Intraobserver and Interobserver Reproducibility of Classifications of Tibial Plateau Fractures and the Surgical Approaches Chosen Comparing 2D CT and 3D Printing: Reliability Study

Two-dimensional and three-dimensional computed tomography for the classification and characterisation of tibial plateau fractures

Classification of tibial plateau fractures using 3DCT with and without subtraction of unfractured bones

To evaluate the interobserver agreement for both treatment plan and fracture classification of tibial plateau fractures using plain radiographs, computed tomography (CT) scan, and magnetic resonance imaging (MRI). Prospective study to assess the impact of an advanced radiographic study on the agreement of treatment plan and fracture classification of tibial plateau fractures among three orthopaedic surgeons. Patients presenting with tibial plateau fractures to a level I trauma center were evaluated with plain knee radiographs (anteroposterior, lateral, two oblique views), CT scan, and MRI. Three experienced attending orthopaedic trauma surgeons were randomly presented three sets of studies for each injury: radiographs alone, radiographs with CT, and radiographs with MRI (including soft tissue injuries documented by an experienced MRI radiologist). The surgeons were asked to render fracture classification and treatment plan based upon the blind reading of each individual radiographic set. Agreement among the three surgeons was measured using kappa coefficients. For fracture classification, radiographs alone yielded a mean kappa coefficient of 0.68, which increased to 0.73 for radiographs with CT scan and 0.85 for radiographs with MRI. Fracture classification (Schatzker) was changed an average of 6% with the addition of the CT scan and 21% based on radiographs with MRI. For the fracture management plan, the mean interobserver kappa coefficient for radiographs alone was 0.72, which increased to 0.77 for radiographs with CT scan and 0.86 for radiographs with MRI. MRI changed treatment plan in 23% of the cases. Magnetic resonance imaging increases the interobserver agreement on fracture classification and operative management of tibial plateau fractures.

PurposeIn this systematic review, we evaluate the effect of radiographs and 2D and 3D imaging techniques on the interobserver agreement of six commonly used classification systems for tibial plateau fractures.MethodsIn accordance with PRISMA guidelines, PubMed, Cochrane, Embase and Web of Science were searched for studies regarding the effect of 2D and 3D imaging techniques on the interobserver agreement of tibial plateau classification systems. Studies validating new classification systems, not providing own data or only providing information on the interobserver agreement for radiographs were excluded. Studies were scored based on the ROBINS-I risk of bias tool.ResultsOur review analysed 14 studies on different classification systems used for tibial plateau fractures in clinical practice, with the Schatzker classification being the most commonly used classification system. The results showed that the addition of 2D CT led to a significant improvement of interobserver agreement for one study. However, other included studies showed varying levels of interobserver agreement, ranging from fair to substantial according to the interpretation by Landis and Koch. The addition of 3D CT resulted in a significant deterioration in one study for the Schatzker classification. Similar to the addition of 2D CT, the interobserver agreement for the Schatzker classification with the addition of 3D CT were heterogeneous ranging from fair to almost perfect according to the interpretation by Landis and Koch.ConclusionsThe use of 2D CT can be recommended for classifying tibial plateau fractures with the Schatzker classification, AO/OTA classification and Hohl classification. The value of 3D CT on the interobserver agreement of commonly used classification systems remains uncertain and unproven. Therefore, we do not recommend the use of 3D CT for the classification of tibial plateau fractures. Overall, the advancement of imaging techniques is not in line with the advancement in interobserver agreement on fracture classification.

