Thigh bone soreness is not necessarily a sign of multiple myeloma, as there are many potential causes for this symptom. 1. Calcium deficiency and osteoporosis can lead to such symptoms. A blood calcium test and bone density measurement at the hospital can help confirm the diagnosis. Treatment with calcium supplements can alleviate the symptoms. 2. A herniated lumbar disc compressing nerves can also cause thigh bone soreness, which may be accompanied by numbness. An MRI or CT scan of the lumbar spine can help make a clear diagnosis. 3. Multiple myeloma patients may also experience bone pain, typically in the sternum and ribs, with severe pain. Patients may also have hypercalcemia, anemia, and other symptoms. Diagnosis of this disease requires tests such as immunoglobulin levels, protein electrophoresis, and bone marrow aspiration.