Background and purpose — Patients in Sweden are insured against avoidable patient injuries. Prosthetic joint infections (PJIs) resulting from intraoperative contamination are regarded as compensable by the Swedish public insurance system. According to the Patient Injury Act, healthcare personnel must inform patients about any injury resulting from treatment and the possibility of filing a claim. To analyze any under-reporting of claims and their outcome, we investigated patients’ claims of PJI in a nationwide settingPatients and methods — The national cohort of PJI after primary total hip replacement, initially operated between 2005 and 2008, was established through cross-matching of registers and review of individual medical records. We analyzed 441 PJIs and the number of filed patients’ claims, with regards to incidence, outcome, and any national, sex-linked or socioeconomic differences.Results — We identified 329/441 (75%) patients with PJIs as non-claimants. 96% of the filed claims were accepted. 64 (57%) of claimants sustained permanent disability. 2 factors were found to statistically significantly reduce the odds of filing claims: patient’s age above 73 years and fracture as indication for surgery. There were no significant national, sex-linked, or socioeconomic differences.Interpretation — The incidence of patients’ claims of PJI is low but claims are usually accepted when filed. Healthcare personnel should increase their knowledge of the Patient Injury Act to inform patients about possibilities of eligible compensation.