Hamstring rehabilitation after injury: effect and grading the quality of evidence
| Outcomes | Effect size | ||||
| Large | Medium | Small | Trivial | ||
| Time to return-to-play | |||||
| Meta-analyses | Hedges’ g (95% CI) | ||||
| Lengthening hamstring exercises versus conventional hamstring exercises*; n=131, male football and track and field athletes67 | 1.23 (0.85 to 1.60); I2=0.0% | Low quality of evidence | |||
| HR (95% CI) | |||||
| Platelet-rich plasma versus placebo or rehabilitation*; n=154, various athletes67 | 1.03 (0.87 to 1.22); I2=75.0% | Moderate quality of evidence | |||
| Individual studies | Hedges’ g (95% CI) | ||||
| Lengthening hamstring exercises versus a criteria-based algorithm; n=48, male football30 | 0.23 (−0.34 to 0.80) | Low quality of evidence | |||
| Hamstring stretching four times per day versus hamstring stretching one time per day; n=80, track and field athletes22 | 2.31 (1.75 to 2.88) | Very low quality of evidence | |||
| Agility and trunk stabilisation versus hamstring stretching and strengthening; n=24, various athletes24 | 0.75 (−0.08 to 1.58) | Very low quality of evidence | |||
| Running and eccentric hamstring strengthening versus agility and trunk stabilisation; n=29, various athletes23 | 0.39 (−0.42 to 1.20) | Very low quality of evidence | |||
| HR (95% CI) | |||||
| Pain-threshold (≤4 on the 0 to 10 NRS) versus pain-free (0 on the 0 to 10 NRS) rehabilitation; n=37, male/female69 | 0.75 (0.40 to 1.40) | Low quality of evidence | |||
| Reinjuries | |||||
| Meta-analyses | RR (95 % CI) | ||||
| Lengthening hamstring exercises versus conventional hamstring exercises*; n=131, male football and track and field athletes67 | 0.25 (0.03 to 2.20); I2=0.0% | Very low quality of evidence | |||
| Platelet-rich plasma versus placebo or rehabilitation at 6–12 month follow-up*; n=129, various athletes67 | 0.88 (0.45 to 1.71); I2=0.0% | Moderate quality of evidence | |||
| Individual studies | |||||
| Criteria-based algorithm versus lengthening hamstring exercises at 6 month follow-up, n=48, male football30 | 0.17 (0.02 to 1.28) | Low quality of evidence | |||
| Agility and trunk stabilisation versus hamstring stretching and strengthening at 12 months follow-up, n=24, various athletes24 | 0.10 (0.01 to 0.70) | Very low quality of evidence | |||
| HR (95 % CI) | |||||
| Pain-threshold (≤4 on the 0 to 10 NRS) versus pain-free (0 on the 0 to 10 NRS) rehabilitation at 6 month follow-up; n=37, male/female69 | 1.05 (0.14 to 7.47) | Low quality of evidence | |||
*Based on pooled data from meta-analysis. RR (Risk ratio); HR; I2 (Heterogeneity in study results); NRS (Numeric Rating Scale); the effect of treatment regarding return to play is assessed by Hedges’ g as trivial (g<0.2), small (g≥0.2), medium (g≥0.5) and large (g≥0.8).39 The effect of treatment on reinjuries is assessed as risk ratio as trivial (RR >0.78), small (0.78≥ RR >0.61), medium (0.61≥ RR >0.47) and large (RR ≤0.47).47