It doesn’t really matter how you manipulate the spine

SKEPTICS: Spinal manipulation is a big ol’ nothing burger.

SPINAL ADJUSTMENT FANS: It’s all in the wrist. Got to do it right. You just suck at it.

BIG NEW SCIENTIFIC REVIEW: Nope, doesn’t matter how you manipulate the spine. “None of the SMT procedures were superior to others in terms of pain relief.”

Sooo much energy has been poured into spinal manipulation “technique” over the years … without much to show for it. Nim et al is now the go-to citation for “it does not matter how you do it.” This contributes strongly to the broader point that spinal manipulative therapy is still not evidence-based medicine, and not for lack of trying.

This topic is always controversial. When I shared this paper on social media, a popular soft criticism was that it gives us a non-conclusion, rather than an actual strike against manipulation, because it was based on low-quality evidence only. But that’s not strictly the same as an absence-of-evidence …

It is reasonable to infer evidence-of-absence from a posse of junky little studies that fail to produce a signal even when biased, even when many of the researchers are almost certainly trying to p-hack their way to a happy ending. Is that inference as good as a high quality RCT that “proves” that manipulation technique is trivial or completely irrelevant? Of course not. But it’s also not nothing! It’s informative when a bunch of high-risk-of-bias trials cannot even cough up a convincing false positive, let alone the real deal.

If it’s really hard to detect the difference made by manipulation technique, it’s probably because it just doesn’t exist.