| No OA | Premorbid OA | |
| n = 720 | n = 55 | |
| Male (%) | 44.2 | 47.3 |
| Mean age in years (SD) | 62.1 (8.3) | 66.7 (8.4) |
| Body mass index, mean (SD) | 27.7 (5.1) | 29.4 (6.2) |
| Knee pain on most days (in one or more knees) (%) | 21.4 | 57.4 |
| History of knee injury* in the MRI knee (%) | 8.1 | 7.4 |
| History of knee injury* in contralateral knee (%) | 9.3 | 38.9 |
MRI, magnetic resonance imaging; OA, osteoarthritis.
*Knee injury history was determined by a positive response to the question: Have you ever had an injury to your knee that required the use of a cane or crutches?