Risk of radiographic tibio- and patellofemoral knee osteoarthritis (OA) and magnetic resonance imaging-detected meniscal tears and bursitis
| Disorder | Floor layers, n (%) | Graphic designers, n (%) | Adjusted, OR* (95% CI) |
| Tibiofemoral OA† | 17 (18.9) | 8 (16.7) | 2.46 (0.83 to 7.28) |
| Patellofemoral OA | 7 (7.8) | 9 (18.8) | 0.44 (0.14 to 1.37) |
| Tears of medial meniscus‡ | 62 (67.4) | 26 (53.1) | 2.82 (1.25 to 6.36) |
| Tears of lateral meniscus‡ | 12 (13.0) | 11 (22.4) | 0.78 (0.29 to 2.10) |
| Peripatellar bursitis | |||
| Prepatellar | 1 (1.1) | 5 (10.2) | 0.14 (0.02 to 1.55) |
| Superficial infrapatellar | 4 (4.3) | 2 (4.1) | 0.90 (0.14 to 5.75) |
| Deep infrapatellar | 10 (10.9) | 2 (4.1) | 3.53 (0.64 to 19.6) |
| Periarticular bursitis | 71 (77.2) | 31 (63.3) | 2.04 (0.89 to 4.69) |
| Subgastrocnemius | 57 (62.0) | 24 (49.0) | 1.76 (0.82 to 3.75) |
| Semimembranosus–gastrocnemius | 43 (46.7) | 17 (34.7) | 1.49 (0.67 to 3.29) |
| Others§ | 14 (15.2) | 0 (0) | – |
Values are represented as OR with 95% CI. Floor layers (n=92) are compared with graphic designers (n=49).
↵* OR is calculated relative to the reference group of graphic designers and adjusted for body mass index, previous knee traumas, knee straining sports activities and age.
↵† Missing radiographs in two floor layers and one graphic designer.
↵‡ Unilateral or bilateral meniscal tears.
↵§ Others: anserine, lateral (LCL) and medial (MCL) collateral ligament, iliotibial bursae and extracapsular synovial cysts.