Cynthia Formosa

Thermographic Patterns of the Upper and Lower Limbs: Baseline Data

Objectives. To collect normative baseline data and identify any significant differences between hand and foot thermographic distribution patterns in a healthy adult population. Design. A single-centre, randomized, prospective study. Methods. Thermographic data was acquired using a FLIR camera for the data acquisition of both plantar and dorsal aspects of the feet, volar aspects of the hands, and anterior aspects of the lower limbs under controlled climate conditions. Results. There is general symmetry in skin temperature between the same regions in contralateral limbs, in terms of both magnitude and pattern. There was also minimal intersubject temperature variation with a consistent temperature pattern in toes and fingers. The thumb is the warmest digit with the temperature falling gradually between the 2nd and the 5th fingers. The big toe and the 5th toe are the warmest digits with the 2nd to the 4th toes being cooler. Conclusion. Measurement of skin temperature of the limbs using a thermal camera is feasible and reproducible. Temperature patterns in fingers and toes are consistent with similar temperatures in contralateral limbs in healthy subjects. This study provides the basis for further research to assess the clinical usefulness of thermography in the diagnosis of vascular insufficiency.

The importance of clinical biomechanical assessment of foot deformity and joint mobility in people living with type-2 diabetes within a primary care setting

AIMS The aim of the study was to assess foot morphology and document foot deformities and joint mobility in a cohort of subjects living with type-2 diabetes mellitus in Malta in a Primary Care setting. METHODS A retrospective observational study was conducted on 243 subjects who participated in a local pilot diabetes foot screening project. Assessments included hammer/claw toes, hallux valgus, hallux limitus, prominent metatarsal heads, bony prominences, Charcot deformity, plantar callus, foot type and ankle and hallux mobility. The clinical assessments used during this screening program were based on validated and previously published tools. RESULTS Upon clinical examination 38% of the sample was found to have developed some form of corns or callosities in their feet. Hallux valgus deformity was present in 49.4% of the sample, whilst 39% of the sample had hammer toes. Prominent metatarsal heads (24%), other bony prominences (44%) and limited joint mobility were also reported. Furthermore, 56% of the sample presented with unsuitable footwear and upon clinical biomechanical examination a further 28% of the sample required prescription orthosis. CONCLUSIONS/INTERPRETATION A significant proportion of participants living with type-2 diabetes presented with foot deformities which are known to be predictive of foot ulceration in this high risk population. This research conducted in a primary care setting highlights the importance of increased vigilance coupled with strengthening of existing screening structures and introducing clinical guidelines with regards to biomechanical assessment of the feet in a primary care setting in order to reduce the incidence of diabetes foot complications.

Diabetic foot complications in Malta: Prevalence of risk factors

AIMS The main objective of this research was to identify the prevalence of diabetes-related lower-extremity complications in a cohort of Maltese patients living with type 2 diabetes. METHODS A retrospective study was conducted on a cohort of 243 patients living with type 2 diabetes mellitus in two Maltese Health Centre catchment areas. A convenience sampling was adopted to recruit subjects from a local pilot diabetes foot screening program. The clinical assessments used during this screening program were based on validated and previously published tools such as: neuropathy disability score, vibration perception threshold, Semmes-Weinstein monofilaments, vascular status and foot deformities were evaluated. RESULTS The results from this study demonstrate that risk factors for foot deterioration and ulceration are common in Maltese population living with type 2 diabetes. Whilst, metabolic outcomes such as hypertension and dyslipidaemia were present in most subjects, peripheral vascular disease, peripheral sensory neuropathy and foot deformities were also common. Twenty-six per cent of the sample had to be referred for further vascular assessment following this screening program due to their critical vascular status. CONCLUSIONS/INTERPRETATION A significant proportion of Maltese participants living with type 2 diabetes presented with vascular insufficiency, abnormal neural function and deformities in the feet. Metabolic outcomes such as high blood pressure and high levels of cholesterol were also highly prevalent. Strengthening of existing screening structures is imperative in order to reduce the burden of this disease in Malta.

Negative Poisson's ratios in tendons: An unexpected mechanical response.

UNLABELLED Tendons are visco-elastic structures that connect bones to muscles and perform the basic function of force transfer to and from the skeleton. They are essential for positioning as well as energy storing when involved in more abrupt movements such as jumping. Unfortunately, they are also prone to damage, and when injuries occur, they may have dilapidating consequences. For instance, there is consensus that injuries of tendons such as Achilles tendinopathies, which are common in athletes, are difficult to treat. Here we show, through in vivo and ex vivo tests, that healthy tendons are highly anisotropic and behave in a very unconventional manner when stretched, and exhibit a negative Poissons ratio (auxeticity) in some planes when stretched up to 2% along their length, i.e. within their normal range of motion. Furthermore, since the Poissons ratio is highly dependent on the materials microstructure, which may be lost if tendons are damaged or diseased, this property may provide a suitable diagnostic tool to assess tendon health. STATEMENT OF SIGNIFICANCE We report that human tendons including the Achilles tendons exhibits the very unusual mechanical property of a negative Poissons ratio (auxetic) meaning that they get fatter rather than thinner when stretched. This report is backed by in vivo and ex vivo experiments we performed which clearly confirm auxeticity in this living material for strains which correspond to those experienced during most normal everyday activities. We also show that this property is not limited to the human Achilles tendon, as it was also found in tendons taken from sheep and pigs. This new information about tendons can form the scientific basis for a test for tendon health as well as enable the design of better tendon prosthesis which could replace damaged tendons.

