27th September 2021

A 79-year-old female presents to A&E with a fracture of the subtrochanteric femur after a minor fall

A 79-year-old female presents to A&E with a fracture of the subtrochanteric femur after a minor fall. The doctors suspect this is a pathological fracture and investigate further, finding on routine bloods that she has marked anaemia and hypercalcaemia, along with mild renal insufficiency. She is referred to haematology for further investigation, with multiple myeloma in the list of differential diagnoses.

Which of the following investigations is most helpful in the definitive diagnosis of multiple myeloma? Select ONE option only.