Intraoperative 3D imaging in the treatment of elbow fractures--a retrospective analysis of indications, intraoperative revision rates, and implications in 36 cases

An Automatic Method for Elbow Joint Recognition, Segmentation and Reconstruction

Elbow computerized tomography (CT) scans have been widely applied for describing elbow morphology. To enhance the objectivity and efficiency of clinical diagnosis, an automatic method to recognize, segment, and reconstruct elbow joint bones is proposed in this study. The method involves three steps: initially, the humerus, ulna, and radius are automatically recognized based on the anatomical features of the elbow joint, and the prompt boxes are generated. Subsequently, elbow MedSAM is obtained through transfer learning, which accurately segments the CT images by integrating the prompt boxes. After that, hole-filling and object reclassification steps are executed to refine the mask. Finally, three-dimensional (3D) reconstruction is conducted seamlessly using the marching cube algorithm. To validate the reliability and accuracy of the method, the images were compared to the masks labeled by senior surgeons. Quantitative evaluation of segmentation results revealed median intersection over union (IoU) values of 0.963, 0.959, and 0.950 for the humerus, ulna, and radius, respectively. Additionally, the reconstructed surface errors were measured at 1.127, 1.523, and 2.062 mm, respectively. Consequently, the automatic elbow reconstruction method demonstrates promising capabilities in clinical diagnosis, preoperative planning, and intraoperative navigation for elbow joint diseases.

Cone-Beam Computed Tomography (CBCT)-Based Diagnosis of Dental Bone Defects

Cone Beam Computed Tomography (CBCT) has completely changed the way that bone disorders are diagnosed and treated, especially in the dental and maxillofacial domains. This article examines the diverse applications of computed tomography (CBCT) in the diagnosis and treatment of facial trauma, including mandibular, dentoalveolar, and other facial fractures, as well as bone abnormalities like dislocations and fractures. CBCT is useful for a wide range of dental conditions and greatly improves diagnostic accuracy in periodontics, orthodontics, endodontics, and dental implantology. Additionally, a comparison between CBCT and conventional imaging methods was conducted, emphasizing the latter's inferior 3D imaging capabilities, allowing for more precise treatment planning and better patient outcomes with CBCT. Although CBCT has many benefits, it also has some drawbacks, such as requiring specific training for accurate interpretation, cost considerations, and a higher radiation exposure than with traditional dental X-rays. In order to optimize benefits and reduce risks, the conclusion highlights CBCT's revolutionary influence on clinical practice while arguing for its prudent and responsible application.

The Application of Cone Beam Computed Tomography (CBCT) on the Diagnosis and Management of Maxillofacial Trauma

The assessment and management of facial trauma in an acute setting is one of the core services provided by oral and maxillofacial units in the United Kingdom. Imaging is a pre-requisite for appropriate diagnosis and treatment planning, with a combination of plain radiographs and medical-grade CT being the mainstay. However, the emergence of cone beam CT in recent years has led to its wider applications, including facial trauma assessment. It can offer multi-planar reformats and three-dimensional reconstruction at a much lower radiation dose and financial cost than conventional CT. The purpose of this review is to appraise its potential indications in all anatomical areas of maxillofacial trauma and provide our experience at a level 1 trauma centre.

Postoperative computed tomography imaging of pediatric patients with craniosynostosis: radiation dose and image quality comparison between multi-slice computed tomography and O-arm cone-beam computed tomography

BACKGROUND

When postoperative multi-slice computed tomography (MSCT) imaging of patients with craniosynostosis is used, it is usually performed a few days after surgery in a radiology department. This requires additional anesthesia for the patient. Recently, intraoperative mobile cone-beam CT (CBCT) devices have gained popularity for orthopedic and neurosurgical procedures, which allows postoperative CT imaging in the operating room.

OBJECTIVE

This single-center retrospective study compared radiation dose and image quality of postoperative imaging performed using conventional MSCT scanners and O-arm CBCT.

MATERIALS AND METHODS

A total of 104 pediatric syndromic and non-syndromic patients who were operated on because of single- or multiple-suture craniosynostosis were included in this study. The mean volumetric CT dose index (CTDIvol) and dose-length product (DLP) values of optimized craniosynostosis CT examinations (58 MSCT and 46 CBCT) were compared. Two surgeons evaluated the subjective image quality.

