The University of Kansas Health System

BACKGROUND: Transcatheter aortic-valve replacement (TAVR) is an alternative to surgery in patients with severe aortic stenosis who are at increased risk for death from surgery; less is known about TAVR in low-risk patients. METHODS: We performed a randomized noninferiority trial in which TAVR with a self-expanding supraannular bioprosthesis was compared with surgical aortic-valve replacement in patients who had severe aortic stenosis and were at low surgical risk. When 850 patients had reached 12-month follow-up, we analyzed data regarding the primary end point, a composite of death or disabling stroke at 24 months, using Bayesian methods. RESULTS: ). CONCLUSIONS: In patients with severe aortic stenosis who were at low surgical risk, TAVR with a self-expanding supraannular bioprosthesis was noninferior to surgery with respect to the composite end point of death or disabling stroke at 24 months. (Funded by Medtronic; ClinicalTrials.gov number, NCT02701283.).

BACKGROUND: We compared transcatheter aortic-valve replacement (TAVR), using a self-expanding transcatheter aortic-valve bioprosthesis, with surgical aortic-valve replacement in patients with severe aortic stenosis and an increased risk of death during surgery. METHODS: We recruited patients with severe aortic stenosis who were at increased surgical risk as determined by the heart team at each study center. Risk assessment included the Society of Thoracic Surgeons Predictor Risk of Mortality estimate and consideration of other key risk factors. Eligible patients were randomly assigned in a 1:1 ratio to TAVR with the self-expanding transcatheter valve (TAVR group) or to surgical aortic-valve replacement (surgical group). The primary end point was the rate of death from any cause at 1 year, evaluated with the use of both noninferiority and superiority testing. RESULTS: A total of 795 patients underwent randomization at 45 centers in the United States. In the as-treated analysis, the rate of death from any cause at 1 year was significantly lower in the TAVR group than in the surgical group (14.2% vs. 19.1%), with an absolute reduction in risk of 4.9 percentage points (upper boundary of the 95% confidence interval, -0.4; P<0.001 for noninferiority; P = 0.04 for superiority). The results were similar in the intention-to-treat analysis. In a hierarchical testing procedure, TAVR was noninferior with respect to echocardiographic indexes of valve stenosis, functional status, and quality of life. Exploratory analyses suggested a reduction in the rate of major adverse cardiovascular and cerebrovascular events and no increase in the risk of stroke. CONCLUSIONS: In patients with severe aortic stenosis who are at increased surgical risk, TAVR with a self-expanding transcatheter aortic-valve bioprosthesis was associated with a significantly higher rate of survival at 1 year than surgical aortic-valve replacement. (Funded by Medtronic; U.S. CoreValve High Risk Study ClinicalTrials.gov number, NCT01240902.).

PURPOSE: We report a multicenter, double-blind, randomized trial of bilateral stimulation of the anterior nuclei of the thalamus for localization-related epilepsy. METHODS: Participants were adults with medically refractory partial seizures, including secondarily generalized seizures. Half received stimulation and half no stimulation during a 3-month blinded phase; then all received unblinded stimulation. RESULTS: One hundred ten participants were randomized. Baseline monthly median seizure frequency was 19.5. In the last month of the blinded phase the stimulated group had a 29% greater reduction in seizures compared with the control group, as estimated by a generalized estimating equations (GEE) model (p = 0.002). Unadjusted median declines at the end of the blinded phase were 14.5% in the control group and 40.4% in the stimulated group. Complex partial and "most severe" seizures were significantly reduced by stimulation. By 2 years, there was a 56% median percent reduction in seizure frequency; 54% of patients had a seizure reduction of at least 50%, and 14 patients were seizure-free for at least 6 months. Five deaths occurred and none were from implantation or stimulation. No participant had symptomatic hemorrhage or brain infection. Two participants had acute, transient stimulation-associated seizures. Cognition and mood showed no group differences, but participants in the stimulated group were more likely to report depression or memory problems as adverse events. DISCUSSION: Bilateral stimulation of the anterior nuclei of the thalamus reduces seizures. Benefit persisted for 2 years of study. Complication rates were modest. Deep brain stimulation of the anterior thalamus is useful for some people with medically refractory partial and secondarily generalized seizures.

