**Question:** All of the following are characteristics of rickets except?

A. Increased bone flexibility
B. Enlarged bones
C. Normal growth velocity
D. Hypocalcemic tetany

**Core Concept:**
Rickets is a skeletal disorder primarily affecting children, resulting from impaired calcium and vitamin D absorption. It leads to softening of bones (osteomalacia) and can cause deformities, growth retardation, and pain.

**Why the Correct Answer is Right:**
C. Normal growth velocity is not a characteristic of rickets because the disease typically results in growth retardation due to impaired bone mineralization.

**Why Each Wrong Option is Incorrect:**
A. Increased bone flexibility might be present in mild cases, but it is not a defining characteristic of rickets.
B. Enlarged bones is not a typical feature of rickets and can be more associated with conditions like osteoporosis.
D. Hypocalcemic tetany is a condition characterized by muscle spasms due to low calcium levels. Although rickets can lead to hypocalcemia, the specific condition of hypocalcemic tetany is not directly associated with rickets.

**Clinical Pearl / High-Yield Fact:**
Hypocalcemic tetany is more closely related to conditions like hypoparathyroidism, where low calcium levels lead to tetany. In rickets, hypocalcemia is secondary to impaired calcium absorption and is usually not severe enough to cause tetany.

**Correct Answer:**
D. Hypocalcemic tetany

Explanation: While hypocalcemic tetany is a clinical manifestation of low calcium levels, it is not specific to rickets. Rickets primarily causes hypocalcemia due to impaired calcium absorption and may not result in tetany due to milder hypocalcemia.