1. CHAPTER 9 Pelvis and Hip

2. Bones
Pelvis
Made up of the two innominate (ilium, ischium, pubis) and sacrum
Innominates come together at acetabulum

3. The bony pelvis. 1. Sacrum 2. Ilium 3. Ischium 4. Pubic bone 5
The bony pelvis. 1. Sacrum 2. Ilium 3. Ischium 4. Pubic bone 5. Pubic symphysis 6. Acetabulum 7. Obturator foramen 8. Coccyx Red line: Terminal line/pelvic brim

4. Joints
Hip
Synovial ball-and-socket (enarthrodial) joint with three degrees of freedom
Same movements as GH joint?
Acetabulum
Deep sphere rimmed by labrum
Stability compared to GH joint?
Femoral head larger than acetabulum

5. Joints Hip—osteokinematics Pelvic motion on femur
Anterior/posterior tilt—sagittal plane
Lateral tilt—frontal plane
Protraction/retraction—transverse plane

6. Joints Hip—osteokinematics Femur on pelvis
Flexion/extension—sagittal plane
Abduction/adduction—frontal plane
Medial/lateral rotation—transverse plane

7. Muscles Flexors Iliopsoas Rectus femoris Sartorius Pectineus
Only quadriceps to cross the hip
Sartorius
Pectineus
Tensor fascia latae

8. Muscles Adductors Adductor magnus Adductor longus Adductor brevis
Gracilis

9. Muscles Extensors Gluteus maximus Hamstrings Biceps femoris
Except for short head
Semitendinosus
Semimembranosus

10. Muscles
Abductors
Gluteus medius
Gluteus minimus
Tensor fascia latae

11. Muscles Lateral rotators Medial rotators Piriformis
Gemellus superior and inferior
Obturator internus and externus
Quadratus femoris
Medial rotators
No primary medial rotators of the hip

12. Factors Affecting the Role of Hip Muscles
Muscular sufficiency—multiple joints vs. single joint
Several two-joint muscles at hip
Able to create greatest tension when elongated at one and shortened at other—length/tension
Shortening at both joints will lead to active insufficiency

13. Muscle Activity Analysis of Pelvic and Hip
Flexors
Iliopsoas most powerful hip flexor

14. Muscle Activity Analysis of Pelvic and Hip
Extensors
Gluteus maximus most powerful hip extensor

15. Muscle Activity Analysis of Pelvic and Hip
Abductors
Gluteus medius strongest hip abductor