The effect of three-dimensional (3D) printing on quantitative and qualitative outcomes in paediatric orthopaedic osteotomies: a systematic review

In Situ Fixation and Intertrochanteric Osteotomy for Severe Slipped Capital Femoral Epiphysis Following Femoral Neck Fracture: A Case Report with Application of Virtual Surgical Planning and 3D-Printed Patient-Specific Instruments

Background: Femoral neck fractures are rare but serious injuries in children and adolescents, often resulting from high-energy trauma and prone to complications like avascular necrosis (AVN) and nonunion. Even rarer is the development of slipped capital femoral epiphysis (SCFE) following femoral neck fracture, which presents unique diagnostic and treatment challenges. SCFE can destabilize the femoral head, with severe cases requiring complex surgical interventions. Case presentation: This report details a case of a 15-year-old male with autism spectrum disorder (ASD) who developed severe SCFE one month after treatment for a Delbet type III femoral neck fracture. The condition was managed with an Imhäuser intertrochanteric osteotomy (ITO), in situ fixation (ISF), and osteochondroplasty (OChP), supported by virtual surgical planning (VSP) and 3D-printed patient-specific instruments (PSIs) for precise correction and fixation. Discussion: The surgery was completed without complications. Six months after the operation, the patient exhibited a pain-free, mobile hip with radiographic evidence of fracture healing and no signs of AVN. Functional outcomes were favorable despite rehabilitation challenges due to ASD. Conclusions: The Imhäuser ITO, combined with ISF and OChP, effectively addressed severe SCFE after femoral neck fracture, minimizing AVN risk. VSP and PSIs enhanced surgical accuracy and efficiency, demonstrating their value in treating rare and complex pediatric orthopedic conditions.

The Use of 3-Dimensional Modeling and Printing in Corrective Osteotomies of the Malunited Pediatric Forearm: A Systematic Review and Meta-Analysis

INTRODUCTION

Forearm fractures contribute up to 40% of all pediatric fractures, with ≤39% of conservatively managed fractures resulting in malunion. Surgical management of malunion is challenging as precise calculation of multiplanar correction is required to obtain optimal outcomes. Advances in 3D computer modeling and printing have shown promising results in orthopaedics, reducing surgical time, blood loss, and fluoroscopy. This systematic review and meta-analysis are the first to explore the accuracy and functional outcome of 3D techniques in pediatric diaphyseal forearm malunion correction.

METHODS

A systematic review was carried out according to PRISMA guidelines.

RESULTS

Sixteen studies (44 patients) were included. Average 2D residual deformity was 1.84° (SD=1.68°). The average gain in range of movement (ROM) was 76.08° (SD=41.75°), with a statistically significant difference between osteotomies ≤12 months from injury and >12 months (96.36° vs. 64.91°, P = 0.027). Below a 2D residual deformity of 5.28°, no statistically significant difference on gain of ROM was found, indicating this as a nonconsequential residual deformity (P = 0.778). Multivariate regression analysis showed that 2D residual deformity and time to osteotomy only account for 6.3% gain in ROM, indicating that there are more factors to be researched.

CONCLUSION

This study found superior accuracy of 3D techniques, reporting lower residual deformities than published standard osteotomy data; however, the volume of literature was limited. Larger studies are required to explore additional factors that influence accuracy and ROM, such as 3D residual deformity and the effect of particular 3D printed adjuncts. This will aid clarity in determining superiority and improve cost-effectiveness.

Derotational Corrective Osteotomy for Pediatric Forearm Malunion: A Case Report

In this case report, we describe an eight-year-old boy with both-bone forearm diaphyseal fracture that was treated conservatively after closed reduction with manipulation. Nine months after the injury, he returned to consultation, presenting a rotational deformity of the forearm and 20° of pronosupination limitation. He was submitted to corrective osteotomies, using three-dimensional (3D) planning and templating, using a double approach, and fixation with a four screw holes plate in each osteotomy. At one year of follow-up, there are signs of bone consolidation and complete recovery of range of motion.

Methods for three-dimensional characterization of the acetabulum prior to pelvic reorientation osteotomy: a scoping review

Periacetabular osteotomy is the gold standard treatment for acetabular dysplasia. The great variability of acetabular dysplasia requires a personalized preoperative planning improved by 3D reconstruction and computer-assisted surgery. To plan the displacement of the acetabular fragment by a pelvic osteotomy, it is necessary to define a reference plane and a method to characterize 3D acetabular orientation. A scoping review was performed on PubMed to search for articles with a method to characterize the acetabulum of native hips in a 3D reference frame. Ninety-eight articles out of 3815 reports were included. Three reproducible reference planes were identified: the anterior pelvic plane, the Standardization and Terminology Committee plane used in gait analysis, and the sacral base plane. The different methods for 3D analysis of the acetabulum were divided in four groups: global orientation, triplanar measurements, segmentation, and surface coverage of the femoral head. Two methods were found appropriate for reorientation osteotomies: the global orientation by a vector method and the triplanar method. The global orientation method relies on the creation of a vector from the acetabular rim, from the acetabular surface or from successive planes. Normalization of the global acetabular vector would correct acetabular dysplasia by a single alignment maneuver on an ideal vector. The triplanar method, based on angle measurements at the center of the femoral head, would involve correction of anomalies by considering axial, frontal, and sagittal planes. Although not directly fit for reorientation, the two others would help to candidate patients and verify both planning and postoperative result.

High-Temperature Polylactic Acid Proves Reliable and Safe for Manufacturing 3D-Printed Patient-Specific Instruments in Pediatric Orthopedics-Results from over 80 Personalized Devices Employed in 47 Surgeries

(1) Background: Orthopedic surgery has been transformed by 3D-printed personalized instruments (3DP-PSIs), which enhance precision and reduce complications. Hospitals are adopting in-house 3D printing facilities, using cost-effective methods like Fused Deposition Modeling (FDM) with materials like Polylactic acid (PLA) to create 3DP-PSI. PLA's temperature limitations can be overcome by annealing High-Temperature PLA (ann-HTPLA), enabling steam sterilization without compromising properties. Our study examines the in vivo efficacy of ann-HTPLA 3DP-PSI in pediatric orthopedic surgery. (2) Methods: we investigated safety and efficacy using ann-HTPLA 3DP-PSI produced at an "in-office" 3D-printing Point-of-Care (3DP-PoC) aimed at correcting limb deformities in pediatric patients. Data on 3DP-PSI dimensions and printing parameters were collected, along with usability and complications. (3) Results: Eighty-three ann-HTPLA 3DP-PSIs were utilized in 33 patients (47 bone segments). The smallest guide used measured 3.8 cm3, and the largest measured 58.8 cm3. Seventy-nine PSIs (95.2%; 95% C.I.: 88.1-98.7%) demonstrated effective use without issues. Out of 47 procedures, 11 had complications, including 2 infections (4.3%; 95% CI: 0.5-14.5%). Intraoperative use of 3DP-PSIs did not significantly increase infection rates or other complications. (4) Conclusions: ann-HTPLA has proven satisfactory usability and safety as a suitable material for producing 3DP-PSI in an "in-office" 3DP-PoC.

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.

3D-assisted corrective osteotomies of the distal radius: a comparison of pre-contoured conventional implants versus patient-specific implants

PURPOSE

There is a debate whether corrective osteotomies of the distal radius should be performed using a 3D work-up with pre-contoured conventional implants (i.e., of-the-shelf) or patient-specific implants (i.e., custom-made). This study aims to assess the postoperative accuracy of 3D-assisted correction osteotomy of the distal radius using either implant.

METHODS

Twenty corrective osteotomies of the distal radius were planned using 3D technologies and performed on Thiel embalmed human cadavers. Our workflow consisted of virtual surgical planning and 3D printed guides for osteotomy and repositioning. Subsequently, left radii were fixated with patient-specific implants, and right radii were fixated with pre-contoured conventional implants. The accuracy of the corrections was assessed through measurement of rotation, dorsal and radial angulation and translations with postoperative CT scans in comparison to their preoperative virtual plan.

