Posterior Compartment

• Semimembraneous
  • Bony attachments:
    • 1. Ischial tuberosity
    • 2. Medial condyle of the tibia
  • Innervation: Tibial division of sciatic nerve (L5, S1, & S2)
  • Arterial supply: Branches of profunda femoral artery, may also receive inferior gluteal, & popliteal
  • Action: Flexes the knee, thigh extension
• Semitendinosus
  • Bony attachments:
    • 1. Ischial tuberosity
    • 2. Superior part of medial surface of tibia (with 2 other muscles to form pes anserine, "goose's foot")
  • Innervation: Tibial division of sciatic nerve (L5, S1, & S2)
  • Arterial supply: Branches of profunda femoral artery, may also have inf. glut., & popliteal
  • Action: Flexes the knee and thigh extension
• Biceps Femoris
  • Bony attachments:
    • 1. Longhead: ischial tuberosity
          Short head: linea aspera and lateral supracondylar ridge of femur
    • 2. Lateral side of head of fibula
  • Innervation: Longhead: tibial division of sciatic nerve (L5, S1, & S2)
                        Short head: common peroneal division of sciatic nerve (L5, S1, and S2)
  • Arterial supply: Profunda femoral artery, may also have inf. glut., & br. of popliteal
  • Action: Flexes the knee, extends the thigh
• Pes Anserine: ("goose's foot")
  • semitendonosus (posterior compartment)
  • gracilis (medial compartment)
  • sartorius (anterior compartment)