Pain Trajectories in Severe Persistent Inguinal Post-herniorrhaphy Pain

Severe persistent postsurgical pain (PPP) remains a major healthcare challenge. In the third most common surgical procedure in the UK, inguinal herniorrhaphy, including 85,000 surgeries in 2015, an estimated 1,500 to 3,000 patients will annually develop severe PPP. While the trajectory of PPP is generally considered a continuation of the acute post-surgery pain, recent data suggest the condition may develop with a delayed onset. The present study evaluated pain-trajectories in a consecutive cohort referred to a tertiary PPP-center. Explanatory variables based on individual psychometric, sensory and surgical profiles were analysed.

Study Overview

• Status: Completed
• Conditions: Chronic Pain

Detailed Description

Severe persistent post-surgical pain (PPP) is a prevalent medical problem leading to impairment of physical and psycho-social functions in a large number of individuals.Severe PPP may significantly influence 4-8% of the surgical population, depending primarily on the surgical procedure and technique, but also patient-related pre-surgical factors.Updated criteria for PPP have recently been suggested. Inguinal herniorrhaphy qualifies for PPP-research due to a high surgical volume. Paradoxically, while the surgery is considered a minor procedure with limited tissue damage it is carried out in a territory with abundant nerve and vascular supply, and, complex musculoskeletal functions essential for locomotor actions. Persistent pain after inguinal herniorrhaphy may develop after a seemingly successful surgical procedure, and, is seen in a severe form in 2-4% of the patients associated with significant deterioration of the health-related quality of life.

The transition process from acute to persistent pain may be more complex than previously assumed, making the study of temporal pain trajectories interesting. Based on clinical experience from a nationwide research center in PPP following inguinal herniorrhaphy, the authors decided first, to perform a prospective exploratory cohort study examining graphical pain charts by planimetrics, attempting to construct a valid statistical sub-classification of the trajectories. Secondly, the relationship between the sub-classification of the trajectories, and, potential explanatory variables, based on individual profiles of pain, psychometrics, quantitative sensory testing, and surgical procedures, were analysed, using principal component analysis and logistic regression models.

• Study Type: Observational
• Enrollment (Actual): 95

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients with severe persistent pain after groin hernia repair with psychophysical disability referred to a dedicated tertiary center on a nationwide basis.

Description

Inclusion Criteria:

• Patients with severe persistent pain (>6 mo) after groin hernia repair referred to our center for PPP

Exclusion Criteria:

• Unable to cooperate with the sensory examinations

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Group I pain trajectories	Trajectories are examined by area-under-curve using normalized pain intensities (numeric rating scale values 0-10 [y-axis]) and normalized time points (years [x-axis]) in patients with sustained severe where the acute post-surgical pain continued into persistent post-surgical pain (PPP) with unchanged high-intensity pain	2014-2016
Group II pain trajectories	Trajectories are examined by area-under-curve using normalized pain intensities (numeric rating scale values 0-10 [y-axis]) and normalized time points (years [x-axis]) in patients where the acute post-surgical pain decreased significantly to low-intensity levels, but pain recurred developing into high-intensity PPP	2014-2016
Group III pain trajectories	Trajectories are examined by area-under-curve using normalized pain intensities (numeric rating scale values 0-10 [y-axis]) and normalized time points (years [x-axis]) in patients where repeat-surgery precipitated high-intensity PPP	2014-2016
Group IV pain trajectories	Trajectories are examined by area-under-curve using normalized pain intensities (numeric rating scale values 0-10 [y-axis]) and normalized time points (years [x-axis]) in patients where pre-surgical high-intensity pain continued unchanged post-surgically.	2014-2016