RESULTS

CBCT resulted in significantly lower CTDIvol (up to 14%) and DLP (up to 33%) compared to MSCT. Multi-slice CT image quality was considered superior to CBCT scans. However, all scans were considered to be of sufficient quality for diagnosis.

CONCLUSION

The O-arm device allowed for an immediate postoperative CBCT examination in the operating theater using the same anesthesia induction. Radiation exposure was lower in CBCT compared to MSCT scans, thus further encouraging the use of O-arms. Cone-beam CT imaging with an O-arm is a feasible method for postoperative craniosynostosis imaging, yielding less anesthesia to patients, lower health costs and the possibility to immediately evaluate results of the surgical operation.

Implementing 3D fluoroscopy in the management of tibial plateau fractures: Shorter hospitalization and decline in revision surgery, but increase in the duration of surgery and radiation exposure

BACKGROUND

Intraoperative 3D fluoroscopy (3DRX) is increasingly used in fracture management instead of conventional fluoroscopy (RX), but its effect on the treatment and outcome of tibial plateau fractures (TFs) is not well known. This study aims to evaluate whether the use of 3DRX in the treatment of tibial plateau fractures reduces the number of revision surgeries.

METHODS

This retrospective cohort study includes all patients who underwent surgical treatment for TF in a single center from 2014 to 2018. Patient-, fracture-, and treatment characteristics were compared between the 3DRX and RX subgroups. The primary endpoint was the number of patients requiring revision surgery. Secondary endpoints were surgery duration, hospital length of stay, radiation exposure, postoperative complications, and secondary total knee arthroplasty.

RESULTS

Eighty-seven patients were included, of which 36 were treated with 3DRX. Three patients in the RX group required revision surgery, while no revision surgery was performed in the 3DRX group (p = 0.265). The use of 3DRX resulted in significantly more intraoperative adjustments (25% versus 6%; p = 0.024) and an increase in surgery duration (by average of 28 min, p = 0.001), without a significant increase in postoperative wound infections (12% versus 19%; p = 0.374) or fracture-related infections (2% versus 2.8%; p = 0.802). The 3DRX group had an average radiation exposure of 7,985 mGy versus 1,273 mGy in the RX group (p<0.001). The hospital length of stay was 1 day shorter in the 3DRX group (5 days versus 4 days; p = 0.058).

CONCLUSIONS

Implementing 3DRX in treating TFs improves the assessment of fracture alignment and implant position perioperatively, resulting in more intraoperative corrections and no revision surgeries within 6 weeks postoperatively. However, using 3DRX significantly increases perioperative radiation exposure and surgery duration without a significant rise in postoperative infections and a shorter hospital length of stay.

Improved epiphyseal socket placement with intraoperative 3D fluoroscopy: a consecutive series of pediatric all-epiphyseal anterior cruciate ligament reconstruction

PURPOSE

Disturbance of the growth plate during all-epiphyseal anterior cruciate ligament reconstruction (ACLR) socket placement is possible due to the undulation of the distal femoral physis and proximal tibial physis. Therefore, it is important to obtain intraoperative imaging of the guide wire prior to reaming the socket. The purpose of this study was to investigate the effect of the use of 3D intraoperative fluoroscopy on socket placement in patients undergoing all-epiphyseal ACLR. It was hypothesized that 3D imaging would allow for more accurate intraoperative visualization of the growth plate and hence a lower incidence of growth plate violation compared to 2D imaging.

METHODS

Patients under the age of 18 who underwent a primary all-epiphyseal ACL reconstruction by the senior authors and had an available postoperative MRI were retrospectively reviewed. Demographic data, surgical details, and the distances between the femoral socket and distal femoral physis (DFP) and tibial socket and proximal tibial physis (PTP) were recorded. Patients were split into two groups based on type of intraoperative fluoroscopy used: a 2D group and a 3D group. Interrater reliability of radiographic measurements was evaluated using intraclass correlation coefficient (ICC).

RESULTS

Seventy-two patients fit the inclusion criteria and were retrospectively reviewed. 54 patients had 2D imaging and 18 patients had 3D imaging. The mean age at time of surgery was 12.3 ± 1.5 years, 79% of patients were male, and 54% tore their left ACL. The mean time from surgery to postoperative MRI was 2.0 ± 1.1 years. The ICC was 0.92 (95% CI 0.35-0.98), indicating almost perfect interrater reliability. The mean difference in distance between the tibial socket and the PTP was significantly less in the 2D imaging group than the 3D imaging group (1.2 ± 1.7 mm vs 2.5 ± 2.2 mm, p = 0.03). The femoral and tibial sockets touched or extended beyond the DFP or PTP, respectively, significantly less in the 3D group than in the 2D group (11% vs 43%, p < 0.000, 17% vs 65%, p < 0.000).

