9 months after breaking hip, suddenly have pain down my leg and stiffness. X-ray shows bone has healed and no arthritis. Why sudden change?

Sudden hip pain. Sometime xr is not enough you may need MRI to be sure no stress fracture, also it may show ligamentous or soft tissue problems.
Be carefull. Even the x-ray showed the fracture healed that dose not mean you have no problem? Many reasons. 1-possible stress fracture below the harwear level. 2-infection a at the harwear could cuase it, unusall. 3-loss harwear indifferent locations and others. Check out.