OBJECTIVE:The optimal non-surgical therapy for chronic ankle instability remains unclear due to the continuous introduction of novel treatment methods despite the availability of several non-surgical options for improving foot and ankle function and dynamic balance in chronic ankle instability patients.This study aims to investigate the most effective non-surgical therapy options to improve foot and ankle function and dynamic balance for patients with chronic ankle instability using a network meta-analysis. METHODS:Using"CAI,exercise,and randomized controlled trial"as search terms,a literature search of PubMed,Embase,Cochrane Library,and Web of Science databases was conducted through a computer network to collect information from the databases from their inception to March 2024 on non-surgical therapies for the treatment of chronic ankle instability randomized controlled trials on foot and ankle function or dynamic balance in patients.EndNote software was utilized for literature management.RevMan 5.4 software and Cochrane Risk of Bias Assessment Tool were used to evaluate the risk of bias of the included literature.Paired meta-analysis and network meta-analysis of the outcomes such as the Foot and Ankle Ability Measure in daily living subscale score,Foot and Ankle Ability Measure in sports activities subscale score,Star Excursion Balance Test-Anterior score,Star Excursion Balance Test-Posteromedial score,Star Excursion Balance Test-Posterolateral score and Cumberland ankle instability tool score were performed using the network commands of Stata 14.0 software.The strength of evidence rating of the outcome metrics was evaluated according to the GRADE Level of Evidence and Strength of Recommendation Grading Criteria. RESULTS:Of the 22 randomized controlled trials that met the inclusion criteria,1 study was rated as low risk,8 studies were rated as medium risk,and 13 studies were rated as high risk,enrolling a total of 952 patients and 25 treatments.(1)Network meta-analysis showed that compared with the control group,Isokinetic Strength Training,Balance Training,Balance+Stroboscopic Glasses Training,Strength Training,Joint Mobilizations Training,CrossFit Training,CrossFit Training+Self-Mobilization,Wobble Board Training,National Academy of Sport Medicine corrective exercise program,Trigger Point Dry Needling,and Neuromuscular Training had different significant enhancement effects on improving foot and ankle function and dynamic balance in patients with chronic ankle instability(P<0.05).(2)Cumulative probability ranking results showed that the three treatments with the highest ranked Cumberland ankle instability tool score were Joint Mobilizations Training(88.6%)>Visual Feedback Balance Training(83.1%)>CrossFit Training+Self-Mobilization(74.8%);the three treatments with the highest ranked Star Excursion Balance Test-Anterior score were Joint Mobilizations Training(88.4%)>Isokinetic Strength Training(86.9%)>National Academy of Sport Medicine corrective exercise program(65.0%);the three treatments with the highest ranked Star Excursion Balance Test-Posteromedial score were Balance+Stroboscopic Glasses Training(87.4%)>Neuromuscular Training(74.6%)>Strength Training(68.9%);the three treatments with the highest ranked Star Excursion Balance Test-Posterolateral score were CrossFit Training+Self-Mobilization(74.6%)>Balance+Stroboscopic Glasses Training(70.0%)>Neuromuscular Training(63.7%);the three treatments with the highest ranked Foot and Ankle Ability Measure in daily living subscale score were National Academy of Sport Medicine corrective exercise program(91.9%)>Balance+Stroboscopic Glasses Training(85.6%)>Wobble Board Training(82.2%);the three treatments with the highest ranked Foot and Ankle Ability Measure in sports activities subscale score were Balance+Stroboscopic Glasses Training(93.5%)>Balance Training(86.7%)>National Academy of Sport Medicine corrective exercise program(86.4%). CONCLUSION:Non-surgical therapies can significantly improve foot and ankle function and dynamic balance in patients with chronic ankle instability.National Academy of Sport Medicine corrective exercise program had the best efficacy in improving foot and ankle daily activity function in chronic ankle instability patients;Balance+Stroboscopic Glasses Training had the best efficacy in improving foot and ankle sports function and posterior medial dynamic balance;Joint Mobilizations Training had the best efficacy in improving anterolateral dynamic balance and ankle instability condition;and CrossFit Training+Self-Mobilization had the best efficacy in improving posterior lateral dynamic balance.The strength of evidence for each outcome was low,influenced by the risk of methodological bias and risk of publication bias of the included studies.Therefore,the above conclusions need to be validated by more high-quality pilot studies.