CONCLUSION

There was a significantly increased distance from the PTP and decreased incidence of DFP violation with use of 3D intraoperative imaging for all-epiphyseal ACLR socket placement. Surgeons should consider utilizing 3D imaging prior to creating femoral and tibial sockets to potentially decrease the risk of physis violation in these patients.

LEVEL OF EVIDENCE

III.

Software-Automated Implant Detection for Intraoperative 3D Imaging-First Clinical Evaluation on 214 Data Sets

Previous studies have demonstrated a frequent occurrence of screw/K-wire malpositioning during surgical fracture treatment under 2D fluoroscopy and a correspondingly high revision rate as a result of using intraoperative 3D imaging. In order to facilitate and accelerate the diagnosis of implant malpositioning in 3D data sets, this study investigates two versions of an implant detection software for mobile 3D C-arms in terms of their detection performance based on comparison with manual evaluation. The 3D data sets of patients who had received surgical fracture treatment at five anatomical regions were extracted from the research database. First, manual evaluation of the data sets was performed, and the number of implanted implants was assessed. For 25 data sets, the time required by four investigators to adjust each implant was monitored. Subsequently, the evaluation was performed using both software versions based on the following detection parameters: true-positive-rate, false-negative-rate, false-detection-rate and positive predictive value. Furthermore, the causes of false positive and false negative detected implants depending on the anatomical region were investigated. Two hundred fourteen data sets with overall 1767 implants were included. The detection parameters were significantly improved (p<.001) from version 1 to version 2 of the implant detection software. Automatic evaluation required an average of 4.1±0.4 s while manual evaluation was completed in 136.15±72.9 s (p<.001), with a statistically significant difference between experienced and inexperienced users (p=.005). In summary, version 2 of the implant detection software achieved significantly better results. The time saved by using the software could contribute to optimizing the intraoperative workflow.

Fluoroscopy of the Elbow: A Cadaveric Study Defining New Standard Projections to Visualize Important Anatomical Landmarks

Background

Despite new 3-dimensional imaging modalities, 2-dimensional fluoroscopy remains the standard intraoperative imaging modality. The elbow has complex anatomy, and defined standard fluoroscopic projections are lacking. Therefore, the aim of this study was to define standard projections of the elbow for intraoperative fluoroscopy.

Methods

This study consisted of 2 parts. In part I, dissected cadaveric elbows were examined under fluoroscopy, and their radiographic anatomical features were assessed, with focus on projections showing defined anatomical landmarks. In part II, projections from part I were verified on entire cadavers to simulate intraoperative imaging. Standard projections for anteroposterior (AP) and lateral views as well as oblique and axial views were recorded.

Results

Eight standardized projections could be defined and included 3 AP, 1 lateral, 2 oblique, and 2 axial views. By applying these specific projections, we could visualize the epicondyles, the trochlea with its medial and lateral borders, the capitellum, the olecranon, the greater sigmoid notch, the coronoid process including its anteromedial facet, the proximal radioulnar joint with the radial tuberosity, and the anterior and posterior joint lines of the distal part of the humerus. These standard projections were reliably obtained using a specific sequence.

Conclusions

Knowledge about radiographic anatomy and standard projections is essential for visualizing important landmarks. With the presented standard projections of the elbow, important anatomical landmarks can be clearly examined. Thus, fluoroscopic visualization of anatomical fracture reduction and correct implant placement should be facilitated.

Clinical Relevance

This basic science cadaveric study defines fluoroscopic standard projections of the elbow essential for visualization of anatomical landmarks during surgery.

Evolution of imaging in surgical fracture management

Intraoperative imaging has been advanced substantially over the last decades. It supports localization of the region of interest, verification of the preoperatively classified fracture pattern, identification of correct insertion point of the implant, placement of instruments and fixation material, and verification of correct fracture reduction and implant positioning. While conventional fluoroscopic 2D imaging remains the gold standard in intraoperative imaging, critical anatomical regions are predestined for intraoperative 3D imaging. Additional options such as perioperative virtual planning, simulation, and surgical training, 3D printing techniques and 3D augmented reality visualization may potentially open new windows to improve surgical results in fracture care. This manuscript presents an update on current and upcoming imaging techniques in orthopaedic and trauma surgery focusing on technical advances for decreasing malreduction, malalignment, and malposition, as well as tips and tricks for daily surgical practice in order to improve clinical outcomes and patients' and surgeons' safety.

