Question 1

A patient is unable to smile on one side of their face after a minor stroke. Which muscle is most likely affected, and what is its primary action?

Accepted Answer

Zygomaticus major; draws angle of mouth superiorly and laterally

Question 2

During a physical exam, a patient is asked to close their eyes tightly. Which muscle is primarily responsible for this action?

Accepted Answer

Orbicularis oculi

Question 3

A dentist notices that a patient has difficulty elevating their mandible to close their mouth. Which muscle is most likely impaired?

Accepted Answer

Masseter

Question 4

Which muscle, when contracted, causes the thoracic cavity to increase in size, resulting in inhalation?

Accepted Answer

Diaphragm

Question 5

A weightlifter is performing a deadlift and needs to maintain an erect posture of the vertebral column. Which group of muscles is primarily responsible for this action?

Accepted Answer

Erector spinae

Question 6

A patient presents with difficulty abducting their arm at the shoulder joint. Which muscle is most likely compromised?

Accepted Answer

Deltoid

Question 7

Which muscle is responsible for flexing the forearm and is commonly used when performing a biceps curl?

Accepted Answer

Biceps brachii

Question 8

A runner experiences pain when flexing their thigh at the hip joint. Which muscle is most likely involved?

Accepted Answer

Iliopsoas (Psoas major and Iliacus)

Question 9

Which muscle group is primarily responsible for extending the leg at the knee joint, such as when kicking a ball?

Accepted Answer

Quadriceps femoris

Question 10

A patient is unable to plantar flex their foot, making it difficult to stand on tiptoe. Which muscle is most likely affected?

Accepted Answer

Gastrocnemius

Question 11

Which muscle acts as a fixator of the scapula and is essential for stabilizing the shoulder during arm movements?

Accepted Answer

Trapezius

Question 12

A violinist develops pain from repetitive wrist flexion and ulnar deviation. Which muscle is most likely overused?

Accepted Answer

Flexor carpi ulnaris

Question 13

Which muscle is responsible for compressing the abdomen and is engaged during forced expiration, such as blowing up a balloon?

Accepted Answer

Transversus abdominis

Question 14

A patient is unable to retract their mandible. Which muscle is most likely not functioning properly?

Accepted Answer

Temporalis

Question 15

Which muscle is primarily responsible for laterally rotating the arm at the shoulder joint?

Accepted Answer

Infraspinatus

Question 16

A soccer player injures their hamstrings. Which of the following muscles is NOT part of the hamstring group?

Accepted Answer

Rectus femoris

Question 17

Which muscle is responsible for pronating the forearm, such as when turning a doorknob counterclockwise with the right hand?

Accepted Answer

Pronator teres

Question 18

A patient is unable to abduct their thigh at the hip joint. Which muscle is most likely affected?

Accepted Answer

Gluteus medius

Question 19

During inhalation, which two muscles contract to increase the size of the thoracic cavity?

Accepted Answer

Diaphragm and external intercostals

Question 20

A patient is unable to dorsiflex their foot, causing their toes to drag while walking. Which muscle is most likely impaired?

Accepted Answer

Tibialis anterior

Major Skeletal Muscles and Their Actions: A Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard