Imperial College London

Professor Hippolite Amadi, PhD FRSM

Faculty of EngineeringDepartment of Bioengineering

Visiting Professor
 
 
 
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Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Publication Type
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62 results found

Amadi HO, Abdullahi RA, Mokuolu OA, Ezeanosike OB, Adesina CT, Mohammed IL, Olateju EK, Abubakar AL, Bello MA, Eneh AU, Ogah EO, Eziechila BC, Chapp-Jumbo AU, Jimoh A, Udo JJet al., 2019, Comparative outcome of overhead and total body phototherapy for treatment of severe neonatal jaundice in Nigeria, PAEDIATRICS AND INTERNATIONAL CHILD HEALTH, Vol: 40, Pages: 16-24, ISSN: 2046-9047

Journal article

Amadi H, Abubakar AG, Abubakar AL, Usuf H, Usman Met al., 2019, Hypothesis of Iatrogenic Severe Hypothermia of Internal Organs in Extremely-Low Birthweight Infants during Bubble CPAP Intervention at Room-temperatures in Nigeria, EC Paediatrics, Vol: 8, Pages: 517-524

Background: Bubble continuous positive airway pressure (CPAP) application has become popular in Nigeria against the backdrop of very high incidence of respiratory distress syndrome among preterm neonates in the country. An estimated > 90% of interven-tions in Nigeria is carried out via an improvised technique or use of devices that deliver CPAP gas at room temperatures only. There is however, a high record of neonatal mortality amongst very- and extremely-low birthweight neonates that receive CPAP treatments using these devices. It is suspected that a possible dodgy severe hypothermia could be blamed; hence the need for a preliminary hypothesis.Methods:The aetiology of CPAP iatrogenic hypothermia was studied via free-body modelling to formulate prevailing thermal in-terplay. Thirteen extremely-low birthweight neonates (BW: 600g - 1000g) were recruited to test the hypothesis. Four of these were treated with CPAP-temperature-controlled device, whereas the rest of the 13 were treated with disposable improvised CPAP devices that delivered air at room temperatures. A digital thermometer probe was inserted in the CPAPs’ gas delivery tubes to measure the temperatures of the inspiratory gas just before the infant received this.Results: Only four of the extremely-low birthweight infants were successfully weaned from the CPAP interventions. All four received pre-warmed CPAP gas but all nine unsuccessful infants received CPAP gas at room temperature. All 13 patients maintained physiolog-ical temperatures > 36.5°C, measured superficially via the axilla. Median inspiratory gas temperatures for all the deceased remained below 32°C throughout, whereas those of the successful infants remained above 35.5°C. Conclusion: Acceptable axillary temperatures may be concealing dangerous internal iatrogenic hypothermia, perhaps at the lungs leading to organ failures and death. Internal organ temperatures below 33°C may be insuff

Journal article

Amadi HO, Okonkwod IR, Abioye IO, Abubakar AL, Olateju EK, Adesina CT, Umar S, Eziechila BCet al., 2019, A new low-cost commercial bubble CPAP (bCPAP) machine compared with a traditional bCPAP device in Nigeria, PAEDIATRICS AND INTERNATIONAL CHILD HEALTH, Vol: 39, Pages: 184-192, ISSN: 2046-9047

Journal article

Amadi HO, Kawuwa MB, 2017, Reducing Early Neonatal Mortality in Nigeria – the Solution, Neonatal care, Editors: Mauricio, ISBN: 978-953-51-5331-3

Book chapter

Amadi HO, Olateju EK, Adeshina CT, Kawuwa MB, Lawal MIet al., 2017, HISA-protocol for lowering neonatal mortality – a tool Nigeria can’t afford to ignore, 10th National conference, Nigerian society of neonatal medicine

Conference paper

Amadi HO, Olateju EK, Adeshina CT, 2017, Temperature control that minimises early neonatal deaths, proceedings of the 3rd Global Forum on medical devices, World Health Organisation

Conference paper

Amadi HO, Adesina CT, Olateju EK, Omokaro S, Okechukwu AA, Alabi P, Haruna ASet al., 2017, Validation of a Novel Technique that Minimises Early Neonatal Deaths - a Comparative Study, Journal of Pediatrics & Neonatal Care, Vol: 6

