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Barker MS, Knight JL, Dean RJ, Mandelstam S, Richards LJ, Robinson GA. Verbal Adynamia and Conceptualization in Partial Rhombencephalosynapsis and Corpus Callosum Dysgenesis. Cogn Behav Neurol 2021; 34:38-52. [PMID: 33652468 DOI: 10.1097/wnn.0000000000000261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 07/02/2020] [Indexed: 11/26/2022]
Abstract
Verbal adynamia is characterized by markedly reduced spontaneous speech that is not attributable to a core language deficit such as impaired naming, reading, repetition, or comprehension. In some cases, verbal adynamia is severe enough to be considered dynamic aphasia. We report the case of a 40-year-old, left-handed, male native English speaker who presented with partial rhombencephalosynapsis, corpus callosum dysgenesis, and a language profile that is consistent with verbal adynamia, or subclinical dynamic aphasia, possibly underpinned by difficulties selecting and generating ideas for expression. This case is only the second investigation of dynamic aphasia in an individual with a congenital brain malformation. It is also the first detailed neuropsychological report of an adult with partial rhombencephalosynapsis and corpus callosum dysgenesis, and the only known case of superior intellectual abilities in this context.
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Affiliation(s)
- Megan S Barker
- Neuropsychology Research Unit, School of Psychology, The University of Queensland, St Lucia, Brisbane, Australia
- Taub Institute, Columbia University Medical Center, New York, New York
| | - Jacquelyn L Knight
- Neuropsychology Research Unit, School of Psychology, The University of Queensland, St Lucia, Brisbane, Australia
| | - Ryan J Dean
- Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Australia
| | - Simone Mandelstam
- Department of Radiology, University of Melbourne, Royal Children's Hospital, Parkville, Victoria, Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
- Florey Institute of Neuroscience and Mental Health, Melbourne, Victoria, Australia
| | - Linda J Richards
- Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Australia
- School of Biomedical Sciences, The University of Queensland, St. Lucia, Brisbane, Australia
| | - Gail A Robinson
- Neuropsychology Research Unit, School of Psychology, The University of Queensland, St Lucia, Brisbane, Australia
- Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Australia
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Spencer-Smith M, Knight JL, Lacaze E, Depienne C, Lockhart PJ, Richards LJ, Heron D, Leventer RJ, Robinson GA, Gibson E, Giraudat K, McIlroy A, Paul LK, Siffredi V, Bahlo M, Barker M, Blondiaux E, Edwards TJ, Garel C, Heide S, Keren B, Mandelstam SA, Marsh APL, McGillivray G, Mignot C, Moutard M, Nava C, Pope K, Rastetter A, Stephenson SEM, Valence S, de Villemeur TB, Wood A, Anderson V, Sherr EH. Callosal agenesis and congenital mirror movements: outcomes associated with DCC mutations. Dev Med Child Neurol 2020; 62:758-762. [PMID: 32060908 DOI: 10.1111/dmcn.14486] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/24/2019] [Indexed: 11/29/2022]
Abstract
Pathogenic variants in the gene encoding deleted in colorectal cancer (DCC) are the first genetic cause of isolated agenesis of the corpus callosum (ACC). Here we present the detailed neurological, brain magnetic resonance imaging (MRI), and neuropsychological characteristics of 12 individuals from three families with pathogenic variants in DCC (aged 8-50y), who showed ACC and mirror movements (n=5), mirror movements only (n=2), ACC only (n=3), or neither ACC nor mirror movements (n=2). There was heterogeneity in the neurological and neuroimaging features on brain MRI, and performance across neuropsychological domains ranged from extremely low (impaired) to within normal limits (average). Our findings show that ACC and/or mirror movements are associated with low functioning in select neuropsychological domains and a DCC pathogenic variant alone is not sufficient to explain the disability. WHAT THIS PAPER ADDS: Neuropsychological impairment severity is related to presence of mirror movements and/or agenesis of the corpus callosum. A DCC pathogenic variant in isolation is associated with the best prognosis.
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Affiliation(s)
- Megan Spencer-Smith
- Turner Institute for Brain and Mental Health and School of Psychological Sciences, Monash University, Melbourne, Victoria, Australia.,Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Jacquelyn L Knight
- School of Psychology, The University of Queensland, St Lucia, Brisbane, Australia
| | - Emmanuelle Lacaze
- Service de Neuropédiatrie, Centre de Référence pour les Malformations et Maladies Congénitales du Cervelet, Paris, France
| | | | - Christel Depienne
- INSERM, U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle Épinière (ICM), Paris, France.,Institute of Human Genetics, University Hospital Essen, University Duisburg-Essen, Essen, Germany.,IGBMC, CNRS UMR 7104/INSERM U964/Université de Strasbourg, Illkirch, France
| | - Paul J Lockhart
- Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia.,Bruce Lefroy Centre for Genetic Health Research, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Linda J Richards
- Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Australia.,School of Biomedical Sciences, The University of Queensland, St. Lucia, Brisbane, Australia
| | - Delphine Heron
- Department of Genetics, APHP, Armand-Trousseau and Pitié Salpêtrière Hospital, Paris, France.,Reference Center for Intellectual Disability of Rare Causes, Paris, France
| | - Richard J Leventer
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia.,Department of Neurology, Royal Children's Hospital, Melbourne, Australia
| | - Gail A Robinson
- School of Psychology, The University of Queensland, St Lucia, Brisbane, Australia.,Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Australia
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Baker RA, Knight JL. The OXICAB trial: cerebral oximetry in adult cardiac surgical patients. J Extra Corpor Technol 2006; 38:77. [PMID: 16637536 PMCID: PMC4680778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Affiliation(s)
- R A Baker
- Depart of Cardiac and Thoracic Surgery, Flinders Medical Centre and Flinders University, Bedford Park, Adelaide, South Australia, Australia
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Abstract
BACKGROUND Studies of neuropsychological outcome following coronary artery bypass graft surgery (CABG) have traditionally dichotomised patients as "impaired" or "unimpaired". This conceals the potential heterogeneity of deficits due to different mechanisms and sites of brain injury. OBJECTIVES To explore neuropsychological outcome following CABG and determine to what extent it conforms to prototypic cortical and/or subcortical neurobehavioral syndromes and whether different intraoperative physiologic measures are associated with different subtypes of neuropsychological outcome. METHODS Neuropsychological tests were administered to 85 patients before and after elective CABG and to 50 matched normal control subjects. Pre- to postoperative change scores were computed using standardised regression based norms. Change scores on selected memory measures were subjected to cluster analysis to identify qualitatively distinct subtypes of memory outcome. Emergent clusters were compared on non-memory measures, intraoperative physiologic measures, and demographic variables. RESULTS Three subtypes of memory outcome were identified: memory spared (48% of patients), retrieval deficit (35%), and encoding/storage deficit (17%). Contrary to expectation, the subgroups were indistinguishable on measures of confrontation naming and manual dexterity and on intraoperative cardiac surgical physiologic measures and demographic variables. The encoding/storage deficit subgroup exhibited executive dysfunction. CONCLUSIONS Heterogeneous profiles of neuropsychological dysfunction were found following CABG although they did not tightly conform to prototypic cortical and subcortical neurobehavioral syndromes. This challenges the value and appropriateness of the common practice of collapsing individual test scores to arrive at a single figure to define "impairment". Whether different subtypes of neuropsychological outcome are caused by different pathophysiologic mechanisms remains unknown.
