Persistent Postherniotomy Pain
Conditions
Keywords
Hyperalgesia, Persistent pain, deep pain, electrical stimulation, groin hernia
Brief summary
Sensory disturbances in persistent postherniotomy pain, include hyperalgesia from deeper structures as well as the skin. Whether this is one combined pain syndrome, where for instance deep pain leads to cutaneous hyperalgesia, or two isolated synchronous pain conditions, is unknown. By Giving pain free subjects an intense non-harmful electrical stimulation in deeper tissues in the groin and recording the skin sensory function, this hypothesis will be tested
Interventions
None listed
Sponsors
Rigshospitalet, Denmark
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* male, age \>18 yr, pain-free, caucasian
Exclusion criteria
* previous groin surgery, groin hernia, sensory disturbaces, use of painmedication, drug or alcohol abuse.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in skin pain detection threshold before and during deep electrical pain stimulation. | 14 days | Heat pain detection threshold by use of a Thermotester (Somedic AS Sweden) is assessed before and during deep electrical pain stimulation (6 of 10 point on a NRS scale. Deep pain stimulation is performed by two needle electrodes, placed under ultrasound guidance, 5 mm apart in various tissue and locations in the groin: 1. Musculus rectus abdominis dxt. ( 10 cm craniel to the external inguinal ring) - Subcutaneous, and muscular stimulation. 2. Spina iliaca anterior superior dxt. ( 2 cm lateral to the ilica spine) - subcutaneous, m obliquus externus and nervns ilioinguinalis stimulation. 3. External inguinal ring - subcutaneous and funicle stimulation. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Test-retest of primary outcome | 14 days | The primay and additional assesments are re-measured 14 days after the primary assemssment to allow evaluation of test-retest reliability. |
Other
| Measure | Time frame | Description |
|---|---|---|
| deep electrical and pain detection thresholds | 14 days | The detection- and pain detection thresholds to electrical stimulation will be assessed. An up-n-down staircase stimulation of single oulses of 0.04 mSeconds with increasing mA from 0.1 to a maximum of 60 mA is used. A total of 10 thresholds is recorded in the following locations. Musculus rectus abdominis dxt. ( 10 cm craniel to the external inguinal ring) - Subcutaneous, and muscular stimulation. Spina iliaca anterior superior dxt. ( 2 cm lateral to the ilica spine) - subcutaneous, m obliquus externus and nervns ilioinguinalis stimulation. External inguinal ring - subcutaneous and funicle stimulation. Musculus rectus abdominis sin. ( 10 cm craniel to the external inguinal ring) - Subcutaneous, and muscular stimulation. |
| warmth and mechanical detection and pain detection thresholds | 14 days | warmth and mechanical detection and pain detection thresholds are recorded in the right and left groin and right lower arm. A total of 10 repated mesures for each parameter is recorded. |
Countries
Denmark
Outcome results
None listed