Functional anatomy and biomechanics (Lower Extremity)

Question 1

Hip angle of inclincation

Answer 1

• normal: 115 to 125 degrees
  
  • coxa valga > 125 degrees
  • cova vara <115 degrees

Question 2

Femoral neck angle

Answer 2

• angles anteriorly 10-15 degrees from frontal plane to form anterior antetorsion angle
  
  • anteversion- considered excessive if anterior antetorsion angle > 25-30 degrees
  • retroversion- considered excessive if anterior antetorsion angle < 10 degrees

Question 3

Iliofemoral ligament of hip

Answer 3

• “Y” ligament of Bigelow
  
  • two bands both starting from anterior inferior iliac spine (AIIS)
  • medial running to distal intertrochanteric line
  • lateral running to proximal aspect of intertrochanteric line
  • very strong
  • both bands taut with extension and ER, superior band taut with adduction, inferior band taught with abduction

Question 4

Pubofemoral ligament

Answer 4

• runs from iliopectineal eminence, superior rami of pubis, obturator crest, and obturator membrane, laterally blending with capsule
• inserts into same point as medial iliofemoral ligament
• taur with extension, ER, and abduction

Question 5

Ischiofemoral ligament

Answer 5

• runs from ischium and posterior acetabulum, superiorly and laterally, blending with zone articularis, and attaching to greater trochanter
• taut with medial rotation, abduction, and extension

Question 6

Inguinal ligament

Answer 6

• 12 to 14 cm long, running from anterior superior iliac spine (ASIS) medially and inferiorly, attaching to pubic tubercle
• forms tunnel for muscles, arteries, veins, and nerves

Question 7

Innervation of hip region

Answer 7

• comes from femoral, obturator, sciatic, and superior gluteal nerves

Question 8

Hip biomechanics

Answer 8

• occur in opposite directions due to convex femoral head moving within concave acetabulum