Nigeria did not achieve the millennium development goal (MDG) for the reductionof under-5 mortality (U5M) in 2015. Neonatal death still accounts for nearly 50%of U5M, hence responsible for this failure. The World Health Organisation recordsshowed that 79% of deceased neonates would die within the first-seven-days(F7D) of life in Nigeria. Prolonged postnatal delay before attainment of normalbody temperature could be partly responsible. Reducing F7D deaths could improveNigeria’s overall record; hence the urgent need to device a technique that couldbe applied to achieve this. We developed a neonatal temperature control protocol“the initial-setpoint-algorithm (ISA)” as a response to temperature-related highF7D mortality rate. A total 134 cases (105 controls and 29 tests) were recruited.The cases drew from extremely- low birth weight and preterm neonates (BW =600-1200 g, GA = 26-32 weeks) presenting at the University of Abuja TeachingHospital Nigeria. Mortality outcomes were compared to investigate how theISA group performed relative to the Control group. Applying ISA, Test-patientsattained normotherm in 0.47 hr post-presenting (95%CI: 0.2); Control took 12.4hrs (95%CI: 2.3). The F7D-deaths contribution to mortality in the control groupwas 71% (41 out of 58). There was no F7D death amongst the only two deceasedneonates in the test group. The ISA helped quick attainment of normotherm in theTest-group; hence removed the immediate postnatal long exposure to damagingthermal shock that trailed other neonates to death within the F7D period.

Journal article

Amadi HO, Olateju EK, Alabi P, Kawuwa MB, Ibadin MO, Osibogun AOet al., 2015, Neonatal hyperthermia and thermal stress in low- and middle-income countries: a hidden cause of death in extremely low-birthweight neonates, PAEDIATRICS AND INTERNATIONAL CHILD HEALTH, Vol: 35, Pages: 273-281, ISSN: 2046-9047

Journal article

Olutunde OE, Oyedokun A, Olateju EK, Ibekwe MU, Kawuwa MB, Alabi P, Amadi HOet al., 2015, EXTREME LOW BIRTH PARAMETER NEONATES WOULD MORE READILY DIE OF HYPERTHERMIA THAN HYPOTHERMIA IN NIGERIA, Paediatrics Association of Nigeria Conference (PANCONF)

Objective: To investigate how thermal instability might have contributed to a record high neonatal mortality of extreme low birth weight (ELBW) babies in Nigeria.Methods: Ninety-two previous cases from three Nigerian tertiary hospitals were analysed. The average birth weight of the sample population was 993g ± 256g; range: 600g to 1500g from which the ELBW cases (mean: 846g ± 128g; range: 600g to 1000g) were isolated. A temperature-time graph with clearly visible thermal safe-zone band was developed from which all fatality-associated thermal instabilities were identified and defined based on their characteristic consistencies. Parametric quantifications for these were devised to enable the definition of critical values. This was applied to all cases in the sample population to identify and quantify a measure of the various thermal distresses that might have contributed or led to neonatal death. Algorithm-based thermal control technique was devised and results from surviving cases compared.Findings: Hypothermic complications were prevalent with a fatality rate of 22.7% and associated with 65% of all deaths. Hyperthermic related complications accounted for 35% of all deaths but with a higher fatality rate of 64.3%. All babies that experienced prolonged hypothermia that culminated in a sharp flip to hyperthermia survived. However all those that experienced prolonged hyperthermia culminating in a sharp flip to hypothermia died within 12 hours of the event. Algorithm-based patients did not experience this flip.Conclusion: Hyperthermia will more readily kill neonates; hence methods of quenching high and prolonged fever must be reviewed.

Conference paper

Amadi HO, 2014, High rate of neonatal morbidity and mortality due to climate-related diseases, WHO conference on health and climate, Publisher: International Institute for Sustainable Development, Pages: 6-6

Conference paper

Amadi HO, Osibogun AO, Eyinade O, Kawuwa MB, Uwakwem AC, Ibekwe MU, Alabi P, Ezeaka C, Eleshin DG, Ibadin MOet al., 2014, Challenges and frugal remedies for lowering facility based neonatal mortality and morbidity: a comparative study., Int J Pediatr, Vol: 2014, Pages: 986716-986716, ISSN: 1687-9740

Millennium development goal target on infant mortality (MDG4) by 2015 would not be realised in some low-resource countries. This was in part due to unsustainable high-tech ideas that have been poorly executed. Prudent but high impact techniques could have been synthesised in these countries. A collaborative outreach was initiated to devise frugal measures that could reduce neonatal deaths in Nigeria. Prevailing issues of concern that could militate against neonatal survival within care centres were identified and remedies were proffered. These included application of (i) recycled incubator technology (RIT) as a measure of providing affordable incubator sufficiency, (ii) facility-based research groups, (iii) elective training courses for clinicians/nurses, (iv) independent local artisans on spare parts production, (v) power-banking and apnoea-monitoring schemes, and (v) 1/2 yearly failure-preventive maintenance and auditing system. Through a retrospective data analyses 4 outreach centres and one "control" were assessed. Average neonatal mortality of centres reduced from 254/1000 to 114/1000 whilst control remained at 250/1000. There was higher relative influx of incubator-dependent-neonates at outreach centres. It was found that 43% of mortality occurred within 48 hours of presentation (d48) and up to 92% of d48 were of very-low birth parameters. The RIT and associated concerns remedies have demonstrated the vital signs of efficiency that would have guaranteed MDG4 neonatal component in Nigeria.

