title: Adolescent knee pain and patellar dislocations are associated with patellofemoral osteoarthritis in adulthood: A case control study.
abstract: BACKGROUND
  There is a lack of information about the association between patellofemoral osteoarthritis (PFOA) and both adolescent anterior knee pain (AKP) and previous patellar dislocations.
  
  
  METHODS
  This case-control study involved 222 participants from our knee arthroplasty database answering a questionnaire. One hundred and eleven patients suffering from PFOA were 1:1 matched by gender with a unicompartmental tibiofemoral arthritis control group. Multivariate correlation and binary logistic regression analysis were performed, with odds ratios (ORs) and 95% confidence intervals (CIs) calculated.
  
  
  RESULTS
  An individual is 7.5 times more likely to develop PFOA if they have suffered from adolescent AKP (OR 7.5, 95% CIs 1.51 to 36.94). Additionally, experiencing a patellar dislocation increases the likelihood of development of PFOA, with an adjusted odds ratio of 3.2 (95% CIs 1.25 to 8.18). A 44-year difference in median age of first dislocation was also observed between the groups.
  
  
  CONCLUSIONS
  This should bring into question the traditional belief that adolescent anterior knee pain is a benign pathology. Patellar dislocation is also a significant risk factor. These patients merit investigation, we encourage clinical acknowledgement of the potential consequences when encountering patients suffering from anterior knee pain or patellar dislocation.
authors.affiliation: Avon Orthopaedic Centre, Southmead Hospital, Southmead Road, Westbury-on-Trym, Bristol BS10 5NB, UK. Electronic address: henryconchie.2011@my.bristol.ac.uk.
authors.forename: Henry
authors.initials: H
authors.lastname: Conchie
authors.affiliation: Avon Orthopaedic Centre, Southmead Hospital, Southmead Road, Westbury-on-Trym, Bristol BS10 5NB, UK. Electronic address: clarkdamian@hotmail.com.
authors.forename: Damian
authors.initials: D
authors.lastname: Clark
authors.affiliation: Department of Trauma and Orthopaedics, Clinical Trials Unit, Warwick Medical School, Coventry CV4 7AL, UK. Electronic address: a.metcalfe@warwick.ac.uk.
authors.forename: Andrew
authors.initials: A
authors.lastname: Metcalfe
authors.affiliation: Avon Orthopaedic Centre, Southmead Hospital, Southmead Road, Westbury-on-Trym, Bristol BS10 5NB, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Eldridge
authors.affiliation: Avon Orthopaedic Centre, Southmead Hospital, Southmead Road, Westbury-on-Trym, Bristol BS10 5NB, UK; Musculoskeletal Research Unit, Level 1 L&R Building, Southmead Hospital, Southmead Road, Westbury-on-Trym, Bristol BS10 5NB, UK. Electronic address: michael.whitehouse@bristol.ac.uk.
authors.forename: Michael
authors.initials: M
authors.lastname: Whitehouse
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D018771:Arthralgia / Q000150:complications*; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007719:Knee Joint; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000150:complications*; D031222:Patellar Dislocation / Q000150:complications*; D057071:Patellofemoral Joint; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Adolescent; Arthritis; Dislocation; Instability; Patella; Patellofemoral