Chapter 13 Anatomy and Function in the Lower Extremity
Note: Unless otherwise noted, arrows in figures indicate the direction of patient motion.
Figure 13-2 Iliopsoas: Psoas and Iliacus Muscles
• Muscle attachments: Sides of T12 through L5 vertebrae to lesser trochanter of femur (psoas)
• Innervation: upper part of iliac fossa to lesser trochantor (iliacus)
• Function: Flexion of hip joint
• Physical examination: The patient lies supine with the leg flexed at the knee and hip and tries to flex the thigh against resistance.
Figure 13-4 Hip Adductor Muscles: Obturator Externus, Adductor Brevis, Adductor Longus, and Adductor Magnus
• Physical examination: The patient lies supine with the leg extended at the knee and tries to adduct the hip joint against resistance.
Figure 13-6 Sartorius Muscle
• Muscle attachments: Anterior superior iliac spine to tibia
• Innervation: Femoral nerve (L2 and L3)
• Function: Flexion and abduction of hip joint
• Physical examination: The patient sits in the “tailor’s position” (hip flexed and at maximal internal rotation, knee flexed) and attempts to flex the hip further against resistance applied at the medial surface of knee.
Figure 13-7 Quadriceps Femoris: Rectus Femoris, Vastus Medialis, Vastus Intermedius, and Vastus Lateralis Muscles
• Distal muscle attachments: Base of patella and by patellar ligament to tibial tuberosity
• Innervation: Femoral nerve (L2, L3, and L4)
• Function: Extension of knee joint
• Physical examination: With the leg flexed 90 degrees at the knee, the patient attempts to extend the knee against resistance.
Figure 13-10 Gluteus Medius, Gluteus Minimus, and Tensor Fasciae Latae Muscles
Figure 13-11 Gluteus Maximus Muscle
• Muscle attachments: Ilium, dorsal surface of sacrum and coccyx, and sacrotuberous ligament to gluteal tuberosity of femur and iliotibial tract
• Innervation: Inferior gluteal nerve (L5, S1, and S2)
• Function: Extension of thigh and lateral rotation
• Physical examination: The patient lies prone with legs extended and tries to elevate the leg against resistance.
