3D printing in orthopaedic surgery: a scoping review of randomized controlled trials

Short-term results of minimally invasive surgery using a 3D-printed guide for the treatment of hallux valgus

INTRODUCTION

Minimally invasive surgery (MIS) is often used to treat hallux valgus deformities, as it is associated with few wound complications and shorter recovery times. Minimally invasive chevron osteotomy and Akin osteotomy (MICA) is a common minimally invasive treatment for HV. However, effective correction of hallux valgus and precise screw placement during MIS are difficult. The aim of this study was to introduce and evaluate the clinical and radiographic effectiveness of a novel MIS technique involving the use of a 3D-printed guide for hallux valgus.

MATERIALS AND METHODS

We retrospectively studied the results of MIS with a 3D-printed guide plate for symptomatic hallux valgus from May 2022 to December 2023. The preoperative and postoperative hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), first metatarsal pronation angle (M1PA), tibial sesamoid position (TSP), forefoot width, visual analogue scale (VAS) score, AOFAS Hallux MTP-IP score, and the number of intraoperative fluoroscopy were measured.

RESULTS

A total of 22 feet in 19 patients were included in the study. There were 15 women and 4 men with an average age of 38.0 y (range 16-61). The preoperative HVA, IMA, DMAA and M1PA were 30.3 ± 10.7°, 13.9 ± 2.8°, 8.3 ± 2.9° and 16.3 ± 6.5°, respectively. The postoperative HVA, IMA, DMAA and M1PA were 10.7 ± 4.1°, 5.7 ± 1.8°, 2.3 ± 1.7° and 3.5 ± 2.1°, respectively. The forefoot width decreased from 92.1 ± 5.5 mm to 85.6 ± 5.4 mm on average. The VAS and TSP ranged from 4.4 ± 0.9 and 4.9 ± 0.8 to 0.3 ± 0.6 and 2.0 ± 1.1, respectively. The AOFAS Hallux MTP-IP scores improved from 59.1 ± 10.7 to 94.8 ± 5.7 on average. The average number of fluoroscopy shots during operation were 34 times (range 30 to 38).

CONCLUSIONS

A 3D printed guide technique can be beneficial for precise positioning of the first metatarsal head, enhancing the accuracy of screw placement, and reducing radiation exposure.

Clinical added value of 3D printed patient-specific guides in orthopedic surgery (excluding knee arthroplasty): a systematic review

INTRODUCTION

Patient-specific guides (PSGs) provide customized solutions and enhanced precision. However, the question remains: does clinical evidence support the added value of PSGs? This study critically appraises, summarizes, and compares the literature to assess the clinical value of PSGs in orthopedic surgery.

MATERIALS AND METHODS

PubMed and Embase were used to search for studies reporting on randomized controlled trials (RCTs) that compared the use of PSGs with a control group for an orthopedic intervention, excluding knee arthroplasty. The risk of bias was assessed using the Cochrane risk-of-bias tool (RoB 2). The clinical value was expressed as patient reported outcome measures (PROMs), complications, accuracy, surgery duration, blood loss, and radiation exposure. Relative and absolute differences were determined, and whether these were negative or positive for using PSGs.

RESULTS

From 6310 studies, 27 RCTs were included, covering various interventions. The studies' heterogeneity prevented meta-analysis. Six (22.2%) of the included articles scored low risk of bias. Significant differences in the benefit of PSGs were reported across all included metrics: 32.2% in PROMs, 22.7% in complications, 69.8% in accuracy, 42.1% in surgery duration, 46.7% in blood loss, and 93.3% in radiation exposure. No significant negative differences were found in any of the studies.

CONCLUSION

PSGs generally show superior outcomes for accuracy and radiation exposure across multiple intervention types, while the reduction in complications was primarily significant in spinal fusion surgery. For PROMs, complications in other treatments, surgery duration, and blood loss, there may be clinical added value but future well-designed RCTs are needed to provide stronger evidence.

Three-dimensional printed anatomical models as an educational tool for orthopaedic surgical trainees - A single institution experience

Objective

To evaluate the utility of three-dimensional (3D) anatomical models as an educational tool among Orthopaedic surgical trainees.

