Surgery for Patellar Instability

Purpose. The aim of the present study was to investigate tibial tuberosity-trochlear groove (TT-TG) distance dynamics in patients with patellofemoral pain (PFP) and pain free individuals by using full weight bearing kinematic magnetic resonance imaging (MRI) And correlation with patellar instability. Materials and methods. 51 female individuals with PFP and 26 pain free female individuals participated in the study. The kinematic MRI was performed with 1,5 T MRI unit and full-weight bearing. TT-TG distance, bissect offset (BSO) and patellar tilt angle (PTA) were measured in steps of 10° between 50° of flexion to full extension. Results. The TT–TG was higher in PFP patients compared to volunteers’ from 40° to full extension. This difference was statistically significant (p<0.01). PFP patients demonstrated statistically significantly greater TT-TG distance increase from 30° to full extension. BSO and PTA were moderately correlated to TT-TG from 20° of flexion to full extension. Conclusion. TT-TG distance is dynamic and increases significantly during extension in patients with PFP and pain free individuals, depending on knee flexion angle. It shows different pattern of dynamics in PFP group. TT-TG distance is associated with patellar instability (BSO and PTA) at low degrees of flexion.

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Comparing the Tibial Tuberosity–Trochlear Groove Distance Between CT and MRI in Skeletally Immature Patients With and Without Patellar Instability

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967120973665 ◽

2021 ◽

Vol 9 (1) ◽

pp. 232596712097366

Author(s):

Zhen-Zhen Dai ◽

Lin Sha ◽

Zi-Ming Zhang ◽

Zhen-Peng Liang ◽

Hao Li ◽

...

Keyword(s):

Patellar Instability ◽

Intraclass Correlation ◽

Mean Difference ◽

Tibial Tubercle ◽

Control Group ◽

Trochlear Groove ◽

Skeletally Immature ◽

Bony Landmarks ◽

The Difference ◽

Ct And Mri

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.

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Decreasing Thickness of Partial Lateral Trochlear Cartilage in Patients with Patellar Instability

Orthopaedic Surgery ◽

10.1111/os.12971 ◽

2021 ◽

Author(s):

Chongyi Fan ◽

Ming Li ◽

Guangmin Yang ◽

Xunkai Feng ◽

Fei Wang

Keyword(s):

Patellar Instability

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Early patellofemoral articular cartilage degeneration in a rat model of patellar instability is associated with activation of the NF-κB signaling pathway

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-03965-8 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Wei Lin ◽

Huijun Kang ◽

Yike Dai ◽

Yingzhen Niu ◽

Guangmin Yang ◽

...

Keyword(s):

Articular Cartilage ◽

Signaling Pathway ◽

Subchondral Bone ◽

Patellofemoral Joint ◽

Patellar Instability ◽

Cartilage Degeneration ◽

Control Group ◽

And Control ◽

Articular Cartilage Degeneration ◽

And Cartilage

Abstract Background Patellar instability (PI) often increases the possibility of lateral patellar dislocation and early osteoarthritis. The molecular mechanism of early articular cartilage degeneration during patellofemoral osteoarthritis (PFOA) still requires further investigation. However, it is known that the NF-κB signaling pathway plays an important role in articular cartilage degeneration. The aim of this study was to investigate the relationship between the NF-κB signaling pathway and patellofemoral joint cartilage degeneration. Methods We established a rat model of PI-induced PFOA. Female 4-week-old Sprague-Dawley rats (n = 120) were randomly divided into two groups: the PI (n = 60) and control group (n = 60). The distal femurs of the PI and control group were isolated and compared 4, 8, and 12 weeks after surgery. The morphological structure of the trochlear cartilage and subchondral bone were evaluated by micro-computed tomography and histology. The expression of NF-κB, matrix metalloproteinase (MMP)-13, collagen X, and TNF-ɑ were evaluated by immunohistochemistry and quantitative polymerase chain reaction. Results In the PI group, subchondral bone loss and cartilage degeneration were found 4 weeks after surgery. Compared with the control group, the protein and mRNA expression of NF-κB and TNF-ɑ were significantly increased 4, 8, and 12 weeks after surgery in the PI group. In addition, the markers of cartilage degeneration MMP-13 and collagen X were more highly expressed in the PI group compared with the control group at different time points after surgery. Conclusions This study has demonstrated that early patellofemoral joint cartilage degeneration can be caused by PI in growing rats, accompanied by significant subchondral bone loss and cartilage degeneration. In addition, the degeneration of articular cartilage may be associated with the activation of the NF-κB signaling pathway and can deteriorate with time as a result of PI.

