3D printing in hand surgery

Bone Graft Substitutes-What Are My Options?

We examine the range of available bone graft substitutes often used in nonunion and malunion surgery of the upper extremity. Synthetic materials such as calcium sulfate, beta-calcium phosphate ceramics, hydroxyapatite, bioactive glass, and 3D printed materials are discussed. We delve into the advantages, disadvantages, and clinical applications for each, considering factors such as biocompatibility, osteoconductivity, mechanical strength, and resorption rates. This review provides upper extremity surgeons with insights into the available array of bone graft substitutes. We hope that the reviews helps in the decision-making process to achieve optimal outcomes when treating nonunion and malunion of the upper extremity.

Clinical Applications of Three-Dimensional Printing in Upper Extremity Surgery: A Systematic Review

Three-dimensional printing for medical applications in surgery of the upper extremity has gained in popularity as reflected by the increasing number of publications. This systematic review aims to provide an overview of the clinical use of 3D printing in upper extremity surgery.

METHODS

We searched the databases PubMed and Web of Science for clinical studies that described clinical application of 3D printing for upper extremity surgery including trauma and malformations. We evaluated study characteristics, clinical entity, type of clinical application, concerned anatomical structures, reported outcomes, and evidence level.

RESULTS

We finally included 51 publications with a total of 355 patients, of which 12 were clinical studies (evidence level II/III) and 39 case series (evidence level IV/V). The types of clinical applications were for intraoperative templates (33% of a total of 51 studies), body implants (29%), preoperative planning (27%), prostheses (15%), and orthoses (1%). Over two third of studies were linked to trauma-related injuries (67%).

CONCLUSION

The clinical application of 3D printing in upper extremity surgery offers great potential for personalized approaches to aid in individualized perioperative management, improvement of function, and ultimately help to benefit certain aspects in the quality of life.

A Review of the Use of 3D Printing Technology in Treatment of Scaphoid Fractures

Background: Three-dimensional (3D) printing technology is increasingly commercially viable for pre-surgical planning, intraoperative templating, jig creation and customised implant manufacture. The challenging nature of scaphoid fracture and nonunion surgery make it an obvious target. The aim of this review is to determine the use of 3D printed technologies in the treatment of scaphoid fractures. Methods: This is a review of the Medline, Embase and Cochrane Library databases examining studies aimed at therapeutic use of 3D printing, also known as rapid prototyping or additive technology, in the treatment of scaphoid fractures. All studies published up to and including November 2020 were included in the search. Relevant data extracted included modality of use (as template/model/guide/prosthesis), operative time, accuracy of reduction, radiation exposure, follow-up duration, time to union, complications and study quality. Results: A total of 649 articles were identified, of which 12 met the full inclusion criteria. Analysis of the articles showed that 3D printing techniques can be utilised in myriad ways to aid planning and delivery of scaphoid surgery. Percutaneous guides for Kirschner-wire (K-wire) fixation of non-displaced fractures can be created; custom guides can be printed to aid reduction of displaced or non-united fractures; patient-specific total prostheses may recreate near-normal carpal biomechanics and a simple model may help graft harvesting and positioning. Conclusions: This review found that the use of 3D printed patient-specific models and templates in scaphoid surgery can improve accuracy and speed, and reduce radiation exposure. 3D printed prostheses may also restore near-normal carpal biomechanics without burning bridges for potential future procedures. Level of Evidence: Level III (Therapeutic).

3D planning and patient-specific surgical guides in forearm osteotomy in children: Radiographic accuracy and clinical morbidity

INTRODUCTION

Three-dimensional (3D) planning and patient-specific surgical guides are increasingly used in the treatment of skeletal deformities. The present study hypothesis was that they are reliable in forearm osteotomy in children, with low morbidity.

