Lecture 3: Gluteal Region Flashcards
What are the PIN structures?
- Pudendal Nerve
- Internal Pudendal Artery
- Nerve to Obturator Internus
Tensor Fascia Lata Muscle
What are its attachments?
Origin: ASIS
Insertion: IT Tract and Lateral Condyle of Tibia
What Nerve Roots supply the Superior Cluneal Nerve?
Dorsal Rami of L1-L3
What structures exit the Greater Sciatic Foramen?
Nerves:
- Sciatic Nerve
- Superior Gluteal Nerve
- Inferior Gluteal Nerve
- Pudendal Nerve
- Posterior Femoral Cutaneous N.
- Nerve to Quadratus Femoris
- Nerve to Obturator Internes
Vessels
- Superior Gluteal Artery and Vein
- Inferior Gluteal Artery and Vein
- Internal Pudendal Artery and Vein
Piriformis Muscle
Gluteus Medius Muscle
What is its innervation and blood supply?
Innervation: Superior Gluteal Nerve (L5, S1)
Blood Supply: Deep Branch of Superior Gluteal Artery
What muscles abduct and medially rotate thigh?
- Gluteus Medius Muscle
- Gluteus Minimus Muscle
- Tensor Fascia Lata Muscle
Superior Gemelli Muscle
What is its innervation and blood supply?
Innervation: Nerve to Obturator Internus
Blood Supply: Inferior Gluteal Artery
Gluteus Maximus Muscle
What is its innervation and blood supply?
Innervation: Inferior Gluteal Nerve (L5-S2)
Blood Supply: Superficial Branch of Superior Gluteal Artery and Inferior Gluteal Artery
How does the lower extremity present when the femur (head or neck) is posteriorly dislocated?
Shortened and internally rotated
Quadratus Femoris Muscle
What is its attachments?
Origin: Lateral Border of Ischial Tuberosity
Insertion: Quadrate Tubercle on Femur
What is the Trendelenburg Sign (Duchenne’s Limp)?
Lesion of Superior Gluteal Nerve that leads to weakness of Gluteus Medius and Minimus muscles
- Pelvis drops on opposite side of injury
- Foot cannot go into swing phase
Gluteus Medius Muscle
What is its action?
- Abducts thigh
- Medially rotate thigh
- Keeps hip level when ipsilateral limb is weight-bearing and advancing the opposite limb during the swing phase
Inferior Gemelli Muscle
What is its action?
- Lateral Rotation of Extended Thigh
- Abduct Flexed Thigh
What structures go through both Greater and Lesser Sciatic Foramen?
- Pudendal Nerve
- Internal Pudendal Artery and Vein
- Nerve to Obturator Internus
Basically PIN Structures
Piriformis Muscle
What is its innervation and blood supply?
Innervation: Nerve to Piriformis (Branches of anterior rami of S1, S2)
Blood Supply: Superior and Inferior Gluteal Arteries
What ligament do the PIN structures run underneath?
Sacrotuberous Ligament
Gluteus Minimus Muscle
What is its innervation and blood supply?
Innervation: Superior Gluteal Nerve (L5, S1)
Blood Supply: Deep Branch of Superior Gluteal Artery
The nerve that innervates the Obturator Internus also innervates what other muscle?
The Superior Gemellus
Gluteus Medius Muscle
What are its attachments?
Origin: External Surface of Ilium between Anterior and Inferior Gluteal Lines
Insertion: Lateral Surface of Greater Trochanter of Femur
What muscles are supplied by the Inferior Gluteal Artery?
Gluteus Maximus
Small Lateral Rotators
Superior Hamstrings
Obturator Internus Muscle
What is its action?
- Laterally Rotation of Extended Thigh
- Abducts flexed thigh
- Steady femoral head in acetabulum
What nerve roots supply the Inferior Gluteal Nerve?
L5-S2
What structure can be damaged in some people when the Ligament of the Head of the Femur is damaged?
A Branch of the Obturator Nerve
What structures enter the Lesser Sciatic Foramen?
- Tendon of Obturator Internus Muscle
- Pudendal Nerve
- Internal Pudendal Artery and Vein
- Nerve to Obturator Internus