The influence of 3D printing on inter- and intrarater reliability on the classification of tibial plateau fractures

[3D printing/implants in traumatology]

The use of 3D printing offers numerous application possibilities in traumatology, including anatomic models, repositioning and drilling guides as well as patient-specific implants. The greatest challenge lies in the rapid availability as many procedures require an immediate intervention. Anatomic models support surgical planning by complementing visual impressions with tactile ones. Printed models not only help in the establishment of surgical strategies but also enhance patient clarification. Studies demonstrate that these models significantly reduce the operating time, duration of fluoroscopy and blood loss, particularly for joint fractures. Repositioning and drilling guides simplify complex procedures and improve outcomes; however, they require precise planning and critical evaluation by the surgeon. Intraoperative guides are helpful, for instance, in accurately placing screws, especially in difficult to access areas or in metaphyseal fractures lacking clear references. Individualized implants play a lesser role in acute care but are useful for posttraumatic defects or corrective osteotomy. In the conservative segment, such as customized splints, 3D printing is being tested but with mixed results. Key requirements for 3D printing in traumatology include high-resolution computed tomography (CT), precise data processing and swift production. Regulatory hurdles and lack of reimbursement currently limit the widespread use. An optimized collaboration between technology and medicine, along with standardized processes, are essential for effectively integrating this technology into practice.

The Use of 3D Printing as an Educational Tool in Orthopaedics

Background

Three-dimensional (3D) printing has proven to be effective in orthopaedic surgery, improving both surgical planning and outcomes. Despite its increasing use in surgical programs, reviews evaluating its educational impact are sparse. Therefore, the aim of this review was to provide educators with evidence-based findings on 3D printing's potential in training junior surgeons, as well as discuss its benefits in enhancing patient communication.

Methods

A comprehensive search using PubMed and Web of Science databases was performed to identify articles related to orthopaedics, 3D printing, and education. After removing duplicates, 2,160 articles were screened, 152 underwent full-text review, and 50 met inclusion criteria. Articles discussed the impact of 3D-printed models on comprehension or surgical performance. Data on publication details, sample size, teaching focus, learning outcomes, costs, and conclusions were extracted. Learning effects in the control (didactic) and experimental (3DP) groups were compared.

Results

In fracture management training, studies demonstrated significantly improved fracture classification accuracy, surgical performance, and interobserver classification agreement with 3D models compared with didactic learning and traditional imaging modalities. These benefits were particularly evident in cases of complex fractures and junior trainees. In arthroscopy, 3D-printed simulators improved procedural accuracy and were more cost-effective than virtual reality simulators and cadaveric laboratory results. Three-dimensionally printed simulators were also assessed for skills related to spine surgery, in which trainees demonstrated clear learning curve improvements for pedicle screw placement and osteotomy techniques, as well as a better understanding of vital paraspinal structures. The application of 3D printing in patient education was equally promising, as it facilitated the process of informed consent, ultimately promoting shared decision making.

Conclusion

The use of 3D-printed models offers effective and customizable methods for developing essential surgical skills. Future research should focus on larger, more diverse study populations and should include long-term follow-up to better assess the impact of 3D printing on education and patient outcomes.

Assessment of proximal tibial fractures with 3D FRACTURE (fast field echo resembling a CT using restricted echo-spacing) MRI-intra-individual comparison with CT

OBJECTIVES

To evaluate the feasibility and diagnostic performance of a 3D FRACTURE (fast field echo resembling a CT using restricted echo-spacing) MRI sequence for the detection and classification of proximal tibial fractures compared with CT.

METHODS

We retrospectively included 126 patients (85 male; 39.6 ± 14.5 years) from two centers following acute knee injury. Patients underwent knee MRI at 3 T including FRACTURE-MRI. Additional CT was performed in patients with tibial fractures (32.5%; n = 41) as the reference standard for fracture classification. Two radiologists independently evaluated FRACTURE-MRI for the presence of fractures and classified them according to AO/OTA, Schatzker, and the 10-segment classification. Diagnostic performance of FRACTURE-MRI was assessed using crosstabulations. Inter-reader agreement was estimated using Krippendorff's alpha. Image quality was graded on a five-point scale (5 = excellent; 1 = inadequate definition of fracture lines and fracture displacement) and assessed using estimated marginal means.

