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Gmelig Meyling C, Verschuren O, Rentinck ICM, Wright V, Gorter JW, Engelbert RH. Development of expert consensus to guide physical rehabilitation in children and adolescents with acquired brain injury during the subacute phase. J Rehabil Med 2023; 55:jrm12303. [PMID: 37584479 PMCID: PMC10448247 DOI: 10.2340/jrm.v55.12303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/05/2023] [Indexed: 08/17/2023] Open
Abstract
OBJECTIVE To develop consensus among experts to guide physical rehabilitation in children and adolescents with acquired brain injury during the subacute phase. DESIGN International Delphi study. METHODS A 3-round online Delphi study was conducted with 11 international experts in rehabilitation for children and adolescents with acquired brain injury. The first round consisted of open-ended questions; the second and third round consisted of ranking 139 statements on a 5-point Likert scale. RESULTS The panel reached consensus on 116/139 statements. Consensus was reached on the importance of age, pre-injury developmental stage and the clinical presentation of the child when determining content and focus of physical rehabilitation. In addition, consensus was reached on the importance of participation-focused interventions, and involvement of family members in goal-setting and therapeutic activities. Although dosage was deemed very important, no consensus was reached for determination of dose-response variables to suit and influence the child's needs. CONCLUSION This study provides a framework for clinicians to design physical rehabilitation interventions in children with acquired brain injury in the sub-acute recovery phase. The promotion of physical activity in meaningful contexts and involvement of family members are considered as important components to optimize recovery.
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Kim J, Dane C, Johnson C, Wright V. Robotic-assisted total laparoscopic hysterectomy in a patient with a history of a lefort colpocleisis: tips and tricks for performing a hysterectomy without a manipulator. Am J Obstet Gynecol 2023. [DOI: 10.1016/j.ajog.2022.12.226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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Kim J, Wang M, Wright V. Laparoscopic Repair of Post-Coital Vaginal Perforation Communicating with the Abdominal Cavity. J Minim Invasive Gynecol 2022. [DOI: 10.1016/j.jmig.2022.09.248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kim J, Jan A, Wright V. Low-Cost High-Fidelity Minimally Invasive Myomectomy Model for Laparoscopic and Robotic-Assisted Simulation. J Minim Invasive Gynecol 2022. [DOI: 10.1016/j.jmig.2022.09.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Moll T, Lott D, Wright V, Lien L, Subauste J. PMON89 Nephrogenic Diabetes Insipidus in a Patient on Temozolomide. J Endocr Soc 2022. [PMCID: PMC9627386 DOI: 10.1210/jendso/bvac150.1181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
A 54-year-old female admitted for nausea and vomiting found to have hypernatremia. Four months prior to this admission, patient had undergone emergent craniotomy for an intraparenchymal hemorrhage. Found to have a 7.8 cm hemorrhagic and partially necrotic mass. Pathology consistent with anaplastic oligodendroglioma. She began radiation and temozolomide 2 months after surgery. On this admission for nausea and vomiting, sodium noted to be elevated at 154 mmol/L (136-145 mmol/L). Initially thought to be due to dehydration and started on intravenous fluids. Urine output noted to increase to 2-3 liters/day with persistently elevated sodium. Urine studies and labs collected while sodium 155 mmol/L significant for urine osmolality 128 mOsm/kg (50-1200 mOsm/kg), serum osmolality 330 mOsm/kg (280-295), and urine sodium 34 mmol/L. Given patient's history of prior craniotomy, radiation, and temozolomide, suspected central diabetes insipidus but DDAVP challenge with 4 mcg did not result in a lower urine output and urine osmolality remained <300 mOsm/kg. Repeat DDAVP challenge produced similar results. Evaluation of other central axis deficiencies revealed normal Free T4 (1.21 ng/dL). Unable to assess for adrenal insufficiency due to patient already on high-dose steroids for malignancy. Workup was turned to potential nephrogenic etiology as patient had been started on pantoprazole during her initial diagnosis 4 months prior. Co-peptin while sodium 148 mmol/L returned at 27.6 pmol/L (<13.1 pmol/L), indicative for nephrogenic diabetes insipidus. Patient was started on amiloride 5 mg twice a day and hydrochlorothiazide 25 mg twice a day with improvement noted in both sodium and urine output. Did discuss renal biopsy to rule-out interstitial nephritis from pantoprazole but given patient was on anti-coagulation for sub-massive pulmonary embolism, biopsy was deferred. Ultimately patient was discharged on amiloride 10 mg and hydrochlorothiazide 25 mg daily with sodium 142 mmol/L. She continued to receive temozolomide but eventually both amiloride and hydrochlorothiazide were held during a subsequent admission about a month later due to hyponatremia from poor oral intake. Sodium remained stable for about 5 months off medication at which time patient was re-started on amiloride for hypernatremia. Unfortunately patient passed due to complications from thrombosis. Review of PubMed revealed only 1 additional case report of a patient on temozolomide who developed nephrogenic diabetes insipidus but that patient was also on sulfamethoxazole-trimethoprim which was most likely the cause. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.
