Low-Energy Multiligament Knee Injuries Are Associated With Higher Postoperative Activity Scores Compared With High-Energy Multiligament Knee Injuries: A Systematic Review and Meta-analysis of the Literature.

BACKGROUND

Multiligament knee injuries (MLKIs) can result from high-energy injury mechanisms such as motor vehicle accidents or low-energy injury mechanisms such as activities of daily living or sports.

PURPOSE/HYPOTHESIS: The purpose was to conduct a systematic review on postoperative patient-reported outcomes after MLKIs and to conduct a meta-analysis of comparable outcome variables based upon high- versus low-energy injury mechanisms. It was hypothesized that MLKIs with low-energy injury mechanisms would demonstrate significantly improved subjective clinical outcome scores compared with high-energy injuries.

STUDY DESIGN

Meta-analysis and systematic review.

METHODS

A systematic review was performed with the inclusion criteria of postoperative MLKI outcomes based upon high-versus low-energy mechanisms of injury with a minimum 2-year follow-up. Outcome scores included were the Lysholm knee scoring scale, Tegner activity scale, and the International Knee Documentation Committee (IKDC) score. High-energy mechanisms included motor vehicle accidents or falls from a height >5 feet; low-energy mechanisms included sports-related injuries, activities of daily living, or falls from <5 feet. A meta-analysis was performed comparing the outcome scores of high- versus low-energy mechanisms of MLKIs.

RESULTS

Overall, 1214 studies were identified, 15 of which were included in the systematic review and meta-analysis. Thirteen studies included surgical reconstructions of all injured ligaments. A total of 641 patients with 275 high-energy and 366 low-energy injuries were grouped for comparison in the meta-analysis. No significant differences in Lysholm scale (78.6 vs 78.0) or IKDC scores (69.0 vs 68.4) were found between high- and low-energy groups at a minimum of 2 years (range, 2-10 years) postoperatively ( > .05). The low-energy injury group demonstrated significantly higher Tegner activity scale scores (5.0 vs 3.9; = .03). There was no significant difference in failure rates between groups (3.5% vs 2.0%; = .23).

CONCLUSION

We found in this systematic review and meta-analysis that patients with low-energy mechanisms of MLKI surgery had improved postoperative Tegner activity scores compared with those patients with high-energy mechanisms after MLKI surgery. However, there were no differences in Lysholm score, IKDC score, or failure rates between high- and low-energy MLKI patients at an average of 5.3 years postoperatively.