Spinal manipulation for primary and secondary dysmenorrhoea? No!!!

Dysmenorrhoea refers to the occurrence of painful menstrual cramps of uterine origin and is a common gynaecological condition. The efficacy of medical treatments such as nonsteroidal anti-inflammatories (NSAIDs) or oral contraceptive pills (OCPs) is considerable. However the failure rate can still be as high as 20-25% and there are also a number of associated adverse effects. Many women are thus seeking alternatives to conventional medicine. One popular treatment modality is spinal manipulation.

The objectives of this Cochrane review were to determine the safety and efficacy of spinal manipulations for the treatment of primary or secondary dysmenorrhoea when compared to:

• each other,
• placebo,
• no treatment,
• or other medical treatments.

Electronic searches of the Cochrane Menstrual Disorders and Subfertility Group specialised register of controlled trials, CCTR, MEDLINE, EMBASE, CINAHL, Bio extracts, Psyclit and SPORTDiscus were performed to identify relevant randomised controlled trials (RCTs). The Cochrane Complementary Medicine Field’s Register of controlled trials (CISCOM) was also searched. Attempts were also made to identify trials from the National Research Register, the Clinical Trial Register and the citation lists of review articles and included trials. In most cases, the first or corresponding author of each included trial was contacted for additional information.

Included were any RCTs including spinal manipulative interventions (e.g. chiropractic, osteopathy or manipulative physiotherapy) vs each other, placebo, no treatment, or other medical treatment were considered. Exclusion criteria were: mild or infrequent dysmenorrhoea or dysmenorrhoea from an IUD.

Five RCTs were identified that fulfilled the inclusion criteria for this review. Four trials involving high velocity, low amplitude manipulation (HVLA), and one involving the Toftness manipulation technique were included. Quality assessment and data extraction were performed independently by two reviewers. Meta analysis was performed using odds ratios for dichotomous outcomes and weighted mean differences for continuous outcomes. Data unsuitable for meta-analysis were reported as descriptive data and were also included for discussion. The outcome measures were pain relief or pain intensity (dichotomous, visual analogue scales, descriptive) and adverse effects.

Results from the four trials of high velocity, low amplitude manipulation suggest that the technique was no more effective than sham manipulation for the treatment of dysmenorrhoea, although it was possibly more effective than no treatment. Three of the smaller trials indicated a difference in favour of HVLA, however, the only trial with an adequate sample size found no difference between HVLA and sham treatment. There was no difference in adverse effects experienced by participants in the HVLA or sham treatment. The Toftness technique was shown to be more effective than sham treatment by one small trial, but no strong conclusions could be made due to the small size of the trial and other methodological considerations.

The authors concluded that overall there is no evidence to suggest that spinal manipulation is effective in the treatment of primary and secondary dysmenorrhoea. There is no greater risk of adverse effects with spinal manipulation than there is with sham manipulation.

Probably the first question that springs in one’s mind is, WHY ON EARTH COULD SPINAL MANIPULATIONS BE EFFECTIVE FOR THIS CONDITION? Unsurprisingly, the proponents of this approach have come up with several rationales:

• The parasympathetic and sympathetic pelvic nerve pathways are closely associated with the spinal vertebrae, in particular the 2nd-4th sacral segments and the 10th thoracic to the 2nd lumbar segments. One hypothesis is that mechanical dysfunction in these vertebrae causes decreased spinal mobility. This could affect the sympathetic nerve supply to the blood vessels supplying the pelvic viscera, leading to dysmenorrhoea as a result of vasoconstriction. Manipulation of these vertebrae increases spinal mobility and may improve pelvic blood supply through an influence on the autonomic nerve supply to the blood vessels.
• Another hypothesis is that dysmenorrhoea is referred pain arising from musculoskeletal structures that share the same pelvic nerve pathways. The character of pain from musculoskeletal dysfunction can be very similar to gynecological pain and can present as cyclic pain as it can also be altered by hormonal influences associated with menstruation.

I think we can all agree that these theories are very long shots! As it stands, we also do not need to shoot long at all. There is simply no good evidence that spinal manipulations work for dysmenorrhoea. There is thus no need to embark on implausible explanations to justify the notions of Palmer and Still  claiming that spinal manipulation is a panacea. The idiocy of this claim has long been established.

The only question that does remain, in my view, is this:

WHEN WILL CHIROPRACTORS AND OSTEOPATHS FINALLY GIVE UP THEIR OUTLANDISHLY WISHFUL THINKING OF THEIR FOUNDING FATHERS?