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Ganz F, Wright V, Manns PJ, Pritchard L. Is Physical Activity-Related Self-Efficacy Associated with Moderate to Vigorous Physical Activity and Sedentary Behaviour among Ambulatory Children with Cerebral Palsy? Physiother Can 2021. [DOI: 10.3138/ptc-2020-0064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Purpose: To determine how physical activity-related self-efficacy is associated with physical activity and sedentary behaviour time among ambulatory children with cerebral palsy (CP). Method: Children with CP, Gross Motor Function Classification System (GMFCS) Levels I-III ( N = 26; aged 9–18 y), completed the task self-efficacy component of a self-efficacy scale and wore Actigraph GT3X+ accelerometers for 5 days. Correlations (Pearson and Spearman’s rank-order; a = 0.050) were conducted to evaluate the relationships among age, GMFCS level, self-efficacy, and both daily moderate-to-vigorous physical activity (MVPA) and sedentary time. Linear regression models were used to determine the relationships among the independent variables and MVPA and sedentary time. Results: Self-efficacy was positively associated with MVPA time ( r = 0.428, p = 0.015) and negatively correlated with sedentary time ( r = –0.332, p = 0.049). In our linear regression models, gross motor function (β = –0.462, p = 0.006), age (β = –0.344, p = 0.033), and self-efficacy (β = 0.281, p = 0.080) were associated with MVPA time ( R2 = 0.508), while GMFCS level (β = 0.439, p = 0.003) and age (β = 0.605, p < 0.001) were associated with sedentary time ( R2 = 0.584). Conclusions: This research suggests that self-efficacy, age, and gross motor function are associated with MVPA in children with CP. Additional research is needed to confirm these findings and further explore the influence of self-efficacy on sedentary behaviour.
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Dauterive E, Wright V. Bone Breaking Triglycerides. J Endocr Soc 2021. [PMCID: PMC8089626 DOI: 10.1210/jendso/bvab048.626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A 40 yo African American female with pmhx of T2DM, DLD was admitted for worsening leg and arm pain that started a year prior but had worsened in the last 6 months. Pain started in the right arm and progressed to include the right leg and left leg. She had presented to the ER 3 times in the last 3 weeks with no diagnosis and prescribed anti-inflammatories. On ROS she had unintended weight loss of 50 lbs. Pain was not relieved with anti-inflammatories or narcotics. She was diagnosed with diabetes in the previous 5 years and had not been compliant with her medications. Plain x-rays showed OA of the hip. An osseus survey showed multiple expansile, bubbly, and lucent intramedullary lesions consistent with polyostotic fibrous dysplasia versus multiple myeloma. CT showed a radiolucent lesion of the left femur with absence of normal bone trabeculae. Her labs showed normal calcium, phosphorous, renal function, PTH and no evidence of monoclonal gammopathy. Vitamin D was low at 8.2 ng/ml (6.6–49 ng/ml). CT CAP showed no concern for malignancy in other organs. A lipid profile was done and showed elevated fasting triglycerides of 2617 mg/dL (<150 mg/dl) and LDL direct 54 mg/dl (<100 mg/dl). A1c was 11.2% on admission. She denied any use of alcohol, estrogens, SSRI’s. No history of pancreatitis. On physical exam she did not have tendinous xanthomas, eruptive xanthomas, palmar xanthomas, or lipemia retinalis. Family history not significant for lipid disorders. Patient was fasted for 24 hours and then started on intensive insulin regimen as well as fenofibrate for hypertriglyceridemia. Triglycerides came down to less than 500 over 7 days. She was evaluated by ortho for her bone lesions and underwent bone lesion biopsy as well as prophylactic IMN of her bilateral femurs for prevention of impending fragility fractures. Bone biopsy was significant for xanthoma of the bone. Following discharge, she remained on fenofibrate and fish oil as well as a basal/bolus insulin regimen. Triglycerides remained controlled. She has not followed up outpatient for further workup. This case highlights an atypical presentation of triglyceride deposition in the setting of hypertriglyceridemia. It shows that hypertriglyceridemia should be included in the differential for lytic lesions when preliminary workup is negative. It also highlights that complications other than pancreatitis and cardiovascular disease can significantly alter a patient’s life if triglycerides go untreated.
