Park Sin Hyung, Choi Wonchul, Yoon Siyeong, Rhie Jeongbae, Ahn Wooyeol, Oh Jongbeom, Han Dong Hun, Lee Soonchul
Department of Orthopaedic Surgery, Bucheon Hospital, Soonchunhyang University School of Medicine, Bucheon-si, Gyeonggi-do, Republic of Korea.
Department of Orthopaedic Surgery, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam-si, Gyeonggi-do, Republic of Korea.
Orthop J Sports Med. 2023 Jun 22;11(6):23259671221145228. doi: 10.1177/23259671221145228. eCollection 2023 Jun.
The tibial tuberosity-trochlear groove (TT-TG) distance measured on magnetic resonance imaging (MRI) is commonly used to decide the treatment for patellar instability; however, the patient's joint size is not considered in this measurement. The TT-TG index has been proposed as a knee size-adjusted measurement for tibial tuberosity location.
To evaluate the reliability of the TT-TG index compared with the TT-TG distance by analyzing variations in measurement according to age and sex in a pediatric Asian population.
Cohort study (diagnosis); Level of evidence, 3.
A total of 698 knee MRI scans were collected in patients between 4 and 18 years of age who did not have any patellofemoral problems. Patient age, sex, height, and weight were recorded. The scans were divided into 5 groups according to patient age (4-6 years, 46 scans; 7-9 years, 56 scans; 10-12 years, 122 scans; 13-15 years, 185 scans; and 16-18 years, 289 scans); MRI scans were also divided by sex (497 male, 201 female). Three independent observers measured the TT-TG distance and TT-TG index on each scan, and age- and sex-based differences in the measurements were evaluated after adjusting for body mass index (BMI). The reliability of the measurements was calculated with the intraclass correlation coefficient (ICC).
Good to excellent inter- and intraobserver agreement was found for TT-TG distance (ICC, 0.74) and TT-TG index (ICC, 0.88). The TT-TG distance was significantly different among the groups and increased with age, while variations in the TT-TG index were minimal between age groups and sexes. This finding was also consistent after compensating for the effect of BMI.
The TT-TG distance changed with age, while the TT-TG index was relatively constant. Therefore, the TT-TG index may be more reliable and effective for diagnosing and planning treatment, especially in children and adolescents.
磁共振成像（MRI）测量的胫骨结节-滑车沟（TT-TG）距离常用于决定髌股关节不稳的治疗方案；然而，该测量未考虑患者的关节大小。TT-TG指数已被提出作为一种根据膝关节大小调整的胫骨结节位置测量方法。
通过分析亚洲儿童人群中TT-TG指数随年龄和性别的测量差异，评估其与TT-TG距离相比的可靠性。
队列研究（诊断）；证据等级，3级。
收集了698例4至18岁无髌股关节问题患者的膝关节MRI扫描图像。记录患者的年龄、性别、身高和体重。扫描图像根据患者年龄分为5组（4至6岁，46例；7至9岁，56例；10至12岁，122例；13至15岁，185例；16至18岁，289例）；MRI扫描图像也按性别分组（男性497例，女性201例）。三位独立观察者在每张扫描图像上测量TT-TG距离和TT-TG指数，并在调整体重指数（BMI）后评估测量结果的年龄和性别差异。测量的可靠性通过组内相关系数（ICC）计算。
TT-TG距离（ICC，0.74）和TT-TG指数（ICC，0.88）的观察者间和观察者内一致性良好至优秀。TT-TG距离在各组间有显著差异且随年龄增加，而TT-TG指数在年龄组和性别之间的变化最小。校正BMI影响后，这一结果仍然一致。
TT-TG距离随年龄变化，而TT-TG指数相对恒定。因此，TT-TG指数在诊断和治疗方案制定中可能更可靠、有效，尤其对于儿童和青少年。