Methods

Seven types of 3D anatomical models - humerus, elbow, ankle, calcaneum, knee, femur, and pelvis- based on patients' computational tomography (CT) scans were printed in the study institution and used by surgical trainees preoperatively. Responses were collected in the form of a Likert scale questionnaire. Descriptive statistics of participants' ratings were calculated. Non-parametric analysis using Wilcoxon test and Kruskal-Wallis test was performed to determine if effectiveness varied with gender, clinical experience, and anatomical model type.

Design

Observational cross-sectional study.

Setting

Single center study.

Participant selection criteria

All participants within a period of 16 months who were Orthopaedic surgical trainees within the study institution and utilised 3D anatomical models preoperatively were selected for this study.

Outcome measures and comparisons

Primary outcome was Likert scale ratings for three aspects - understanding of patients' anatomy, learning of a patient-specific orthopaedic condition, retention of anatomical knowledge.

Results

This study revealed that 3D anatomical models were well-received as an educational tool among Orthopaedic surgical trainees. There were no significant differences between gender, clinical experience or anatomical model type regarding 3D models in improving understanding of patient anatomy and retention of anatomical knowledge (p < 0.05). There were significant differences among participants based on clinical experience regarding the use of 3D models in learning of the patient-specific orthopaedic condition (p = 0.0106).

Conclusions

Preliminary results from this study demonstrate overall effectiveness of 3D models as an educational tool in Orthopaedic surgery, but is limited by the qualitative nature of data collected. Higher quality evidence is required to demonstrate that 3D anatomical models are effective tools to impart critical knowledge of anatomy to surgical trainees.

Level of evidence

IV.

Patient-Specific 3-Dimensional-Printed Orthopedic Implants and Surgical Devices Are Potential Alternatives to Conventional Technology But Require Additional Characterization

Background

Three-dimensional (3D) printing allows anatomical models, guides, and implants to be easily customized to individual patients. Three-dimensional-printed devices can be used for a number of purposes in the medical field, yet there is a lack of data on the implementation of 3D-printed patient-specific implants and surgical guides in orthopedics. The objective of this review of the literature was to summarize the implementation of 3D printing in orthopedic surgery and identify areas that require more investigation.

Methods

PubMed and Scopus were used to perform a literature search. Articles that described 3D-printed patient-specific orthopedic implants or intraoperative guides were reviewed. Relevant articles were compiled and summarized to determine the role of personalized 3D-printed implants in orthopedic surgery.

Results

A total of 58 papers were selected. Overall, 3D-printed implants and surgical guides were shown to be effective in the selected cases. Patients with bone tumors benefitted from custom 3D-printed implants, which allow aggressive resection while preserving the function and mechanical stability of the limb. Eighty-one percent of devices were made using titanium, and 48% of articles reported the use of 3D printing in oncology. Some reported adverse events including wound dehiscence, periprosthetic infection, dislocation, and sequelae of malignancy. Regulations surrounding the use of 3D-printed surgical devices are ambiguous.

Conclusions

Three-dimensional-printed orthopedic implants and guides present an alternative to commercial devices, as they allow for customizability that is useful in cases of anatomic complexity. A variety of materials were surveyed across multiple subspecialties. Large controlled studies are necessary to compare patient-specific implants with the standard of care and evaluate their safety profiles over time.

Case Report: Custom made 3D implants for glenoid tumor reconstruction should be designed as reverse total shoulder arthroplasty

Background and objectives

Isolated bone tumors of the glenoid are exceedingly rare occurrence and pose a substantial surgical challenge. 3D printing technology has been proved to be a reliable tool to reconstruct complex anatomical part of the skeleton. We initially used this technology to reconstruct the glenoid component of the shoulder in a hemiarthroplasty configuration. We subsequently changed to a reverse shoulder arthroplasty.

Methods

Two patients were reconstructed with a hemiarthroplasty and 2 with a reverse configuration. Patients files were reviewed for radiographic analysis, pain and function scores.

Results

Mean follow-up was 36.44 ± 16.27 months. All patients are alive and disease free. The two patients who benefitted from a hemiarthroplasty demonstrated a rapid deterioration of the proximal humeral articular surface. Given their pain and function scores, they subsequently required revision towards a total shoulder arthroplasty. Following this conversion, one patient presented a shoulder dislocation requiring surgical reintervention. We did not observe any loosening or infection in this short series.

Conclusions

Custom made glenoid reconstruction should be designed as a reverse shoulder arthroplasty given the mechanical constrains on the proximal humerus and the extent of the surgery invariably damaging the suprascapular neurovascular bundle.