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Affiliation(s)
- A C Kneebone
- Department of Psychological Medicine, Flinders Medical Centre, Bedford Park 5042, Australia.
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Abstract
The safety and efficacy of off-pump coronary artery bypass surgery with the aid of the Octopus Tissue Stabilizer (Octopus OPCAB), in comparison to conventional on-pump coronary artery bypass surgery (CPB-CABG), was examined by a systematic assessment of the peer-reviewed literature. The limited comparative data suggested that there was no difference in safety outcomes between Octopus OPCAB and CPB-CABG. The paucity of efficacy data reported in the higher level comparative studies meant that it was impossible to assess whether Octopus OPCAB was more efficacious than CPB-CABG. The evidence base for the procedure was deemed inadequate and an audit of the procedure was recommended.
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Affiliation(s)
- N A Scott
- ASERNIP-S, Royal Australasian College of Surgeons, Box 688 North Adelaide, SA 5006, Australia
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Bennetts JS, Arnolda LF, Cullen HC, Knight JL, Baker RA, McKitrick DJ. Coronary artery baroreceptor-mediated changes in arterial pressure: a pilot study in conscious and anaesthetized sheep. Clin Exp Pharmacol Physiol 2001; 28:768-72. [PMID: 11560126 DOI: 10.1046/j.1440-1681.2001.03522.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. Evidence suggesting the presence of coronary artery baroreceptors on coronary arteries has existed for over 30 years. 2. Evidence that activation of ventricular mechanoreceptors can elicit cardiovascular changes has been challenged, with those changes now thought to be due to coronary artery mechanoreceptors. 3. Studies have suggested that coronary artery mechanoreceptors act as coronary baroreceptors with a role in cardiovascular regulation. However, all evidence to date has been obtained in anaesthetized animal models in physiologically compromised intra-operative states. 4. The purpose of the present study was to design an ovine model that would allow the discrete stretch of coronary arteries without causing ischaemia or changing flow or intra-arterial pressure and that would confirm results seen in previous studies. In addition, the possibility that the technique could be used for studies of coronary artery baroreflexes in conscious sheep was investigated. 5. Controlled stretch of the proximal left anterior descending coronary artery elicited decreases in arterial pressure without changes in heart rate or electrocardiographic activity in halothane-anaesthetized sheep. Similar results were demonstrated in conscious sheep after surgical recovery of up to 2 weeks. 6. The present study supports the possibility that coronary artery baroreceptors exist and likely have a role in cardiovascular regulation. The results of the present study in anaesthetized sheep are in agreement with previous results in anaesthetized animals, but also provide the first demonstration of coronary baroreceptor activity in a conscious animal model, underscoring the potential use of the model in the study of coronary artery baroreceptors in the intact animal.
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Affiliation(s)
- J S Bennetts
- Department of Cardiac Surgery Research, Flinders Medical Centre, Bedford Park, South Australia
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Baker RA, Andrew MJ, Ross IK, Knight JL. The Octopus II stabilizing system: biochemical and neuropsychological outcomes in coronary artery bypass surgery. Heart Surg Forum 2001; 4 Suppl 1:S19-23. [PMID: 11178303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2000] [Indexed: 02/18/2023]
Abstract
INTRODUCTION The aim of this study was to determine if coronary artery bypass graft (CABG) surgery performed utilizing the Octopus II stabilizing system provides myocardial and cerebral protection comparable to traditional CABG surgery utilizing cardiopulmonary bypass (CPB). METHODS Elective patients requiring surgery for double or triple vessel disease were randomized to receive either conventional CABG with CPB (n = 14) or OPCAB using the Octopus II stabilizing system (n = 12), after receiving institutional approval and written consent. Exclusion criteria included previous cardiac surgery, recent myocardial infarction, and previous cerebrovascular disease. Troponin T (TnT) was measured preoperatively and at 2, 4, 6, 8, 10, 12, 24, and 72 hours after initiation of grafting. Neuropsychological assessments (10 measures) were performed in the week prior to surgery, one week, and six months after surgery. RESULTS Troponin T release was reduced in the OPCAB patients at all time points (repeated measures ANOVA p = 0.043), reaching significance at 8, 10 and 12 hours (p = 0.033, 0.038, 0.019). Other factors (composite clinical end point (prolonged LOS or ICU stay or 30-day mortality), infarction, and intubation time) did not show any significant differences between the two groups. The incidence of neuropsychological deficits was not different between the two groups at both seven-day and six-month follow-up assessments. CONCLUSIONS Decreased TnT release suggests a myocardial benefit for the OPCAB procedure. A neuropsychological benefit remains to be demonstrated.
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Affiliation(s)
- R A Baker
- Cardiac Surgical Research Group, Department of Cardiothoracic Surgery, Division of Medicine, Flinders Medical Centre, Bedford Park, South Australia 5042, Australia.
