Table 2.
Summary of Reviewed Studies
| Study Characteristic |
Study |
|||||
| Hewett et al,3 1999 |
Soderman et al,25 2000 |
Heidt et al,39 2000 |
Myklebust et al,26 2003 |
Steffen et al,32 2008 |
Kiani et al,33 2010 |
|
| Study design (CEBM level of evidence) | Prospective cluster cohort (2b) | Prospective randomized cluster cohort (2b)a | Prospective randomized (1b) | Prospective cross-over (2b) | Prospective randomized cluster cohort (1b) | Prospective cluster cohort (2b) |
| Sport | Volleyball, soccer, and basketball | Soccer | Soccer | Handball | Soccer | Soccer |
| Group size (athletes), n | C = 15 teams (463) | C = 6 teams (78) | C = 258 players | C = 60 teams (942) | C = 51 teams (947) | C = 49 teams (729) |
| I = 15 teams (366) | I = 7 teams (62) | I = 42 players | First I = 58 teams (855) | I = 58 teams (1073) | I = 48 teams (777) | |
| Second I = 52 teams (850) | ||||||
| Age, y | 14–18 | C mean = 20.5 ± 5.4 | 14–18 | Overall mean = 21–22 | Overall mean = 15.4 ± 0.8 | C mean = 15.0 (range, 13.0–17.6) |
| I mean = 20.4 ± 4.6 | I mean = 14.7 (range, 12.7–18.6) | |||||
| Intervention provider | Athletic trainers and physical therapists | Physical therapistsc | Athletic trainers | Physical therapists | Norwegian Football Association certified coaches and physical therapists | Physician, physical therapist, and coaches |
| Intervention Type | Stretching, plyometrics, and weight training | Balance with balance boards | Cardiovascular, plyometrics, strength, flexibility, agility, and sport-specific drills | Balance with mats and wobble boards | Core stability, balance, and plyometrics | Core strengthening, and balance |
| Length, min | 60–90 | 10–15 | 75 | 15 | 15 | 20–25 |
| Frequency | 3 d/wk | Each day for 30 d then 3 d/wk for rest of the season | 20 sessions (2 treadmill and 1 plyometric-based session per week) | 3 d/wk for 5–7 wk then 1 d/wk for rest of the season | 15 consecutive sessions then once a week for rest of the season | 2 d/wk for about 2 months then 1 d/wk for rest of the season |
| Duration | 6 wk | 6 mo | 7 wk | 5 mo | 7.5 mo | 9 mo |
| ACL injuries (mechanism), nb | C = 5 (5 noncontact) | C = 1 (no report) | C = 8 (no report) | First year (1998–1999) C = 29 (no report) | C = 5 (2 noncontact) | C = 5 (5 noncontact, 2 combined ACL and MM injury) |
| I = 2 (2 noncontact, 1 combined ACL and MCL injury) | I = 4 (no report, 1 combined ACL and MCL injury) | I = 1 (contact) | Second year (1999–2000) I = 23 (no report) | I = 4 (3 noncontact) | I = 0 | |
| Third year (2000–2001) I = 17 (no report) | ||||||
Abbreviations: ACL, anterior cruciate ligament; C, control; CEMB, Centre of Evidence Based Medicine; I, intervention; MCL, medial collateral ligament; MM, medial meniscus.
a
Although the study was a randomized controlled design, the follow-up rate was low (51.2%). Therefore, the level of evidence was rated as 2b.
b
No report indicates the researchers did not provide a description of the mechanism of ACL injury.
c
Physical therapists instructed the participants in the intervention, but the intervention was performed as a home program.