Table 3

Constitutional/biomechanical factors and prevalence of knee osteoarthritis (n=597)

FactorsPrevalence (%)OR (95% CI)
CrudeAdjusted 1Adjusted 2
Age (years)
 40–5918/256 (7.0)111
 ≥6067/341 (19.6)3.23 (1.87 to 5.60)***3.08 (1.74 to 5.44)***3.49 (1.71 to 7.11)**
BMI (kg/m2)
 Normal (<25)46/359 (12.8)111
 Overweight (25 to <30)22/180 (12.2)0.95 (0.55 to 1.63)0.96 (0.55 to 1.69)0.90 (0.44 to 1.82)
 Obese (≥30)15/53 (28.3)2.69 (1.37 to 5.27)**2.49 (1.25 to 4.95)*2.35 (1.03 to 5.38)*
Sex
 Male54/356 (15.2)111
 Female31/241 (12.9)0.83 (0.51 to 1.33)1.08 (0.64 to 1.81)1.26 (0.65 to 2.44)
Knee injury
 No53/483 (11.0)111
 Yes26/88 (29.5)3.40 (1.98 to 5.84)***4.40 (2.45 to 7.88)***4.92 (2.58 to 9.38)***
Knee alignment, 20s
 Normal64/525 (12.2)111
 Varus13/43 (30.2)3.12 (1.55 to 6.29)**3.45 (1.61 to 7.36)**2.97 (1.11 to 7.94)*
 Valgus2/12 (16.7)1.44 (0.31 to 6.72)2.05 (0.40 to 10.45)2.08 (0.39 to 11.17)
Sport: weight-bearing
 No30/232 (12.9)11
 Yes55/365 (15.1)1.20 (0.74 to 1.93)1.04 (0.63 to 1.72)
Hypermobility, 20s
 ≤3/9 Beighton52/435 (12.0)111
 ≥4/9 Beighton15/69 (21.7)2.05 (1.08 to 3.89)*2.73 (1.36 to 5.48)**2.64 (1.21 to 5.78)*
Comorbidities
 No18/207 (8.7)111
 124/215 (11.2)1.32 (0.69 to 2.51)1.25 (0.64 to 2.43)1.09 (0.51 to 2.35)
 2 or more43/175 (24.6)3.42 (1.89 to 6.19)***2.53 (1.34 to 4.78)**2.61 (1.23 to 5.52)*
Index:ring finger ratio
 Index=ring21/157 (13.4)11
 Index>ring7/57 (12.3)0.91 (0.36 to 2.26)1.22 (0.47 to 3.16)
 Index<ring51/362 (14.1)1.06 (0.62 to 1.84)0.92 (0.52 to 1.64)
Finger nodes
 No73/549 (13.3)11
 Yes9/39 (23.1)1.96 (0.89 to 4.29)1.79 (0.78 to 4.11)
Sport: impact
 No64/487 (13.1)11
 Yes21/110 (19.1)1.56 (0.91 to 2.69)1.56 (0.87 to 2.77)
Widespread pain
 No79/549 (14.4)11
 Yes5/18 (27.8)2.29 (0.79 to 6.60)2.04 (0.67 to 6.21)
  • Adjusted 1: OR was adjusted for a priori confounders of age, sex and BMI.

  • Adjusted 2: a mutually adjusted model was fitted of the a priori confounders plus any significant factors/variables.

  • *P<0.05, **p<0.01, ***p<0.001.

  • BMI, body mass index.