Ultrasound Guided Transversus Abdominis Plane (TAP) vs. Trigger Point Injection (TPI) for Abdominal Wall Pain
Ultrasound Guided Transversus Abdominis Plane (TAP) vs. Trigger Point Injection (TPI) for Abdominal Wall Pain
Patients with chronic abdominal pain- with a component of abdominal wall pain- are often
 treated with trigger point injections. This study will help to determine if a block within
 the transversus abdominis plane (TAP) will provide superior analgesic benefit to a trigger
 point injection as therapy for these patients.
Only patients referred to the Pain Clinic for abdominal trigger point injections for
 abdominal wall pain will be considered for study recruitment.

 Following informed consent, patients will complete a baseline questionnaire in the Pain
 Clinic which gathers basic demographic data, pain scores and functional scores. Patients will
 be randomized to receive either a TAP injection or a TPI. Because the TAP injection involves
 a larger area to be anesthetized, a larger volume of medication will be used.

 Thirty minutes after the injection, a sensory exam will be performed on the patient to
 determine the level of block. At one week, one month, three months and six months after the
 injection, a staff member will telephone the patient to assess how they are doing. The call
 will take approximately 10 minutes and will consist of relaying a pain score as well as daily
 functioning and sleep questions.

 Subjects are responsible for all clinical costs associated with the injection.

 There is no remuneration offered for study participation.
Inclusion Criteria:

 Only patients referred to Pain Clinic for a trigger point injection.

 -  Non-cancer pain greater than 3 months duration.

 -  Unilateral abdominal pain.

 -  Positive Carnett's sign (A test in which acute abdominal pain remains unchanged or
 increases when the muscles of the abdominal wall are tensed.)

 -  An identifiable abdominal trigger point.

 Exclusion Criteria:

 -  History of chronic psychotic disorder.

 -  History of dementing illness.

 -  Active abdominal visceral disease as a known contributor of the pain.

 -  Abdominal surgery in the past 6 months.

 -  More than one trigger point.

 -  Abdominal wall hernias.

 -  BMI>40.