Diagnostic accuracy of intraoperative CT-imaging in complex articular fractures - a cadaveric study

Anatomic reconstruction of articular fractures is one of the critical factors in later achieving good functional outcome. Intraoperative 3D imaging has been shown to offer better evaluation and therefore can significantly improve the results. The purpose of this study was to assess the difference between intraoperative three-dimensional fluoroscopy (3D) and intraoperative computed tomography (iCT) imaging regarding fracture reduction, implant placement and articular impressions in a distal humeral fracture model. AO type 13-B2 fracture pattern were created in upper extremity cadaver specimens. Articular step-offs, intra-articular screw placement and intraarticular impressions of different degrees of severity were created. All specimens had imaging performed. For each articular pattern 3D fluoroscopy in standard (3Ds) and high quality (3Dh) were performed (Arcadis Orbic, Siemens, Germany) as well as an intraoperative CT scan (iCT, Airo, Brainlab, Germany). Three observers evaluated all imaging studies regarding subjective and objective parameters. iCT is more precise than 3D fluoroscopic imaging for detection of articular impressions. Articular step-offs and intraarticular screw placement are similar for iCT and 3D. Subjective imaging quality is the highest for iCT and lowest for 3Ds. Intraoperative CT may be particularly useful in assessing articular impressions and providing a good subjective image quality for the surgeon.

Posterior pelvic ring fractures: Intraoperative 3D-CT guided navigation for accurate positioning of sacro-iliac screws

INTRODUCTION

Posterior pelvic ring fractures frequently pose a problem of stability with an elevated risk of complications. The traditional method of percutaneous sacroiliac (SI) stabilization with the use of fluoroscopic image amplifiers demands a high degree of experience and has an elevated risk of screws' malpositioning.

HYPOTHESIS

Intraoperative 3D-CT scan coupled with a navigation system (O-Arm^©) can allow screw fixation accuracy while limiting the risk of complications for the treatment of posterior pelvic ring fractures.

MATERIAL AND METHODS

Patients with posterior pelvic ring fractures stabilized with percutaneous SI screws through O-Arm^© navigation from August 2008 to December 2017 were analyzed. A modified Gras classification was used to determine screws' positioning under CT visualization, and intraoperative and early postoperative complications were documented.

RESULTS

Among the 21 patients evaluated, 14 men and 7 women with a mean age of 57.8 years (range 25-91), receiving 39 screws, the rate of misplacement was low: 82% grade I, 15.4% grade II, and only 2.6% grade III. Only one patient underwent revision surgery, not because of misplacement but rather for a secondary implant loosening. No complications occurred in this series.

DISCUSSION

This study documented a large series of patients treated for pelvic ring fractures using the intraoperative 3D-CT O-Arm^© guided navigation. This surgical approach provided a precise and safe SI screw positioning with no complications.

LEVEL OF EVIDENCE

IV, Retrospective study.

Comparison of intraoperative 2D vs. 3D imaging in open reduction and fixation of distal radius fractures

PURPOSE

In the volar plating of distal radius fractures, intraoperative three-dimensional (3D) imaging is designed to allow better judgment regarding screw and implant positioning compared with conventional intraoperative two-dimensional (2D) imaging. We evaluated the impact of these two imaging modalities on the rates of intraoperative revision and secondary surgery, as well as the need for implant removal during follow-up.

METHODS

A retrospective analysis of consecutive patients who underwent volar plate osteosynthesis for isolated distal radius fractures between January 2008 and April 2016 was performed. Patient files were evaluated for intraoperative imaging findings, intraoperative and postoperative revision rates, and implant removal during follow-up. Additional analyses of radiation exposure, operation time, and hospitalization time were performed.

RESULTS

A total of 314 patients were analyzed (mean age: 54 ± 19 years; 210 females). For 246 patients, only 2D imaging was performed, while the remaining 68 patients underwent both 2D and 3D imaging (O-Arm, Medtronic). The intraoperative revision rate was significantly (p < 0.001) higher with 3D imaging (32.4%) compared with 2D imaging (2.0%). The postoperative revision rates were similar between both the groups (2.9% vs. 2.0%; p = 0.674). Compared with 2D imaging, the use of the Medtronic O-Arm resulted in a significantly lower implant removal rate (8.8% vs. 18.7%; p = 0.036) during follow-up.

