Complex Regional Pain Syndrome : effects and reality.

By Isobel Radford

Published 11:14 EST, Sat September 4, 2021

Complex Regional Pain Syndrome is a rare neurological disorder that causes chronic/acute pain that can affect all areas of the body, but most commonly occurs in the extremities. For the majority of patients CRPS is usually started by an injury such as a sprain, broken bone or surgery and is characterised by intense pain.


A broken bone. Whether the radius or femur for the vast majority of the population the treatment plan is a straight path towards recovery and regaining normal function and life quality. However, 7 % who experience orthopaedic trauma gain CRPS (Complex Regional Pain Syndrome) [1] – a chronic condition potentially caused by improper function of the peripheral nerve fibres that carry messages to the brain. The condition is poorly understood by medical professionals across the world with limited knowledge surrounding the cause and treatment leaving patients with uncontrollable debilitating pain and a potentially severe disability resulting in a negative impact upon their quality of life. The poor comprehension of the disease means that an injury as simple as a broken bone or minor surgery can result in a condition that extends over months and years with no visible endpoint and with few global treatment centres it leaves patients to face allodynia, impaired muscle strength and dystonia indefinitely as well as  unbearable pain and inflammation.


Complex regional pain syndrome occurs in two different types, each of which have similar causes and symptoms, but different causes characterised by nerve damage. CRPS type 1 previously known as RSD typically occurs after an injury that did not directly cause damage to the peripheral nervous system within the limb. Type 1 occurs in around 90 % of patients with CRPS [8] . Many people diagnosed with CRPS type 2 have similar symptoms to type 1 but often occurs after a distinct nerve injury and was previously known as causalgia.


Due to the complex nature of the condition, misunderstanding and lack of knowledge from medical professionals, the cause remains unknown, but the disease has many potential causes. Most commonly it is believed to be a widespread abnormal response to an injury that damages the musculoskeletal system or central nervous system causing the bodily systems to malfunction resulting in a pain response beyond the scope of normality. The systems believed to be affected include : the immune system, the vascular system, the peripheral nervous system , the central nervous system and the musculoskeletal system. These systems are responsible for many of the body’s functions that are often impacted in people with CRPS, such as detecting pain and transmitting pain signals, triggering swelling and controlling temperature and movement.

immune system- responsible for defending the body against infection, vascular system for delivering oxygen


  • hyperalgesia – hypersensitive pain reception
  • allodynia – experiencing pain from light sensation on the affected skin area .
  • joint stiffness.
  • muscle spasms ( dystonia )
  •  insomnia
  • osteoporosis 
This image shows the dystonia , swelling and changes in skin colour that CRPS can cause. [9]

Controlling Biological Effects 

Chronic medical conditions invariably have multiple, interlinked causes which continually affect one another exacerbating a person’s overall condition. CRPS has to be looked at with this vewipoint due to the lack of knowledge of the original cause and widespread damage to multiple bodily systems to maximise recovery chance and end the persisting trauma. With insufficient awareness the biological impacts cannot be treated with a myriad of medications and procedures. Subsequently many have to resort to clinical trials for a slight glance of hope towards recovery such as the trial into the efficacy and safety of intravenous neridronic acid beginning in 2018 [3]. Fortunately, anticonvulsants such as gabapentin and TCA’s such as amitriptyline have been proven to help control the neuropathic pain following the development of the condition resulting from the original injury. Other treatments include intensive physiotherapy, nerve blocks, Botox injections and spinal cord simulation. [4. The Botox injections help to relax certain muscle groups that are causing dystonia and contributing to a patient’s condition. The nerve block is a form of therapy that targets the sympathetic nervous system and helps the body to control several involuntary bodily functions such as blood flow. However, this only manages the problem; it usually doesn’t solve it. This condition is time sensitive in cases where the patient develops dystonia increasing the physiological effects and risking muscle atrophy creating irreversible issues. 

Psychological Effects 

As with many pain conditions it is almost inevitable to have major psychological impacts on those who suffer ultimately impacting their daily life. People with severe CRPS often develop secondary psychological problems including depression, anxiety, and post-traumatic stress disorder (PTSD). All of which heighten pain perception, further reduce activity and brain function making it hard for patients to seek treatment and begin the path to recovery and rehabilitation [5]. A study into the psychological impacts by H. Hooshmand, M.D., and Eric M. Phillips Neurological Associates Pain Management Centre Vero Beach, FL  showed that out of 824  (CRPS) patients, one or more of the listed issues were present in every case except three : insomnia (92%), irritability, agitation, anxiety (78%), (depression (73%), poor memory and concentration (48%), poor judgment (36%), and panic attacks (32%) [6]. Without further research patients will continue to suffer with the impacts of this rare neurological disorder that causes endless suffering for around 1-3 million globally [7]. The psychological impacts could be reduced through the acknowledgement of patient’s symptoms from Doctors as well as support from family and the multidisciplinary team to help control this condition .


CRPS (complex regional pain syndrome) , is an incredibly detrimental disease to an individual’s quality of life due to limited knowledge and treatment options .For many years the cause was believed to be solely psychological meaning that treatment options were never explored until recently. However due to the unknown nature of this disease the development of treatment is difficult as researchers are unsure about which bodily system requires targeting. Not only are the biological effects extensive and debilitating but the psychological effects are equally as prevalent. Regardless of its rarity it is hoped that in the future medical researchers are able to find the cause and generate a cure. It is also to be hoped that awareness is created to ensure patients receive an accurate diagnosis to give them the best chance at rehabilitation. Currently in the United Kingdom there is only one adult treatment centre and two paediatric centres leaving many patients without access to treatment and specialist medical professionals. 

Isobel Radford, Youth Medical Journal, 2021