UPPER ARM

GENERAL INFORMATION

The upper arm muscles are crucial for arm movement, providing both flexion and extension at the elbow and shoulder joints. Upper arm muscles are responsible for actions like lifting, pushing, and pulling, making them essential for daily activities and athletic performance. The primary muscles in the upper arm include the biceps brachii, triceps brachii, brachialis, and coracobrachialis, all of which contribute to arm strength, stability, and mobility.

ORIGIN OF UPPER ARM

• Biceps Brachii: Long head from the supraglenoid tubercle of the scapula; short head from the coracoid process of the scapula.

• Triceps Brachii: Long head from the infraglenoid tubercle of the scapula; lateral and medial heads from the posterior surface of the humerus.

• Brachialis: Distal half of the anterior surface of the humerus.

• Coracobrachialis: Coracoid process of the scapula.

INSERTION POINT

• Biceps Brachii: Radial tuberosity and bicipital aponeurosis.

• Triceps Brachii: Olecranon process of the ulna.

• Brachialis: Coronoid process and tuberosity of the ulna.

• Coracobrachialis: Medial surface of the humerus shaft.

MAJOR ARTERIES

• Brachial Artery: The primary artery supplies blood to the upper arm muscles.

• Deep Brachial Artery (Profunda Brachii): Supplies the triceps brachii.

• Radial and Ulnar Arteries: Provide blood flow to the forearm but also supply the lower parts of the biceps and triceps.

NEURAL INNERVATION

• Biceps Brachii: Musculocutaneous nerve (C5-C6).

• Triceps Brachii: Radial nerve (C6-C8).

• Brachialis: Musculocutaneous nerve (C5-C6), with some innervation from the radial nerve.

• Coracobrachialis: Musculocutaneous nerve (C5-C7).

TRIGGER POINT

Trigger points in the upper arm muscles, especially the biceps and triceps, can cause referred pain in the shoulder, elbow, and even the wrist. These points often develop from repetitive lifting, improper arm mechanics, or overuse, leading to muscle tightness, soreness, and restricted arm movement.

CONCENTRIC FUNCTION

• Biceps Brachii: Flexes the elbow and supinates the forearm, essential for lifting and pulling movements.

• Triceps Brachii: Extends the elbow, which is crucial for pushing movements and straightening the arm.

• Brachialis: Strongly flexes the elbow, providing primary strength during elbow flexion.

• Coracobrachialis: Flexes and adducts the arm at the shoulder, stabilising the humerus during arm movements.

ECCENTRIC FUNCTION

• Biceps Brachii: Controls elbow extension, helping to lower objects smoothly after lifting.

• Triceps Brachii: Regulates elbow flexion, slowing the arm as it returns from an extended position.

• Brachialis: Helps control elbow extension by resisting downward motion.

• Coracobrachialis: Controls arm abduction and extension, maintaining stability during shoulder movements.

ISOMETRIC FUNCTION

Upper arm muscles stabilise the elbow and shoulder during static activities, such as holding a weight in place or maintaining arm position during pushing or pulling. The biceps brachii and triceps brachii work together to provide balance and tension during isometric contractions, preventing excessive movement of the arm.

RELATED MUSCLE – SCIENTIFIC NAMES

• Deltoid: Assists with shoulder abduction and stabilises the arm during overhead movements.

• Brachioradialis: Aids in elbow flexion and stabilises the forearm.

• Pectoralis Major: Contributes to shoulder flexion and adduction.

• Latissimus Dorsi: Works with the triceps to extend the arm at the shoulder.

• Teres Major: Assists in shoulder adduction and internal rotation.

ANTAGONIST

• Triceps Brachii: Opposes the biceps brachii by extending the elbow while the biceps flexes it.

• Biceps Brachii: Works against the triceps during elbow flexion.

• Latissimus Dorsi: Opposes the coracobrachialis in shoulder flexion, helping extend the shoulder.

• Brachioradialis: Assists in elbow flexion, opposing the extension provided by the triceps.

• Deltoid (posterior fibres): Opposes shoulder flexion performed by the coracobrachialis.

COMMON INJURIES

• Biceps Tendonitis: Inflammation of the biceps tendon, often caused by overuse, resulting in pain and discomfort during elbow or shoulder movement.

• Triceps Strain: Overstretching or tearing of the triceps muscle, typically from sudden forceful movements, leading to pain and limited elbow extension.

• Brachialis Strain: Overuse or injury to the brachialis, causing pain during elbow flexion, particularly in heavy lifting or repetitive actions.

• Bicep Tear: A partial or complete tear of the bicep tendon, causing pain, bruising, and weakness in the upper arm. That often requiring surgical intervention.

• Coracobrachialis Strain: Injury to the coracobrachialis muscle from overuse or poor mechanics, leading to shoulder pain and restricted arm mobility.

EXERCISES FOR UPPER ARM

• Bicep Curls: Hold a dumbbell in each hand, curl the weights towards your shoulders, engaging the biceps to strengthen elbow flexion.

• Tricep Dips: Use parallel bars or a bench to lower and raise your body, targeting the triceps to improve arm extension strength.

• Hammer Curls: Hold dumbbells in a neutral grip and curl them towards your shoulders, engaging the brachialis and improving overall arm strength.

• Overhead Tricep Extensions: Hold a dumbbell overhead with both hands, lower it behind your head, and extend your arms to target the triceps brachii.

• Push-Ups: Engage the triceps and upper arm muscles by lowering and lifting your body in a controlled manner, improving upper body strength and stability.

STRETCHES FOR UPPER ARM

• Bicep Stretch: Extend your arm behind you and press the palm against a wall, stretching the biceps and improving arm flexibility.

• Tricep Overhead Stretch: Reach one arm overhead and bend the elbow, using the opposite hand to gently push the elbow back, stretching the triceps.

• Doorway Chest Stretch: Stand in a doorway with your arm extended at shoulder height and gently lean forward to stretch the coracobrachialis and pectorals.

• Cross-Body Arm Stretch: Pull one arm across your chest with the opposite hand to stretch the posterior deltoid and upper arm muscles.

• Wrist Flexor Stretch: Extend your arm forward, palm up, and gently pull back on the fingers to stretch the brachialis and biceps brachii.