Short papers
O01 Characteristics and treatment of patients with intermittent claudication. A comparison between UK and Maltese populations
Anabelle Mizzi
Faculty of Health Sciences, University of Malta, Msida, Malta
Background: Intermittent claudication (IC) is the most common symptom of peripheral arterial disease (PAD). It is strongly associated with an increased risk of myocardial infarction, stroke and cardiovascular mortality by up to 4 times greater than in patients without IC. Over the years effort has been made within the health sector to raise awareness of the cardiovascular risk factors present inpatients with PAD. However, a prospective registry of patients was still lacking.
Therefore, a prospective registry of PAD risk factors, events and peripheral perfusion of patients with IC referred from primary care to specialist vascular clinics was undertaken. Baseline characteristics and treatments were compared to previously published UK data (PREPARED-UK). This information may provide a point of reference by which future health practices may potentially improve.
Methods: A cross-sectional observational study was conducted, where all patients referred to a Vascular Clinic in a local hospital over 12 months, due to IC were invited to participate. Individuals who gave informed consent to participate were assessed for PAD by hemodynamic analysis. A full medical history including previous cardiac events or stroke, medications taken and associated participant demographics were noted. Results were compared to PREPARED-UK data.
Results: A total of 150 consecutive participants were recruited. These included all the patients referred to the specialist vascular clinic from primary care GP clinics. The main demographic characteristics of enrolled participants indicate that the two populations are similar in age, BMI, smoking status and anti-platelet therapy. However, a much higher prevalence of hyperlipidaemia (HLD), diabetes, hypertension (HTN) and statin use is observed in the Maltese prospective registry compared to data published by in the PREPARED-UK registry (HLD 78.4% vs 43.1%, Diabetes 66.2% vs 20.1%, HTN 84% vs 55.4%, statins 76% vs 40% respectively).
Conclusion: Our findings indicate a distinct difference in prevalence of important cardiovascular risk factors between the two populations. Hypertension, hyperlipidaemia and diabetes have been linked with a 7-fold increased risk of having a cardiovascular vascular event. However, similar to the UK population, about one third of the patients were not prescribed anti-platelet medication or statins. Despite the Consensus Report stating that antiplatelet therapy should be used routinely in PAD, with aspirin as the first line treatmF25ent, patients are still poorly managed prior to referral to the vascular specialist indicating an underestimation of the serious nature of the disease. Therefore, more referrals by primary health GPs to podiatrists for vascular assessment are required, so that once PAD is diagnosed immediate referral for risk factor management is undertaken. Additionally, follow-up of these patients would help to ensure that important risk factors are being managed while also monitoring PAD status.
O02 Does PRP have antimicrobial properties?
Jill Cundell
School of Health Sciences, Ulster University, Belfast Health and Social Care Trust, Belfast, Northern Ireland
Background: Platelet Rich Plasma (PRP) is a blood product having a platelet concentration above baseline. In vitro studies have reported that PRP may significantly inhibit the growth of undesirable pathogens in diabetic foot ulcers (Bielecki et al. 2007, Moojern et al. 2008). This study aimed to determine the inherent antibacterial properties of autologous PRP from 40 study participants. The participants consisted of 3 groups. Healthy diabetics - no complications of diabetes and a HbA1c <8% (n=13) and their healthy age gender matches (n=13) and a discreet group of 14 participants who had a non-healing diabetic foot ulcer with no antibiotic therapy in the preceding 21 days. Ethical approval was obtained from ORECNI (10/NIRO2/30).
Method: A sample of 55ml of whole venous blood was drawn from each participant and prepared as per the manufacturer’s instructions to produce PRP.The antibacterial efficacy of PRP was established using the well diffusion assay. Five wells were aseptically created in each nutrient agar plate seeded with lawns of S. aureus (NCTC 8329), Ps. aeruginosa (NCTC 10780), Methicillin-resistant S. aureus (MRSA) (NCTC 8323), MRSA - clinical isolate, S. pyogenes (β Haemolytic Streptococcus) (NCTC10876), Proteus vulgaris (NCTC10031) and E. coli (NCTC09001). These bacteria are of significance in diabetic foot wounds (Lipsky and Berendt 2000, Vardakas et al., 2008). PRP from the study participants was aseptically transferred into 4 of the wells; the 5th (control) well contained Ringer's solution. The plates were incubated at 37 °C for 24 hours, and the resultant zones of inhibition were used to provide a semi-quantitative estimation of antibacterial activity.
Results: Zones of inhibition (ZOI) were observed on the lawns of S.aureus, S. pyogenes, and Proteus vulgaris, of all participants. ZOI were also observed on the lawns of MRSA (both types) in the age gender-matched group and participants with an active diabetic foot wound. Enhanced growth of Ps. aeruginosa was observed in the healthy participants (n=11), as previously found by Bielecki et al. (2007), but was also observed in participants with diabetes and participants with diabetes (n=10) and an active diabetic foot wound (n=13).