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Watson G, Wright V, Long S, De L'Aune W. A Low Vision Reading Comprehension Test. JOURNAL OF VISUAL IMPAIRMENT & BLINDNESS 2020. [DOI: 10.1177/0145482x9609000606] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Low Vision Reading Comprehension Assessment (LVRCA) uses an 18-sentence cloze format in two equivalent forms to measure understanding of print reading by persons with macular degeneration. It requires nine minutes to administer and thus can be used in clinical settings. This article describes its development and a study of the reliability and validity of the LVRCA tested on 50 persons with macular degeneration.
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Watson G, Wright V, de L'Aune W. The Efficacy of Comprehension Training and Reading Practice for Print Readers with Macular Loss. JOURNAL OF VISUAL IMPAIRMENT & BLINDNESS 2020. [DOI: 10.1177/0145482x9208600118] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The objectives of the project reported here were to discover whether the rehabilitation of reading recognition allows comprehension of print for low vision individuals who were former readers and to develop and test training strategies for enhancing comprehension for those who do not achieve good comprehension.
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Marsden J, Anders P, Clark H, Colocassis K, Eastwood B, Knight J, Melaugh A, Quinn D, Wright V, Stannard J. Protocol for a multi-centre, definitive randomised controlled trial of the effectiveness of Individual Placement and Support for employment support among people with alcohol and drug dependence. Trials 2020; 21:167. [PMID: 32046765 PMCID: PMC7014654 DOI: 10.1186/s13063-020-4099-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 01/21/2020] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Unemployment is highly prevalent in populations with alcohol and drug dependence and the employment support offered in addiction-treatment programmes is ineffective. Individual Placement and Support (IPS) is an evidence-based intervention for competitive employment. IPS has been extensively studied in severe mental illness and physical disabilities, but there have been no formal randomised controlled trials (RCTs) in alcohol and drug dependence. The Individual Placement and Support for Alcohol and Drug Dependence (IPS-AD) study should determine whether IPS for patients with alcohol use disorder (AUD), opioid use disorder (OUD) and other drug use disorder is effective. DESIGN/METHODS The IPS-AD study is a seven-site, pragmatic, two-arm, parallel-group, superiority RCT. IPS-AD includes a realist process evaluation. Eligible patients (adult, unemployed or economically inactive for at least 6 months and wishing to obtain open job market employment and enrolled in ongoing community treatment-as-usual (TAU; the control condition) in England for AUD, OUD and other drug use disorders) will be randomised (1:1) to receive TAU and any standard employment support, or TAU plus IPS (the experimental condition) for 9 months with up to 4 months of in-work support. The primary outcome measure will be competitive employment status (at least 1 day (7 h)) during an 18-month follow-up, determined by patient-level, trial-data-linkage with national tax and state benefit databases. From meta-analysis, an 18% target difference on this measure of vocational effectiveness (for the experimental intervention) and a two-sided 5% level of statistical significance, will require a minimum target sample of 832 participants to achieve 90% power for a pre-registered, mixed-effects, multi-variable logistic regression model. A maximum-likelihood multiple-imputation approach will manage missing outcome data. IPS-AD has six vocational secondary outcome measures during the 18-month follow-up: (1) total time in competitive employment (and corresponding National Insurance contributions and tax paid); (2) time from randomisation to first competitive employment; (3) number of competitive job appointments; (4) job tenure (length of longest held competitive employment); (5) sustained employment (tenure in a single appointment for at least 13 weeks); and (6) job search self-efficacy. A primary cost-benefit analysis and a secondary cost-effectiveness analysis will be done using the primary outcome and secondary vocational outcomes, respectively and will include addiction treatment and social and health outcomes and their associated reference costs. The process evaluation will address IPS implementation and delivery. DISCUSSION The IPS-AD study is the first large-scale, multi-site, definitive, superiority RCT of IPS for people with alcohol and drug dependence. Findings from the study will have substantial implications for service delivery. TRIAL REGISTRATION ISRCTN Registry, ID: ISRCTN24159790. Registered on 1 February 2018.