Journal article

Amadi HO, Emery RJ, Wallace A, Bull Aet al., 2014, Specificity of clinical examinations for testing glenohumeral ligament integrity: a computational study, Computer Methods in Biomechanics and Biomedical Engineering, Vol: 17, Pages: 933-943, ISSN: 1025-5842

An accurate diagnosis of glenohumeral joint (GHJ) instability is essential for an effective surgical intervention. There is presently no known comprehensive algorithm of clinical tests for the confirmation of the functional integrity of glenohumeral ligaments (GHLs). A validated computational GHL strain analyser was applied to a set of GHJ kinematics data from the literature to simulate 57 different physiological clinical examination manoeuvres. An algorithm that integrates the GHL pre-straining activities at the toe region of the stress–strain curve was developed for the quantification of ligament loading from prevailing strains. This was used to upgrade the strain analyser and applied to produce a matrix of the various GHL loadings and sensitivities during the manoeuvres. The investigation magnified the likely impact of anatomical variations of GHL attachments as possible causes of misdiagnoses during clinical examinations of GHJ dysfunction. This can serve as an assistive guide to ascertain the functional condition of a specific GHL during symptomatic clinical examinations.

Journal article

Amadi HO, Mohammed LI, Kawuwa MB, Oyedokun A, Mohammed Het al., 2014, Synthesis and Validation of a Weatherproof Nursery DesignThat Eliminates Tropical Evening-Fever Syndrome in Neonates, International Journal of pediatrics, Vol: 2014, ISSN: 1687-9740

Neonatal thermal stabilisation can become challenging when uncontrollable factors result in excessive body temperature.Hyperthermia can rapidly slow down baby’s progress and response to treatment. High sunlight intensity in tropical countriessuch as Nigeria manifests in incessant high neonatal temperatures towards early evenings.The ugly consequences of this neonatalevening-fever syndrome (EFS) can only be eradicated by the development of a controlled weatherproof nursery environment. Twolaboratories and a ‘control ward’ were applied. Lab-2 was a renovation of an existing room in a manner that could correct anexisting nursery. Lab-1 was an entirely new building idea. The laboratories were assessed based on comparative ability to maintainenvironmental coolness and neonatal thermal stability during hot days. Data collection continued for 12 full calendar months. Onaverage, at evaluated out-wind peak temperature of 43∘C (range: 41∘C–46∘C), the control-ward peak was at 39∘C, Lab-2 peak at36∘C, and Lab-1 peak at 33∘C. All incubators in the control overheated during the hot periods but there was no overheating inLab-1. Forty-four (86%) of sampled babies were fever-quenched by water sponging 131 times in the control whilst only one babyreceived same treatment in Lab-1. Nursery designs patterned after Lab-1 can significantly reduce EFS-induced neonatal morbidity.

Journal article

Amadi HO, Alabi P, Uwakwem AC, 2014, Neonatal Concerns – a collaborative medical outreach for newborn babies in tropical sub-Saharan Africa, Paediatrics Association of Nigeria Conference

The Millennium Development Goal no.4 (MDG4) targets two-third reduction in under-5-years (U5) mortality rate between 1990 and 2015. Since neonatal mortality owns 40% of U5 deaths, any measures undertaken to improve newborn care would make steps towards MDG4 target. For 12 years of MDG4 pursuit, none of the steps undertaken by Agencies and the Nigerian government was able to demonstrate significant signs of more newborn survival going by the timeline between Ibe’s (1993) increasing-admission-delivery and Ogunlesi et al’s (2008) worsening point-of-admission-hypothermia. Very poor neonatal transport to care-centres caused nearly 100% of all premature babies to arrive hypothermic. Nearly full term neonates might scarcely survive with KMC technique, however extreme-low-birth-weight (<1500g) and extremely-preterm (<31-weeks-GA) neonates would die without adequate incubator intervention. A standard Nigerian newborn centre could have up to 45 neonates on admission of which 20 or more would be struggling preterm babies. Such situation demands for over 20 units of functional incubators to be available in such centres at any time if these babies must survive. However most Nigerian centres could not demonstrate a consistent availability of up to 4 functional incubators over a period of any two years. Incubators were unaffordable and technically sophisticated; therefore a low-cost culturally compliant incubator model and procedures must be developed to tackle this fundamental failure for MDG4 to succeed.Research and development outreach was initiated to: (i) devise the Recycled Incubator Technology (RIT), capable of up to 10 years incubator life expectancy. A cumulative 20 Nigerian newborn-centres were recruited and progressively expanded in functional incubator capacity using RIT systems. (ii) Set up facility-based research groups. (iii) Develop two elective training courses for clinicians/nurses. (iv) Training independent artisans on spare parts production. (

