What does a chronic fracture with cystic changes mean? specifically what are the cystic changes? it's in my foot on navicular

Non union: Chronic Fx is not really a medical term. I assume they meat non Union or maybe Old fracture vs acute. Cystic changes are most likely related to degenerative arthritic changes or chronic arthritis . The navicular bone is the first bone after the all on the medial/ inside of the foot. Ie begins the big toe and metatarsal back to just before the ankle or Talus bone. Are u a diabetic?