title: Meniscus treatment and age associated with narrower radiographic joint space width 2-3 years after ACL reconstruction: data from the MOON onsite cohort.
abstract: OBJECTIVE
  To identify risk factors for radiographic signs of post-traumatic osteoarthritis (OA) 2-3 years after anterior cruciate ligament (ACL) reconstruction through multivariable analysis of minimum joint space width (mJSW) differences in a specially designed nested cohort.
  
  
  METHODS
  A nested cohort within the Multicenter Orthopaedic Outcomes Network (MOON) cohort included 262 patients (148 females, average age 20) injured in sport who underwent ACL reconstruction in a previously uninjured knee, were 35 or younger, and did not have ACL revision or contralateral knee surgery. mJSW on semi-flexed radiographs was measured in the medial compartment using a validated computerized method. A multivariable generalized linear model was constructed to assess mJSW difference between the ACL reconstructed and contralateral control knees while adjusting for potential confounding factors.
  
  
  RESULTS
  Unexpectedly, we found the mean mJSW was 0.35 mm wider in ACL reconstructed than in control knees (5.06 mm (95% CI 4.96-5.15 mm) vs 4.71 mm (95% CI 4.62-4.80 mm), P < 0.001). However, ACL reconstructed knees with meniscectomy had narrower mJSW compared to contralateral normal knees by 0.64 mm (95% C.I. 0.38-0.90 mm) (P < 0.001). Age (P < 0.001) and meniscus repair (P = 0.001) were also significantly associated with mJSW difference.
  
  
  CONCLUSIONS
  Semi-flexed radiographs can detect differences in mJSW between ACL reconstructed and contralateral normal knees 2-3 years following ACL reconstruction, and the unexpected wider mJSW in ACL reconstructed knees may represent the earliest manifestation of post-traumatic osteoarthritis and warrants further study.
authors.affiliation: Cleveland Clinic, USA. Electronic address: jonesm7@ccf.org.
authors.forename: M H
authors.initials: MH
authors.lastname: Jones
authors.affiliation: Cleveland Clinic, USA; Vanderbilt University Medical Center, USA. Electronic address: spindlk@ccf.org.
authors.forename: K P
authors.initials: KP
authors.lastname: Spindler
authors.affiliation: Brown University/Rhode Island Hospital, USA. Electronic address: braden_fleming@brown.edu.
authors.forename: B C
authors.initials: BC
authors.lastname: Fleming
authors.affiliation: Brigham and Women's Hospital/Harvard Medical School, USA. Electronic address: duryea@bwh.harvard.edu.
authors.forename: J
authors.initials: J
authors.lastname: Duryea
authors.affiliation: Cleveland Clinic, USA. Electronic address: obuchon@ccf.org.
authors.forename: N A
authors.initials: NA
authors.lastname: Obuchowski
authors.affiliation: Vanderbilt University Medical Center, USA. Electronic address: erica.a.scaramuzza@vanderbilt.edu.
authors.forename: E A
authors.initials: EA
authors.lastname: Scaramuzza
authors.affiliation: Steamboat Physical Therapy, Inc, USA. Electronic address: hoksendahl@yahoo.com.
authors.forename: H L
authors.initials: HL
authors.lastname: Oksendahl
authors.affiliation: Cleveland Clinic, USA. Electronic address: winalsc@ccf.org.
authors.forename: C S
authors.initials: CS
authors.lastname: Winalski
authors.affiliation: Vanderbilt University Medical Center, USA. Electronic address: carol.l.duong@vanderbilt.edu.
authors.forename: C L
authors.initials: CL
authors.lastname: Duong
authors.affiliation: Vanderbilt University Medical Center, USA. Electronic address: laura.huston@vanderbilt.edu.
authors.forename: L J
authors.initials: LJ
authors.lastname: Huston
authors.affiliation: Cleveland Clinic, USA. Electronic address: parkerr@ccf.org.
authors.forename: R D
authors.initials: RD
authors.lastname: Parker
authors.affiliation: The Ohio State University Wexner Medical Center, USA. Electronic address: christopher.kaeding@osumc.edu.
authors.forename: C C
authors.initials: CC
authors.lastname: Kaeding
authors.affiliation: Cleveland Clinic, USA. Electronic address: andrisj@ccf.org.
authors.forename: J T
authors.initials: JT
authors.lastname: Andrish
authors.affiliation: The Ohio State University Wexner Medical Center, USA. Electronic address: david.flanigan@osumc.edu.
authors.forename: D C
authors.initials: DC
authors.lastname: Flanigan
authors.affiliation: University of Wisconsin School of Medicine and Public Health, USA. Electronic address: dunn@ortho.wisc.edu.
authors.forename: W R
authors.initials: WR
authors.lastname: Dunn
authors.affiliation: Vanderbilt University Medical Center, USA. Electronic address: emily.reinke@vanderbilt.edu.
authors.forename: E K
authors.initials: EK
authors.lastname: Reinke
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D059549:Anterior Cruciate Ligament Reconstruction; D001265:Athletic Injuries / Q000150:complications / Q000601:surgery*; D002648:Child; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000150:complications / Q000601:surgery*; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000601:surgery; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008592:Menisci, Tibial / Q000000981:diagnostic imaging / Q000601:surgery*; D020370:Osteoarthritis, Knee / Q000453:epidemiology; D011859:Radiography; D012307:Risk Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: ACL reconstruction; Joint space narrowing; Knee; Meniscus; Post-traumatic osteoarthritis; Radiographs