Table 1.
Characteristics of study participants (N = 198)
| At time of MRI | |
|---|---|
| Age (years) | 67.1 (7.7) |
| Gender (n, % male) | 85 (43.4) |
| BMI (kg m−2) | 27.2 (4.6) |
| Heavy domestic chores in previous 7 days, n (%) | 163 (76.2) |
| Vigorous physical activity in previous 7 days, n (%) | 50 (23.4) |
| WOMAC pain score, median | 20 |
| Femoral head cartilage volume (mm3) | 3259 (810) |
| Femoral head bone area (mm2) | 1615 (266) |
| Femoral head cartilage defects, n (%) | |
| Anterior | 9 (4.5) |
| Central superolateral | 72 (36.7) |
| Central inferomedial | 104 (53.1) |
| Posterior | 36 (18.2) |
| Femoroacetabular BMLs, n (%) | |
| Anterior | 34 (17.2) |
| Central superolateral | 40 (20.4) |
| Central inferomedial | 12 (6.1) |
| Posterior | 22 (11.1) |
| Occupational heavy lifting n (%) | |
| Aged 18 to 30 years | 114 (59.7) |
| Previous 10 years | 76 (38.8) |
| Persistence score | |
| No time point | 46 (28.7) |
| One time point | 52 (32.5) |
| Both time points | 62 (38.8) |
| Occupational stair climbing n (%) | |
| Aged 18 to 30 years | 37 (18.9) |
| Previous 10 years | 23 (11.7) |
| Persistence score | |
| No time point | 122 (62.2) |
| One time point | 28 (14.3) |
| Both time points | 13 (6.6) |
Mean (standard deviation) unless otherwise stated. MRI, magnetic resonance imaging; BMI, body mass index; WOMAC, Western Ontario and McMasters Universities Arthritis Index; BMLs, bone marrow lesions.