RESULTS

Twenty corrective osteotomies were executed according to their plan. The median differences between the preoperative plan and postoperative results were 2.6° (IQR: 1.6-3.9°) for rotation, 1.4° (IQR: 0.6-2.9°) for dorsal angulation, 4.7° (IQR: 2.9-5.7°) for radial angulation, and 2.4 mm (IQR: 1.3-2.9 mm) for translation of the distal radius, thus sufficient for application in clinical practice. There was no significant difference in accuracy of correction when comparing pre-contoured conventional implants with patient-specific implants.

CONCLUSION

3D-assisted corrective osteotomy of the distal radius with either pre-contoured conventional implants or patient-specific implants results in accurate corrections. The choice of implant type should not solely depend on accuracy of the correction, but also be based on other considerations like the availability of resources and the preoperative assessment of implant fitting.

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.

Virtual Surgical Planning and Patient-Specific Instruments for Correcting Lower Limb Deformities in Pediatric Patients: Preliminary Results from the In-Office 3D Printing Point of Care

(1) Background: Virtual reality and 3D printing are transforming orthopedic surgery by enabling personalized three-dimensional (3D) models for surgical planning and Patient-Specific Instruments (PSIs). Hospitals are establishing in-house 3D printing centers to reduce costs and improve patient care. Pediatric orthopedic surgery also benefits from these technologies, enhancing the precision and personalization of treatments. This study presents preliminary results of an In-Office 3D Printing Point of Care (PoC), outlining considerations and challenges in using this program for treating lower limb deformities in pediatric patients through Virtual Surgical Planning (VSP) and 3D-printed Patient-Specific Instruments (PSIs). (2) Materials and Methods: Pediatric patients with congenital or acquired lower limb deformities undergoing surgical correction based on VSP, incorporating 3D-printed PSIs when required, were included in this study. The entire process of VSP and 3D printing at the In-Office PoC was illustrated. Data about deformity characteristics, surgical procedures, and outcomes, including the accuracy of angular correction, surgical times, and complications, were reported. (3) Results: In total, 39 bone correction procedures in 29 patients with a mean age of 11.6 ± 4.7 years (range 3.1-18.5 years) were performed according to VSP. Among them, 23 procedures were accomplished with PSIs. Surgeries with PSIs were 45 min shorter, with fewer fluoroscopy shots. Optimal correction was achieved in 37% of procedures, while the remaining cases showed under-corrections (41%) or over-corrections (22%). Major complications were observed in four patients (13.8%). (4) Conclusions: The In-Office 3D Printing Point of Care is becoming an essential tool for planning and executing complex corrections of lower limb deformities, but additional research is needed for optimizing the prediction and accuracy of the achieved corrections.

Ipsilateral Concurrent Knee Arthroplasty and Tibial Osteotomy with 3D-Printed Patient-Specific Instrumentation: A Case Report

CASE

A 70-year-old woman presented with knee pain and instability and was diagnosed with advanced knee osteoarthritis and bifocal tibial deformities. The complexity of the case challenged our team to perform a significant sagittal correction (>60°) and restore her ability to walk independently. We performed ipsilateral total knee arthroplasty and anterior closed wedge tibial osteotomy using virtual planning and 3D-printed patient-specific instrumentation.

CONCLUSION

Using 2 separate 3D-printed patient-specific cutting guides for this patient with a complex deformity and managing the whole planning process in close collaboration between the surgeons and engineers resulted in a satisfactory postoperative outcome, optimal implant positioning and leg alignment, and minimal soft-tissue damage.

3D Printing Technology in Pediatric Orthopedics: a Primer for the Clinician

PURPOSE OF REVIEW

This article reviews the basics of 3D printing and provides an overview of current and future applications of this emerging technology in pediatric orthopedic surgery.

RECENT FINDINGS

Both preoperative and intraoperative utilization of 3D printing technology have enhanced clinical care. Potential benefits include more accurate surgical planning, shortening of a surgical learning curve, decrease in intraoperative blood loss, less operative time, and fluoroscopic time. Furthermore, patient-specific instrumentation can be used to improve the safety and accuracy of surgical care. Patient-physician communication can also benefit from 3D printing technology. 3D printing is rapidly advancing in the field of pediatric orthopedic surgery. It has the potential to increase the value of several pediatric orthopedic procedures by enhancing safety and accuracy while saving time. Future efforts in cost reduction strategies, making patient-specific implants including biologic substitutes and scaffolds, will further increase the relevance of 3D technology in the field of pediatric orthopedic surgery.

