Your mother?s symptoms are most suggestive of long-standing osteoarthritis of the knee, which is common after the age of 50. She should consult a doctor or orthopaedic specialist for a thorough assessment, including a knee X-ray, to confirm the severity of joint damage and guide appropriate treatment. Regular physiotherapy, muscle strengthening exercises, weight management, and supportive footwear can significantly improve knee pain and function. For pain relief, safer long-term options include paracetamol, topical anti-inflammatory gels, and occasional short courses of medicines like etoricoxib (Etoxib 90 mg) under medical supervision. If symptoms remain severe, treatments such as steroid injections or knee replacement surgery may be considered.