Background External fixators are complex, expensive orthopaedic devices used to stabilize high-energy and complex fractures of the extremities. Although the technology has advanced dramatically over the last several decades, the mechanical goals for fracture stabilization of these devices have remained unchanged. Three-dimensional (3D) printing technology has the potential to advance the practice and access to external fixation devices in orthopaedics. This publication aims to systematically review and synthesize the current literature on 3D printed external fixation devices for managing orthopaedic trauma fractures. Methods The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocols were followed for this manuscript with minor exceptions. PubMed, Embase, Cochrane Review, Google Scholar, and Scopus online databases were systematically searched. Two independent reviewers screened the search results based on predetermined inclusion and exclusion criteria related to 3D printing and external fixation of fractures. Results Nine studies met the inclusion criteria. These included one mechanical testing study, two computational simulation studies, three feasibility studies, and three clinical case studies. Fixator designs and materials varied significantly between authors. Mechanical testing revealed similar strength to traditional metal external fixators. Across all clinical studies, five patients underwent definitive treatment with 3D printed external fixators. They all had satisfactory reduction and healing with no reported complications. Conclusions The current literature on this topic is heterogeneous, with highly variable external fixator designs and testing techniques. A small and limited number of studies in the scientific literature have analyzed the use of 3D printing in this area of orthopaedic surgery. 3D printed external fixation design advancements have yielded promising results in several small clinical case studies. However, additional studies on a larger scale with standardized testing and reporting techniques are needed.

Background: Post-traumatic syringomyelia (PTS) is an uncommon complication of spinal cord injury (SCI) characterized by development of a fluid filled cavity in the spinal cord parenchyma. Presentation involves pain, weakness, and abnormal reflexes. There are few known triggers for disease progression. We present a case of symptomatic PTS that appears to have been triggered by parathyroidectomy. Case Description: A 42-year-old female with a distant history of SCI developed clinical and imaging findings consistent with acute expansion of PTS immediately following parathyroidectomy. Her symptoms included acute numbness, tingling, and pain in both arms. Magnetic resonance imaging (MRI) revealed a syrinx in the cervical and thoracic spinal cord. However, this was initially misdiagnosed as transverse myelitis and was treated as such without resolution of symptoms. Over the following 6 months, the patient experienced progressive weakness. Repeat MRI demonstrated expansion of the syrinx with new involvement of the brain stem. The patient was diagnosed with PTS and referred for outpatient neurosurgery evaluation at a tertiary facility. Treatment was delayed due to problems with housing and scheduling at the outside facility, allowing for continued worsening of her symptoms. The syrinx was surgically drained and a syringo-subarachnoid shunt was placed. Follow-up MRI confirmed correct placement of the shunt as well as resolved syrinx and decreased thecal sac compression. The procedure effectively halted symptom progression but did not resolve all symptoms completely. The patient has regained her ability to perform much of her activities of daily living but remains in a nursing home facility. Conclusion: There are currently no cases of PTS expansion following non-central nervous system surgery reported in the literature. The reason for PTS expansion following parathyroidectomy in this case is unknown but may highlight the need for extra caution when intubating or positioning a patient with a history of SCI.

Background: Pyoderma gangrenosum (PG) is a rare autoinflammatory skin disorder that presents with extremely painful ulcerative skin lesions. Bullous PG is a rare subtype, characterized by formation of large hemorrhagic bullae. The bullous subtype is especially uncommon in children. We present here a case of bullous PG in a young Native American male. Case Presentation: A 12-year-old previously healthy Native American male initially developed several pustules on his back and axilla. Over the following three days, the lesions expanded into large hemorrhagic bullae. Suspecting an infectious etiology, he was initially treated with oral and topical antibiotics. The lesions continued to grow in size and number, and some developed into deep ulcerations. Antibiotic coverage was broadened, and he was admitted to a local hospital. The lesions progressed to include all four extremities, the torso, and deep ulcerations of the bilateral axillae. He was transferred to a higher-level facility for further workup. The diagnosis of bullous pyoderma gangrenosum was then made based on histologic findings of neutrophilic infiltration of the dermis and negative workup for other conditions. He was initially treated with systemic corticosteroids with immediate improvement. He continued to experience extreme pain, necessitating PICU admission for sedation during dressing changes. After three weeks, the lesions had healed significantly. He was given an infusion of Infliximab and discharged home. Two months after discharge, healing was nearly complete, and he was again infused with Infliximab. 4.5 months after discharge, his lesions had completely healed, albeit with significant scarring. Conclusions: To our knowledge, less than 10 cases of pediatric bullous pyoderma gangrenosum have been reported. Additionally, we are not aware of any other reported cases of bullous PG occurring in a Native American child. PG is often associated with systemic diseases such as inflammatory bowel disease, and hematologic malignancy but no underlying systemic condition was ever found in the current case. As shown in this case, PG is often mistaken for infection, which can delay diagnosis and increase long term morbidity.