title: Outcomes of Ultrasound-Guided Trigger Point Injection for Abdominal Wall Pain.
abstract: BACKGROUND
  Abdominal wall pain (AWP) is an important cause of chronic abdominal pain. History and physical examination are critical to the diagnosis of AWP. Trigger point injection (TPI) using either a steroid or a local anesthetic or a combination of both is often used to treat AWP.
  
  
  OBJECTIVE
  To determine the efficacy of ultrasound-guided TPI and to determine the predictors of a successful response.
  
  
  METHODS
  Patients who received ultrasound-guided TPI between July 2010 and June 2011 were surveyed. The primary outcome was determined using the Treatment Efficacy Questionnaire (TEQ). Electronic medical records were reviewed to determine patient, pain and TPI characteristics. Linear regression was used to determine the predictors of a successful response on the TEQ.
  
  
  RESULTS
  Right upper quadrant was the most common site of AWP, and the median pain duration was 12 months. Pain was rated as >8 (1-10 scale) by 57 % and 30 % described it as an ache. Narcotic use was reported in 38 %, and 73 % had a history of at least one abdominal surgery. Forty-four of the 120 (37 %) patients met the criteria for responder on the TEQ. Compared to before treatment, 36 % reported being "significantly better" and 22 % "slightly better." Multiple linear regression analysis showed that higher somatization negatively predicted response. None of the other historical, examination or TPI characteristics were associated with response to the TPI.
  
  
  CONCLUSIONS
  TPI can provide significant, long-term symptom relief in a third of patients with chronic abdominal pain attributed to AWP. Somatization was inversely related to the treatment success.
authors: Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. alnahhas.firas@gmail.com.
authors: Mhd Firas
authors: MF
authors: Alnahhas
authors: Division of Physical Medicine and Rehabilitation, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. Oxentenko.Shawn@mayo.edu.
authors: Shawn C
authors: SC
authors: Oxentenko
authors: Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. Locke.Giles@mayo.edu.
authors: G Richard
authors: GR
authors: Locke
authors: Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. Hansel.Stephanie@mayo.edu.
authors: Stephanie
authors: S
authors: Hansel
authors: Division of Biomedical Statistics and Informatics, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. schleck@mayo.edu.
authors: Cathy D
authors: CD
authors: Schleck
authors: Division of Biomedical Statistics and Informatics, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. zinsmeis@mayo.edu.
authors: Alan R
authors: AR
authors: Zinsmeister
authors: Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. Farrugia.Gianrico@mayo.edu.
authors: Gianrico
authors: G
authors: Farrugia
authors: Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. grover.madhusudan@mayo.edu.
authors: Madhusudan
authors: http://orcid.org/0000-0001-5092-0831
authors: M
authors: Grover
mesh_terms: D015746:Abdominal Pain / Q000188:drug therapy*; D034861:Abdominal Wall; D001623:Betamethasone / Q000008:administration & dosage / Q000494:pharmacology; D002045:Bupivacaine / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008775:Methylprednisolone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D000077555:Methylprednisolone Acetate; D008875:Middle Aged; D012189:Retrospective Studies; D061028:Trigger Points / Q000473:pathology*
chemical_list: D000077555:Methylprednisolone Acetate; D001623:Betamethasone; D008012:Lidocaine; D008775:Methylprednisolone; D002045:Bupivacaine
keywords: Abdominal wall pain; Chronic abdominal pain; Injection; Ultrasound