Posterior Thigh Flashcards
Posterior compartment muscles
- Biceps femoris (short/long heads)
- Semitendinosus
- Semimembranosus
- Hamstring muscles
Deeper muscles of posterior compartment
- Short head of biceps femoris
- Semimembranosus
All posterior compartment muscles originate from
- Ischial tuberosity
- EXCEPT short head of biceps femoris
All posterior compartment muscles are
- 2 joint muscles
- EXCEPT short head of biceps femoris
All posterior compartment muscles innervated by
- Tibial part of sciatic nerve
- ECXEPT short head of biceps femoris
All posterior compartment muscles supplied by
- Perforating arteries of profunda femoris
- Superior genicular branches of popliteal
- Inferior gluteal
Short head of biceps femoris blood supply
- Perforating arteries
- Lateral superior genicular artery (branch of popliteal)
Biceps femoris
- 2 heads
- Long and short
Biceps femoris LONG head origin
- Inferomedial aspect of posterior ischial tuberosity (along with semitendinosus)
- Sacrotuberous ligament
Biceps femoris SHORT head origin
- Inferior 2/3 of lateral lip of linea aspera
- Supracondylar line
Biceps femoris insertion (BOTH heads blend and have same insertion)
- Lateral aspect of fibular head
- Fibular collateral ligament
- Lateral tibial condyle
Biceps femoris LONG head innervation
- Tibial part of sciatic nerve
Biceps femoris SHORT head innervation
- Common fibular part of sciatic nerve
Biceps femoris function
- Extend thigh
- Flex knee (leg)
- Laterally rotate the knee
- (Short head only flexes and laterally rotates the knee)
Biceps femoris tendon is palpable at
- Posterolateral knee
Semitendinosus
- Long, slender distal tendon
Semitendinosus origin
- Inferomedial aspect of posterior ischial tuberosity (common with long head of biceps femoris)
- Sacrotuberous ligament
Semitendinosus insertion
- Proximal medial tibia
- Part of pes anserinus
Semitendinosus is palpable at
- Posteromedial knee when contracted
Semitendinosus function
- Extend thigh
- Flex/medially rotate the leg
Semimembranosus
- Proxmial membranous tendon
Semimembranosus origin
- Superolatral aspect of posterior ischial tuberosity
Semimembranosus insertion
- Groove on posterior aspect of medial tibial condyle
- Oblique popliteal ligament
- Fascia over popliteus muscle
Oblique popliteal ligament (one of the semimembranosus insertions)
- Attaches to lateral femoral condyle
Semimembranosus function
- Extend thigh
- Flex/medially rotate leg
Pes anserinus (“gooses foot”)
- Shape of the insertion of the 3 tendons
- Proximal, medial tibia
- One muscle from each thigh compartment
Sartorius contribution to pes anserinus
- Most anterior
- Extends more superior
Gracilis contribution to pes anserinus
- Posterior
- More superior than semitendinosus
- Slightly more anterior than semitendinosus
Semitendinosus contribution to pes anserinus
- Posteroinferior
Nerves of the posterior thigh
- Posterior cutaneous nerve of the thigh (S1-3)
- Sciatic nerve (L4-S3)
Posterior cutaneous nerve of thigh level
- S1-3
Posterior cutaneous nerve of thigh (S1-3) pathway
- Usually medial to sciatic nerve
- Travels deep to fascia lata
Posterior cutaneous nerve of thigh (S1-3) branches supply
- Posterior thigh
- Skin over popliteal fossa
- Superior calf
- Perineum
- Gluteal region
Gluteal region is also supplied by
- Inferior cluneal nerves
- Pass around inferior edge of glut max
Sciatic nerve level
- L4-S3
Sciatic nerve (L4-S3)
- Largest nerve (~ 2cm wide)
Sciatic nerve (L4-S3) passes midway between
- PSIS and ischial tuberosity
- Greater trochanter and ischial tuberosity
Sciatic nerve (L4-S3) travels deep to
- Long head of biceps femoris
Sciatic nerve (L4-S3) usually separates in
- Distal thigh/popliteal fossa
Sciatic nerve (L4-S3) separates into
- Tibial nerve (L4-S3)
- Common fibular (L4-S2)
Tibial nerve (L4-S3) travels to
- Posterior leg
Common fibular nerve (L4-S2) pathway
- Passes below biceps femoris tendon
- Around head of fibula (palpable)
Sciatic nerve (L4-S3) innervates
- Posterior thigh, leg, and foot muscles
- Cutaneous innervation of most leg/foot
Sciatic nerve (L4-S3) varies in relationship to
- Piriformis muscle
Arteries of the posterior thigh
- Inferior gluteal
- Perforating arteries
- Popliteal artery
Inferior gluteal artery is located
- Inferior to piriformis
Inferior gluteal artery can give off artery to
- Sciatic nerve
- Supplies sciatic nerve
Inferior gluteal artery branches supply
- Gluteus maximus
- Deep gluteal muscles
- Proximal hamstring muscles
Proximal hamstring muscles receiving blood supply from inferior gluteal artery
- Long head of biceps femoris
- Semitendinosus
- Semimembranosis
Perforating arteries branch from
- Deep artery of thigh (deep femoral/profunda femoris)
Perforating arteries pierce
- Adductor magnus
Perforating arteries supply
- Posterior thigh compartment
- Inferior gluteus maximus
Popliteal artery supplies
- Distal aspect of posterior thigh muscles
- Knee joint