Chapter 10 (5)

• The anterior muscles of the hip include the; Iliacus (that flexes the thigh at the hip and its portion arises from the iliac crest and fossa) and the Psoas major (that flexes the thigh at the hip and arises from lumbar vertebrae). The Iliacus and Psoas major have a common tendon on the femur.
• The Lateral and posterior muscles of the hip include the Tensor fasciae latae, which extends the knee and laterally rotates the knee, AND the Gluteus Maximus, which forms the mass of the buttock, is the prime hip extensor and provides most of the lift when you climb stairs.
• The medial (adductor) compartment of the thigh has five muscles that act as primary adductors of the thigh; the Adductor brevis, adductor longus, adductor magnus, obturator externus, and gracilis.
• The anterior (extensor) compartment of the thigh contains the large quadriceps femoris muscle AND the Sartorius which is the longest muscle in the body and is also known as the "tailor's muscle".
• The quadriceps femoris muscle is the prime mover of knee extension and flexion. It is the most powerful muscle in the body. It has four heads; rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. They all converge on a single quadriceps (patellar) tendon, extend to the patella, then continue as patellar ligament, and attach to the tibial tuberosity.
• The Posterior(flexor) compartment of the thigh contains hamstring muscles and, runs from lateral to medial. It includes the biceps femoris, semitendinosus, and semimembranosus.
• Crural muscles, acting on the foot, are separated into three compartments; the Anterior compartment, the fibular (lateral) compartment, and the posterior compartments (superficial and deep).
• The Anterior (extensor) compartment of the leg dorsiflex the ankle and prevents toes from scuffing the ground when walking. The muscles of the Anterior (extensor) compartment include; the extensor digitorum longus and the tibialis anterior.
• Gastrocnemius plantar flexes the foot and flexes the knee. The soleus plantar flexes the foot. The Triceps surae is the collective name for the gastrocnemius and the soleus. It attaches to the calcaneus via the calcaneal (Achilles) tendon, which is the strongest tendon in the body.
• The four muscles of the deep group of the posterior compartment of the muscles acting in the foot are; (1) Flexor digitorum longus that flexes phalanges. (2) Flexor hallucis longus that flexes the great toe. (3) Tibialis posterior that inverts foot. (4) Popliteus that acts on the knee.
• The Lateral (fibular) compartment of the muscles acting on the foot are two and are; the fibularis longus and the fibularis brevis. Both muscles plantarflex and evert the foot as well as provide lift and forward thrust.
• Muscles and tendons are vulnerable to sudden and intense stress. Proper conditioning and warm-up are needed. Common injuries include; compartment syndrome, Shin splints, Pulled hamstrings, Tennis elbow, Pulled groin, and Rotator cuff injury. These injuries can be treated with rest, ice, compression, and elevation. “No pain, no gain” is a dangerous misconception.