This systematic review and meta-analysis evaluates the risk factors for secondary anterior cruciate ligament (ACL) injuries in younger athletes after ACL reconstruction (ACLR). The study aims to provide a comprehensive synthesis of the literature on age and activity level as primary risk factors for reinjury. The review includes 19 articles from databases such as PubMed and EBSCO host, focusing on studies that report reinjury rates in younger populations. The overall total second ACL reinjury rate was found to be 15%, with an ipsilateral reinjury rate of 7% and a contralateral injury rate of 8%. The secondary ACL injury rate (ipsilateral + contralateral) for patients younger than 25 years was 21%. Athletes who return to sports have a secondary ACL injury rate of 20%, and combining these factors results in a rate of 23% for athletes younger than 25 years who return to sports. The review highlights that younger age and a return to high-level activity are significant risk factors for secondary ACL injuries, with nearly 1 in 4 young athletic patients sustaining another ACL injury after returning to high-risk sports. The high rate of secondary injuries in young athletes who return to sport after ACLR suggests a 30 to 40 times greater risk compared to uninjured adolescents. The review also discusses the potential benefits of activity modification, improved rehabilitation, and integrative neuromuscular training to reduce the risk of secondary ACL injuries.This systematic review and meta-analysis evaluates the risk factors for secondary anterior cruciate ligament (ACL) injuries in younger athletes after ACL reconstruction (ACLR). The study aims to provide a comprehensive synthesis of the literature on age and activity level as primary risk factors for reinjury. The review includes 19 articles from databases such as PubMed and EBSCO host, focusing on studies that report reinjury rates in younger populations. The overall total second ACL reinjury rate was found to be 15%, with an ipsilateral reinjury rate of 7% and a contralateral injury rate of 8%. The secondary ACL injury rate (ipsilateral + contralateral) for patients younger than 25 years was 21%. Athletes who return to sports have a secondary ACL injury rate of 20%, and combining these factors results in a rate of 23% for athletes younger than 25 years who return to sports. The review highlights that younger age and a return to high-level activity are significant risk factors for secondary ACL injuries, with nearly 1 in 4 young athletic patients sustaining another ACL injury after returning to high-risk sports. The high rate of secondary injuries in young athletes who return to sport after ACLR suggests a 30 to 40 times greater risk compared to uninjured adolescents. The review also discusses the potential benefits of activity modification, improved rehabilitation, and integrative neuromuscular training to reduce the risk of secondary ACL injuries.