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain intensity	Numeric Rating Scale (NRS; 0-10 units)	2014-2016
Activity of Daily Living (ADL) score	Activities Assessment Scale (AAS; 8 specified physical activities; 0-8 units each)	2014-2016
Assessments of Anxiety and Depression	Hospital Anxiety and Depression Scale (HADS; 14 items scale; 0-21 units)	2014-2016
Assessment of Pain Catastrophizing	Pain Catastrophizing Scale (PCS; 13 item scale; 0-65 units)	2014-2016
Quantitative sensory testing (QST)	Mechanical and thermal detection and pain thresholds	2014-2016
painDETECT	Neuropathic pain questionnaire (15 items scale; 0-38 points; 0-12 points = neuropathic pain unlikely; 13-18 = existence of neuropathic pain cannot unambigously be rejected;19-38 points = neuropathic pain likely)	2014-2016
S-LANSS	Neuropathic pain questionnaire (7 items; minimal cumulated score 0 points, maximum cumulated score 24 points; a score of 12 or more suggests pain of predominantly neuropathic origin)	2014-2016

Collaborators and Investigators

• Sponsor: University of Copenhagen

Publications and helpful links

General Publications

• Chapman CR, Vierck CJ. The Transition of Acute Postoperative Pain to Chronic Pain: An Integrative Overview of Research on Mechanisms. J Pain. 2017 Apr;18(4):359.e1-359.e38. doi: 10.1016/j.jpain.2016.11.004. Epub 2016 Nov 28.
• Werner MU. Management of persistent postsurgical inguinal pain. Langenbecks Arch Surg. 2014 Jun;399(5):559-69. doi: 10.1007/s00423-014-1211-9. Epub 2014 May 23.
• Kehlet H, Jensen TS, Woolf CJ. Persistent postsurgical pain: risk factors and prevention. Lancet. 2006 May 13;367(9522):1618-25. doi: 10.1016/S0140-6736(06)68700-X.
• Werner MU, Kongsgaard UE. I. Defining persistent post-surgical pain: is an update required? Br J Anaesth. 2014 Jul;113(1):1-4. doi: 10.1093/bja/aeu012. Epub 2014 Feb 18. No abstract available.
• Gartner R, Jensen MB, Nielsen J, Ewertz M, Kroman N, Kehlet H. Prevalence of and factors associated with persistent pain following breast cancer surgery. JAMA. 2009 Nov 11;302(18):1985-92. doi: 10.1001/jama.2009.1568. Erratum In: JAMA. 2012 Nov 21;308(19):1973.
• McCarthy M Jr, Jonasson O, Chang CH, Pickard AS, Giobbie-Hurder A, Gibbs J, Edelman P, Fitzgibbons R, Neumayer L. Assessment of patient functional status after surgery. J Am Coll Surg. 2005 Aug;201(2):171-8. doi: 10.1016/j.jamcollsurg.2005.03.035. Erratum In: J Am Coll Surg. 2005 Nov;201(5):826.
• Reinpold WM, Nehls J, Eggert A. Nerve management and chronic pain after open inguinal hernia repair: a prospective two phase study. Ann Surg. 2011 Jul;254(1):163-8. doi: 10.1097/SLA.0b013e31821d4a2d.
• Pogatzki-Zahn EM, Segelcke D, Schug SA. Postoperative pain-from mechanisms to treatment. Pain Rep. 2017 Mar 15;2(2):e588. doi: 10.1097/PR9.0000000000000588. eCollection 2017 Mar.
• Werner MU, Bischoff JM. Persistent postsurgical pain: evidence from breast cancer surgery, groin hernia repair, and lung cancer surgery. Curr Top Behav Neurosci. 2014;20:3-29. doi: 10.1007/7854_2014_285.

Study record dates

Study Major Dates

• Study Start (Actual): August 21, 2014
• Primary Completion (Actual): November 10, 2016
• Study Completion (Actual): November 10, 2016

Study Registration Dates

• First Submitted: March 14, 2019
• First Submitted That Met QC Criteria: March 15, 2019
• First Posted (Actual): March 19, 2019

Study Record Updates

• Last Update Posted (Actual): February 22, 2024
• Last Update Submitted That Met QC Criteria: February 21, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: Hernia; Inguinal Herniorrhaphy; Long term follow up; Quantitative sensory testing (QST); Persistent postsurgical pain; Pain trajectory; Explanatory variables
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Chronic Pain
• Other Study ID Numbers: H-2-2011-023-TRJ

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be made available as a supplement to the published scientific article.
• IPD Sharing Time Frame: AUG-2020; 10 years
• IPD Sharing Access Criteria: Publicly available data
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No