Virtual Surgical Planning, 3D-Printing and Customized Bone Allograft for Acute Correction of Severe Genu Varum in Children

Complex deformities of lower limbs are frequent in children with genetic or metabolic skeletal disorders. Early correction is frequently required, but it is technically difficult and burdened by complications and recurrence. Herein, we described the case of a 7-year-old girl affected by severe bilateral genu varum due to spondyloepiphyseal dysplasia. The patient was treated by patient-specific osteotomies and customized structural wedge allograft using Virtual Surgical Planning (VSP) and 3D-printed patient-specific instrumentation (PSI). The entire process was performed through an in-hospital 3D-printing Point-of-Care (POC). VSP and 3D-printing applied to pediatric orthopedic surgery may allow personalization of corrective osteotomies and customization of structural allografts by using low-cost in-hospital POC. However, optimal and definitive alignment is rarely achieved in such severe deformities in growing skeleton through a single operation.

Implementation of an In-House 3D Manufacturing Unit in a Public Hospital’s Radiology Department

Objective: Three-dimensional printing has become a leading manufacturing technique in healthcare in recent years. Doubts in published studies regarding the methodological rigor and cost-effectiveness and stricter regulations have stopped the transfer of this technology in many healthcare organizations. The aim of this study was the evaluation and implementation of a 3D printing technology service in a radiology department. Methods: This work describes a methodology to implement a 3D printing service in a radiology department of a Spanish public hospital, considering leadership, training, workflow, clinical integration, quality processes and usability. Results: The results correspond to a 6-year period, during which we performed up to 352 cases, requested by 85 different clinicians. The training, quality control and processes required for the scaled implementation of an in-house 3D printing service are also reported. Conclusions: Despite the maturity of the technology and its impact on the clinic, it is necessary to establish new workflows to correctly implement them into the strategy of the health organization, adjusting it to the needs of clinicians and to their specific resources. Significance: This work allows hospitals to bridge the gap between research and 3D printing, setting up its transfer to clinical practice and using implementation methodology for decision support.

A Two-Step Approach for 3D-Guided Patient-Specific Corrective Limb Osteotomies

Background: Corrective osteotomy surgery for long bone anomalies can be very challenging since deformation of the bone is often present in three dimensions. We developed a two-step approach for 3D-planned corrective osteotomies which consists of a cutting and reposition guide in combination with a conventional osteosynthesis plate. This study aimed to assess accuracy of the achieved corrections using this two-step technique. Methods: All patients (≥12 years) treated for post-traumatic malunion with a two-step 3D-planned corrective osteotomy within our center in 2021 were prospectively included. Three-dimensional virtual models of the planned outcome and the clinically achieved outcome were obtained and aligned. Postoperative evaluation of the accuracy of performed corrections was assessed by measuring the preoperative and postoperative alignment error in terms of angulation, rotation and translation. Results: A total of 10 patients were included. All corrective osteotomies were performed according to the predetermined surgical plan without any complications. The preoperative deformities ranged from 7.1 to 27.5° in terms of angulation and 5.3 to 26.1° in terms of rotation. The achieved alignment deviated on average 2.1 ± 1.0 and 3.4 ± 1.6 degrees from the planning for the angulation and rotation, respectively. Conclusions: A two-step approach for 3D-guided patient-specific corrective limb osteotomies is reliable, feasible and accurate.

From Three-Dimensional (3D)- to 6D-Printing Technology in Orthopedics: Science Fiction or Scientific Reality?