BACKGROUND: Pain is an enormous problem globally. Estimates suggest that 20% of adults suffer from pain globally and 10% are newly diagnosed with chronic pain each year. Nevertheless, the problem of pain has primarily been regarded as a medical problem, and has been little addressed by the field of public health. DISCUSSION: Despite the ubiquity of pain, whether acute, chronic or intermittent, public health scholars and practitioners have not addressed this issue as a public health problem. The importance of viewing pain through a public health lens allows one to understand pain as a multifaceted, interdisciplinary problem for which many of the causes are the social determinants of health. Addressing pain as a global public health issue will also aid in priority setting and formulating public health policy to address this problem, which, like most other chronic non-communicable diseases, is growing both in absolute numbers and in its inequitable distribution across the globe. SUMMARY: The prevalence, incidence, and vast social and health consequences of global pain requires that the public health community give due attention to this issue. Doing so will mean that health care providers and public health professionals will have a more comprehensive understanding of pain and the appropriate public health and social policy responses to this problem.

BACKGROUND: Whether pembrolizumab given both before surgery (neoadjuvant therapy) and after surgery (adjuvant therapy), as compared with pembrolizumab given as adjuvant therapy alone, would increase event-free survival among patients with resectable stage III or IV melanoma is unknown. METHODS: In a phase 2 trial, we randomly assigned patients with clinically detectable, measurable stage IIIB to IVC melanoma that was amenable to surgical resection to three doses of neoadjuvant pembrolizumab, surgery, and 15 doses of adjuvant pembrolizumab (neoadjuvant-adjuvant group) or to surgery followed by pembrolizumab (200 mg intravenously every 3 weeks for a total of 18 doses) for approximately 1 year or until disease recurred or unacceptable toxic effects developed (adjuvant-only group). The primary end point was event-free survival in the intention-to-treat population. Events were defined as disease progression or toxic effects that precluded surgery; the inability to resect all gross disease; disease progression, surgical complications, or toxic effects of treatment that precluded the initiation of adjuvant therapy within 84 days after surgery; recurrence of melanoma after surgery; or death from any cause. Safety was also evaluated. RESULTS: At a median follow-up of 14.7 months, the neoadjuvant-adjuvant group (154 patients) had significantly longer event-free survival than the adjuvant-only group (159 patients) (P = 0.004 by the log-rank test). In a landmark analysis, event-free survival at 2 years was 72% (95% confidence interval [CI], 64 to 80) in the neoadjuvant-adjuvant group and 49% (95% CI, 41 to 59) in the adjuvant-only group. The percentage of patients with treatment-related adverse events of grades 3 or higher during therapy was 12% in the neoadjuvant-adjuvant group and 14% in the adjuvant-only group. CONCLUSIONS: Among patients with resectable stage III or IV melanoma, event-free survival was significantly longer among those who received pembrolizumab both before and after surgery than among those who received adjuvant pembrolizumab alone. No new toxic effects were identified. (Funded by the National Cancer Institute and Merck Sharp and Dohme; S1801 ClinicalTrials.gov number, NCT03698019.).

BACKGROUND: Atrial fibrillation ablation has made tremendous progress with respect to innovation, efficacy, and safety. However, limited data exist regarding the burden and trends in adverse outcomes arising from this procedure. The aim of our study was to examine the frequency of adverse events attributable to atrial fibrillation (AF) ablation and the influence of operator and hospital volume on outcomes. METHODS AND RESULTS: With the use of the Nationwide Inpatient Sample, we identified AF patients treated with catheter ablation. We investigated common complications including cardiac perforation and tamponade, pneumothorax, stroke, transient ischemic attack, vascular access complications (hemorrhage/hematoma, vascular complications requiring surgical repair, and accidental arterial puncture), and in-hospital death described with AF ablation, and we defined these complications by using validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. An estimated 93,801 AF ablations were performed from 2000 to 2010. The overall frequency of complications was 6.29% with combined cardiac complications (2.54%) being the most frequent. Cardiac complications were followed by vascular complications (1.53%), respiratory complications (1.3%), and neurological complications (1.02%). The in-hospital mortality was 0.46%. Annual operator (<25 procedures) and hospital volume (<50 procedures) were significantly associated with adverse outcomes. There was a small (nonsignificant) rise in overall complication rates. CONCLUSIONS: The overall complication rate was 6.29% in patients undergoing AF ablation. There was a significant association between operator and hospital volume and adverse outcomes. This suggests a need for future research into identifying the safety measures in AF ablations and instituting appropriate interventions to improve overall AF ablation outcomes.

