"Once I get into a stride I forget about the discomfort but initially I'm very tentative in my steps."

That sounds so familiar! My "iffiness" is at its most bothersome after I've been sitting for a while, and "a while" can be a mere 15 minutes. I'm especially aware of my odd way of walking (John Clease, are you listening?) when I've been sitting in a doctor's waiting room and called by the nurse: my getting up and crossing the waiting room can be downright funny … if only it were funny!