Why do athletes lose their explosiveness from microfracture surgery?

Deconditioning /pain: Microfracture surgery is a way to create channels for stem cells from the near by bone marrow to fill in a defect in the surface cartilage of a joint. Its most commonly done in the knee. To improve the chance of success most patients are on crutches for 6 weeks and avoid high impact activity for 4-6 months. It takes a long time to build back up muscle strength and there can still be pain.

Muscle strength loss: The many muscles involved in running and moving quickly from point "a" to point "b" are responsible for explosiveness (acceleration). Rehabilitation that is sports-specific is usally required to regain maximal functional recovery after any knee surgery, including microfracture.

Arthritis: The main reason for the loss of explosiveness is due to the fact that in essence a microfracture is arthritis of the knee. That leads to protective mechanisms to avoid pain. This is manifested in loss of the edge that elite atheletes possess. In the future, live cartilage transplant may hopefully replace this procedure.