When amount of load increases to TMJ then amount of which of the following zone increases:
**Core Concept**
The Temporomandibular Joint (TMJ) is a complex synovial joint that allows for the movement of the mandible. When the amount of load increases on the TMJ, it triggers a series of physiological responses to maintain joint homeostasis. The TMJ has a unique structure that includes an articular disc, ligaments, and muscles that work together to distribute the load and maintain joint stability.
**Why the Correct Answer is Right**
When the amount of load increases on the TMJ, the articular disc becomes thicker to increase its surface area and distribute the load more evenly. This is achieved through the compression of the disc's fibrocartilaginous tissue, which allows it to absorb the increased load and maintain joint stability. The articular disc's thickness increases to accommodate the increased load, thereby reducing the pressure on the joint surfaces and preventing damage.
**Why Each Wrong Option is Incorrect**
* **Option A:** The synovial fluid does not directly increase in response to increased load on the TMJ. While synovial fluid does play a role in joint lubrication and nutrition, its quantity is not directly related to the load on the joint.
* **Option B:** The TMJ ligaments do not increase in size or thickness in response to increased load. Instead, they provide stability and support to the joint by connecting the bones and articular disc.
* **Option D:** The muscles of mastication do not increase in size or activity in response to increased load on the TMJ. While they do play a role in joint movement and stabilization, their activity is not directly related to the load on the joint.
**Clinical Pearl / High-Yield Fact**
The TMJ's articular disc plays a crucial role in maintaining joint homeostasis and preventing damage from increased load. Understanding the disc's response to increased load is essential for diagnosing and managing TMJ disorders.
**Correct Answer:** C.