Hidden dangers revealed by misdiagnosed peripheral arterial disease using ABPI measurement

AIM The aim of this study was to compare ankle brachial indices (APBI) with pedal waveforms utilizing the continuous wave Doppler in a population with diabetes mellitus. METHODS A prospective study design was employed to investigate the ABPI in a cohort of 49 people with type 2 diabetes mellitus. ABPI assessment was completed using a portable handheld Doppler and ankle pressures of <0.9 were taken as suggestive of peripheral arterial disease (PAD). Arterial spectral waveforms in each foot were also recorded and compared to the ABPI readings. RESULTS Inconsistencies were identified between ABPIs and waveform interpretations in the study population. Approximately 35% of subjects had inconsistencies between their ABPI result and waveform interpretation in their right or left foot. CONCLUSIONS Both ABPIs and Doppler waveforms should be used in the assessment of people with diabetes in order to screen for PAD. This would ensure an accurate assessment of PAD and would allow initiation of appropriate secondary risk factor control measures.

Prediction of wound healing after minor amputations of the diabetic foot

AIM To identify any significant differences in physiological test results between healing and non healing amputation sites. METHODS A single center prospective non-experimental study design was conducted on fifty subjects living with type 2 diabetes and requiring a forefoot or toe amputation. Subjects underwent non-invasive physiological testing preoperatively. These included assessment of pedal pulses, preoperative arterial spectral waveforms at the ankle, absolute toe pressures, toe-brachial pressure index and ankle-brachial pressure index. After 6 weeks, patients were examined to assess whether the amputation site was completely healed, was healing, had developed complications, or did not heal. RESULTS There was no significant difference in ABPI between the healed/healing and the non-healing groups. Mean TBI (p=0.031) and toe pressure readings (p=0.014) were significantly higher in the healed/healing group compared to the non healing group. A significant difference was also found in ankle spectral waveforms between the two groups (p=0.028). CONCLUSIONS TBIs, toe pressures and spectral waveforms at the ankle are better predictors of likelihood of healing and non-healing after minor amputation than ABPIs. ABPI alone is a poor indicator of the likelihood of healing of minor amputations and should not be relied on to determine need for revascularization procedures before minor amputation.

Shock attenuation properties at heel strike: Implications for the clinical management of the cavus foot.

BACKGROUND This study explored the relationship between foot types and corresponding variations in shock attenuating properties of the heel. METHODS Thirty matched participants were assigned to 3 groups: pronated, neutral, and supinated. A low-mass accelerometer was mounted to the calcaneus of the right leg of each participant. RESULTS Acceleration at heel strike for supinators was significantly higher than that in individuals with pronated and neutrally aligned feet. No significant difference was found in mean and maximum acceleration at heel strike between pronators and neutrals. CONCLUSION Cavus feet undergo significantly higher mean and maximum acceleration forces than neutrally aligned and pronated feet.

Childhood Adiposity – Solutions for a National Epidemic

The problem of childhood adiposity has reached epidemic proportions in many parts of the world and has become a public health challenge. Obesity co-morbidities are expected to increase progressively in line with the recent observed increase in childhood adiposity. Unless a solution is found, adiposity trends will escalate increasing mortality . To date the understanding of why this is happening is rudimentary and it seems that no coherent and effective methods have been developed to overcome this condition. Biological influences, parental influences and societal influences need all to be addressed if childhood adiposity is to be managed appropriately. Effective policies and programmes are needed at both global and national levels in order to address childhood adiposity. In light of these findings this paper explores the literature to provide a comprehensive understanding of the cause and effect in childhood adiposity. This paper also provides recommendations and possible solutions/methods of intervention for what could be considered a National epidemic.

Establishing Differences in Thermographic Patterns between the Various Complications in Diabetic Foot Disease

Aim To evaluate the potential of thermography as an assessment tool for the detection of foot complications by understanding the variations in temperature that occur in type 2 diabetes mellitus (DM). Methods Participants were categorized according to a medical examination, ankle brachial index, doppler waveform analysis, and 10-gram monofilament testing into five groups: healthy adult, DM with no complications, DM with peripheral neuropathy, DM with neuroischaemia, and DM with peripheral arterial disease (PAD) groups. Thermographic imaging of the toes and forefeet was performed. Results 43 neuroischaemic feet, 41 neuropathic feet, 58 PAD feet, 21 DM feet without complications, and 126 healthy feet were analyzed. The temperatures of the feet and toes were significantly higher in the complications group when compared to the healthy adult and DM healthy groups. The higher the temperatures of the foot in DM, the higher the probability that it is affected by neuropathy, neuroischaemia, or PAD. Conclusions Significant differences in mean temperatures exist between participants who were healthy and those with DM with no known complications when compared to participants with neuroischaemia, neuropathy, or PAD. As foot temperature rises, so does the probability of the presence of complications of neuropathy, neuroischaemia, or peripheral arterial disease.

Automated Segmentation and Temperature Extraction from Thermal Images of Human Hands, Shins and Feet

The use of thermography has been considered for a wide range of medical applications, which often require the extraction of temperature values from specific points of interest on the human body. However, temperature extraction is typically carried out manually, rendering the process both lengthy as well as highly subjective. In this work we propose a number of methods to automatically segment and extract temperature readings from thermal images of human hands, shins and feet that can be employed in several clinical applications. Tests conducted using thermal images from the body regions of interest have shown that the implemented feature detection and region growing methods can provide accurate results with a correct detection rates of 100% in the case of the shin regions and detection rates above 90% for hand and foot regions.