MSK cases for discussion Dr. Abdelaty Shawky Dr. Gehan Mohamed

Case 1 A 9-year-old boy complains of 2 weeks of pain in the hip. His temperature is 38.9°C. Laboratory studies show an elevated erythrocyte sedimentation rate. An X-ray reveals a mottled radiolucent defect in the upper femur, with abundant periosteal new bone formation.

Fine-needle aspiration shows numerous neutrophils and cocci. Staphylococcus aureus is cultured from the bone lesion. A biopsy shows a fragment of necrotic bone embedded in fibrinopurulent exudate.

M/E Dense neutrophilic infiltrate and necrotic bone

M/E Inflammatory infiltrate surrounding a necrotic bone fragment

Now answer Your diagnosis of the case is…. Most common site of affection is….. Why?? Necrotic bone is called……. Subperiosteal new bone formation is called…. And openings through which pus is discharged are called…..

Case 2 A 10-year-old boy complains of pain and swelling around his right knee of 3 weeks' duration that has not improved with rest. His mother denies a history of trauma to the knee. A radiograph shows a destructive mass arising from the metaphysis of the distal femur

RADIOLOGY l Plain radiograph shows an ill-defined destructive tumor in the distal femur. Sun ray appearance Codman’s triangle

Grossly Irregular mass occupying the medullary part of metaphysis destroying the cortex. Grayish white, with areas of hemorrhage.

Microscopic examination

Malignant spindle-shaped cells laying down osteoid matrix

Now answer… Your diagnosis of the case is…… Most common site and age of the tumor is…… Spread of this tumor is by….. and prognosis is….

Case 3 A 65-year-old man complains of pain in his back, fatigue An X-ray examination reveals numerous lytic lesions in the lumbar vertebral bodies. Laboratory studies disclose mild anemia, and thrombocytopenia. Urinalysis shows 4+ proteinuria. A bone marrow biopsy discloses foci of abnormal plasma cell proliferation.

Radiology, Gross Multiple osteolytic lesions in the skull, vertebrae and pelvic bones

M/E Plasma cells with different grades of differentiation

Now What is your diagnosis of the case?