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Abstract
It is well recognized that cardiac surgery with cardiopulmonary bypass can potentially induce a wide spectrum of central nervous system (CNS) sequelae. Our awareness of the prevalence of these CNS complications is dependent on the validity of the available diagnostic methods. Current assessment methods designed to detect both focal and diffuse cerebral ischemia include neurologic examination, imaging techniques, biochemical markers, neuropsychologic assessment, and patient perceived outcomes. These techniques vary in their sensitivity and specificity, as well as feasibility for use in everyday clinical practice. There are currently only limited standardized methodologic guidelines for the assessment of CNS complications after cardiac surgery, which has resulted in considerable interstudy variability in the identification and reporting of outcomes. The application of clearly definable endpoints for reporting of CNS outcomes would be beneficial. The wealth of available data suggests that the incidence of overt CNS injury such as stroke has declined since the 1980s and is now approximately 2%, whereas evidence suggests that up to one third of cardiac surgery patients experience postoperative cognitive deficits. One of the clear strengths of the current era is the recognition of CNS injury associated with cardiac surgery, and the quest to improve our understanding of these outcomes. The application of more uniform assessment and reporting practices is surely vital to the continued advancement of cardiac surgery.
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Affiliation(s)
- R A Baker
- Cardiac Surgical Research Group, Flinders Medical Centre Adelaide, South Australia.
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Abstract
BACKGROUND There is convincing evidence to suggest that depression significantly increases the risk of mortality following myocardial infarction. There are few data concerning depression as a risk factor for mortality following cardiac surgery. The aim of the present observational study was to determine if preoperative depressive symptoms resulted in an increased risk of late mortality following cardiac surgery. METHODS Preoperative assessments of depressive symptoms were performed on 158 patients undergoing coronary artery bypass surgery. Elevated preoperative depression symptoms were defined as a depression anxiety stress scale score of > or = 10. RESULTS Twenty-four of the 158 patients ( 15.2%) were classified as having elevated preoperative depressive symptoms. Patients were followed for a median of 25 months (range: 4-38 months). Three of the 24 patients (12.5%) with preoperative depressive symptoms died within the follow-up period, compared with three of the 134 (2.2%) non-depressed patients (odds ratio: 6.24; 95% CI: 1.18-32.98; P = 0.046). There were no other group differences on variables including population demographics, medical risk factors, surgical parameters, and indices of postoperative morbidity. CONCLUSIONS Elevated depressive symptoms before coronary bypass surgery may be a significant predictor of late death. Prospective studies evaluating the prevalence of depressive symptoms in cardiac surgical patients and their effect on long-term outcome must be undertaken.
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Affiliation(s)
- R A Baker
- Cardiac Surgical Research Unit, Flinders Medical Centre, Queen Elizabeth Hospital, Adelaide, South Australia.
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Abstract
OBJECTIVE To compare the incidence of neuropsychologic deficits 1 week and 6 months after coronary artery bypass graft (CABG) surgery (extracardiac) and valve surgery with or without CABG surgery (intracardiac) using reliable change indices to define the incidence of neuropsychologic deficits. DESIGN Prospective study. SETTING Cardiac surgical unit in a university teaching hospital. PARTICIPANTS Patients scheduled for elective multiple-graft (> or =3 grafts) CABG surgery (n = 59), or elective valve surgery (with or without concomitant CABG surgery) (n = 50) and a matched sample of nonsurgical controls (n = 53). INTERVENTIONS Neuropsychologic assessments were performed 1 day before surgery, 7 days and 6 months after surgery. MEASUREMENTS AND MAIN RESULTS The 7-day assessment showed no significant differences between valve surgery patients and CABG surgery patients in the incidence of neuropsychologic deficits. When reassessed 6 months postoperatively, the valve group displayed a significantly higher incidence of deficits on the digit symbol test compared with the CABG group (valve 26.7% v CABG 6.8%). In the CABG group, there was a significant change in the incidence of deficits per patient from 7 days to 6 months (p = 0.03) that was not evident in the valve group. CONCLUSION There are some differences in the neuropsychologic outcome of extracardiac and intracardiac surgery. Patients undergoing isolated CABG surgery showed a greater reduction in the incidence of persisting deficits at 6 months than patients undergoing valve surgery with or without CABG surgery. This finding warrants further investigation, with particular attention to patients undergoing combined valve and coronary artery procedures.
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Affiliation(s)
- M J Andrew
- Department of Surgery, Flinders Medical Centre and Flinders University of South Australia, Adelaide
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Abstract
OBJECTIVES mood disorders and neuropsychological deficits are both commonly reported occurrences after cardiac surgery. We examined the relationship between mood state and postoperative cognitive deficits in this population. METHODS assessments of neuropsychological functions and mood state (depression, anxiety, stress scales; DASS) were performed preoperatively and postoperatively on 147 patients undergoing cardiac surgery. RESULTS the incidence of preoperative depression, anxiety, and stress symptomatology was 16%, 27%, and 16%, respectively. The incidence of postoperative anxiety symptomatology significantly increased to 45% (p<0.001), while the incidence of depression and stress symptomatology remained stable (19% and 15%, respectively; ns). Changes in mood state did not influence changes in neuropsychological performance. Preoperative mood was a strong predictor of postoperative mood, and was related to postoperative deficits on measures of attention and memory. CONCLUSIONS an assessment of preoperative mood is critical in identifying patients at risk of postoperative mood disorders and neuropsychological deficits. Measures assessing somatic manifestations of anxiety may not be suitable for a surgical population.
