What Causes Pain In The Hips And Knees?

Hi! I am a physical therapist who just saw a pt with the following symptoms: Bilateral hip pain, bilateral knee pain, generalized muscle pain in bilateral lower extremities, bilateral finger joint and wrist pain, and recent increase in tendency to bruise. None of her muscles had flexibility issues. She is weak in lower extremities mainly after prolonged sitting. She has no rashes, joint swelling, or heat in her joints. She has history of PMR and is 58 y.o. Any advice is appreciated! Thank you!