Background To analyse 5-year cost-effectiveness of early versus optional delayed acute anterior cruciate ligament (ACL) reconstruction.

Methods 121 young, active adults with acute ACL injury to a previously uninjured knee were randomised to early ACL reconstruction (n=62, within 10 weeks of injury) or optional delayed ACL reconstruction (n=59; 30 with ACL reconstruction within 6–55 months); all patients received similar structured rehabilitation. Real life data on health care utilisation and sick leave were obtained from regional and national registers. Costs and quality-adjusted life years (QALYs) were discounted at 3%. Full-analysis set (based on study randomisation) and as-treated analysis (according to actual treatment over 5 years) principles were applied.

Results Mean cost of early ACL reconstruction was €4695 higher than optional delayed ACL reconstruction (p=0.19) and provided an additional 0.13 QALYs (p=0.11). Full-analysis set showed incremental net benefit of early versus optional delayed ACL reconstruction was not statistically significantly different from zero at any level. As-treated analysis showed that costs for rehabilitation alone were €13 650 less than early ACL reconstruction (p<0.001). Results were robust to sensitivity analyses.

Conclusions In young active adults with acute ACL injury, a strategy of early ACL reconstruction did not provide extra economic value over a strategy of optional delayed ACL reconstruction over a 5-year period. Results from this and previous reports of the KANON-trial imply that early identification of individuals who would benefit from either early ACL reconstruction or rehabilitation alone might reduce resource consumption and decrease risk of unnecessary overtreatment.

Trial registration ISRCTN84752559.