Overview

Frozen shoulder, also known as adhesive capsulitis, can be a painful condition of the shoulder. It is often characterised by pain, stiffness and its hallmark sign is reduced range of motion. Frozen shoulder is a long term inflammatory condition that involves thickening of the shoulder joint capsule, leading to the formation of adhesions and fibrosis. This results in the tightening and stiffening of the capsule, restricting movement and causing pain. Frozen shoulder predominantly affects individuals between the ages of 40 and 60, with women being more commonly affected than men. While the exact cause is often unknown, certain risk factors such as diabetes, thyroid disorders, and previous shoulder injuries or surgeries may predispose individuals to develop frozen shoulder. Additionally, prolonged immobilisation of the shoulder joint, such as after surgery or injury, can increase the likelihood of developing this condition. Interestingly, frozen shoulder has a strong link with stress and anxiety, often occurring following a stressful life event, however the exact mechanisms behind this are unknown. Frozen shoulder can significantly impact daily activities and quality of life, emphasising the importance of early diagnosis and appropriate treatment interventions to alleviate symptoms and restore shoulder function.

 

Anatomy 

The shoulder joint is a complex structure comprising the humerus (upper arm bone), scapula (shoulder blade), and clavicle (collarbone), along with associated muscles, ligaments, and tendons. In frozen shoulder, inflammation and thickening of the shoulder joint capsule occurs, leading to adhesions and fibrosis within the capsule. This process restricts the normal gliding motion of the humeral head within the joint socket, causing stiffness and reduced range of motion. The surrounding structures, including the rotator cuff muscles and tendons, also play a role in supporting and stabilising the shoulder joint. Understanding the anatomy of the shoulder is essential for diagnosing and treating frozen shoulder effectively, as it helps us target specific structures for intervention and rehabilitation.

Causes 

Frozen shoulder, or adhesive capsulitis, can arise from various causes, though the exact etiology is often unclear. One primary cause is inflammation and thickening of the shoulder joint capsule, leading to the formation of adhesions and fibrosis. This can result from trauma, injury, or prolonged immobilisation of the shoulder joint, such as after surgery or injury. Certain medical conditions, including diabetes, thyroid disorders, and cardiovascular disease, have also been associated with an increased risk of developing frozen shoulder. Hormonal changes, aging, and genetic predispositions may contribute to the condition as well, with frozen shoulder being most common in females (up to 70% of cases) over the age of 40. Additionally, repetitive strain or overuse of the shoulder joint can lead to inflammation and subsequent adhesive capsulitis. Understanding these potential causes is essential for effectively managing and preventing the development of frozen shoulder.

 

Diagnosis 

When diagnosing frozen shoulder, we place a lot of importance on listening to how your pain started, what brought it on and how it progressed. This will often give us an indication that frozen shoulder may be present and can help to indicate what stage it is in. 

 

Our objective testing will start by assessing your shoulder range of motion, which will often indicate whether frozen shoulder is present or not. From here, we look at strength tests using force dynamometry and then use functional tests to gauge your functional capacity. This information will allow us to judge whether it is in fact frozen shoulder, if any further imaging is required, and what stage of frozen shoulder it may be (see below!), which is very important for management. 

Stages

Frozen shoulder progresses through 3 stages:

  1. Freezing Stage: During this phase, movements of the shoulder can be painful and range of motion may decrease. This stage typically spans from 2 to 9 months.
  2. Frozen Stage: Pain may subside somewhat in this stage, but the range of motion in the shoulder can become more limited. This phase lasts from 4 to 12 months.
  3. Thawing Stage: Improvement in pain and mobility starts to occur during this phase, which spans from 5 to 24 months.

The time frames of all of these stages can differ significantly from person to person, with frozen shoulder typically lasting between 1-3 years. Whilst it is a condition that takes time to heal, research does indicate that a vast majority of cases recover really well, with minimal need for medication or surgery. 

Management 

 

Physio is important in the management of frozen shoulder, helping to alleviate pain, maintain available range of motion, and improve shoulder strength and function. Soft tissue release techniques can be used in the acute stages to address muscular tightness and reduce stiffness around the shoulder joint capsule. Range of motion exercises are then introduced gradually to stretch and mobilise the shoulder joint, including passive, active-assisted, and active exercises tailored to your level of comfort and tolerance, which will be determined based on the stage of frozen shoulder you are in. Additionally, strength training exercises targeting the shoulder muscles, particularly the rotator cuff and scapular stabilisers, are incorporated to enhance shoulder stability and support. These strength exercises will become progressively more important towards the end stages of rehab as the ‘Thawing’ stage takes place and pain and range of motion improve. This will help build the strength and range to prepare you to return to your day to day activities!