Osteochondroma-like parosteal osteosarcoma: A case highlighting diagnostic challenge and surgical advances

Parosteal osteosarcomas are uncommon malignant bone tumors that arise from the bone surface. Their heterogenous components can present challenges in diagnosis. We present a case of a rare variant of this tumor known as an osteochondroma-like parosteal osteosarcoma, which was initially misdiagnosed as a cartilaginous tumor on core needle biopsy. Surgical resection of the tumor ultimately allowed for definitive diagnosis. Our case demonstrates the limitations of needle biopsy in diagnosing variants of parosteal osteosarcoma and the vital role of multidisciplinary discussions in guiding diagnosis and treatment. Furthermore, our case utilizes 3-dimensional printing technology in the surgical treatment, and illustrates the recent advances in patient-specific surgical techniques.

Automatic identification of radius and ulna bone landmarks on 3D virtual models

BACKGROUND

For bone morphology and biomechanics analysis, landmarks are essential to define position, orientation, and shape. These landmarks define bone and joint coordinate systems and are widely used in these research fields. Currently, no method is known for automatically identifying landmarks on virtual 3D bone models of the radius and ulna. This paper proposes a knowledge-based method for locating landmarks and calculating a coordinate system for the radius, ulna, and combined forearm bones, which is essential for measuring forearm function. This method does not rely on pre-labeled data.

VALIDATION

The algorithm is validated by comparing the landmarks placed by the algorithm with the mean position of landmarks placed by a group of experts on cadaveric specimens regarding distance and orientation.

RESULTS

The median Euclidean distance differences between all the automated and reference landmarks range from 0.4 to 1.8 millimeters. The median angular differences of the coordinate system of the radius and ulna range from -1.4 to 0.6 degrees. The forearm coordinate system's median errors range from -0.2 to 2.0 degrees. The median error in calculating the rotational position of the radius relative to the ulna is 1.8 degrees.

CONCLUSION

The automatic method's applicability depends on the use context and desired accuracy. However, the current method is a validated first step in the automatic analysis of the three-dimensional forearm anatomy.

A comparison between 3D printed models and standard 2D planning in the use of metal block augments in revision knee arthroplasty

OBJECTIVES

The study focused on the ability to predict the need and size of femoral and tibial augmentation using standard two-dimensional (2D) templates and models created with three-dimensional (3D) printing in surgical planning.

PATIENTS AND METHODS

This observational cohort study included 28 consecutive patients (22 females, 6 males; mean age: 71±7.3 years; range, 54 to 82 years) with periprosthetic joint infection recruited between March 2021 and September 2023 undergoing revision total knee arthroplasty revision (TKA). Standard planning was made using calibrated X-ray images. The 3D planning started with computed tomography scans to generate a 3D template of the distal femur and proximal tibia. The model was exported to a 3D printer to produce a patient-specific phantom. The surgery was then simulated on the 3D phantom using revision knee arthroplasty instrumentation to evaluate the appropriate augmentation to use until a correct alignment was obtained.

RESULTS

Three-dimensional planning predicted the need for femoral and tibial augments in 22 (78.6%) cases at both the tibial and femoral components, while 2D planning correctly predicted the need for augmentation in 17 (60.7%) for the tibial side and 18 (64.3%) for the femoral side. The Cohen's kappa demonstrated a significant agreement between the 3D planning for the femoral metal block and the intraoperative requirement (kappa=0.553), whereas 2D planning showed only nonsignificant poor agreement (kappa=0.083). In contrast, the agreement between 2D or 3D preoperative planning for tibial augment and the intraoperative requirement was nonsignificant (kappa=0.130 and kappa=0.158, respectively). On the femoral side, 2D planning showed only a fair nonsignificant correlation (r=0.35, p=0.069), whereas 3D planning exhibited substantial agreement with the actual thickness of the implanted augment (r=0.65, p<0.001). On the tibial side, 3D and 2D planning showed substantial agreement with the actual size of implanted augments (3D planning, r=0.73, p<0.001; 2D planning, r=0.69, p<0.001).

CONCLUSION

Prediction based on 3D computed tomography segmentation showed significant agreement with the intraoperative need for augmentations in revision TKA. The results suggest that planning with 3D printed models represents a stronger aid in this kind of surgery rather than standard 2D planning, providing greater accuracy in the prediction of the required augmentation in revision TKA.

