Anterior Cutaneous Nerve Entrapment Syndrome, Chronic Pain Syndrome, Diagnosis, Nerve Entrapment Syndrome
Conditions
Keywords
Diagnostic test for ACNES, Intraepidermal nerve fibre density (IENFD)
Brief summary
ACNES is a neuropathic pain condition of the abdominal wall. It is a clinical diagnosis based on patient's history and physical examination. No diagnostic test is available to confirm the diagnosis. This pilot study will determine if skin biopsies can be used as diagnostic test. Two 3mm biopsies will be taken and used to count the small nerve fibres in the skin. The number of small nerve fibres of the painful skin will be compared to non-painful skin. Skin biopsy and small fibre nerve count is already used as diagnostic test in patients with small-fibre neuropathy. The investigators hypothesize that patients with ACNES will have a reduced number of small nerve fibres in the affected skin, compared to the non-affected skin.
Interventions
PROCEDURESkin biopsy
Two 3mm skin biopsies from the abdominal wall will be taken. One at the triggerpoint of the pain, the second one at the contralateral, non-affected side of the abdominal wall. Lidocaine will be used for local anaesthesia of the skin, before the biopsies will be taken.
Sponsors
Maxima Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Masking description
The pathologists who will measure the nerve fibre density are blinded; they will not know if the biopsy is from the affected or non-affected side.
Intervention model description
Skin biopsies will be performed on patients with an unilateral ACNES. Biopsies will be taken at the triggerpoint (affected side) and contralateral, non-affected side of the abdominal wall. Affected vs non-affected will be compared. The non-affected side serves as control.
Eligibility
Sex/Gender
ALL
Age
21 Years to 50 Years
Healthy volunteers
No
Inclusion criteria
* Duration of pain \>3 months * Newly diagnosed unilateral ACNES * Fully completed intake questionnaire * Obtained written informed consent
Exclusion criteria
* Inability to understand Dutch language * Bilateral ACNES * Previously administered injections with corticosteroids at trigger point (injection with a local anaesthetic is allowed) * Previous Pulsed Radiofrequency (PRF)-treatment at trigger point * History of open abdominal surgery * History of neurectomy * Known neuromuscular or neurodegenerative disease * Antiplatelet or anticoagulants use or known coagulation disorders * Disorder known to cause a reduced IENFD; * Diabetes * Hypothyroidism * Renal failure * Vitamin B12 deficiency * Monoclonal gammopathy * Alcohol abuse (\>5 IU a day) * Malignancies * Medication that cause neuropathy (for example chemotherapy)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Intraepidermal Nerve Fibre density (IENFD) | Both biopsies will be taken at the same time, as their difference will be studied. The biopsies will be taken at the second outpatient visit, 2 or 3 weeks after the first visit, just after the second triggger point injection (standard of care). | Difference in IENFD (measured in IENF/mm) from both affected and non-affected side of the abdominal wall. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Treatment response | Treatment response will be assessed 2 to 6 weeks after each treatment (trigger point injections, PRF and neurectomy), as standard of care. | Patients will receive standard of care treatment for ACNES. Treatment is unsuccessful if \<50% pain reduction or when patients are not satisfied with their pain relief and want additional treatment. |
| Pain score | Assessed at first outpatient visit, used as baseline data. | Average pain score, assessed using the Numeric Rating Scale (NRS) 0-10 before start of treatment. 0 no pain, 10 worst possible pain. |
| Duration of pain | Assessed at first outpatient visit, used as baseline data. | Duration of pain in months before diagnosis |
Countries
Netherlands
Contacts
Primary ContactTom ten Have, MD
Outcome results
None listed