Strained Leg Muscle Anatomy
To better understand leg strain, it helps to understand the anatomy of the leg.
The entire leg contains four bones:
The thigh contains the largest bone in the body, called the femur. The femur begins at the hip and ends at the knee. The muscles of the thigh control movement of the knee and hip. The patella, or kneecap, protects the front of the knee.
The lower leg contains two long bones, called the tibia and fibula. The muscles of the lower leg control movement of the foot and ankle.
Leg anatomy examples:
- Anderson SJ. Lower extremity injuries in youth sports. Pediatr Clin North Am. 2002 Jun;49(3):627-41. 
- Beiner JM, Jokl P. Muscle contusion injury and myositis ossificans traumatica. Clin Orthop Relat Res. 2002 Oct;(403 Suppl):S110-9. 
- Kirkendall DT, Garrett WE Jr. Clinical perspectives regarding eccentric muscle injury. Clin Orthop Relat Res. 2002 Oct;(403 Suppl):S81-9. 
- Russell GV Jr, Pearsall AW 4th, Caylor MT, Nimityongskul P. Acute compartment syndrome after rupture of the medial head of the gastrocnemius muscle. South Med J. 2000 Feb;93(2):247-9.