Summary of included studies investigating the prevalence of MRI assessed knee OA features prevalence in asymptomatic uninjured populations
| Study | Cohort* | Subjects (knees), no. | Women, no. (%) | Age, years† | BMI, kg/m2† | MRI (T) | Risk of bias score |
| Alharis and Hameed,19 2012 | 80 (80) | 38 (48) | 40–60 | NR | 0.2 | 7 | |
| Antony et al,59 2016 | Childhood Determinants of Adult Health Study | 119 (119)‡ | 56 (47)§ | 35±3 (31–41)¶ | 25.7±4.3¶ | 1.5 | 11 |
| Baranyay et al,20 2007 | Melbourne Collaborative Cohort Study | 297 (297) | 186 (63) | 58±6 (40–69) | 25.2±3.8 | 1.5 | 13 |
| Beattie et al,92005 | 44 (44) | 33 (75) | 41±14 (20-68) | 25.4±4.4 | 1.0 | 7 | |
| Berry et al,29 2010 | 153 (153) | 124 (81) | 47±9 (25–60) | 32±9 | 1.5 | 6 | |
| Boden et al,30 1992 | 74 (74) | 41 (55) | 34 (16–65) | NR | 1.5 | 8 | |
| Brennan et al,63 2010 | Geelong Osteoporosis Study | 142 (142) | 142 (100) | 42±5 (30–49) | 27.3±6.3 | 1.5 | 11 |
| Brunner et al,31 1989 | Basketballers/Footballers | 5 (10)‡ | NR | NR (collegiate) | NR | 0.5/1.5 | 6 |
| Calixto et al,32 2016 | 85 (85) | 50 (59) | 50±9 | 24.0±3.4 | 3.0 | 8 | |
| Culvenor et al,44 2015 | 20 (20) | 7 (35) | 30±7 (21–44) | 22.8±1.8 | 3.0 | 7 | |
| Davies-Tuck et al,45 2008 | 20 (20) | 20 (100) | 61±6 | 25.3±4.2 | 1.5 | 7 | |
| Ding et al,46 2005 | 99 (99)‡ | 62 (63) | 45±7 (26–61) | 25.8±3.8 | 1.5 | 8 | |
| Dong et al,47 2017 | 20 (20) | 6 (30) | 35±11 | 23.5±3.0 | 1.5 | 5 | |
| Dore et al,64 2013 | Tasmanian Older Adult Cohort Study | 97 (97)‡ | 39 (40) | 65±7 (55–81) | 27.3±4.0 | 1.5 | 10 |
| Emad et al,48 2012 | 20 (40) | 12 (60) | 41±7 | 31.7±6.3 | 1.5 | 3 | |
| Fleming et al,78 2013 | 24 (24) | 5 (21) | 25±7 | 25.5±4.8 | 3.0 | 3 | |
| Foppen et al,65 2013 | 29 (55)‡ | 0 (0) | 24 (23–25)¶ | NR | 3.0 | 8 | |
| Fukuta et al,57 2002 | 115 (115) | 60 (52) | 48 (13–78) | NR | 0.5 | 7 | |
| Fukuta et al,49 2009 | 43 (43) | 34 (79) | 62 (40–79) | NR | 0.5 | 7 | |
| Guermazi et al,58 2012 | Framingham Osteoarthritis Study | 434 (434)‡ | 220 (51) | 63±8 (51–89) | 27.3±4.8 | 1.5 | 12 |
| Guymer et al,11 2007 | Victorian electoral role | 176 (176) | 176 (100) | 52±7 (40–67) | 27.1±5.5 | 1.5 | 12 |
| Hagemann et al,66 2008 | Runners | 10 (10) | 3 (30) | 37 (32–44) | NR | 1.5 | 8 |
| Jerosch et al,60 1996 | 66 (126)** | 32 (48) | 16–62** | NR | 1.0 | 8 | |
| Kaplan et al,61 2005 | Basketballers | 20 (40) | 0 (0) | 26 (21–36) | NR | 1.5 | 8 |
| Kaukinen et al,62 2016 | Oulu Knee Osteoarthritis Study | 63 (63) | 38 (60) | 55±14 | 24.8±3.2 | 3.0 | 8 |
| Kornaat and Van de Velde,672014 | Runners | 16 (32) | 3 (19) | 23±3 | 20.4±1.1 | 1.5 | 9 |
| Kornick et al,50 1990 | 54 (59)†† | 31 (48) | (20-74)†† | NR | 1.5 | 9 | |
| Krampla et al,68 2001 | Runners | 6 (6)‡ | 0 (0) | 37±8 (27–46) | NR | 1.0 | 9 |
| Kumar et al,51 2013 | 27 (42) | 9 (33) | 28±4 (20–35) | 22.7±2.1 | 3.0 | 6 | |
| Kursunoglu-Brahme et al,69 1990 | Runners | 10 (10) | 5 (50) | (20-35) | NR | 1.5 | 5 |
| Landsmeer et al,70 2016 | Prevention of Knee Osteoarthritis in Overweight Females Study | 300 (473)‡ | 300 (100) | 56±3 (50–60) | 32.2±4.3 | 1.5 | 9 |
| LaPrade et al,52 1994 | 54 (54) | 29 (54) | 29±5 (19–39) | NR | 1.0 | 5 | |
| Li et al,53 2009 | 200 (200) | 72 (36) | 31 (20–40) | NR | 1.5 | 8 | |
| Ludman et al,54 1999 | General gymnasts | 14 (26) 14 (24) | 5 (36) 4 (29) | 20 (18–23) 20 (18–22) | NR | 1.5 | 8 |
