A Comparison of Radiographic Outcomes between 3D Preoperative Planning and Conventional Planning in the Osteosynthesis of Distal Radius Fractures

Insights and trends review: the role of three-dimensional technology in upper extremity surgery

The use of three-dimensional (3-D) technology in upper extremity surgery has the potential to revolutionize the way that hand and upper limb procedures are planned and performed. 3-D technology can assist in the diagnosis and treatment of conditions, allowing virtual preoperative planning and surgical templating. 3-D printing can allow the production of patient-specific jigs, instruments and implants, allowing surgeons to plan and perform complex procedures with greater precision and accuracy. Previously, cost has been a barrier to the use of 3-D technology, which is now falling rapidly. This review article will discuss the current status of 3-D technology and printing, including its applications, ethics and challenges in hand and upper limb surgery. We have provided case examples to outline how clinicians can incorporate 3-D technology in their clinical practice for congenital deformities, management of acute fracture and malunion and arthroplasty.

Outcomes of the Management of Distal Radius Fractures in the Last 5 Years: A Meta-analysis of Randomized Controlled Trials

Objective  Over the last decades, volar locking plates (VLPs) have been the mainstay treatment for distal radius fractures (DRFs). With the growing body of evidence, we systematically reviewed studies on recent VLP modifications. Methods  A systematic search was performed in the PubMed/MEDLINE database for studies published in English in the past five years. The inclusion criteria were randomized controlled trials (RCTs) on the operative treatment of DRFs. We excluded ongoing trials and studies not directly addressing DRF. The primary outcomes assessed were subjective (such as the scores on the Disabilities of the Arm, Shoulder and Hand [DASH] questionnaire, the Patient-rated Wrist Evaluation [PRWE], the European Quality of Life-5 Dimensions [EQ-5D], the 36-item Short Form Health Survey [SF-36], and the Visual Analog Scale [VAS]) and objective clinical outcomes (the complication rate). Results  We identified 29 articles published from 2016 to 2020 with high quality of evidence, except for one, which had evidence of moderate quality. In total, 3,079 DRFs were analyzed in the present study. All studies except one had a greater proportion of female participants, and only in 1 study the mean age of the sample was < 40 years old. There were no significant differences between the VLP and external fixation (EF) in terms of the scores on the DASH ( p  = 0.18) and PRWE ( p  = 0.77). The VLP alone without pronator quadratus (PQ) repair yielded significantly better outcomes. Conclusion  In unstable fractures, the VLP and EF yielded comparable long-term results. There is no clear benefit of adding PQ repair to current the VLP surgical technique. Level of Evidence  Level I.

Computer-assisted preoperative planning of bone fracture fixation surgery: A state-of-the-art review

Background: Bone fracture fixation surgery is one of the most commonly performed surgical procedures in the orthopedic field. However, fracture healing complications occur frequently, and the choice of the most optimal surgical approach often remains challenging. In the last years, computational tools have been developed with the aim to assist preoperative planning procedures of bone fracture fixation surgery.

Objectives: The aims of this review are 1) to provide a comprehensive overview of the state-of-the-art in computer-assisted preoperative planning of bone fracture fixation surgery, 2) to assess the clinical feasibility of the existing virtual planning approaches, and 3) to assess their clinical efficacy in terms of clinical outcomes as compared to conventional planning methods.

Methods: A literature search was performed in the MEDLINE-PubMed, Ovid-EMBASE, Ovid-EMCARE, Web of Science, and Cochrane libraries to identify articles reporting on the clinical use of computer-assisted preoperative planning of bone fracture fixation.

Results: 79 articles were included to provide an overview of the state-of-the art in virtual planning. While patient-specific geometrical model construction, virtual bone fracture reduction, and virtual fixation planning are routinely applied in virtual planning, biomechanical analysis is rarely included in the planning framework. 21 of the included studies were used to assess the feasibility and efficacy of computer-assisted planning methods. The reported total mean planning duration ranged from 22 to 258 min in different studies. Computer-assisted planning resulted in reduced operation time (Standardized Mean Difference (SMD): -2.19; 95% Confidence Interval (CI): -2.87, -1.50), less blood loss (SMD: -1.99; 95% CI: -2.75, -1.24), decreased frequency of fluoroscopy (SMD: -2.18; 95% CI: -2.74, -1.61), shortened fracture healing times (SMD: -0.51; 95% CI: -0.97, -0.05) and less postoperative complications (Risk Ratio (RR): 0.64, 95% CI: 0.46, 0.90). No significant differences were found in hospitalization duration. Some studies reported improvements in reduction quality and functional outcomes but these results were not pooled for meta-analysis, since the reported outcome measures were too heterogeneous.