RESULTS

Fractures were detected by FRACTURE-MRI with a sensitivity of 91.5% (83.2-96.5%) and a specificity of 97.1% (93.3-99.0%). Regarding fracture classification, diagnostic performances were slightly lower, with the 10-segment classification yielding the best sensitivity of 85.7% (81.4-89.3%) and specificity of 97.4% (96.6-98.0%), and the Schatzker classification yielding the lowest sensitivity of 78.2% (67.4-86.8%) and specificity of 97.7% (94.1-99.4%). Inter-reader agreement across the whole cohort was excellent (Krippendorff's alpha 0.89-0.96) and when considering only patients with fractures, good to acceptable (0.48-0.91). Image quality was rated good (estimated marginal mean 4.3 (4.1-4.4)).

CONCLUSION

FRACTURE-MRI is feasible at 3 T enabling accurate delineation of fracture lines for precise diagnosis and classification of proximal tibial fractures.

KEY POINTS

Question CT-like MRI is increasingly being evaluated for its advantages in bone imaging but is not yet established in routine practice. Findings The 3D FRACTURE (fast field echo resembling a CT using restricted echo-spacing) MRI sequence is feasible at 3 T, allowing for diagnosis and classification of proximal tibial fractures. Clinical relevance FRACTURE-MRI might be a helpful alternative to computed tomography in an acute trauma setting by reducing costs and radiation exposure in patients requiring a preoperative MRI anyway.

Lack of standardisation in the management of complex tibial plateau fractures: a multicentre experience

OBJECTIVE

In recent years, the trauma mechanisms and fracture types in tibial plateau fractures (TPF) have changed. At the same time, treatment strategies have expanded with the establishment of new classification systems, extension of diagnostics and surgical strategies. Evidence-based recommendations for treatment strategies are rare. The aim of this study is to assess the extent of standardization in the treatment of complex TPF.

MATERIAL AND METHODS

For the study, specialists in trauma surgery/orthopaedics were presented thin-slice CT data sets of three complex TPFs including 3D reconstructions. A standardized questionnaire on fracture morphology and planned treatment strategy was then completed.

RESULTS

A total of 23 surgeons from 7 hospitals (Trauma center levels I-III) were included. All three fractures were most frequently classified as Schatzker type V (fracture I: 52.2%, II: 56.5%, III: 60%). Averaged over all three fractures, 55% of the respondents chose the same patient positioning. The combination of a posteromedial and anterolateral approach was the most frequently chosen approach at 42.7%. Double plating was favored for the surgical treatment of all fractures (70.7%). Preoperative MRI, extended approaches and intraoperative fraturoscopy were significantly more common in level I trauma centres.

CONCLUSION

There are major differences in the management of complex TPF. 360° treatment is carried out in all departments regardless of the level of care, but without further standardization in terms of preoperative imaging, classification, initial treatment, approach, fixation and intraoperative imaging. There are major differences within the departments with different level of care.

Intrarater and Inter-rater Reliability of Tibial Plateau Fracture Classifications: Systematic Review and Meta-Analysis

Background

The interobserver and intraobserver reliability of various tibial plateau fracture (TPF) classifications has been examined in recent literature using radiography, computed tomography, and magnetic resonance imaging. The question remains as to which classification system provides the highest reliability. In this systematic review, we are going to evaluate the overall interobserver and intraobserver reliability of various TPF classifications in different imaging modalities.

Methods

We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In February 2023, predefined terms were used for database search (Embase, PubMed, Scopus, Cochrane, and Web of Science). Meta-analysis of intrarater and inter-rater kappa coefficients was performed for each of the classifications in each modality.

