It was painful. I visited a joint/sports medical specialist doctor. Doc gave me a knee brace and some medication to reduce swelling and said to rest/stay off for a minimum of three months. I also started re-hab which included many stretches of the quad and muscles around the knee. Another part was strengthening the muscles around the knee again because of atrophy. This also helped to stabilize the knee. It was 6 months before I started exercising again and at least a year before I felt comfortable and normal. The only remaining issue is kneeling on it which that may never feel normal again.