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By August 28, 2022Medical Animation

Left Shoulder Shoulder Anatomy

left shoulder shoulder anatomy

There are several key components to the left shoulder in left shoulder shoulder anatomy. The rotator cuff is one of them. These muscles provide stability and facilitate movement. The remaining muscles surround the joint space. Here, you’ll learn about the rotator cuff and the rest of the shoulder joint. You’ll also learn about the coraco-clavicular ligaments.


The movement of the arm in adduction and flexion is the opposite of shoulder abduction. This motion brings the arm closer to the center of the body. To perform shoulder adduction, the arm should be extended straight out in front of the body. When the arm is straight out in front of the body, the hand should be aligned with the shoulder.

Abduction of the left shoulder occurs when the arm is raised away from the middle of the body. Its normal range is about 30 to 50 degrees. The range varies from person to person depending on body composition and muscular build. A person with a muscular chest or biceps may have difficulty moving the arm inward. In such cases, turn the palms toward the body while bending the elbows.

The first part of abduction is carried out by the supraspinatus muscle, which is easily visible during an examination. This muscle articulates with the acromion to form a “U” shape. As a result, a person with shoulder arthritis has a decreased range of motion.

In contrast, ordinary surgeons believe that the arm may continue to be abducted. These surgeons term this motion flexion. However, both types of anatomists agree that the arms of a scarecrow are abducted. This is true no matter how much rotation the humerus undergoes or the plane at which it reaches the shoulder joint.

Internal Rotation

The internal rotation of the left shoulder is a basic movement of the arm. It is performed through a combination of internal and external movements. This type of motion helps to develop a range of motion in the shoulder and arms. In some cases, internal rotation can help to treat shoulder pain. However, you must understand that this movement is different from external rotation.

When performing internal rotation of the left shoulder, be sure to use the correct form. It is easy to overextend the shoulder, which puts too much stress on the tissues. To avoid this, avoid aggressively cranking or rolling your hand towards the ground. This can cause more damage in the future.

The subscapularis is a muscle found in the shoulder. This muscle is a part of the rotator cuff, the group of muscles that support and stabilize the shoulder joint. This muscle works to rotate the humerus inwards toward the body. It works with other muscles in the shoulder, including the pectoralis major, teres major, and anterior deltoid.

The range of shoulder movement is important in diagnosing shoulder pain and determining functional limitations. There are six normal movements of the shoulder. These movements help us carry out various activities of daily living. For example, we need to be able to reach high shelves and wash our hair. The range of movement of the shoulder is significantly influenced by the presence of diabetes.

To perform an internal rotation of the left shoulder, have your arm extended with the elbow at a 90-degree angle. Ensure that your fingers are parallel to the ground. The hand will point away from the back of your shoulder. If the hand cannot be separated from the back, this is a sign of a subscapularis tendon tear.

Rotator Cuff Tendons

Rotator cuff tendons are responsible for the movement of the shoulder. If these tendons become damaged, they can cause severe pain. Most injuries to the rotator cuff are caused by too much force. This can happen when you catch something that falls on your shoulder or lifts something heavy with your arm. In addition to this, rotator cuff injuries can also occur suddenly, such as when you fall onto your shoulder. Fortunately, a torn rotator cuff can be treated with physical therapy, but sometimes a surgical procedure is necessary.

Symptoms of a rotator cuff tear include pain and weakness in the muscle-tendon unit. The intensity of the pain depends on the extent of the tear. A partial tear may cause a lot of pain, while a complete tear may only cause moderate pain. A physician can help you determine if you have a torn rotator cuff and recommend a treatment plan.

Inflammation and pain in the rotator cuff can be caused by bursitis or rotator cuff injury. The subacromial bursa is the most common area for bursitis. It is also the most likely area for impingement. The subacromial space is extremely small, and the rotator cuff tendons often move very rapidly within this small space.

Conservative treatment options for a rotator cuff tear include resting the shoulder and avoiding activities that cause pain. Ice packs and ibuprofen can relieve pain and inflammation. In some cases, physical therapy can help strengthen shoulder muscles and prevent further damage.

Coraco-Clavicular Ligaments

The coracoclavicular ligaments of the left shoulder are composed of two bundles: the superior and the inferior bundle. The superior bundle originates at the superior aspect of the clavicle, while the inferior bundle is located at the lower portion of the clavicle. These two ligaments provide stability to the acromioclavicular joint, acting as the last brake in the presence of cranial tractions.

The coracoclavicular ligaments are two bands of fibrous connective tissue that connect the scapula to the clavicle. They serve to stabilize the shoulder, helping to prevent impingement syndrome. These ligaments are often thick and can contribute to impingement syndrome.

The ACCL and the MCCL have different viscoelastic properties. Although they share structural properties, they are stiffer and less elastic than the LCCL and the lateral band of the coracoacromial ligament. Their different mechanical properties change their risk of rupture during an injury.

The AC separation injury can range from mild to severe. The severity depends on the amount of ligament torn. If only one of the coracoclavicular ligaments is torn, grade one would be mild. If, on the other hand, the other ligaments are torn, grade two would involve the entire joint. The AC separation injury may even include other ligaments that stabilize the joint.

The AC and CC ligaments are separated by a bursa (CC) ligament, which helps differentiate the two. These ligaments are the most commonly affected ligaments in the shoulder. The AC and CC ligaments are located in the outer portion of the acromion.

Subclavian Artery

The subclavian artery passes behind the Scalenus anterior. It may ascend up to four cm above the clavicle or may rise at an intermediate point. The left subclavian artery is slightly narrower than the right. It is interconnected with the superior epigastric artery and the external jugular vein. Both of these veins supply blood to the shoulder and arm.

The subclavian artery carries oxygen-rich blood from the heart to the arms, shoulders, and neck. The left and right subclavian arteries come from the aortic arch. The left subclavian artery is the main blood supply for the left shoulder, while the right subclavian artery supplies the blood to the right shoulder and arm. Both arteries have many branches, and some branches supply blood to the thorax and head.

When an abnormality occurs in the subclavian artery, a medical professional will perform a physical exam to determine the condition of the artery. If there is compression of the artery, surgery may be necessary to open it. If blood clots are present, medications are available to dissolve them. In addition, regular checkups may prevent complications related to the subclavian artery.

If the subclavian artery is narrowed, the blood flow to the brain will be impaired. This may result in dizziness, blurred vision, and syncope. It can also cause numbness in the arm and reduced blood pressure on the affected side.

The subclavian artery begins on the right side of the aortic arch and travels toward the first rib. The artery then branches off into the axillary artery.

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