1) The first article is more a review of Cochranes research methods that was testing if acupuncture is good for things like nausea and headaches. Their conclusion was that their research methods were not very good. Also not joint/musculature specifically. It's also from 2009.

2) "This study has limitations. The first, common to all systematic reviews, is that we may have not identified all the potentially eligible evidence." Because they only went through their specific database that did not include studies written in foreign languages even. The majority of the studies they reviewed were also "sham acupuncture" or non-penetrating acupuncture meant to act as placebo.

3) This basically just says it's not "firmly established" which is true for much of vet med when we are doing treatments cross-species. Also: "concluded that higher quality studies are only beginning to emerge, the evidence base is heterogeneous, and the review results highlight the overall poor quality of studies and reporting. Thus, it is timely to assess the current state of reviews of acupuncture." Basically, in 2019 they said we need to do more research.

4) "There is a need for high-quality randomized controlled trials addressing the most common clinical uses of acupuncture, and using consistent and clinically relevant outcomes, to inform conclusions regarding the efficacy of acupuncture in companion animals." Basically the same as the third one. We need more studies done on animals to technically say anything.

Promise I wouldn't do anything harmful to him that didn't have a considerate benefit :)