A few weeks after a stroke, a carer may notice that the weak hand has started to swell, the back of the hand is red and warm, and the patient pulls away at the lightest touch. Even when someone helps to bend the fingers gently, the patient may cry out in pain. This group of signs is very likely shoulder-hand syndrome (SHS), which medicine classifies as complex regional pain syndrome type 1 (CRPS type 1). It is a common complication in the subacute phase of stroke, but it is often mistaken for ordinary swelling and pain, and treatment is delayed.
This article looks at the condition purely from a physiotherapy point of view and covers three main points: how to recognise it early with a plain-language version of the Budapest criteria, why the reversible window has to be used quickly, and how a physiotherapist uses graded activity and desensitisation. It also explains which situations are red flags that need an immediate medical referral. Hemiplegic shoulder pain in general, shoulder subluxation and supportive care belong to the overview of shoulder problems after stroke and are not repeated here. This page concentrates on CRPS type 1 only. To tell the different causes of shoulder pain apart first, see the article on the six common causes of shoulder pain after stroke.
What is shoulder-hand syndrome (CRPS type 1)?
Shoulder-hand syndrome is a form of CRPS type 1, a regional pain syndrome with no specific nerve injury, and it is mostly seen in the weak, affected arm. To judge what type of pain the hand has, the first step is to sort the possible causes. It is best to read the article on the six common causes of shoulder pain and how to tell them apart first, to rule out subluxation, muscle spasm or rotator cuff problems, and then compare the clinical features of CRPS below. Medical literature shows that the rate and severity of SHS after stroke are closely related to the location of the stroke lesion, the degree of motor deficit, spasticity and sensory loss. The clinical course is typically divided into three stages, which worsen from swelling and redness (reversible) to trophic changes and tissue fibrosis (irreversible)(Pertoldi & Di Benedetto 2005).
The condition deserves its own article because it is both common and subject to a clear treatment window. Systematic reviews show that the prevalence of SHS after stroke varies widely, from 12.5% to 74.1%. About 30% of patients develop it within 6 months of the stroke, and some cases start as early as within one week of the stroke. Early recognition is often the key to keeping hand function.
Key point: If the weak hand after a stroke develops unusual swelling, redness, heat or pain, do not treat it as ordinary oedema. It may be a time-limited complication that is very hard to reverse once treatment is late.
Four groups of signs for early recognition (plain-language Budapest criteria)
Clinically, healthcare professionals use the "Budapest criteria" to assess CRPS. This validated set of criteria keeps a very high sensitivity (0.99) and raises specificity to 0.68 from that of the older criteria. It requires the patient to have at least 3 symptom categories and at least 2 clinical sign categories across four categories (Harden et al. 2010). Carers do not need to memorise the scoring, but the four areas below can be used as a guide to stay alert and ask for help early. The more items match, the sooner a professional assessment should be arranged:
The Budapest criteria are a clinical diagnostic tool for healthcare professionals. The four groups of signs listed above are only meant to help carers stay alert and ask for help early, and are not for self-diagnosis. Formal diagnosis, and the exclusion of other causes such as bacterial infection or vascular blockage, must go through assessment by a physiotherapist and a final diagnosis by a doctor.
The three stages of shoulder-hand syndrome and the timing of treatment
The course of shoulder-hand syndrome typically develops in three stages, and the later it is treated the harder it is to reverse. This is the core reason for stressing early recognition (Pertoldi & Di Benedetto 2005):
- Hand oedema, red and warm skin, obvious pain and allodynia
- Joint range of movement can mostly still be kept
- Early protection plus graded activity in this stage gives the best chance of reversal
- Stage 2: trophic skin changes, and joint stiffness starts to appear
- Stage 3: fibrotic contracture, and the hand becomes fixed in a deformed position
- If treatment is delayed to this stage, the aim changes to maintaining function and preventing worsening, and recovery is difficult
The stages of stroke recovery as a whole (acute, subacute, chronic and the commonly mentioned main recovery period) are not repeated here. See the stroke recovery timeline for details. One point only needs stressing here. Shoulder-hand syndrome is a complication layered on top of the overall recovery process, and its reversible window is shorter than the overall recovery period, so it must not be taken lightly.
