Rotator cuff injuries are one of the most common types of shoulder injury. The rotator cuff is the…
What is frozen shoulder?
Frozen shoulder is a painful and disabling condition in which the shoulder capsule becomes inflamed and stiff, resulting in the restricted range of motion of the shoulder. In some cases, the shoulder movements are so severely affected that the joint essentially becomes 'frozen'. Frozen shoulder is also known as adhesive capsulitis or shoulder contracture.
- Typically takes 2-9 months to develop;
- Is estimated to affect up to one in 50 people across the general population;
- Typically affects one shoulder, but in a small number of people both shoulders may be affected, and;
- Is commonly confused with a rotator cuff injury.
The shoulder joint capsule
The shoulder joint is surrounded by a fluid-filled capsule (which can be thought of as a sac) that holds the synovial fluid within the joint space. The capsule also holds together and supports the movement of the shoulder joint. If the capsule is too loose, the range of motion will be too great and the joint may dislocate. If the joint is too tight, the range of motion becomes too restricted to allow normal movement.
Causes and risk factors
In frozen shoulder, the capsule thickens and swells because of the formation of adhesions that have formed inside the capsule.
The cause of frozen shoulder is not yet clear; however, it appears to be more likely to occur in people with recent immobilisation of their shoulder following an injury or surgery. People with diabetes are also particularly prone to developing frozen shoulder.
Other risk factors for frozen shoulder include:
- Being female;
- Being aged between 40-60 years;
- Having Dupuytren's contracture;
- Having another underlying condition such as thyroid disease ( hyperthyroidism or hypothyroidism), Parkinson's or heart disease;
- Recently experiencing a long period of shoulder immobility due to injury, illness or surgery, and;
- Having poor posture and movement habits.
Signs and symptoms
The symptoms associated with frozen shoulder may begin gradually and worsen over time.
Some of the more general symptoms may include:
- Marked pain, especially when jerking the shoulder or making sudden movements;
- Reduced arm swinging with walking;
- Difficulty reaching above shoulder height;
- Inability to throw a ball;
- Inability to reach for something;
- Difficulty sleeping on the affected side;
- Stooped, rounded shoulders;
- Neck and back pain, and;
- Stiffness and swelling around the shoulder joint.
More specifically, the symptoms associated with frozen shoulder are typically classified across four phases:
- Initial phase - during this phase, pain is present, but the range of motion in the shoulder joint remains fairly unaffected:
- Freezing - during this phase, the capsule within the joint becomes increasingly inflamed and thickened. As it thickens, it results in a progressively restricted range of motion. The freezing phase is commonly associated with intense pain around the shoulder area, which may come and go:
- Frozen - during this phase there is no further reduction in the range of motion and the level of pain is greatly reduced, and;
- Thawing - during this phase, there is a gradual improvement in the range of motion, but there may be some associated weakness with the use of the shoulder.
If no treatment is received, each of these phases can potentially last for around 6-8 months.
Methods for diagnosis
Diagnosis of frozen shoulder is based on a physical examination and your detailed medical history. During the physical examination, you may be asked to perform several actions involving the shoulder and arm, so that your range of motion can be assessed. You may be asked to reach across your chest to touch the opposite shoulder, reach behind your back to scratch yourself and raise your arms above head height. Your doctor may also move your arm around the shoulder joint to evaluate your range of motion, which may help them distinguish between frozen shoulder and a rotator cuff injury.
Frozen shoulder and arthritis are the only two conditions that can cause the loss of motion in every direction of the shoulder. Frozen shoulder is the more common of these two conditions
Frozen shoulder can generally be diagnosed based on clinical examination alone, but imaging tests may be ordered to rule out other structural problems. An X-ray may be used to eliminate arthritis. An ultrasound or a magnetic resonance imaging (MRI) scan can be used to exclude rotator cuff injury.
Types of treatment
Frozen shoulder treatment involves controlling the pain and improving the shoulder's range of motion.
Pain-relief medications such as paracetamol or ibuprofen may help treat the pain. Icepacks or heat packs can also provide some pain relief. These should not be placed directly on the skin, as they may cause skin damage. Wrap them in a towel first.
Physical therapy is used to maintain the range of motion, stretch the shoulder joint and strengthen its tendons. It may take weeks for progress to become apparent.
Some people may find relief from their symptoms when corticosteroids are injected into their shoulder.
While under a general anaesthetic, the patient's shoulder joint is manually manipulated into different positions to help loosen overly tight tissues.
If more conservative treatments have not proved effective, surgery may be recommended for some people with frozen shoulder. The surgical procedure is carried out under general anaesthetic and uses an arthroscope to remove the scar tissue from the shoulder joint, which allows an increased range of motion. Sterile water can also be injected into the shoulder joint capsule to help stretch the tissue and increase the range of motion. It may take months after the surgery for the full range of motion to return.
- Stiffness and pain continue despite therapy;
- Possible fracture of arm if moved forcefully during manipulation, and;
- Surgical complications - infection, bleeding, swelling, stiffness and recurrence of frozen shoulder.
Most people recover from frozen shoulder within two years without treatment. Physical therapy and pain-relief medications can speed this up. Relapses in the same shoulder are uncommon.
Early treatment can help stop the progression of the condition. People with diabetes can reduce their risk of developing frozen shoulder by properly managing their diabetes.
A gentle, progressive range of motion exercises can help stretch the shoulder and reduce the risk of developing frozen shoulder after surgery or injury.