Frozen shoulder or adhesive capsulitis is a common condition affecting between 3-5% of the population. It affects women more than men and is more common between 40 and 60 years of age. While we still have much to learn about the condition, it is generally understood to be an inflammatory process of the shoulder capsule which results in thickening and fibrosis.
The condition is characterised by a painful and progressively stiff shoulder. Most times it occurs spontaneously, however may occur after trauma or injury to the shoulder. While we are getting better at identifying features on ultrasound and MRI imaging that appear consistent with frozen shoulder, there is still not a validated form of imaging which can diagnose the condition.
Diagnosis tends to be made clinically based on the presentation and physical examination. While often tricky to differentiate from other injuries to the shoulder in the very early stages, the clinical presentation as it progresses tends to be distinct. A gradual loss of range, particularly external rotation of the shoulder being a classic sign.
The condition can be broken into 4 phases;
Painful Phase – Synovitis and inflammation of the capsule has been triggered but the capsular tissue is still normal. There is a much higher concentration of immune cells in the capsule and increased growth of small nerve fibers and blood vessels into the capsule. It is certainly the most painful phase.
Freezing Phase – Immune cells release pro inflammatory cytokines and growth factors which result in the laying down of new fibrous tissue in the capsule and disorganisation of existing tissue. There is an increase in joint stiffness and loss of range but a gradual decrease in pain.
Frozen Phase – The capsule contracts and dense type II collagen is laid down. There is marked stiffness of the joint but often very little pain.
Thawing Phase – This involves a release of fibrosis and scarring, the pathophysiology for which is still not well understood. Typically, there is a gradual decrease in stiffness and increase in shoulder mobility between 12- 48 months with diminishing returns after.
Management of the condition will vary significantly depending on the stage of the condition. In the early, pain predominant stages, the main goal of management is to reduce inflammation and mechanical stress to the joint. Stretching at this point is not advised as this will simply increase the inflammatory response and worsen the condition. Anti-inflammatory medications and steroid injections at this point can be helpful in settling the condition which may assist in decreased degree of stiffness developed and faster recovery of function.
In the later, predominantly stiff phases, there is much better evidence for the application of capsular stretching and joint mobilisation to restore mobility of the joint, however when you are ready to commence this should be guided by your physio.
If you suspect you may be suffering from frozen shoulder, book an appointment today for an accurate diagnosis and plan to get you back to your best as quickly as possible!
