Assessing tophaceous spinal gout treatment response using dual-energy CT as a point-of-care imaging modality: case report.

We describe a case of chronic tophaceous gout affecting the spine, hands, elbows, feet, and knees in a 67-year-old man with serum urate levels at 549 µmol/L whose response to treatment was successfully mapped using dual-energy computed tomography (DECT). The patient presented with exacerbation of acute-on-chronic lumbar back pain. He had received a diagnosis of gout 3 years prior to this presentation yet was not on any urate-lowering therapy. The patient received febuxostat 80 mg and colchicine 0.3 mg once daily and underwent DECT to assess baseline monosodium urate (MSU) burden. At baseline, MSU deposits were seen in the hands, elbows, feet, knees, and lumbar spine including the left L5-S1 facet joint encroaching onto the neural foramen. After 2.5 years of treatment, serum urate level was within the target range (< 360 µmol/L), and the patient underwent a follow-up DECT that revealed almost full resolution of MSU deposition in the spine, including the MSU-burdened facet joint and neural foramen in the lumbar spine, in addition to all the affected peripheral joints. This case is the first report of radiological evidence of nearly complete resolution of MSU deposits in spinal gout on DECT after urate-lowering therapy treatment, which demonstrates the utility of this imaging modality as a non-invasive investigational point-of-care imaging modality for mapping treatment response and identifying the etiology of back pain in a patient with chronic tophaceous spinal gout.

The uncrossed-doubled patellar tendon: A novel imaging finding.

A spectrum of anatomic variants of the conventional single patellar tendon have been described however a double patellar tendon is a highly rare finding, which has only been described once before where a cross-over tendon morphology was illustrated. We report the case of a 46-year-old man with a 3 month history of left knee pain who was found to have an incidental double patellar tendon without cross-over, with one deep bundle demonstrating a more conventional patellar tendon course, paralleled by a second anatomically-distinct superficial bundle of differing morphology coursing anterolateral to the deep conventional bundle, explicitly connecting patella to tibial tuberosity. A comprehensive understanding of the anatomic variations of the patellar tendon is essential for both radiologist and clinician to deliver safe clinical practice. We present a rare case of an uncrossed-doubled patellar tendon, which to our knowledge, has never been reported.

Intra-operative fluoroscopic radiation exposure in orthopaedic trauma theatre.

INTRODUCTION: Radiation exposure from intra-operative fluoroscopy in orthopaedic trauma surgery is a common occupational hazard. References for fluoroscopy use in the operating room for commonly performed operations have not been reported adequately. This study aimed to report appropriate intra-operative fluoroscopy use in orthopaedic trauma and compare the effect of surgery type and surgeon grade on radiation exposure. METHODS: Data on 849 cases over an 18-month period were analysed retrospectively. Median and 75th centile values for dose area product (DAP), screening time (ST), and number of fluoroscopy images were calculated for procedures where n > 9 (n = 808). RESULTS: Median DAP for dynamic hip screws for extracapsular femoral neck fractures was 668 mGy/cm2 (ST 36 s), 1040 mGy/cm2 (ST 49 s) for short proximal femoral nail, 1720 mGy/cm2 (ST 2 m 36 s) for long femoral nail for diaphyseal fractures, 25 mGy/cm2 (ST 25 s) for manipulation and Kirschner wire fixation in distal radius fractures, and 27 mGy/cm2 (ST 23 s) for volar locking plate fixation in distal radius fractures. These represented the five commonest procedures performed in the trauma operating room in our hospital. Experienced surgeons utilized less radiation in the operating room than junior surgeons (DAP 90.55 vs. 366.5 mGy/cm2, p = 0.001) and took fewer fluoroscopic images (49 vs. 66, p = 0.008) overall. CONCLUSIONS: This study reports reference values for common trauma operations. These can be utilized by surgeons in the operating room to raise awareness and perform clinical audits of appropriate fluoroscopy use for orthopaedic trauma, using this study as guidance for standards. We demonstrated a significant reduction in fluoroscopy usage with increasing surgeon experience.

Physiological role for nitrate-reducing oral bacteria in blood pressure control.

Circulating nitrate (NO(3)(-)), derived from dietary sources or endogenous nitric oxide production, is extracted from blood by the salivary glands, accumulates in saliva, and is then reduced to nitrite (NO(2)(-)) by the oral microflora. This process has historically been viewed as harmful, because nitrite can promote formation of potentially carcinogenic N-nitrosamines. More recent research, however, suggests that nitrite can also serve as a precursor for systemic generation of vasodilatory nitric oxide, and exogenous administration of nitrate reduces blood pressure in humans. However, whether oral nitrate-reducing bacteria participate in "setting" blood pressure is unknown. We investigated whether suppression of the oral microflora affects systemic nitrite levels and hence blood pressure in healthy individuals. We measured blood pressure (clinic, home, and 24-h ambulatory) in 19 healthy volunteers during an initial 7-day control period followed by a 7-day treatment period with a chlorhexidine-based antiseptic mouthwash. Oral nitrate-reducing capacity and nitrite levels were measured after each study period. Antiseptic mouthwash treatment reduced oral nitrite production by 90% (p < 0.001) and plasma nitrite levels by 25% (p = 0.001) compared to the control period. Systolic and diastolic blood pressure increased by 2-3 .5mmHg, increases correlated to a decrease in circulating nitrite concentrations (r(2) = 0.56, p = 0.002). The blood pressure effect appeared within 1 day of disruption of the oral microflora and was sustained during the 7-day mouthwash intervention. These results suggest that the recycling of endogenous nitrate by oral bacteria plays an important role in determination of plasma nitrite levels and thereby in the physiological control of blood pressure.