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Background and Objectives: Spinal fusion is an effective and widely accepted intervention. However, complications such as non-unions and hardware failures are frequently observed. Radiologic imaging and physical examination are still the gold standards in the assessment of spinal fusion, despite multiple limitations including radiation exposure and subjective image interpretation. Furthermore, current diagnostic methods only allow fusion assessment at certain time points and require the patient’s presence at the hospital or medical practice. A recently introduced implantable sensor system for continuous and wireless implant load monitoring in trauma applications carries the potential to overcome these drawbacks, but transferability of the principle to the spine has not been demonstrated yet. Materials and Methods: The existing trauma sensor was modified for attachment to a standard pedicle-screw-rod system. Two lumbar segments (L2 to L4) of one Swiss white alpine sheep were asymmetrically instrumented. After facetectomy, three sensors were attached to the rods between each screw pair and activated for measurement. The sheep was euthanized 16 weeks postoperatively. After radiological assessment the spine was explanted and loaded in flexion-extension to determine the range of motion of the spinal segments. Sensor data were compared with mechanical test results and radiologic findings. Results: The sensors measured physiological rod loading autonomously over the observation period and delivered the data daily to bonded smartphones. At euthanasia the relative rod load dropped to 67% of the respective maximum value for the L23 segment and to 30% for the L34 segment. In agreement, the total range of motion of both operated segments was lower compared to an intact reference segment (L23: 0.57°; L34: 0.49°; intact L45: 4.17°). Radiologic assessment revealed fusion mass in the facet joint gaps and bilateral bridging bone around the joints at both operated segments. Conclusions: Observations of this single-case study confirm the basic ability of continuous rod load measurement to resolve the spinal fusion process as indicated by a declining rod load with progressing bone fusion. A strong clinical potential of such technology is eminent, but further data must be collected for final proof of principle.

Background: Surgical treatment for erosive pyogenic spondylodiscitis of the lumbar spine is challenging as, following debridement of the intervertebral and bony abscess, a large and irregular defect is created. Sufficient defect reconstruction with conventional implants using a posterior approach is often impossible. Therefore, we developed the “Cement-PLIF”, a single-stage posterior lumbar procedure, combining posterior lumbar interbody fusion (PLIF) with defect-filling using antibiotic-loaded polymethylmethacrylate (PMMA). This study first describes and evaluates the procedure’s efficacy, safety, and infection eradication rate. Radiological implant stability, bone-regeneration, sagittal profile reconstruction, procedure-related complications, and pre-existing comorbidities were further analyzed. Methods: A retrospective cohort study analyzing 73 consecutive patients with a minimum of a one-year follow-up from 2000–2017. Patient-reported pain levels and improvement in infectious serological parameters evaluated the clinical outcome. Sagittal profile reconstruction, anterior bone-regeneration, and posterior fusion were analyzed in a.p. and lateral radiographs. A Kaplan–Meier analysis was used to determine the impact of pre-existing comorbidities on mortality. Pre-existing comorbidities were quantified using the Charlson-Comorbidity Index (CCI). Results: Mean follow-up was 3.3 (range: 1–16; ±3.2) years. There was no evidence of infection persistence in all patients at the one-year follow-up. One patient underwent revision surgery for early local infection recurrence (1.4%). Five (6.9%) patients required an early secondary intervention at the same level due to minor complications. Radiological follow-up revealed implant stability in 70/73 (95.9%) cases. Successful sagittal reconstruction was demonstrated in all patients (p < 0.001). There was a significant correlation between Kaplan–Meier survival and the number of pre-existing comorbidities (24-months-survival: CCI ≤ 3: 100%; CCI ≥ 3: 84.6%; p = 0.005). Conclusions: The Cement-PLIF procedure for pyogenic erosive spondylodiscitis is an effective and safe treatment as evaluated by infection elimination, clinical outcome, restoration, and maintenance of stability and sagittal alignment.

