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Matthias J. Feucht - One of the best experts on this subject based on the ideXlab platform.

  • Increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Philipp W. Winkler, Patricia M Lutz, Marco C Rupp, Floria Imhoff, Kaywa Izadpanah, Andreas Imhoff, Matthias J. Feucht
    Abstract:

    Purpose To perform a segmental Analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity. Methods Patients with chronic PFI who underwent Torsional Analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental Analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT ( 35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances. Results Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p  

  • The complexity of bony malalignment in patellofemoral disorders: femoral and tibial torsion, trochlear dysplasia, TT–TG distance, and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    Purpose Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. Methods Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip–knee–ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity–trochlear groove (TT–TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. Results A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p  

  • the complexity of bony malalignment in patellofemoral disorders femoral and tibial torsion trochlear dysplasia tt tg distance and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    PURPOSE Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. METHODS Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip-knee-ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity-trochlear groove (TT-TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. RESULTS A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p < 0.001) and significantly higher values for TT-TG distance (low grade: 19.0 mm ± 5.0 mm, high grade: 21.9 mm ± 5.4 mm; p = 0.002). No significant difference was found for age, tibial torsion, and frontal mechanical axis. With regard to gender, female patients had higher values for femoral torsion (female: 15.6° ± 11.3°, male: 11.0° ± 12.7°; p = 0.044). The correlation Analysis found significant correlation between femoral torsion and tibial torsion (r = 0.244, p = 0.003), femoral torsion and TT-TG distance (r = 0.328, p < 0.001), femoral torsion and frontal mechanical axis (r = 0.291, p < 0.001), and tibial torsion and TT-TG distance (r = 0.182, p = 0.026). CONCLUSION Bony malalignment in patients with patellofemoral disorder is a complex problem given the significant correlation between femoral and tibial torsion, trochlear dysplasia, TT-TG distance, and frontal mechanical axis. Advanced imaging to analyze rotational and frontal plane alignment is recommended in patients with trochlear dysplasia and/or increased TT-TG on standard radiographs and knee MRI. Understanding of the bony pathology in patellofemoral disorders is key to improve the therapeutic and surgical decision. LEVEL OF EVIDENCE III, retrospective cohort study.

Floria Imhoff - One of the best experts on this subject based on the ideXlab platform.

  • increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Philipp W Winkle, Patricia M Lutz, Marco C Rupp, Floria Imhoff, Kaywa Izadpanah, Andreas Imhoff, Matthias J Feuch
    Abstract:

    PURPOSE To perform a segmental Analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity. METHODS Patients with chronic PFI who underwent Torsional Analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental Analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT (  35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances. RESULTS Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p < 0.001), whereas no difference was found for PTT ( - 13° ± 6° vs.  - 12° ± 6°; n.s.). Furthermore, a significant correlation was found between TTT and DTT (p < 0.001), whereas no correlation was found between TTT and PTT (n.s). With regard to TT-TG and TT-PCL distances, no significant differences were observed between the two groups (TT-TG: 15 ± 6 vs. 14 ± 4 mm, n.s.; TT-PCL: 22 ± 4 vs. 21 ± 5 mm, n.s.) and no correlation was found with TTT, DTT, or PTT (n.s.). CONCLUSION In patients with chronic PFI, increased external TTT of greater than 35° is an infratuberositary deformity and does not correlate with a lateralized position of the tibial tuberosity. LEVEL OF EVIDENCE Level III.

  • Increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Philipp W. Winkler, Patricia M Lutz, Marco C Rupp, Floria Imhoff, Kaywa Izadpanah, Andreas Imhoff, Matthias J. Feucht
    Abstract:

    Purpose To perform a segmental Analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity. Methods Patients with chronic PFI who underwent Torsional Analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental Analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT ( 35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances. Results Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p  

  • The complexity of bony malalignment in patellofemoral disorders: femoral and tibial torsion, trochlear dysplasia, TT–TG distance, and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    Purpose Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. Methods Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip–knee–ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity–trochlear groove (TT–TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. Results A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p  

  • the complexity of bony malalignment in patellofemoral disorders femoral and tibial torsion trochlear dysplasia tt tg distance and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    PURPOSE Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. METHODS Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip-knee-ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity-trochlear groove (TT-TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. RESULTS A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p < 0.001) and significantly higher values for TT-TG distance (low grade: 19.0 mm ± 5.0 mm, high grade: 21.9 mm ± 5.4 mm; p = 0.002). No significant difference was found for age, tibial torsion, and frontal mechanical axis. With regard to gender, female patients had higher values for femoral torsion (female: 15.6° ± 11.3°, male: 11.0° ± 12.7°; p = 0.044). The correlation Analysis found significant correlation between femoral torsion and tibial torsion (r = 0.244, p = 0.003), femoral torsion and TT-TG distance (r = 0.328, p < 0.001), femoral torsion and frontal mechanical axis (r = 0.291, p < 0.001), and tibial torsion and TT-TG distance (r = 0.182, p = 0.026). CONCLUSION Bony malalignment in patients with patellofemoral disorder is a complex problem given the significant correlation between femoral and tibial torsion, trochlear dysplasia, TT-TG distance, and frontal mechanical axis. Advanced imaging to analyze rotational and frontal plane alignment is recommended in patients with trochlear dysplasia and/or increased TT-TG on standard radiographs and knee MRI. Understanding of the bony pathology in patellofemoral disorders is key to improve the therapeutic and surgical decision. LEVEL OF EVIDENCE III, retrospective cohort study.

Andreas Imhoff - One of the best experts on this subject based on the ideXlab platform.

  • increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Philipp W Winkle, Patricia M Lutz, Marco C Rupp, Floria Imhoff, Kaywa Izadpanah, Andreas Imhoff, Matthias J Feuch
    Abstract:

    PURPOSE To perform a segmental Analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity. METHODS Patients with chronic PFI who underwent Torsional Analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental Analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT (  35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances. RESULTS Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p < 0.001), whereas no difference was found for PTT ( - 13° ± 6° vs.  - 12° ± 6°; n.s.). Furthermore, a significant correlation was found between TTT and DTT (p < 0.001), whereas no correlation was found between TTT and PTT (n.s). With regard to TT-TG and TT-PCL distances, no significant differences were observed between the two groups (TT-TG: 15 ± 6 vs. 14 ± 4 mm, n.s.; TT-PCL: 22 ± 4 vs. 21 ± 5 mm, n.s.) and no correlation was found with TTT, DTT, or PTT (n.s.). CONCLUSION In patients with chronic PFI, increased external TTT of greater than 35° is an infratuberositary deformity and does not correlate with a lateralized position of the tibial tuberosity. LEVEL OF EVIDENCE Level III.

  • Increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Philipp W. Winkler, Patricia M Lutz, Marco C Rupp, Floria Imhoff, Kaywa Izadpanah, Andreas Imhoff, Matthias J. Feucht
    Abstract:

    Purpose To perform a segmental Analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity. Methods Patients with chronic PFI who underwent Torsional Analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental Analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT ( 35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances. Results Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p  

  • The complexity of bony malalignment in patellofemoral disorders: femoral and tibial torsion, trochlear dysplasia, TT–TG distance, and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    Purpose Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. Methods Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip–knee–ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity–trochlear groove (TT–TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. Results A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p  

  • the complexity of bony malalignment in patellofemoral disorders femoral and tibial torsion trochlear dysplasia tt tg distance and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    PURPOSE Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. METHODS Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip-knee-ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity-trochlear groove (TT-TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. RESULTS A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p < 0.001) and significantly higher values for TT-TG distance (low grade: 19.0 mm ± 5.0 mm, high grade: 21.9 mm ± 5.4 mm; p = 0.002). No significant difference was found for age, tibial torsion, and frontal mechanical axis. With regard to gender, female patients had higher values for femoral torsion (female: 15.6° ± 11.3°, male: 11.0° ± 12.7°; p = 0.044). The correlation Analysis found significant correlation between femoral torsion and tibial torsion (r = 0.244, p = 0.003), femoral torsion and TT-TG distance (r = 0.328, p < 0.001), femoral torsion and frontal mechanical axis (r = 0.291, p < 0.001), and tibial torsion and TT-TG distance (r = 0.182, p = 0.026). CONCLUSION Bony malalignment in patients with patellofemoral disorder is a complex problem given the significant correlation between femoral and tibial torsion, trochlear dysplasia, TT-TG distance, and frontal mechanical axis. Advanced imaging to analyze rotational and frontal plane alignment is recommended in patients with trochlear dysplasia and/or increased TT-TG on standard radiographs and knee MRI. Understanding of the bony pathology in patellofemoral disorders is key to improve the therapeutic and surgical decision. LEVEL OF EVIDENCE III, retrospective cohort study.

Matthias J Feuch - One of the best experts on this subject based on the ideXlab platform.

  • increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Philipp W Winkle, Patricia M Lutz, Marco C Rupp, Floria Imhoff, Kaywa Izadpanah, Andreas Imhoff, Matthias J Feuch
    Abstract:

    PURPOSE To perform a segmental Analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity. METHODS Patients with chronic PFI who underwent Torsional Analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental Analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT (  35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances. RESULTS Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p < 0.001), whereas no difference was found for PTT ( - 13° ± 6° vs.  - 12° ± 6°; n.s.). Furthermore, a significant correlation was found between TTT and DTT (p < 0.001), whereas no correlation was found between TTT and PTT (n.s). With regard to TT-TG and TT-PCL distances, no significant differences were observed between the two groups (TT-TG: 15 ± 6 vs. 14 ± 4 mm, n.s.; TT-PCL: 22 ± 4 vs. 21 ± 5 mm, n.s.) and no correlation was found with TTT, DTT, or PTT (n.s.). CONCLUSION In patients with chronic PFI, increased external TTT of greater than 35° is an infratuberositary deformity and does not correlate with a lateralized position of the tibial tuberosity. LEVEL OF EVIDENCE Level III.

Lukas N. Muench - One of the best experts on this subject based on the ideXlab platform.

  • The complexity of bony malalignment in patellofemoral disorders: femoral and tibial torsion, trochlear dysplasia, TT–TG distance, and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    Purpose Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. Methods Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip–knee–ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity–trochlear groove (TT–TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. Results A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p  

  • the complexity of bony malalignment in patellofemoral disorders femoral and tibial torsion trochlear dysplasia tt tg distance and frontal mechanical axis correlate with each other
    Knee Surgery Sports Traumatology Arthroscopy, 2020
    Co-Authors: Floria Imhoff, Andreas Imhoff, Victor Funke, Lukas N. Muench, Andreas Sauter, Maximilian Englmaier, Klaus Woertler, Matthias J. Feucht
    Abstract:

    PURPOSE Several anatomic risk factors associated with patellofemoral disorders have been described. The purpose of this study was to analyze the relationship between bony parameters commonly used to analyze and define patellofemoral malalignment. METHODS Patients with patellofemoral disorders presenting between 2016 and 2018 who underwent a standardized radiographic workup including conventional radiographs, weight bearing full-leg radiographs, magnetic resonance imaging (MRI) of the knee, and Torsional Analysis using hip-knee-ankle MRI were initially included. Patients with a history of lower extremity fracture and a history of surgical procedures affecting bony alignment or partial/total arthroplasty were subsequently excluded. Radiographs and MRI of all included patients were analyzed by four independent observers. Parameters of interest were: femoral torsion, tibial torsion, trochlear dysplasia, tibial tuberosity-trochlear groove (TT-TG) distance, and frontal mechanical axis. All parameters were compared between patients with low grade and high grade trochlear dysplasia as well as between female and male patients. Correlation of continuous variables was assessed with the Pearson correlation coefficient. A binary logistic regression model was used for the calculation of odds ratio between different parameters. Interclass correlation coefficients (ICC) were calculated to determine the interobserver reproducibility. RESULTS A total of 151 patients could be included for detailed Analysis. Group comparison revealed that patients with high grade trochlear dysplasia showed significantly higher values for femoral torsion (low grade: 9.8° ± 11.0°, high grade: 16.8° ± 11.5°; p < 0.001) and significantly higher values for TT-TG distance (low grade: 19.0 mm ± 5.0 mm, high grade: 21.9 mm ± 5.4 mm; p = 0.002). No significant difference was found for age, tibial torsion, and frontal mechanical axis. With regard to gender, female patients had higher values for femoral torsion (female: 15.6° ± 11.3°, male: 11.0° ± 12.7°; p = 0.044). The correlation Analysis found significant correlation between femoral torsion and tibial torsion (r = 0.244, p = 0.003), femoral torsion and TT-TG distance (r = 0.328, p < 0.001), femoral torsion and frontal mechanical axis (r = 0.291, p < 0.001), and tibial torsion and TT-TG distance (r = 0.182, p = 0.026). CONCLUSION Bony malalignment in patients with patellofemoral disorder is a complex problem given the significant correlation between femoral and tibial torsion, trochlear dysplasia, TT-TG distance, and frontal mechanical axis. Advanced imaging to analyze rotational and frontal plane alignment is recommended in patients with trochlear dysplasia and/or increased TT-TG on standard radiographs and knee MRI. Understanding of the bony pathology in patellofemoral disorders is key to improve the therapeutic and surgical decision. LEVEL OF EVIDENCE III, retrospective cohort study.