Shoulder pain can be a problem with the shoulder joint itself or the muscles, ligaments and tendons around the shoulder joint. The shoulder is one of the most flexible joints in the body but this also means that it is one of the most unstable ones - and it can be easily injured. If pain is related to the shoulder it is made worse by moving the shoulder. Some leading causes of shoulder pain include muscle strain, tendonitis, bursitis and rotator cuff injuries. If you are over 40 and there is a marked reduction in your shoulder flexibility you may have another type of shoulder problem called “frozen shoulder” or adhesive capsulitis. This is caused by adhesions or growths in the capsule of the shoulder. These adhesions lead to a feeling like there is a tight band around the shoulder as well as difficulty moving it. Sometimes shoulder pain can be caused by referred pain from another part of the body such as a pinched nerve in the vertebrae of the neck, gallbladder or liver disease, or a heart problem. If you experience chest pain or difficulty breathing, contact emergency services immediately. 

Shoulder pain is often caused by an injury or trauma to the shoulder joint or the tissues surrounding the shoulder joint. A shoulder injury could be caused by a physical trauma from falling over or a sports injury for instance. It could also be caused by heavy lifting, an awkward movement of the shoulder, or from overuse. These injuries can affect the joint and cause shoulder pain for several reasons including:

Muscle strain
Muscle strain refers to the overstretching of the fibers of the shoulder muscles. This usually happens after repetitive movements or heavy lifting, and is a common cause of shoulder pain.

Tendon strain and ligament sprain
Tendons are collagen fibers which join muscles to bones and enable our body to move. When under strain tendons can be overstretched this is called a tendon strain or tendonitis. Ligaments are another type of connective tissue and they join bones together. Injury can lead to damage of the ligaments, called a ligament sprain.

Nerve compression
Pressure or compression of the nerves of the shoulder or the spinal nerves can lead to shoulder pain. This is when the tissues around the nerve (muscles, tendons, ligaments, bones) put pressure on the nerve. It can also be caused by problems with the discs in spine. Discs are the jelly-like substances sitting between vertebrae. Sometimes the outer casing of the disc can tear leading to the jelly leaking out and putting pressure on the nerve. 

Above: a diagram of disk bulge putting pressure on a spinal nerve.

Shoulder dislocation
If your shoulder is suddenly moved upwards and backwards it can be pulled out of its socket (dislocated). If this happens seek immediate medical help. A medical professional will need to “relocate” the shoulder for you. After this you will need to be put in a sling for several weeks, and once your doctor or orthopedic specialist has made sure there are no structural problems you may be referred to physiotherapy for muscle strengthening exercises.

Rotator cuff injury
The rotator cuff is comprised of four key muscles supraspinatus, infraspinatus, subscapularis, and teres minor. These muscles and their associated tendons are important in holding the shoulder joint together and maintaining its structural integrity. A rotator cuff injury relates to damage of any of the rotator cuff muscles or their tendons. Sometimes injury to the area can also affect the surrounding bursae as well. Bursas are the small fluid filled sacs which prevent tendons and muscles from rubbing against bones. When a bursa is inflamed it is called bursitis.

Above: A diagram of the 4 rotator cuff muscles which can be damaged in a rotator cuff injury.

Adhesive capsulitis (frozen shoulder)
Frozen shoulder is caused by inflammation in the shoulder capsule. The capsule is the membrane or casing which holds the bones, ligaments and tendons of the shoulder in place. In the case of frozen shoulder the joint capsule has growths called adhesions. These adhesions create a tight band around the shoulder leading to a marked reduction in your range of motion and discomfort. Often the exact cause of frozen shoulder is unknown however sometimes is can be caused by a shoulder trauma or injury. It can also be caused by chronic or ongoing inflammation in the shoulder joint. Risk factors for developing frozen shoulder include shoulder surgery or a history of rotator cuff injury or broken arms. Also people over 40 are more likely to develop frozen shoulder, and women are more likely to have it than men.

Above: A diagram of the shoulder joint, the arrow points to the area where the joint capsule is. Adhesions grow here and lead to the symptoms of frozen shoulder. 

The main treatment providers endorsed by ACC are:

Acupuncturists
Acupuncture is an effective treatment for a wide range of shoulder problems. For shoulder pain including rotator cuff syndrome and frozen shoulder, acupuncture is an effective and side effect free way of treating shoulder pain.  This is validated by recent trials which have determined how acupuncture is able to relieve pain.  Acupuncture is also helpful in releasing strained shoulder muscles and increasing the body’s immune response to repair and regenerate damaged tissues. For this reason acupuncture is an important treatment modality used by ACC to treat shoulder injuries. For chronic shoulder problems such as frozen shoulder or osteoarthritis in the shoulder joint acupuncture is helpful in reducing pain and increasing movement in the shoulder. Book an acupuncture treatment here.  

Physiotherapists
Physiotherapy focuses on the rehabilitation of injuries. Physiotherapists treat a wide range of conditions including back and neck problems, problems of the extremities as well as shoulder pain. Physiotherapy treatment usually involves a number of different techniques including massage, joint mobilisation and myofascial release. Individually tailored exercises are also an important part of physiotherapy. These exercises help to rehabilitate and strengthen the tissues of the shoulder.

Chiropractors
Chiropractors specialise in “adjusting” or manipulating the vertebrae of the spine. Sometimes pain can be caused by spinal vertebrae or the bones of your back being out of alignment. Chiropractors are able to move the bones of your back so that they can go back into the ideal position. This can benefit shoulder pain because some of the nerves and muscles which go to the shoulder joint come from the spine. Some specialist chiropractors also manipulate the shoulder joint itself.

Osteopaths
One of the primary focuses of an osteopath is to mobilise the joints and tissues of the body. Osteopaths employ a number of techniques to do this such as spinal manipulation, muscle release whilst muscles are under strain and myofascial release. Osteopaths generally treat the spine as well as another affected joint in the body. In the case of shoulder pain treatment would focus on the shoulder joint but also take into consideration the position of the spinal vertebrae which can influence shoulder pain.

Pain medication for shoulder pain
Over-the-counter pain medication like paracetamol or ibuprohan can give moderate relief from shoulder pain. For severe pain you may need prescription medication such as anti-inflammatories or analgesics (codeine or tramadol). Please consult your doctor if you are needing to frequently use over–the-counter pain medication and for the safe use of prescription medication.

Creams and gels
Topical products can help to promote blood flow in the muscles and tissues of the shoulder and this will help with shoulder pain. Visit your local health shop or chemist for more information.

Exercise and movement
Your shoulder pain will benefit from a moderate amount of exercise and movement. However, it is important to have a mixture of movement as well as rest as this will help to encourage your shoulder to heal. In the case of frozen shoulder it is very important to stretch your shoulder and keep it moving to avoid further stiffness in the shoulder joint. 

Use a cold or hot compress
It is very helpful to apply a cold compress to your shoulder within 48hours of any shoulder injury, using a bag or peas or an ice pack. However, after this apply hot compression e.g a wheat pack or hot water bottle. This will help to improve blood flow and reduce pain. 

Here are some general exercises for shoulder pain and shoulder injuries courtesy of ACC. Before using these exercises ask your healthcare professional if these shoulder exercises are right for you.