The Anterior Cruciate Ligament Injury Severity Scale (ACLISS) as a Predictor of Short-Term Reoperation and Functional Outcomes After ACL Reconstruction

The Anterior Cruciate Ligament Injury Severity Scale (ACLISS) was developed to classify the magnitude of damage to knee structures beyond the anterior cruciate ligament (ACL) (meniscus, cartilage, collateral ligaments, etc) at the time of ACL rupture. However, its validity in predicting clinical outcomes after ACL reconstruction (ACLR) has never been assessed. To determine whether ACLISS correlates with reoperation and patient-reported functional outcomes after ACLR. Cohort study; Level of evidence, 3. The records of all patients who underwent primary ACLR at a single institution between 2019 and 2022 with minimum follow-up of 2 years were reviewed. Patients were excluded if they had concomitant collateral ligament or posterior cruciate ligament repair/reconstruction or prior ipsilateral ACLR. ACLISS scores (0-12) and grades (grade 1: scores 0-3; grade 2: scores 4-7; grade 3: scores 8-12) were determined using preoperative magnetic resonance imaging and intraoperative arthroscopic findings based on the original published technique. The primary outcome was reoperation after ACLR. Secondary outcomes included International Knee Documentation Committee (IKDC) subjective scores and Marx activity scores. Bivariable and multivariable logistic regression analyses were performed to identify predictors of reoperation. Cox proportional hazards modeling and Kaplan-Meier survival analysis were used to evaluate time to reoperation. Statistical significance was defined as avalue <.05. A total of 324 patients met the inclusion criteria. The mean age was 29.3 &#xb1; 13.6 years, and 50.9% of the patients were male. The mean follow-up was 5.1 &#xb1; 0.8 years. Of the patients, 177 (54.6%) were classified as ACLISS grade 1 damage, with a mean score of 2.3 &#xb1; 0.9; 141 (43.5%) as grade 2, with mean score of 4.8 &#xb1; 0.9, and 6 (1.9%) as grade 3, with mean score of 8.2 &#xb1; 0.4. Overall, 87 (26.9%) patients required medial meniscus repair, and 82 (25.3%) patients required lateral meniscus repair. The overall ACL revision rate was 4.0%. A total of 34 (10.5%) patients had reoperation for any reason. The mean IKDC score was 84.4 &#xb1; 14.2, and the mean Marx score was 8.6 &#xb1; 5.4. There was no significant association between ACLISS grade and reoperation rate (grade 1: 10.2%; grades 2 and 3: 10.9%;= .832). In multivariable analysis, hybrid autograft with allograft augmentation was significantly associated with increased reoperation risk (OR, 7.68; 95% CI, 1.82-32.4;= .006). Survival analysis revealed that patients with grades 2 and 3 experienced earlier reoperations, with 69% occurring between 5 and 15 months compared to 22% for grade 1 (= .0086). IKDC and Marx scores did not differ significantly by ACLISS score. While ACLISS grade does not predict overall reoperation rates or functional outcomes when concomitant injuries are appropriately managed, patients with higher grades experienced earlier reoperation.