Conference paper

Amadi HO, Kawuwa MB, Mohammed IL, Oyedokun A, Muhammad Het al., 2013, Eradication of climate-induced neonatal hyperthermia through nursery building design, World Health Organisation (WHO) 2nd Global Forum on Medical Devices

Daytime ambient temperatures of tropical climates can rapidly rise in excess of 43°C, overheating any exposed objects. This leads to the over-warming of neonatal nurseries, occupant baby temperatures soaring up to hyperthermic 40°C during early evenings of sunny days. Unaware of this neonatal ‘evening fever syndrome (EFS)’, clinicians have responded with doses of antibiotics mistaking this as infection sign. Others combined their desperate measures with ‘water-sponging’ of babies above 37.9°C. Thermoneutral instability increases morbidity and slows down progress. Unnecessary antibiotic treatment complicates situations and could kill such baby. Climate-induced hyperthermia could be eliminated if nurseries were appropriately sited and designed to guarantee natural coolness. This will allow better neonatal thermoneutral regulation through incubators.Federal Medical Centre Nguru gave Ethical Approval and hosted this research. Two laboratories of building constructs were erected, each double-walled having in-between air space for lagging. Lab-1 was new building with underground floor and heat-exchanger. Lab-2 was an existing room renovated for existing nursery correction. The laboratories were assessed on ability to maintain environmental coolness and incubator/neonatal thermal stability during extreme-hot days as compared to the hospital’s main nursery, ‘Control-ward’. Data collection continued for 24 months, constructions validated and extreme-hot months of February-May and August-October data extracted and analysed.Average peak-temperature of outside-wind was 43°C (range: 41°C–46°C); Control-ward was 39°C, Lab-2 (36°C) and Lab-1 (33°C). All incubators in Control overheated during the temperature-high periods of the day but there was no incubator overheating in Lab-1. There were 131 water-sponging events for fever-quenching on Forty-four (86%) of sampled babies in the Control-ward. Only

Conference paper

Amadi HO, Azubuike JC, Adimora GN, Osibogun AO, Alabi P, Uwakwem ACet al., 2013, Unexplored success route to Nigeria’s MDG4 target on neonatal mortality, World Health Organisation 2nd Global Forum on Medical Devices

MDG4 targets two-third reduction in under-5-mortality rate (U5MR) by 2015. Since neonatal mortality accounts 40% of U5MR in Nigeria, any measure undertaken to improve newborn care contributes towards MDG4 target. Many years into MDG4 pursuit, Nigeria could not demonstrate significant progress in newborn survival, from Ibe’s (1993) ‘increasing-admission-delivery’ report to Ogunlesi et al’s (2008) ‘worsening-hypothermia-risks’. Inadequate neonatal transport to care-centres made premature babies arrive hypothermic. Extreme-low-birth-weight (<1500g) and extremely-preterm (<31weeks-GA) neonates would die without incubator care. A typical Nigerian newborn-centre could have 45 neonates on admission, of which 30 could be preterm. Such situation requires over 20 units functional incubators if the babies must survive. However, no Nigerian centre could demonstrate consistent availability of 4 functional incubators over a period of two years. Incubators were unaffordable and sophisticated, hence low-cost culturally-compliant models must be developed to tackle this fundamental deficiency for MDG4 to succeed.Outreach was initiated (2003) to: (i) devise the Recycled-Incubator-Technique (RIT), which applies generic components to convert carcasses into low-cost incubators, capable of 10 years of life. A cumulative 20 hospital newborn-centres were recruited and progressively expanded in incubator capacity using RIT-systems. (ii) Create centre-based research groups. (iii) Develop elective training courses that instruct clinicians/nurses. (iv) Train independent local artisans use local materials to produce spare parts. (v) Install power-banking and apnoea-monitoring systems. (v) Institute ½yearly failure-preventive and auditing services.Based on Amadi et al (2010) study, outreach reduced average neonatal mortality by 25% (from 254/1000 to 192/1000); boosted morale/confidence of nurses/clinicians by 79%; accelerated discharge by 19%; boos

