Complex Regional Pain Syndrome

Published: 22 Aug 2023

Complex Regional Pain Syndrome

What is it?

Complex Regional Pain Syndrome (CRPS) is a rare and debilitating condition characterised by severe pain affecting one or more limbs. The exact cause isn’t fully understood but is believed to be an abnormal response of the nervous system in response to trauma. In more than 90 per cent of cases, CRPS is triggered by trauma or injury with the more common triggers being sprains, fractures, burns, surgery, or limb immobilisation. Not everyone who experiences these events will develop CRPS. Much like a food allergy, some individuals respond abnormally to a trigger that causes no problem for others.

There are two types of CRPS:

  • CRPS-I, previously known as reflex sympathetic dystrophy syndrome, is when there is no confirmed nerve injury.
  • CRPS-II, previously known as causalgia, is when there is an associated nerve injury.

However, physiotherapy treatment does not differ between the two types.

How do I know that I have CRPS

There is no formal test to diagnose CRPS. The diagnosis of CRPS involves clinical history and an assessment of clinical criteria.

Key features of complex regional pain syndrome include:

  • Severe pain and hypersensitivity – pain that is often disproportionate to the initial injury or trauma.
  • Skin, hair and nail changes include differences in colour, texture or temperature.
  • Allodynia (that is, normal light touch or temperature change that is experienced as pain)
  • Hyperalgesia (that is, increased response to pain after the event)
  • Decreased range of motion and strength sometimes due to fear of moving the injured extremity
  • Swelling of the affected limb
  • Altered sweating

It is important to rule out other conditions such as joint arthritis, small or large fibre polyneuropathies, infections of the skin or blood vessels, vascular issues, and autoimmune conditions such as erythromelalgia, as these require different treatment.

How do you treat CRPS?

The treatment requires a multidisciplinary approach, including physical therapy, behavioural and psychological therapy, and medications to control pain. Early intervention is important to improve the chances of successful treatment and recovery. Most people recover from CRPS.

How can physiotherapy help?

Physical therapy is a vital part of the treatment of CRPS. Physiotherapy-guided exercises aim to keep the affected limb moving and lessen circulatory symptoms, reduce limb stiffness, and improve strength and function. Additionally, a combination of manual therapy and an exercise-based approach can address the secondary changes in the brain and its pathways associated with complex pain.



Dommerholt, J. (2004). Complex regional pain syndrome—2: physical therapy management. Journal of bodywork and movement therapies, 8(4), 241-248.

Marinus, J., Moseley, G. L., Birklein, F., Baron, R., Maihöfner, C., Kingery, W. S., & van Hilten, J. J. (2011). Clinical features and pathophysiology of complex regional pain syndrome. The Lancet Neurology, 10(7), 637-648.

Jänig, W., & Baron, R. (2003). Complex regional pain syndrome: mystery explained?. The Lancet Neurology, 2(11), 687-697.