Background Various knee injuries accompanying anterior cruciate ligament (ACL) has been established as a significant risk factor for developing knee osteoarthritis (OA). However, research using big cohort sample to examine relationship between ACL and OA have not been conducted yet.

Objective The purpose of this study is to examine the impact of ACL injury and other related knee joint structures on the development of OA using National Health Insurance Service (NHIS) cohort data.

Design Epidemiological retrospective cohort study.

Setting Epidemiological study of active adult population from National Health Insurance Service cohort database.

Patients (or Participants) The subjects consist of a total of 514,866 randomly selected NHIS cohort group (age, 52.6 years; BMI, 24.0) between 2002 and 2013. Individual with an ACL injury regardless of accompany of other structural damage were prospectively followed-up until 2013.

Interventions (or Assessment of Risk Factors) ACL injury with multiple knee joint ligament damage (AL); ACL injury with meniscus damage (AM); single ACL injury (AS); and group without any knee joint ligaments or meniscus injury (Control).

Main Outcome Measurements Adjusted odds ratio (OR) and 95% confidential interval (CI) were estimated.

Results A total of 1,175 (2.28 per 1,000 population) ACL patients were found in 2002 and followed-up until 2013. AS (OR, 1.79; CI, 1.41–2.26), AL (OR, 2.77; CI, 2.37–3.25) and AM (OR, 2.78; CI, 2.37–3.26) demonstrated 1.79, 2.77, and 2.78 times greater to develop OA than control group respectively. AL (OR, 1.55; CI, 1.17–2.06) and AM (OR, 1.56; CI, 1.17–2.07) are approximately 1.6 times greater than AS.

Conclusions This study clearly provide evidence that multiple knee joint injury is as high as approximately 3 times greater risk of developing OA than control and even 1.6 times greater than AS. Therefore, clinician should consider appropriate treatment option for ACL injured patient to prevent progression to OA.