Three-dimensional-printing-guided preoperative planning of upper and lower extremity pediatric orthopedic surgeries: A systematic review of surgical outcomes

Purpose

Three-dimensional printing has evolved into a cost-effective and accessible tool. In orthopedic surgery, creating patient-specific anatomical models and instrumentation improves visualization and surgical accuracy. In pediatric orthopedics, three-dimensional printing reduces operating time, radiation exposure, and blood loss by enhancing surgical efficacy. This review compares outcomes of three-dimensional printing-assisted surgeries with conventional surgeries for upper and lower extremity pediatric surgeries.

Methods

A complete search of medical literature up to August 2023, using Ovid Medline, EMBASE, Scopus, Web of Science, and Cochrane Library was conducted in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Broad search terms included "pediatrics," "orthopedic," and "3D-printing." Eligible studies were assessed for intraoperative time, blood loss, and fluoroscopy exposure.

Results

Out of 3299 initially identified articles, 14 articles met inclusion criteria. These studies included 409 pediatric patients, with ages averaging 9.51 years. The majority were retrospective studies (nine), with four prospective and one experimental study. Studies primarily utilized three-dimensional printing for navigation templates and implants. Results showed significant reductions in operative time, blood loss, and radiation exposure with three-dimensional printing. Complication occurrences were generally lower in three-dimensional printing surgeries, but there was no statistical significance.

Conclusions

Three-dimensional printing is an emerging technology in the field of orthopedics, and it is primarily used for preoperative planning. For pediatric upper and lower extremity surgeries, three-dimensional printing leads to decreased operating room time, decreased intraoperative blood loss, and reduced radiation exposure. Other uses for three-dimensional printing include education, patient communication, the creation of patient-specific instrumentation and implants.

Level of evidence

Level III.

The Future of Total Elbow Arthroplasty: A Statistical Forecast Model for Germany

This study provides a statistical forecast for the development of total elbow arthroplasties (TEAs) in Germany until 2045. The authors used an autoregressive integrated moving average (ARIMA), Error-Trend-Seasonality (ETS), and Poisson model to forecast trends in total elbow arthroplasty based on demographic information and official procedure statistics. They predict a significant increase in total elbow joint replacements, with a higher prevalence among women than men. Comprehensive national data provided by the Federal Statistical Office of Germany (Statistisches Bundesamt) were used to quantify TEA's total number and incidence rates. Poisson regression, exponential smoothing with Error-Trend-Seasonality, and autoregressive integrated moving average models (ARIMA) were used to predict developments in the total number of surgeries until 2045. Overall, the number of TEAs is projected to increase continuously from 2021 to 2045. This will result in a total number of 982 (TEAs) in 2045 of mostly elderly patients above 80 years. Notably, female patients will receive TEAs 7.5 times more often than men. This is likely influenced by demographic and societal factors such as an ageing population, changes in healthcare access and utilization, and advancements in medical technology. Our projection emphasises the necessity for continuous improvements in surgical training, implant development, and rehabilitation protocols.

Clinical Workflow Algorithm for Preoperative Planning, Reduction and Stabilization of Complex Acetabular Fractures with the Support of Three-Dimensional Technologies

Background: Treatment of pelvic injuries poses serious problems for surgeons due to the difficulties of the associated injuries. The objective of this research is to create a clinical workflow that integrates three-dimensional technologies in preoperative planning and performing surgery for the reduction and stabilization of associated acetabular fractures. Methods: The research methodology consisted of integrating the stages of virtual preoperative planning, physical preoperative planning, and performing the surgical intervention in a newly developed clinical workflow. The proposed model was validated in practice in a pilot surgical intervention. Results: On a complex pelvic injury case of a patient with an associated both-column acetabular fracture (AO/OTA-62C1g), we presented the results obtained in the six stages of the clinical workflow: acquisition of three-dimensional (3D) images, creation of the virtual model of the pelvis, creation of the physical model of the pelvis, preoperative physical simulation, orthopedic surgery, and imaging validation of the intervention. The life-size 3D model was fabricated based on computed tomography imagistics. To create the virtual model, the images were imported into Invesalius (version 3.1.1, CTI, Brazil), after which they were processed with MeshLab (version 2023.12, ISTI-CNR, Italy) and FreeCAD (version 0.21.2, LGPL, FSF, Boston, MA, USA). The physical model was printed in 21 h and 37 min using Ultimaker Cura software (version 5.7.2), on an Ultimaker 2+ printing machine through a Fused Deposition Modeling process. Using the physical model, osteosynthesis plate dimensions and fixation screw trajectories were tested to reduce the risk of neurovascular injury, after which they were adjusted and resterilized, which enhanced preoperative decision-making. Conclusions: The life-size physical model improved anatomical appreciation and preoperative planning, enabling accurate surgical simulation. The tools created demonstrated remarkable accuracy and cost-effectiveness that support the advancement and efficiency of clinical practice.

