Figure legends:
Figure 1: (A) Sagittal and (B) Axial MRI section showing high signal intensity on T2-weighted images in soft tissue lesions. The red arrow indicates IMM inside the supinator muscle.
Figure 2: Coronal MRI section showing high signal intensity on T2-weighted images in soft tissue lesions. The red arrow indicates intramuscular myxoma inside the supinator muscle.
Figure 3: Histopathology of IMM masses. IMM with thin capsule, fibroblasts (spindle or stellate cells) and hypocellular mucoid background containing thin scattered collagen fibers. C: Capsule, F: Fibroblasts and Co: Collagen fibers [(A1 and A2) H&E staining × 100, Scale bar = 200 μm and (B1 and B2) H&E staining × 400, Scale bar = 50 μm].
Figure 4: The surgical site of the right forearm of a 60-year-old female patient with IMM after healing of the incision site and follow-up physical examinations of supinator muscle and elbow joint functions.