title: Risk Factors Associated With Grade 3 Pivot Shift After Acute Anterior Cruciate Ligament Injuries.
abstract: BACKGROUND
  Recent literature has demonstrated that involvement in pivoting sports at the time of injury, increased posterior-inferior tibial slope (PITS), anterolateral capsular ligament (ALCL) disruptions, and combined lateral meniscal lesions all contribute to a higher grade of pivot shift after acute anterior cruciate ligament (ACL) injuries.
  
  
  OBJECTIVE
  To identify risk factors associated with grade 3 pivot shift after acute ACL injuries.
  
  
  METHODS
  Case-control study; Level of evidence, 3.
  
  
  METHODS
  A database of patients undergoing primary ACL reconstruction from 2009 to 2015 after acute ACL injuries was retrospectively reviewed. A total of 30 patients (30 knees) with grade 3 pivot shift were identified as the study group. Moreover, 30 patients (30 knees) with grade 1 and 30 patients (30 knees) with grade 2 pivot shift were randomly chosen as the 2 control groups. All pivot-shift tests were performed with the patients under anesthesia. Predictors of grade 3 pivot shift that were explored included patient age, sex, time from injury to surgery, pivoting sports involvement at the time of injury, lateral PITS, medial PITS, ALCL disruptions, preoperative KT-1000 arthrometer side-to-side difference, and combined lateral or medial meniscal lesions. Comparisons were performed between the study group and the 2 control groups. Univariable and multivariable logistic regressions were used to identify independent risk factors that were associated with grade 3 pivot shift.
  
  
  RESULTS
  Univariable and multivariable logistic regressions between the study group and the 2 control groups showed that pivoting sports involvement at the time of injury (odds ratio1 [OR1; grade 3 vs grade 1 pivot shift with grade 1 = reference], 11.88; 95% CI, 1.94-149.91; OR2 [grade 3 vs grade 2 pivot shift with grade 2 = reference], 3.41; 95% CI, 1.92-22.60), abnormal degree of lateral PITS (OR1, 14.41; 95% CI, 1.69-174.78; OR2, 6.41; 95% CI, 1.48-47.70), ALCL disruptions (OR1, 8.28; 95% CI, 1.71-117.14; OR2, 4.96; 95% CI, 1.07-28.75), and combined lateral meniscal lesions (OR1, 27.56; 95% CI, 5.48-240.52; OR2, 5.83; 95% CI, 1.21-38.56) were independent risk factors of grade 3 pivot shift after acute ACL injuries.
  
  
  CONCLUSIONS
  For acute ACL injuries, the best set of predictors of grade 3 pivot shift were pivoting sports involvement at the time of injury, abnormal lateral PITS, ALCL disruptions, and combined lateral meniscal lesions. These results may provide additional information for counseling patients on residual laxity and risks for graft rerupture after ACL reconstruction.
authors.affiliation: Sports Medicine Service, Beijing Jishuitan Hospital, Beijing, China.
authors.forename: Guan-yang
authors.initials: GY
authors.lastname: Song
authors.affiliation: Sports Medicine Service, Beijing Jishuitan Hospital, Beijing, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Clinical Research and Evidence-Based Medicine Center, Beijing Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Beijing, China.
authors.forename: Qian-qian
authors.initials: QQ
authors.lastname: Wang
authors.affiliation: Sports Medicine Service, Beijing Jishuitan Hospital, Beijing, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Sports Medicine Service, Beijing Jishuitan Hospital, Beijing, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.affiliation: Sports Medicine Service, Beijing Jishuitan Hospital, Beijing, China fenghua20080617@126.com.
authors.forename: Hua
authors.initials: H
authors.lastname: Feng
mesh_terms: D000208:Acute Disease; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000503:physiopathology; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology* / Q000601:surgery; D007718:Knee Injuries / Q000503:physiopathology* / Q000601:surgery; D016015:Logistic Models; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
keywords: acute anterior cruciate ligament injury; grade 3 pivot shift; risk factor