According to a 10-year study at the University of Delaware, hopping tests are actually a good way to assess dynamic knee stability. When combined with other tests, patients and surgeons can be guided in making the rehab-versus-surgery decision.
Some hop tests work better than others in predicting who should be treated conservatively. Four hop tests were compared: single hop, triple hop, crossover hop, and the timed hop. It appears the timed hop test may be one test able to predict which treatment to choose.
In this test, the patient hops as fast as possible to complete a six-meter distance. Adequate quadriceps strength is needed for the test. There is a relationship between successful hopping and overall knee function. Patients who successfully complete the timed hopping tests rate their own function higher.
The fact that your leg gives out from underneath you is a significant factor. This is a sign of joint instability. It does not automatically mean surgery is needed for the best outcome. Knee function after ACL injury can improve even when there is joint laxity.
The force of muscle contraction on either side of the joint can be enough to support and stabilize the joint. Neuromuscular control of the muscles can be improved. With rapid, coordinated muscle contraction, the muscles control how much the joint slips and slides forward.
To avoid surgery, you will need a specific rehab program to address motion, strength, stability, and neuromuscular control. A sports physical therapist can help you with this.