Surgical management of chronic inguinal pain syndromes - Liespijn

Results of our study are in concert with previous reports. In general, approximately threequarters of the patients will benefit from a neurectomy. Unfortunately, one fourth continuesto suffer from severe pain. If one studies the literature, reasons for treatmentfailure are unclear. Several factors may be important. First of all, appropriate patientselection is crucial. Patients with peripheral nerve injury may develop sensitization of thecentral nervous system over time. As a rule these patients are refractory to surgicalperipheral nerve interventions but should be treated with pain medication. Second, anadequate surgical technique is of great importance. The affected nerve needs to beidentified in a scarred operative field and resected as far proximal and distal as possibleburying the nerve ends in healthy muscular tissue. To prevent neuroma formation inunaffected neurectomized nerve ends, we believe that only the affected nerve(s) shouldbe removed, ‘the tailored approach’. A learning curve is present and failures significantlydepended on previously received pain treatment.A surgical neurectomy provides good long-term pain relief for postherniorrhaphy groinneuralgia in the majority of patients. Hernia surgeons should take their responsibilityfor this iatrogenic complication and incorporate selective neurectomy in their surgicalarmamentarium. Future research should focus on identifying additional factors associatedwith unfavourable surgical outcome.As high level evidence based treatment regimes for iatrogenic inguinal pain syndromesare currently lacking, patients usually receive a random combination of pain medication,local nerve blocks or an occasional surgical neurectomy. A randomized controlled trial('GroinPain Trial') was constructed to identify the optimal treatment modality in thispopulation. In chapter 7 aim and rationale of this trial are presented. Adult patientswith chronic postherniorrhaphy inguinal pain (> 3 months) caused by inguinal nerveentrapment with a temporary but significant pain reduction after a lidocain nerve blockare eligible for randomization. They either receive repetitive nerve blocks with lidocain,corticosteroids and hyaluronic acid, or a 'tailored' surgical neurectomy. Patient enrollmentstarted in February 2006 and is expected to end in June 2011. Initial results will beavailable towards the end of 2011. This trial is the first randomized controlled effortcomparing two invasive treatment modalities for peripheral inguinal nerve entrapment.As awareness and knowledge on chronic neuropathic pain after inguinal herniorrhaphyin the near future is expected to increase, findings of this trial will aid in optimizingcare for this patient population.Pfannenstiel incisions are also incidentally associated with chronic lower abdominalpain due to nerve entrapment (2-4%) 2 . Treatment options include peripheral nerve blocksor a neurectomy of neighbouring nerves. Knowledge on adequate (surgical) managementis limited. In chapter 8 we assessed long-term pain relief after local nerve blocksor neurectomy in patients suffering from chronic pain due to Pfannenstiel-inducednerve entrapment. Patients treated for iliohypogastric and/ or ilioinguinal neuralgiafollowing a Pfannenstiel incision received a questionnaire assessing current pain intensity(by 5-point Verbal Rating Scale), complications and overall satisfaction. Twenty-sevenwomen with Pfannenstiel-related neuralgia were identified over a seven-year period.A single diagnostic nerve block provided long-term pain relief in 5 patients. This phenomenonmay be explained by resetting the pain threshold to normal levels. A similareffect is occasionally observed in postherniorrhaphy groin neuralgia. Satisfaction in theremaining women undergoing neurectomy (n=22) was good to excellent in 73%,moderate in 14%, and poor in 13%. Smaller series show similar success rates 25,26 . Interestingly,successful treatment improved sexual intercourse-related pain in most females,a phenomenon that has never been described before in literature. Co-morbidities (endometriosis,lumbosacral radicular syndrome) and earlier pain treatment were identifiedas risk factors for surgical failure. Some cases of treatment failure may also beexplained from the concept of genetic susceptibility for chronic pain syndrome developmentas described in postherniorrhaphy groin pain as well 7 . This study demonstratesthat peripheral nerve blocking provides long-term pain reduction in some individualswith post-Pfannenstiel neuralgia. An iliohypogastric or ilioinguinal nerve neurectomyis a safe and effective procedure in most remaining patients. Gynaecologists must beprepared to offer a surgical consultation to this group of patients.5. Occupational disability after inguinal hernia repairResumption of daily leisure activities and occupational obligations is considered animportant outcome measure after hernia repair. However, the exact percentage of painpatients confronted with occupational disability is unknown. In chapter 9 the effect ofoperative and non-operative treatment on resolving occupational disability due to postherniorrhaphyinguinal neuralgia is evaluated.All relevant studies on treatment for postherniorrhaphy inguinal neuralgia were reviewedwith respect to effect on occupational disability. A recently published registry ofpatients with postherniorrhaphy neuralgia treated by neurectomy was analyzed foroccupational disability. Patients were contacted by telephone and given a set of predeterminedquestions concerning pre- and postoperative disability. Finally, a cost-benefitanalysis was made.Only 4 out of 23 studies on neurectomy for inguinal neuralgia reported on occupationaldisability as an outcome measure. These few studies demonstrated that some 56 to 100%of the patients could resume their occupational obligations after pain treatment. Studieson non-operative pain treatment and occupational disability appeared unavailable.Forty-eight patients previously treated by neurectomy were analyzed for occupationaldisability. Severe pain disabled 13 patients and a neurectomy resulted in total recoveryin 7 (7/13, 54%). An estimating cost-benefit analysis showed that effective pain treatmentsuch as a tailored neurectomy can save a minimum of € 1.8 million of workers’ com-142 Chapter 10143