| Major & Helms,55 2002 | Basketballers | 17 (33)‡ | 5 (29) | NR (collegiate) | NR | 1.5 | 7 |
| Marik et al,56 2016 | 9 (9) | 3 (33) | 40±18 (23-69) | 22.1±2.6 | 7 | 4 | |
| Morgenroth et al,33 2014 | 14 (14) | NR | 55±2 (35–65) | 84.6±3.2‡ ‡ | 1.5 | 5 | |
| Negendank et al,34 1990 | General contralateral meniscal tear | 18 (36) 20 (20) | 18 (56) 4 (20) | 43±16 41±12 | 67.4±14.5 79.3±14.5 | 1.0 | 9 |
| Nozaki et al,35 2004 | 57 (86) | 37 (65) | 43 (18–79) | NR | 0.3 | 4 | |
| Pan et al,71 2011 | Osteoarthritis Initiative Healthy Control Cohort | 95 (95) | 58 (61) | 55±8 (45–78) | 24.2±2.9 | 3.0 | 11 |
| Pappas et al,10 2016 | Basketballers | 24 (24) | 12 (50) | (18-22) | NR | 3.0 | 9 |
| Peers et al,41 2014 | Basketballers Swimmers | 10 (10) 10 (10) | 10 (100) 10 (100) | 20 (19–22) 20 (19–23) | NR | 3.0 | 8 |
| Reinig et al,72 1991 | Footballers | 17 (17) | 0 (0) | (19-21) | NR | NR | 6 |
| Rennie and Finlay,42 2006 | 23 (36) | 5 (22) | 26 (15–41) | NR | 1.5 | 5 | |
| Schiphof et al,73 2014 | Rotterdam Study | 424 (836)‡ | 424 (100) | 55±4 | 26.3±4.3 | 1.5 | 10 |
| Schweitzer et al,43 1995 | 25 (50) | 7 (28) | 25 (20–46) | NR | 1.5 | 5 | |
| Shellock et al,36 1991 | Runners | 23 (23) | 15 (65) | 40 (25–55) | NR | 1.5 | 9 |
| Shellock and Mink,74 1991 | Runners | 4 (4)‡ | 2 (50)¶ | 37±4 (33–43)¶ | NR | 1.5 | 5 |
| Shellock et al,37 2003 | Triathletes | 13 (13) | 5 (38) | 48 (37–66) | NR | 1.5 | 9 |
| Souza et al,38 2013 | 19 (19) | 8 (42) | 39±10 | 23.5±3.4 | 3.0 | 6 | |
| Sowers et al,39 2011 | Michigan Study of Women’s Health Across the Nation Study | 159 (259)‡ | 159 (100) | 57±3 | 29.9±6.3 | 1.5/3.0 | 11 |
| Sritanyaratana et al,40 2014 | 20 (20) | 5 (25) | 32 (23–45) | NR | 3.0 | 3 | |
| Stahl et al,75 2008 | General runners | 12 (12) 10 (10) | 4 (33) 6 (60) | 37±11 31±5 | 75.8±12.6‡‡ 68.6±10.0‡‡ | 3.0 | 9 |
| Su et al,76 2013 | 16 (16) | 8 (50) | 33 (23–57) | 24.4 (20–29) | 3.0 | 6 | |
| Tarhan and Unlu ,24 2003 | 16 (29) | 12 (75) | 28±5 (46–77) | 28.2±3.7 | 0.23 | 6 | |
| van der Heijden et al,25 2006 | 70 (70) | 41 (59) | 23±6 (14–40) | 22.3±3.0 | 3.0 | 9 | |
| Walczak et al,26 2008 | Basketballers | 14 (25)‡ | 0 (0) | 26 (20–36) | NR | 0.3/0.7/1.5 | 6 |
| Wang et al,23 2012 | 38 (38) | 18 (47) | 42±7 (30–55) | 25.2±4.1 | 1.5 | 7 | |
| Wang et al,21 2015 | 16 (16) | 4 (25) | 34±10 (18-63) | 24.5±2.3 | 3.0 | 7 | |
| Wang et al,22 2017 | 30 (30) | 11 (37) | 28±5 (18–40) | 23.4±3.3 | 1.5/3.0 | 6 | |
| Wei et al,77 2017 | Footballers | 13 (25) | 0 (0) | 20±1 (18–22) | 34.2±3.2 | 3.0 | 6 |
| Whittaker et al,27 2017 | Alberta Youth Prevention of Early Osteoarthritis Study | 73 (146) | 45 (62) | 23±3 (15–27) | 23.6±2.6 | 1.5 | 9 |
| Zanetti et al,28 2003 | Contralateral meniscal tear | 100 (100) | 41 (41) | 43 (18–73) | NR | 1.0/1.5 | 8 |
*Participants are healthy volunteers from the general population unless otherwise indicated.
†Mean ± SD (range).
‡Subset of whole cohort without previous knee injury or surgery.
§Estimated from total sample reported in original publication.
¶Values represent total sample reported in original publication.
**After excluding participant group aged <16 years.
††Number of people/knees estimated after excluding participants aged 10–20 years.
‡‡Body mass, as BMI not reported.
BMI, body mass index; NR, not reported.