Conference paper

Amadi HO, 2013, Neonatal concerns in tropical subSaharan Africa, www.imeche.org/events/S1769, Appropriate healthcare technologies for developing countries: Low-cost, Frugal technology medical devices, Publisher: Institution of Mechanical Engineers

This medical outreach was designed to apply research techniques to determine the best practice that could improve the survival rate of newborn babies (neonates) within the tropical harsh climate of Western Africa. The highly populated vast expanse of the landscape of Nigeria, traversing the southern coastal rainforest to the dry northern desert lands, provided the suitable setting for this project.Lack of appropriate and effective science of neonatal thermoneutral control was initially identified as the major cause of poor physiological stabilisation of neonates especially the premature babies, leading to a high rate of mortality and morbidity. An affordable and most appropriate sustainable technology must be synthesised to reduce neonatal mortality. This has to be functional but culturally compliant for easy adaptability

Conference paper

Amadi HO, Mokuolu OA, Obasa T, 2013, Effect of high sun intensity on neonatal incubator functionality in a tropical climate, Journal of Neonatal Nursing, Vol: 19, Pages: 122-128, ISSN: 1355-1841

The effect of meteorologically-induced high room temperature on neonates and incubators in a tropical climate was studied. Two rooms were designated for the study. The main nursery hall served as the ‘control-room’ where environmental conditions remained unaltered. A sun-shading and wall-lagging method was applied to the ‘test-room’ to reduce the warming effect of high sunlight intensity. A weather monitoring station was installed to separately record meteorological changes outside the nursery and both study rooms. Incubator set-points and process temperatures were recorded hourly using digital thermometer from 8:00hr to 21:00 hr daily. All set ups were allowed to continue through the harmattan and dry season months. On the average, 80% of Incubators malfunctioned in the control-room, and 9% in the test-room. Minimisation of meteorological heat transmission into nursery wards is an essential factor to consider for designing and setting up a neonatal centre in a tropical climate.

Journal article

Lawan MI, Kawuwa MB, Oyedokun A, Mohammed H, Amadi HOet al., 2013, Effective nursery building that resolves tropical Evening Fever Syndrome (EFS) in neonates, Paediatrics Association of Nigeria Conference

Background: Recent publications1,2 have commented on neonatal morbidity due to climate-induced Evening Fever Syndrome (EFS) in neonates. EFS on neonates, especially those on incubator care, does not presently have any known clinical remedy as temperature of babies soars up to 42°C in some regions of Nigeria like Nguru during extreme-sunny days. FMC Nguru desperately resorts to ineffective sponging of babies (>37.9°C) with water. We hypothesise that any method of achieving naturally cooled nursery-rooms will eliminate EFS.Objective: To develop and validate a neonatal nursery building-technique that eliminates EFS. Methods: Ethical approval and carer-informed consent were obtained at FMC Nguru. Main nursery was the Control. Two laboratories constructed, a fresh building (Lab-1) and a renovated (Lab-2); surrounding walls doubled with 6cm of air space in-between. In Lab 1, floor was 120cm below ground-level; tap-water-operated heat-exchanger of 15mm copper piping was lined round the inside wall. Meteorological-data within and outside Laboratories/Control was collected via installed W 8681 weather-station. Neonates were nursed and vital-signs-data collected in all 3 apartments.Results: For extremely hot days (36°C-43°C outside-wind peak temp), control-room was cooler by 2.3°C, Lab-2(4.4°C), Lab-1(8.8°C). Average lowest relative-humidity: Control(17%), Lab-2(25%), Lab 1(46%). From captured data for hot days between February and October 2012, incubator over heat was frequent in Control-room but never occurred in Lab-1 or Lab-2; 71% of babies nursed in Control room required water-sponging 63 times, Lab-2(once), Lab-1(none).Conclusions: Correcting an existing SCBU building using the specifications of Lab-2 or constructing new ones with the specifications of Lab-1 will eliminate EFS and improve outcome.1 Amadi HO, 2012. Neonatal thermoneutrality, In: Tropical Medicine, Intech open, Croatia ISBN 978-953-51-0274-8; pp:513-5442 Amadi et al., 2012

Conference paper

Amadi HO, Azubuike JC, Osibogun AO, 2013, Expansion of the incubator capacity of Special Care Baby Units in Nigeria: a contribution to MDG4 target, Paediatrics Association of Nigeria Conference

