Anatomy, Biomechanics & Pathophysiology of the Musculoskeletal System Flashcards

Which bone is classified as part of the axial skeleton?

Answer: Vertebra

The axial skeleton forms the central axis of the body and includes the skull, vertebral column (spine), and thoracic cage (ribs and sternum). Vertebrae are the individual bones that make up the vertebral column, providing support and protecting the spinal cord, thus classifying them as part of the axial skeleton.

What is the primary function of synovial fluid in joints?

Answer: Lubricates and nourishes joints

Synovial fluid is a viscous fluid found in the cavities of synovial joints. Its primary functions are to reduce friction between the articular cartilages during movement, acting as a lubricant, and to provide nutrients to the avascular articular cartilage, ensuring joint health and smooth motion.

Which type of muscle contraction results in no change in muscle length?

Answer: Isometric

An isometric contraction occurs when a muscle generates force without changing its length. This happens when the muscle attempts to move an immovable object or stabilize a joint, where the tension increases but the muscle fibers do not shorten or lengthen.

Which structure connects muscle to bone?

Answer: Tendon

Tendons are strong, fibrous connective tissues that serve as the attachment points between muscles and bones. They transmit the force generated by muscle contraction to the bones, enabling movement across joints.

Which condition is characterized by inflammation of a joint?

Answer: Arthritis

Arthritis is a general term that refers to inflammation of one or more joints. It encompasses over 100 different conditions, all characterized by symptoms such as joint pain, swelling, stiffness, and reduced range of motion, which are direct results of joint inflammation.

What type of joint allows the greatest range of motion?

Answer: Ball-and-socket joint

Ball-and-socket joints, such as the hip and shoulder, feature a rounded head of one bone fitting into a cup-like depression of another. This anatomical structure allows for movement in multiple planes, including flexion, extension, abduction, adduction, circumduction, and rotation, providing the greatest range of motion among all joint types.

Which part of the musculoskeletal system is affected by scoliosis?

Answer: Spine

Scoliosis is a medical condition characterized by an abnormal, sideways curvature of the spine. It can affect any part of the spine, leading to a C- or S-shaped curve, and is a primary concern for orthotics specialists who often manage it with bracing.

What is the main function of ligaments?

Answer: Connect bone to bone

Ligaments are tough, fibrous bands of connective tissue that primarily connect bones to other bones, forming joints. Their main function is to stabilize joints, limit excessive movement, and prevent dislocations, ensuring the structural integrity of the skeletal system.

What biomechanical principle explains why longer levers increase force at the joint?

Answer: Lever arm length principle

The lever arm length principle explains that a longer lever arm (the perpendicular distance from the axis of rotation to the line of force) increases the torque or rotational force generated. In biomechanics, this means that applying force further from a joint's axis of rotation creates a greater moment, effectively increasing the force or mechanical advantage at that joint. This principle is fundamental to understanding how orthoses and human movement leverage mechanical advantage.