Secondary detion of the eye is an example of the following law
**Core Concept**
The secondary deviation of the eye refers to the excessive outward turning of the eye in abduction, which is a characteristic feature of sixth nerve palsy. This phenomenon occurs due to the inability of the medial rectus muscle to function properly.
**Why the Correct Answer is Right**
The correct answer is related to the **Hering's Law of Equal Innervation**. According to this law, when a muscle is paralyzed, the innervation to the muscles of the opposite action is also reduced. In the case of sixth nerve palsy, the medial rectus muscle is paralyzed, leading to a reduction in the innervation to the lateral rectus muscle. This results in an excessive outward turning of the eye in abduction, also known as secondary deviation.
**Why Each Wrong Option is Incorrect**
* **Option A:** There is no direct relationship between secondary deviation and **Bell's Law**. Bell's Law states that paralysis of a muscle results in increased innervation to the antagonist muscle, which is opposite of what happens in sixth nerve palsy.
* **Option B:** The **Sherrington's Law of reciprocal innervation** states that when a muscle is contracted, the antagonist muscle is inhibited. This law is not directly related to secondary deviation.
* **Option D:** The **Law of reciprocal innervation** is a broader concept that encompasses the relationship between agonist and antagonist muscles. However, it does not specifically explain the phenomenon of secondary deviation.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the Hering's Law of Equal Innervation is a key concept in understanding the effects of muscle paralysis on the nervous system. This law can be remembered using the mnemonic "H.E.A.R." - Hering's Equal Action Rule.
**Correct Answer: C. Hering's Law of Equal Innervation**