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Matthews BJ, Jan A, Wright V. 2968 A Combination of Robotic-Assisted Excision and CO2 Laser Ablation for the Treatment of Superficial Diaphragmatic Endometriosis. J Minim Invasive Gynecol 2019. [DOI: 10.1016/j.jmig.2019.09.316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Wright V, Subauste A. SUN-326 Hypoglycemia and Lactic Acidosis: The Deadly Signs of Untreated Non-Hodgkin's Lymphoma. J Endocr Soc 2019. [PMCID: PMC6553231 DOI: 10.1210/js.2019-sun-326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Introduction The presentation of hypoglycemia with lactic acidosis is rare, though well-described. It is most commonly associated with hematologic malignancies and is attributed to the Warburg effect in which cells consume large amounts of glucose through the glycolytic pathway with lactic acid production, even in aerobic conditions. Clinical Case 64yo WM with cirrhosis due to hemochromatosis, atrial fibrillation, type 2 diabetes mellitus managed by diet, initially presented with weakness, malaise and thrombocytopenia. Imaging revealed splenomegaly, bilateral adrenal masses, and diffuse lymphadenopathy. He was admitted, given IV fluid hydration, and discharged to have outpatient lymph node biopsy. Prior to biopsy he developed worsening weakness, fatigue, shortness of breath, and hypoxia. Lactate was 8.1mmol/L, n=0.7-2.1. He was admitted for sepsis secondary to pneumonia. During hospitalization, he was noted to be hypoglycemic (serum glucose 40mg/dL), requiring continuous dextrose infusion and dextrose 50% boluses. Evaluation was consistent with insulin independent hypoglycemia with labs as follows: Insulin <1 microU/mL (2-25), c-peptide 0.65ng/mL (0.78-5.19), proinsulin 4.2pmol/L (3.6-22), beta-hydroxybutyrate 4.07mg/dL (0.2-2.8), glucose 49mg/dL then 44mg/dL 30 minutes after administration of glucagon. ACTH 8.1pg/mL (7.2-63) and cortisol 11mcg/dL then 14.8mcg/dL after cosyntropin stimulation. He was started on stress dose steroids. Lactic acidosis persisted and worsened (>15mmol/L). Repeat CT imaging was obtained to search for potential source of lactic acidosis, though none was found. It was later noted that increasing lactate levels occurred with increased dextrose administration. A perirenal lymph node biopsy was performed. Shortly after the procedure, the patient rapidly decompensated. He was started on continuous renal replacement therapy and given rasburicase for suspected tumor lysis syndrome. Despite these efforts, the patient died. Pathology later returned positive for Non-Hodgkin’s Lymphoma. Discussion In this case, hypoglycemia was initially confounded by a history of cirrhosis and possible adrenal insufficiency. However, no improvement with steroids and worsening of lactic acidosis with increasing dextrose administration demonstrated that hypoglycemia was due to the Warburg effect in the setting of undiagnosed Non-Hodgkin’s Lymphoma. Recognizing this phenomenon is imperative as it coincides with high mortality, and the treatment of underlying disease may be the only effective option. References Georges C. Elhomsy, et al; “Hyper-Warburgism,” a Cause of Asymptomatic Hypoglycemia with Lactic Acidosis in a Patient with Non-Hodgkin's Lymphoma, The Journal of Clinical Endocrinology & Metabolism, Volume 97, Issue 12, 1 December 2012, Pages 4311-4316.
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Morales L, Griffith G, Wright V, Fleming E, Umberger W, Hoang N. Branding fresh food: Who is willing to pay more for beef? ACTA ALIMENTARIA 2017. [DOI: 10.1556/066.2016.0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Medley JB, Dowson D, Wright V. Transient Elastohydrodynamic Lubrication Models for the Human Ankle Joint. ACTA ACUST UNITED AC 2016; 13:137-51. [PMID: 6542885 DOI: 10.1243/emed_jour_1984_013_035_02] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An equivalent bearing was proposed to represent the normal human ankle joint. The geometry was based on measurements of dissected ankle joints and tissue properties were obtained from the work of previous investigators. Theoretical models were developed to estimate the cyclic variation in lubricant film thickness and coefficient of friction during repetitive activities such as walking. Solutions were obtained for various combinations of input parameters. For the conditions representing the walking cycle, film thicknesses of about 0.7 μm were calculated. Although this value was smaller than most previous measurements of the rms roughness of cartilage, it was not much smaller and suggested that transient elastohydrodynamic lubrication played a role in synovial joint lubrication. The possibility of full fluid film lubrication was supported only when a very high input viscosity was employed, based on values estimated from the previous experimental studies of the boosted lubrication mechanism. Also, an attempt was made to link the current findings to a published experimental study of whole joint lubrication.
