Please select the eligibility criteria that correspond to the clinical trial below.
Title: Spinal Cord Stimulation for Refractory Pain in Erythromelalgia
Brief Summary: Erythromelalgia is a rare disorder characterized by red, warm, and painful extremities, which is often precipitated by warm conditions. The pathophysiology is incompletely understood. The management of pain in erythromelalgia is challenging as no single therapy has been found to be effective. Response to pharmacotherapy varies, meaning that the physician has to take a stepwise trial and error approach with each patient. Consequently, this disorder is often associated with poorer health-related quality of life. There is currently no consensus or guideline on management of pain in erythromelalgia. Spinal cord stimulation is a widely applied therapy to treat severe chronic pain of various origin. Case reports and anecdotal evidence suggest that this therapy might alleviate refractory pain in patients with erythromelalgia.

The aim of this trial is to evaluate the efficacy of spinal cord stimulation for refractory pain in erythromelalgia.


Options:
A: Inclusion Criteria:

* Have undergone ≥1 back surgeries and developed chronic radicular pain that has remained refractory to non-surgical treatment for ≥6 months
* Minimum pain intensity of 5/10 on the leg pain NRS at baseline
* Successful two-week SCS testing period with tonic stimulation (≥2 points reduction in leg pain NRS from baseline). This means patients will experience paresthesia during the SCS trial period
* Mandatory assessment at the Multidisciplinary outpatient clinic for back-, neck- and shoulder rehabilitation, St. Olavs University Hospital

Exclusion Criteria:

* Coexisting conditions that would increase procedural risk (e.g., sepsis, coagulopathy)
* History of laminectomy or posterior fusion at the thoracolumbar junction, where percutaneous electrode end tips are routinely placed.
* Abnormal pain behavior and/or unresolved psychiatric illness.
* Unresolved issues of secondary gain or inappropriate medication use.
B: Inclusion Criteria:

1. A diagnosis of primary or idiopathic erythromelalgia
2. Patients ≥18 years who have developed chronic pain that has remained refractory to medical treatment for ≥6 months.
3. Minimum pain intensity of 5/10 on a numeric rating scale NRS at baseline.
4. Successful two-week SCS testing period with tonic stimulation (≥2 points reduction in pain NRS from baseline). This means patients will experience paresthesia during the trial period of spinal cord stimulation.

Exclusion Criteria:

1. Coexisting conditions that would increase procedural risk (e.g., sepsis, coagulopathy).
2. History of laminectomy or posterior fusion at the thoracolumbar junction, where percutaneous electrode end tips are routinely placed.
3. Abnormal pain behavior and/or unresolved psychiatric illness.
4. Unresolved issues of secondary gain or inappropriate medication use.
5. Unfit for participation for any other reason as judged by the study physician.
C: Inclusion Criteria:

* signed informed consent
* treated with spinal cord stimulation
* stable pain relief achieved

Exclusion Criteria:

* failure to give informed consent
* unable to use or understand how to handle the equipment, PGIC,VAS score or EQ-5D questionnaires.
D: Inclusion Criteria:

1. Have been diagnosed with chronic, intractable pain of the trunk and/or limbs which has been refractory to conservative therapy for a minimum of 3 months.
2. VAS ≥ 5
3. Be 18 years of age or older at the time of enrollment
4. Be willing and able to comply with study-related requirements, procedures, and visits
5. Be willing and capable of giving informed consent

Exclusion Criteria:

1. Pregnancy or potential for with unwillingness to use contraception
2. Have a current diagnosis of a coagulation disorder, bleeding diathesis
3. Have evidence of psychiatric or cognitive disorder, who are unable to cooperate with surgery and program control
4. Have a life expectancy of less than 1 year
5. Have a condition currently requiring or likely to require the use of diathermy
6. Other inappropriate situations determined by the researcher

Answer: B