Table 2.
Characteristics of study participants; floor layers (n = 134) and graphic designers (n = 120)
| Floor layers | Graphic designers | |||
| Age (years) mean, range | 52.6 | 39–68 | 57.9 | 40–70 |
| Trade seniority* (years) mean, range | 29.2 | 3–49 | 35.6 | 8–54 |
| BMI† (kg/m2) mean, range | 26.4 | 20–41 | 26.0 | 17–42 |
| Knee-straining sports‡ n, (%) | 71 | (53) | 80 | (67) |
| Knee osteoarthritis§ n, (%) | ||||
| Grade 1 | ||||
| - Tibiofemoral | 10 | (8) | 2 | (2) |
| - Patellofemoral | 5 | (4) | 8 | (7) |
| Grade 2–3 | ||||
| - Tibiofemoral | 7 | (5) | 7 | (6) |
| - Patellofemoral | 4 | (3) | 8 | (8) |
| Grade 4–6 | ||||
| - Tibiofemoral | 5 | (4) | 6 | (5) |
| - Patellofemoral | 3 | (2) | 5 | (4) |
* Years of employment in the trade
† Body mass index
‡ Defined as football, handball, badminton, tennis, volleyball, ice hockey, and weight lifting
§ Combined tibiofemoral and patellofemoral osteoarthritis; floor layers n = 3, graphic designers n = 6