PurposeTibial plateau fractures continue to be a challenging task in clinical practice and current outcomes seem to provide the potential for further improvement. Especially presurgical understanding of the orientation of fracture lines and fracture severity is an essential key to sufficient surgical treatment. The object of this study was to evaluate the reliability of modern axial CT-based classification systems for tibial plateau fractures. In addition, the diagnostic-added value of 3D printing on the classification systems was investigated.Methods22 raters were asked to classify 22 tibial plateau fractures (11 AO B- and 11 AO C-fractures) with the AO, the 10-Segment and the Revisited Schatzker classification in a three-step evaluation: first only using CT scans, second with 3D volumetric reconstructions and last with 3D-printed fracture models. Inter- and intraobserver agreement and the subjective certainty were analyzed. Statistics were done using kappa values, percentage match and a univariant one-way analysis of variance.ResultsThe AO classifications interobserver percentage match and kappa values improved for all raters and recorded an overall value of 0.34, respectively, 43% for the 3D print. The 10-Segment classification interobserver agreement also improved with the 3D-printed models and scored an overall kappa value of 0.18 and a percentage match of 79%. Equally the Revisited Schatzker classification increased its values to 0.31 and 35%. The intraobserver agreement showed a moderate agreement for the AO (0.44) and Revisited Schatzker classification (0.42) whereas the 10-Segment classification showed a fair agreement (0.27). Additionally, the raters changed their classification in 36% of the cases after evaluating the fracture with the 3D-printed models and the subjective certainty regarding the decisions improved as categories of self-reliant diagnostic choices were selected 18% (p < 0.05) more often after using the 3D-printed models.ConclusionBased on the measured outcomes it was concluded that the new classification systems show an overall slight to fair reliability and the use of 3D printing proved to be beneficial for the preoperative diagnostics of tibial plateau fractures. The 10-Segment classification system showed the highest percentage match evaluation of all classification systems demonstrating its high clinical value across all levels of user experience.

This study aimed to assess whether three-dimensional (3D) CT imaging improves the inter- and intra-observer reliability of peri-knee fracture classifications, compared to two-dimensional (2D) CT imaging. A retrospective analysis was conducted on 23 patients with peri-knee fractures, using both 2D and 3D-CT scans. Three radiologists classified distal femur, patella, and tibial plateau fractures according to Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) and Schatzker systems. Reliability was measured using Cohen's kappa, with evaluations conducted at two separate intervals to assess intra- and inter-observer consistency. The intra-observer reliability for 2D-CT was substantial for distal femur (ϰ = 0.737, IQR 0.615-0.788) and tibial plateau (ϰ = 0.732, IQR 0.615-0.819) fractures, improving slightly with 3D-CT (ϰ = 0.775, IQR 0.658-0.869; ϰ = 0.768, IQR 0.628-0.882 respectively). Patella fracture classification showed almost perfect reliability (ϰ = 0.823, IQR 0.707-0.882) with 2D-CT, further improving with 3D-CT (ϰ = 0.865, IQR 0.764-0.951). However, inter-observer reliability showed no significant improvement with the addition of 3D-CT across all fracture types. While 3D-CT marginally enhances intra-observer reliability for peri-knee fractures, the difference in inter-observer reliability compared to 2D-CT was not statistically significant.

IntroductionAccurate glenoid component placement is crucial for anatomic (TSA) or reverse (RSA) total shoulder arthroplasty. Preoperative glenoid assessment by using CT scans with or without planning software seems to be the established method to plan implant positions. MRI scans can also display the glenoid bone for preoperative assessment while reducing radiation exposure. Therefore, the objective of this study was to manually assess the glenoid version and inclination in 2D MRI and CT scans in cases with degenerative shoulder pathologies. The results were compared to those of an automated 3D planning software to validate the imaging modality for preoperative glenoid assessment. MethodsMRI and CT scans of 146 patients (n=41 aTSA; n=105 RSA) were included in this retrospective, single-center study. Glenoid version and inclination were measured manually according to Friedman et al and Maurer et al on CT and MRI scans by two observers. Subsequently, the results were compared to the automated measurements performed by a planning software. A repeated-measures analysis of variance (ANOVA) was performed to compare the measured angles and interobserver and intraobserver reliability was calculated using the intraclass correlation coefficients. The level of significance was set p<0.05. ResultsThe average glenoid inclination measured in CT scans was 7.94°±7.33°, in MRI scans 8.56°±7.34° and in automated planning software 7.87°±7.60°. The ANOVA analysis revealed significant differences in mean inclination between 2D MRI and 2D CT (p<0.0005) and between MRI and automated software (p=0.011). No significant difference was found between 2D CT scans and automated planning software (p=1.000). Mean glenoid version measured in 2D CT scans was -7.94°±10.86°, in 2D MRI scans it was -8.04°±10.80° and -8.32°±11.53° by the automated planning software. There was no significant difference in between measurement methods (p = 0.339). Interobserver error analysis showed no statistical differences between the two observers. All measurements had excellent intraobserver reliability. ConclusionPreoperative assessment of glenoid version and inclination is crucial in ensuring precise implant positioning and orientation in TSA and RSA. This study observed a significant level of concordance between manual and automated measuring techniques utilizing MRI and CT scans. Mean glenoid inclination exhibited a statistically significant difference of less than 1° across the assessment modalities and no difference for glenoid version was noted. It seems to be questionable if this finding is clinically relevant. MRI may serve as a viable and safe option for assessing glenoid morphology, version and inclination if CT scans are not available.

