Presentation
Left-sided limping with fever. The clinician was concerned about a left hip lesion. Ultrasound and plain x-ray of the left hip were normal and MRI was arranged.
Patient Data
Erosion of the medial distal left femur with focal cortical destruction and periosteal reaction.
Normal left hip joint.
Altered marrow signal intensity of the distal left femur with low T1 and hyperintense T2 and PDFS signals. Focal destruction of the posteromedial distal femoral cortex is noted with elevated periosteum and periosteal reaction as well as subperiosteal 3.0 x 1.2 cm. cystic collection is noted with low T1 and hyperintense PDFS signal intensity.
Inflammatory changes with edema signal and mild muscle enlargement are seen within the distal thigh and periarticular musculature with hypointense T1 and hyperintense T2 and PDFS signal.
Normal both hip joints with no evidence of significant joint effusion or septic arthritis.
The findings are those of distal femoral osteomyelitis with subperiosteal abscess and inflammatory myositis of the distal thigh muscles.