Introduction Of A Novel Classification Of Medial Tibial Plateau Fractures Based On Injury Mechanism And Its Clinical Research

Part One Introduction of a novel classification of medial tibial plateau fractures based on injury mechanism and its derived surgical sequenceObjective: Medial tibial plateau fractures usually have worse prognosis due to its high variability and the combination of bony and soft tissue injuries.The aim of this study was to introduce a new classification of medial tibial plateau fractures based on the injury mechanism and evaluate its reliability.The secondary aim was to evaluate the outcomes of operative medial tibial plateau fractures treated according to the surgical sequences which were determined by the new classification.Method: 63 operative medial tibial plateau fractures which were treated following the new surgical sequence were enrolled in our study.CT images of these patients were reviewed and classified twice by four independent observers using Wahlquist classification,Four Quadrants classification and 3D-classification for assessing the reliability.The reliability of the classification was calculated by application of kappa analysis.The surgical sequence determined by 3D-classification was evaluated by observing the the postoperative efficacy during the follow-up.The reduction quality was evaluated according to Rasmussen radiation score and HSS score was used to evaluate the knee function.Result: The intra-observer reliability of 3D-classification showed excellent agreement according to Landis and Koch(The mean k = 0.897,CI 0.806-0.971).And the inter-obsever reliability of IM-classification also showed excellent agreement.(The mean k = 0.883,CI 0.786-0.961).As for comparison of k values(the intra-and inter-obsever)with the other two common classifications,the interobsever k value of 3D classification is higher than that of the other two classifications significantly(P<0.01)and the intraobsever k value of 3D classification is higher than that of Wahlquist classification(P<0.05).All patients were followed up and the average follow-up of the cases was 12.8 months(14-20 months).As for the evaluation of the postoperative efficacy,according to Rasmussen imaging score at 12 months follow-up,23 cases were rated as excellent,38 cases were rated as good and 2 cases were considered as fair results.And according to HSS score of the last follow-up,53 cases were rated as excellent,8 cases were rated as good and 2 cases were considered as fair results.Summary: The new proposed classification showed high intra and inter-observer reliability in our study.And the surgical sequence determined by the classification can help patients to acquire good postoperative efficacy.Therefore the new classification of medial tibial plateau fractures and the accompanied surgical sequence are worthy of further popularization and application in clinical practice.Part Two Single group meta-analysis of the rate of medial tibial plateau fracture with anterior cruciate ligament injuryObjective: Anterior cruciate ligament injury is also considered to be one of the most influential factors for the prognosis of medial tibial plateau fractures.Method: In our study,"tibial plateau fracture" or "medial tibial plateau fracture" and "complications" or "soft tissue injury" or "ligament injury" or "meniscus injury" are the search terms.Computer retrieval of PUBMED,Cochrane Library,Embase,Medline,Chinese CNKI,Wip database,Wanfang database,etc was conducted.The retrieval time was from January,2000 to December,2020.Two independent researchers screened the literature and extracted the data from the included literature with the index of medial tibial plateau fracture complicated with anterior cruciate ligament injury.Single group rate meta-analysis was used to combine the extracted data.The results were meta analyzed by RevMan 5.3 software which was provided by Cochrane Collaboration Network.Result: After screening,there are finally 10 literatures,373 cases in total are included in our study.The results of the meta-analysis showed that the incidence of medial tibial plateau fracture with anterior cruciate ligament injury was 49%(95% CI: 0.46 to 0.52 P<0.001).Summary: Anterior cruciate ligament injuries are common complications of medial tibial plateau fractures,which should be taken seriously.It prompts that orthopedic doctors,especially junior orthopedic doctors,should be alert to the occurrence of anterior cruciate ligament injury when dealing with medial tibial plateau fractures in clinical practice.Part Three The correlational research between 3D-classification of medial tibial plateau fracture and avulsion fracture of anterior cruciate ligamentObjective: The incidence of medial tibial plateau fractures with anterior cruciate ligament injuries is high,and anterior cruciate ligament avulsions are the most common.The purpose of this study is to explore the injury mechanism of the medial tibial plateau fractures associated with ACL avulsions by the correlational research between 3D classification and avulsions fracture of anterior cruciate ligament.Method: The imaging data of 99 patients with medial tibial plateau fractures who were treated in our hospital from January 2015 to December 2020 were selected as subjects of this retrospective study.All cases were numbered and then classified according to 3D-classification.The diagnosis and classification of avulsions of anterior cruciate ligament were performed according to the number.Then we summarized the results of 3D-classification,the results of associated ACL avulsions and the classification of ACL avulsions.Chi square test was used to statistically analyze the incidence of associated ACl avulsions and displaced ACl avulsions among different 3D-classifications.Result: The incidence of associated ACl avulsions and displaced ACl avulsions in flexion-medial tibial plateau fractures was significantly higher than that in extension-medial tibial plateau fracture,and the difference was statistically significant(P<0.05).More ACL avulsions were found in the injury pattern of flexion-valgus than the other injury patterns of the same level(P<0.05).There was no significant difference in the incidence of associated ACl avulsions and displaced ACl avulsions among simple varus-and valusmedial tibial plateau fractures or internal-and external-rotation medial tibial plateau fractures(P>0.05).Summary: This study found that a flexed knee at the occurrence of a medial tibial plateau fracture is a major risk factor for causing associated ACL avulsion or even displaced ACL avulsion.Meanwhile flexion-valus pattern was the main cause of medial tibial plateau fractures associated with ACL avulsions.And tibial rotation was not a significant factor in both producing associated ACL avulsions and affecting the degree of injuries.The findings will help orthopedists understand the injury mechanism of Schatzker type IV tibial plateau fractures associated with ACL avulsions.It can also allow doctors to enhance their awareness of such injuries to avoid unfavorable prognosis.Conclusion: We firstly proposed a new classification of medial tibial plateau fracture based on injury mechanism,namely 3D classification.The new proposed classification showed high intra and inter-observer reliability in our study.And the surgical sequence determined by the classification can help patients to acquire good postoperative efficacy.Therefore the new classification of medial tibial plateau fractures and the accompanied surgical sequence are worthy of further popularization and application in clinical practice.Subsequently,in order to lay the foundation of evidence-based medicine for the further development of accurate treatment strategies for medial tibial plateau fractures,we obtained that the incidence of anterior cruciate ligament injury in medial tibial plateau fractures was 49% through single-group meta-analysis,which deserves attention.Finally,we studied the correlation between 3D classification and avulsion fracture of anterior cruciate ligament.In this part,we found that a flexed knee at the occurrence of a medial tibial plateau fracture is a major risk factor for causing associated ACL avulsion or even displaced ACL avulsion.Meanwhile flexion-valus pattern was the main cause of medial tibial plateau fractures associated with ACL avulsions.And tibial rotation was not a significant factor in both producing associated ACL avulsions and affecting the degree of injuries.The findings will help orthopedists understand the injury mechanism of Schatzker type IV tibial plateau fractures associated with ACL avulsions.It can also allow doctors to enhance their awareness of such injuries to avoid unfavorable prognosis.