title: Procedural intervention for arthrofibrosis after ACL reconstruction: trends over two decades.
abstract: OBJECTIVE
  Arthrofibrosis is a rare complication after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to (1) report a population-based incidence of arthrofibrosis (as defined by manipulation under anaesthesia or surgical lysis of adhesions) following ACL injury and reconstruction, (2) identify risk factors associated with development of arthrofibrosis, and (3) report outcomes of intervention for arthrofibrosis.
  
  
  METHODS
  This was a historical cohort study performed in Olmsted County, Minnesota. The Rochester Epidemiology Project (REP) was used to identify a population-based cohort of individuals with new-onset, isolated ACL tears between 1 January 1990 and 31 December 2010. The REP database provides access to all medical records for each resident of Olmsted County, regardless of the facility where the care was delivered. A total of 1841 individuals were identified with new-onset, isolated ACL tears and were confirmed with chart review. The intervention incidence for arthrofibrosis was then calculated, and various predictive factors including age, sex, calendar year, and meniscal injury were investigated.
  
  
  RESULTS
  During follow-up, 5 patients (1.0 %) in the non-operative cohort and 23 patients (1.7 %) in the ACL reconstruction cohort received intervention for arthrofibrosis, corresponding to an incidence of 0.7 per 1000 person-years in the non-operative cohort and 1.9 per 1000 person-years in the ACL reconstruction cohort. Female patients were 2.5 times more likely to have arthrofibrosis than males. The mean preoperative range of motion was -8° to 83° and improved to a mean of -2° to 127° post-operatively.
  
  
  CONCLUSIONS
  Arthrofibrosis remains a rare but potentially devastating complication after ACL reconstruction, and roughly 2 % of patients had post-operative stiffness that required intervention. Female patients are at higher risk of arthrofibrosis. However, when patients develop severe motion complications after ACL injury, interventions are generally effective in preventing permanent arthrofibrosis.
authors.affiliation: Departments of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. sanders.thomas@mayo.edu.
authors.forename: Thomas L
authors.identifier: http://orcid.org/0000-0001-7741-9692
authors.initials: TL
authors.lastname: Sanders
authors.affiliation: Departments of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.|Health Sciences Research, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Hilal Maradit
authors.initials: HM
authors.lastname: Kremers
authors.affiliation: Departments of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Bryan
authors.affiliation: Health Sciences Research, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Walter K
authors.initials: WK
authors.lastname: Kremers
authors.affiliation: Departments of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Stuart
authors.affiliation: Departments of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Krych
mesh_terms: D000328:Adult; D059549:Anterior Cruciate Ligament Reconstruction / Q000009:adverse effects*; D001182:Arthroscopy; D015331:Cohort Studies; D005260:Female; D005355:Fibrosis; D006801:Humans; D007719:Knee Joint / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008349:Manipulation, Orthopedic; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D012737:Sex Factors
keywords: ACL Injury; ACL reconstruction; Arthrofibrosis; Lysis of adhesions; Manipulation; Procedural Intervention