Are the osseous and tendinous-cartilaginous tibial tuberosity-trochlear groove distances the same on CT and MRI?

• Published in: Skeletal radiology Vol. 44; no. 8; pp. 1085 - 1093
• Main Authors: Hinckel, Betina Bremer, Gobbi, Riccardo Gomes, Filho, Eduardo Noda Kihara, Pécora, José Ricardo, Camanho, Gilberto Luis, Rodrigues, Marcelo Bordalo, Demange, Marco Kawamura
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-08-2015; Springer; Springer Nature B.V
• Subjects: Adolescent; Adult; Cartilage - anatomy & histology; Cartilage - diagnostic imaging; CT imaging; Female; Humans; Imaging; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Medicine; Medicine & Public Health; Middle Aged; Models, Anatomic; Nuclear Medicine; Observer Variation; Orthopedics; Patellofemoral Joint - anatomy & histology; Patellofemoral Joint - diagnostic imaging; Pathology; Radiology; Reproducibility of Results; Scientific Article; Sensitivity and Specificity; Tendons - anatomy & histology; Tendons - diagnostic imaging; Tibia - anatomy & histology; Tibia - diagnostic imaging; Tomography, X-Ray Computed - methods; Young Adult; Patellofemoral joint; Computed tomography; TTTG; Risk factor; MRI scan; Multislice; Patellar; Dislocation
• ISSN: 0364-2348; 1432-2161
• DOI: 10.1007/s00256-015-2118-4

Objective
To verify whether the tibial tuberosity-trochlear groove distance (TT-TG) and the tendinous-cartilaginous TT-TG (the distance between the patellar tendon and trochlear groove: PT-TG) are identical using computed tomography (CT) and magnetic resonance imaging (MRI) techniques.
Subjects and methods
The TT-TG and PT-TG distances were measured on the same knee samples by three observers (two measurements per observer) using CT and MRI scans collected retrospectively. The reproducibility of the measurements was assessed using the interclass correlation coefficient (ICC). The means and standard deviations of four measurements were calculated for each patient. A paired t-test was used to assess differences between measurements.
Results
Fifty knee samples (32 with patellar instability and 18 with other conditions) were evaluated. The inter- and intraobserver reliability was excellent for all four measurements (>0.8). On average, the TT-TG distance on MRI was 3.1–3.6 mm smaller than that on CT, and the PT-TG distance on MRI was 1.0–3.4 mm larger than the TT-TG distance on MRI.
Conclusion
The osseous TT-TG and tendinous-cartilaginous PT-TG distances determined by CT and MRI were not identical.