Conclusion: Current computer-assisted planning approaches are feasible to be used in clinical practice and have been shown to improve clinical outcomes. Including biomechanical analysis into the framework has the potential to further improve clinical outcome.

An Experimental Study of a 3D Bone Position Estimation System Based on Fluoroscopic Images

To compare a 3D preoperative planning image and fluoroscopic image, a 3D bone position estimation system that displays 3D images in response to changes in the position of fluoroscopic images was developed. The objective of the present study was to evaluate the accuracy of the estimated position of 3D bone images with reference to fluoroscopic images. Bone positions were estimated from reference points on a fluoroscopic image compared with those on a 3D image. The four reference markers positional relationships on the fluoroscopic image were compared with those on the 3D image to evaluate whether a 3D image may be drawn by tracking positional changes in the radius model. Intra-class correlations coefficients for reference marker distances between the fluoroscopic image and 3D image were 0.98–0.99. Average differences between measured values on the fluoroscopic image and 3D bone image for each marker corresponding to the direction of the bone model were 1.1 ± 0.7 mm, 2.4 ± 1.8 mm, 1.4 ± 0.8 mm, and 2.0 ± 1.6 mm in the anterior-posterior view, ulnar side lateral view, posterior-anterior view, and radial side lateral view, respectively. Marker positions were more accurate in the anterior-posterior and posterior-anterior views than in the radial and ulnar side lateral views. This system helps in real-time comparison of dynamic changes in preoperative 3D and intraoperative fluoroscopy images.

Usefulness of Preoperative Planning by Three-Dimensional Planning Software for Pedicle Screw Placement in Thoracolumbar Surgeries: <i>Misplacement Rate and Associated Risk Factors</i>

Introduction

A number of imaging technologies have been developed to reduce the risk of pedicle screw (PS) misplacement. For example, preoperative three-dimensional (3D) planning can reportedly enhance implant placement accuracy in some orthopedic surgeries. However, no study has investigated the effect of preoperative 3D planning on PS placement without intraoperative 3D navigation. Thus, in this study, we aim to examine the accuracy of PS placement and identify the risk factors for PS misplacement in thoracolumbar surgeries performed using preoperative 3D planning software with intraoperative fluoroscopic guidance in a retrospective study.

Methods

In total, 25 consecutive patients (197 PSs) underwent thoracic or lumbar spinal fusion surgeries using preoperative 3D planning with intraoperative fluoroscopic guidance. PS misplacement was graded based on the degree of perforation (Grade 0, no perforation; Grade 1, <2 mm; Grade 2, 2-4 mm; Grade 3, >4 mm) observed in postoperative computed tomography (CT). Deviations between planned and actual PSs were evaluated by matching preoperative and postoperative CT volume images for each vertebra.

Results

The overall PS misplacement rate was 6.6% (Grade 1: 4.0%, Grade 2: 1.5%, Grade 3: 1.0%). The median linear deviations of PS entry points between planned and actual locations were determined to be 3.3 mm and 3.3 mm for the horizontal and vertical axes, respectively. The median angular deviations of the PS axis were 6.2° and 4.5° for the transverse and sagittal planes, respectively. Multivariate analysis revealed that horizontal deviation of the PS entry point was the sole factor associated with Grade ≥1 PS misplacement (odds ratio=2.47, p<0.001).

Conclusions

Preoperative 3D planning software without intraoperative 3D navigation was able to achieve a relatively low PS misplacement ratio among the reported ratio of conventional techniques without navigation. Surgeons should carefully ensure that the entry point is consistent with preoperative planning, especially in the mediolateral direction to avoid misplacement in this method.

Preoperative Predictions of Distal Screw Length for the Osteosynthesis of Distal Radius Fractures