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Affiliation(s)
- M J Andrew
- Cardiac Surgical Research Group, Department of Medicine, Flinders Medical Centre and Flinders University of South Australia, Bedford Park, South Australia 5042, Adelaide, Australia
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Knight JL, Helming C. Collarless polished tapered impaction grafting of the femur during revision total hip arthroplasty: pitfalls of the surgical technique and follow-up in 31 cases. J Arthroplasty 2000; 15:159-65. [PMID: 10708079 DOI: 10.1016/s0883-5403(00)90088-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Impacting morcellized allograft bone into the femur during revision total hip arthroplasty is a simple concept with the goal of rebuilding femoral bone stock and providing secure fixation to the femoral stem. Using the collarless polished tapered (CPT, Zimmer, Warsaw, IN) stem impaction grafting system, we became concerned about the discrepancy between the straightforward concept and precise execution of the technique. In this study, we examined 31 consecutive procedures to determine intraoperative difficulties and report on the clinical outcome of 30 cases at an average follow-up of 31 months. Modified Harris Hip Scores averaged 41 points preoperatively and improved to 86 points at follow-up. Nineteen cases were performed on intact femora, whereas 12 cases had disrupted femoral integrity, either extended trochanteric osteotomy or periprosthetic fracture. Successful outcome was seen in all cases with an intact femur, and restoration of femoral integrity was key to successful outcome in cases with compromised femoral integrity. Among cases with disrupted femoral integrity, 3 distal fractures occurred as a result of the rigid CPT cement plug, and 2 complete femoral fractures occurred as a result of bone impaction, for a technique-related fracture rate of 16%. Difficulty packing bone distally occurred in 94% of cases and was associated with varus and valgus stem alignment and medial and lateral stem displacement. Complete cement mantles were seen in 77% of cases. No stem subsidence was seen in 15 of 30 cases (50%). Stem subsidence of <5 mm was seen in 10 of 30, stem subsidence of 6 to 8 mm was seen in 4 of 30, and stem subsidence of >10 mm was seen in 1 patient (4%). Of the patients, 87% thought the procedure improved their function, and 97% would recommend it to a friend with a failed femoral component. Although we hope that the instruments for this procedure can improve, we endorse the concept of impaction grafting with the CPT stem as a successful way of dealing with revision femoral surgery.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Redmond, Washington 98052, USA
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Abstract
Manually operated injection systems are routinely used to deliver polymethyl methacrylate during cemented femoral component primary total hip arthroplasty (THA). The goal of cement delivery is to achieve sufficient intrusion of cement into the trabecular bone of the prepared femur so that the femoral component is securely bonded to the femur. We have observed posterior distal cement extrusion (PDCE), which appears to be secondary to too-successful pressurization. We sought to quantify and offer a possible explanation for this phenomenon. Eight patients with PDCE were identified, with an estimated incidence range of 0.90%, to 1.6% of primary cemented femoral component THA. All occurred in female patients of small stature. Endosteal canal diameters were also small, averaging 11 mm, 10 cm from the lesser trochanter. The PDCE occurred at an average distance of 9.8 cm from the midpoint of the lesser trochanter, and was most easily visualized on the lateral radiograph where it resided in the posterior soft tissues. Examination of 49 human femora showed 1 or more vascular channels in the posterior aspect of the femur in all specimens. The most proximal vascular channel averaged 10.1 cm distal to the lesser trochanter and had an average lumen diameter of 1 mm. The vascular channel contained an artery and 2 veins by histologic examination. We postulate that PDCE represents the escape of low-viscosity cement out of the vascular channel, and laboratory simulation supports this possibility. Because this finding has not previously been reported, we hoped that other centers will look closely for this phenomenon.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Redmond, Washington 98052, USA
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Abstract
With an increasingly aging population, heart failure is a major health issue, affecting more than 10% of the population over 65 years of age, and costing hundreds of millions of dollars per year for ongoing care. Even with maximal medical therapy, annual mortality rates of in excess of 25% are commonly reported. Over the last three decades, various surgical approaches have been examined in the hope of improving the outcome of congestive cardiac failure. These procedures range from simple coronary revascularisation to left ventricular reduction surgery and cardiac transplantation. Although of value in selected situations, no surgical approach, beyond transplantation, has had significant impact on the outcome of heart failure. In the last decade, development in the area of mechanical support for the failing heart has continued to expand at a rapid rate. Strong evidence now exists to show that in many patients with advanced heart failure, prolonged mechanical support results in significant myocardial recovery. There are currently several mechanical support devices available for clinical use, although most are considered experimental in this country. These devices are expensive and are not without significant complications, but early results of their use as either a bridge to transplantation or as a stand alone treatment, have been very encouraging. Currently available mechanical assist devices are described, with discussion of indications for implantation, complications and results of their use.
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Affiliation(s)
- J L Knight
- Cardiac Surgery, Flinders Medical Centre, Adelaide, SA
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Abstract
BACKGROUND We compared postoperative neuropsychological dysfunction after minimally invasive direct coronary artery bypass grafting (MIDCAB) operation with coronary artery bypass graft operations using cardiopulmonary bypass. METHODS Neuropsychological assessment was performed preoperatively and before discharge on 7 patients undergoing MIDCAB procedures, 9 patients undergoing single-graft cardiopulmonary bypass operation, and 27 patients undergoing multiple-graft cardiopulmonary bypass operation. From a matched control group of 40 normal subjects reliable change indices were derived for each measure and used to determine the incidence of postoperative decline. RESULTS There was little difference between the MIDCAB and single-graft cardiopulmonary bypass groups on the incidence of neuropsychologic decline. However, the multiple-graft cardiopulmonary bypass group had a significantly higher incidence of decline than the MIDCAB and single-graft cardiopulmonary bypass groups on specific neuropsychologic measures, coupled with a significantly greater number of postoperative deteriorations per patient. CONCLUSIONS The elimination of cardiopulmonary bypass does not prevent neuropsychological dysfunction after cardiac operation as patients undergoing MIDCAB and single-graft cardiopulmonary bypass experience similar deteriorations in performance. However, the deterioration is markedly worsened when the number of surgical grafts is increased.
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Affiliation(s)
- M J Andrew
- Department of Surgery, Flinders Medical Centre and Flinders University of South Australia, Adelaide, Australia
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Knight JL, Weaver DF. A computational quantitative structure-activity relationship study of carbamate anticonvulsants using quantum pharmacological methods. Seizure 1998; 7:347-54. [PMID: 9808108 DOI: 10.1016/s1059-1311(05)80001-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
A pattern recognition quantitative structure-activity relationship (QSAR) study has been performed to determine the molecular features of carbamate anticonvulsants which influence biological activity. Although carbamates, such as felbamate, have been used to treat epilepsy, their mechanisms of efficacy and toxicity are not completely understood. Quantum and classical mechanics calculations have been exploited to describe 46 carbamate drugs. Employing a principal component analysis and multiple linear regression calculations, five crucial structural descriptors were identified which directly relate to the bioactivity of the carbamate family. With the resulting mathematical model, the biological activity of carbamate analogues can be predicted with 85-90% accuracy.
