Pain in Deltoid Muscle: Cause, Symptom and Treatment

[Dr. Sushanta Kumar Ghose]

The muscle that covers the tip of the shoulder is known as the deltoid muscle. This muscle is made up of three parts, the anterior part, the posterior part and the middle part. The role of the deltoid muscle is to connect the shoulder and the shoulder blade with the collarbone and the upper arm. The function of this muscle is to help the arm carry on objects from one position to the other, as well as, to rotate the arm. In certain cases, pain may occur which means that movements of the arm and shoulder are painful and uncomfortable. The severity varies from mild, moderate to severe pain, depending on the underlying cause.



What Causes Deltoid Pain?
In general, the pain results from a deltoid muscle injury or spasm. The common causes include:

Sports and Activity
Certain sports and activities lead to pain in deltoid, such as swimming, weight lifting, skiing, working with heavy tools, etc. Even repetitive activities such as typing, gardening or even holding the child can lead to deltoid muscle injuries.

Acute Injury
Any acute injury of the shoulder, such as a direct and sharp blow can result in deltoid muscle injury, leading to pain. This kind of injury is common in car accidents and shoulder dislocations.

Axillary Nerve Issues
The axillary nerves located near the neck stimulate the deltoid muscle when the shoulder and the arm are used. In cases when these nerves get damaged due to various reasons, the deltoid muscle can’t function correctly, often leading to deltoid pain. Shoulder weakness, muscle numbness and other symptoms are common.

Common causes of axillary nerve injuries include fractures, shoulder dislocation, improper use of crutches, long-term pressure on the nerve from splits or casts, direct injuries, deep infections, systematic disorders affecting the nerves, etc.

Trigger Points-Referred Pain
Pain in the deltoid muscle often is referred from nearby areas, even though it might seem that the pain is located in the deltoid muscle itself. Trigger points in the deltoid muscle exist as well, often being activated by repeated activities or shoulder injuries from a fall or accident.

What Are the Symptoms?
Common signs of pain in deltoid muscle include:

* Shoulder pain located in its tip, often spreading down the upper arm
* Shoulder pain when lifting or holding an object in front of the body
* Shoulder pain that decreases when the shoulder is at rest
* Shoulder weakness, etc.
* In severe cases of deltoid pain, a loss of range of motion, muscle weakness and even muscle atrophy may occur.

Three grades of deltoid muscle injury are known:

Grade 1 – only 10% of muscle fibers are damaged, leading to minor pain even though you may be able to continue any activity normally. In general, in such cases, the pain will tend to get worse when lifting heavy things. The recovery period will require 7 to 10 days and during this time the deltoid muscle will feel tight and achy.

Grade 2 – over 50% of muscle fibers are damaged, leading to a sharp pain when using the shoulder. This partial tearing of the deltoid muscle often leads to minor or moderate swelling of the affected shoulder as well. The recovery period will require 4 to 6 weeks and during this time the deltoid muscle will feel tight and achy for at least one week after the injury. Even carrying a grocery bag in such cases can be impossible.

Grade 3 – over 90% of muscle fibers are damaged, commonly referred to as a complete tear of the deltoid muscle. This is a severe shoulder injury accompanied with immediate severe pain, swelling of the affected shoulder and considerable bruising. You might not be able to use the arm totally for a certain period of time after the injury. The recovery period will require about 3 to 4 months, while muscle weakness, aching and tightness last at least 30 to 35 days after the injury.

How to Manage Deltoid Pain
1. Rest and Compress
In cases of deltoid muscle injury, resting the affected shoulder is very important. Ice packs and heat packs will speed up the recovery process as well. By resting your affected shoulder, you will give enough time to your deltoid muscle to heal. The recovery itself depends on the grade of the muscle tear.

On the other hand, ice reduces the inflammation which accompanies a shoulder and deltoid muscle injury. In cases of grade 1 strains, ice should be applied for 15 minutes, followed by a 15 minutes rest for the first day. In grade 2 and grade 3 strains, ice packs should be applied for a couple of days.

Heat packs should be applied in grade 1 strains after the first 24 hours, while for grade 2 and grade 3 strains, heat packs should be applied after 3 to 5 days of a deltoid muscle injury.

2. Stretching and Strengthening
During the recovery process, stretching and strengthening the deltoid muscle is very important. This is especially true when preventing future deltoid muscle injury. Once you don’t feel any more pain, you can start stretching the deltoid muscle. For this purpose, you can use a bottle of water or light weights to increase the resistance. Using a resistance band is also helpful when strengthening the deltoid muscle after a shoulder injury.

3. Massage
During the rehabilitation process following a deltoid muscle injury, sports massages are a part of this process. Make sure to choose a certified professional, helping your deltoid muscle remain loose and limber, warming the injured tissue at the same time.

In cases of grade 1 deltoid muscle injuries, you can start with a massage after the first 2 days, following shoulder rest, ice packs and heat packs. In cases of grade 2 and grade 3 deltoid muscle injuries, it will take some time until you can start massaging your injured shoulder.

4. Ultrasound
Ultrasound treatment is especially helpful in cases of grade 3 deltoid muscle injuries. This type of injury can benefit from other advanced rehab techniques as well, as it is a severe deltoid muscle injury with a prolonged recovery period affecting a person’s life and ability to perform daily tasks.

Ultrasound as a part of deltoid pain treatment should be performed by a certified professional. This type of treatment is characterized by the use of sound waves which are sent into the deltoid muscle. Ultrasound stimulation helps reduce pain and inflammation of the deltoid muscle.



Author: Sushanta Kumar Ghosh, Physiotherapy Specialist, DIU Medical Center