Table 1.
Subject characteristics and baseline WORMS scores of high and low physical activity and types of physical activity.
| Subject Characteristics | High Impact (N=244) | Low Impact (N=171) | p-value | Ball sports (N=70) | Bicycling (N=74) | Elliptical trainer (N=41) | Jogging/running (N=94) | Racquet sports (N=80) | Swimming (N=56) | p-value |
|---|---|---|---|---|---|---|---|---|---|---|
| Age (years) | 59.2 (±8.9) | 59.4 (±8.9) | 0.885 | 57.8 (±8.9) | 57.6 (±8.9) | 56.0 (±9.0) | 58,5 (±8.8) | 61.4 (±8.9) | 64.1 (±8.9) | 0.501 |
| BMI (kg/m3) | 29.5 (±3.4) | 30.1 (±3.5) | 0.069 | 29.7 (±3.4) | 30.0 (±3.5) | 30.6 (±3.5) | 29.3 (±3.4) | 29.6 (±3.4) | 30.0 (±3.5) | 0.501 |
| Sex | F=84 (34) M=160 (66) |
F=99 (58) M=72 (42) |
≥0.001 | F=10 (14) M=60 (86) |
F=42 (57) M=32 (43) |
F=21 (51) M=20 (49) |
F=43 (48) M=49 (52) |
F=29 (36) M=51 (64) |
F=36 (64) M=20 (36) |
≤0.001 |
| K/L score | 0=82 (34) 1=51 (21) 2=75 (11) 3=36 (15) |
0=56 (33) 1=36 (21) 2=56 (33) 3=23 (13) |
0.965 | 0=20 (28.5) 1=20 (28.5) 2=19 (27) 3=11 (16) |
0=25 (34) 1=17 (23) 2=20 (27) 3=12 (16) |
0=13 (32) 1=5 (12) 2=18 (44) 3=5 (12) |
0=38 (40) 1=19 (20) 2=27 (29) 3=10 (11) |
0=24 (30) 1=12 (15) 2=29 (36) 3=15 (19) |
0=18 (32) 1=14 (25) 2=18 (32) 3=6 (11) |
0.507 |
| Ethnicity | Caucasian=198 (81) African/American=43 (18) Asian=3 (1) |
Caucasian=150 (88) African/American=19 (11) Asian=2 (1) |
0.185 | Caucasian=56 (80) African/American=14 (20) Asian=0 |
Caucasian=67 (90.5) African/American=7 (9.5) Asian=0 |
Caucasian=33 (80.5) African/American=8 (19.5) Asian=0 |
Caucasian=73 (78) African/American=20 (21) Asian=1 (1) |
Caucasian=69 (86.2) African/American=9 (11.2) Asian=2 (2.5) |
Ceucasian=50 (89) African/American=4 (7) Asian=2 (4) |
0.099 |
| Knee surgery/arthroscopy | Y=6 (2) N=231 (95) *=7 (3) |
Y=2 (1) N=166 (97) *=3 (2) |
0.339 | Y=2 (3) N=65 (93) *=3 (4) |
Y=0 N=73 (99) *=1 (1) |
Y=1 (1) N=40 (99) |
Y=1 (1) N=89 (95) *=4 (4) |
Y=3 (4) N=77 (96) |
Y=1 (2) N=53 (95) *=2 (3) |
0.620 |
| KOOS pain | 86 (±15.4) | 88 (±15.1) | 0.467 | 82.4 (±15.5) | 86.5 (±15.2) | 89.1 (±15.3) | 88.2 (±15.4) | 87.9 (±15.4) | 87.8 (±15.2) | 0.501 |
| KOOS symptoms | 88 (±13.5) | 89 (±13.2) | 0.319 | 86.1 (±13.5) | 87.5 (±13.2) | 91.2 (±13.3) | 88.2 (±13.6) | 88.2 (±13.5) | 89.1 (±13.2) | 0.501 |
| WORMS Baseline Scores | High Impact vs Low Impact | p-value | Ball Sports | p-value | Bicycling | p-value | Elliptical trainer | p-value | Jogging/running | p-value | Racquet sports | p-value | Swimming | p-value |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Overall Worms score | 1.83 [−0.56,4.22] | 0.13 | 1.25 [−1.51,4.02] | 0.37 | 0.05 [−2.51,2.63] | 0.96 | −1.91[−5.45,1.63] | 0.28 | −0.46 [−2.62,1.68] | 0.67 | 1.54[−1.10,4.19] | 0.25 | −1.14 [−3.82,1.52] | 0.40 |
| Cartilage | ||||||||||||||
| Cartilage Sum | 0.88 [−0.15,1.93] | 0.095 | 0.80 [−0.43,2.03] | 0.20 | −0.12 [−1.27,1.10] | 0.82 | −0.47[−2.05,1.09] | 0.55 | −0.50 [−1.46,0.45] | 0.30 | 1.47[0.30,2.64] | 0.014 | −0.37 [−1.56,0.81] | 0.53 |
| Meniscus | ||||||||||||||
| Meniscus Sum | 0.46[−0.50,1.43] | 034 | 0.45 [−0.68,1.58] | 0.43 | −0.10[1.15,0.94] | 0.84 | −0.84 [−2.29,0.60] | 0.25 | −0.07[−0.95,0.80] | 0.86 | −0.35[−1.43,0.72] | 0.52 | −0.38 [−1.47,0.70] | 0.49 |
The Table shows the subjects characteristics and WORMS scores at baseline. Continuous data are expressed as mean ± SD. Categorical data are presented in numbers with percentage in parenthesis. P values are for differences between participants with different types of physical activity and were calculated using either Pearson’s X2 test (categorical variables) or analysis of variance (parametric testing). Baseline WORMS scores are listed as average WORMS score adjusted for common risk factor of knee OA age, sex, race and baseline BMI, with [95% Confidence interval]. Significant statistical results (p=≤0.050) are in bold.