In vitro and in vivo studies evidenced that mesenchymal stem cells (MSCs) contribute to intervertebral disc (IVD) regeneration by differentiation towards the disc phenotype and matrix synthesis and/or by paracrine signalling to endogenous cells, thereby promoting a healthier disc phenotype in degenerative discs. The aim of this study was to investigate IVD response to human MSC (hMSC) treatment based on the disc degenerative state and hMSC carrier. Bovine caudal IVDs with endplates were cultured in a bioreactor under simulated physiological (0.1 Hz load and sufficient glucose) or degenerative (10 Hz load and limited glucose) conditions for 7 days. Discs were partially nucleotomised, restored with hMSCs in either fibrin gel or saline solution and cultured under physiological conditions for 7 days. Controls included fibrin and saline without hMSCs. Cell viability, histology, disc height, and gene expression analyses were performed to evaluate regeneration. hMSCs in fibrin were viable and homogenously distributed following 7 days of culture under dynamic loading in partially nucleotomised discs. IVD response to hMSCs was conditioned by both disc degenerative state and hMSC carrier. The effect of the regenerative treatment was stronger on simulated-degenerative discs than on simulated-physiological discs. hMSCs in fibrin induced a superior anabolic response in degenerative IVDs compared with fibrin alone, thus suggesting an added value of the cellular therapy compared with an acellular solution. When comparing fibrin and saline as a hMSC carrier, a significantly higher anabolic response was observed in IVDs treated with hMSCs in fibrin. Moreover, it was found that the degenerative state of the disc influenced hMSC differentiation. Indeed, a significantly higher expression of specific discogenic markers (ACAN and CA12) was observed in hMSCs implanted into physiological discs than in those implanted into degenerative discs. In conclusion, host disc cells and donor hMSC response depend on the degenerative state of the host disc and carrier used for hMSC delivery, and these two aspects need to be considered for a successful translation of hMSC therapies for the treatment of IVD degeneration.

There is variability in practice among care providers on feeding infants admitted with neonatal hypoglycemia (NH) for parenteral dextrose. We compared clinical outcomes in infants who were fed (NH-Fed) and hypoglycemic infants who were kept nothing per os (NPO) (NH-NPO) at the time of initiation of intravenous (IV) dextrose. We performed a retrospective review of all newborn infants admitted to the neonatal intensive care unit with NH for IV dextrose. Infants were grouped as per the feeding approach at initiation of IV dextrose: NH-Fed or NH-NPO infants. We found that infants in the NH-Fed group had lower maximum glucose infusion rate, less duration of glucose infusion therapy compared with the NH-NPO group, and significantly less number of days of hospital stay compared with the NH-NPO group (5.87 ± 1.4 days vs 4.9 ± 1.4 days, P < .006). In conclusion, feeding infants with hypoglycemia who require IV dextrose offers tangible benefits of shorter duration of parenteral dextrose and shorter length of hospitalization.

Background: The Medical Student Performance Evaluation (MSPE) is a primary source of information used by residency programs in their selection of trainees. The MSPE contains a narrative description of the applicant's performance during medical school. In 2002, the Association of American Medical Colleges' guideline for preparation of the MSPE recommended inclusion of a comparative summative assessment of the student's overall performance relative to his/her peers (final adjective)., Objective: We hypothesize that the inclusion of a final adjective in the MSPE affects a reviewer's assessment of the applicant's desirability more than the narrative description of performance and designed a study to evaluate this hypothesis., Design: Fifty-six faculty members from the Departments of Pediatrics and Medicine with experience reviewing MSPEs as part of the intern selection process reviewed two pairs of mock MSPE letters. In each pair, the narrative in one letter was superior to that in the other. Two final adjectives describing relative class ranks were created. Each subject was first presented with a pair of letters with mismatched final adjective (study), i.e., the letter with the stronger narrative was presented with the weaker final adjective and vice versa. The subject was then presented with a second pair of letters without final adjectives (control). Subjects ranked the relative desirability of the two applicants in each pair., Results: The proportion of rankings congruent with the strength of the narratives under study and control conditions were compared. Subjects were significantly less likely to rank the applicants congruent with the strength of the narratives when the strength of the final adjectives conflicted with the strength of the narrative; 42.9% of study letters were ranked congruent with the narrative versus 82.1% of controls (p = 0.0001)., Conclusion: The MSPE final adjective had a greater impact than the narrative description of performance on the determination of applicant desirability., Abbreviations: MSPE: Medical Student Performance Evaluation; AAMC: Association of American Medical Colleges; BCM: Baylor College of Medicine.

Background: While much is known about how educational leaders at the medical school level (eg, deans) view the importance of formal training in education for medical school teachers, little is known about how leaders at the clinical level (eg, department chairs) view such training. We sought to determine how pediatric department chairs and residency program directors view the value of formal training in education, such as that at a Master of Education (MEd) level, and to estimate the number of clinical pediatric faculty with or pursuing such training., Methods: A survey designed to assess the value placed on formal training in education and to estimate the number of clinical faculty with or pursuing such training was mailed to pediatric department chair persons and residency program directors at all 131 allopathic medical schools in the United States and Puerto Rico., Results: Eighty department chairs (61%) responded, and most indicated that when hiring new faculty, they view an applicant with an MEd as having an advantage. Both chairs and residency directors considered an MEd to be advantageous for a residency director by a ranking of 4.5 and 4.2, respectively, on a scale of 1 to 5 (P  =  .008). Of the 80 chairs who responded, 58.8% of respondents reported one or more faculty in their department had or was pursuing an MEd. Of the 72 responding residency directors (55%), 11 respondents (15.3%) indicated that they had an MEd., Conclusion: More than half the medical school pediatric chairs responding to the survey had one or more clinical faculty with or pursuing an MEd in their departments. Survey results indicated that such training is valued by both department chairs and residency directors. Given the time and expense involved in obtaining an MEd, awareness of these data 5 be helpful to those considering pursuing, offering, or requiring such training.

