Background and purpose - Patients in the Swedish healthcare system are insured against avoidable adverse events via Landstingens omsesidiga Forsakringsbolag (LoF). We assessed the reasons for compensation claims reported to LoF following an ACL injury.

Patients and methods - We searched the LoF database for compensation claims related to ACL injuries reported in 2005-2014, and cross-matched claims with the Swedish National Knee Ligament Register. We then performed a review of the medical records.

Results - We identified 530 eligible claims in 2005-2014. 352 (66%) claims were accepted by LoF and 178 claims were rejected. Accepted claims corresponded to fewer than 1% of ACL surgeries performed in the same period. The most common reasons for an accepted claim were postoperative septic arthritis followed by suboptimal surgery and delay in diagnosis and treatment.

Interpretation - There are different reasons for accepting a compensation claim following an ACL injury, which represents different treatment errors that can be avoided.