fascial structures of the thigh/ bursa

Question 1

Fascia lata

Answer 1

• A deep membranous sheet surrounding the thigh muscles
• Extends from its proximal origins around the iliac crest + inguinal ligament to the tibia
• Deep fascia of the thigh – acts as a muscle attachment site
• Has a lateral thickening known as the Iliotibial band
• Resists outwards expansion of the thigh muscles

Question 2

Iliotibial band

Answer 2

• A longitudinal lateral thickening of the fascia lata on the lateral thigh b/w the hip bone + the leg
• Attaches to the tubercle of the iliac crest proximally + to the Gerdy’stubercle (tibia) + the lateral side of the patella + the fascia of the leg distally.
• Encloses tensor fascia lata (TFL) muscle
• Most of the Gluteus maximus tendon attaches to it posteriorly

Passively limits:
- Ipsilateral thigh abduction/pelvic drop
- Internal rotation of the tibia

Question 3

Intermuscular septa

Answer 3

• The deep fascia lata gives rise to three intermuscular septa (IMS) in the thigh: medial, posterior + lateral (strongest)
• These septa form the anterior, posterior + medial thigh muscle compartments
• The lateral IMS separates the Vastus lateralis (anterior compartment) + biceps femoris (posterior compartments)
• The medial IMS separates the Vastus medialis (anterior compartment) from the Adductors/Pectineus (medial compartment)
• The posterior IMS separates the posterior (medial hamstrings) + medial compartments (adductor magnus)
• Some of the septa also provide attachment sites for muscles

Question 4

Pes anserinus

Answer 4

• The combination of the tendinous insertions of the sartorius, gracilis + semitendinosus (SGT) on the medial side of the proximal leg
• Attaches to the proximal tibia medially
• Is continuous with the fascia of the leg
• Dynamically stabilizes the knee against valgus (abduction) + rotatory forces

Question 5

Patellar retinaculum

Answer 5

• Both the medial patellar retinaculum + the lateral patellar retinaculum are comprised of superficial + deep layers
• The medial patellar retinaculum attaches proximally to the vastus medialis, sartorius, MCL + MPFL
• The lateral patellar retinaculum attaches proximally to the iliotibial band + vastus lateralis
• Distally the retinacula attach to the medial + lateral sides of the quadriceps tendon, the patella + the patellar ligament
• These retinacula synergistically stabilize the patella

Question 6

Major bursae of the hip joint - Trochanteric bursa

Answer 6

• Can be variable normally, appearing either as just one trochanteric bursa, or divided into deep + superficial bursae
• Overlies the greater trochanter + is deep to the ITB, tensor fascia lata (TFL) + gluteal muscles at the hip
• Reduces friction b/w these overlying structures + the greater trochanter

Question 7

Major bursae of the hip joint - Iliopsoas bursa

Answer 7

• Lies b/w the hip joint anteriorly + the iliopsoas tendon
• Reduces friction b/w the anterior hip + the iliopsoas muscle.
• Communicates w/ the hip joint in 15% of cases (increased likelihood with hip joint inflammatory conditions)