INTRODUCTION: In 2015, the US Alzheimer's Disease Centers (ADC) implemented Version 3 of the Uniform Data Set (UDS). This paper describes the history of Version 3 development and the UDS data that are freely available to researchers. METHODS: UDS Version 3 was developed after years of coordination between the National Institute on Aging-appointed Clinical Task Force (CTF), clinicians from ∼30 ADCs, and the National Alzheimer's Coordinating Center (NACC). The CTF recognized the need for updates to align with the state of the science in dementia research, while being flexible to the diverse needs and diseases studied at the ADCs. Version 3 also developed a nonproprietary neuropsychological battery. RESULTS: This paper focuses on the substantial Version 3 changes to the UDS forms related to clinical diagnosis and characterization of clinical symptoms to match updated consensus-based diagnostic criteria. Between March 2015 and March 2018, 4820 participants were enrolled using UDS Version 3. Longitudinal data were available for 25,337 of the 37,568 total participants using all UDS versions. DISCUSSION: The results from utilization of the UDS highlight the possibility for numerous research institutions to successfully collaborate, produce, and use standardized data collection instruments for over a decade.

STUDY DESIGN: The classification system was derived through a literature review and expert opinion of experienced spine surgeons. In addition, a multicenter reliability and validity study of the system was conducted on a collection of trauma cases. OBJECTIVES: To define a novel classification system for subaxial cervical spine trauma that conveys information about injury pattern, severity, treatment considerations, and prognosis. To evaluate reliability and validity of this system. SUMMARY OF BACKGROUND DATA: Classification of subaxial cervical spine injuries remains largely descriptive, lacking standardization and prognostic information. METHODS: Clinical and radiographic variables encountered in subaxial cervical trauma were identified by a working section of the Spine Trauma Study Group. Significant limitations of existing systems were defined and addressed within the new system. This system, as well as the Harris and Ferguson & Allen systems, was applied by 20 spine surgeons to 11 cervical trauma cases. Six weeks later, the cases were randomly reordered and again scored. Interrater reliability, intrarater reliability, and validity were assessed. RESULTS: Each of 3 main categories (injury morphology, disco-ligamentous complex, and neurologic status) identified as integrally important to injury classification was assigned a weighted score; the injury severity score was obtained by summing the scores from each category. Treatment options were assigned based on threshold values of the severity score. Interrater agreement as assessed by intraclass correlation coefficient of the DLC, morphology, and neurologic status scores was 0.49, 0.57, and 0.87, respectively. Intrarater agreement as assessed by intraclass correlation coefficient of the DLC, morphology, and neurologic status scores was 0.66, 0.75, and 0.90, respectively. Raters agreed with treatment recommendations of the algorithm in 93.3% of cases, suggesting high construct validity. The reliability compared favorably to the Harris and Ferguson & Allen systems. CONCLUSION: The Sub-axial Injury Classification and Severity Scale provides a comprehensive classification system for subaxial cervical trauma. Early validity and reliability data are encouraging.

BACKGROUND: There is little consistency in the measurement of outcome in acute stroke trials, and this may complicate interpretation of the results and reduce the likelihood of detecting worthwhile drug effects. This study aims to investigate empirically the measures used to date and to give recommendations for future studies. SUMMARY OF COMMENT: A systematic review of all published randomized studies of acute stroke drug intervention was undertaken, and the measures used were recorded. Fifty-one studies involving 57 214 subjects were identified. These studies used 14 different measures of impairment, 11 different measures of activity, 1 measure of "quality of life," and 8 miscellaneous other measures. Timing of outcome assessments varied from 1 week to 1 year, with the modal time being 3 months. Many studies used ordinal measures but dichotomized results for analysis. Of the 51 studies included in the review, only 21 demonstrated benefit with the defined primary outcome measure. In several studies, however, post hoc analysis using varied outcome measures or varied cut points for dichotomizing outcomes resulted in positive results, whereas the primary study analysis failed to do so. CONCLUSIONS: There is no consensus on the level of outcome to be used, the method of measurement to be used, or the most appropriate timing of the assessment. It is recommended that future studies should include extended/instrumental activities and advanced mobility as components of the primary outcome measure, with outcome assessment being undertaken at 6 months. New initiatives in developing stroke-specific outcomes may address some of the current problems in the assessment of stroke outcomes

