She has a medial compartment and patellofemoral bone on bone OA (Rosenberg view will confirm Medial compartment OA). Secondly the anterior subluxation of Tibia suggests she has a non functional ACL as well which can exacerbate the pain by causing instability.
Next Steps
If pain is affecting daily life AND the patient is active, consider surgery (Total knee replacement, patient not eligible for a partial knee)
If not affecting daily life OR patient is not active then just medications, physiotherapy and palliative injection.
Health Tips
Visit a Knee specialist since clinical examination is the ultimate tool, not X rays.