MATERIAL AND METHODS

Twenty-there children with one or several osteotomies to correct forearm deformities were retrospectively included: 9 (20 osteotomies) with surgical guide (G+), and 14 (28 osteotomies) without (G-). Etiologies comprised 8 cases of Madelung disease (3G+, 5G-) and 15 of post-traumatic malunion (6G+, 9G-). Mean age at surgery was 14.8±1.9 years. The patient-specific 3D-printed polyamide guides were produced from 3D virtual models based on 3D CT reconstruction. Mean follow-up was 22.1±13.6 months.

RESULTS

Mean correction error was 5.3°±4.1 and 4.2°±4.1 in the frontal and sagittal planes respectively in G+ (p=0.6). Surgery time was significantly shorter in G+, by a mean 42min (p=0.02). Mean total radiation dose (preoperative CT+intraoperative fluoroscopy) was significantly higher in G+ (p<0.0001). Complications rates were similar between groups. Improvement in PRWE score was significantly greater in G+.

CONCLUSION

The present preliminary results were encouraging. 3D planning and patient-specific surgical guides can be used in the treatment of forearm deformity in children.

LEVEL OF EVIDENCE

III; retrospective cohort study.

In-hospital production of 3D-printed casts for non-displaced wrist and hand fractures

Objectives: To examine the clinical feasibility and results of a multidisciplinary workflow, employing rapid three-dimensional (3D) scanning and modeling software along with a high-speed printer, for in-hospital production of patient-specific 3D-printed casts, for the treatment of non-displaced wrist and hand fractures. Methods: Consenting adult patients admitted to the emergency department (ED) due to wrist or hand fractures between January and February 2021 were prospectively enrolled. The study participants underwent conversion of the standard plaster of Paris cast to a 3D-printed cast one week after the ED visit, and follow-up examinations were performed around two, six, and twelve weeks later. The primary objective was to examine the clinical feasibility in terms of complexity and length of the overall procedure. Secondary outcomes were patient-reported impressions and radiological results. Results: Twenty patients (16 males, mean age 37 ± 13.1 years) were included. The entire printing workflow took a mean of 161 ± 8 min. All patients demonstrated clinical improvement and fracture union at final follow-up, with no pressure sores or loss of reduction. Patient-reported comfort and satisfaction rates were excellent. The mean Visual Analog Scale was 0.9 ± 1.1 and 0.6 ± 1, and the mean Disabilities of the Arm, Shoulder, and Hand score was 18.7 ± 9.5 and 7.6 ± 7.6 at 2 and 6 weeks after application of the 3D-printed cast, respectively. Conclusion: The in-hospital workflow was feasible and efficient, with excellent clinical and radiographic results and high patient satisfaction and comfort rates. Our medical center now routinely provides this cast option for non-displaced wrist and hand fractures.

Level of evidence: IV, Therapeutic Study

Clinical applications and prospects of 3D printing guide templates in orthopaedics

Background

With increasing requirements for medical effects, and huge differences among individuals, traditional surgical instruments are difficult to meet the patients' growing medical demands. 3D printing is increasingly mature, which connects to medical services critically as well. The patient specific surgical guide plate provides the condition for precision medicine in orthopaedics.

Methods

In this paper, a systematic review of the orthopedic guide template is presented, where the history of 3D-printing-guided technology, the process of guides, and basic clinical applications of orthopedic guide templates are described. Finally, the limitations of the template and possible future directions are discussed.

Results

The technology of 3D printing surgical templates is increasingly mature, standard, and intelligent. With the help of guide templates, the surgeon can easily determine the direction and depth of the screw path, and choose the angle and range of osteotomy, increasing the precision, safety, and reliability of the procedure in various types of surgeries. It simplifies the difficult surgical steps and accelerates the growth of young and mid-career physicians. But some problems such as cost, materials, and equipment limit its development.

Conclusions

In different fields of orthopedics, the use of guide templates can significantly improve surgical accuracy, shorten the surgical time, and reduce intraoperative bleeding and radiation. With the development of 3D printing, the guide template will be standardized and simplified from design to production and use. 3D printing guides will be further sublimated in the application of orthopedics and better serve the patients.

