Factors influencing providers' decisions on management of bone health in people with spinal cord injury.

STUDY DESIGN: Survey. OBJECTIVES: Managing osteoporosis in persons with chronic spinal cord injury (SCI) is difficult as little evidence exists regarding effective strategies. We examined the effect of key factors on providers' bone health management decisions in persons with SCI. SETTING: USA. METHODS: Providers reviewed blocks of 9 hypothetical cases that varied on four factors: osteoporosis, osteopenia, or normal bone mineral density using dual-energy X-ray absorptiometry (DXA); DXA region of interest (lumbar spine, hip, knee), prior lower extremity fracture; and no or limited ambulation. They indicated how likely they would recommend pharmacological management, what treatment(s) they would recommend, and whether they would request another DXA before treatment. RESULTS: Eighty-two healthcare providers completed the survey. Treatment recommendations for bisphosphonates and Vitamin D/calcium supplements, respectively, were more likely if there was a prior fracture (OR: 2.65, 95%CI: 1.76-3.99, p < 0.0001; OR: 2.96, 95%CI: 1.40-6.26, p = 0.004) and if a DXA scan found osteopenia (OR: 2.23, 95%CI: 1.41-3.54, p = 0.001; OR: 6.56, 95%CI: 2.71-15.85, p < 0.0001) or osteoporosis (OR: 12.08, 95%CI: 7.09-20.57, p < 0.0001; OR: 4.54, 95%CI: 2.08-9.90, p < 0.0001). Another DXA scan was more likely to be requested if there was a prior fracture (OR: 1.75, 95%CI: 1.10-2.78, p = 0.02) but less likely if the person was nonambulatory (OR: 0.41, 95%: 0.19-0.90, p = 0.03). CONCLUSIONS: Prior fracture and DXA findings influenced treatment recommendations for bone health management in SCI. Reliance on lumbar spine scans to determine bone loss and treatment identifies a knowledge gap for which future education is required.

Effect of platform switching on peri-implant bone: A 3D finite element analysis.

STATEMENT OF PROBLEM: A consensus regarding the effects of platform switching on peri-implant marginal bone levels is lacking. Finite element studies have reported contradictory results. PURPOSE: The purpose of this finite element analysis study was to evaluate stress distribution in platform-switched (PS) and platform-matched (PM) implants and their surrounding bone. MATERIAL AND METHODS: An implant (4.5×11 mm) was modeled and screwed into a human mandibular bone block using a computer-aided design (CAD) software program. Two separate models were generated: (1) PM, 4.5-mm implant with 4.5-mm-wide abutment and (2) PS, 4.5-mm implant with 3.5-mm-wide abutment. Implant components were modeled with linear isotropic properties and bones with anisotropic properties. Vertical (200 to 800 N) and oblique (50 to 150 N) forces were applied to each model to simulate occlusal loads. Linear elastic analysis was performed using ANSYS Workbench 16. von Mises equivalent stresses in the implant assemblies and peri-implant bone were calculated and compared with independent samples t test (α=.05). RESULTS: von Mises equivalent stress values under simulated axial and nonaxial occlusal loads were lower for PM than for PS implant assemblies. However, the differences were not statistically significant. Stress within the peri-implant bone was significantly higher for the PM group than for the PS group (P<.001). CONCLUSIONS: Platform switching decreased stress within peri-implant bone and may help limit marginal bone resorption.

Electron-induced dissociation of glycosaminoglycan tetrasaccharides.

Electron detachment dissociation (EDD) Fourier transform mass spectrometry has recently been shown to be a powerful tool for examining the structural features of sulfated glycosaminoglycans (GAGs). The characteristics of GAG fragmentation by EDD include abundant cross-ring fragmentation primarily on hexuronic acid residues, cleavage of all glycosidic bonds, and the formation of even- and odd-electron product ions. GAG dissociation by EDD has been proposed to occur through the formation of an excited species that can undergo direct decomposition or ejects an electron and then undergoes dissociation. In this work, we perform electron-induced dissociation (EID) on singly charged GAGs to identify products that form via direct decomposition by eliminating the pathway of electron detachment. EID of GAG tetrasaccharides produces cleavage of all glycosidic bonds and abundant cross-ring fragmentation primarily on hexuronic acid residues, producing fragmentation similar to EDD of the same molecules, but distinctly different from the products of infrared multiphoton dissociation or collisionally activated decomposition. These results suggest that observed abundant fragmentation of hexuronic acid residues occurs as a result of their increased lability when they undergo electronic excitation. EID fragmentation of GAG tetrasaccharides results in both even- and odd-electron products. EID of heparan sulfate tetrasaccharide epimers produces identical fragmentation, in contrast to EDD, in which the epimers can be distinguished by their fragment ions. These data suggest that for EDD, electron detachment plays a significant role in distinguishing glucuronic acid from iduronic acid.

