A 40 years old female was admitted to our hospital with a history of severe pain in the left forearm and left ankle following tril injury. She had difficulty in walking and a swelling in right upper leg. She had pain in the ankle along with painful movements of the ankle joint for about two years. Relevant abnormal biochemical parameters were -raised serum calcium (11.9 mg/dl ), raised alkaline phosphatase (717 U/L), low inorganic phosphorus (1.3 mg/dl) and raised serum parathyroid hormone (1265 pg/l). Protein electrophoresis for M band was negative. X-ray of right leg is given below. What is the most common site of lesion shown above?