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Affiliation(s)
- J L Knight
- Department of Chemistry, Queen's University, Kingston, Ontario, Canada
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Knight JL, Atwater RD, Guo J. Clinical results of the midstem porous-coated anatomic uncemented femoral stem in primary total hip arthroplasty: a five- to nine-year prospective study. J Arthroplasty 1998; 13:535-45. [PMID: 9726319 DOI: 10.1016/s0883-5403(98)90053-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The clinical and radiologic results of an inclusive series of 60 patients (70 hips) who had primary total hip arthroplasty using the porous-coated anatomic (PCA) midstem femoral prosthesis was prospectively studied. The midstem component features a proximal circumferential porous bead coating similar to the PCA primary stem; but increased proximal thickness, increased length, and a distal anterior curve for additional rotational stability. The mean Harris Hip Score rose from 39.5 points before surgery to 91.3 points at a minimum follow-up of 5 years (average, 69 months); 88% were good or excellent. Moderate or severe thigh pain on a visual analogue scale was reported by 30% of cases, and was more common in women. Radiographic analysis indicated preservation of proximal bone stock and bony ingrowth in 87%, but stem subsidence in 9%. One stem has been revised for subsidence and thigh pain (1.4%), and one stem is radiographically loose, but the patient refuses surgical revision. Endosteal osteolysis was rarely seen (2.8%) and was benign in appearance. Acetabular components used included 63 nonmodular PCA metal-backed cups and 7 hemispherical porous ingrowth cups fixed with screws. One PCA cup was revised for loosening (1.4%), and one is radiographically loose but stable (1.4%). Only one cup exhibited an area of osteolysis. At this intermediate follow-up the clinical outcome of the midstem component is stable and excellent. The radiographic results appear superior to the PCA primary stem, with a lower incidence of stem subsidence and osteolysis. The prevalence of thigh pain is a concern and we recommend regular follow-up of patients with the midstem femoral implant, and the use of a visual analogue thigh pain scale when any femoral prosthesis is evaluated.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Redmond, Washington 98052, USA
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Knight JL. Genu recurvatum deformity secondary to partial proximal tibial epiphyseal arrest: case report. Am J Knee Surg 1998; 11:111-5. [PMID: 9586741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Eastside Specialty Center, Redmond, Washington 98052, USA
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Abstract
BACKGROUND A method of defining change in neuropsychologic test scores that accounts for test reliability and practice effects was applied to determine accurately the incidence of acquired neuropsychologic deficits after coronary artery bypass grafting. METHODS Neuropsychologic assessment was performed on 50 patients before and at 7 days after either hypothermic or normothermic coronary artery bypass grafting. From a matched control group of 24 normal subjects who were examined twice over a similar interval, reliable change indices that controlled for measurement error and practice effects were calculated for each neuropsychologic measure. With the use of these indices, the incidence of postoperative decline among the study patients was determined. For comparison, the incidence of decline using the "one standard deviation" criterion also was calculated. RESULTS Comparing the reliable change and standard deviation methods, statistically significant differences in the incidence of decline were observed in 5 of 11 neuropsychologic measures. The reliable change method identified more patients with neuropsychologic deficits on most measures. CONCLUSIONS The control of measurement error and practice effects can alter significantly the calculated incidence of neuropsychologic impairment after coronary artery bypass grafting.
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Affiliation(s)
- A C Kneebone
- Department of Health Psychology, Flinders Medical Centre, Adelaide, South Australia, Australia
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Knight JL, Sherer D, Guo J. Blood transfusion strategies for total knee arthroplasty: minimizing autologous blood wastage, risk of homologous blood transfusion, and transfusion cost. J Arthroplasty 1998; 13:70-6. [PMID: 9493540 DOI: 10.1016/s0883-5403(98)90077-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In this nonrandomized study, alternative strategies were suggested to 10 orthopaedic surgeons to minimize autologous blood wastage, the risk of homologous blood transfusion, and cost associated with blood product usage after total knee arthroplasty (TKA). One hundred fifty-five patients with 177 consecutive TKAs over a 2-year period were studied. Group 1 patients had undergone unilateral TKA and did not predonate; 1A patients (n = 19) were drained with a Hemovac, and 1B patients (n = 28) with a postoperative blood recovery system. Group 2 patients (n = 47) predonated one packed red blood cell (pRBC) unit. Group 3 patients (n = 20) predonated 2 pRBC units. Group 4 patients had undergone bilateral sequential TKAs (n = 21) and had predonated 2 pRBC units. Group 5 patients (n = 14) had undergone revision TKA procedures and their blood requirements were individualized. Group 6 patients (n = 6) had preexisting anemia and were excluded from the study. There was no significant difference in total blood loss (909 mL) between groups. Female sex was associated with significantly lower admission hematocrit. Homologous blood was required for 4% of patients in the entire study and the percentage was not statistically different between groups. Twenty-five percent of patients who predonated autologous pRBCs did not use all or some of it. In group 1, the postoperative blood recovery system had a significant effect on reducing postoperative hematocrit drop (P = .0001), but it was not a significant factor if autologous pRBCs were available. The costs associated with group 1A were significantly less (P = .0001) compared with the other groups; group 1A had the highest admission hematocrit (43.2). Transfusion with autologous pRBCs was related to lower admission hematocrit rather than to increased postoperative blood loss. An algorithm is presented to provide cost-effective management of blood products after TKA.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Eastside Specialty Center, Redmond, Washington 98052, USA
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21
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Abstract
Our study examines the clinical, radiographic, and patient satisfaction outcome of the cemented Modular Porous-Coated Anatomic (PCA) total knee arthroplasty with a minimum 5-year follow up. All data were gathered prospectively and consecutively. Patient satisfaction was assessed with a self-administered survey. Statistical analysis examined the effect of 17 patient factors, 19 surgical factors, and postoperative continuous passive motion use on range of motion (ROM) and HSS scores at 2 years. Seventy-eight Modular PCA arthroplasties performed by 9 orthopedic surgeons on 71 patients between January 1988 and November 1989 are reported in this study. Preoperative HSS scores averaged 51.2 and improved to an average of 89 at 1 and 2 years, and 86 at 5 years after surgery (90% good or excellent). ROM changed after surgery through improvement in preoperative knee flexion contracture, but not in increased knee flexion. One patient underwent reoperation for patellar instability, and one patient's arthroplasty was revised at 53 months for late instability. The total reoperation rate for any reason was 7.7%. Zonal analysis for progressive radiolucency at the bone-cement interface showed increasing frequency of narrow (< 1 mm) radiolucencies concentrated on the anterior and medial aspect of the tibial tray. Ninety-eight percent of patients responded to an outcome questionnaire, and 96% rated themselves improved. The Kaplan-Meier probability of an implant surviving without loosening at 5 years was 100%. The Modular PCA TKA has a low incidence of patellofemoral problems, is clinically successful, and results are stable at a minimum 5-year follow-up examination.
