The addition of 3D printed models to enhance the teaching and learning of bone spatial anatomy and fractures for undergraduate students: a randomized controlled study

3D printing in hand surgery

While 3D printing in hand surgery is still in its infancy, it offers new avenues in research, teaching, and personalized medicine. For these reasons, some surgeons may want to jump on the bandwagon of this trendy technology. But we cannot forget that its superiority over conventional techniques has not been demonstrated. Surgeons who want to work with 3D printed objects must master their use and the entire manufacturing process, otherwise they risk becoming dependent on engineers and/or medical device companies.

[3D printing in orthopedic and trauma surgery education and training : Possibilities and fields of application]

The 3D printing technology enables precise fracture models to be generated from volumetric digital imaging and communications in medicine (DICOM) computed tomography (CT) data. Apart from patient treatment, in the future this technology could potentially play a significant role in education and training in the field of orthopedic and trauma surgery. Preliminary results show that the understanding and classification of fractures can be improved when teaching medical students. The use of life-size and haptic models of real fractures for education is particularly interesting. Even experienced surgeons show an improved classification and treatment planning with the help of 3D printed models when compared to plain CT data. Especially for complex articular fractures, such as those of the acetabulum and tibial plateau, initial evidence shows patient benefits in terms of reduced surgery time and blood loss with the help of 3D models. The use of 3D printing on-site at the hospital is of particular interest in orthopedic and trauma surgery as it promises to provide products within a short time. The low investment and running costs and the increasing availability of convenient software solutions will spur increasing dissemination of this technology in the coming years.

A novel approach using 3-D printing in the Irish National Centre for pelvic and acetabular surgery

BACKGROUND

Complex pelvic fractures present the orthopaedic surgeon with many challenges. 3-D printed models may provide assistance in pre-operative planning, may lead to improvements in intra-operative (i) decision making and (ii) efficiencies (time reduction, blood loss reduction, screening reduction) and may result in improvements in post-operative outcomes (fracture reduction & quality of life). The models also provide hands-on opportunities for orthopaedic trainees and patients. This may result in improvements in (i) education/training regarding the management of pelvic and acetabular fractures for orthopaedic trainees and (ii) improvements in patient consenting and overall patient satisfaction.

DESIGN

Single-centre, two orthopaedic surgeons (pelvic and acetabular fellowship trained), prospective observational study. Twenty patients with acute displaced pelvic/acetabular fracture(s); ten 3-D-printed pelvis and ten non-printed cases for comparison. The comparison cohorts were matched for fracture classification, sex and age.

OUTCOME MEASURES

Classification assistance, intra-operative time, estimated blood loss, screening amount, post-operative reduction and infection, EQ-5D-5L, teaching/educational assistance and pre-operative counselling.

RESULTS

The models provided more information regarding fracture pattern, however, this did not result in change of CT-planned approach/procedure or patient outcomes. The models scored highly on surgeon's questionnaire. The models were found to have a positive impact on trainee education and patient consenting/counselling. With regard to objective comparisons, there was no significant improvements in time-to-surgery, intra-operative time, estimated blood loss, screening amount, fracture reduction or infection rate. There was no significant difference in quality of life questionnaire ~ 12 months post-surgery (statistical tests used; Cohen's effect size and Fisher's exact test).

CONCLUSIONS

Whilst the authors recognize the positive subjective findings with respect to the use of 3-D printing in pelvic and acetabular trauma in our National Centre, objective findings were lacking.

Use of 3D printed models in student education of craniofacial traumas

A low-cost 3D printed model has been introduced into the oral and maxillofacial surgery teaching program of undergraduate students to improve education and mechanical comprehension of craniofacial trauma. Steps of the 3D printed haptic model building process are listed. 3D printed models of facial fractures were obtained from Data Imaging and Communications in Medicine (DICOM) data. Computed Aided Design and Manufacturing (CAD-CAM) freeware was used to create new fractures on the standard tessellation language (STL) file. 3D printed haptic model appears to be an efficient low-cost support for craniofacial trauma education of undergraduate students.

The Future of Biomechanical Spine Research: Conception and Design of a Dynamic 3D Printed Cervical Myelography Phantom

Background

Three-dimensional (3D) printing is a growing practice in the medical community for patient care and trainee education as well as production of equipment and devices. The development of functional models to replicate physiologic systems of human tissue has also been explored, although to a lesser degree. Specifically, the design of 3D printed phantoms that possess comparable biomechanical properties to human cervical vertebrae is an underdeveloped area of spine research. In order to investigate the functional uses of cervical 3D printed models for replicating the complex physiologic and biomechanical properties of the human subaxial cervical spine, our institution has created a prototype that accurately reflects these properties and provides a novel method of assessing spinal canal dimensions using simulated myelography. To our knowledge, this is the first 3D printed phantom created to study these parameters.

Materials and methods

A de-identified cervical spine computed tomography imaging file was segmented using threshold modulation in 3D Slicer software. The subaxial vertebrae (C3-C7) of the scan were individualized by separating the facet joint spaces and uncovertebral joints within the software in order to create individual stereolithography (STL) files. Each individual vertebra was printed on an Ultimaker S5 dual-extrusion printer using white “tough” polylactic acid filament. A human cadaveric subaxial cervical spine was harvested to provide a control for our experiment. Both models were assessed and compared in flexion and extension dynamic motion grossly and fluoroscopically. The maximum angles of deformation on X-ray imaging were recorded using DICOM (Digital Imaging and Communications in Medicine) viewing software. In order to compare the ability to assess canal dimensions of the models using fluoroscopic imaging, a myelography simulation was designed.

Results

The cervical phantom demonstrated excellent ability to resist deformation in flexion and extension positions, attributed to the high quality of initial segmentation. The gross and fluoroscopic dynamic movement of the phantom was analogous to the cadaver model. The myelography simulator adequately demonstrated the canal dimensions in static and dynamic positions for both models. Pertinent anatomic landmarks were able to be effectively visualized for assessment of canal measurements for sagittal and transverse dimensions.

Conclusions

By utilizing the latest technologies in DICOM segmentation and 3D printing, our institution has created the first cervical myelography phantom for biomechanical evaluation and trainee instruction. By combining new technologies with anatomical knowledge, quality 3D printing shows great promise in becoming a standard player in the future of spinal biomechanical research.