Minimally invasive hallux valgus surgery using 3D printed patient specific instrumentation

In this technical report study, we describe technique for performing the osteotomy and screw passage in minimally invasive fourth-generation hallux valgus surgery with transverse and akin extra-articular metaphyseal osteotomy (META) using a 3D-printed patient-specific surgical instrumentation guide. In an effort to minimize the learning curve and address the variability associated with technical corrections and screw placement, we have initiated the creation of personalized patient-specific instrumentation guides using 3D printing. Our hypothesis is that this approach will enhance safety, precision, decrease surgical time, and reduce exposure to radiation. Level of Evidence: Level V, expert opinion.

Health-related quality of life in patients with extremity bone sarcoma after surgical treatment: a systematic review

PURPOSE

We conducted a systematic review of studies reporting on measurement of health-related quality of life (HRQoL), with a special focus on the use of the preference-weighted instruments, in patients with extremity bone sarcoma treated with limb-salvage surgery or amputation.

METHODS

We searched MedLine, Embase, Cochrane Library and Web of Science for English-language studies reporting on HRQoL of patients with bone sarcoma from inception to 28 August 2023. All records found were independently reviewed by two reviewers. We used the Newcastle-Ottawa Scale (NOS) and the CONSORT 2010 checklist to assess the quality of the cohort and randomised studies, respectively.

RESULTS

The search identified 1225 records, of which 16 studies were included for data extraction. Only one study used a preference-weighted instrument for measuring HRQoL in a small sample of patients (n = 28). Ten studies used the generic SF-36 questionnaire, but no preference-weighted HRQoL based on SF-6D was derived from the SF-36 scores. Most studies comparing HRQoL between amputation and limb-salvage surgery reported no significant differences. Twelve cohort studies scored six or more out of nine points based on the NOS. The only randomised study scored 54% on the CONSORT 2010 checklist.

CONCLUSIONS

The approaches used to measure HRQoL were inconsistent and outcome scores varied substantially. Only one study used preference-weighted instruments for HRQoL measurement. Future research into the surgical treatment of extremity bone sarcoma should consider the use of preference-weighted instruments to measure HRQoL, which will therefore enable economic evaluation for the growing orthopaedic armamentarium of novel surgical interventions.

REGISTRATION

This systematic review was registered with the PROSPERO International prospective register of systematic reviews (CRD42021282380).

Setting up a biomodeling, virtual planning, and three-dimensional printing service in Uruguay

Virtual surgical planning and three-dimensional (D) printing are rapidly becoming essential for challenging and complex surgeries around the world. An Ibero-American survey reported a lack of awareness of technology benefits and scarce financial resources as the two main barriers to widespread adoption of 3-D technologies. The Pereira Rossell Hospital Center is a publicly funded maternal and pediatric academic clinical center in Uruguay, a low-resource Latin American country, that successfully created and has been running a 3-D unit for 4 years. The present work is a step-by-step review of the 3-D technology implementation process in a hospital with minimal financial investment. References to training, software, hardware, and the management of human resources are included. Difficulties throughout the process and future challenges are also discussed.

Systematic review of the utility and limits of 3D printing in spine surgery

OBJECTIVE

The main objective of this study has been to demonstrate why additive printing allows to make complex surgical pathological processes that affect the spine more visible and understandable, increasing precision, safety and reliability of the surgical procedure.

METHODS

A systematic review of the articles published in the last 10 years on 3D printing-assisted spinal surgery was carried out, in accordance with PRISMA 2020 declaration. Keywords "3D printing" and "spine surgery" were searched in Pubmed, Embase, Cochrane Database of Systematic Reviews, Google Scholar and Opengrey databases, which was completed with a manual search through the list of bibliographic references of the articles that were selected following the defined inclusion and exclusion criteria.

RESULTS

From the analysis of the 38 selected studies, it results that 3D printing is useful in surgical planning, medical teaching, doctor-patient relationship, design of navigation templates and spinal implants, and research, optimizing the surgical process by focusing on the patient, offering magnificent support during the surgical procedure.