Evaluation of a ketogenic diet for improvement of neurological recovery in individuals with acute spinal cord injury: a pilot, randomized safety and feasibility trial.

STUDY DESIGN: Longitudinal, randomized study. OBJECTIVES: (1) Test the safety and feasibility of a ketogenic diet (KD) intervention in the acute stages of spinal cord injury (SCI), (2) assess the effects of a KD on neurological recovery, and (3) identify potential serum biomarkers associated with KD-induced changes in neurological recovery. SETTING: Acute care and rehabilitation facility. METHODS: The KD is a high-fat, low-carbohydrate diet that includes ≈70-80% total energy as fat. Seven participants with acute complete and incomplete SCI (AIS A-D) were randomly assigned to KD (n = 4) or standard diet (SD, n = 3). Neurological examinations, resting energy expenditure analysis, and collection of blood for evaluation of circulating ketone levels were performed within 72 h of injury and before discharge. Untargeted metabolomics analysis was performed on serum samples to identify potential serum biomarkers that may explain differential responses between groups. RESULTS: Our pilot findings primarily demonstrated that KD is safe and feasible to be administered in acute SCI. Furthermore, upper extremity motor scores were higher (p < 0.05) in the KD vs. SD group and an anti-inflammatory lysophospholipid, lysoPC 16:0, was present at higher levels, and an inflammatory blood protein, fibrinogen, was present at lower levels in the KD serum samples vs. SD serum samples. CONCLUSION: Taken together, these preliminary results suggest that a KD may have anti-inflammatory effects that may promote neuroprotection, resulting in improved neurological recovery in SCI. Future studies with larger sample size are warranted for demonstrating efficacy of KD for improving neurological recovery.

Pulse article: How do you do the international standards for neurological classification of SCI anorectal exam?

STUDY DESIGN: Online survey of spinal cord injury (SCI) practitioners. OBJECTIVES: Determine provider understanding and routine performance of International Standards for Neurologic Classification of Spinal Cord Injury (ISNCSCI) anorectal examination. SETTING: International online questionnaire. METHODS: A descriptive survey was developed to assess current performance of the ISNCSCI anorectal exam. Information about this survey was disseminated through social email and international societies between the months of March and April 2017. RESULTS: Two hundred and fifteen SCI practitioners completed the survey. Of these, 157 (73%) were specialists in physical medicine and rehabilitation, 32 (15%) were physical therapists, 6 were neurologists, 6 were orthopedists, and 3 were neurosurgeons. Of responders, 90% routinely personally performed the anal exam of the ISNCSCI, of whom, 42 placed firm pressure against the anal sphincter, 58 placed firm pressure against the rectal wall, and 87 placed firm pressure against the anal sphincter and rectal wall as part of the exam. On a routine basis, 74% tested sensation at the junction of the anal sphincter and skin, 82% had the patient attempt to squeeze their finger, and 50% performed the bulbocavernosus reflex. CONCLUSIONS: Marked inconsistency exists in the performance of the ISNCSCI anal examination. Researchers and clinicians need more education about the performance of the examination. Consideration should be given for the components of deep rectal sensation and anal pressure to be separately documented in the neurologic exam and for researchers to focus separately on recovery of sacral function vs. ambulatory function in clinical trials.

A historical study of appendicular fractures in veterans with traumatic chronic spinal cord injury: 2002-2007.

OBJECTIVE: Describe the incidence and distribution of appendicular fractures in a cohort of veterans with spinal cord injury (SCI). DESIGN: Retrospective, observational study of fractures in veterans with a chronic traumatic SCI. SETTING: The Veterans Health Administration (VA) healthcare system. PARTICIPANTS: Veterans included in the VA Spinal Cord Dysfunction Registry from Fiscal Years (FY) FY2002-FY2007. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Description of fractures by site and number. Mortality at one year following incident fracture among men with single vs. multiple fractures. RESULTS: Male and female veterans sustained incident fractures with similar observed frequency (10.5% vs 11.5%). The majority of fractures occurred in the lower extremities for both men and women. In men, a complete extent of injury (compared to incomplete) was associated with 41% greater relative risk (RR) of incident fracture (RR 1.41, 95% confidence interval [1.17, 1.70]) among those with tetraplegia, but not paraplegia. Furthermore, many men (33.9%, n = 434) sustained multiple fractures over the course of the study. There were no differences in mortality between men who sustained a single fracture and those who had multiple fractures. CONCLUSIONS: The extent of injury may be an important predictor of fracture risk for male veterans with tetraplegia. Once a fracture occurs, male veterans with SCI appear to be at high risk for additional fractures.