Core physiotherapy approach: graded activity, desensitisation and joint protection
Many families instinctively think that the more it hurts, the more the patient must be pushed to move, and worry that stopping movement will make the joint stiff for good. For shoulder-hand syndrome, however, pushing the hand until the pain is severe only increases local inflammation and central sensitisation. A physiotherapist works the other way round and uses a graded, controlled approach that is pain-free or within what the patient can tolerate, to raise the tolerance of the affected limb step by step:
Graded activity and desensitisation
- Graded activity (pacing): active-assisted movement in a pain-free or tolerable range, with the amount increased slowly according to what the patient can accept, and never forced until it hurts
- Desensitisation: stimulating the skin with materials of different textures and temperatures, from light to heavy, so that over-sensitive skin gets used to outside touch again
- Active-assisted joint movement in a pain-free range, to keep joint range of movement and prevent stiffness and contracture
Reducing swelling and protecting the shoulder
- Raising the affected limb and applying pressure towards the heart (for example centripetal massage or a compression glove) to help reduce hand oedema
- Protecting the weak shoulder joint from injury through pulling. For shoulder subluxation and the use of supports, see the shoulder overview
- Muscle spasticity is one risk factor for SHS. How to manage spasticity itself is covered on another page and is not repeated here
Wider care of the weak shoulder is covered elsewhere on this website. This includes neuromuscular electrical stimulation (NMES) for shoulder subluxation, correct positioning and the safe range of movement of the hemiplegic shoulder, and supportive devices such as slings and tape. The management of spasticity as a risk factor is also covered on its own page. This page and those articles each have their own scope, and this page concentrates on the management of CRPS. To learn the principles of re-educating hypersensitivity and proprioception, see the pages on sensory re-education after stroke. If the affected hand also has numbness, reduced touch sensation or sensory loss (it is generally advised to carry out desensitisation and sensory re-education together, step by step according to the patient's tolerance), see managing numbness and sensory loss in the hand.
The role of mirror therapy in reducing pain
In addition to movement and desensitisation for the peripheral limb, an intervention that works directly on the cerebral cortex also has evidence for relieving CRPS pain. A randomised controlled trial in 48 patients with CRPS-1 of the upper limb after stroke showed that mirror therapy significantly reduced pain at rest and during movement and touch-evoked pain (allodynia), and also improved motor function scores on the Wolf Motor Function Test, with the benefit lasting to 6 months (Cacchio et al. 2009a). Even in patients with chronic CRPS-1 after stroke, mirror therapy still gave a significant pain reduction compared with covered-mirror or mental-imagery-only training (Cacchio et al. 2009b). This means that even when the earliest window for intervention has been missed, it is still worth referring the patient to try this kind of cortex-directed treatment.
This page only presents mirror therapy as a method for relieving CRPS pain. The full rationale of the therapy as a way to promote recovery of upper-limb movement, the home training dose and the specific steps are covered on the dedicated mirror therapy page and are not repeated here.
Red-flag referral: situations that must not be managed by physiotherapy alone
Another important duty of a physiotherapist is to identify the red flags that mean the problem is more than CRPS and medical care is needed straight away. If the patient has any of the following, a referral to a doctor should be made promptly. The doctor will arrange further tests or referral to a pain specialist as clinically needed:
- Suspected bacterial infection: persistent fever, pus from a wound, an unusually red and hot area, and very severe pain
- Signs of deep vein thrombosis: swelling, pain and heat in one calf
- Oedema that stays for a very long time, or pain that worsens sharply in a short time
- The cause is still not established, or the signs do not match typical CRPS
- After referral, the doctor arranges further tests or specialist follow-up as appropriate
The physiotherapist's work is early recognition, joint protection, guiding the patient through graded activity and desensitisation, and referring promptly to a doctor when warning signs appear. Do not rely on passive modalities alone for a long time and delay seeing a doctor. The later shoulder-hand syndrome is found and treated, the harder it is to recover hand function.
Limits of the research evidence for physiotherapy in shoulder-hand syndrome
Many "treatments" for CRPS or shoulder-hand syndrome are offered, but a responsible physiotherapy team has to state clearly what the research evidence shows. So far, the 2022 Cochrane systematic review (pooling data from 34 RCTs and 1,339 people) found that multimodal physiotherapy gives only a small improvement in disability at 12 months, and the certainty of evidence was rated "very low" for every comparison (Smart et al. 2022). In other words, physiotherapy has clinical value, but no single passive modality can guarantee complete pain relief or cure.
For acupuncture, a systematic review and meta-analysis on post-stroke SHS showed that acupuncture combined with rehabilitation training may help motor function and relieve pain, but the certainty of evidence for all clinical outcomes was also rated "low" (Liu et al. 2019). This article cites the study only to assess the evidence objectively. It does not recommend acupuncture as a main treatment and does not cover any herbal medicine or supplements. In summary, the clearest value of physiotherapy in managing CRPS lies in early recognition, joint protection, graded activity and desensitisation, and timely referral, and it does not lie in relying on a single passive pain-relief method.
Set reasonable expectations: The main goal of physiotherapy is to stop the condition worsening while it is still reversible, and to do everything possible to keep hand function. It does not guarantee a complete cure. If anyone advertises that a single course of treatment can cure CRPS, treat the claim with great care.
Dividing the work with occupational therapy
When hand oedema and pain interfere with daily activities such as dressing, eating and personal care, the related compensation strategies, the use of assistive devices and training for unilateral neglect are the professional area of occupational therapy. It is advisable for this to work alongside physiotherapy. See occupational therapy after stroke for details. This page keeps to a purely physiotherapy focus: explaining the pain mechanism, planning graded activity, protecting the joint and deciding on referral.