To improve hip capsule mobility as quickly as possible, the patient needs to put small doses of "stress" onto the capsule at home between visits and after discharge. If the patient does not assist the provider by performing some exercises or self-mobilization at home, the manual therapy will likely be less effective in its accumulation of benefit and oftentimes not effective at all.
All of us healthcare providers will recognize this adductor stretch position commonly called the butterfly stretch, but what a lot of us don't recognize is the value of this movement for "stressing" the joint capsule in a positive way. I teach this movement/position on the first day of treatment in the clinic for all my patients with hip osteoarthritis (OA). Unlike the adductor stretch, have the patient lean back against a wall or some other surface and place their hands on top of their knees. Instruct the patient to not push the knees down aggressively, but simply just use the weight of the arms to place gentle stress to open the knees further.
If the patient is more severe, have them start by sitting on a few pillows or a small step to decrease the initial stress. They can also play with how close their feet are to their body. The side with OA will stick up higher off the ground as expected so this serves as a great self-improvement metric for the patient to monitor as well. It's always wonderful when the patient comes in one treatment visit and says, "Hey, I am noticing that my knee is getting closer to the ground. It's working!" Once the patient can start to see and feel the results of their work, they'll build even more motivation to continue the consistent work necessary for improvement. That's what it is all about!