CHA 101L - Lab 16 (2 out of 2)

Which gluteal muscles are analogous to the rotator cuff muscle?

Gluteus medius

Gluteus minimus

Superficial layer of the gluteal region

Gluteus maximus

Gluteus medius

Gluteus minimus

Tensor fasciae latae

Gluteus maximus

Origin: Iliac crest, sacrum, sacrotuberous ligament

Insertion: Iliotibial tract, gluteal tuberosity, femoral shaft

Main actions of the gluteus maximus (on the thigh) and innervation

Extension, lateral rotation

Inferior gluteal nerve

Gluteus medius

Origin: Ilium external surface

Insertion: Greater trochanter

Main actions of the gluteus medius (on the thigh) and innervation

ABduction, medial rotation; Prevents pelvic tilt with gait

Superior gluteal nerve

Gluteus minimus

Origin: Ilium external surface

Insertion: Greater trochanter

Main actions of the gluteus minimus (on the thigh) and innervation

ABduction, medial rotation; Prevents pelvic tilt with gait

Superior gluteal nerve

Tensor fasciae latae

Origin: Iliac crest

Insertion: Iliotibial tract (IT Band)

Main actions of the tensor fasciae latae (on the thigh) and innervation

Stabilizes knee joint in extension

Superior gluteal nerve

Deep layer of the gluteal region

[P GO GO Q!]

Piriformis

Gemellus superior

Obturator internus

Gemellus inferior

Obturator externus

Quadratus femoris

Piriformis

Origin: Sacrum, sacrotuberous ligament

Insertion: Greater trochanter

Gemellus superior

Origin: ischial spine

Insertion: Greater trochanter

Oburator internus

Origin: Inner surface of obturator foramen

Insertion: Greater trochanter

Gemellus inferior

Origin: Ischial tuberosity

Insertion: Greater trochanter

Obturator externus

Origin: Outer margin of obturator foramen

Insertion: Greater trochanter

Quadratus femoris

Origin: Ischial tuberosity

Insertion: Intertrochanteric crest of femur

Main actions of the deep layer of the gluteal region

Laterally rotate thigh

Stabilize the femoral head in the acetabulum

What is the Trendelenburg gait?

Abnormal walking

Hips become over-slanted

Damage to the superior gluteal nerve -> gluteus medius and minimus damage

What is piriformis syndrome?

Compress sciatic nerve -> Pain in butt

Inflamed/Irritated piriformis can lead to sciatica

Bicep femoris - long head

Origin: Ischial tuberosity

Insertion: Fibular head

Bicep femoris - short head

Origin: Linea aspera

Insertion: Fibular head

Semitendinous

Origin: Ischial tuberosity

Insertion: Proximal medial shaft of tibia

Semimembranosus

Origin: Ischial tuberosity

Insertion: Tibia medial condyle

Which of the posterior thigh muscles are hamstrings?

All EXCEPT the bicep femoris short head

Muscles of the posterior thigh

Bicep femors (long and short head)

Semitendinosus

Semimembranosus

Muscles of the anterior thigh

Sartorius

Quadricep femoris - Rectus femoris, vastus lateralis, vastus medialis, vastus intermedius

Sartorius

Origin: ASIS

Insertion: Proximal medial shaft of tibia

Main action of sartorius

Flexes thigh

Laterally rotates thigh

Flexes legs

Rectus femoris

Origin: AIIS

Insertion: Patellar ligament to tibial tuberosity

Main action of the rectus femoris

Flexes thigh

Extends leg

Quadriceps femoris - Vastus lateralis

Origin: Greater trochanter

Insertion: Patellar ligament to tibial tuberosity

Main action of the vastus lateralis

Extend legs

Quadriceps femoris - Vastus medialis

Origin: Ischial tuberosity

Insertion: Patellar ligament to tibial tuberosity

Main action of the vastus medialis

Extends leg

Quadriceps femoris - Vastus intermedius

Origin: Anterior femoral shaft

Insertion: Patellar ligament to tibial tuberosity

Main action of the vastus intermedius

Extend legs

What is a patellar reflex?

Knee jerk reflex

Iliopsoas muscle

Origin: Lumbar vertebra, iliac crest and fossa

Insertion: Lesser trochanter of femur

Action: Flexes thigh (powerful)

Muscles of the medial thigh

Pectineus

Adductor brevis

Adductor longus

Adductor magnus (ADductor and hamstring portion)

Gracilis

Pectineus

Origin: Superior pubic ramus

Insertion: Pectineal line of femur

Main action of pectineus

ADducts thigh

Some flexion

ADductor brevis

Origin: Ischiopubic ramus

Insertion: Linea aspera (top 1/3)

Main action of ADductor brevis

ADducts thigh

Some flexion

ADductor longus

Origin: Crest of pubic symphysis

Insertion: Linea aspera (middle 1/3)

Main action of ADductor longus

ADducts thigh

Some flexion

ADductor magnus - ADductor portion

Origin: Ischiopubic ramus

Insertion: Linea aspera (lower 1/3)

Main action of the ADductor magnus - ADductor portion

ADducts the thigh

ADductor mangus - Hamstring portion

Origin: Ischial tuberosity

Insertion: ADductor tubercle of femus

Main action of the ADductor mangus - Hamstring portion

Extends thigh

Gracilis

Origin: Symphysis pubis

Insertion: Proximal medial shaft of tibia

Main action of the gracilis

ADducts thigh

Slight leg flexion