On November 29, 2012 I had my left knee replaced. First, I want to emphasize that my recovery is going very well.

All of this unhurried time at home healing inclines me to be introspective. I’ve come to realize that my world view now uses the filter of numbers. I know the surgery is a success because all the numbers say so.

I used to take my painkillers every four hours around the clock. Now I can sleep through the night without waking up for another dose, and I can sometimes go five or six hours during the day as well. Soon I will reduce the number of tablets for each dose from three to two, and then to one, and eventually none.

My physical therapy is making a world of difference. I go to knee class with other knee surgery patients three times a week for an hour. At each session, the therapist adjusts the exercise bike in the workout room to make sure the angle of the pedals is appropriate. I know I’m improving because today the therapist changed the angle to make my leg bend more.

Twice on the days I don’t go to therapy, I review my written instructions for exercises too numerous for me to remember without notes. That one is 20 repetitions, holding the position for 10 seconds. And that one is 10 repetitions, holding for 5 seconds. The only routine I consistently remember is riding my exercise bike, a simple protocol of twice a day for 10 minutes.

At each physical therapy session, the therapist measures my range of motion. Today, she found that I have regained full extension of 0 degrees and can bend my leg to 104 degrees, an increase of 19 degrees in 7 days. She explained that my knee joint is “springy,” meaning that it’s just tight muscles that are limiting my movement now and not the prosthesis. This means that I will be able to bend my knee more with continued physical therapy and time.

All of this is a great motivator to continue diligently following my protocols for recovery. As I count the number of repetitions for each exercise and the hours between doses of medication, I find that unconsciously I have begun tracking virtually everything in my life by number—adding up how many hours I slept last night, guessing how many seconds it will take for the walk signal to change at the crosswalk on my way to physical therapy. If an ordered life by number is what is necessary for me to heal, I’ll take it.