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We’ve all heard of it: frozen shoulder. But what actually is it? Physiotherapist Owen Sylvester looks at how it can be identified, the treatment options and how to keep active or train around the problem.

Unfortunately, we often find patients coming through our door at Pure Sports Medicine who have either self-diagnosed or been told that their painful and/or stiff shoulder is the blanket diagnosis of frozen shoulder. Of course, this may be right but often it isn’t the case. As one of the early frozen shoulder researchers Dr Codman famously said, “Frozen shoulder is difficult to define, difficult to treat and difficult to explain.”1 So, whether you’re a fitness professional who has clients with shoulder pain or even if you’re a shoulder pain sufferer yourself, it’s worth getting to grips with the facts on frozen shoulder and what it really means.

What is frozen shoulder?

Frozen shoulder, also known as adhesive capsulitis, is an extremely limiting condition, having a major impact on an individual’s function due to pain and a high level of restriction in movement. This has a maladaptive effect on a multitude of aspects of everyday life, ranging from basic personal hygiene to the ability to work and stay active. Understandably, these physical aspects lead to notable mental and emotional strains.2 This reinforces the importance of an early, correct diagnosis with clear communication and education about frozen shoulder and its management options, enabling people to live their normal lives.

Unhelpfully, the understanding of the pathophysiology of the condition continues to be limited. So much so that the terms ‘frozen shoulder’ and ‘adhesive capsulitis’ aren’t necessarily the most appropriate, but in the research world it’s proving difficult to find a more suitable term! Some of the changes found to occur within the shoulder in research to date include thickening of the rotator cuff interval, presence of inflammatory cytokines, contraction of the anterior and inferior joint capsule, increased neovascularity and reduced joint volume to name a few. It is generally agreed that the process is proliferative, fibroblastic and inflammatory in nature.1,5 In recent research, muscle guarding has been suggested to play a bigger role than once thought, as opposed to true capsular restriction. This was found when mobilising the shoulder under anaesthetic.4 Muscle guarding is the body’s protective mechanism around an injury site to avoid pain, leading to muscular contraction which limits movement, whereas a true capsular restriction involves changes to the structure of the shoulder capsule leading to reduced elasticity and, therefore, limiting movement of the ball and socket joint.

Fortunately, there are four key factors/clinical signs that help us diagnose frozen shoulder. Sufferers are normally 40–60 years old (closer to 50); those older or younger are likely looking at a different diagnosis. Both their active and passive range of motion is restricted to an equal level. One of these restricted movements must include external rotation by 50% or more. They must have a normal x-ray with nothing indicating alternative reasons for the stiffness.1,5,7 These key principles provide us with an accurate diagnostic criterion. It is important that stiffness is not confused by pain-limiting motion. There should be a true block to range of motion passively, particularly with external rotation, but often abduction and internal rotation are significantly limited too. It is sometimes difficult to establish an individual’s true stiffness due to pain causing muscle guarding; analgesic medication can help with this. Additionally, there can be alterations to movement patterns, such as hitching the entire shoulder girdle or rotating the trunk, which can give the impression of greater range of movement than is truly present.5 This is why accurately establishing passive range is essential.

The additional factors to be aware of will often be found in the history. The frozen shoulder sufferer will often have a rather innocuous onset with no particular mechanism of injury. In some cases, a frozen shoulder can develop following trauma, but it is important to consider the differential diagnoses with this. As the weeks progress, pain significantly increases and range of movement deteriorates. The location of pain is generally over the deltoid/upper arm region. They also often have regular sleep disturbance as they move in bed.5 These all raise suspicion but the previously mentioned key diagnostic criteria will change our hypothesis to a definite clinical diagnosis.

These aspects of assessment can all be addressed methodically if your client may be presenting with frozen shoulder but, generally, the diagnosis should come from a physiotherapy or appropriate medical clinic where all necessary investigations have been completed. If you are reading this from a sufferer’s point of view and thinking “this is me”, well it’s tricky to identify yourself and a professional assessment is essential.

There are medical factors that increase the risk, including a strong link with diabetes, family history, genetic predisposition and possibly hypothyroidism, so it’s always worth referring to any previous medical history taken with your clients.1 For completeness, if frozen shoulder has been identified, then having a medical screening to rule out any underlying contributing factors to the development of the condition would be of benefit.


It’s long been proposed since the 1940s that frozen shoulder follows a particular pattern of the following: a freezing phase whereby the shoulder is very painful and gradually losing range of motion; a frozen phase where the shoulder has reached maximal loss of range and may be less painful at this point; and a thawing phase where both movement and pain gradually improve. Roughly three months is spent in each phase.3,6 However, as time has gone by, this assumption has become increasingly contradicted with a varying range of recovery times and some experiencing longer-lasting chronic effects. Therefore, the age-old question of how long it will take to get better can’t be answered in a definitive way.1 This does lead us to how important the communication is. The individual must be made aware of this variation in recovery times, but also informed about the treatment options and their effectiveness. This, in conjunction with factors such as duration of symptoms, level of impact on quality of life and specific goals, can help create a shared decision on the onward management.

