A 55-year-old diabetic presents with a draining sinus over the right tibia for 2 years. X-ray shows sclerotic bone with a central lucency. Biopsy shows lamellar bone surrounding necrotic bone (sequestrum). The dead segment of necrotic cortical bone that has separated from the living bone is called:
- A Sequestrum ✓
- B Involucrum
- C Cloaca
- D Brodie's abscess
Explanation
A sequestrum is the avascular necrotic fragment of bone that has separated from the living bone in chronic osteomyelitis. It is maintained by bacteria and acts as a nidus for persistent infection. The involucrum is the new living bone shell formed by the periosteum around the sequestrum. Cloaca is the opening in the involucrum through which pus and sometimes pieces of sequestrum are discharged via sinuses. Brodie's abscess is a subacute form of osteomyelitis presenting as a loculated abscess cavity surrounded by sclerotic bone, usually metaphyseal, and typically due to low-virulence organisms.
Reference: Maheshwari Essential Orthopaedics, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.