BACKGROUND: Atrial fibrillation (AF) has a deleterious impact on health-related quality-of-life (HRQoL), but measuring this outcome is difficult. A comprehensive, validated, disease-specific questionnaire to measure the spectrum of QoL domains affected by AF and its treatment is not available. We developed and validated a 20-item questionnaire, Atrial Fibrillation Effect on QualiTy-of-life (AFEQT), in a 6-center, prospective, observational study. METHODS AND RESULTS: Factor analyses established 4 conceptual domains (Symptoms, Daily Activities, Treatment Concern, and Treatment Satisfaction) from which individual domain and global scores were calculated. Participants from 6 centers completed the AFEQT at baseline, at month 1, and at month 3. Psychometric analyses included internal consistency and known-group validity. Test-retest reliability was assessed by comparing 1-month changes in scores among those with no change in therapy. Effect size was used to assess responsiveness after intervention. Among 219 patients age 62±11.9 years, 94% completed the AFEQT at baseline and 3 months; 66% had paroxysmal, 24% persistent, 5% longstanding persistent, and 5% permanent AF. Internal consistency was >0.88 for all scales. Lower AFEQT scores were observed with increased AF severity, categorized as asymptomatic, mild, moderate and severe, respectively: 71.2±20.6, 71.3±19.2, 57.9±19.0, and 42.0±21.2. Intraclass correlations for Overall, Symptoms, Daily Activities, Treatment Concern, and Satisfaction scores were 0.8, 0.5, 0.8, 0.7, and 0.7, respectively. Changes in 3-month scores were larger after ablation than with pharmacological adjustments, and both were greater than those observed in stable patients. CONCLUSIONS: This initial validation of AFEQT supports its use as an outcome in studies and a means to clinically follow patients with AF.

BACKGROUND: In 2000, a landmark study showed that women who graduated from U.S. medical schools from 1979 through 1997 were less likely than their male counterparts to be promoted to upper faculty ranks in academic medical centers. It is unclear whether these differences persist. METHODS: We merged data from the Association of American Medical Colleges on all medical school graduates from 1979 through 2013 with faculty data through 2018, and we compared the percentages of women who would be expected to be promoted on the basis of the proportion of women in the graduating class with the actual percentages of women who were promoted. We calculated Kaplan-Meier curves and used adjusted Cox proportional-hazards models to examine the differences between the early cohorts (1979-1997) and the late cohorts (1998-2013). RESULTS: The sample included 559,098 graduates from 134 U.S. medical schools. In most of the cohorts, fewer women than expected were promoted to the rank of associate or full professor or appointed to the post of department chair. Findings were similar across basic science and clinical departments. In analyses that included all the cohorts, after adjustment for graduation year, race or ethnic group, and department type, women assistant professors were less likely than their male counterparts to be promoted to associate professor (hazard ratio, 0.76; 95% confidence interval [CI], 0.74 to 0.78). Similar sex disparities existed in promotions to full professor (hazard ratio, 0.77; 95% CI, 0.74 to 0.81) and appointments to department chair (hazard ratio, 0.46; 95% CI, 0.39 to 0.54). These sex differences in promotions and appointments did not diminish over time and were not smaller in the later cohorts than in the earlier cohorts. The sex differences were even larger in the later cohorts with respect to promotion to full professor. CONCLUSIONS: Over a 35-year period, women physicians in academic medical centers were less likely than men to be promoted to the rank of associate or full professor or to be appointed to department chair, and there was no apparent narrowing in the gap over time. (Funded by the University of Kansas Medical Center Joy McCann Professorship for Women in Medicine and the American Association of University Women.).

