Fractured Navicular

I have a patients who suffered and undisplaced fracture of her navicular and also a chip on the anterior process of the calcaneum. She was in a NWB cast for 6 weeks.

She commenced physio with swelling and movement limitation in all directions and was still using elbow crutches.

The swelling has all but gone (she suffers from swollen feet anyway) and the movement is almost abck to normal. However, she still finds difficultly pushing off which seems to indicate calf weakness. I have had her plantarflexion against theraband initially (when WB was still an issue) and then moved onto heel raises. She is fine bilateral but really struggles unilateral. She describes it as 'her brain wants to do it but the muscle doesn't seem to be listening'

Anything I can do to speed the process up, or is it just a matter of time. Or is there something I am missing?