This type of arthritis, also called "degenerative joint disease," is a breakdown of the cartilage in your hip joint. As this protective cartilage wears away, bone rubs against bone. Bony growths called "bone spurs" may form in the joint. Pain from osteoarthritis can keep you from being as active as you like.
An ACL tear occurs when the ACL ligament connecting the femur and tibia becomes injured. It is often painful and causes the knee to feel unstable. An ACL tear most often occurs during athletics, but can also occur because of sudden stops, landing awkwardly, or trauma. Most often the patient will experience a popping sound at the moment the ACL tear occurs. Surgery and rehabilitation are commonly required.