Gluteal Region Flashcards
What is the name of the deep fascia of the thigh?
What does it do?
What is it a site of attachment for?
Fascia lata - encloses thigh muscles
Attachment for intermuscular septae which divide the thigh into three compartments: the anterior, medial and posterior compartments.
3 compartments of thigh
Anterior
Medial
Posterior
What is the opening in fascia lata called?
What is the function of this?
Saphenous opening
- Serves as an entry point for the saphenous vein (which drains into the femoral vein) and for lymphatic vessels which drain into the superficial inguinal lymph nodes.
What do you call the thickened aspect of fascia lata?
Where does it run from and to?
Iliotibial tract (iliotibial band) Runs from iliac crest to lateral tibial condyle (knee)
Tensor fascia lata origin, insertion and innervation
Originates: anterior superior iliac spine
Inserts: between two layers of iliotibial band
Innervation: superior gluteal nerve
Function of tensor fascia lata (4)
- Assists the gluteus medius and minimus in abduction and medial rotation of the lower limb.
- It also plays a supportive role in the gait cycle.
- As a minor action, it also ‘hoists’ the fascia lata upwards which has the effect of tightening the compartments of the thigh and compressing the deep veins (e.g. femoral vein), therefore improving venous return from the lower limbs.
Describe iliotibial band problems
How can this be treated?
As the iliotibial band is in a shortened position when seated, it becomes tight easily, leading to lateral knee pain, patellar instability and other issues. This is usually treated with physiotherapy.
Treat with physio
Superficial gluteal muscles:
- Size
- Main actions
- Name the muscles
Large muscles
Abduct and extend lower limb at hip
Gluteus maximus, gluteus medius, gluteus minimus, tensor fascia lata
Deep gluteal muscles:
- Main actions
- Size of muscles
- Name the muscles
Laterally rotate lower limb
- Group of smaller muscles
Piriformis, gemellus superior, obturator internus, gemellus inferior and quadratus femoris muscles. Obturator externus is also sometimes included in this group.
Arterial supply to gluteal muscles
Superior and inferior gluteal arteries (branches of internal iliac artery)
Gluteus maximus (6)
Largest gluteal muscle
Most superficial - round shape buttocks
Originates: posterior surface of ilium, sacrum, coccyx
Insert: Superiror fibres - iliotibial tract (superficial) Inferior fibres - Gluteal tuberosity of femur (deeper)
Actions: main extensor, assists lateral hip rotation, climbing/running, extension of knee
Innervtation: Inferior gluteal nerve (L5, S1, S2)
Gluteus medius
Fan shaped
Between gluteus maximus and gluteus minimus
Originates: gluteal/posterior surface of ileum
Inserts: lateral surface of greater trochanter
Actions:- Abduction and medial rotation of the lower limb at hip joint
- It stabilises the pelvis during locomotion, preventing ‘dropping’ of the pelvis on the contralateral side.
Innervation: superior gluteal nerve (L4, L5, S1)
Gluteus minimus
Deepest and smallest superficial gluteal
Originates: ilium
Inserts: anterior aspect of greater trochanter
Actions: - Abduction and medial rotation of the lower limb at hip joint
- It stabilises the pelvis during locomotion, preventing ‘dropping’ of the pelvis on the contralateral side.
Innervation: superior gluteal nerve (L4, L5, S1)
Superior gluteal nerve injury
- Superior gluteal nerve innervates gluteus medius and minimus
- Thus a superior gluteal nerve injury will lead to weakness abducting the thigh
- The superior gluteal nerve can be injured by:
o Complications of hip surgery
o Injections to the buttock
o Fractures of the greater trochanter
o Dislocation of the hip joint - If someone with superior gluteal nerve palsy is asked to stand on their injured lower limb, the pelvis on the unsupported side descends (positive trendelenburg sign)
Piriformis
Inferior to the piriformis, Sciatic nerve emerges from pelvis
Originates: anterior surface of sacrum through greater sciatic foramen
Insert: greater trochanter
Actions: lateral rotation and abduction lower limb
Innervation: nerve to piriformis
Obturator internus
Forms lateral wall of pelvic cavity
Originates: from the medial surface of the obturator membrane (which fills the obturator foramen) and from the adjacent pubis and ischium,Travels through lesser sciatic foramen
Inserts: greater trochanter (below piriformis and superior gemellus)
Actions: lateral rotation, abduction lower limb
Innervation (nerve to obturator internus)
Superior and inferior gemelli
Two triangles
Seperated by obturator internus tendon
Superior gemelli
Originates: Ischial spine
Insert: greater trochanter above obturator internus
Actions: lateral rotation, abduction lower limb
Innervation: nerve to obturator internus
Inferior gemelli
Originates: ischial tuberosity
Insert: greater trochanter, below obturator internus
Actions: lateral rotation, abduction of lower limb
Innervation: nerve to quadratus femoris
Obturator externus
Originates: external obturator membrane, travels posterior to neck of femur
Inserts: posterior aspect of greater trochanter
Actions: adduction and lateral rotation of thigh
Innervation: obturator nerve (L2-L4)
Quadratus femoris
Flat, square
Originate: ischial tuberosity
Insert: quadrate tuberosity (on intertrochanteric line)
Action: lateral rotation
Innervation: nerve to quadratus femoris
Function of gluteal muscles (except gluteus minimus and medius)
Lateral (external) rotators of hip
GM and GM internal (medial) rotators