Systematic Technique-Dependent Differences in CT Versus MRI Measurement of the Tibial Tubercle–Trochlear Groove Distance

2015 ◽  
Vol 43 (3) ◽  
pp. 675-682 ◽  
Author(s):  
Charles P. Ho ◽  
Evan W. James ◽  
Rachel K. Surowiec ◽  
Coley C. Gatlin ◽  
Michael B. Ellman ◽  
...  
2021 ◽  
pp. 036354652098781
Author(s):  
Mathias Paiva ◽  
Lars Blønd ◽  
Per Hölmich ◽  
Kristoffer Weisskirchner Barfod

Background: Tibial tubercle–trochlear groove (TT-TG) distance is often used as a measure of lateralization of the TT and is important for surgical planning. Purpose: To investigate if increased TT-TG distance measured on axial magnetic resonance images is due to lateralization of the TT or medialization of the TG. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 84 knees (28 normal [NK], 28 with trochlear dysplasia [TD], and 28 with patellar dislocation without TD [PD]) were examined. The medial border of the posterior cruciate ligament (PCL) was chosen as the central anatomic landmark. The distance from the TT to PCL (TT-PCL) was measured to examine the lateralization of the TT. The distance from the TG to the PCL (TG-PCL) was measured to examine the medialization of the TG. Between-group differences were investigated by use of 1-way analysis of variance. Results: The mean values for TT-TG distance were 8.7 ± 3.6 mm for NK, 12.1 ± 6.0 mm for PD, and 16.7 ± 4.3 mm in the TD group ( P < .01). The mean values for TT-PCL distance were 18.5 ± 3.6 mm for NK, 18.5 ± 4.5 mm for PD, and 21.2 ± 4.2 mm in the TD group ( P = .03). The mean values for TG-PCL distance were 9.6 ± 3.0 mm for NK, 7.1 ± 3.4 mm for PD, and 5.1 ± 3.3 mm in the dysplastic group ( P < .01). Conclusion: The present results indicate that increased TT-TG distance is due to medialization of the TG and not lateralization of the TT. Knees with TD had increased TT-TG distance compared with the knees of the control group and the knees with PD. The TT-PCL distance did not differ significantly between groups, whereas the TG-PCL distance declined with increased TT-TG.


2021 ◽  
Vol 9 (1) ◽  
pp. 232596712097366
Author(s):  
Zhen-Zhen Dai ◽  
Lin Sha ◽  
Zi-Ming Zhang ◽  
Zhen-Peng Liang ◽  
Hao Li ◽  
...  

Background: The tibial tubercle–trochlear groove (TT-TG) distance was originally described for computed tomography (CT), but it has been measured on magnetic resonance imaging (MRI) in patients with patellar instability (PI). Whether the TT-TG measured on CT versus MRI can be considered equivalent in skeletally immature children remains unclear. Purpose: To investigate in skeletally immature patients (1) the effects of CT versus MRI imaging modality and cartilage versus bony landmarks on consistency of TT-TG measurement, (2) the difference between CT and MRI measurements of the TT-TG, and (3) the difference in TT-TG between patients with and without PI. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We retrospectively identified 24 skeletally immature patients with PI and 24 patients with other knee disorders or injury but without PI. The bony and cartilaginous TT-TG distances on CT and MRI were measured by 2 researchers, and related clinical data were collected. The interrater, interperiod (bony vs cartilaginous), and intermethod (CT vs MRI) reliabilities of TT-TG measurement were assessed with intraclass correlation coefficients. Results: The 48 study patients (19 boys, 29 girls) had a mean age of 11.3 years (range, 7-14 years). TT-TG measurements had excellent interrater reliability and good or excellent interperiod reliability but fair or poor intermethod reliability. TT-TG distance was greater on CT versus MRI (mean difference, 4.07 mm; 95% CI, 2.6-5.5 mm), and cartilaginous distance was greater than bony distance (mean difference, 2.3 mm; 95% CI, 0.79-3.8 mm). The TT-TG measured on CT was found to increase with the femoral width. Patients in the PI group had increased TT-TG distance compared with those in the control group, regardless of landmarks or modality used ( P > .05 for all). Conclusion: For skeletally immature patients, the TT-TG distance could be evaluated on MRI, regardless of whether cartilage or bony landmarks were used. Its value could not be interchanged with CT according to our results; however, further research on this topic is needed.


2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0013
Author(s):  
Alexandra H. Aitchison ◽  
Kenneth M. Lin ◽  
Daniel W. Green