Current classifications of tibial plateau fractures include three-pillar classification, four-quadrant classification, eight-segment classification, ten-segment classification, and four-column & nine-segment classification. This article reviews the various CT classifications of tibial plateau fractures, their advantages and disadvantages and surgical approaches as well. The essence of the CT classifications is to pay more attention to the coronary fracture line, especially the posterior coronal fracture fragments. A classification which combines the four-quadrant idea of the articular surface of the tibial plateau with the four-column idea of the peripheral cortex of the tibial plateau, and is supplemented by descriptions of non-articular surface structures (intercondylar spine, tibial tubercle and fibula head), may provide a more comprehensive understanding of a specific tibial plateau fracture, but may therefore be too complicated and difficult to use clinically due to too many combinations that need matching. Key words: Tibial plateau; Fracture; Classification; CT

Intra-articular tibial plateau fracture characteristics according to the “Ten segment classification”

Introduction: Tibial Plateau fractures are complex lesions that require deep understanding of the lesion morphology.Computed tomography (CT) is essential for preoperative planning.Studies have shown clinical benefits in surgical management with the application of 3D models.The aim of the study is to analyze changes in preoperative planning by using 3D printing vs CT. Hypothesis:The use of 3D models generates important changes in preoperative planning of tibial plateau fractures. Material and Method:A descriptive observational study was performed.Patients with Schatzker V and VI tibial plateau fracture were included in the same center, with CT images in the local DICOM system.Patients who did not have a complete set of images or 3D reconstruction were excluded.The models were generated using Meshmixer version 3.5.4software, printing each case using Creality version CR-10 max printer.Preoperative planning surveys were completed by knee surgeons, using 3D models evaluating four variables (number of plates, surgical approach, position of the patient, use of bone graft).The survey was repeated a week later, using the respective CT, anonymizing each case.A descriptive analysis was performed and the intraobserver agreement was calculated by Cohen's Kappa test using Excel 16.70 for each independent variable and then, for each complete case.Results: Ten patients with tibial plateau fractures were evaluated by ten knee surgeons separated in two groups, according to less or more than 10 years of experience (five surgeons in each group).The agreement for the number of plates, surgical approach, position of the patient and use of bone graft, had a kappa value of 0.31, 0.16, 0.53 and 0.49 respectively, obtaining an overall result of 0.37.80% of the cases had at least one change within the 4 variables studied from the use of 3D models with a Kappa Cohen value of 0.The agreement in the group of surgeons with less than 10 years of experience had an average Kappa value of 0.34 and the group with more than 10 years an average of 0.39. Conclusion:The application of 3D models in tibial plateau fractures presents a high rate of changes in preoperative planning, especially in the choice of plate number and surgical approach.