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Affiliation(s)
- J L Knight
- Department of Orthopedics, Eastside Specialty Center, Redmond, WA 98052, USA
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22
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Knight JL, Au K, Whitley MA. Popliteal aneurysm presenting as chronic exertional compartment syndrome. Orthopedics 1997; 20:166-9. [PMID: 9048394 DOI: 10.3928/0147-7447-19970201-16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- J L Knight
- Department of Orthopedics, Group Health Cooperative of Puget Sound, Eastside Specialty Center, Redmond, WA 98052, USA
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23
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Abstract
Unicompartmental knee arthroplasty (UKA) is performed less frequently than total (tricompartmental) knee arthroplasty (TKA). This study examined the range of presenting symptoms and usefulness of diagnostic tests to determine the failure mode; the outcome of surgical revision of failed UKA is also reported. From a consecutive prospective series of 43 Porous Coated Anatomic (Howmedica, Rutherford, NJ) UKAs performed between 1985 and 1992 and followed for an average of 64 months, 12 cases have come to revision surgery (28%). The average time to failure was 37 months. Symptoms preceded revision surgery by an average of 10 months. The most common presenting symptom was pain (100%), followed by swelling (92%), reduced range of motion (42%), instability (42%), and clicking (17%). Failure was caused by polyethylene wear in 50%, loosening of the femoral component in 42%, and progression of patellofemoral arthritis in one patient. The combination of single leg standing anteroposterior radiographs and supine lateral radiographs detected most causes of UKA failure. A bone scan was confirmatory in every case of suspected loosening of the femoral component. Arthroscopy diagnosed polyethylene wear in two cases and progression of joint arthritis in one case and was not helpful in one case. Revision surgery was done with primary TKA components, and follow-up periods averaged 27 months. Bone stock deficiency was found in 58%, but required bone-grafting in only one case. Revision surgery successfully restored pain-free function and range of motion in all cases. Two-year postrevision Hospital for Special Surgery scores are equal to those for primary TKA. Survivorship analysis showed a 33% failure rate at 57 months after Porous Coated Anatomic UKA when revision was the endpoint and a 41% failure rate when unsatisfactory clinical status was the endpoint. Regular follow-up evaluation is suggested for the Porous Coated Anatomic UKA.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Eastside Specialty Center, Redmond, Washington 98052, USA
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24
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Knight JL, Gorai PA, Atwater RD, Grothaus L. Tibial polyethylene failure after primary porous-coated anatomic total knee arthroplasty. Aids to diagnosis and revision. J Arthroplasty 1995; 10:748-57. [PMID: 8749756 DOI: 10.1016/s0883-5403(05)80070-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Recognizing and providing effective treatment for polyethylene failure after total knee arthroplasty (TKA) are challenging problems. The range of presenting symptoms and the usefulness of diagnostic tests are examined, and the outcome of surgical treatment of patients with tibial polyethylene failure is reported. From a consecutive series of 209 Primary Porous-Coated Anatomic (Howmedica, Rutherford, NJ) TKAs performed between 1984 and 1987, 18 cases (9%) required revision surgery. No patient experienced polyethylene failure prior to 48 months, and the average time to revision was 81 months after index TKA. The follow-up period after revision surgery averaged 24 months. Symptoms began after a period of good function, and preceded revision by an average of 8 months. The most common presenting symptom was swelling (89%), followed by stiffness (72%), pain (67%), and clicking (38%) or instability (22%). Single leg standing anteroposterior radiographs were most effective, demonstrating polyethylene failure by a change to increasing varus and narrowing of the polyethylene space in 16 of 18 cases. Arthroscopic evaluation confirmed the diagnosis in two cases. Five cases required tibial tubercle osteotomy for exposure, and 15 required complete synovectomy. Exchange of the damaged heat-pressed polyethylene insert with a machined insert was performed in 14 cases, exchange plus tibial tray revision in 3 cases, and complete knee revision in 1 case. Revision surgery successfully restored pain-free function and improved range of motion in 16 of 18 cases. Survivorship analysis showed an 11% failure rate at 8 years after index procedure. Regular follow-up evaluation for the Primary Porous-Coated Anatomic TKA is suggested.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Redmond, Washington 98052, USA
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25
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Geiger-Dow JE, Knight JL, Sanfilippo AJ. Aortic ring abscess and mitral valve aneurysm in aortic valvular endocarditis: enhanced diagnosis with transesophageal echocardiography. Can J Cardiol 1995; 11:239-42. [PMID: 7889443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Aortic ring abscess and mitral valve aneurysms complicating infective endocarditis have previously been described as surgical or autopsy findings. More recently, transesophageal echocardiography has been shown to be more sensitive than standard transthoracic echocardiography or other imaging modalities in detecting each of these complications. Since aortic ring abscess and mitral valve aneurysms virtually mandate surgical intervention, their early detection may be crucial. This report describes a 35-year-old male with congenitally abnormal aortic valve which became infected and in whom both an aortic ring abscess and mitral valve aneurysm occurred. These findings are discussed and the pertinent literature is reviewed.
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Affiliation(s)
- J E Geiger-Dow
- Division of Cardiology and Cardiothoracic Surgery, Queen's University, Kingston, Ontario
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26
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Knight JL, Fujii K, Atwater R, Grothaus L. Bone-grafting for acetabular deficiency during primary and revision total hip arthroplasty. A radiographic and clinical analysis. J Arthroplasty 1993; 8:371-82. [PMID: 8409988 DOI: 10.1016/s0883-5403(06)80035-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The use of bone-graft to augment the deficient acetabulum in primary and revision total hip arthroplasty (THA) is controversial. To identify factors affecting cup loosening in patients who received a bone-graft during THA, two orthopaedic surgeons retrospectively examined sequential radiographs. The surgeons also obtained independent computer measurements of hip center and cup abduction migration from preoperative, initial, and latest postoperative radiographs. Variables studied included host factors, graft factors, and technique factors. All conclusions were based on Kaplan-Meier log-rank analysis to account for differing lengths of follow-up periods among the cases. The authors report a series of 74 consecutive cases with a minimum 24-month follow-up period (mean, 40 months). All grafts appeared to unite. The clinicians found 80% stable cups, 8% possibly loose cups, and 12% (n = 9) definitely loose cups. In retrospect, technical errors were seen in six loose cups. Five revisions for loosening (6.7% of cases) were performed. Computer measurement found cup loosening in a higher percentage of cases than detected by the clinicians and did so an average of 18 months sooner. Acetabular cup loosening was associated with the American Academy of Orthopaedic Surgeons type III defects, use of allograft versus autograft, and initial cup abduction of 50 degrees or more. Kaplan-Meier survivorship analysis found 31% of cups radiographically loose and 15% revised at 5 years or more since surgery. Acetabular bone-grafting is technically demanding and should be employed when alternative reconstructions will not give a durable result.