The translational potential of this paper

Precision, intelligence, and individuation are the future development direction of orthopedics. It is more and more popular as the price of printers falls and materials are developed. In addition, the technology of meta-universe, digital twin, and artificial intelligence have made revolutionary effects on template guides. We aim to summarize recent developments and applications of 3D printing guide templates for engineers and surgeons to develop more accurate and efficient templates.

Overview of In-Hospital 3D Printing and Practical Applications in Hand Surgery

Three-dimensional (3D) printing is spreading in hand surgery. There is an increasing number of practical applications like the training of junior hand surgeons, patient education, preoperative planning, and 3D printing of customized casts, customized surgical guides, implants, and prostheses. Some high-quality studies highlight the value for surgeons, but there is still a lack of high-level evidence for improved clinical endpoints and hence actual impact on the patient's outcome. This article provides an overview over the latest applications of 3D printing in hand surgery and practical experience of implementing them into daily clinical routine.

3D-Printed Microfluidics and Potential Biomedical Applications

3D printing is a smart additive manufacturing technique that allows the engineering of biomedical devices that are usually difficult to design using conventional methodologies such as machining or molding. Nowadays, 3D-printed microfluidics has gained enormous attention due to their various advantages including fast production, cost-effectiveness, and accurate designing of a range of products even geometrically complex devices. In this review, we focused on the recent significant findings in the field of 3D-printed microfluidic devices for biomedical applications. 3D printers are used as fabrication tools for a broad variety of systems for a range of applications like diagnostic microfluidic chips to detect different analytes, for example, glucose, lactate, and glutamate and the biomarkers related to different clinically relevant diseases, for example, malaria, prostate cancer, and breast cancer. 3D printers can print various materials (inorganic and polymers) with varying density, strength, and chemical properties that provide users with a broad variety of strategic options. In this article, we have discussed potential 3D printing techniques for the fabrication of microfluidic devices that are suitable for biomedical applications. Emerging diagnostic technologies using 3D printing as a method for integrating living cells or biomaterials into 3D printing are also reviewed.

A Standardized Hand Fracture Fixation Training Framework using Novel 3D Printed Ex Vivo Hand Models: Our Experience as a Unit

Surgery for hand trauma accounts for a significant proportion of the plastic surgery training curriculum. The aim of this study was to create a standardized simulation training module for hand fracture fixation with Kirschner wire (K-wire) techniques for residents to create a standardized hand training framework that universally hones their skill and prepares them for their first encounter in a clinical setting.

Methods

A step-ladder approach training with 6 levels of difficulty on 3-dimensional (3D) printed ex vivo hand biomimetics was employed on a cohort of 20 plastic surgery residents (n = 20). Assessment of skills using a score system (global rating scale) was performed in the beginning and at the end of the module by hand experts of our unit.

Results

The overall average scores of the cohort before and after assessment were 23.75/40 (59.4%) and 34.7/40 (86.8%), respectively. Significant (P < 0.01) difference of improvement of skills was noted on all trainees. All trainees confirmed that the simulated models provided in this module were akin to the patient scenario and noted that it helped them improve their skills with regard to K-wire fixation techniques, including improvement of their understanding of the 3D bone topography.

Conclusions

We demonstrate a standardized simulation training framework that employs 3D printed ex vivo hand biomimetics proved to improve the skills of residents and that paves the way to more universal, standardized and validated training across hand surgery. This is, to our knowledge, the first standardized method of simulated training on such hand surgical cases.

In-hospital professional production of patient-specific 3D-printed devices for hand and wrist rehabilitation

The reported use of 3D printing in hand and wrist rehabilitation has been mostly limited to feasibility studies and case series so far. Some of the reasons are the lack of purpose-built scanning applications, complicated digital design software, and lengthy and error-prone printing processes. We propose a multidisciplinary workflow for in-hospital mass production of patient-specific 3D-printed devices for hand and wrist rehabilitation.