D. None of the above answers are correct.

Joint Structure and Function 6th Edition Levangie Test Bank

Chapter 1: Biomechanical Applications to Joint Structure and Function

Multiple Choice

• When you raise a cup to your mouth, a of motion occurs at the elbow

joint.

• rotation only
• translation only
• translation and rotation
• None of the above answers are correct.

ANS: C

Rationale: Rotatory and translatory motions in the human body most commonly occur together.

• Hip abduction from an anatomic position would occur in which plane?
• Sagittal
• Frontal
• Transverse
• Horizontal

ANS: B

Rationale: The frontal (coronal) plane divides the body into front and back halves. Movements in this plane occur side to side, such as the case in abduction of the hip.

• Which of the following describes the phenomenon that when two forces come in contact, the

second force will respond to the contact by the first force with equal magnitude and in the opposite direction?

• Law of Inertia
• Law of Reaction
• Law of Acceleration
• None of the above answers are correct.

ANS: B

• A class lever is described by the fulcrum occurring at one end,

followed by the resistance (load or weight) and then the force (effort). 1 / 4

• First
• Second
• Third
• Fourth

ANS: B

• In what type of lever is the Mechanical Advantage always less than one?
• First
• Second
• Third
• Fourth

ANS: C

Rationale: A mechanical advantage less than one occurs when the effort moment arm is shorter than the resistance moment arm. This is always the case in a third-class level if all forces are equal.

• Which of the following best describes torque?
• The force a muscle generates
• A force times the perpendicular distance from the line of force to the axis of rotation
• A force times the distance measured along the lever from the line of force to the axis of

rotation

• The distance a muscle can move

ANS: B

Rationale: Torque equals force times the distance of the force to the axis. The distance must be represented by the moment arm of the force, not just the direct distance as measured up the lever.The moment arm is the perpendicular distance of the line of the force from the axis of rotation.

NARRBEGIN: Figure 1-7 2 / 4

NARREND

• In Figure 1-7, the biceps is acting on the forearm. What is the force of the biceps, FB, given

the following: moment arm of the biceps, d = 0.02 m and torque due to the biceps, TM = –5 Nm?

A. –0.1 N

B. 1,250 N

C. 5 N

D. –250 N

ANS: D

Rationale: Because T = (F) (MA) therefore, F= T/MA: (–)5 Nm/0.02 m = (–)250 N. The negative sign is used to show direction of the force. Due to the small moment arm, the force necessary to produce (–)5 Nm of torque is quite large.

NAR: Figure 1-7

• As your patient abducts her shoulder from 90° to 120°, the moment arm of the muscle

decreases. If the torque from the deltoid remains constant, the force of the deltoid would as the shoulder is abducted.

• remain the same
• increase
• decrease
• become 0 N

ANS: B

Rationale: If the torque were to remain the same, the force would have to increase as the muscle’s moment arm decreases. Force and moment arm have an inverse relationship if torque is to remain constant. 3 / 4

NARRBEGIN: Figure 1-9

A

NARREND

B C D

• In Figure 1-9, at which position does the weight have the greatest torque capabilities on the

knee joint?

• A
• B
• C
• D

ANS: D

Rationale: The force of the weight did not change from position to position; therefore, position D would have the greatest torque capabilities due to this position offering the largest moment arm of the weight on the lever.

NAR: Figure 1-9

• In Figure 1-9, at which position does the weight produce the greatest distractive force on the

knee joint?

• A
• B
• C
• D

ANS: A

Rationale: When the line of force is parallel with the moving segment, it will create either a distractive or compressive force between the two bony segments. Distraction occurs when there is a pull or movement of one bony segment away from another. Because the weight would be moving the tibia away from the femur, it will create a distractive force.

NAR: Figure 1-9

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