This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Ring sequestrum is seen in 
Select and explain. 
A. Typhoid osteomyelitis, B. Chronic osteomyelitis, C. Amputation stump, D. Tuberculosis osteomyelitis
C: Amputation stump
Answer: C: Amputation stump 
Explanation: C i.e. Amputation Stump Excessive periosteal stripping is contraindicated as it may result in formation of ring sequestrum in amputation stumpQType of Sequestrum Found InRing sequestrum - Amputation stumpsQ - Around pin tracks (external fixator)Tubular sequestrum - Hematogenous osteomyelitis - Segmental fractures (middle segment)Rice grain sequestrum - Tuberculosis