Table 3 Studies examining the effect of knee injury and/or alignment on the relationship between physical activity and risk for developing knee OA
Author (year) | Study design/participants | Measure(s) of OA | Measure(s) of physical activity | Results: effect of alignment/injury |
|---|---|---|---|---|
Studies investigating self-reported symptomatic OA | ||||
   Sutton et al. (2001) [20] | Retrospective case-control study/1,080 healthy participants | Self-reported, symptomatic | Self-reported; parameters not specified | Past history of knee injury was associated with increased risk for knee OA (OR 8.0, 95% CI 2.0 to 32.0) |
   Kujala et al. (1999) [19] | 11-year cohort study/269 runners and 188 control individuals | Self-reported, symptomatic | Self-reported; MET index (intensity, duration and frequency); level of breathlessness | Runners reported knee OA more often than control individuals (OR 1.79, 95% CI 1.10 to 3.54 [P = 0.025]) |
| Â | Â | Â | Â | The age-adjusted OR for having had knee ligament or meniscus injury was 1.62 (95% CI 0.99 to 2.65 [P = 0.055]) in runners compared with control individuals |
Studies investigating self-reported physician diagnosed OA | ||||
   Kujala et al. (1999) [19] | 11-year cohort study/269 runners and 188 control individuals | Self-reported, physician diagnosed | Self-reported; MET index (intensity, duration and frequency); level of breathlessness | Runners reported knee OA more often than control individuals (OR 1.79, 95% CI 1.10 to 3.54 [P = 0.025]). |
| Â | Â | Â | Â | The age-adjusted OR for having had knee ligament or meniscus injury was 1.62 (95% CI 0.99 to 2.65 [P = 0.055]) in runners compared with control individuals |
Radiographic studies investigating structural OA | ||||
   Kujala et al. (1995) [15] | Retrospective cohort study/117 male former top-level athletes | Radiographic, structural; clinical | Self-reported; parameters not-specified | The risk of knee OA was increased in those with previous knee injuries (OR 4.73, 95% CI 1.32 to 17.0) |
   McDermott and Freyne (1983) [16] | Cross-sectional study/20 middle/long-distance runners | Radiographic, structural; clinical examination and arthroscopy | Self-reported; years of training/competition, training mileage | OA was reported in 6 of the 20 runners; athletes with degenerative changes had been running for a greater number of years (P < 0.05) |
| Â | Â | Â | Â | Participants with degenerative changes had greater incidence of genu varum and had experienced more knee injuries (P < 0.05) |