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Relationship between Anatomical Risk Factors, Articular Cartilage Lesions, and Patient Outcomes Following Medial Patellofemoral Ligament Reconstruction

Cartilage ◽

10.1177/1947603519894728 ◽

2019 ◽

pp. 194760351989472 ◽

Cited By ~ 4

Author(s):

Charles L. Holliday ◽

Laurie A. Hiemstra ◽

Sarah Kerslake ◽

John A. Grant

Keyword(s):

Risk Factors ◽

Odds Ratio ◽

Patellar Instability ◽

Ligament Reconstruction ◽

Medial Patellofemoral Ligament ◽

Trochlear Dysplasia ◽

Cartilage Lesion ◽

Low Grade ◽

Medial Patellofemoral Ligament Reconstruction ◽

Cartilage Lesions

Objective The purpose of this study was (1) to determine which risk factors for patellar instability were associated with the presence of patellofemoral cartilage lesions and (2) to determine how cartilage lesion presence, size, and grade affect postoperative disease-specific quality of life. Design Preoperative, intraoperative, and postoperative demographic, anthropometric (body mass index, Beighton score, hip rotation), radiographic (crossover sign, trochlear bump), cartilage lesion morphology (presence, size, location, grade), and outcomes data (Banff Patella Instability Instrument 2.0 [BPII 2.0]) were prospectively collected from patients undergoing isolated medial patellofemoral ligament reconstruction. For all knees ( n = 264), single and multivariable logistic regression was used to determine if any patellar instability risk factors affected the odds of having a cartilage lesion. In patients with unilateral symptoms ( n = 121), single variable linear regression was used to determine if the presence, size, or ICRS (International Cartilage Regeneration & Joint Preservation Society) grade of cartilage lesions could predict the 12 or 24+ month postoperative BPII 2.0 score. Results A total of 84.5% of knees had patellofemoral cartilage lesions (88.3% involved the distal-medial patella). Trochlear dysplasia (high grade: odds ratio = 15.7, P < 0.001; low grade: odds ratio = 2.9, P = 0.015) was associated with the presence of a cartilage lesion. The presence, size, and grade of cartilage lesions were not associated with 12 or 24+ month postoperative BPII 2.0 scores. Conclusions Trochlear dysplasia was a risk factor for the development of patellofemoral cartilage lesions in this patient population. Cartilage lesions most commonly involve the distal-medial patella. There was no significant relationship between patellofemoral cartilage lesion presence, size, or grade and postoperative BPII 2.0 scores in short-term follow-up.

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Axial MRI index of patellar engagement: A new method to assess patellar instability

Orthopaedics & Traumatology Surgery & Research ◽

10.1016/j.otsr.2013.10.006 ◽

2013 ◽

Vol 99 (8) ◽

pp. S399-S405 ◽

Cited By ~ 24

Author(s):

S. Guilbert ◽

V. Chassaing ◽

C. Radier ◽

C. Hulet ◽

F. Rémy ◽

...

Keyword(s):

Patellar Instability ◽

New Method

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Are metric parameters sufficient alone in evaluation of the patellar instability? New angular measuring parameters

Journal of Orthopaedic Surgery ◽

10.1177/2309499016684498 ◽

2017 ◽

Vol 25 (1) ◽

pp. 230949901668449 ◽

Cited By ~ 1

Author(s):

Alper Deveci ◽

Deniz Cankaya ◽

Serdar Yilmaz ◽

Ersin Celen ◽

Bulent Sakman ◽

...

Keyword(s):

Statistical Analysis ◽

Strong Correlation ◽

Patellar Instability ◽

Pearson Correlation ◽

Trochlear Groove ◽

Rotational Movement ◽

Pearson Correlation Test ◽

Angular Measuring ◽

Metric Measurement ◽

Tibia Shaft

Purposes: When the evaluation of patellar instability is examined from the aspect of the conical-cylindrical anatomy of the tibia, metric measurement parameters such as the tuberositas tibia (TT)–trochlear groove (TG) and patellar tendon (PT) insertion–trochlear groove (TG) distances are not sufficient. We asked whether defined angular parameters reveal the rotational movement of the tuberositas tibia on the tibia shaft, additional to the metric parameters and there is a correlation between the metric and angular parameters. Methods: 19 patients with patellar instability and 22 patients without patellar instability were evaluated. For all patients, two angle and three length parameters were evaluated on the slices taken. Evaluations were made of the TT-TG, the midpoint of the PT insertion-TG distances, the anatomic midpoint of the dome of the TT-TG, the TG-PT angle, and the TG-dome angle (DA). The Pearson correlation test was used for the statistical analysis of correlations between groups. Results: A statistically significant increase was determined in the patellar instability group in the TG-DA and TG-PT angle values compared to the group without patellar instability ( p < 0.05). In both groups, a positive and strong correlation was determined between the TT-TG and the TG-PT and dome of the TT-TG distances, but no statistically significant correlation was determined between the tuberositas TT-TG and TG-PT angle and TG-DA. Conclusion: Metric parameters may not be sufficient alone in the evaluation of patellar instability. Metric parameters should be supported by additional angular parameters which reveal the rotational movement of the TT on the tibia shaft.

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SPONTANEOUS CORRECTION OF EXTERNAL TIBIOFEMORAL ROTATION AND TIBIAL TUBEROSITY-TROCHLEAR GROOVE DISTANCE OCCURS AFTER MEDIAL PATELLOFEMORAL LIGAMENT RECONSTRUCTION IN FIXED OR OBLIGATORY DISLOCATORS

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121s00132 ◽

2021 ◽

Vol 9 (7_suppl3) ◽

pp. 2325967121S0013

Author(s):

Alexandra H. Aitchison ◽

Kenneth M. Lin ◽

Daniel W. Green

Keyword(s):

Patellar Instability ◽

Ligament Reconstruction ◽

Medial Patellofemoral Ligament ◽

Extensor Mechanism ◽

Tibial Tubercle ◽

Trochlear Groove ◽

Medial Patellofemoral Ligament Reconstruction ◽

Force Vector ◽

Tibiofemoral Rotation ◽

The Mean

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]

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