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Amis AA, Dowson D, Unsworth A, Miller JH, Wright V. An Examination of the Elbow Articulation with Particular Reference to Variation of the Carrying Angle. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1977_006_021_02] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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O'Kelly J, Unsworth A, Dowson D, Hall DA, Wright V. A Study of the Role of Synovial Fluid and its Constituents in the Friction and Lubrication of Human Hip Joints. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1978_007_022_02] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Human hip joints have been studied in a pendulum apparatus and a joint simulator to determine the lubrication mechanisms active in normal physiological activities. Various lubricants have been used to lubricate the hip joints including bovine and human synovial fluid, synovial fluid which has been digested with hyaluronidase or trypsin, silicone fluids of different viscosities, as well as synovial fluid and Ringer's solution which have had their viscosities increased by the addition of hyaluronic acid. The results indicate that under continuous dynamic loading, fluid film lubrication seems to prevail while under static loading, mixed lubrication exists. Increasing the viscosity of the lubricant from very low values (i.e. from 10-3 Pa.s) leads to a reduction in friction, indicating mixed lubrication, until a value of about 0.050 Pa.s was achieved. Further increases seemed to indicate that fluid film lubrication was then present.
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Jobbins B, Bird HA, Wright V. A Finger Arthrograph for the Quantification of Joint Stiffness. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1981_010_025_02] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Jobbins B, Bird HA, Wright V. A Joint Hyperextensometer for the Quantification of Joint Laxity. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1979_008_024_02] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Amis AA, Miller JH, Dowson D, Wright V. Biomechanical Aspects of the Elbow: Joint Forces Related to Prosthesis Design. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1981_010_021_02] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Cooke AF, Dowson D, Wright V. The Rheology of Synovial Fluid and Some Potential Synthetic Lubricants for Degenerate Synovial Joints. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1978_007_021_02] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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O'Kelly J, Unsworth A, Dowson D, Wright V. An Experimental Study of Friction and Lubrication in Hip Prostheses. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1979_008_040_02] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
McKee-Farrar, Charnley and Muller prostheses have been studied in a hip function simulator using a range of silicone fluids as lubricants. Frictional resistance was measured continuously while the joints were subjected to dynamic loading. It was observed that the lubricant viscosity was very important to the mode of lubrication prevailing and that for viscosities in excess of 0.1 Pas, full fluid film lubrication was achieved. At viscosities which were less than this, mixed lubrication resulted These results can be extrapolated to the clinical situation where it was found that after hip surgery for total joint replacement, the synovial fluid produced around the prosthesis had a viscosity which was less than 0.1 Pas, and therefore could not give the most advantageous lubrication in these joints in vivo.
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Abstract
A survey of past literature has shown that there is a lack of reliable data for use in prediction of joint forces in the upper limb although this is desirable when developing joint replacements. Upper limb geometry has been analysed, leading to muscle moment arm data at the wrist and elbow. The variation of these moment arms during elbow flexion has also been examined. Analysis of the dimensions of muscles has enabled their relative strengths to be predicted, based on their ‘physiological cross-sections’. When used in conjuction with published emg data, this information will enable elbow and wrist joint forces to be estimated more realistically than has previously been possible.
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Ellis MI, Seedhom BB, Wright V, Dowson D. An Evaluation of the Ratio between the Tensions along the Quadriceps Tendon and the Patellar Ligament. ACTA ACUST UNITED AC 2016. [DOI: 10.1243/emed_jour_1980_009_049_02] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An experiment was devised whereby physiological loads could be applied to the quadriceps tendon of cadaveric knee joints so that the ratio of tensions in the quadriceps tendon and the patellar ligament could be determined. On two knee joints, radiographs were taken before testing, so that the theoretical ratio of the tensions could be evaluated and compared with the experimental results. As the knee was flexed, the ratio of the tensions, frequently assumed to be unity, reduced by up to fifty per cent.
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