We’ve all heard of it; frozen shoulder. But what actually is it? Unfortunately, we often find patients coming through our door that 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’. 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. We aim to provide some clarity on what Frozen Shoulder is, how it can be identified, what the treatment options are, how to keep active or train around the problem, and finally if not Frozen Shoulder, then what else could it be?
Frozen Shoulder, also known as Adhesive Capsulitis, is an extremely limiting condition having a major impact on an individual’s function due to both 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, childcare, activities of daily living, the ability to work, but also to keep active and do the exercise they enjoy. Understandably, these physical aspects of the condition lead to notable mental and emotional strains. This reinforces the importance of an early, correct diagnosis with clear communication and education on frozen shoulder and its management options, enabling people to live their normal lives.
Unhelpfully, the understanding of the pathophysiology (physiological processes/effects) 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 to the rotator cuff interval, presence of inflammatory cytokines (a type of protein made by certain immune/non-immune cells), contraction of the anterior and inferior joint capsule, increased neovascularity and reduced joint volume, to name but a few.
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. Muscle guarding is the bodies 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.
So, what do we look out for? Fortunately, there are four key factors/clinical signs that really help us diagnose Frozen Shoulder. Sufferers are normally between 40 – 60yrs old (closer to 50), if people are older or younger then you’re 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. 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. This is why accurately establishing passive range is essential.
The additional factors to be aware of will often be found in a person’s 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. These all raise suspicion but the previously mentioned key diagnostic criteria will change our hypothesis to a definite clinical diagnosis.
Also there are some medical factors that increase the risk, including a strong link with diabetes, family history, genetic predisposition and possibly hypothyroidism. 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 is beneficial.
These aspects of assessment can all be addressed in a methodical way, and if you are reading this and thinking ‘this is me, this is me’, well, these things are tricky to identify yourself and a professional assessment is essential.
It has long been proposed since the 1940s that frozen shoulder follows a particular pattern of: 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 then a thawing phase where both movement and pain gradually improve; roughly 3 months is spent in each of these phases. 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 will it take to get better?’ can’t be answered in a definitive way. This does lead us to consider how important the communication is. A person must be made aware of this variation in recovery times, but also be informed on what the treatment options are and their respective 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 you do to improve your Frozen Shoulder? 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. It’s worth mentioning that research across the board 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. So, if you are strength training, for example, it would be beneficial to have some of the session focused on a range of passive and active assisted shoulder movements working into elevation beyond 90 degrees, external rotation and internal rotation. The idea with this is not to force the shoulder into these movements but to work into their stiffness. The level of pushing into stiffness is gauged by pain levels at that point. Working on this stretching regularly outside of fitness sessions is equally as important; little and often is the idea with Frozen Shoulder rehabilitation. However, it obviously must be considered when this is appropriate as some Frozen Shoulder cases are extremely painful and if you’re not coping well, escalation of medical care may be needed. Or perhaps, you would rather be fast-tracked to other intervention options. Either way, you must be at the heart of the decision on how to approach the recovery.
Completing training around the problem is also necessary. For example, if strength training is your preferred form of exercise, this can be continued but understanding that the shoulder has significant limitations so will therefore require adapted resistance training to keep the shoulder within its comfortable range. Most shoulder strength work will not be possible; however, shoulder isometric exercises are suitable provided you can tolerate this. Eccentric exercises have been suggested to help with the condition, but this is dependent on pain levels and available range. Strength & Conditioning Coaches, Personal 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, e.g., cycling/running, can also be continued if the symptoms remain at a low level. Unfortunately, those involved in any sports that require arm movements will be greatly affected by their restriction. But it is important to keep activity levels up by some means, both to prevent deconditioning and to maintain a positive outlook.
In terms of the other intervention options, we have manual therapy which is usually applied by a physiotherapist. This has been shown to be effective alongside the prescription of specific shoulder exercises to help promote increased shoulder mobility. Manual therapy’s role in this 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. In some cases, people may find a cooling option such as icing is also a soothing relief.
Moving onto more invasive options, we have the well-known steroid injections that are useful for a multitude of musculoskeletal problems with anti-inflammatory and analgesic (pain relieving) benefits. A more favourable option in the UK is the use of hydrodistension/hydro dilatation. Ultrasound guided hydrodistension is a procedure that involves injecting large volumes of saline plus steroid and anaesthetic into the glenohumeral joint, with an aim of distending the contracted capsule. This appears to be getting better results than the standard steroid injection and are commonly used in musculoskeletal Frozen Shoulder clinics. Research has found that manual therapy and exercises are essential immediately after this treatment. This is an important point, regardless of whether you go on to require an intervention such as hydro dilatation. Being aware of what exercises you are expected to do and working on these up until the intervention date will help. Again, the combined role of physiotherapists and fitness professionals can guide you to the best outcome following these treatment types.
There are a range of treatment options including acupuncture, shockwave therapy, taping, blood flow restriction training and many more that really don’t have much weight behind them for their use in the treatment of frozen shoulder, but some clinicians may offer it as an intervention to try.
Finally, the most invasive is a capsular release surgery or manipulation under anaesthetic with varying levels of success and popularity, but they are options to be considered if all the above have failed. It is important that people are made aware of these options, so that you can have a clear management route mapped out.
So, what else could it be? Without going in to too much detail, there’s a broad range of shoulder pathologies that can cause both 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. You will see this stiffness with osteoarthritis or following a previous fracture. This is why x‑rays are useful to help rule out these causes. You can also develop secondary stiffness following rotator cuff related pain or ruptures, as well as 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 in this case. 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.
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