MMT Nerve Innervation and Muscle Function 1

Question 1

Which nerve innervates the deltoid muscle, making it the primary nerve tested during shoulder abduction MMT?

Accepted Answer

Axillary nerve

Answer

The axillary nerve (C5-C6) innervates the deltoid muscle, which is the primary mover tested during shoulder abduction in MMT.

Question 2

The biceps brachii, tested during elbow flexion MMT, is primarily innervated by which nerve?

Accepted Answer

Musculocutaneous nerve

Answer

The musculocutaneous nerve (C5-C6) innervates the biceps brachii, which performs elbow flexion and forearm supination.

Question 3

In MMT, weakness of the wrist extensors most directly implicates which peripheral nerve?

Accepted Answer

Radial nerve

Answer

The radial nerve (C6-C8) innervates the wrist extensors; complete radial nerve injury produces wrist drop.

Question 4

Which nerve innervates the gluteus medius, the primary muscle tested during hip abduction MMT?

Accepted Answer

Superior gluteal nerve

Answer

The superior gluteal nerve (L4-S1) innervates the gluteus medius and minimus, which are the primary hip abductors tested in MMT.

Question 5

Ankle plantarflexion weakness during MMT most directly implicates which nerve root level?

Accepted Answer

S1

Answer

Ankle plantarflexion (gastrocnemius/soleus) is primarily innervated at S1-S2, making S1 the key root level implicated by plantarflexion weakness.

(MMT) Manual Muscle Testing Practice Test