High resolution ultrasound for the evaluation of radial nerve pathology adjacent to metallic hardware.

Accurate localization and characterization of peripheral nerve injuries adjacent to metallic hardware is difficult with magnetic resonance imaging (MRI) due to susceptibility artifact. This study sought to present the use of high-resolution ultrasound (US) in accurate characterization of radial nerve injury adjacent to metallic hardware, using findings at the time of operative exploration as confirmation of the US assessment. A retrospective chart review of cases with clinically identified radial nerve injuries evaluated by the high-resolution US was performed from January 2015 through December 2019. Preoperative clinical data, US reports, MRI reports, electrodiagnostic (EDx) reports, and operative reports were reviewed for each case. Preoperative US correctly characterized the affected nerve component, type, and location of injury in all 13 cases (100%), when correlated with intraoperative findings. Nerve injury was directly adjacent to metallic hardware in 12 cases (92%). Out of the seven cases evaluated by both US and MRI, US correctly accurately diagnosed radial nerve injuries in all cases, whereas MRI accurately diagnosed in four cases (57%). In 3/7 cases (43%) MRI was nondiagnostic due to susceptibility artifact. MRI evaluation of the nerve was limited to some degree by metallic artifact in 6/7 cases (85%).

Management of acute injuries of the tibiofibular syndesmosis.

The syndesmosis is important for ankle stability and load transmission and is commonly injured in association with ankle sprains and fractures. Syndesmotic disruption is associated with between 5 and 10% of ankle sprains and 11-20% of operative ankle fractures. Failure to recognize and appropriately treat syndesmotic disruption can portend poor functional outcomes for patients; therefore, early recognition and appropriate treatment are critical. Syndesmotic injuries are difficult to diagnose, and even when identified and treated, a slightly malreduced syndesmosis can lead to joint destruction and poor functional outcomes. This review will discuss the relevant anatomy, biomechanics, mechanism of injury, clinical evaluation, and treatment of acute injuries to the ankle syndesmosis.

L5-S1 Achromobacter xylosoxidans infection secondary to oxygen-ozone therapy for the treatment of lumbosacral disc herniation: a case report and review of the literature.

STUDY DESIGN: Case report and literature review. OBJECTIVE: To present a unique case of Achromobacter xylosoxidans infection secondary to oxygen-ozone therapy for the treatment of L5-S1 disc herniation. SUMMARY OF BACKGROUND DATA: Oxygen-ozone therapy is a minimally invasive technique for the treatment of lumbar disc herniations, with unproven efficacy and few reported complications. Achromobacter xylosoxidans is an opportunistic pathogen that inhabits aquatic environments and is a rare cause of osteomyelitis. To the best of our knowledge, this is the first report of A. xylosoxidans spondylodiscitis in the lumbar spine and the third report of spinal infection after intradiscal oxygen-ozone chemonucleolysis in the English literature. METHODS: The medical records, operative reports, and radiographical imaging studies of a single patient were retrospectively reviewed. RESULTS: A 29-year-old female patient who previously underwent oxygen-ozone therapy for L5-S1 disc herniation presented to our institution with a 5-month history of intractable back and leg pain. The patient's laboratory studies were within normal limits and did not indicate signs of an active infection. Her physical examination revealed globally decreased muscle strength (4/5) and hyperesthesia in the lower extremities. Magnetic resonance imaging and computed tomography revealed severe disc degeneration and vertebral body endplate changes at L5-S1, in addition to paravertebral soft tissue swelling consistent with a previous infection. Given the severity of symptoms, the patient underwent anterior lumbar interbody fusion and posterior segmental instrumentation at L5-S1. Histopathological evaluation of the disc material confirmed the diagnosis of chronic osteomyelitis and septic discitis at L5-S1. Intraoperative cultures grew A. xylosoxidans and Propionibacterium acnes. The patient had prompt improvement in her level of pain and was discharged on a 6-week course of piperacillin-tazobactam without complication. CONCLUSION: This first report of A. xylosoxidans vertebral infection secondary to oxygen-ozone therapy illustrates the wide variety of environmental pathogens that can complicate the percutaneous treatment of degenerative vertebral disease.

TAT-mediated transduction of MafA protein in utero results in enhanced pancreatic insulin expression and changes in islet morphology.

Alongside Pdx1 and Beta2/NeuroD, the transcription factor MafA has been shown to be instrumental in the maintenance of the beta cell phenotype. Indeed, a combination of MafA, Pdx1 and Ngn3 (an upstream regulator of Beta2/NeuroD) was recently reported to lead to the effective reprogramming of acinar cells into insulin-producing beta cells. These experiments set the stage for the development of new strategies to address the impairment of glycemic control in diabetic patients. However, the clinical applicability of reprogramming in this context is deemed to be poor due to the need to use viral vehicles for the delivery of the above factors. Here we describe a recombinant transducible version of the MafA protein (TAT-MafA) that penetrates across cell membranes with an efficiency of 100% and binds to the insulin promoter in vitro. When injected in utero into living mouse embryos, TAT-MafA significantly up-regulates target genes and induces enhanced insulin production as well as cytoarchitectural changes consistent with faster islet maturation. As the latest addition to our armamentarium of transducible proteins (which already includes Pdx1 and Ngn3), the purification and characterization of a functional TAT-MafA protein opens the door to prospective therapeutic uses that circumvent the use of viral delivery. To our knowledge, this is also the first report on the use of protein transduction in utero.