CONCLUSIONS

The use of three-dimensional printing biomodels allows: making complex surgical pathological processes that affect the spine more visible and understandable; increase the accuracy, precision and safety of the surgical procedure, and open up the possibility of implementing personalized treatments, mainly in tumor surgery.

Advanced Preoperative Planning Techniques in the Management of Complex Proximal Humerus Fractures

This review evaluates the current literature on the recent advances of preoperative planning in the management of complex proximal humerus fractures (PHF). PHFs can pose a considerable challenge for orthopaedic surgeons due to their diversity in presentation and complexity. Poor preoperative planning can lead to prolonged operations, increased blood loss, higher risk of complications, and increased stress on the surgical team. Recent advances have seen the evolution of preoperative planning from conventional methods to computer-assisted virtual surgical technology (CAVST) and three-dimensional (3D) printing, which have been highlighted as transformative tools for improving preoperative planning and postoperative outcomes. CAVST allows the creation of 3D renderings of patient-specific anatomy, clearly demonstrating fracture patterns and facilitating detailed planning for arthroplasty or surgical fixation. The early studies show promising outcomes however the literature calls for more high-quality randomised controlled trials. Using 3D printing for high-fidelity simulation involving patient-specific physical models offers an immersive experience for surgical planning. Preoperative planning with 3D printing reduces operative time, blood loss and use of fluoroscopy. The technology's potential to produce customisable surgical implants further improves its versatility. There is a need for a cost analysis for the use of these technologies within the orthopaedic field, particularly considering the high expense of 3D printing materials and extended hospital stays until the printed models are available. CAVST and 3D printing also show promising applications within high-fidelity simulation surgical training, with CAVST offering possibilities in virtual reality and haptic-enhanced simulations and 3D printing providing physical models for trainee surgeons to hone their skills. Moving forward, a reduction in the cost of 3D printing and the advancement of CAVST using artificial intelligence would lead to future improvement. In conclusion, preoperative planning supported by these innovative technologies will play a pivotal role in improving surgical outcomes and training for complex PHF cases.

The Era of Digital Orthopedics: A Bone or Bane?

Orthopedics, the medical specialty dedicated to diagnosing, treating, and preventing disorders of the musculoskeletal system, has long been a cornerstone of healthcare. With an aging population and an increasing emphasis on maintaining an active lifestyle, the demand for orthopedic care is on the rise. However, the field of orthopedics is rapidly evolving, and one of the most significant developments in recent years is the emergence of digital orthopedics [1, 2]. This transformation is reshaping the way orthopedic care is delivered, from diagnosis and treatment to patient outcomes and beyond. In this editorial, we explore the concept of digital orthopedics, its implications, and the potential benefits it offers to both patients and health-care professionals.

The Use of Patient-Specific Implants for the Treatment of Upper Extremity Fractures

In this article, we discuss the use of three-dimensional (3-D) printed patient-specific implants in the management of upper extremity fractures. Traditional fracture fixation methods involve the use of standard-sized implants, which may not adequately address the needs of every patient, particularly those who have complications related to fracture nonunion or malunion and those who have significant bone loss. The benefits and limitations of this technology are also discussed, along with considerations for implementation in clinical practice. Overall, the use of 3-D printed patient-specific implants holds promise for improving the accuracy and efficacy of upper extremity fracture management.

3D Printed Orthopaedic External Fixation Devices: A Systematic Review

BACKGROUND

External fixators are complex, expensive orthopaedic devices used to stabilize high-energy and complex fractures of the extremities. Although the technology has advanced dramatically over the last several decades, the mechanical goals for fracture stabilization of these devices have remained unchanged. Three-dimensional (3D) printing technology has the potential to advance the practice and access to external fixation devices in orthopaedics. This publication aims to systematically review and synthesize the current literature on 3D printed external fixation devices for managing orthopaedic trauma fractures.

METHODS

The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocols were followed for this manuscript with minor exceptions. PubMed, Embase, Cochrane Review, Google Scholar, and Scopus online databases were systematically searched. Two independent reviewers screened the search results based on predetermined inclusion and exclusion criteria related to 3D printing and external fixation of fractures.

