Normal knee anatomy
The ligaments which attach the upper leg bone (femur) to the large lower leg bone (tibia) create a hinge joint called the knee. The anterior and posterior cruciate ligaments are 2 short, strong ligaments which criss-cross each other in the middle of the joint.
Reviewed By: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.