Entwicklung der 3‑D-Bildgebung in der Versorgung orthopädischer Verletzungen

[Innovative 3D imaging]

Intraoperative 2D fluoroscopy is often performed for repositioning and implant control. However, this does not always provide the details needed to reliably detect joint steps or incorrect repositioning. Over the last few years, intraoperative 3D imaging has been established and further developed. Multiple studies demonstrate an advantage and better intraoperative control through 3D imaging. Examples are the upper ankle, the proximal tibia and the distal radius; the rates of intraoperative revisions with digital volume tomography (DVT) are between 20-30%. Technical advancements, such as metal artifact reductions, automated plane setting, automated screw detection, and robotic DVT devices, facilitate intraoperative operation, shorten surgical time, and provide improved image quality. By processing the data sets in the form of an immersive, computer-simulated image in terms of "augmented reality" (AR), increased precision can be achieved intraoperatively while reducing radiation exposure. The implementation of these systems is associated with costs, which are offset by cost savings from avoided revisions. Adequate counter-financing is still lacking at the present time. Intraoperative 3D imaging represents an important tool for intraoperative control. The current data situation makes it necessary to address the routine use of 3D procedures, especially in the joint area. The indications are becoming increasingly broader. Technical innovations such as robotics and AR have significantly improved 3D devices in recent years and offer high potential for integration into the OR.

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.

Design, delivery, and evaluation of seminars and hands-on courses worldwide on intraoperative imaging in orthopedic trauma

INTRODUCTION

Although intraoperative imaging is important for assessing the quality of several steps during fracture fixation, most trainees and surgeons have received little formal education on this topic and report they learn "on the job" and "through practice". A planning committee of orthopedic trauma surgeons was established to design a curriculum using "backward planning" to identify patient problems, identify gaps in surgeons' knowledge and skills, and define competencies as a framework for education in order to optimize patient care.

MATERIALS AND METHODS

The committee defined 8 competencies related to intraoperative imaging, with detailed learning objectives for each one (e.g. select the imaging modality, set up the operating room). An interactive, case-based half-day seminar to deliver these objectives for 2-D and 3-D intraoperative imaging during the fixation of common fractures was designed. The seminar was delivered in several locations worldwide over a 6-year period and evaluation and assessment data were gathered online. A full-day procedures course was added and delivered 6 times to address the skills component of competencies.

RESULTS

17 seminars and 6 courses were delivered and attended by an average of 26 and 17 participants respectively (ranges 13-42 and 13-20). Pre-event gap analysis and assessment question scores confirmed needs and motivation to learn in all events. 97% of the 442 seminar participants and 98% of the 100 course participants would recommend the events to colleagues. An average of 88% and 90% respectively learned something new and plan to use it in their practice (range 63%-100%). Commitment to change (CTC) statements showed intended practice improvements related to all competencies.

DISCUSSION

The large percentages of high impact ratings for all events suggest the content met the needs of many participants. Post-event reduction in gap scores and an increase in the desired level of ability for most competencies suggests the content addressed many gaps.

CONCLUSIONS

Case-based, interactive seminars and courses addressing knowledge, skills, and attitudes to optimize the use of intraoperative imaging during the fixation of common fractures help address unmet educational needs for trainees and complements existing formal training.

[Hybrid operating room : Application in trauma surgery and orthopaedics]

BACKGROUND

For some years now, more and more hospitals in Germany have acquired so-called hybrid operating rooms. In these operating rooms it is possible to produce three-dimensional imaging during the operation. Originally developed for cardiovascular surgery, these rooms are increasingly being used for interdisciplinary purposes. Previous experiences in the use for trauma surgery and orthopedics has shown that three-dimensional imaging can have a positive effect on the success of surgery.

OBJECTIVE

Can minimally invasive operations on the spine benefit intraoperatively from three-dimensional imaging with respect to operating times and results?

METHODS

Minimally invasive operations on the spine performed at the UKSH Campus Kiel between 2015 and 2018 in the hybrid operating room were considered. These were compared to minimally invasive spinal surgery performed in conventional operating rooms.

RESULTS

As is usual with the establishment of a new procedure, there are initially longer operating times. With regular use and appropriate training and experience of the personnel, the processes can be optimized.

CONCLUSION

Due to the accuracy of the three-dimensional imaging, errors can be detected and eliminated at an early stage during the operation. Revisions are less frequent. In contrast, there is increased radiation exposure and sometimes longer operation and anesthesia times.

New advances in intra-operative imaging in trauma

The invention of flat-panel detectors led to a revolution in medical imaging. The major benefits of this technology are a higher image quality and dose reduction. Flat-panel detectors have proved to be superior to standard C-arms (= C-arm with radiograph source and image intensifier).

Cone-beam computed tomography (cone-beam CT) is a 3D data set, which can be acquired with a flat-panel detector. The cone-shaped beam is used for 3D data generation. For cone-beam CT acquisition, the flat-panel detector rotates around the patient lying on the operating table. Intra-operative cone-beam CT can be a very helpful tool in orthopaedic surgery. Immediate control of fracture reduction and implant positioning in high image quality can reduce the need for secondary revision surgery due to implant malposition.

In recent years there has been a revival of standard fan beam CT technology in operating rooms. Fixed and mobile systems are available. Fixed systems are typically placed on a sliding gantry. Different mobile intra-operative CT scanners were recently introduced. Due to their mobility, they are not bound to a specific operating room. The use of standard intra-operative CT scanners results in high 3D image quality but, in comparison with a cone-beam CT scanner, fluoroscopy is not possible.

The introduction of flat-panel detectors has led to improvements in intra-operative image quality combined with dose reduction. The possibility of high-quality 3D imaging in combination with navigation can assure optimal implant placement. Due to immediate control of the osteosynthesis, revision surgery at a later time can be prevented.

Cite this article: EFORT Open Rev 2018;3 DOI: 10.1302/2058-5241.3.170055

Utility of Third-Week Postoperative Radiographs in the Management of Ankle Fractures

OBJECTIVES

To evaluate the costs and efficacy of radiographs taken in the third week after fixation of bimalleolar and trimalleolar fractures.

PATIENTS AND METHOD

A retrospective evaluation was made of patients who underwent surgical fixation because of bimalleolar and trimalleolar fractures between January 1, 2008, and October 1, 2013. Patient demographics (age, gender, body mass index), fracture type, follow-up periods, and fixation methods were recorded, and the radiographs taken on postoperative day 1, at 3 weeks, 6 weeks, and the final follow-up were examined by 2 orthopedists. Measurements were taken of the medial clear space (MCS ≤ 4 mm), the tibiofibular clear space (TFCS < 5 mm), and the talocrural angle (TCA = 83° ± 4°) on the mortise radiograph and of the overlap between the tibial tubercle and fibula (TFO > 10 mm) on the anteroposterior radiograph; residual step (mm) was measured on the lateral radiograph.

RESULTS

A total of 263 patients were examined, and of these, 112 were included for evaluation. In the measurements of postoperative day 1, third week, and sixth week and the final radiographs, no statistically significant difference was determined in the MCS, TFCS, TCA, TFO, and residual step values. Because the cost of a series of 3-way ankle radiographs in Turkey is US$3.81 per patient, the cost of the control series for the 112 patients in this study was US$ 427.3.

CONCLUSIONS

In patients treated surgically for bimalleolar and trimalleolar fractures, the radiographs taken in the third week rarely resulted in a change of patient management. Therefore, it simply constitutes an additional cost for the patient or the hospital.

LEVELS OF EVIDENCE

Level III: Retrospective Cohort study.