Influence of hamstring tendon and bone-patellar tendon-bone autografts on worsened patient reported outcome measurements in revision anterior cruciate ligament reconstruction: Comparing outcomes between primary and revision reconstructions

BACKGROUND: This study aimed to compare the clinical outcomes and patient reported outcome measurement scales (PROMs) between hamstring tendon (HT) or bone-patellar tendon-bone (BTB) grafts in each primary and revision anterior cruciate ligament (ACL) reconstruction. Additionally, the clinical outcomes and PROMs between primary and revision surgeries were compared. METHODS: A total of 150 patients (109 primary and 41 revision ACL reconstructions) were enrolled and followed up for an average of 3.9 years (2 years minimum). Knee injury and osteoarthritis outcome scores (KOOS) were examined as PROMs. Side-to-side differences of anterior knee laxity were assessed using KT-1000 and were recorded at the final follow-up. After categorizing patients into HT and BTB reconstruction groups, regression analysis was performed to determine the relationship between revision surgery and changes in KOOS. RESULTS: In patients who underwent primary surgery, there was no significant difference in side-to-side differences of anterior laxity and KOOS between HT and BTB grafts. In those who underwent revision surgery, BTB grafts had a higher KOOS for activities of daily living (ADL) than HT grafts (p = 0.032). Comparing primary and revision surgeries, postoperative side-to-side differences of anterior laxity in the revision group were significantly larger than those in the primary group (p = 0.001). The KOOS for sports after overall revision reconstruction was significantly lower than that after primary reconstruction (p = 0.026). Comparing the KOOS after dividing all patients into HT and BTB reconstruction groups, in the HT reconstruction group, postoperative KOOS results were not different in any subscale from BTB grafts. In contrast, the KOOS for sports (p = 0.008) and QOL (p = 0.039) were significantly lower in revision surgery than in primary surgery. Furthermore, regression analysis including multiple confounders in the HT reconstruction group showed revision surgery using HT graft was correlated with worsened KOOS for symptoms (p = 0.012) and sports (p = 0.010). Revision surgery using BTB graft was not correlated with decreased KOOS. CONCLUSIONS: There were no differences between the clinical outcome and KOOS in primary and revision surgery, except for ADL scores following revision ACL reconstruction using BTB graft. Side-to-side difference of anterior laxity and KOOS for sports following revision ACL reconstruction were inferior to those following primary ACL reconstruction. Furthermore, revision ACL reconstruction using HT grafts were correlated with low scores in KOOS for symptoms and sports, while there was no difference of anterior laxity between BTB and HT grafts in revision surgery.