A National Center for Persistent Severe Pain After Groin Hernia Repair

This prospective, consecutive cohort study presents nationwide 5-year outcome data on patients with severe persistent pain after groin hernia repair (SPG).

The inclusion criteria were SPG-related impairment of physical and social life. Two-hundred-four out of 222 patients (92%) were analyzed. Relevant surgical records were obtained, and examinations were by standardized clinical and neurophysiological tests. Patients demonstrating pain sensitivity to pressure algometry in the groin were evaluated regarding exploratory surgery, while patients with putative neuropathic pain received pharmacotherapy. Questionnaires at baseline (Q0) and five-year (Q5Y) were used in outcome-analyses of pain-intensity (numeric rating scale \[NRS\] 0-10) and the pain-related effect on the activity-of-daily-living (Activities Assessment Scale, AAS).

Severe persistent pain after groin hernia repair (SPG) causes psychophysical disability and impairs quality-of-life for a considerable number of individuals each year.1-3 In the United States, 600,000 groin hernia repairs (GHR) are performed annually, and a conservative estimate is that 2%, corresponding to 12,000 individuals, each year will develop this debilitating pain condition.4 The management of SPG remains a daunting challenge to the medical profession 5, often requiring multidisciplinary efforts.1,6 Several surgical procedures have indicated substantial pain-relieving effects in SPG1,7 however few well-powered, controlled studies have been presented.8,9 In pharmacological and neuromodulation procedures, most studies are still case-based or uncontrolled.

In 2010, the authors established a dedicated tertiary center for SPG-patients open for referral on a nationwide basis. The objectives were, first, to analyze the pathophysiological mechanism behind the pain, second, to implement optimal medical and surgical pain management and third, to perform clinical SPG-research projects. Standardized clinical and neurophysiological tests guided the management paradigm for each patient. Treatment outcomes were evaluated prospectively using baseline questionnaires (Q0) and a 5-year questionnaire (Q5Y) mailed at the end of 2014 to all patients referred to the center.

The focus of the present study is first, to present clinical, neurophysiological and psychometric data on SPG-patients at referral, and second, to evaluate and compare efficacies of exploratory surgical and non-surgical treatment, based on a consecutive follow-up cohort of 222 patients.

Eligibility Criteria:
Inclusion Criteria:

* Severe persistent pain after groin hernia repair (activity-related or maximal pain intensity \> 7 NRS-units \[numeric rating scale 0-10\])
* Severe persistent pain after groin hernia repair-related serious impairment of working and social life.

Exclusion Criteria:

* Minors or persons of legally incompetence
* Participants, who do not speak or understand Danish
* Participants, who cannot cooperate with the investigator or the examination procedure
* Recurrent hernia
* Known neurological disease or disorders in the groin area of other origin
* Psychiatric disease
* Abuse of alcohol or drugs - according to investigator's evaluation