To summarize changes in recommendations for injection treatments for knee osteoarthritis (OA) in current clinical practice guidelines (CPGs) and to assess whether these changes have affected public interest according to Google data and content in YouTube videos. A literature search to identify CPGs revised since 2019 that provide recommendations regarding the five intra-articular injection treatments for knee OA (corticosteroid CS, hyaluronic acid HA, stem cell SC, platelet-rich plasma PRP, and botulinum toxin BT) was conducted to assess perspective changes for each treatment. Data from Google Trends were examined to identify changes in search volume from 2004 to 2021 using a join-point regression model. Relevant YouTube videos were divided into those uploaded before and after changes in CPGs and compared according to degrees of recommendation for each treatment to identify the effect of changes in CPGs on video production. All eight identified CPGs released after 2019 recommended HA and CS use. Most CPGs were the first to state a neutral or opposing stance concerning the use of SC, PRP, or BT. Interestingly, relative searches on Google for SC, PRP, and BT has increased greater than those for CS and HA. YouTube videos produced after CPGs changed continue to recommend SC, PRP, and BT as much as those produced before CPGs were revised. Although knee OA CPGs have changed, public interest and healthcare information providers on YouTube have not reacted to this shift. Improved methods to propagate updates to CPGs warrant consideration.