So, what can the individual do to improve? Well, encouraging movement through stretching exercises has been shown in some cases to be effective in restoration or prevention of further loss of range of movement. Research is limited with frozen shoulder but, even if the stretches help to combat the muscle guarding rather than stretch the capsule itself, then there is benefit.1,5,8 So, if you are training someone with frozen shoulder, have some of their session focused on a range of passive and active assisted shoulder movements, working into elevation beyond 90˚, external rotation and internal rotation. Don’t force the shoulder into these movements but work into their stiffness. The level of pushing into stiffness is gauged by pain levels at that point. Encouraging these individuals to work on this stretching regularly outside of their sessions is equally important; little and often is the idea with frozen shoulder rehabilitation. However, it obviously must be considered when this is appropriate as some cases are extremely painful and, if the sufferer is not coping well, escalation of care may be indicated. Or perhaps the individual isn’t engaging with this rehab and would rather be fast-tracked to other intervention options. Either way, the individual must be at the heart of the decision on how to approach the recovery.

Completing training around the problem is also appropriate. For example, if strength training is of interest to the individual, this can be continued but with the understanding that the shoulder has significant limitations, so will require adapted resistance training to keep it within its comfortable range. Most shoulder strength work will not be possible; however, shoulder isometric exercises are suitable provided the individual can tolerate this. Eccentric exercises have been suggested that they may help with the condition, but this is dependent on pain levels and available range.11,5Personal trainers and fitness professionals are the ideal candidates for adapting exercise to an individual’s requirements, so keep discussing symptom response and experiment with different approaches. Cardio work where the arm remains in a relatively neutral position (eg cycling/running) can be continued if the symptoms remain at a low level. Unfortunately, those involved in sports that require arm movements will be greatly affected by their restriction. But it is important they keep activity levels up, both to prevent deconditioning and to maintain a positive outlook.

In terms of other intervention options, manual therapy is usually applied by a physiotherapist and is shown to be effective alongside the prescription of specific shoulder exercises to promote increased mobility. Manual therapy is thought to assist with inhibition of muscle guarding. The therapist attempting to force increased shoulder motion is not advised. The use of heat in conjunction with joint manipulation can promote increased movement too.1,8,9 In some cases, people find a cooling option a soothing relief.5 This guidance, alongside exercise advice, is where physiotherapists and fitness professionals can work in unison to produce the best outcomes.

Moving onto more invasive options, steroid injections are useful for a multitude of musculoskeletal problems, with anti-inflammatory and analgesic benefits. A more favourable option is hydrodistension/hydrodilatation. Ultrasound-guided hydrodistension involves injecting large volumes of saline plus steroid and anaesthetic into the glenohumeral joint to distend the contracted capsule. This appears to get better results than the standard steroid injection and is commonly used. Research has found that manual therapy and exercises are essential immediately after this treatment.1,5,7 This is an important point, regardless of whether the individual goes on to require an intervention such as hydrodilatation. Being aware of what exercises they are expected to do and working on these until the intervention date will help maintain adherence and benefit outcomes. Again, the combined role of physiotherapists and fitness professionals can guide clients to the best outcomes following hydrodilatation.

Treatment options including acupuncture, shockwave therapy, taping, blood flow restriction training and many more don’t have much weight behind them for their use in the diagnosis of frozen shoulder, but some clinicians may offer them as an intervention to try.5

Finally, the most invasive is a capsular release surgery or manipulation under anaesthetic, with varying levels of success and popularity, but they are options if all others have failed. It’s important that individuals are made aware of these options, so they have a clear management route mapped out.1,10

So, what else could it be? There’s a broad range of shoulder pathologies that can cause pain and stiffness. Stiffness is a key feature of frozen shoulder, so it’s worth knowing there can be many other conditions that include this, such as osteoarthritis or following a fracture. This is why x-rays are useful to rule out these causes. You can also develop secondary stiffness following rotator cuff-related pain or ruptures and post-dislocation. Pain can cause reduced movement not necessarily due to stiffness and there is a whole host of causes including labral injury, rotator cuff tendinopathy and bursitis, ACJ injury or degeneration, rotator cuff tears, neuropathic pain stemming from the neck, plus many more. We of course have the nastier pathologies, like tumours and avascular necrosis, which further reinforce the importance of imaging. It’s important before self-diagnosing or suggesting to anyone they have frozen shoulder that these other options have been considered and ruled out and the criteria for frozen shoulder has been met.

The bottom line

  • Get it right! Frozen shoulder requires a correct diagnosis that considers all the other possibilities and effectively rules them out depending on clinical presentation and the correct tests. As in all cases, we must avoid incorrect diagnosis. Always signpost to a physiotherapist or appropriate healthcare professional.
  • Keep the shoulder moving! If there is a confirmed diagnosis, we want to encourage movement where tolerable. Incorporating shoulder mobility work in a gym and/or home-based programme is advised.
  • Keep the body moving! Completing exercise around the problem is encouraged, providing it’s adapted to the individual’s needs. As fitness professionals, you are the ones to guide clients with this, but we are here to help to ensure effective recovery and longevity.
  • Finally, make sure the individual is on the right path to recovery. They need to be informed of all the options and be at the heart of the route they wish to take alongside the guidance of the right healthcare professionals. Physiotherapists and sport and exercise medicine consultants can help to confirm a diagnosis but also provide guidance through the correct treatment pathway, with referral options to upper limb orthopaedic consultants if required. It’s important we take a multidisciplinary approach to frozen shoulder, with collaboration across all available specialist areas to help sufferers back to a normal and pain-free life.

Author Bio:

Headshot of Owen Sylvester









Owen Sylvester is a physiotherapist at Pure Sports Medicine. He has years of experience working in a specialist integrated musculoskeletal service, treating injuries sustained insidiously, post trauma or during sport and exercise. His knowledge covers both acute and chronic pain involving the upper limb, lower limb and spine, and he has a deep interest in the upper limb, including being part of an effective frozen shoulder pathway. To find out more about Pure Sports Medicine and Owen, visit

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