Intraoperative manufacturing of patient specific instrumentation for shoulder arthroplasty: a novel mechatronic approach

Optimal orthopaedic implant placement is a major contributing factor to the long term success of all common joint arthroplasty procedures. Devices such as three-dimensional (3D) printed, bespoke guides and orthopaedic robots are extensively described in the literature and have been shown to enhance prosthesis placement accuracy. These technologies, however, have significant drawbacks, such as logistical and temporal inefficiency, high cost, cumbersome nature and difficult theatre integration. A new technology for the rapid intraoperative production of patient specific instrumentation, which overcomes many of the disadvantages of existing technologies, is presented here. The technology comprises a reusable table side machine, bespoke software and a disposable element comprising a region of standard geometry and a body of mouldable material. Anatomical data from Computed Tomography (CT) scans of 10 human scapulae was collected and, in each case, the optimal glenoid guidewire position was digitally planned and recorded. The achieved accuracy compared to the preoperative bespoke plan was measured in all glenoids, from both a conventional group and a guided group. The technology was successfully able to intraoperatively produce sterile, patient specific guides according to a pre-operative plan in 5 minutes, with no additional manufacturing required prior to surgery. Additionally, the average guide wire placement accuracy was 1.58 mm and 6.82◦ degrees in the manual group, and 0.55 mm and 1.76◦ degrees in the guided group, also demonstrating a statistically significant improvement

VITAL: an IDEAL stage 2b feasibility study of a randomised controlled trial evaluating whether virtual reality technology can improve surgical training in Sierra Leone

Background: Training surgeons is costly and resource intensive, often requiring extended periods of expert supervision. Virtual reality (VR) has shown potential in enhancing surgical skill acquisition, but its use in low- and middle-income countries (LMICs) remains limited. This study aimed to evaluate the feasibility of using smartphone VR for surgical training in LMICs. Methods: We conducted a prospective randomised controlled feasibility study involving surgical trainees recruited from a government teaching hospital in Freetown, Sierra Leone. Participants were randomised 1:1 VR vs non-VR and received a 2-day hands-on course on lower limb amputation. The VR group received additional VR training consisting of two 30-minute modules with narrated live surgery videos. Feasibility outcomes included recruitment rates, VR intervention adherence, fidelity and acceptability. Results: A total of 30 participants were randomised, 15 to the VR group and 15 to the control group. The recruitment period lasted 2 days, and 29 participants (96.7%) completed the course. The VR intervention had high fidelity and acceptability, with 100% of participants completing the intervention. There was no unblinding. Compared to the control group, the VR group reported statistically significantly higher engagement during the hands-on course. Conclusion: Our findings suggest that smartphone VR is technically feasible for surgical training in LMICs, and may improve engagement and perceived learning. With minor modifications to the intervention and assessments, a larger-scale trial is feasible. These results highlight the potential for VR to address the challenges of surgical training in LMICs, where access to expert supervision and costly training resources may be limited

A Stakeholder-Informed Approach to the Identification of Criteria for the Prioritization of Zoonoses in Canada

Background: Zoonotic diseases account for over 60 % of all communicable diseases causing illness in humans and 75 % of recently emerging infectious diseases. As limited resources are available for the control and prevention of zoonotic diseases, it is necessary to prioritize diseases in order to direct resources into those with the greatest needs. The selection of criteria for prioritization has traditionally been on the basis of expert opinion; however, details of the methods used to identify criteria from expert opinion often are not published and a full range of criteria may not be captured by expert opinion. Methodology/Principal Findings: This study used six focus groups to identify criteria for the prioritization of zoonotic diseases in Canada. Focus groups included people from the public, animal health professionals and human health professionals. A total of 59 criteria were identified for prioritizing zoonotic diseases. Human-related criteria accounted for the highest proportion of criteria identified (55%), followed by animal-related criteria (26%) then pathogen/disease-related criteria (19%). Similarities and differences were observed in the identification and scoring of criteria for disease prioritization between groups; the public groups were strongly influenced by the individual-level of disease burden, the responsibility of the scientific community in disease prioritization and the experiences of recent events while the professional groups were influenced by the societal- and population-level of disease burden and political and public pressure

Towards a commercial system for intraoperative manufacture of patient-specific guides for shoulder arthroplasty

The accurate placement of orthopaedic implants according to a biomechanically derived preoperative plan is an important consideration in the long-term success of these interventions. Guidance technologies are widely described however, high cost, complex theatre integration, intraoperative inefficiency and functional limitations have prevented the widespread use. A novel, intraoperative mechatronics platform is presented, capable of the rapid, intraoperative manufacture of low-cost patient-specific guides. The device consists of a tableside robot with sterile drapes and some low cost, sterile disposable components. The robot comprises a 3D optical scanner, a three-axis sterile computer numerical control (CNC) drill and a two-axis receptacle into which the disposable consumables may be inserted. The sterile consumable comprises a region of rapidly setting moldable material and a clip allowing it to be reversibly attached to the tableside robot. In use, patient computed tomography (CT) imaging is obtained at any point prior to surgery and a surgical plan is created on associated software. This plan describes the axis and positioning of one or more guidewires which may, in turn, locate the prosthesis into position. Intraoperatively, osseous anatomy is exposed, and the sterile disposable is used to rapidly create a mould of the joint surface. Once set, the mould is inserted into the robot and an optical scan of the surface is taken followed by automatic surface registration, bringing the optical scan into the same coordinate frame of reference as the CT data and plan. The CNC drill is orientated such that the drill axis and position exactly matches the planned axis and position with respect to the moulded surface. A guide hole is drilled into the mould blank, which is removed from the robot and placed back into the patient with the moulded surface ensuring exact replacement. A wire is subsequently driven through the guide hole into the osseous anatomy in accordance with the preoperative plan. The guide blank may be slid off the wire and discarded allowing the procedure to continue in the normal manner. A Pre-clinical prototype robot was constructed and used to insert guide wires into a 12 cadaveric shoulder arthroplasty specimens according to a ‘pre-operative’ plan. A ‘postoperative’ CT scan was used to assess accuracy with respect to the ‘pre-operative’ plan. Initial average end to end accuracy was 1.2 mm with respect to planned vs achieved glenoid point of entry and 2.2deg version, 1.6deg inclination with respect to planned vs achieved wire angle. These data demonstrate accuracy within the bounds of relevant literature with a significant margin for potential improvement