Frozen Shoulder / Capsulitis
Frozen shoulder or adhesive capsulitis is a condition characterised by pain and restricted shoulder movement. Although the disease is still poorly understood, it results in an inflammatory process, which causes the shoulder capsule to thicken and contract. The capsule surrounds the shoulder joint and in a normal shoulder it is soft and flexible thereby allowing the shoulder to move in a wide range of movement. As the capsule becomes inflamed and contracts, shoulder movement becomes restricted and the shoulder becomes stiff. The shoulder ligaments, which are imbedded within the capsule, are therefore also affected thereby resulting in further restrictions of shoulder movement.
The condition commonly presents in three phases;
- Phase I; The ‘Freezing’ phase. During this phase the shoulder becomes very inflamed and painful, with night pain often being reported. As the shoulder capsule contracts the movement becomes more and more restricted. This phase can last between 6 weeks and 9 months.
- Phase II; The ‘Frozen’ phase. During this phase the pain slowly begins to settle but the movement remains restricted. This phase may last 4 to 12 months.
- Phase III; The ‘Thaw’. Movement slowly returns to the shoulder. The duration of this phase is variable but can last between 6 and 36 months. Even at the end of this phase, some end range restrictions may still be present.
If the inflamed capsule is confined to just one area of the shoulder, thereby limiting some but not all shoulder movement, the condition is often referred to as a Capsulitis. If the inflammation affects the entire shoulder capsule, all movement may be affected and the condition may then be termed a Frozen Shoulder.
Causes & Risk factors
The cause of a frozen shoulder is poorly understood but essentially there are two types. A primary adhesive capsulitis occurs out of the blue and with no apparent cause. This form of the disease usually develops relatively slowly compared to the alternative form, a secondary adhesive capsulitis. A secondary frozen shoulder develops after a specific event such as an injury or indeed after surgery or prolonged immobilisation.
There are risk factors associated with the condition. Although the links with the disease remain poorly understood, patients with Diabetes, a Dupuytren’s contracture of the hand, hypothyroidism, hyperthyroidism, Parkinson’s disease, high cholesterol and heart disease can all be prone to developing Capsulitis or a Frozen shoulder.
The symptoms of pain and stiffness are common with many shoulder conditions. The diagnosis of a frozen shoulder can therefore only be made after a careful history and examination so that other conditions that can also affect the shoulder are ruled out. In a Secondary frozen shoulder, a second condition will be present and this often requires other investigations to determine the nature of the underlying condition that has resulted in the frozen shoulder.
- X-rays can be used to rule out other conditions such as calcific tendonitis and arthritis, which can also present with similar symptoms.
- MRI (Magnetic resonance image) can be used to look for other conditions, such as a rotator cuff tear, which may have predisposed the shoulder to the condition.
A true Frozen Shoulder will generally settle without intervention although this can take between one to three years. During this time the pain and stiffness slowly resolves although there can still be some residual stiffness that continues at the end of that period. More localised areas of capsulitis can resolve more quickly.
There are however options to manage the pain and stiffness associated with a Frozen Shoulder:
- Pain relieving medications, particularly anti-inflammatory medication, can be used to reduce pain, particularly in the early phases of this condition. Medication will however have little effect on the restricted range of movement.
- Physiotherapy is used to regain any lost range or to maintain the range of motion that you now have thereby preventing the condition from getting any worse. However, if the pain is too severe then unfortunately physiotherapy may be difficult to continue. If the physiotherapy is to be successful a home exercise programme is usually also needed.
- Injections; Corticosteroid injections can be used to reduce the inflammation to help reduce the pain. If successful, up to two or three injections can be undertaken. They are usually undertaken to help reduce the pain such that physiotherapy can be undertaken.
- An arthroscopic release of contracture(key hole) of the shoulder offers an effective way to manage both the pain and stiffness associated with the condition. This procedure is undertaken through two small 1cm incisions at the front and back of the shoulder. Any capsular contractures, which are restricting the shoulder movement, are divided. A gentle manipulation of the shoulder is often also done at the same time to gain further range. A post-operative physiotherapy programme is always an essential part of the treatment. In the case of a secondary adhesive capsulitis, where the initial injury involved a rotator cuff tear, a combined or staged procedure will be needed.