CONCLUSION

Compared with conventional 2D imaging, the use of intraoperative 3D imaging significantly increased the intraoperative revision rate and has the potential for positive long-term effects for lowering the risk of requiring an implant removal.

A review of existing and potential computer user interfaces for modern radiology

Abstract

The digitalization of modern imaging has led radiologists to become very familiar with computers and their user interfaces (UI). New options for display and command offer expanded possibilities, but the mouse and keyboard remain the most commonly utilized, for usability reasons. In this work, we review and discuss different UI and their possible application in radiology. We consider two-dimensional and three-dimensional imaging displays in the context of interventional radiology, and discuss interest in touchscreens, kinetic sensors, eye detection, and augmented or virtual reality. We show that UI design specifically for radiologists is key for future use and adoption of such new interfaces. Next-generation UI must fulfil professional needs, while considering contextual constraints.

Teaching Points

• The mouse and keyboard remain the most utilized user interfaces for radiologists.

• Touchscreen, holographic, kinetic sensors and eye tracking offer new possibilities for interaction.

• 3D and 2D imaging require specific user interfaces.

• Holographic display and augmented reality provide a third dimension to volume imaging.

• Good usability is essential for adoption of new user interfaces by radiologists.

Intraoperative assessment of reduction and implant placement in acetabular fractures-limitations of 3D-imaging compared to computed tomography

Background

In acetabular fractures, the assessment of reduction and implant placement has limitations in conventional 2D intraoperative imaging. 3D imaging offers the opportunity to acquire CT-like images and thus to improve the results. However, clinical experience shows that even 3D imaging has limitations, especially regarding artifacts when implants are placed. The purpose of this study was to assess the difference between intraoperative 3D imaging and postoperative CT regarding reduction and implant placement.

Methods

Twenty consecutive cases of acetabular fractures were selected with a complete set of intraoperative 3D imaging and postoperative CT data. The largest detectable step and the largest detectable gap were measured in all three standard planes. These values were compared between the 3D data sets and CT data sets. Additionally, possible correlations between the possible confounders age and BMI and the difference between 3D and CT values were tested.

Results

The mean difference of largest visible step between the 3D imaging and CT scan was 2.0 ± 1.8 mm (0.0–5.8, p = 0.02) in the axial, 1.3 ± 1.4 mm (0.0–3.7, p = 0.15) in the sagittal and 1.9 ± 2.4 mm (0.0–7.4, p = 0.22) in the coronal views. The mean difference of largest visible gap between the 3D imaging and CT scan was 3.1 ± 3.6 mm (0.0–14.1, p = 0.03) in the axial, 4.6 ± 2.7 mm (1.2–8.7, p = 0.001) in the sagittal and 3.5 ± 4.0 mm (0.0–15.4, p = 0.06) in the coronal views. A positive correlation between the age and the difference in gap measurements in the sagittal view was shown (rho = 0.556, p = 0.011).

Conclusions

Intraoperative 3D imaging is a valuable adjunct in assessing reduction and implant placement in acetabular fractures but has limitations due to artifacts caused by implant material. This can lead to missed malreduction and impairment of clinical outcome, so postoperative CT should be considered in these cases.

Elbow Posterolateral Dislocation Accompanying Flexor Group Origo Rupture without Fracture - A Case Report

INTRODUCTION

We wished to present a case that had elbow posterolateral dislocation accompanying complete medial collateral ligament rupture(MCLR) and complete flexor group origo rupture (FGOR) without fracture.

CASE REPORT

A30-year-old man came to emergency department after falling on the outstretched palm. After first physical examination and radiologic searches, elbow joint posterolateral dislocation was diagnosed. Together with sedoanalgesia, elbow dislocation was reduced, and instability evaluation by applying varus and valgus stress tests was performed. Positive valgus stress test and palpation sign which indicated soft tissue damage on the medial side of elbow were determined. Control roentgenograms showed no osseous pathology. By magnetic resonance imaging, elbow dislocation diagnosis accompanying MCLR and FGOR without fracture was confirmed. Using medial approach, ruptured MCL and elbow FGO repairing procedures were performed.

CONCLUSION

The complications of elbow dislocation without fracture, which is barely seen, should be treated through appropriate treatment strategies after meticulous physical examination and radiologic evaluation. Hence, possible sequelae could be prevented or satisfactory results could be obtained.