I’m planning to have an operation called microfracture to repair an old football injury to my right knee. I’ve been told to expect a rigorous rehab program. I’m not much of an exerciser anymore now that I’m not playing ball. Can I get by without this part?

Microfracture is a method of treating defects in knee cartilage that go clear to the bone. The surgeon drills tiny holes through the cartilage into the bone. This allows the blood from inside the bone to seep into the cartilage layer. Blood clots are formed and start a healing process.

Studies show that results after microfacture are best when the patient follows a four- to six-week postoperative program. The rehab includes protected weight bearing on that leg and continuous passive motion (CPM).

With CPM, your leg is strapped into a machine that slowly bends and straightens your knee. You can expect to spend six to eight hours (or more) each day on CPM. Based on the results of studies done so far, some surgeons consider patients at too great a risk for failure if they don’t want to follow the expected post-op rehab program.

This program is not strenuous, just time consuming. Talk to your surgeon about your concerns and let him or her know your thoughts on the subject. More information about what to expect on a daily basis may help you in your decision-making process.