Multiple myeloma presenting with amyloid arthropathy as the first manifestation: Two case reports

Figure 1 Case 1: Shoulder, hip, and knee magnetic resonance imaging in 2018. A: Shoulder synovial hyperplasia; B: Knee meniscus injury; C and D: Femoral neck erosion with hyperplasia of the surrounding synovial tissue.

Figure 2 Case 2: Shoulder and wrist magnetic resonance imaging in 2017. A and B: Acromion-deltoid subcapsular effusion; C and D: Wrist joint effusion with synovial tissue hyperplasia.

Figure 3 Case 2: Hip magnetic resonance imaging and 3D imaging. A: Femoral neck erosion with surrounding synovial hyperplasia in 2018; B-D: Fracture of the right femoral neck in 2019.

Figure 4 Case 1: Hip magnetic resonance imaging and 3D imaging in 2019. A-C: Old fracture of the left femoral neck and synovial cyst around the left hip joint; D: Left femoral fracture.

Figure 5 Case 1 and Case 2: Congo red staining and immunofluorescence. A: Congo red staining ×200 (+); B: Immunofluorescence showing lambda light chain (+); C: Congo red staining ×200 (+); D: Immunofluorescence showing kappa light chain (+).