个性化股四头肌腱移植物在前交叉韧带重建中的应用：一种利用术前MRI预测移植物尺寸的新型连续方法
简介
回顾130例初次ACL重建采用全层股四头肌腱自体移植物患者，术前MRI矢状位测量肌腱厚度。ROC分析显示QT厚度<8.3 mm预测最终移植物直径<10 mm的敏感性98.2%、特异性39.1%，AUC为0.818；公式2√(WT/π)连续预测时90%移植物直径误差在±1.0 mm内。据此可依据术前MRI个体化确定股四头肌腱采集宽度，减少过度或不足采集。
英文摘要
BACKGROUND: The quadriceps tendon (QT) graft is increasingly popular in primary anterior cruciate ligament reconstruction (ACLR). However, postoperative quadriceps strength can be significantly weakened after use of a QT graft, compared to using hamstring tendon or bone-patellar tendon-bone grafts. There currently exists no continuous method to predict QT graft size based on preoperative magnetic resonance imaging (MRI) measurements; only dichotomous methods exist at limited cutoff values. PURPOSE: To (1) assess the accuracy of preoperative MRI QT thickness in predicting graft size dichotomously (<10 mm vs ≥10 mm), (2) assess the accuracy of the formula 2 ×√(WT/π) in predicting graft size continuously (within ±1.0 mm of the actual graft diameter), and (3) determine the interrater reliability of both methods; a minimum threshold of 10-mm QT graft diameter was selected given the young, high-demand athletic population in this cohort. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This is a retrospective review of 130 patients who underwent primary ACLR with full-thickness QT autografts at a single tertiary institution from January 1, 2022, to July 17, 2025. A novel, reproducible method to measure QT thickness on the MRI sagittal view at the most proximal patellar attachment site was developed. Two blinded reviewers independently measured QT thickness. Receiver operating characteristic (ROC) analysis was performed to determine the optimal threshold for predicting a final graft diameter <10 mm, with area under the curve (AUC) as the primary measure of discriminative ability. Sensitivity and specificity at the optimal threshold were additionally reported given their direct clinical relevance to intraoperative decision-making at a fixed cutoff. RESULTS: The mean age was 16.4 years (95% CI, 15.9-16.9 years), with 59 females and 71 males. ROC analysis identified a preoperative QT thickness <8.3 mm as the optimal threshold for predicting a final graft diameter <10 mm, with an AUC of 0.818, a sensitivity of 98.2%, and a specificity of 39.1%. The authors applied the formula 2 ×√(WT/π), demonstrating how graft diameter can be predicted from preoperative MRI, where T is the measured preoperative MRI graft thickness and W is the harvested graft width. Using this formula, the authors found that 90.0% of grafts were within ±1.0 mm of the actual graft diameter. CONCLUSION: The authors present a novel, numerically continuous way of predicting harvested quadriceps graft size. A preoperative QT thickness <8.3 mm is 98.2% sensitive and 39.1% specific in predicting a final graft diameter <10 mm. Personalizing the width of the harvested QT according to patient's tendon thickness and surgeon's desired graft size may be considered to minimize unnecessary over- or underharvesting of QT in the future.