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Affiliation(s)
- J L Knight
- Department of Orthopaedic Surgery, Group Health Cooperative of Puget Sound, Redmond, WA 98052
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27
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McNamee CJ, Knight JL. Blunt traumatic avulsion of an intercostal artery: an unusual case of thoracic aortic injury. Can J Surg 1992; 35:658-60. [PMID: 1458395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The aortic isthmus is the most commonly injured part of the thoracic aorta in patients who survive blunt deceleration injury to that vessel long enough to reach a hospital. Occasionally, avulsion of the brachiocephalic arteries from the aortic arch is seen. The authors describe an unusual form of intrathoracic vascular injury in which mediastinal hemorrhage occurred secondary to avulsion of an intercostal artery from the descending thoracic aorta as a result of a vertical deceleration injury.
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Affiliation(s)
- C J McNamee
- Department of Cardiothoracic Surgery, Queen's University, Kingston, Ont
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McNamee CJ, Knight JL. Bronchogenic cyst masquerading as a chronic post-traumatic pseudoaneurysm of the aortic isthmus. Can J Surg 1992; 35:552-4. [PMID: 1393874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The serious nature of false aneurysms that develop in the aortic isthmus after blunt chest trauma is well known. The authors describe the case of a 33-year-old woman who presented with symptoms of chronic post-traumatic pseudoaneurysm of the aorta 3 months after blunt chest trauma. Radiologic investigations could not substantiate an aortic disruption. A bronchogenic cyst masquerading as a false aneurysm of the aorta was identified at thoracotomy. Bronchogenic cysts are one of the most common causes of primary mid-mediastinal masses and should be considered as potential causes of mid-mediastinal enlargement. However, this consideration should not delay urgent surgery if vascular damage cannot be ruled out.
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Affiliation(s)
- C J McNamee
- Department of Cardiothoracic Surgery, Queen's University, Kingston, Ont
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Welikovitch L, Knight JL, Burggraf GW, Sanfilippo AJ. Cardiac tamponade secondary to haemophilus pericarditis: a case report. Can J Cardiol 1992; 8:303-5. [PMID: 1576565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pyogenic pericarditis is encountered uncommonly in clinical practice. The majority of cases of clinically apparent pericarditis are viral in origin. When bacterial infection of the pericardial space does occur the causative organism is usually Staphylococcus or Streptococcus species. Isolation of an haemophilus organism from the pericardial space in this condition is distinctly unusual. There are only 10 previously reported cases in the literature of pericarditis secondary to Haemophilus influenzae. This report describes the case of a 36-year-old woman who presented with haemophilus empyema and purulent pericarditis progressing to cardiac tamponade. There are isolated reports of successful treatment of pyogenic pericarditis with closed drainage and antibiotics. In the absence of clear evidence demonstrating the efficacy of this approach the authors favour open exploration of the pericardial space.
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Affiliation(s)
- L Welikovitch
- Division of Cardiology, Queen's University, Kingston, Ontario
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30
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Abstract
This study evaluated the usefulness and accuracy of preoperative planning for cemented and cementless total hip arthroplasty (THA). The authors conducted a prospective study of 110 consecutive primary cases in which surgeons recorded the preoperative plan and what occurred in each case. Measured variables included estimated magnification, acetabular cup and femoral stem size, planned lengthening, and anticipated problems. Preoperative estimates of magnification frequently differed from actual magnification, and in 17% of cases it affected choice of implant size. Preoperative bone morphology did not correlate with type of femoral stem fixation. Implant sizing was predicted from the preoperative plan for 62% of acetabular cups, 78% of cemented stems, and 42% of the cementless stems. Leg-length equalization was a goal in only 70% of cases. Anticipated problems focused on anatomic variations, but intraoperative problems involved technique and equipment. The authors conclude that surgeons need better methods to estimate magnification and bone morphology from preoperative radiographs. Preoperative planning may not reduce intraoperative complications, which can arise from unanticipated technique and equipment mishaps.
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Affiliation(s)
- J L Knight
- Department of Orthopaedics, Group Health Cooperative of Puget Sound, Redmond, Washington 98052
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31
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Ryan G, Musk AW, Perera DM, Stock H, Knight JL, Hobbs MS. Risk factors for death in patients admitted to hospital with asthma: a follow-up study. Aust N Z J Med 1991; 21:681-5. [PMID: 1759915 DOI: 10.1111/j.1445-5994.1991.tb01370.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Hospital records of patients with asthma admitted to teaching hospitals in Perth, Western Australia between 1976 and 1980 were examined retrospectively to identify characteristics of the illness which were associated with subsequent death. From 5722 admissions there were 195 deaths to December 1982, 186 of whom had records available (cases); 452 of the surviving subjects were used for comparison (controls). There was no difference in age of onset of asthma or cigarette smoking habits between the two groups, but ischaemic heart disease as an associated condition was significantly more frequent in cases. On admission to hospital an arterial PCO2 less than 45 mmHg was more frequent in those who died, but there were no differences in arterial PO2, lowest pH, highest or lowest FEV1 and FVC. Cases more frequently used home nebulisers and were more frequently prescribed corticosteroids, antibiotics and sedatives or tranquilizers prior to admission, corticosteroids and sedatives or tranquilisers during admission and sedatives or tranquilisers on discharge. These results suggest that cases had more severe asthma in that they were more often treated with home nebulisers, corticosteroids and antibiotics, but with the exception of PaCO2 the commonly used measurements of severity of asthma did not identify those at risk of death. The prescription of sedatives or tranquillisers appears to be associated with an increased risk of death in subjects with asthma.
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Affiliation(s)
- G Ryan
- Department of Respiratory Medicine, Sir Charles Gairdner Hospital, Perth, WA
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32
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Knight JL. A precision guide-pin technique for wedge and rotatory osteotomy of the femur and tibia. Clin Orthop Relat Res 1991:248-55. [PMID: 1984924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Intraoperative guide-pin placement for the performance of wedge-type and rotatory osteotomy of the femur and tibia provides the desired angle of correction from single-leg, weight-bearing roentgenograms. A template is used as a guide for pin placement. The accuracy of this technique was evaluated by comparing the preoperative goal with the correction achieved immediately after surgery and after bone healing one year postoperatively. Forty-seven osteotomies, 37 in the tibia and ten in the femur, were reviewed. Eighty-five percent of the cases were within +/- 3 degrees of the operative goal immediately after surgery, and 81% one year postoperatively. Four osteotomies (9%) were considered failures, two because of technique and two because of errors in postoperative patient activity level. With appropriate preoperative planning, the technique makes accurate osteotomy possible in a standard operating room equipped with a C-arm fluoroscope.
