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

Three-dimensional imaging of the forearm and hand: A comparison between two 3D imaging systems

The conventional treatment for distal radius fractures typically involves immobilization of the injured extremity using a conventional forearm cast. These casts do cause all sorts of discomfort during wear and impose life-style restrictions on the wearer. Personalized 3D printed splints, designed using three-dimensional (3D) imaging systems, might overcome these problems. To obtain a patient specific splint, commercially available 3D camera systems are utilized to capture patient extremities, generating 3D models for splint design. This study investigates the feasibility of utilizing a new camera system (SPENTYS) to capture 3D surface scans of the forearm for the design of 3D printed splints. In a prospective observational cohort study involving 17 healthy participants, we conducted repeated 3D imaging using both the new (SPENTYS) and a reference system (3dMD) to assess intersystem accuracy and repeatability. The intersystem accuracy of the SPENTYS system was determined by comparison of the 3D surface scans with the reference system (3dMD). Comparison of consecutive images acquired per device determined the repeatability. Feasibility was measured with system usability score questionnaires distributed among professionals. The mean absolute difference between the two systems was 0.44 mm (SD:0.25). The mean absolute difference of the repeatability of the reference -and the SPENTYS system was respectively 0.40 mm (SD: 0.30) and 0.53 mm (SD: 0.25). Both repeatability and intersystem differences were within the self-reported 1 mm. The workflow was considered easy and effective, emphasizing the potential of this approach within a workflow to obtain patient specific splint.

In-house 3D-printed custom splints for non-operative treatment of distal radial fractures: a randomized controlled trial

We compared patient satisfaction and clinical effectiveness of 3D-printed splints made of photopolymer resin to conventional fibre glass casts in treating distal radial fractures. A total of 39 patients with minimally displaced distal radius fractures were included and randomized. Of them, 20 were immobilized in a fibre glass cast and 19 in a 3D-printed forearm splint. The 3D-printed splints were custom-designed based on forearm surface scanning with a handheld device and printed in-house using digital light processing printing technology. Patient satisfaction and clinical effectiveness were assessed with questionnaires 1 and 6 weeks after the initiation of immobilization. Fracture healing, pain, range of motion, grip strength and the DASH and PRWE scores were assessed up to 1-year follow-up. 3D-printed splints proved to be equally well tolerated by the patients and equally clinically effective as conventional fibre glass casts although there was a higher rate of minor complications. 3D-printed splints present a safe alternative, especially in young, active patients, for non-operative treatment of distal radial fractures.Level of evidence: I.

Clinical application of instant 3D printed cast versus polymer orthosis in the treatment of colles fracture: a randomized controlled trial

BACKGROUND

The shortcomings of plaster in water resistance, air permeability, skin comfort, fixed stability and weight of wearing are still to be solved. 3D printed cast can overcome the above shortcomings. At present, there is a relative lack of data on the clinical application of 3D printed cast, probably due to its complexity, relatively long operating time, and high price. We aimed to compare and evaluate the short-term effectiveness, safety and advantages of 3D printed wrist cast versus polymer orthosis in the treatment of Colles fracture.

METHODS

Forty patients with Colles fracture in our hospital from June to December 2022 were selected and divided into an observation group (20 patients, treated with instant 3D printed cast) and a control group (20 cases, treated with polymer orthosis). Both groups treated with manual reduction and external fixation. The visual analogue scale (VAS), immobilization effectiveness and satisfaction scores, Disability of the Arm, Shoulder and Hand (DASH) score, complications and imaging data were collected and compared before immobilization and at 2, 6 and 12 weeks after the fracture.

RESULTS

VAS at 2 weeks after the fracture was significantly lower in the observation group than in the control group ( P < 0.05). The immobilization effectiveness and satisfaction scores at 6 weeks after the fracture were significantly higher in the observation group than in the control group (all P < 0.05). The DASH scores at 2 and 6 weeks after the fracture were significantly lower in the observation group than in the control group (all P < 0.05). There wasn't rupture of the printed cast or orthosis in both groups. There were 2 cases of skin irritation in the control group, and no skin irritation occurred in the observation group. The palmar tilt angle and ulnar inclination angle at 2 weeks and 12 weeks after the fracture were significantly higher in the observation group than in the control group (all P < 0.05).

