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Introduction: Three-dimensional (3D) printing technology has been used in orthopaedic surgery in recent years to manufacture customized surgical cutting jigs. However, there is scarcity of literature and information regarding the optimal parameters of an ideal jig. Our study aims to determine the optimum parameters to design surgical jigs that can produce accurate cuts, and remain practical for use, to serve as a guide for jig creation in future. Methods and materials: A biomechanical lab study was designed to investigate whether the thickness of a jig and the height of its cutting slot can significantly affect cutting accuracy. Surgical jigs were 3D printed in medical grade, and an oscillating sawblade was used to mimic intraoperative surgical cuts through the cutting slots onto wooden blocks, which were then analysed to determine the accuracy of cuts. Results: Statistical analysis was performed on a total of 72 cuts. The cutting accuracy increased when the thickness of the jig increased, at all slot heights. The cutting accuracy also increased as the slot height decreased, at all jig thicknesses. Overall, the parameters for jig construction that yielded the most accurate cuts were a jig thickness of 15 mm, in combination with a slot height of 100 % of the width of the sawblade. Additionally, at a jig thickness of 15 mm, there was no statistically significant difference in cutting accuracy when increasing the slot height to 120 %. Conclusion: This study is the first to propose tangible parameters that can be applied to surgical jig construction to obtain reproducible accurate cuts. Provided that a jig of 15 mm thickness can be accommodated by the size of the wound, the ideal surgical jig with a superior balance of accuracy and useability is 15 mm thick, with a cutting slot height of 120 % of the sawblade thickness.
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BACKGROUND: Spinal metallosis is a rare complication following spinal instrumentation whereby an inflammatory response to the metal implants results in the development of granulomatous tissue. CASE SUMMARY: We describe the case of a 78-year-old woman who had recurrence of back pain 5 years after lumbar spine posterior decompression and instrumented fusion. Lumbar spine radiographs showed hardware loosening and magnetic resonance imaging showed adjacent segment disease. Revision surgery revealed evidence of metallosis intraoperatively. CONCLUSION: Spinal metallosis can present several years after instrumentation. Radiography and computed tomography may demonstrate hardware loosening secondary to metallosis. Blood metal concentrations associated with spinal metallosis have yet to be established. Hence, metallosis is still an intraoperative and histopathological diagnosis. The presence of metallosis after spinal instrumentation likely indicates a more complex underlying problem: Pseudarthrosis, failure to address sagittal balance, infection, and cross-threading of set screws. Hence, identifying metallosis is important, but initiating treatment promptly for symptomatic implant loosening is of greater paramount.
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BACKGROUND: Reverse shoulder arthroplasty (RSA), first introduced as a management option for cuff tear arthropathy, is now an accepted treatment for complex proximal humeral fractures. Few studies have identified whether the outcomes of RSA for shoulder trauma are comparable to those of RSA for shoulder arthritis. METHODS: This is a retrospective, single-institution cohort study of all patients who underwent RSA at our institution between January 2013 and December 2019. In total, 49 patients met the inclusion criteria. As outcomes, we evaluated the 1-year American Shoulder and Elbow Surgeons (ASES) and Constant shoulder scores, postoperative shoulder range of motion, intra- and postoperative complications, and cumulative revision rate. The patients were grouped based on preoperative diagnosis to compare postoperative outcomes across two broad groups. RESULTS: The median follow-up period was 32.8 months (interquartile range, 12.6-66.6 months). The 1-year visual analog scale, range of motion, and Constant and ASES functional scores were comparable between RSAs performed to treat shoulder trauma and that performed for arthritis. The overall complication rate was 20.4%, with patients with a preoperative diagnosis of arthritis having significantly more complications than those with a preoperative diagnosis of trauma (34.8% vs. 7.7%). CONCLUSIONS: Patients who underwent RSA due to a proximal humeral fracture or dislocation did not fare worse than those who underwent RSA for arthritis at 1 year, in terms of both functional and radiological outcomes.
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BACKGROUND: Intramedullary nail fixation is currently the modality of choice in surgical treatment for atypical femoral fractures (AFF). Its uses are limited, however, in severely bowed femurs, narrow medullary canals, or in the presence of thick endosteal callus at the apex of the femoral curve. In these cases, extramedullary plate osteosynthesis is preferred. The consideration when adopting plate osteosynthesis is whether a short or long segment fixation is superior. We hypothesize that a long segment fixation has the potential advantage of protecting the entire length of the femur from future fractures in the adynamic bone. In this series, we present two cases from our institution, with the aims of discussing the benefits and limitations of short versus long segment plate fixation in AFF. CASE SUMMARY: We report two uncommon cases of bisphosphonate-related AFF in two Asian patients with severe femoral curvature, who were treated with extramedullary plate osteosynthesis at our institution. One patient underwent fixation with a short segment plate osteosynthesis, and the other received a long plate osteosynthesis spanning the proximal to distal femur in an attempt to protect the bone from future fractures. Both patients showed a favourable and uncomplicated course post-surgery, with early return to ambulation and radiographic bone union at follow up. CONCLUSION: We expect to see an increase in the number of patients with AFF and bowed femurs, especially with the increased usage of bisphosphonates given an ageing Asian population. Surgical treatment with short and long plate osteosynthesis are options with their own advantages and limitations. With the advent of new anatomical plate options, long segment fixation has become more accessible and may be considered in this patient group as it has the potential advantage of protecting the adynamic femur from future fractures. Further studies should be targeted to determine which method of treatment is superior in this particular group of patients.
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INTRODUCTION: Multi-planar external fixation is used for the management of complex distal tibia fractures. This study aims to describe our experience of treating distal tibia fractures using the Ilizarov, Taylor Spatial Frame and True-Lok Hex external fixation methods. METHODOLOGY: We conducted a retrospective analysis of clinical and radiological records of all distal tibia fractures that were managed with multi-planar external fixation over a period of 3 years. A total of 13 cases were included, of which most were high-energy injuries. RESULTS: The average age of the patients was 44 years old. 11 (85%) cases were high-energy trauma due to road traffic accidents. 8 (62%) cases involved the revision of a previous fixation method. Most (77%) cases were AO classification Type 3, and the majority (62%) of cases were open fractures. The average duration in the external fixator frame and time to radiological union was 5 months and 6 months respectively. The average malalignment at union was 1.3 degrees and 0.5 degrees in the coronal plane and sagittal plane respectively. All fractures involving the joint line were adequately restored. There were 2 (16%) case of non-union and 2 (15%) cases of pin site infections. 1 case required a corticotomy and subsequent lengthening. CONCLUSION: Multi-planar circular external fixation is a reliable method to treat complex distal tibia fractures, both in the acute setting and as revision surgery. The rates of fracture union is high, with minimal malalignment. Although pin site infections are relatively common, they are uncomplicated and easily treated.