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Affiliation(s)
- J L Knight
- Department of Orthopaedic Surgery, Group Health Co-operative of Puget Sound, Redmond, WA 98052
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Knight JL, Jacka M, Charrette EJ. Repair of isolated, symptomatic, sinus of Valsalva aneurysm in a patient with Marfan's syndrome. Can J Cardiol 1988; 4:214-6. [PMID: 3409102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A 29-year-old man with Marfan's syndrome presented with sudden onset of central chest pain radiating to the back. Aortography revealed a massively dilated right sinus of Valsalva aneurysm, with moderate aortic regurgitation. Urgent surgery in the form of a Bentall procedure was successfully carried out. There was no evidence of either aortic rupture or dissection. Acute expansion of the aneurysm must have precipitated the symptoms. The patient was alive and well three months later.
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Abstract
Left thoracotomy and femoro-femoral cardiopulmonary bypass has been used for reoperation in five patients requiring coronary bypass graft into the inferolateral surface of the heart. Five patients had refractory angina pectoris and angiographic occlusion of lateral wall native vessels or previous occluded vein grafts and all had positive exercise test. Four of the five had patent internal mammary to the LAD. Following supine positioning and removal of the saphenous vein and isolation of the femoral artery and femoral vein, a left fifth interspace thoracotomy was made, the patient heparinized and cannulated for cardiopulmonary bypass, the pericardium opened, the heart dissected free, and either the internal mammary artery dissected off the left chest wall or saphenous vein grafts used to bypass the appropriate lesions. The proximal inflow was the descending thoracic aorta making tunnels for the vein grafts through the posterior pericardium. All of the patients did well in the postoperative period. This technique is recommended for reoperations in patients with documented inferolateral ischemia as the primary cause of symptomatology with mitigating circumstances against an anterior approach.
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Affiliation(s)
- J L Knight
- Division of Cardiothoracic Surgery, Brigham and Women's Hospital, Boston, Massachusetts 02115
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Salvendy G, Knight JL. Circulatory responses to machine-paced and self-paced work: an industrial study. Ergonomics 1983; 26:713-717. [PMID: 6617636 DOI: 10.1080/00140138308963391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Salvendy G, McCabe GP, Sanders SG, Knight JL, McCormick EJ. Impact of personality and intelligence on job satisfaction of assembly line and bench work - an industrial study. Appl Ergon 1982; 13:293-299. [PMID: 15676456 DOI: 10.1016/0003-6870(82)90070-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A study of the impact of machine-paced (M/P) and self-paced (S/P) work on job satisfaction of 28 female industrial assembly workers was evaluated in which M/P work was confounded with simplified work and the S/P job was confounded with enriched tasks. Results indicated the following: 1. Over three-quarters of workers were more satisfied in S/P jobs, while only less than one-quarter were more satisfied in M/P jobs. 2. The 16PF personality test effectively predicts (0.88 multiple correlation) the satisfaction ratios of M/P to S/P jobs.
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Affiliation(s)
- G Salvendy
- Purdue University, West Lafayette, Indiana 47907, USA
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37
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Knight JL, Salvendy G, Geddes LA, Jans K, Smitt E. Monitoring the respiratory and heart rate of assembly-line factory workers. Med Biol Eng Comput 1980; 18:797-8. [PMID: 7230931 DOI: 10.1007/bf02441910] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Knight JL, Geddes LA, Salvendy G. Continuous, unobtrusive, performance and physiological monitoring of industrial workers. Ergonomics 1980; 23:501-506. [PMID: 7202396 DOI: 10.1080/00140138008924763] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Hickman K, Tortorici MP, Knight JL. How we operate a useful interdisciplinary teaching program for warfarin patients. Pharm Times 1980; 46:60-4. [PMID: 10246471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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40
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Knight JL, Ratcliffe SS, Weber JK, Hansen ST. Corrective osteotomy of femoral shaft malunion causing complete occlusion of the superficial femoral artery. J Bone Joint Surg Am 1980; 62:303-6. [PMID: 7358763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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41
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Weissman AM, Solomon DK, Baumgartner RP, Brady JA, Peterson JH, Knight JL. Computer support of pharmaceutical services for ambulatory patients. Am J Hosp Pharm 1976; 33:1171-5. [PMID: 998635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A prototype computerized pharmaceutical services support system (CPSSS) is described. CPSSS maintains records on approximately 40,000 patients; 1,300 outpatient prescriptions are dispensed per day. Using Univac hardware and software developed inhouse, CPSSS provides an online drug therapy profile. The prescription label, including auxiliary information, storage and stability guidelines as well as the traditional information, is automatically generated. Prior to medication dispensing, all information is verified by a pharmacist after the computer searches the patient medication profile for 5,400 potential drug-drug, 1,500 drug-disease state, over 100 drug-allergy and 200 drug-laboratory test interactions as well as identifying duplicate pharmacological therapy. Retrospectively, the patient population is described as to sex, age and number of diagnoses. The number of prescriptions per physician also is reported. Twenty drugs represent one-half of the total prescriptions, with 32% of patients taking diuretics and 30% taking tranquilizers. All new prescriptions were prospectively reviewed. Approximately 2% had potential interactions or pharmacological duplication of therapy problems. Approximately 30% of all new prescriptions duplicated exactly an active prescription on file. When a pharmacist initiated physician contact as a result of CPSSS and profile review, physicians changed therapy approximately 73% of the time when informed of duplicate therapy, 27% of the time when informed of potential drug-disease state interactions and 32% of the time when informed of potential drug-drug interactions.
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Knight JL, Hammond EK, Hauser LD, Baumgartner RP. Decentralized pharmacy technician training in a rural health care system. Am J Hosp Pharm 1974; 31:272-4. [PMID: 4819442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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45
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Pond HS, Bokat RB, Johnson JP, Knight JL, Healy GR, Gleason NN, Hall EC. Mass treatment for ascariasis: value of prophylactic use of piperazine in groups heavily infected with Ascaris lumbricoides. South Med J 1970; 63:599-602. [PMID: 5446832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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