This study evaluated the validity and informational value of TikTok videos related to the anterior cruciate ligament (ACL). A total of 100 videos were analyzed, with 420 initially retrieved using the keywords "anterior cruciate ligament" and "ACL." The videos were categorized by source (private user, physical therapist, surgeon, researcher), subject type (patient experience, physical therapy, injury mechanism, anatomy, clinical test, surgical technique), content (patient experience/testimony, education, rehabilitation), and background audio (music or voice). Video quality was assessed using the DISCERN instrument, the Journal of the American Medical Association (JAMA) benchmark criteria, and the Global Quality Score (GQS). The mean DISCERN, JAMA, and GQS scores were 15.73 ± 1.44, 0.19 ± 0.39, and 1.16 ± 0.37, respectively, indicating poor quality on all three indices. The number of views, likes, shares, comments, and video lengths were all positively correlated with DISCERN, JAMA, and GQS scores. A significant difference was found in DISCERN scores between videos by private users and those by surgeons. The study concluded that the educational value of these videos on the ACL is poor. Given the rapid growth of TikTok, further research is needed. The study highlights the need for caution when relying on TikTok videos for medical information, as they may not provide adequate or valid information. The findings suggest that while TikTok is a popular platform for sharing information, the quality of medical content, particularly regarding the ACL, is generally poor. This has implications for patients seeking information on ACL injuries and treatments, as they may be exposed to inaccurate or unreliable content. The study also emphasizes the importance of developing better tools and methods for assessing the quality of medical content on social media platforms.This study evaluated the validity and informational value of TikTok videos related to the anterior cruciate ligament (ACL). A total of 100 videos were analyzed, with 420 initially retrieved using the keywords "anterior cruciate ligament" and "ACL." The videos were categorized by source (private user, physical therapist, surgeon, researcher), subject type (patient experience, physical therapy, injury mechanism, anatomy, clinical test, surgical technique), content (patient experience/testimony, education, rehabilitation), and background audio (music or voice). Video quality was assessed using the DISCERN instrument, the Journal of the American Medical Association (JAMA) benchmark criteria, and the Global Quality Score (GQS). The mean DISCERN, JAMA, and GQS scores were 15.73 ± 1.44, 0.19 ± 0.39, and 1.16 ± 0.37, respectively, indicating poor quality on all three indices. The number of views, likes, shares, comments, and video lengths were all positively correlated with DISCERN, JAMA, and GQS scores. A significant difference was found in DISCERN scores between videos by private users and those by surgeons. The study concluded that the educational value of these videos on the ACL is poor. Given the rapid growth of TikTok, further research is needed. The study highlights the need for caution when relying on TikTok videos for medical information, as they may not provide adequate or valid information. The findings suggest that while TikTok is a popular platform for sharing information, the quality of medical content, particularly regarding the ACL, is generally poor. This has implications for patients seeking information on ACL injuries and treatments, as they may be exposed to inaccurate or unreliable content. The study also emphasizes the importance of developing better tools and methods for assessing the quality of medical content on social media platforms.