title: Landmark-based versus ultrasound-guided ilioinguinal/iliohypogastric nerve blocks in the treatment of chronic postherniorrhaphy groin pain: a retrospective study.
abstract: BACKGROUND
  Chronic postherniorrhaphy groin pain (CPGP) is a debilitating condition, which is often refractory to conservative medical management. To our knowledge, there have been no studies directly comparing landmarked-based and ultrasound-guided approaches in this population.
  
  
  OBJECTIVE
  To compare the effectiveness of landmark-based and ultrasound-guided ilioinguinal/iliohypogastric nerve blocks in the treatment of CPGP.
  
  
  METHODS
  This is a retrospective chart review of patients who presented to our tertiary care pain medicine clinic with a diagnosis of CPGP. Inclusion criteria were the following: age >18 years, diagnosis of groin pain, and prior history of herniorrhaphy. Exclusion criteria included those who were seen for initial consultation but were lost to follow-up. Primary outcomes were 50% or greater reduction in pain on visual analog scale (VAS). Secondary outcomes were 30% or greater reduction in VAS pain score, changes in VAS pain scores, and reported complications.
  
  
  RESULTS
  A total of 36 patients were included in the study. Of them, 20 patients underwent the landmark-based and 16 underwent the ultrasound-guided techniques. There was no significant difference in baseline demographics. The average VAS score preinjection was 7.08 in the landmark-based and 7.0 in the ultrasound-guided groups (P=0.65). A total of 14 patients (70%) in the landmark-based and eleven patients (79%) in the ultrasound-guided groups experienced at least a 50% reduction in VAS scores. There was no statistically significant difference between the two groups (P=1.0), and no complications were noted. We also did not find a significant difference in terms of number of patients with 30% or greater reduction (P=0.71) and changes in VAS pain scores (P=0.64). No complications were reported in either group.
  
  
  CONCLUSIONS
  In our study, there was no statistically significant difference between the landmark-based and ultrasound-guided groups in terms of a reduction in VAS pain scores, and no complications were noted in either group.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA.
authors.forename: Drew
authors.initials: D
authors.lastname: Trainor
authors.affiliation: Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Moeschler
authors.affiliation: Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA ; Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Pingree
authors.affiliation: Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Hoelzer
authors.affiliation: Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: William
authors.initials: W
authors.lastname: Mauck
authors.affiliation: Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA ; Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Wenchun
authors.initials: W
authors.lastname: Qu
keywords: abdominal wall; anatomic landmarks; intramuscular injections; ultrasound