Anatomical features and tibial tunnel placement: influence on graft maturity at a 2-year follow-up after anterior cruciate ligament reconstruction

BackgroundAnterior cruciate ligament (ACL) reconstruction is a common surgical procedure; however, the anatomical features influencing graft maturation post-surgery remain partially understood.PurposeTo investigate whether knee-joint anatomical structure is associated with graft maturation 2 years after ACL reconstruction (ACLR).Material and MethodsData from 54 patients who underwent arthroscopic single bundle ACLR using hamstring tendons was analyzed after a 2-year follow-up in this retrospective study. The signal-to-noise quotient (SNQ) of the intra-articular graft was measured using magnetic resonance imaging. The median SNQ was used to divide patients into a high-signal group (group A) and a low-signal group (group B). Data on patient demographics, knee anatomy, and tunnel placement were collected.ResultsSignificant differences in the graft sagittal obliquity (45 vs. 52, <i>P </i>= 0.001), tibial tunnel placement (29.9 ± 2.15 vs. 34.71 ± 1.72, <i>P </i>= 0.028), lateral tibial posterior slope (LTPS) (12 vs. 8, <i>P </i>< 0.001) were observed between groups A and B after ACLR (<i>t</i>-test or Mann-Whitney U test, <i>P </i>< 0.05). Univariate analysis showed that graft sagittal obliquity (odds ratio, (OR) [95% (confidence interval, CI)]: 0.88 [0.78, 0.97]) and tibial tunnel placement (OR [95% CI]: 0.78 [0.60, 0.96]) were protective factors, whereas LTPS was a risk factor for ligamentization (OR [95% CI]: 1.63 [1.22, 2.38]). No significant difference was found in sex, injury-to-operation time, or location (<i>P </i>> 0.05).ConclusionAnatomic features and tibial tunnel placement may influence the ligamentization process of the ACL graft, aiding clinicians in the early prediction of healing outcomes after ACLR.