BACKGROUND: In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document. METHODS: ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work. RESULTS: ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost. CONCLUSION: The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Two metabolically distinct types of bone cell populations were isolated from mouse calvaria by a repetitive digestive procedure with a mixture of collagenase and trypsin. Cells released early in the digestion showed approximately two fold increases in cAMP when treated with either parathormone or calcitonin. These populations were denoted CT type. Later eluting cells showed larger parathormone-induced increases in cAMP but did not respond to calcitonin. These populations were denoted PT type. Six metabolic and enzymatic activities were measured in the two types of populations: acid and alkaline phosphatases, hyaluronate synthesis, citrate decarboxylation, prolyl hydroxylase, and general protein synthesis. Although each of these activities was present in both cell types, the basal levels of acid phosphatase and hyaluronate synthesis were higher in the CT cells, whereas alkaline phosphatase, citrate decarboxylation, and prolyl hydroxylase were higher in the PT cells. Parathormone stimulated acid phosphatase and hyaluronate synthesis by 100–200% only in the CT cells; it inhibited alkaline phosphatase, citrate decarboxylation, and prolyl hydroxylase by 75–90% only in the PT cells. Calcitonin alone had no effect on any of these activities other than cAMP production, but it inhibited the action of parathormone in the CT cells. The sensitivities, time courses of development, and magnitudes of these hormonal effects were similar to those observed previously in intact calvaria, indicating that the isolated cell system is a reliable model for the study of bone metabolism. Based on the metabolic responses of the cells, we postulate that the CT type of populations is enriched in osteoclasts and, possibly, osteocytes, and the PT type of population is enriched in osteoblasts. (Endocrinology99: 526, 1976)

The suprascapular ligament seems to serve no defined function in the human. A comparative study was undertaken to elucidate its function. The suprascapular region was dissected in species representing seven existing primate families and six subprimate families. A striking dichotomy of pattern was observed. In the New World primates, the suprascapular ligament appeared to be continuous with the coracoclavicular ligament; the former merely served to increase the area of bony attachment of the coracoclavicular ligament. In the Old World monkeys and subprimate mammals, the suprascapular ligament was entirely absent. The human anatomy was comparable to that found in the New World primates. This dichotomy of pattern seems to be related to the function of the upper extremity in the different classes of mammals.

Thirty-one patients with large, focal cerebral demyelinating lesions are reported. Twenty-four patients had solitary lesions and 7 had multiple foci, the latter apparently of identical age. The lesions presented clinically and radiologically as brain tumors (gliomas or metastases) or as multiple cysts. Six patients were older than 57 years (2 in their 70s) at the onset of their symptoms. The demyelinating nature of the lesions was established through biopsy in each patient and all improved significantly after corticosteroid therapy. Three patients developed additional lesions during the follow-up periods ranging from 9 months to 12 years consistent with the course of multiple sclerosis. Twenty-eight patients did not develop additional lesions. These included 6 patients with multiple lesions at the onset. In 1 of the patients, the first symptoms developed 10 days after receiving vaccination against influenza. Two patients had concomitant malignancy (chronic monomyelogenous leukemia and retroperitoneal seminoma respectively) and 1 patient developed immunoblastic sarcoma in the opposite hemisphere after biopsy diagnosis and steroid treatment of her demyelinating lesion. Tumor-like masses of demyelination may occupy an intermediate position between multiple sclerosis and postinfectious/postvaccination encephalitis. The clinical course (history of vaccination in one instance, acute onset, good response to corticosteroids, no clinical or radiological evidence of new lesions in the great majority of patients) favored postinfectious/postvaccination encephalitis. Lesion size however greatly exceeded that of the small foci of perivenous demyelination seen in typical postinfectious/postvaccination encephalitis and tended to present as space-occupying masses.

BACKGROUND: Currently, specific triage criteria, such as blood pressure, respiratory status, Glasgow Coma Scale, and mechanism of injury are used to categorize trauma patients and prioritize emergency department (ED) and trauma team responses. It has been demonstrated in previous literature that an abnormal shock index (SI = heart rate [HR]/systolic blood pressure, >0.9) portends a worse outcome in critically ill patients. Our study looked to evaluate the SI calculated in the field, on arrival to the ED, and the change between field and ED values as a simple and early marker to predict mortality in traumatically injured patients. METHODS: A retrospective chart review of the trauma registry of an urban level I trauma center. Analysis of 2,445 patients admitted over 5 years with records in the trauma registry of which 1,166 also had data for the field SI. An increase in SI from the field to the ED was defined as any increase in SI regardless of the level of the magnitude of change. RESULTS: Twenty-two percent of patients reviewed had an ED SI >0.9, with a mortality rate of 15.9% compared with 6.3% in patients with a normal ED SI. An increase in SI between the field and ED signaled a mortality rate of 9.3% versus 5.7% for patients with decreasing or unchanged SI. Patients with an increase in SI of >or=0.3 had a mortality rate of 27.6% versus 5.8% for patients with change in SI of <0.3. CONCLUSION: Trauma patients with SI >0.9 have higher mortality rates. An increase in SI from the field to the ED may predict higher mortality. The SI may be a valuable addition to other ED triage criteria currently used to activate trauma team responses.