Background: Tibial tubercle to trochlear groove distance (TT-TG) and external tibiofemoral rotation (TFR) through the knee joint have been identified potential contributing factors to patellar instability. In patients with a fixed or obligatory lateral patella dislocation (FOD), the normal force vector of the extensor mechanism is altered, so instead of a direct axial pull to cause extension, it exerts a lateralizing and external rotatory force on the tibia via the tibial tubercle. Hypothesis/Purpose: The purpose of this study is to investigate postoperative changes in TT-TG and TFR after medial patellofemoral ligament reconstruction (MPFLR) in two clinical cohorts: standard traumatic patellar instability (SPI) patients and FOD patients. We hypothesized that by surgically relocating the patella in the trochlea, and re-establishing medial sided soft tissue tension, the increased medializing force vector on the patella may exert enough force to alter resting rotation of the tibia in relation to the femur in the FOD group. Methods: A retrospective study was performed from April 2009 to February 2019. FOD and SPI patients under 18 years with available magnetic resonance imaging (MRI) of the knee before and after MPFLR were eligible. All FOD patients in the time frame were analyzed and SPI patients were randomly selected. Exclusion criteria were outside institution MRI, concomitant alignment procedures done at the time of MPFLR, and prior MPFLR or tibial tubercle osteotomy. TT-TG and TFR (using the posterior femoral and tibial condylar lines) were measured blindly on initial axial MRI. Statistical analysis using a paired sample t-test was performed with significance set at p<0.05. Results: A total of 30 patients were included, 14 in the FOD group and 16 in the SPI group. The mean age at time of surgery was 13.9 years (range 10-17 years), 53% of the cohort was female, and the mean time from surgery to follow-up MRI was 2.0 years. Demographics by group are shown in Table 1. TT-TG and TFR were not significantly different preoperatively versus postoperatively in the SPI group (Table 2). In the FOD group, both TT-TG (17.7 vs 13.7, P=.019) and TFR (8.6 vs 3.1, P=.025) decreased significantly on postoperative MRI. Conclusion: The postoperative decrease in TT-TG and TFR in the FOD group suggests that MPFLR in fixed or obligatory dislocators can improve the external rotation deformity through the level of the joint, and thus may help normalize the forces acting through the extensor mechanism. Tables/ Figures [Table: see text][Table: see text]


Author(s):  
Ian S. MacLean ◽  
Taylor M. Southworth ◽  
Ian J. Dempsey ◽  
Neal B. Naveen ◽  
Hailey P. Huddleston ◽  
...  

AbstractThe tibial tubercle–trochlear groove (TT-TG) distance is currently utilized to evaluate knee alignment in patients with patellar instability. Sagittal plane pathology measured by the sagittal tibial tubercle–trochlear groove (sTT-TG) distance has been described in instability but may also be important to consider in patients with cartilage injury. This study aims to (1) describe interobserver reliability of the sTT-TG distance and (2) characterize the change in the sTT-TG distance with respect to changing knee flexion angles. In this cadaveric study, six nonpaired cadaveric knees underwent magnetic resonance imaging (MRI) studies at each of the following degrees of knee flexion: −5, 0, 5, 10, 15, and 20. The sTT-TG distance was measured on the axial T2 sequence. Four reviewers measured this distance for each cadaver at each flexion angle. Intraclass correlation coefficients were calculated to determine interobserver reliability and reproducibility of the sTT-TG measurement. Analysis of variance (ANOVA) tests and Friedman's tests with a Bonferroni's correction were performed for each cadaver to compare sTT-TG distances at each flexion angle. Significance was defined as p < 0.05. There was excellent interobserver reliability of the sTT-TG distance with all intraclass correlation coefficients >0.9. The tibial tubercle progressively becomes more posterior in relation to the trochlear groove (more negative sTT-TG distance) with increasing knee flexion. The sTT-TG distance is a measurement that is reliable between attending surgeons and across training levels. The sTT-TG distance is affected by small changes in knee flexion angle. Awareness of knee flexion angle on MRI is important when this measurement is utilized by surgeons.


Author(s):  
Aaron Krych ◽  
Christopher Camp ◽  
Jeffrey Bond ◽  
Mark Collins ◽  
Michael Stuart ◽  
...  

2021 ◽  
Author(s):  
Conglei Dong ◽  
Chao Zhao ◽  
Ming Li ◽  
Huijun Kang ◽  
Kang Piao ◽  
...  

Abstract BackgroundThe objective of present study was to investigate the operative effect of patellofemoral arthroplasty combined with the tibial tubercle transfer for isolated patellofemoral arthritis patients with an increased tibial tuberosity-trochlear groove distance (>20mm). MethodsA prospective study was performed between November 2012 and December 2017. Finally, thirty-six cases, with a mean age of 61.1 ± 7.3 years, were admitted to our study. A total of 17 patients underwent patellofemoral arthroplasty combined with tibial tubercle transfer, and 19 patients underwent patellofemoral arthroplasty only. All eligible patients had CT scans preoperatively and at 12 months follow-up, to assess the stability of the patellofemoral joint on axial slices. In addition, the demographic and clinical features of all the patients were asked. Knee balance was assessed with the single leg stance test and timed get up and go, and functionality was evaluated with stair climbing test and the Western Ontario and McMaster Universities Osteoarthritis Index score. (P>0.05) ResultsPreoperatively, the data regarding the knee balance and functionality were not significantly different between the two Groups (P>0.05). Many measurements showed significant differences between the two groups at the last follow-up. Significant differences were seen in well-known measurements such as the SLST (Group I, 28.9 s (SD 7.5); Group II, 20.3 s (SD 5.9); p < 0.001), TGUG (Group I, 13.4 s (SD 3.2); Group II, 16.8 s (SD 3.1); p < 0.001), and SCT (Group I, 18.6 s (SD 6.8); Group II, 24.5 s (SD 8.7); p < 0.001). Additionally, the median WOMAC score was improved from 62.7 (SD 11.2) preoperatively to 25.7 (SD 8.2) one year postoperatively in Group I and from 64.1 (SD 10.7) to 36.2 (SD 9.7) in Group II, which were also significantly different between the groups. ConclusionsFor such special IPA patients with an increased TT-TG (>20mm), the combined operation of PFA combined with TTT can better restore the involutional relationship of patellofemoral joint and further improve the balance and function of knee joint.


2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
David L. Bernholt ◽  
Joseph D. Lamplot ◽  
Andrew M. Block ◽  
Jeffrey J. Nepple

Sign in / Sign up

Export Citation Format

Share Document