The influence of pre-operative Computed Tomography (CT) on surgical approach and fixation for fractures of the tibial plateau

Background: Various studies have shown the benefit of three-dimensional (3D) computed tomography (CT) reconstruction and especially 3D printing in the treatment of tibial plateau fractures (TPFs). This study aimed to investigate whether mixed-reality visualization (MRV) using mixed-reality glasses can provide a benefit for CT and/or 3D printing in planning treatment strategies for complex TPFs. Methods: Three complex TPFs were selected for the study and processed for 3D imaging. Subsequently, the fractures were presented to specialists in trauma surgery using CT (including 3D CT reconstruction), MRV (hardware: Microsoft HoloLens 2; software: mediCAD MIXED REALITY) and 3D prints. A standardized questionnaire on fracture morphology and treatment strategy was completed after each imaging session. Results: 23 surgeons from 7 hospitals were interviewed. A total of 69.6% (n = 16) of those had treated at least 50 TPFs. A change in fracture classification according to Schatzker was recorded in 7.1% of the cases and in 78.6% an adjustment of the ten-segment classification was observed after MRV. In addition, the intended patient positioning changed in 16.1% of the cases, the surgical approach in 33.9% and osteosynthesis in 39.3%. A total of 82.1% of the participants rated MRV as beneficial compared to CT regarding fracture morphology and treatment planning. An additional benefit of 3D printing was reported in 57.1% of the cases (five-point Likert scale). Conclusions: Preoperative MRV of complex TPFs leads to improved fracture understanding, better treatment strategies and a higher detection rate of fractures in posterior segments, and it thus has the potential to improve patient care and outcomes.

Treatment of complex tibial plateau fractures remains a challenging task in clinical practice. Sufficient and appropriate preoperative decision making is essential for optimal treatment success and ultimately influences patient outcomes. Recently, the novel technique of 3D printing has proven to be beneficial for the preoperative management in other joint regions. To investigate the impact of point-of-care 3D printing on the preoperative management of tibial plateau fractures, we asked 5 students, 10 surgical residents, 3 junior surgeons and 4 senior surgeons, to simulate the preoperative planning of 22 tibial plateau fractures (11 AO B and 11 AO C fractures) regarding the treatment concept, patient positioning, operative approach and implant selection and positioning. First with CT scans only, second with 3D volumetric reconstructions, and finally with 3D printed fracture models. We analyzed the inter- and intraobserver agreement and the subjective perceived confidence of the rater regarding his decision with the different imaging modalities across the different levels of professional experience. Statistics were performed using kappa values, percentage match (PM) analysis and a univariate one-way analysis of variance. The use of 3D printing had no effect on the interobserver reliability of treatment concept selection (PM CT 83% > 3DCT 83% > 3D 82%). However, descriptively higher kappa and percentage match values increased for agreement on patient positioning and surgical approach using 3D printed fracture models. In addition, the raters selected the implants that were actually used to treat the fractures in 63% of the cases. The subjective perceived certainty of the raters increased with the use of 3D printing technology from 45% (CT and 3DCT) to 60% (3D). Additionally, raters changed their treatment plan in 36% of the cases and gained additional information 76% of the time when using the 3D printed specimen. The use of 3D printed fracture models showed a trend toward higher interrater reliability of patient positioning and surgical approach for medical students and surgical residents, while experienced surgeons show less benefit. In addition, 3D-printed models supported implant pre-selection and increased subjective confidence, positively influencing preoperative planning.