Over the past three decades, additive manufacturing has changed from an innovative technology to an increasingly accessible tool in all aspects of different medical practices, including orthopedics. Although 3D-printing technology offers a relatively inexpensive, rapid and less risky route of manufacturing, it is still quite limited for the fabrication of more complex objects. Over the last few years, stable 3D-printed objects have been converted to smart objects or implants using novel 4D-printing systems. Four-dimensional printing is an advanced process that creates the final object by adding smart materials. Human bones are curved along their axes, a morphological characteristic that augments the mechanical strain caused by external forces. Instead of the three axes used in 4D printing, 5D-printing technology uses five axes, creating curved and more complex objects. Nowadays, 6D-printing technology marries the concepts of 4D- and 5D-printing technology to produce objects that change shape over time in response to external stimuli. In future research, it is obvious that printing technology will include a combination of multi-dimensional printing technology and smart materials. Multi-dimensional additive manufacturing technology will drive the printing dimension to higher levels of structural freedom and printing efficacy, offering promising properties for various orthopedic applications.

Effects of degree of translation or rotation of acetabular fragment of periacetabular osteotomy procedure on pelvic X-ray parameters

The present study aims to investigate the effect of amount of lateralization and/or anteversion of the point where the iliac cut meets with the posterior column cut of periacetabular osteotomy (PAO), on X-ray parameters such as Center of edge (CE) angle, retroversion index (RVI) and sharp angle. Fourteen patients with symptomatic hip dysplasia (CE° < 20°) were included. Pelvis Computerized tomography (CT) sections were used for 3D printing. PAO was then performed on these models. The point (A), 1 cm lateral to the pelvic brim, is marked where the iliac cut intersects the posterior column cut. In Group I (1.5–0), point A is lateralized parallel to the osteotomy line for 1.5 cm. In Group II (1.5–0.5), it is additionally anteverted for 0.5 cm. In Group III (3–0), point A is lateralized for 3 cm and then additionally anteverted for 1 cm (Group IV: 3–1). Radiographs were taken in each stage. The lateral CE angle, RVI and sharp angle were measured. All had an increase in the CE angle and RVI and a decrease in the sharp angle compared to the control group (P < 0.05). The amount of CE angle (ΔCE) or RVI increase (ΔRV) was as follows: 3–1(38°, 0.3) > 3–0(27°, 0.2) and 1.5–0.5(25°, 0.1) > 1.5–0(17°, 0.07) (P < 0.05) (with no difference between groups 1.5–0.5 and 3–0, P = 0.7). The amount of sharp angle decrease was as follows: 3–1(20°), 3–0(18°) < 1.5–0.5(11°) < 1.5–0(8°) (P < 0.05). The lateralization of the intersection point where the iliac wing cut meets with the posterior column cut along the cut surface led to an increase of lateral cover and focal retroversion. Additional anteversion leads to further increases in those parameters, while groups 1.5–0.5 and 3–0 did not differ between.

Forearm segmental bone defect: Successful management using the Masquelet Technique with the aid of 3D printing technology

The management of forearm nonunion is challenging for orthopaedic surgeons because the forearm is a unique anatomical segment in which all the bones and structures involved embody a complex functional unit. Therefore, when treating such a complex condition, the surgeon must focus not only on bone healing but also on the restoration of the native anatomy in order to replicate the normal relationship between the bones and all the surrounding structures and thus the full function of the forearm, the elbow and the wrist.

Here we report the case of a 53-year-old patient with a left forearm deformity due to an atrophic nonunion of the ulna and a malunion of the radius, which was successfully managed with the use of the Masquelet technique associated with a corrective osteotomy of the radius, performed with the aid of a 3D model.

Patient-Specific Guided Osteotomy to Correct a Symptomatic Malunion of the Left Forearm

We present a case report of a 12-year old female with a midshaft forearm fracture. Initial conservative treatment with a cast failed, resulting in a malunion. The malunion resulted in functional impairment for which surgery was indicated. A corrective osteotomy was planned using 3D analyses of the preoperative CT-scan. Subsequently, patient-specific guides were printed and used during the procedure to precisely correct the malunion. Three months after surgery, the radiographs showed full consolidation and the patient was pain-free with full range of motion and comparable strength in both forearms. The current case report shows that a corrective osteotomy with patient-specific guides based on preoperative 3D analyses can help surgeons to plan and precisely correct complex malunions resulting in improved functional outcomes.