RESULTS

Nine studies met the inclusion criteria. These included one mechanical testing study, two computational simulation studies, three feasibility studies, and three clinical case studies. Fixator designs and materials varied significantly between authors. Mechanical testing revealed similar strength to traditional metal external fixators. Across all clinical studies, five patients underwent definitive treatment with 3D printed external fixators. They all had satisfactory reduction and healing with no reported complications.

CONCLUSIONS

The current literature on this topic is heterogeneous, with highly variable external fixator designs and testing techniques. A small and limited number of studies in the scientific literature have analyzed the use of 3D printing in this area of orthopaedic surgery. 3D printed external fixation design advancements have yielded promising results in several small clinical case studies. However, additional studies on a larger scale with standardized testing and reporting techniques are needed.

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.

3D printing in fracture treatment : Current practice and best practice consensus

The use of 3D printing in orthopedic trauma is supported by clinical evidence. Existing computed tomography (CT) data are exploited for better stereotactic identification of morphological features of the fracture and enhanced surgical planning. Due to complex logistic, technical and resource constraints, deployment of 3D printing is not straightforward from the hospital management perspective. As a result not all trauma surgeons are able to confidently integrate 3D printing into the daily practice. We carried out an expert panel survey on six trauma units which utilized 3D printing routinely. The most frequent indications are acetabular and articular fractures and malalignments. Infrastructure and manpower structure varied between units. The installation of industrial grade machines and dedicated software as well as the use of trained personnel can enhance the capacity and reliability of fracture treatment. Setting up interdisciplinary jointly used 3d printing departments with sound financial and management structures may improve sustainability. The sometimes substantial logistic and technical barriers which impede the rapid delivery of 3D printed models are discussed.

Virtual Scoliosis Surgery Using a 3D-Printed Model Based on Biplanar Radiographs

The aim of this paper is to describe a protocol that simulates the spinal surgery undergone by adolescents with idiopathic scoliosis (AIS) by using a 3D-printed spine model. Patients with AIS underwent pre- and postoperative bi-planar low-dose X-rays from which a numerical 3D model of their spine was generated. The preoperative numerical spine model was subsequently 3D printed to virtually reproduce the spine surgery. Special consideration was given to the printing materials for the 3D-printed elements in order to reflect the radiopaque and mechanical properties of typical bones most accurately. Two patients with AIS were recruited and operated. During the virtual surgery, both pre- and postoperative images of the 3D-printed spine model were acquired. The proposed 3D-printing workflow used to create a realistic 3D-printed spine suitable for virtual surgery appears to be feasible and reliable. This method could be used for virtual-reality scoliosis surgery training incorporating 3D-printed models, and to test surgical instruments and implants.

Elbow hemiarthroplasty with a 3D-printed megaprosthesis for defects of the distal humerus or proximal ulna after tumour resection : a preliminary report

AIMS

The aim of this study was to investigate the feasibility of application of a 3D-printed megaprosthesis with hemiarthroplasty design for defects of the distal humerus or proximal ulna following tumour resection.

METHODS

From June 2018 to January 2020, 13 patients with aggressive or malignant tumours involving the distal humerus (n = 8) or proximal ulna (n = 5) were treated by en bloc resection and reconstruction with a 3D-printed megaprosthesis with hemiarthroplasty, designed in our centre. In this paper, we summarize the baseline and operative data, oncological outcome, complication profiles, and functional status of these patients.

RESULTS

Preparation of the prosthesis was a mean of 8.0 days (SD 1.5), during which time no patients experienced tumour progression. The mean operating time and intraoperative blood loss were 158.1 minutes (SD 67.6) and 176.9 ml (SD 187.8), respectively. All of the prostheses were implanted successfully. During a mean follow-up of 25.7 months (SD 7.8), no patients died, but four had complications (two superficial wound problems, one temporary palsy of radial nerve, and one dislocation). No aseptic loosening, structural failure, infection, heterotopic ossification, or degenerative arthritis was seen in this study. The mean flexion of the elbow was 119.6° (SD 15.9°) and the mean extension lag was 11.9° (SD 13.8°). The mean Musculoskeletal Tumor Society 93 score and Mayo Elbow Performance Score were 28.4 (SD 0.9) and 97.7 (SD 4.4), respectively.

CONCLUSION

The custom-made, 3D-printed megaprosthesis with hemiarthroplasty is a feasible option for functional reconstruction after resection of a tumour in the distal humerus or proximal ulna. Cite this article: Bone Joint J 2022;104-B(6):747-757.