Multisite Pilot of Chiropractic for
Chronic Pelvic Pain
Progress Report

This section was compiled by Frank M. Painter, D.C.
Send all comments or additions to:   Frankp@chiro.org

Cheryl Hawk, DC, PhD ¹; Cynthia Long, PhD ¹; Robert Reiter, MD ²; Charles Davis, PhD ³; Jerrilyn Backman, DC, MPH ⁴; Roni Evans, DC <sup>5

1</sup> Palmer Center for Chiropractic Research
² University of Iowa Hospitals and Clinics
³ University of Iowa College Public Health, Department of Biostatistics
⁴ National College of Chiropractic
⁵ Northwestern Health Sciences University

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Background and Objective:   Chronic pelvic pain (CPP) in women, defined as noncyclic pain in the pelvis persisting at least six months, causes significant pain, disability and consumption of health care services. Its prevalence among women in the U.S. is estimated at 14.7%, and it accounts annually for 10-15% of hysterectomies and 40% of laparoscopies. Annual cost of outpatient care for CPP is estimated at $2.8 billion, excluding surgery and hospitalization; lost work days cost an additional $555.3 million. CPP is often unresponsive to traditional medical management and may be appropriate for investigation of complementary therapies like chiropractic. The proposed study is a pilot for a multisite randomized clinical trial. The purpose of the pilot was to test the recruitment and study protocols for the RCT.

Method:   This was a pilot study for a multisite randomized placebo-controlled clinical trial of chiropractic care for women with chronic pelvic pain, conducted at three chiropractic college research clinics with a targeted sample size of 60 (20 per site) The study group received six weeks of chiropractic treatment (Flexion-Distraction and manual Trigger Point Therapy techniques), and the control group received sham chiropractic manipulation combined with light massage. The primary outcome measure was the change in the Pain Disability Index (PDI) from baseline to six weeks. Eligibility criteria were as follows:

Inclusion:
1. Females ages 18-45;
2. Diagnosis of CPP by each site’s screening gynecologist;
3. Naive to chiropractic manipulation, defined as not having been under chiropractic care for the past year; and never for the treatment of pelvic pain (by patient report).

Exclusion:
1. Pregnancy;
2. Menopause, defined as cessation of menstrual periods for at least the preceding six months;
3. Reproductive tract surgery within the past six months;
4. Presence of pathology or other health conditions requiring medical treatment and/or presenting a contraindication to chiropractic treatment, as determined by the screening gynecologist;
5. Other contraindications to manipulation, such as presence of fracture or certain structural abnormalities;
6. Absence of indications of musculoskeletal dysfunction, as determined by the chiropractic clinician;
7. Litigation for a health-related claim (in process or pending); and
8. Under treatment, medical or other, currently for conditions other than CPP, excluding counseling or psychotherapy.

Results:   Of 355 phone calls at all three sites, 322 completed the phone screening. At this point, 152 were eligible to continue the screening process; of the 169 ineligible, 109 were ineligible due to chiropractic experience within the last year. Only 82 of the eligible callers actually reported for the on-site face-to-face screening. Seventy-three were eligible after face-to-face screening, and all 73 remained eligible after the chiropractic screening examination. Due to scheduling difficulties with the gynecologists, only 48 potential patients completed the gynecological screening; six of these were found ineligible. A total of 39 patients were enrolled in the study (three eligible patients declined to participate). Of these 39 patients, 20 were randomized to the active group and 19 to the placebo group. Mean ages were 34.7 (SD=7.6) for the active group and 33.7 (SD=7.6) for the placebo group. The median reported duration of CPP symptoms was 7.5 years (range 1-31) for the active group and 7.0 years (range 1-22) for the placebo group. The PDI, on a scale of 0-70, had a median score of 19.5 (range 2-36) at baseline for the active group and 19.0 (range 2-65) for the placebo group. Perception of treatment group assignment in both groups was correct in about half the patients at each site. Data analysis of the PDI scores is still in progress.

CONCLUSION:   Although data analysis is not yet complete, results at this point suggest that:
1) recruitment of adequate sample size for the projected trial is not feasible at the three sites involved in the pilot, given the current eligibility criteria, particularly the restriction of previous chiropractic experience;
2) methods of standardization of the application of the manual procedures is an extremely important issue for the future planned RCT;
3) patient blinding appears to be successful, using the current treatment and placebo protocols.

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