The biomechanics of elbow extension

Thread starter thegoose
Start date Nov 25, 2023
Tags

Biomechanics Physics Sin

In summary, the biomechanics of elbow extension involves the coordinated movement of bones, muscles, and ligaments, primarily engaging the triceps brachii muscle to extend the forearm at the elbow joint. The elbow joint functions as a hinge joint, allowing for flexion and extension through the interaction of the humerus, radius, and ulna. Kinematic analysis reveals that elbow extension is influenced by factors such as muscle strength, joint angle, and loading conditions. Understanding these mechanics is crucial for rehabilitation and performance optimization in sports and daily activities.

Nov 25, 2023

thegoose

Homework Statement: I noticed that when I do a calculation of the form 85-90 it gives a result of -5, which affects my overall answer by giving a negative number. I think I didn't correctly determine the angle of my muscle strength. Would it be possible for this angle to be 0°? So, by doing the 85-0 calculation, we would get a positive number.

Relevant Equations: Σ𝐹⃗ = 0

X=

Σ𝐹𝑥 = 0

−𝐹𝑃𝑥 + 𝐹𝑀 sin (𝛽 − 90°) + 𝐹𝑒𝑙 sin (180 − 𝛽 − 𝜃) = 0

𝐹𝑃𝑥 = 𝐹𝑀 sin ( 𝛽 − 90°) +𝐹𝑒𝑙 sin(180 − 𝛽 − 𝜃)

𝐹𝑃𝑥 = 93.6650N sin (85 − 90) + 28.11N sin(180 − 85 − 79)

Fpx= -8.16344N +7.74816N

𝐹𝑃𝑥 = -0.4154 N←

Physics news on Phys.org

Nov 25, 2023

haruspex

Science Advisor

Homework Helper

Insights Author

Gold Member

Please define all your variables.
I assume FM means the force exerted by a muscle, but it seems to be exerted directly down at the shoulder pivot, which is not going to achieve anything. You need to analyse torques, not just forces, and consider the shoulder joint in more detail.

Last edited: Nov 25, 2023

FAQ: The biomechanics of elbow extension

What muscles are involved in elbow extension?

The primary muscle responsible for elbow extension is the triceps brachii, which is located on the back of the upper arm. Additionally, the anconeus muscle assists in the extension process.

How does the elbow joint structure facilitate extension?

The elbow joint is a hinge joint formed by the articulation of the humerus, ulna, and radius bones. The olecranon process of the ulna fits into the olecranon fossa of the humerus, allowing a stable and controlled extension movement.

What role do ligaments play in elbow extension?

Ligaments, such as the ulnar collateral ligament and the radial collateral ligament, provide stability to the elbow joint during extension. They prevent excessive sideways movement and ensure the joint moves in a controlled hinge-like manner.

How can elbow extension strength be measured?

Elbow extension strength can be measured using a dynamometer, which quantifies the force generated by the triceps brachii. Isokinetic testing machines can also assess the strength and endurance of the muscles involved in elbow extension.

What are common injuries associated with elbow extension?

Common injuries include triceps tendonitis, which is inflammation of the tendon attaching the triceps muscle to the elbow, and olecranon bursitis, which is inflammation of the bursa located at the tip of the elbow. Overuse and repetitive stress are typical causes of these injuries.