CONCLUSIONS

Both instant 3D printed cast and polymer orthosis are effective in the treatment of Colles fracture. But instant 3D printed cast is better than polymer orthosis in areas of good clinical and imaging performance, and high patient satisfaction and comfort.

Point-of-Care Orthopedic Oncology Device Development

BACKGROUND

The triad of 3D design, 3D printing, and xReality technologies is explored and exploited to collaboratively realize patient-specific products in a timely manner with an emphasis on designs with meta-(bio)materials.

METHODS

A case study on pelvic reconstruction after oncological resection (osteosarcoma) was selected and conducted to evaluate the applicability and performance of an inter-epistemic workflow and the feasibility and potential of 3D technologies for modeling, optimizing, and materializing individualized orthopedic devices at the point of care (PoC).

RESULTS

Image-based diagnosis and treatment at the PoC can be readily deployed to develop orthopedic devices for pre-operative planning, training, intra-operative navigation, and bone substitution.

CONCLUSIONS

Inter-epistemic symbiosis between orthopedic surgeons and (bio)mechanical engineers at the PoC, fostered by appropriate quality management systems and end-to-end workflows under suitable scientifically amalgamated synergies, could maximize the potential benefits. However, increased awareness is recommended to explore and exploit the full potential of 3D technologies at the PoC to deliver medical devices with greater customization, innovation in design, cost-effectiveness, and high quality.

The Upper Limb Orthosis in the Rehabilitation of Stroke Patients: The Role of 3D Printing

Stroke represents the third cause of long-term disability in the world. About 80% of stroke patients have an impairment of bio-motor functions and over half fail to regain arm functionality, resulting in motor movement control disorder with serious loss in terms of social independence. Therefore, rehabilitation plays a key role in the reduction of patient disabilities, and 3D printing (3DP) has showed interesting improvements in related fields, thanks to the possibility to produce customized, eco-sustainable and cost-effective orthoses. This study investigated the clinical use of 3DP orthosis in rehabilitation compared to the traditional ones, focusing on the correlation between 3DP technology, therapy and outcomes. We screened 138 articles from PubMed, Scopus and Web of Science, selecting the 10 articles fulfilling the inclusion criteria, which were subsequently examined for the systematic review. The results showed that 3DP provides substantial advantages in terms of upper limb orthosis designed on the patient's needs. Moreover, seven research activities used biodegradable/recyclable materials, underlining the great potential of validated 3DP solutions in a clinical rehabilitation setting. The aim of this study was to highlight how 3DP could overcome the limitations of standard medical devices in order to support clinicians, bioengineers and innovation managers during the implementation of Healthcare 4.0.

Investigations on the Fatigue Behavior of 3D-Printed and Thermoformed Polylactic Acid Wrist-Hand Orthoses

Additively manufactured wrist-hand orthoses (3DP-WHOs) offer several advantages over traditional splints and casts, but their development based on a patient's 3D scans currently requires advanced engineering skills, while also recording long manufacturing times as they are commonly built in a vertical position. A proposed alternative involves 3D printing the orthoses as a flat model base and then thermoforming them to fit the patient's forearm. This manufacturing approach is faster, cost-effective and allows easier integration of flexible sensors as an example. However, it is unknown whether these flat-shaped 3DP-WHOs offer similar mechanical resistance as the 3D-printed hand-shaped orthoses, with a lack of research in this area being revealed by the literature review. To evaluate the mechanical properties of 3DP-WHOs produced using the two approaches, three-point bending tests and flexural fatigue tests were conducted. The results showed that both types of orthoses had similar stiffness up to 50 N, but the vertically built orthoses failed at a maximum load of 120 N, while the thermoformed orthoses could withstand up to 300 N with no damages observed. The integrity of the thermoformed orthoses was maintained after 2000 cycles at 0.5 Hz and ±2.5 mm displacement. It was observed that the minimum force occurring during fatigue tests was approximately -95 N. After 1100-1200 cycles, it reached -110 N and remained constant. The outcomes of this study are expected to enhance the trust that hand therapists, orthopedists, and patients have in using thermoformable 3DP-WHOs.

