Hip Joint

Question 1

Bones of the hip

Answer 1

ilium, ischium, pubis, femur
Pelvis: sacrum, pubis symphysis

Question 2

angle of inclination

Answer 2

Normal: 125 degrees
Coxa Vara: <125 degrees
Coxa Valga: > 125 degrees

Question 3

hip joint articulation

Answer 3

head of femur and acetabulum
-deep, cuplike socket…accepts the femoral head

Question 4

center edge angle

Answer 4

35 degrees
Formed by upper lateral edge of the acetabulum with center of femoral head
-Greater angle=greater coverage=greater hip stability

Question 5

Ligament of the hip

Answer 5

-Anterior: Iliofemoral
-Posterior: Ischiofemoral
-Inferior: Pubofemoral

Question 6

iliofemoral ligament

Answer 6

-Strongest, thickest ligament at hip joint
-Experience passive tension when the hip is fully extended (compensation mechanism for patients with paraplegia)

Question 7

Muscles of hip joint

Answer 7

-Extensors: Gluteus Maximus, Biceps Femoris
-Flexors: Psoas Major, Iliacus
-Adductors: Adductor brevis, adductor longus, adductor magnus, pectineus, gracilias
-Abductors: Gluteus medius, glutues minimum, tensor fasciae latae (TFL)
-External Rotation: Piriformis

Question 8

Piriformis Syndrome

Answer 8

-Commonly seen in runners or cyclists (repetitive hip external rotation)
-Sciatic nerve passes through tight piriformis muscle, causing irritation
-Could lead to painful buttocks, numb/pain along sciatic nerve (along posterior leg)

Question 9

iliotibial band

Answer 9

-Lateral thickening of fascia latae in thigh
-Taut during hip adduction
-Repetitive tension causes inflammation (ITB Syndrome)

Question 10

Hip Stability

Answer 10

-Flexors on sagitall plane provide the most torque
- Adductors and Abductors on frontal plane provide 2nd most torque

Question 11

Role of the hip abductors

Answer 11

-Hip abductor force: force that is produced by the hip abductors (contribute to torque)
-Need to balance the torque generated by body weight
-Joint reaction force: force that pass through the pivot joint (does not contribute to torque, but directly related to pressure on joint contact surface)

Question 12

Cora Vara/Valga Attributes

Answer 12

-Coxa Vara
Benefits: increase moment arm of hip abductors, increase joint stability
Drawbacks: increase stress on femoral neck under same hip abductor force, increase femoral neck stress fracture risk
-Coxa Valga
Benefits: reduce stress on femoral neck under same hip abductor force, lower femoral neck stress fracture risk
Drawbacks: reduced moment arm of hip abductors, reduced joint stability