Answer:
Q1 : c. Polyostotic fibrous dysplasia
Q2 : b. Mazabraud syndrome.
Explanation:
Fibrous dysplasia is relatively uncommon bony disorder where the normal bone is replaced by scar like-fibrous tissue, causing progressive weakening of bone, deformities, limb shortening due to early closure of growth plate and fractures. It can involve single bone (mono-ostotic) or multiple bones (Polyostotic). Classical x-ray feature are presence of ground glass matrix with bony expansion, thinned out cortex. Common sites of involvement include craniofacial bones but sites are not uncommon. When the femur is involved, it produces deformity at the femoral neck causing coxa vara angulation at the hip. This is called Shepherd’s Crooks deformity. The bone scan shows diffuse/ heterogeneous increased tracer uptake in affected bones.
The bone scan findings may overlap with Polyostotic Paget’s disease of bone. However the age of presentation, clinical features and x ray can help to differentiate both entities. In Paget’s disease, x ray shows osteolytic/ (lucent) areas, subsequently appearing as coarsened trabeculae and bony enlargement and sclerotic changes with further progression.
Osteogenesis imperfecta is a genetic disorder which can range from milder form to very severe form, mostly presents very early in life. May be associated with other collagenous pathologies like blue sclera and hearing loss.
Q.2
Mazabraud syndrome is a rare syndrome where Polyostotic fibrous dysplasia is associated with intramuscular mxyoma.
In McCune-Albright syndrome, usually seen in girl child, Polyostotic fibrous dysplasia are associated with cafè-au-lait skin pigmentations, endocrine problems like diabetes, precocious puberty, goitre and firoadenomas of breast.
Osteogenesis imperfecta tarda is also known as Ekman-Lobstein disease.
Jaffe-Lichtenstein Syndrome is a broder term for syndromes associated with fibrous dysplasia.
References:
1. Yevgeniya S. Kushchayeva, Sergiy V. Kushchayev, Tetiana Y. Glushko, Sri Harsha Tella, Oleg M. Teytelboym, Michael T. Collins, Alison M. Boyce. Fibrous dysplasia for radiologists: beyond ground glass bone matrix. (2018) Insights into Imaging. 9 (6): 1035.
2. Zhibin Y, Quanyong L, Libo C, et al. The role of radionuclide bone scintigraphy in fibrous dysplasia of bone. Clin Nucl Med. 2004;29(3):177‐180.
3. https://radiopaedia.org/articles/fibrous-dysplasia.