemurFemoral Head
more spherical than
acetabulum
fovea capitis
Spatial Orientation
![Page 14: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/14.jpg)
Structure of the Proximal Femur: Angle of ?
Angle of InclinationFrontal plane angulation b/t the
shaft & neck of femurContributes to the normal
valgus position of the kneeDecreases with age
150o early infancy125o in adults120o in elderly
![Page 15: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/15.jpg)
Abnormal Femoral Inclination Angle
![Page 16: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/16.jpg)
Coxa ValgaIncrease leg length produces hip adductionIncrease “pre load” to hip abductorsDecrease moment arm of abductors
![Page 17: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/17.jpg)
Coxa Vara leg length
Relative hip abduction
Poor hip abductor length tension relationship
Impingement may limit abduction ROM
Stress concentration superior contact area
![Page 18: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/18.jpg)
Coxa Vara: congenital, developmental or traumatic
![Page 19: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/19.jpg)
Structure of the Proximal Femur: Angle of ?
![Page 20: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/20.jpg)
>15o Angle of Torsion or Version: Anteversion or Medial Femoral Torsion
![Page 21: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/21.jpg)
Abnormal Angles of VersionEckoff DG: Orth Cl NA: 1994
Femoral anteversion decreases with ageBut if anteversion is excessive at birth it will
generally persist throughout lifetime
![Page 22: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/22.jpg)
Excessive AnteversionIf uncompensated anteversion will expose significant amount of femoral head anteriorly
![Page 23: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/23.jpg)
Excessive Anteversion
In order to improve congruency of joint surfaces lower extremity internal rotation may occur.
This may result in occur in “toed in” posture & gait.
![Page 24: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/24.jpg)
Abnormal Angles of Version
If angle of version is less than 15o: Retroversion or Lateral Femoral Torsion
![Page 25: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/25.jpg)
<15o Angle of Torsion or Version: Retroversion or Lateral Femoral Torsion
![Page 26: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/26.jpg)
RetroversionIf uncompensated may
expose excessive head of femur posteriorly
To improve congruency, the LE may externally rotate and appear “toed out”
![Page 27: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/27.jpg)
Position of Greatest Hip Congruency?
Combined position of:flexionabductionlateral rotation
Frequently used position for post hip dislocation immobilization
High compressive loads may be necessary to achieve maximum congruency
Is this closed pack position?
![Page 28: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/28.jpg)
Position of Maximum Hip Congruency: Impact on Ligamentous Tension
Hip flexion, lateral rotation & abduction tends to “uncoil” supporting hip ligaments
Hip ligaments are tightened by extension
![Page 29: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/29.jpg)
Frontal Plane Spatial Orientation of Hip and Stability?
Inferior angulation of acetabulum < the superior angulation of the femoral neck.
Therefore, a significant portion of the head remains uncovered.
This may lead to superior stability.
![Page 30: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/30.jpg)
IliopsoasPsoas major is attached
to anterior lumbar vertebra
Iliacus is attached to iliac fossa
Tension within this group will group will “pull” lumbar curvature anteriorly increasing lumbar lordosis
![Page 31: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/31.jpg)
Tensor Fascia Lata
Flexes & internally rotates hip Abducts if the hip is already
flexed Influence of the Thomas testMost important contribution of
TFL is maintaining tension in the ITB
![Page 32: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/32.jpg)
Tensor Fascia LataITB is considered to assist in
relieving the femur of some of the tensile loads on the shaft.
TFL (along with gluteus max) has a roll in “taking up the slack” in the ITB to enhance this function
Possible role in muscle imbalances at hip
![Page 33: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/33.jpg)
Gluteus mediusAsynchronous function of three parts
anteriormiddleposterior
All fibers abductAnt. fibers flex & IRPost. fibers extend & ERPossible role in muscle imbalances at
the hipTrochanteric Bursa
![Page 34: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/34.jpg)
AdductorsPeak isometric
torque exceeds that of abductors
Attachment to pubic ramus may be clinically significant.
Gracilis is the only adductor to cross the knee
![Page 35: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/35.jpg)
Medial Hip RotatorsThere is no muscle with a primary
function of hip medial rotation Muscles with lines of pull anterior to
the hip joint axis at some point of the ROM may contribute to the activity
TFL & anterior gluteus medius may be the most significant of these.
![Page 36: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/36.jpg)
Unilateral Stance Ipsilateral Trunk List
![Page 37: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/37.jpg)
Ipsilateral Cane Contralateral Cane
![Page 38: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/38.jpg)
Impact of a Carried Load: Contralateral Upper Extremity
EMG of hip abductor muscles increased16.8% at 5% BW load38.9% at 10% BW
load58.4% at 15% BW
loadNeumann D, PT 76: 1320-1330, 1996
![Page 39: Hip Mechanics](https://reader033.fdocuments.in/reader033/viewer/2022061123/5475d1feb4af9f980a8b5d22/html5/thumbnails/39.jpg)
EMG of hip abductor muscles decreased10.6% at 5% BW
load16.9% at 10% BW
load17% at 15% BW
loadNeumann D, PT 76: 1320-1330, 1996
Impact of a Carried Load: Ipsilateral Upper Extremity