Muscle Breakdown: Posterior Deltoid
Table of Contents
What Is the Posterior Deltoid
The Posterior Deltoid is part of the Deltoid muscle. It is located on the upper posterior shoulder and is a superficial muscle.
Posterior Deltoid Muscle & Cadaver
Posterior Deltoid Function
The function of the Posterior Deltoid is to horizontally abduct the shoulder, externally rotate the shoulder and extend the arm behind the hips.
Posterior Deltoid Origin And Insertion
Posterior Deltoid Origin
The Posterior Deltoid originates from the spine of the Scapula.
Posterior Deltoid Insertion
The Posterior Deltoid inserts into the Deltoid Tuberosity with the rest of the muscles of the Deltoid.
Posterior Deltoid Action
The Posterior Deltoid helps to perform many everyday movements such as,
Pulling objects towards you
Extending the arm to reach for an object
Waving your arms above the head
Performing Jumping Jacks
Swimming
Lifting weights
Baseball
Helpful in many yoga positions
Reaching for things behind you
Posterior Deltoid Innervation
The Posterior Deltoid is innervated by the Axillary Nerve.
Posterior Deltoid Pain
Pain in the Posterior Deltoid can be the result of an injury. You can injury the Posterior Deltoid from overuse of the muscle over time, or from a sudden acute injury where you may feel a sharp pain in the muscle. Regardless of the type of Posterior Deltoid injury, symptoms of pain can include deep throbbing, swelling of the muscle, decreased range of motion of the muscle and muscle weakness.
It is important to see your doctor if you suspect you have an injury to the Posterior Deltoid as experiencing prolonged pain can be indicative of a muscle strain or tear.
Posterior Deltoid Tear
A Posterior Deltoid Tear can occur suddenly from an overload on or overstretch of the muscle. You will experience sharp pain and will be unable to perform the movements that the Posterior Deltoid is responsible for. Swelling, bruising and loss of strength in the muscle are all common symptoms.
Treatment for a Posterior Deltoid Tear is the same for a Posterior Deltoid Strain. Only in rare cases will you need surgery to repair a tear to the Posterior Deltoid. Often, the muscle will heal on its own in 4-6 weeks with a proper treatment plan.
Posterior Deltoid Strain
Repetitive movements and overuse of the Posterior Deltoid can increase your risk of experiencing a muscle strain. There are different categories of muscle strains based on the amount of injury to the muscle. A grade 1 strain is the least severe and involves some swelling and tightness in the muscle, however, your range of motion may not be affected. A grade 2 strain will result in limited movement of the Posterior Deltoid, and greater swelling and muscle pain. Finally, a grade 3 strain is the most severe type of strain where movement or use of the Posterior Deltoid is almost impossible. There will be severe pain and significant swelling in the muscle.
To treat a Posterior Deltoid Strain, rest, ice, heat and compression will all help to reduce pain. Visiting a Physiotherapist may also be beneficial to speeding up your recovery as they will provide you will light stretches and movements to help rehabilitate the muscle.
Posterior Deltoid Exercises
Bent Over Lateral Raise
Begin with your feet hip-width apart and knees slightly bent. Holding a dumbbell in each hand, bend the torso forwards until it is parallel to the floor. Be sure to keep the back straight. Brace the core and perform a lateral raise. Repeat this movement for 3 sets of 12 reps.
Barbell Bent Over Row
The Barbell Row is a great exercise to engage the Posterior Deltoid and the muscles in the back. To learn how to perform the Barbell Row, check out our exercise tutorial here.
High Pull
Using a cable machine, adjust the pulleys to be about chest height. Using a rope attachment, take a step away from the machine and pull the rope towards your chest. Be sure to pull the rope straight back so that your elbows are in line with the shoulders and wrists. Repeat this movement for 3 sets of 12 reps.
Posterior Deltoid Stretch
Cross Arm Stretch
Bring one arm across your chest so that the wrist is on the outside of the opposite shoulder. Use the remaining arm to cradle the crossed arm by forming a 45-degree angle at the elbow. Use the forearm of the bent arm to press the crossed arm into the chest. Hold this position for 30 seconds and then switch arms
Bent Over Stretch
Keep your legs straight and bend over at the hips. Let the arms hang down in front of you as you try to touch your toes. Hold this position for 30 seconds.