Background: Millennium Development Goal 4 targets a two-thirds reduction in mortality in children under 5 years of age (U5MR) between 1990 and 2015. Since 40% of deaths in children under 5 years of age occurs in the first month of life (neonatal mortality), any measures undertaken to improve on newborn care would help contribute to the improvement in the under five mortality rate.As the deadline approaches, concerned players in the field are reviewing and questioning the effectiveness of the strategies being applied. In August 2012, the Lancet-Imperial Commission on Technologies for Global Health published a review1 which appeared to suggest that the time and funds spent on huge high-tech investments might not have been as cost-effective to global heath as was expected. The review did recognize the impact of Nigeria’s recycled incubator technology (RIT) as a positive contribution to the newborn health target of MDG4.In spite of the success of the RIT, it is necessary that Special Care Baby Units (SCBU’s) in Nigeria reexamine prevailing strategies, in order to ascertain that these provide progressive growth in incubator capacity and other facilities that ensure continuous and sustainable good quality of care.Objective: To examine the strategic expansion of incubator capacities in Special Care Baby Units of 5 tertiary health institutions in Nigeria over a ten-year period (2003 – 2012).Methods: The SCBUs of 16 tertiary heath institutions in Nigeria including the University of Benin Teaching Hospital (UBTH), Benin, Federal Medical Centre (FMC), Owerri, Federal Medical Centre (FMC), Nguru, Lagos University Teaching Hospital (LUTH), Lagos, University of Nigeria Teaching Hospital (UNTH), Enugu etc were recruited into the study at various times and closely monitored. Each Unit was assessed every six months and reports submitted with appropriate recommendations to the Hospital Management. Each Hospital was assisted with the institution of failure-preventi

Conference paper

Amadi HO, Bull AMJ, Emery RJH, 2012, Development and validation of a model for quantifying glenohumeral ligament strains during function, Proceedings of the Institution of Mechanical Engineers Part H: Journal of Engineering in Medicine, Vol: 226, Pages: 461-468, ISSN: 0954-4119

Analysis of the function of glenohumeral ligaments (GHLs) during physical joint manipulations is hindered by an inability to adequately image these tissues during the movements. This restricts functional biomechanics studies only to the manoeuvres that may be replicated cadaverically. There is, however, a clinical imperative to be able to investigate complex manoeuvres that exacerbate symptoms but cannot be easily conducted physically in the laboratory. The aim of this study was to develop and validate an algorithm for a computer simulation model that allows the quantification of glenohumeral ligament lengths during function. Datasets of the humerus and scapula pair were segmented to provide individual surface meshes of the bones and insertion points of each glenohumeral ligament on both bones. An algorithm was developed in which the glenohumeral ligament attachment-to-attachment length was divided into two straight lines, plus an arc overlaying the spherical wrapping portions. The model was validated by simulating two classical cadaveric studies from the literature and comparing results. Predictions from the model were qualitatively similar to the results of the two cadaveric studies by a factor of 91.7% and 81.8%, respectively. Algorithm application will allow investigation of functional loading of the glenohumeral ligaments during simulated complex motions. This could then be used to provide diagnostic understanding and thus, inform surgical reconstruction.

Journal article

Amadi HO, Fogg QA, Ugbolue UC, Emery RJH, Bull AMJet al., 2012, Reliability of a set of protractors for direct anatomical measurements around the glenoid and humeral head rims, Journal of Anatomy, Vol: 220, Pages: 525-528, ISSN: 0021-8782

Functional biomechanics studies of the glenohumeral (GH) soft tissues require an understanding of their sites of bony attachment. Anatomical positions of GH capsular structures have often been quantified relative to the rims of the glenoid and humeral head (HH). The aim of this study was twofold: (1) to quantify the reliability of a set of protractors that directly fit on to the glenoid and HH rims and (2) to use this to determine direct angular position referencing of landmarks and soft tissue attachment points. Three assessors independently used the protractors to assess nine prescribed landmarks on 30 dry bone specimens (15 glenoids and 15 HHs) recording the angular positions of the structures relative to the glenoid and HH. The collected data showed high levels of validity as indicated by the protractor’s intra‐ and inter‐assessor reliabilities: 98.2 and 98.7% for the glenoid component, and 96.2 and 96.5% for the humeral component, respectively. The device could be useful in anatomical studies, description of defects and pathologies on glenohumeral articulation, and planning of scapular reconstructive surgery.

