title: Forced knee extension test is a manual test that correlates with the unstable feelings of patients with ACL injury before and after reconstruction.
abstract: BACKGROUND
  To investigate fear in patients with anterior cruciate ligament (ACL) injury before and after reconstruction, a forced knee extension (FKE) test was performed. The correlation of the test results was evaluated with the subjective function, sports performance and objective parameters.
  
  
  METHODS
  The study included 102 patients with unilateral ACL reconstruction using a semitendinosus tendon with full clinical evaluation. This study was retrospective and determined the longitudinal results of the FKE test and investigated the effects on the subjective and objective outcomes at 2years.
  
  
  RESULTS
  Preoperatively, 47% of patients showed positive FKE tests. The number of positive FKE tests was 31% at six months and 15% at 24months after ACL reconstruction. At two years, there were statistically significant differences between the FKE test positives and negatives regarding both subjective knee recovery (P=0.0095) and sports performance (P=0.0006).
  
  
  CONCLUSIONS
  A new manual test, called the forced knee extension test, for fear in patients with ACL injury before and after reconstruction was introduced. The apprehension remained positive in 15% of the patients two years after ACL reconstruction, which affected subjective recovery of knee function and sports performance.
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan; Department of Orthopaedic Surgery, Suwa Central Hospital, Tokyo, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Shirasawa
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Koga
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Horie
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan.
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Sekiya
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Medical Hospital, Tokyo, Japan. Electronic address: muneta.orj@tmd.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Muneta
mesh_terms: D000070598:Anterior Cruciate Ligament Injuries / Q000175:diagnosis* / Q000523:psychology / Q000601:surgery; D059549:Anterior Cruciate Ligament Reconstruction / Q000523:psychology; D005239:Fear; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000523:psychology / Q000601:surgery; D010808:Physical Examination / Q000379:methods*
keywords: Anterior cruciate ligament injury; Anterior cruciate ligament reconstruction; Apprehension test; Forced knee extension test; Sports performance; Subjective evaluation