Answer for BIR CoW 25 Jan 2026
Avascular necrosis of humerus
Findings
Flattening and collapse of humeral epiphysis with cortical erosion noted. Well demarcated serpiginous intramedullary T1/T2 heterointense areas noted in epiphysis, metaphysis and diaphysis of humerus. PD/STIR intrasubstance hyperintensity noted in myocutaneous junction of supraspinatus tendon. -Features suggestive of avascular necrosis of humerus with bone infarct
Discussion
Patient is a known case of sickle cell disease. Osteonecrosis of the humeral head, is considered the second most common location for osteonecrosis (following the femoral head). It generally develops in the subchondral region. Causes: trauma, sickle cell anemia, SLE, Gaucher’s disease, corticosteroid therapy, iatrogenic. The most common initial site is the upper middle portion of the humeral head. Xrays: Snowcap sign: Dense sclerosis on the humeral head in osteonecrosis is called the in radiographs. Crescent sign: classic diagnostic feature that demonstrates subchondral collapse. This may progress to depression of the articular surface with subsequent arthritic changes. MRI: Double line sign On T2 sequences-inner bright line from granulation tissue and outer dark line from sclerotic bone. The Cruess classification of humeral head osteonecrosis uses plain radiographs, CT and/or MRI for its staging system. The Cruess classification is composed of five stages: stage I: pre-radiological stage with normal radiographs but CT or MRI osseous changes present stage II: osteoporosis, sclerosis, or both, or localized subchondral osteolysis without fracturing stage III: subchondral fracture with mild loss of congruity and a “crescent sign” stage IV: extensive collapse of subchondral bone with severe articular incongruity and secondary degenerative changes (osteochondral flaps may break free and become loose bodies)
Reference:
Essentials of Skeletal Radiology , yochum and rowe ;3rd Edition. Imaging of musculoskeletal manifestations in sickle cell disease patients. AJR, 2017 Clinical review of osteonecrosis of humeral head in sickle cell haemoglobinopathy. Lonergan GJ, Cline DB, Abbondanzo SL. Sickle cell anemia. Radiographics.
Findings
Flattening and collapse of humeral epiphysis with cortical erosion noted. Well demarcated serpiginous intramedullary T1/T2 heterointense areas noted in epiphysis, metaphysis and diaphysis of humerus. PD/STIR intrasubstance hyperintensity noted in myocutaneous junction of supraspinatus tendon. -Features suggestive of avascular necrosis of humerus with bone infarct
Discussion
Patient is a known case of sickle cell disease. Osteonecrosis of the humeral head, is considered the second most common location for osteonecrosis (following the femoral head). It generally develops in the subchondral region. Causes: trauma, sickle cell anemia, SLE, Gaucher’s disease, corticosteroid therapy, iatrogenic. The most common initial site is the upper middle portion of the humeral head. Xrays: Snowcap sign: Dense sclerosis on the humeral head in osteonecrosis is called the in radiographs. Crescent sign: classic diagnostic feature that demonstrates subchondral collapse. This may progress to depression of the articular surface with subsequent arthritic changes. MRI: Double line sign On T2 sequences-inner bright line from granulation tissue and outer dark line from sclerotic bone. The Cruess classification of humeral head osteonecrosis uses plain radiographs, CT and/or MRI for its staging system. The Cruess classification is composed of five stages: stage I: pre-radiological stage with normal radiographs but CT or MRI osseous changes present stage II: osteoporosis, sclerosis, or both, or localized subchondral osteolysis without fracturing stage III: subchondral fracture with mild loss of congruity and a “crescent sign” stage IV: extensive collapse of subchondral bone with severe articular incongruity and secondary degenerative changes (osteochondral flaps may break free and become loose bodies)
Reference:
Essentials of Skeletal Radiology , yochum and rowe ;3rd Edition. Imaging of musculoskeletal manifestations in sickle cell disease patients. AJR, 2017 Clinical review of osteonecrosis of humeral head in sickle cell haemoglobinopathy. Lonergan GJ, Cline DB, Abbondanzo SL. Sickle cell anemia. Radiographics.
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
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Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!