Journal article

Amadi HO, 2012, Neonatal thermoneutrality in a tropical climate, Current topics in Tropical Medicine, Editors: Rodriguez-Morales, Croatia, Publisher: Intech, Pages: 513-544

Sub-Saharan African countries are notably among the nations with high neonatal mortality (NNMR) and morbidity rates. A number of issues have been previously raised in the literature in attempt to define some of the factors that contribute to these. However, little has been said of the impact of environmental temperature regulation on the wellness and survival of neonates in this region. The sub-Saharan Africa is well-known for its harsh climatic conditions of high sun intensity and ambient temperatures, often in excess of 35°C, coupled with societal condition of abject poverty. Nursing environment of the neonate, especially pre-terms, is a crucial factor for the maintenance of appropriate body temperature for the physiological stability of the newborn. Classical management of neonatal thermoneutrality in this region of Africa has been dominated by procedures that were imported from industrialised societies; these being fundamentally compliant to the peculiar climatic factors and social advantages of the countries of origin.In the last decade, there has been concerted effort to scientifically investigate factors that may be subtly contributing to high neonatal mortality and morbidity in this region. These include meteorological, social and technological factors that define the macro- and micro-environments immediate to the neonate. This knowledge is important for the tweaking or outright replacement of the present morbidity-high techniques. This chapter will attempt to isolate these factors and their consequences, and discuss the present interventions and techniques that are coincidentally yielding improved outcome in some neonatal centres in the region.Ineffective thermoregulation leads to other complications and patients’ poor response to treatment. Neonatal physiological stability enhanced by adequate thermoneutral control and humidification is an essential factor that enables the neonate to respond well to treatment thereby enabling effective management

Book chapter

Amadi HO, Bull AMJ, 2011, Algorithm and validation of a computer method forquantifying attachment locus of glenohumeral ligament invivo, Computer Methods in Biomechanics and Biomedical Engineering, Vol: 14, Pages: 1059-1063, ISSN: 1025-5842

The aim of this work was to validate an algorithm that quantifies the locus ofglenohumeral ligaments (GHL) attachments on glenohumeral joint (GHJ)bones.A computed tomography scan of a GHJ was segmented to reconstruct thehumerus, scapula, anatomical neck (AN) and glenoid rim (GR) into 3-Dmeshes of interconnecting nodal-vectors. These were applied to construct a‘clock face’ coordinate system in which three o’clock points anteriorly.Based on the assigned clock face coordinate frame and the fitted plane, theerror between the fitted plane and the actual bony node were quantifiedthrough manual data extraction. This was tested on 50 specimens.Mean algorithm quantification errors for GHL attachments were 4.8mm (SD2.2mm) and 4.5mm (1.7mm) for the humerus and glenoid, respectively.Further studies would apply this to investigate GHL length changes duringfunction and may suggest how these structures should be handled duringsurgical repairs.

Journal article

Amadi HO, Bull AMJ, 2010, A motion-decomposition approach to address gimbal lock in the 3-cylinder open chain mechanism description of a joint coordinate system at the glenohumeral joint, Journal of Biomechanics, Vol: 43, Pages: 3232-3236, ISSN: 0021-9290

In this study, the standard-sequence properties of a joint coordinate system were implemented for the glenohumeral joint by the use of a set of instantaneous geometrical planes. These are: a plane that is bound by the humeral long axis and an orthogonal axis that is the cross product of the scapular anterior axis and this long axis, and a plane that is bounded by the long axis of the humerus and the cross product of the scapular lateral axis and this long axis. The relevant axes are updated after every decomposition of a motion component of a humeral position. Flexion, abduction and rotation are then implemented upon three of these axes and are applied in a step-wise uncoupling of an acquired humeral motion to extract the joint coordinate system angles. This technique was numerically applied to physiological kinematics data from the literature to convert them to the joint coordinate system and to visually reconstruct the motion on a set of glenohumeral bones for validation.

Journal article

Amadi HO, 2010, Equipment: management and sustainability, Extant issues in the management of tertiary health institutions in Nigeria, Editors: Okpere, ISBN: 978-978-8408-65-9

Book chapter

Amadi HO, Bull AMJ, 2010, Protocol and Validation of a Computer Method for Determining Glenohimeral Ligament Attachments in vivo, 6th World Congress on Biomechanics

