Tubercular Osteomyelitis | NEET Based MCQ

Which of the following is NOT TRUE regarding tubercular osteomyelitis? 

A. It is a secondary TB 
B. Periosteal reaction is seen 
C. Sequestration is uncommon 
D. Inflammation is minimum

Answer. B, (Periosteal reaction is seen)

Tubercular osteomyelitis

• The spine is the commonest site of bone and joint tuberculosis, constituting about 50 percent of the total number of cases. The next in order of frequency are the hip, the knee and the elbow.

• Tubercular osteomyelitis more commonly affects the ends of the long bone, unlike pyogenic osteomyelitis which affects the metaphysis.

• Bone and joint tuberculosis is always secondary to some primary focus in the lungs, lymph nodes, etc. The mode of spread from the primary focus may be either hematogenous or by direct extension from a neighboring focus.

• Fibrous ankylosis is a common outcome of healed tuberculosis of the joints except in the spine where bony ankylosis follows more often.

• A tubercular osteomyelitis presents as a well-defined area of bone destruction, typically with minimal reactive new bone formation. This is unlike a pyogenic infection where reactive periosteal new bone formation is an important feature.

Tuberculosis may cause a chronic granulomatous osteomyelitis.

• The most often affected vertebrae are T10 – L1

• Initial X-Ray investigation may only reveal osteoporosis with narrowing of the disc space

• As the condition proceeds radiology shows bone destruction without the periosteal reaction so typical of pyogenic infection.
• In addition to narrowing of the disc space, collapse of the anterior portions of the vertebral bodies and sometimes the delineation of a clear paravertebral abscess.

• There is an increased erythrocyte sedimentation rate and a positive Mantoux test.

• Pure tuberculous osteomyelitis involving flat membranous bone like scapula is extremely rare.

• Characteristic features of acute bacterial infection (osteomyelitis)

— Periosteal reaction is characteristic

— Sequestrum is seen

— Involucrum is seen

— Abscess formation with signs of inflammation