Hospital for Special Surgery ACL Registry: 2-Year Outcomes Suggest Low Revision and Return to OR Rates.

BACKGROUND: Anterior cruciate ligament (ACL) injuries are among the most common knee injuries. Patient outcomes, rate of subsequent operations, and rate of subsequent ACL reconstruction following primary ACL reconstruction need to be evaluated.

QUESTIONS/PURPOSES: This study was designed to answer the following questions: (1) What is the return to surgery (OR) rate following primary ACL reconstruction and (2) what is the revision ACL reconstruction rate?

METHODS: Data was drawn from the Hospital for Special Surgery (HSS) ACL Registry. International Knee Documentation Committee (IKDC) Subjective Knee Evaluation, Lysholm-Tegner Scales, Marx Activity Scale, and SF12 were completed by patients at baseline, 1-, and 2-year follow-up. Clinical data and intraoperative data were registered by surgeons on an intraoperative form. Subsequent surgery rates were determined by evaluating the medical records for subsequent surgery, laterality, surgeon, procedure description, and type of anesthesia.

RESULTS: The majority of the ACL reconstructions performed were autograft (76.6%) with the most common graft being bone-patellar tendon-bone (BTB) autograft (47.2%), hamstring autograft (21.9%), and Achilles allograft (18.2%). Average IKDC score improved from 51.9 (SD 16.1) at baseline to 83.5 (SD 14.2) at 2-year follow-up. Females had a 2.5-point lower IKDC and 1.4-point Marx scores compared to males. Of the enrolled patients, 7.3% had revision ACL surgery with 70.4% being ipsilateral ACL surgery. Of the enrolled patients, 10.3% had subsequent knee surgery with 72.3% being ipsilateral knee surgery. Multivariable logistic regression analysis showed that patients less than 18 years of age at the time of their index surgery were over three times more likely to undergo a revision ACL reconstruction compared to older patients and were at four times higher risk than older patients for any subsequent knee surgery.

CONCLUSION: Understanding ACL surgery, patient outcomes, and risk factors for revision ACL surgery and subsequent knee surgery after primary ACL reconstruction is essential. Patients less than 18 years of age have a higher risk of subsequent knee surgery and subsequent ACL surgery than older patients.