ArticleJournal of experimental orthopaedics2018
Effects of knee flexion and extension on the tibial tuberosity-trochlear groove (TT-TG) distance in adolescents.
Article in Journal of experimental orthopaedics, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 1 of them a synthesis that pooled it.
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Who cites it
16 citing papers in PubMed, 1 synthesis or guideline pooled it, 27 citations in OpenAlex.
- Performance of artificial intelligence in automated measurement of patellofemoral joint parameters: a systematic review.Journal of orthopaedic surgery and research · 2025Pooled it
- Patellofemoral instability: Anatomy, imaging techniques, and clinically relevant measurements.Skeletal radiology · 2026Review
- Overcoming Limitations in Tibial Tubercle-Trochlear Groove Distance Measurement: A Study of Its Reproducibility and Reliability in High-Grade Trochlear Dysplasia.Orthopaedic journal of sports medicine · 2026Article
- Influence of the screw-home mechanism on TT-TG distance: a 3D kinematic simulation study.European journal of orthopaedic surgery & traumatology : orthopedie traumatologie · 2026Article
- Anterior Knee Pain and Excessive External Tibial Torsion in Female Patients: Rationale and Outcomes of Rotational Tibial Osteotomy.Journal of clinical medicine · 2026Review
- Knee rotation significantly increases measured tibial tubercle-trochlear groove distance in female patients with anterior knee pain: Findings after rotational measurement correction.Journal of experimental orthopaedics · 2026Article
- Arthroscopic Management of Patellar Instability in Skeletally Immature Patients: Current Concepts and Future Directions.Journal of clinical medicine · 2025Review
- Tibial tuberosity-trochlea groove distance is dependent on flexion angle and intra-articular version in different magnetic resonance imaging recording techniques.Journal of experimental orthopaedics · 2025Article
- The diagnostic value of TT-TG and TT-ME distances in the assessment of patellofemoral instability.Japanese journal of radiology · 2024Article
- Tibial Tubercle Trochlear Groove Distance Does Not Correlate With Patellar Tendon Length in Patients Who Underwent Anterior Cruciate Ligament Reconstruction.Arthroscopy, sports medicine, and rehabilitation · 2024Article
- The tibial tubercle-trochlear groove distance: a comparison study between EOS and MRI in the paediatric population.Skeletal radiology · 2024Article
- Future Directions in Patellofemoral Imaging and 3D Modeling.Current reviews in musculoskeletal medicine · 2022Review
- Measurement of tibial tuberosity-trochlear groove distance by MRI: assessment and correction of knee positioning errors.Skeletal radiology · 2021Article
- Tibial tuberosity-tibial intercondylar midpoint distance measured on computed tomography scanner is not biased during knee rotation and could be clinically more relevant than current measurement systems.International orthopaedics · 2021Article
- Comparative study of the tibial tubercle-trochlear groove distance measured in two ways and tibial tubercle-posterior cruciate ligament distance in patients with patellofemoral instability.Journal of orthopaedic surgery and research · 2020Article
- Tibial Tubercle-Trochlear Groove Distance Is a Reliable and Accurate Indicator of Patellofemoral Instability.Clinical orthopaedics and related research · 2019Article
Corrections and comments
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Authors and funding
8 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundMeasurement of the tibial tubercle-trochlear groove (TT-TG) distance is used to assess patellofemoral instability and rotation. Since patellofemoral instability and acute patellar dislocation are common among adolescents, it is important to clarify the relationship between TT-TG distance and various flexion and extension angles in asymptomatic children. The purpose of the present study was to determine how knee flexion and extension influence TT-TG-distance values measured using 3D imaging in an anatomic axial plane among asymptomatic adolescents.
methodsWe performed magnetic resonance imaging (MRI) of 26 knees in 13 adolescents (8 boys and 5 girls) of 11-17 years of age, with no known patellofemoral disorders. Imaging was performed with 3.0 T MRI with the knee at four separate angles of flexion between 0° and 30°. Measurements were made by two independent blinded raters.
resultsThe mean TT-TG distance in millimetres was 11.1-0.29 × the angle in degrees. TT-TG distance decreased with greater flexion, showing a mean decrease of 0.29 mm (SD, 0.04) per degree of increased flexion (p < 0.001). We found significant inter-observer (Pearson's r = 0.636, p = 0.03) and intra-observer (Pearson's r = 0.792, p ≤ 0.001) correlations. TT-TG values were not significantly correlated with age, length, weight, or body mass index. The rate of TT-TG change (change between consecutive TT-TG values/change between consecutive angles) was significantly negatively correlated with length (p = 0.014), weight (p = 0.004), and body mass index (p = 0.025).
conclusionsOur data revealed that TT-TG distance assessed in the anatomic axial plane decreased with greater flexion in adolescent. Moreover, this effect of knee angle was stronger in smaller subjects. These findings support the need for a standardized protocol for TT-TG distance measurement in adolescents.
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