Results

Thirty-four studies were included in this review. Schatzker's classification was more frequently used than others. It had a better intrarater kappa coefficient than the Hohl and Moore and Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association (AO/OTA) classifications in radiography (κ = 0.72, 95% confidence interval [CI] = 0.67-0.76, p < 0.01). The Schatzker and AO/OTA classifications had similar inter-rater reliability in the radiography modality (κ = 0.53, 95% CI = 0.51-0.54, p < 0.01; κ = 0.53, 95% CI = 0.5-0.55, p < 0.01; respectively). In 3-dimensional computed tomography, the Luo classification system showed the highest intrarater (κ = 0.85, 95% CI = 0.35-0.66) and inter-rater (κ = 0.77, 95% CI = 0.73-0.81) kappa coefficients.

Conclusion

Three-column classification proposed by Luo et al. was able to reach the highest degree and was the only classification with near-excellent inter-rater reliability.

Mayo classification of olecranon fractures revisited - Assessment of intra- and interobserver reliability based on CT scans

Purpose

Olecranon fractures are classified using the commonly accepted Mayo classification. Its reliability has been analyzed by means of radiographs. A CT scan is often obtained due to joint involvement. Purpose of this study was to evaluate the intra- and interobserver reliability of the Mayo classification based on CT examination.

Methods

Radiographic and CT images of 20 olecranon fractures were classified by four surgeons at two time points 30 days apart. Intra- and interobserver reliability were assessed using kappa coefficients.

Results

Mean intraobserver reliability between X-rays was substantial and between CTs almost perfect (0.76 and 0.82, respectively). Mean interobserver reliability was fair for X-rays and moderate for CTs (0.32 and 0.44, respectively).

Conclusion

Despite the more detailed imaging compared with radiography only moderate interobserver reliability was found for the classification of olecranon fractures based on CT imaging. This might lead to inconsistent fracture classification in both scientific and clinical setting.

Comparison of virtual reality and computed tomography in the preoperative planning of complex tibial plateau fractures

INTRODUCTION

Preoperative planning is a critical step in the success of any complex surgery. The pur-pose of this study is to evaluate the advantage of VR glasses in surgical planning of complex tibial plateau fractures compared to CT planning.

MATERIALS AND METHODS

Five orthopedic surgeons performed preoperative planning for 30 fractures using either conventional CT slices or VR visualization with a VR headset. Planning was performed in a randomized order with a 3-month interval between planning sessions. A standardized questionnaire assessed planned operative time, planning time, fracture classification and understanding, and surgeons' subjective confidence in surgical planning.

RESULTS

The mean planned operative time of 156 (SD 47) minutes was significantly lower (p < 0.001) in the VR group than in the CT group (172 min; SD 44). The mean planning time in the VR group was 3.48 min (SD 2.4), 17% longer than in the CT group (2.98 min, SD 1.9; p = 0.027). Relevant parameters influencing planning time were surgeon experience (-0.61 min) and estimated complexity of fracture treatment (+ 0.65 min).

CONCLUSION

The use of virtual reality for surgical planning of complex tibial plateau fractures resulted in significantly shorter planned operative time, while planning time was longer compared to CT planning. After VR planning, more surgeons felt (very) well prepared for surgery.

The Clinical Efficacy of Contouring Periarticular Plates on a 3D Printed Bone Model

We report our experience of preoperative plate contouring for periarticular fractures using three-dimensional printing (3DP) technology and describe its benefits. We enrolled 34 patients, including 11 with humerus midshaft fractures, 12 with tibia plateau fractures, 2 with pilon fractures, and 9 with acetabulum fractures. The entire process of plate contouring over the 3DP model was videotaped and retrospectively analyzed. The total time and number of trials for the intraoperative positioning of precontoured plates and any further intraoperative contouring events were prospectively recorded. The mismatch between the planned and postoperative plate positions was evaluated. The average plate contouring time was 9.2 min for humerus shaft, 13.8 min for tibia plateau fractures, 8.8 min for pilon fractures, and 11.6 min for acetabular fractures. Most precontoured plates (88%, 30/34) could sit on the planned position without mismatch. In addition, only one patient with humerus shaft fracture required additional intraoperative contouring. Preoperative patient specific periarticular plate contouring using a 3DP model is a simple and efficient method that may alleviate the surgical challenges involved in plate contouring and positioning.

Preoperative Mixed-Reality Visualization of Complex Tibial Plateau Fractures and Its Benefit Compared to CT and 3D Printing

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.