Children with language impairment (LI) have been shown to be at risk for reading disability (RD) and behavior disorder (BD). Previous research has not determined the specific pattern of these conditions associated with LI. This study sought to determine if the behavior disorder and reading problems represented different outcomes or if these conditions occurred together when found with LI. A group of 581 second-grade children, including 164 children with LI, were examined for spoken language, reading, and behavior disorder. The data for each of these areas were examined as dimensional traits and as clinical categorical traits. Reading and spoken language were found to be strongly correlated (r = .68); RD was found in 52 % of the children with LI and in only 9 % of the controls. Scores of parent ratings for BD were also significantly correlated with spoken language scores (r = .29). Clinical levels of BD were found in 29% of the children with LI and 19% of the controls. An examination of the co-occurrence of clinical levels of BD, RD, and LI showed BD in children with LI to be conditioned by the child's reading status. The data indicated that whereas RD was directly associated with BD, the association of LI with BD required the mediation of RD.

Two hypolipidemic compounds [ 4-chloro-6(2,3-xylidino)-2-pyrimidinyl-thio] acetic acid, and 2-chloro-5(3,5-dimethylpiperidinosufony)benzoic acid (tibric acid) greatly increased the number of peroxisomes (microbodies) in liver cells of rats and mice. This augmented peroxisome population was accompanied by significant elevation of liver catalase activity. These two hypolipidemic peroxisome proliferators are structurally different from ethyl a-p-chlorophenozyisobutyrate (clofibrate) and other hypolipidemic, arylocyisobutyrate derivatives which cause hepatic peroxisome proliferation. Induction of peroxisome proliferation by these structurally unrelated hypolipidemic compounds suggests a possible relation between hepatic peroxisome proliferation and hypolipidemia.

Spine surgery has experienced much technological innovation over the past several decades. The field has seen advancements in operative techniques, implants and biologics, and equipment such as computer-assisted navigation and surgical robotics. With the arrival of real-time image guidance and navigation capabilities along with the computing ability to process and reconstruct these data into an interactive three-dimensional spinal "map", so too have the applications of surgical robotic technology. While spinal robotics and navigation represent promising potential for improving modern spinal surgery, it remains paramount to demonstrate its superiority as compared to traditional techniques prior to assimilation of its use amongst surgeons.The applications for intraoperative navigation and image-guided robotics have expanded to surgical resection of spinal column and intradural tumors, revision procedures on arthrodesed spines, and deformity cases with distorted anatomy. Additionally, these platforms may mitigate much of the harmful radiation exposure in minimally invasive surgery to which the patient, surgeon, and ancillary operating room staff are subjected.Spine surgery relies upon meticulous fine motor skills to manipulate neural elements and a steady hand while doing so, often exploiting small working corridors utilizing exposures that minimize collateral damage. Additionally, the procedures may be long and arduous, predisposing the surgeon to both mental and physical fatigue. In light of these characteristics, spine surgery may actually be an ideal candidate for the integration of navigation and robotic-assisted procedures.With this paper, we aim to critically evaluate the current literature and explore the options available for intraoperative navigation and robotic-assisted spine surgery.

Physical therapists require an accurate, reliable method for measuring muscle strength. They often use manual muscle testing or hand-held dynametric muscle testing (DMT), but few studies document the reliability of MMT or compare the reliability of the two types of testing. We designed this study to determine the intrarater reliability of MMT and DMT. A physical therapist performed manual and dynametric strength tests of the same five muscle groups on 11 patients and then repeated the tests two days later. The correlation coefficients were high and significantly different from zero for four muscle groups tested dynametrically and for two muscle groups tested manually. The test-retest reliability coefficients for two muscle groups tested manually could not be calculated because the values between subjects were identical. We concluded that both MMT and DMT are reliable testing methods, given the conditions described in this study. Both testing methods have specific applications and limitations, which we discuss.