BackgroundTibial plateau fractures are often complex, and they can be challenging to treat. Classifying fractures is often part of the treatment process, but intra- and interobserver reliability of fracture classification systems often is inadequate to the task, and classifications that lack reliability can mislead providers and result in harm to patients. Three-dimensionally (3D)-printed models might help in this regard, but whether that is the case for the classification of tibial plateau fractures, and whether the utility of such models might vary by the experience of the individual classifying the fractures, is unknown.Questions/purposes(1) Does the overall interobserver agreement improve when fractures are classified with 3D-printed models compared with conventional radiology? (2) Does interobserver agreement vary among attending and consultant trauma surgeons, senior surgical residents, and junior surgical residents? (3) Do surgeons’ and surgical residents’ confidence and accuracy improve when tibial plateau fractures are classified with an additional 3D model compared with conventional radiology?MethodsBetween 2012 and 2020, 113 patients with tibial plateau fractures were treated at a Level 1 trauma center. Forty-four patients were excluded based on the presence of bone diseases (such as osteoporosis) and the absence of a CT scan. To increase the chance to detect an improvement or deterioration and to prevent observers from losing focus during the classification, we decided to include 40 patients with tibial plateau fractures. Nine trauma surgeons, eight senior surgical residents, and eight junior surgical residents—none of whom underwent any study-specific pretraining—classified these fractures according to three often-used classification systems (Schatzker, OA/OTA, and the Luo three-column concept), with and without 3D-printed models, and they indicated their overall confidence on a 10-point Likert scale, with 0 meaning not confident at all and 10 absolutely certainty. To set the gold standard, a panel of three experienced trauma surgeons who had special expertise in knee surgery and 10 years to 25 years of experience in practice also classified the fractures until consensus was reached. The Fleiss kappa was used to determine interobserver agreement for fracture classification. Differences in confidence in assessing fractures with and without the 3D-printed model were compared using a paired t-test. Accuracy was calculated by comparing the participants’ observations with the gold standard.ResultsThe overall interobserver agreement improved minimally for fracture classification according to two of three classification systems (Schatzker: κconv = 0.514 versus κ3Dprint = 0.539; p = 0.005; AO/OTA:κconv = 0.359 versus κ3Dprint = 0.372; p = 0.03). However, none of the classification systems, even when used by our most experienced group of trauma surgeons, achieved more than moderate interobserver agreement, meaning that a large proportion of fractures were misclassified by at least one observer. Overall, there was no improvement in self-assessed confidence in classifying fractures or accuracy with 3D-printed models; confidence was high (about 7 points on a 10-point scale) as rated by all observers, despite moderate or worse accuracy and interobserver agreementConclusionAlthough 3D-printed models minimally improved the overall interobserver agreement for two of three classification systems, none of the classification systems achieved more than moderate interobserver agreement. This suggests that even with 3D-printed models, many fractures would be misclassified, which could result in misleading communication, inaccurate prognostic assessments, unclear research, and incorrect treatment choices. Therefore, we cannot recommend the use of 3D-printed models in practice and research for classification of tibial plateau fractures.Level of EvidenceLevel III, diagnostic study.

Nearly 20% of Total knee Arthroplasty patients remain dissatisfied. This is a major concern in twenty-first century arthroplasty practice. Accurate implant sizing is shown to improve the implant survival, knee balance and patient reported outcome. Aim of the current study is to assess the efficacy of pre-operative three-dimensional (3D) CT scan templating in a robot-assisted TKA in predicting the correct implant sizes and alignment. Prospectively collected data in a single center from 30 RA-TKAswas assessed. Inclusion criterion was patients with end stage arthritis (both osteoarthritis and rheumatoid arthritis) undergoing primary TKA. Patients undergoing revision TKA and patients not willing to participate in the study were excluded. Preliminary study of ten patients had indicated almost 100% accuracy in determining the implant size and position. Sample size was estimated to be 28 for 90% reduction in implant size and position error with α error of 0.05 and beta error of 0.20 with power of study being 80. Post-operative radiographs were assessed by an independent observer with respect to implant size and position. The accuracy of femoral and tibial component sizing in the study was compared with the historic control with Chi-squared test. The p value < 0.05 was considered significant. The pre-operative CT scan 3D templating accuracy was 100% (30 out of 30 knees) for femoral component and 96.67% (29 out of 30 knees) for tibial component. The implant position and limb alignment was accurate in 100% of patients. The accuracy of femoral component and tibial component sizing is statistically significant (Chi-squared test, p value 0.0105 and 0.0461, respectively). The study results show the effectiveness of pre-operative 3 D CT scan planning in predicting the implant sizes and implant positioning. This may have a potential to improve the implant longevity, clinical outcomes and patient satisfaction.