**Question:** The most common sequelae of tuberculous spondylitis in an adolescent is

A. Scoliosis
B. Kyphosis
C. Cauda equina syndrome
D. Sternal or costal involvement

**Correct Answer:**

**Core Concept:** Tuberculous spondylitis, also known as tuberculous vertebral osteomyelitis, is a complication of Mycobacterium tuberculosis infection primarily affecting the spine. The infection leads to inflammation, destruction of vertebral bodies, and potential spinal deformities.

**Why the Correct Answer is Right:**

In adolescents, the most common consequence of tuberculous spondylitis is the development of kyphosis (rounded spine) due to vertebral collapse and destruction caused by the infection. This is more common than scoliosis (sideways curvature), cauda equina syndrome (compression of the spinal cord's posterior structures), or sternal or costal involvement (uncommon and often associated with disseminated disease).

**Why Each Wrong Option is Incorrect:**

A. Scoliosis (sideways curvature) is less common than kyphosis in tuberculous spondylitis sequelae. In adolescents, the spine is more flexible and can compensate for the kyphotic deformity. Scoliosis occurs in more mature individuals when the spine is less flexible.

B. Cauda equina syndrome (compression of the spinal cord's posterior structures) is less common than kyphosis in tuberculous spondylitis sequelae. Cauda equina syndrome usually occurs when there is significant compression of the spinal cord's posterior structures, which is less frequent in cases of vertebral body destruction.

C. Sternal or costal involvement is less common than vertebral involvement in tuberculous spondylitis. Tuberculosis usually affects the spine first, and sternal or costal involvement is uncommon unless the infection is disseminated (spread beyond the spine).

**Clinical Pearl:** A thorough understanding of the clinical manifestations of tuberculosis is essential for early diagnosis and initiation of appropriate treatment to prevent permanent spinal deformities and neurological deficits. In adolescents, kyphosis is more likely to occur due to the spine's flexibility and limited compensatory mechanisms compared to older individuals.