Background: The objective of this study was to clarify whether anteroposterior dimension of the radius along the screw axis of a fixed angle volar locking plate (VLP) can be predicted from the width of the radius on the VLP. Methods: Sixty-nine wrists in 68 patients with distal radius fractures that underwent fixation with a fixed angle VLPs were evaluated. All patients underwent pre- and postoperative computed tomographic scans of the distal radius. The transverse width of the radius was measured at the position of the third screw hole from the proximal edge. The anteroposterior dimension of the radius (R) was measured along the axes of the distal screws. The distal row screw holes were defined as R1, R2, R3, and R4 from the radial to the ulnar side. Correlation analysis between the width and the anteroposterior dimension, and single regression analysis were performed for each screw hole. The correlations amongst the R values for the different distal row screws were also assessed. Results: The correlation coefficients between the transverse width and anteroposterior dimensions were 0.54, 0.58, 0.55, and 0.42 for R1, R2, R3, and R4 respectively (p < 0.05). The regression equations were R1 = 0.49W + 7.99, R2 = 0.47W + 11.8, R3 = 0.52W + 10.8, and R4 = 0.41W + 11.5 respectively. The correlation coefficients among anteroposterior dimensions were 0.85, 0.64, 0.59, 0.70, 0.61, and 0.80 for R1/R2, R1/R3, R1/R4, R2/R3, R2/R4, and R3/R4 respectively (p < 0.01). Conclusions: There were significant correlations in the anteroposterior dimensions amongst the distal row screw lengths. The regression equations used in this study may be helpful to predict the length of distal row screw and prevent complications due to inappropriate screw choices. Level of Evidence: Level III (Therapeutic).

Dose reduction potential in cone-beam CT imaging of upper extremity joints with a twin robotic x-ray system

Cone-beam computed tomography is a powerful tool for 3D imaging of the appendicular skeleton, facilitating detailed visualization of bone microarchitecture. This study evaluated various combinations of acquisition and reconstruction parameters for the cone-beam CT mode of a twin robotic x-ray system in cadaveric wrist and elbow scans, aiming to define the best possible trade-off between image quality and radiation dose. Images were acquired with different combinations of tube voltage and tube current-time product, resulting in five scan protocols with varying volume CT dose indices: full-dose (FD; 17.4 mGy), low-dose (LD; 4.5 mGy), ultra-low-dose (ULD; 1.15 mGy), modulated low-dose (mLD; 0.6 mGy) and modulated ultra-low-dose (mULD; 0.29 mGy). Each set of projection data was reconstructed with three convolution kernels (very sharp [Ur77], sharp [Br69], intermediate [Br62]). Five radiologists subjectively assessed the image quality of cortical bone, cancellous bone and soft tissue using seven-point scales. Irrespective of the reconstruction kernel, overall image quality of every FD, LD and ULD scan was deemed suitable for diagnostic use in contrast to mLD (very sharp/sharp/intermediate: 60/55/70%) and mULD (0/3/5%). Superior depiction of cortical and cancellous bone was achieved in FD_Ur77 and LD_Ur77 examinations (p < 0.001) with LD_Ur77 scans also providing favorable bone visualization compared to FD_Br69 and FD_Br62 (p < 0.001). Fleiss' kappa was 0.618 (0.594-0.641; p < 0.001), indicating substantial interrater reliability. In this study, we demonstrate that considerable dose reduction can be realized while maintaining diagnostic image quality in upper extremity joint scans with the cone-beam CT mode of a twin robotic x-ray system. Application of sharper convolution kernels for image reconstruction facilitates superior display of bone microarchitecture.

Utility of an image fusion system for 3D preoperative planning and fluoroscopy in the osteosynthesis of distal radius fractures

Background

Recently, computerized virtual surgery planning has been increasingly applied in various orthopedic procedures. In this study, we developed an image fusion system for 3D preoperative planning and fluoroscopy for the osteosynthesis. To assess the utility of image fusion system, we evaluated the reproducibility of preoperative planning in the osteosynthesis of distal radius fractures with using the image fusion system, and compared with the reproducibility of the patients without using the image fusion system.

Methods

Forty-two wrists of 42 distal radius fracture patients who underwent osteosynthesis using volar locking plates were evaluated. The patients were divided into two groups. Image fusion group utilized three-dimensional (3D) preoperative planning and image fusion system. Control group utilized only 3D preoperative planning. In both groups, 3D preoperative planning was performed in order to determine reduction, placement, and choice of implants. In the image fusion group, the outline of planned image was displayed on a monitor overlapping with fluoroscopy images during surgery. Reductions were evaluated by volar tilt and radial inclination of 3D images. Plate positions were evaluated with distance to joint surface, plate center axis position, and inclination relative to the radius axis. Screw choices were recorded for the plan and actual choices for each screw hole. Differences in the parameters between pre- and postoperative images were evaluated. Differences in reduction shape, plate positions, and screw choices were compared between groups.

Results

The differences in the distance from plate to joint surface were significantly smaller in the image fusion group compared to the control group (P < 0.01). The differences in the distal screw choices were significantly smaller in the image fusion group compared to the control group (P < 0.01).

Conclusions

The image fusion system was useful to reproduce the planned plate position and distal screw choices in the osteosynthesis of distal radius fractures.

Trial registration

ClinicalTrials.gov, NCT03764501