Low-Cost Cranioplasty—A Systematic Review of 3D Printing in Medicine

The high cost of biofabricated titanium mesh plates can make them out of reach for hospitals in low-income countries. To increase the availability of cranioplasty, the authors of this work investigated the production of polymer-based endoprostheses. Recently, cheap, popular desktop 3D printers have generated sufficient opportunities to provide patients with on-demand and on-site help. This study also examines the technologies of 3D printing, including SLM, SLS, FFF, DLP, and SLA. The authors focused their interest on the materials in fabrication, which include PLA, ABS, PET-G, PEEK, and PMMA. Three-dimensional printed prostheses are modeled using widely available CAD software with the help of patient-specific DICOM files. Even though the topic is insufficiently researched, it can be perceived as a relatively safe procedure with a minimal complication rate. There have also been some initial studies on the costs and legal regulations. Early case studies provide information on dozens of patients living with self-made prostheses and who are experiencing significant improvements in their quality of life. Budget 3D-printed endoprostheses are reliable and are reported to be significantly cheaper than the popular counterparts manufactured from polypropylene polyester.

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 acceptance of advanced visualization methods: a comparison study of 3D-print, virtual reality glasses, and 3D-display

BACKGROUND

To compare different methods of three-dimensional representations, namely 3D-Print, Virtual Reality (VR)-Glasses and 3D-Display regarding the understanding of the pathology, accuracy of details, quality of the anatomical representation and technical operability and assessment of possible change in treatment in different disciplines and levels of professional experience.

METHODS

Interviews were conducted with twenty physicians from the disciplines of cardiology, oral and maxillofacial surgery, orthopedic surgery, and radiology between 2018 and 2020 at the University Hospital of Basel. They were all presented with three different three-dimensional clinical cases derived from CT data from their area of expertise, one case for each method. During this, the physicians were asked for their feedback written down on a pencil and paper questionnaire.

RESULTS

Concerning the understanding of the pathology and quality of the anatomical representation, VR-Glasses were rated best in three out of four disciplines and two out of three levels of professional experience. Regarding the accuracy of details, 3D-Display was rated best in three out of four disciplines and all levels of professional experience. As to operability, 3D-Display was consistently rated best in all levels of professional experience and all disciplines. Possible change in treatment was reported using 3D-Print in 33%, VR-Glasses in 44%, and 3D-Display in 33% of participants. Physicians with a professional experience of more than ten years reported no change in treatment using any method.

CONCLUSIONS

3D-Print, VR-Glasses, and 3D-Displays are very well accepted, and a relevant percentage of participants with less than ten years of professional work experience could imagine a possible change in treatment using any of these three-dimensional methods. Our findings challenge scientists, technicians, and physicians to further develop these methods to improve the three-dimensional understanding of pathologies and to add value to the education of young and inexperienced physicians.

Utilization of 3D printed orthoses for musculoskeletal conditions of the upper extremity: A systematic review

STUDY DESIGN

Systematic Review INTRODUCTION: 3D printed orthoses are emerging as a possible option in the field of hand therapy to fabricate conventional casts and orthoses. It is unknown how this technology is currently being used to treat upper extremity musculoskeletal conditions, and if 3D orthoses are comparable to custom- made low temperature thermoplastic orthoses fabricated by hand therapists.

PURPOSE OF THE STUDY

The primary aim of this review was to investigate the utilization, effectiveness and feasibility of 3D printed technology to manufacture custom orthoses for musculoskeletal conditions of the upper extremity.

METHODS

Studies describing 3D printed orthoses or casts used in treatment with patients were included following a comprehensive literature search using CINAHL, PubMed, Medline, ProQuest, and EBSCO databases. The selected studies had to address musculoskeletal conditions of the elbow, wrist, hand and/or digits that would typically be immobilized with a cast or brace or orthotic or orthosis.

RESULTS

Ten studies met the inclusion criteria. Study designs included case studies, case series, and 1 randomized clinical trial. 3D printed orthoses/casts appear to be comfortable, provide adequate immobilization, and have pleasing aesthetics. However, expensive equipment, lack of appropriate software and scanning tools and lack of highly skilled clinicians are all factors preventing the implementation of 3D printed orthoses into current clinical practice.

DISCUSSION

3D printed orthoses appear to be effective at immobilization of a limb, aesthetically pleasing, and utilize lightweight and well -ventilated materials. However, the feasibility of implementing 3D printing technology in hand therapy settings remains challenging in part due to the resources required.

CONCLUSIONS

While 3D printing shows promise, the high cost of equipment, lack of training and skill of clinicians and the long time required for production are all factors that need to be improved to make 3D printing a viable option in the hand therapy setting.