INTRODUCTION: Modelling the glenohumeral ligaments (GHL) kinematics in vivo has been hampered by poor imaging contrast of their bony attachments during function. The overcome of this problem may lead to a better understanding of their functions during different aspects of glenohumeral joint (GHJ) manoeuvres. A previous study has published a computational tool that reconstructs specified physiological kinematics of the glenohumeral joint (GHJ) bones1. Tracking the motion of the position vectors of GHL attachments on these bones would allow information on how the tissues are stretching, folding, and wrapping around the bones to be gained. The aim of this work was to develop and validate a protocol that allows the prediction of GHL attachments on a patient-specific glenoid and humerus.METHOD: Computed tomography scans of GHJ bones (humerus and scapula) were used in this study. All bones and their respective anatomical neck (AN) and glenoid rim (GR) outlines were individually reconstructed into 3-D surface meshes with interconnecting nodal vectors. Four reference nodal vectors were extracted. These corresponded to the positions of the humeral fovea capitis (f), humeral central superolateral point (p), scapular biceps insertion (b) and an arbitrary glenoid anterior point (a). The AN and GR were applied to quantify the normal vectors (vn) to their host plane-fits and the centres (c) of circle-fits. These were used in a ‘face-of-the-clock’ coordinate with early hours in the anatomical anterior direction. Dial unit vectors ucf and ucb (from centres c to reference points f and b respectively) were applied to a vector rotation algorithm2 to quantify the direction of a GHL attachment v when an angular position input φ° specified this in clock-face. The quantified direction was finally applied to the bone volume to identify the closest surface node as the locus of the attachment position.Algorithm Validation: 50 specimens (21 humeri and 29 scapulae) were ap

Conference paper

Amadi HO, 2010, Unique role of indigenous technology in sustainable healthcare delivery in Nigeria - An alumni inaugural lecture, Enugu Nigeria, 30 years of engineering training and practice in ESUT Nigeria, Publisher: Immaculate Publications Limited, Pages: 26-33

Conference paper

Amadi HO, Azubuike JC, Etawo US, Offiong UR, Ezeaka C, Olateju E, Adimora GN, Osibogun A, Ibeziako N, Iroha EO, Dutse AI, Chukwu CO, Okpere EE, Kawuwa MB, El-Nafaty AU, Kuranga SA, Mokuolu OAet al., 2010, The impact of recycled neonatal incubators in Nigeria: a 6-year follow-up study., Int J Pediatr, Vol: 2010

Nigeria has a record of high newborn mortality as an estimated 778 babies die daily, accounting for a ratio of 48 deaths per 1000 live births. The aim of this paper was to show how a deteriorating neonatal delivery system in Nigeria may have, in part, been improved by the application of a novel recycled incubator technique (RIT). Retrospective assessment of clinical, technical, and human factors in 15 Nigerian neonatal centres was carried out to investigate how the application of RIT impacted these factors. Pre-RIT and post-RIT neonatal mortalities were compared by studying case files. Effect on neonatal nursing was studied through questionnaires that were completed by 79 nurses from 9 centres across the country. Technical performance was assessed based on 10-indices scores from clinicians and nurses. The results showed an increase in neonatal survival, nursing enthusiasm, and practice confidence. Appropriately recycled incubators are good substitutes to the less affordable modern incubators in boosting neonatal practice outcome in low-income countries.

Journal article

Amadi HO, Bull AMJ, 2010, Surface-Contour Based Algorithm for Quantifying Glenohumeral Ligament Length Changes During Function, 23rd Annual Congress of International Society for Technology in advancement of Arthroplasty

Introduction: Advanced medical imaging techniques have allowed the understanding of the patterns of relative bone motions at human joints1. However, poor imaging contrasts of soft tissues have not allowed the full understanding of various glenohumeral ligaments (GHL) functions during glenohumeral joint (GHJ) manoeuvres. This is presently a significant limitation to research as these structures are said to be responsible for the passive stability of the GHJ2. Furthermore, the repairs of GHJ instability often take recourse to these structures3. Earlier studies have presented a model that numerically reconstructs or simulates GHJ motions4 and how the locus of bony attachment points of the GHLs on a dynamic GHJ could be numerically tagged and trailed5. The aim of this study was to advance these previous findings by developing an algorithm that allows the quantification of GHL lengths at any instantaneous position of the GHJ. Materials and Method: CT scan of a set of humerus and scapula was reconstructed into two individual surface meshes of interconnected nodes, each node having a unique vectorial identification in space. The two attachment nodes (a and b) of a GHL were identified on the bones5, (Figure 1). Least squares geometric sphere was fitted upon the humeral head (HH) and its centre (c) and radius (r) quantified6. Vectors a, b and c were applied to represent the ‘dominant ligament plane’ of Runciman (1993)7. This plane defined the path through which the ligament wrapped on the HH. The point of initial or end of contact of GHL on the HH was defined as the point on HH where a line from c intercepts the ligament at 90°. Total GHL length was calculated as the sum of its three segments, namely: (1) Proximal segment – a straight line from its glenoid attachment node to the point of initial contact (2) Wrap segment – an arc of (r) radius of curvature from initial to end contact points (3) Distal segment – a straight line from end contac

Conference paper

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