title: Cross-sectional and Longitudinal Associations between Knee Joint Effusion Synovitis and Knee Pain in Older Adults.
abstract: OBJECTIVE
  To describe the cross-sectional and longitudinal associations between knee regional effusion synovitis and knee pain in older adults.
  
  
  METHODS
  Data from a population-based random sample (n = 880, mean age 62 yrs, 50% women) were used. Baseline knee joint effusion synovitis was graded (0-3) using T2-weighted magnetic resonance imaging (MRI) in the suprapatellar pouch, central portion, posterior femoral recess, and subpopliteal recess. Effusion synovitis of the whole joint was defined as a score of ≥ 2 in any subregion. Other knee structural (including cartilage, bone marrow, and menisci) lesions were assessed by MRI at baseline. Knee pain was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire at baseline and 2.6 years later. Multivariable analyses were performed after adjustment for age, sex, body mass index, and other structural lesions.
  
  
  RESULTS
  The prevalence of effusion synovitis was 67%. Suprapatellar pouch effusion synovitis was significantly and independently associated with increased total and nonweight-bearing knee pain in both cross-sectional and longitudinal analyses (for an increase in total knee pain of ≥ 5, RR 1.26 per grade, 95% CI 1.04-1.52), and increased weight-bearing knee pain in longitudinal analysis only. Effusion synovitis in posterior femoral recess and central portion were independently associated with increases in nonweight-bearing pain (RR 1.63 per grade, 95% CI 1.32-2.01 and RR 1.29 per grade, 95% CI 1.01-1.65, respectively) in longitudinal analyses only.
  
  
  CONCLUSIONS
  Knee joint effusion synovitis has independent associations with knee pain in older adults. Suprapatellar pouch effusion synovitis is associated with nonweight-bearing and weight-bearing knee pain, while posterior femoral recess and central portion effusion synovitis are only associated with nonweight-bearing pain.
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Xia
authors.initials: X
authors.lastname: Wang
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Xingzhong
authors.initials: X
authors.lastname: Jin
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Weiyu
authors.initials: W
authors.lastname: Han
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Yuelong
authors.initials: Y
authors.lastname: Cao
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Andrew
authors.initials: A
authors.lastname: Halliday
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Leigh
authors.initials: L
authors.lastname: Blizzard
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Faming
authors.initials: F
authors.lastname: Pan
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Benny
authors.initials: B
authors.lastname: Antony
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Flavia
authors.initials: F
authors.lastname: Cicuttini
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Graeme
authors.initials: G
authors.lastname: Jones
authors.affiliation: From the Menzies Institute for Medical Research, University of Tasmania; Department of Radiology, Royal Hobart Hospital, Hobart, Australia; Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia; Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University, Guangzhou, China; Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Epidemiology and Biostatistics, School of Public Health, and the Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, China.X. Wang, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; X. Jin, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; W. Han, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Orthopedics, 3rd Affiliated Hospital of Southern Medical University; Y. Cao, MD, Menzies Institute for Medical Research, University of Tasmania, and Research Institute of Orthopedics, Shuguang Hospital, Shanghai University of Traditional Chinese Medicine; A. Halliday, MD, Department of Radiology, Royal Hobart Hospital; L. Blizzard, PhD, Menzies Institute for Medical Research, University of Tasmania; F. Pan, MD, Menzies Institute for Medical Research, University of Tasmania, and Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University; B. Antony, PhD, Student, Menzies Institute for Medical Research, University of Tasmania; F. Cicuttini, PhD, Department of Epidemiology and Preventive Medicine, Monash University; G. Jones, MD, Menzies Institute for Medical Research, University of Tasmania; C. Ding, MD, Menzies Institute for Medical Research, University of Tasmania, and Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, and Department of 
authors.forename: Changhai
authors.initials: C
authors.lastname: Ding
mesh_terms: D000367:Age Factors; D000368:Aged; D018771:Arthralgia / Q000473:pathology* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005122:Exudates and Transudates; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology* / Q000503:physiopathology; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011379:Prognosis; D016059:Range of Motion, Articular / Q000502:physiology*; D018570:Risk Assessment; D012720:Severity of Illness Index; D013585:Synovitis / Q000175:diagnosis* / Q000453:epidemiology; D013648:Tasmania; D016474:Weight-Bearing / Q000502:physiology*
keywords: EFFUSION; KNEE PAIN; OSTEOARTHRITIS; SYNOVITIS