Background: Despite the advent of evidence-based medicine, clinical pearls, verbal and published, remain a popular and important part of medical education., Aims: The purpose of this study was to establish a definition of a clinical pearl and to determine criteria for an educationally sound clinical pearl., Methods: The authors searched the Medline database for material dealing with clinical pearls, examined and discussed the information found, and formulated a consensus opinion regarding the definition and criteria., Results: Clinical pearls are best defined as small bits of free standing, clinically relevant information based on experience or observation. They are part of the vast domain of experience-based medicine, and can be helpful in dealing with clinical problems for which controlled data do not exist., Conclusions: While there are no universally accepted criteria for preparing or evaluating a clinical pearl, we propose some rational guidelines for both.

We determined the frequency and clinical significance of white blood cell (WBC) counts greater than or equal to 25,000/microliters in children presenting to an emergency department (ED) and defined a degree of leukocytosis which might be considered extreme in this setting. Records of all patients seen in the ED between February 1985 and December 1986 with WBC counts greater than or equal to 25,000/microliters were identified. Each patient was paired with the chronologically nearest patient with a WBC count between 15,000 and 25,000/microliters. Of the total WBCs obtained, 5.8% were greater than or equal to 25,000/microliters; only 1% were greater than or equal to 35,000/microliters. Eighteen percent of patients with counts greater than or equal to 25,000/microliters had a serious disease, and 6% had bacteremia. Twenty-six percent of patients with counts greater than or equal to 35,000/microliters had a serious disease, and 10% had bacteremia. On the basis of infrequency and severity of illness, we suggest that, in children presenting to a pediatric emergency department, WBC counts greater than or equal to 35,000/microliters be considered extreme leukocytosis.

Occult bacteremia should be of major concern in the child with fever without localizing signs. A number of clinical features and laboratory findings correlate with the risk of bacteremia in such children, and their recognition permits the identification of a group of children at high risk. Treatment of such children with antibiotics on an ambulatory basis appears to significantly lessen the incidence of persistent bacteremia, subsequent meningitis, and other serious localized bacterial infections.

The charts of 104 white and 52 black children with bacteremia caused by Streptococcus pneumoniae or Haemophilus influenzae type b were reviewed to determine each patient's white blood cell (WBC) and absolute polymorphonuclear cell (PMN) counts at the time of presentation to the emergency room. Mean WBC and PMN counts were virtually identical for the racial groups, 18,300 vs. 18,700/microliter and 12,900 vs. 13,000/microliter, respectively. Examination of subgroups of white and black children with or without meningitis or other focal infection also revealed no significant differences between races, although significantly lower mean WBC and PMN counts were found in children with, compared to those without, meningitis regardless of race. As an aid to the identification of children at high risk for S. pneumoniae or H. influenzae type b bacteremia, it appears that WBC and PMN counts may be interpreted without regard to race.

Charts of 182 outpatient children with bacteremia caused by Streptococcus pneumoniae, Haemophilus influenza type b or Neisseria meningitidis were reviewed. Twenty-four patients (13%) were afebrile (temperature less than 37.8 degrees C) at presentation. Five afebrile patients had no history of fever. Four of the five had localizing signs of infection and one appeared toxic. Afebrile patients were not strikingly different from febrile bacteremic patients by any assessments. Bacteremia in children cannot be excluded on the basis of absence of fever by history and examination. Blood cultures should be performed on afebrile children who either have localizing signs of serious bacterial infection or appear toxic.

Quantitative examination of nasal secretion in patients with cystic fibrosis revealed a significantly greater than normal concentration of calcium, a finding in keeping with the hypothesized importance of this ion in the pathophysiology of the disease.

The records of 182 children with bacteremia due to Streptococcus pneumoniae, Haemophilus influenzae type b, or Neisseria meningitidis were reviewed to determine which variables other than the presence or absence of bacteremia might affect patients' white blood cell (WBC) counts. There were no significant or consistent effects of age, sex, race, or duration of illness on WBC counts. Significantly lower mean WBC counts were noted for patients with, versus those without, meningitis and patients with H influenzae type b bacteremia versus those with S pneumoniae bacteremia. As a screening test for bacteremia, the WBC count is less useful in children with either meningitis or infection caused by H influenzae type b than in children with nonmeningeal infections caused by S pneumoniae.