Answer for BIR CoW 05 May 2024
Perthe's disease
Findings
Asymmetric enlargement of bilateral femoral head and neck (coxa magna) Flattening of the femoral head (coxa plana) with contour irregularity. Incomplete coverage of the femoral head within the acetabulum with lateral protrusion of articular surface. Cortical break with collapse involving anterosuperior surface of right head of femur Linear subchondral hyperintensities in bilateral head of femur.
Discussion
Legg-Calvé-Perthes (LCPD) disease is a childhood hip disorder that results in infraction of the bony epiphysis of the femoral head. LCPD represents idiopathic avascular necrosis of the femoral head. The disease is bilateral in 10-20% of patients and usually affects children aged 4-8 years. Early radiographic signs of LCPD include small femoral epiphysis, sclerosis of the femoral head with sequestration and collapse, slight widening of the joint space caused by thickening of the cartilage, failure of epiphyseal growth, the presence of joint fluid, or joint laxity. Late signs of LCPD on radiographs include delayed osseous maturation of a mild degree, a radiolucent crescent line representing a subchondral fracture, femoral head fragmentation and femoral neck cysts from intramedullary hemorrhage or extension of physeal cartilage into metaphysis, loose bodies, coxa plana and coxa magna, or remodeling of the femoral head, which becomes wider and flatter, similar in appearance to a mushroom. MRI : Early in the course of Legg-Calve-Perthes disease, irregular foci of low signal intensity or linear segments replace the normal high signal intensity of bone marrow in the femoral epiphysis on T1- and T2-weighted images. Other findings include an intra-articular effusion and a small, laterally displaced ossification nucleus, labral inversion, and femoral head deformity. On STIR images, influx of fluid into areas of articular cartilage irregularity is seen. The asterisk sign is defined as findings of areas of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images in marrow. The double-line sign occurs in as many as 80% of patients and represents the sclerotic rim, which appears as a signal void. This sign is demonstrated as a line between necrotic and viable bone edges, with a hyperintense rim of granulation tissue.
Findings
Asymmetric enlargement of bilateral femoral head and neck (coxa magna) Flattening of the femoral head (coxa plana) with contour irregularity. Incomplete coverage of the femoral head within the acetabulum with lateral protrusion of articular surface. Cortical break with collapse involving anterosuperior surface of right head of femur Linear subchondral hyperintensities in bilateral head of femur.
Discussion
Legg-Calvé-Perthes (LCPD) disease is a childhood hip disorder that results in infraction of the bony epiphysis of the femoral head. LCPD represents idiopathic avascular necrosis of the femoral head. The disease is bilateral in 10-20% of patients and usually affects children aged 4-8 years. Early radiographic signs of LCPD include small femoral epiphysis, sclerosis of the femoral head with sequestration and collapse, slight widening of the joint space caused by thickening of the cartilage, failure of epiphyseal growth, the presence of joint fluid, or joint laxity. Late signs of LCPD on radiographs include delayed osseous maturation of a mild degree, a radiolucent crescent line representing a subchondral fracture, femoral head fragmentation and femoral neck cysts from intramedullary hemorrhage or extension of physeal cartilage into metaphysis, loose bodies, coxa plana and coxa magna, or remodeling of the femoral head, which becomes wider and flatter, similar in appearance to a mushroom. MRI : Early in the course of Legg-Calve-Perthes disease, irregular foci of low signal intensity or linear segments replace the normal high signal intensity of bone marrow in the femoral epiphysis on T1- and T2-weighted images. Other findings include an intra-articular effusion and a small, laterally displaced ossification nucleus, labral inversion, and femoral head deformity. On STIR images, influx of fluid into areas of articular cartilage irregularity is seen. The asterisk sign is defined as findings of areas of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images in marrow. The double-line sign occurs in as many as 80% of patients and represents the sclerotic rim, which appears as a signal void. This sign is demonstrated as a line between necrotic and viable bone edges, with a hyperintense rim of granulation tissue.
Note:
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!
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!