Bone Metabolism after Total Hip Revision Surgery with Impacted Grafting: Evaluation using H215O and [18F]fluoride PET; A Pilot Study

Purpose: To evaluate bone blood flow and bone formation in patients after total hip revision surgery with impacted bone grafting using H2 15O and [18F]fluoride positron emission tomography (PET). Procedures: To asses bone blood flow and bone metabolism in bone allograft after impaction grafting, four patients treated with total hip revision surgery were enrolled prospectively in this study. Six patients scheduled for primary hip arthroplasties were included as a control group. The study protocol consisted of three H2 15O and [18F]fluoride PET scans in each patient. Results: Bone blood flow increased significantly compared to the preoperative state in patients treated for primary hip arthroplasty. In patients undergoing revision surgery, bone blood flow was twofold to threefold higher compared to the preoperative state, but did not reach significance. Bone metabolism in patients undergoing revision was threefold higher 2 weeks postoperatively compared to the primary hip group. We found a significant correlation between Ki and bone blood flow. Conclusions: Allogeneic bone grafts induce a higher rate of local periprosthetic bone formation compared to periprosthetic bone formation after a primary total hip placement. In vivo coupling between bone blood flow and bone metabolism suggests that bone metabolism in allogeneic bone grafts may partly rely on bone blood flow adaptations

Attenuation-Corrected vs. Nonattenuation-Corrected 2-Deoxy-2-[F-18]fluoro-d-glucose-Positron Emission Tomography in Oncology, A Systematic Review

Purpose: To perform a systematic review and meta-analysis to determine the diagnostic accuracy of attenuation-corrected (AC) vs. nonattenuation-corrected (NAC) 2-deoxy-2-[F-18] fluoro-D-glucose-positron emission tomography (FDG-PET) in oncological patients. Procedures: Following a comprehensive search of the literature, two reviewers independently assessed the methodological quality of eligible studies. The diagnostic value of AC was studied through its sensitivity/specificity compared to histology, and by comparing the relative lesion detection rate reported with NAC-PET vs. AC, for full-ring and dual-head coincidence PET (FRand DH-PET, respectively). Results: Twelve studies were included. For FR-PET, the pooled sensitivity/specificity on a patient basis was 64/97 % for AC and 62/99 % for NAC, respectively. Pooled lesion detection with NAC vs. AC was 98 % [95 % confidence interval (95 % CI): 96Y99%, n=1,012 lesions] for FR-PET, and 88 % (95 % CI:81Y94%, n=288 lesions) for DH-PET. Conclusions: Findings suggest similar sensitivity/specificity and lesion detection for NAC vs. AC FR-PET and significantly higher lesion detection for NAC vs. AC DH-PET

Reversal Of Arterial Disease by modulating Magnesium and Phosphate (ROADMAP-study):rationale and design of a randomized controlled trial assessing the effects of magnesium citrate supplementation and phosphate-binding therapy on arterial stiffness in moderate chronic kidney disease

Background: Arterial stiffness and calcification propensity are associated with high cardiovascular risk and increased mortality in chronic kidney disease (CKD). Both magnesium and phosphate are recognized as modulators of vascular calcification and chronic inflammation, both features of CKD that contribute to arterial stiffness. In this paper, we outline the rationale and design of a randomized controlled trial (RCT) investigating whether 24 weeks of oral magnesium supplementation with or without additional phosphate-binding therapy can improve arterial stiffness and calcification propensity in patients with stage 3-4 CKD. Methods: In this multi-center, placebo-controlled RCT, a total of 180 participants with an estimated glomerular filtration rate of 15 to 50 ml/min/1.73 m(2) without phosphate binder therapy will be recruited. During the 24 weeks intervention, participants will be randomized to one of four intervention groups to receive either magnesium citrate (350 mg elemental magnesium/day) or placebo, with or without the addition of the phosphate binder sucroferric oxyhydroxide (1000 mg/day). Primary outcome of the study is the change of arterial stiffness measured by the carotid-femoral pulse wave velocity over 24 weeks. Secondary outcomes include markers of calcification and inflammation, among others calcification propensity (T-50) and high-sensitivity C-reactive protein. As explorative endpoints, repeated F-18-FDG and F-18-NaF PET-scans will be performed in a subset of participants (n = 40). Measurements of primary and secondary endpoints are performed at baseline, 12 and 24 weeks. Discussion: The combined intervention of magnesium citrate supplementation and phosphate-lowering therapy with sucroferric oxyhydroxide, in stage 3-4 CKD patients without overt hyperphosphatemia, aims to modulate the complex and deregulated mineral metabolism leading to vascular calcification and arterial stiffness and to establish to what extent this is mediated by T(50 )changes. The results of this combined intervention may contribute to future early interventions for CKD patients to reduce the risk of CVD and mortality

When Limb Surgery Has Become the Only Life-Saving Therapy in FOP: A Case Report and Systematic Review of the Literature

Fibrodysplasia ossificans progressiva (FOP) is a rare disease in which heterotopic ossification (HO) is formed in muscles, tendons and ligaments. Traumatic events, including surgery, are discouraged as this is known to trigger a flare-up with risk of subsequent HO. Anesthetic management for patients with FOP is challenging. Cervical spine fusion, ankylosis of the temporomandibular joints, thoracic insufficiency syndrome, restrictive chest wall disease, and sensitivity to oral trauma complicate airway management and anesthesia and pose life-threatening risks. We report a patient with FOP suffering from life-threatening antibiotic resistant bacterial infected ulcers of the right lower leg and foot. The anesthetic, surgical and postoperative challenges and considerations are discussed. In addition, the literature on limb surgeries of FOP patients is systemically reviewed. The 44 year-old female patient was scheduled for a through-knee amputation. Airway and pulmonary evaluation elicited severe abnormalities, rendering standard general anesthesia a rather complication-prone approach in this patient. Thus, regional anesthesia, supplemented with intravenous analgosedation and N2O-inhalation were performed in this case. The surgery itself was securely planned to avoid any unnecessary tissue damage. Postoperatively the patient was closely monitored for FOP activity by ultrasound and [18F]PET/CT-scan. One year after surgery, a non-significant amount of HO had formed at the operated site. The systematic review revealed seventeen articles in which thirty-two limb surgeries in FOP patients were described. HO reoccurrence was described in 90% of the cases. Clinical improvement due to improved mobility of the operated joint was noted in 16% of the cases. It should be noted, though, that follow-up time was limited and no or inadequate imaging modalities were used to follow-up in the majority of these cases. To conclude, if medically urgent, limb surgery in FOP is possible even when general anesthesia is not preferred. The procedure should be well-planned, alternative techniques or procedures should be tested prior to surgery and special attention should be paid to the correct positioning of the patient. According to the literature recurrent HO should be expected after surgery of a limb, even though it was limited in the case described