Introduction Overview bone infarcts are often thought to be in the same spectrum of disease as osteonecrosis occurs within the metaphysis or diaphysis of long bone Epidemiology & Incidence similar risk factors as those seen in osteonecrosis trauma, sickle cell disease, connective tissue disorders, Gaucher's disease, steroid use Mechanism interruption of blood supply by intrinsic or extrinsic factors Presentation Symptoms usually asymptomatic often found when imaging the extremities for other reasons Imaging Radiographs medullary lesion of sheet-like central lucency surrounded by sclerosis with a serpiginous border "smoke up the chimney" MRI key feature is that central signal remains of normal marrow T1 weighted images peripheral low signal due to grannulation tissue and to lesser extent sclerosis periphery may enhance post gadolinium T2 weighted images acute infarct may show ill-defined non-specific area of high signal intense inner ring of granulation tissue and a hypointense outer ring of sclerosis Bone Scan cold in early phases hot in late resorptive and revascularisation phase Treatment Nonoperative observation indications usually asymptomatic and do not require treatment
QUESTIONS 1 of 1 1 Previous Next (OBQ08.167) A 45-year-old female twists her knee suddenly while playing tennis. She denies any history of knee pain in the past. Radiographs are shown in Figure A. What is the diagnosis? Review Topic QID: 553 FIGURES: A 1 Bone infarct 82% (1298/1592) 2 Osteonecrosis 2% (30/1592) 3 Metastatic carcinoma 1% (16/1592) 4 Osteosarcoma 0% (7/1592) 5 Enchondroma 15% (231/1592) Select Answer to see Preferred Response PREFERRED RESPONSE 1