Conclusion: These findings may be clinically significant, as they demonstrate that PRP has a wider than previously recognised range of antimicrobial activity against infecting/contaminating bacteria. Zones of inhibition were not identified for all the participants on the plates with lawns of these organisms. The significance of these effects requires further investigation in the clinical environment as the in vitro findings may not mimic what happens in vivo.
Clinically, the lack of antimicrobial properties against Ps. aeruginosa is important as Ps.aeruginosa causes 9.3% to 31% of diabetic foot infections (Viswanathan, 2007); is known to form biofilms, which delay wound healing (Swarna et al., 2012) and has been linked to the migration of keratinocytes. These observations are significant in wound healing (Loryman and Mansbridge 2007). The findings of this work indicate that it would be advisable to sample a wound prior to the application of autologous PRP to ensure there was no evidence of the presence of Ps. aeruginosa.
References
1. Bielecki, T., Gazdzik, T., Arendt, J., Szczepanski, T., Król, W. and Wielkoszynski, T. 2007. Antibacterial effect of autologous platelet gel enriched with growth factors and other active substances: an in-vitro study. Journal of Bone and Joint Surgery (British volume), 89 (3), 417-420.
2. Lipsky, B., Berendt, A. 2000. Principles and practice of antibiotic therapy of diabetic foot infections. Diabetes/Metabolism Research and Reviews, 16 (Suppl), 42-46.
3. Loryman, C., Mansbridge, J. 2007 Inhibition of keratinocyte migration by lipopolysaccharide Wound Repair and Regeneration 16(1) 45 -51.
4. Moojen, D., Everts, P., Schure, R., Overdevest, E., van Zundert, A., Castelein, J., Creemers, R., Dhert, L., Wouter, J. 2008. Antimicrobial activity of platelet-leukocyte gel against Staphylococcus aureus. Journal of Orthopaedic Research, 26 (3), 404-410.
5. Swarna, S., Madhavan, R., Gomathi, S., Thamaraiselvi, D., Thamaraiselvi, S. 2012. A study of Biofilm on Diabetic Foot Ulcer. International Journal of Research in Pharmaceutical and Biomedical Sciences, 3 (4), 1809-1814.
6. Vardakas, K., Horianopoulou, M., Falagas, M. 2008. Factors associated with treatment failure in patients with diabetic foot infections: An analysis of data from randomized controlled trials. Diabetes Research and Clinical Practice, 80 (3), 344-351.
7. Viswanathan V. 2007 The diabetic foot: perspectives from Chennai, South India. International Journal of Lower Extremity Wounds. 6(1):34-6.
O03 Virtually optimised foot orthoses for offloading the diabetic foot: A randomized crossover study
James Woodburn
School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, Scotland, UK
Background: Integration of objective biomechanical measures of foot function into the design process for foot orthoses has been shown to provide enhanced plantar tissue protection for individuals at-risk of plantar ulceration [1]. The use of virtual simulations utilizing numerical modeling techniques offers a potential approach to further optimize these devices [2]. In a patient population at-risk of foot ulceration, we aimed to compare the pressure offloading performance of foot orthoses that were optimized via numerical simulation techniques against shape-based devices.
Methods: Twenty participants with diabetes and at-risk feet were enrolled in this study. Three pairs of personalised foot orthoses: one based on shape data and subsequently manufactured via direct milling; and two were based on a design derived from shape, pressure, and ultrasound data which underwent a finite element analysis-based virtual optimization procedure (Abaqus, V6.10; Simulia, Providence, RI). A simplified model of forefoot anatomy incorporating floor and shoe components was built for each participant (Figure 1) [3]. A computer-aided designed orthosis was added to the model and underwent a standardized modification procedure by increasing the height of a metatarsal bar and removing material under each metatarsal head until the regional peak plantar pressures were predicted to be <200 kPa or the limits of the possible modifications had been reached. For the optimised orthoses, one pair was manufactured via direct milling, and a second pair was manufactured through 3D printing (Figure 2). The offloading performance of the foot orthoses was analyzed for forefoot regions identified as having elevated plantar pressures using an in-shoe plantar pressure measurement system (Pedar-X, Novel GmbH, Munich, Germany).
Results: Seventy-six regions-of-interest were identified from the barefoot plantar pressure data. In 88% of these regions, the milled, optimized orthosis design shape showed lower peak pressures than the standard design, with a mean difference of 41.3 kPa. For the printed optimized foot orthoses, lower peak pressures were seen in 74% of the regions-of-interest compared to the standard devices, with a mean difference of 40.5 kPa. Repeated measures ANOVA across orthosis conditions revealed significant differences between groups (p < 0.001), with pairwise comparisons showing that both sets of virtually optimized devices provided significantly greater forefoot offloading at regions of interest than the standard orthoses (milled: p < 0.001, 95% CI [31.1, 51.5]; printed: p < 0.001, 95% CI [26.4, 54.5]). There were no significant differences in offloading performance between the milled and printed optimized insoles.
Conclusion: The integration of virtual optimization into the foot orthosis design process resulted in improved offloading performance compared to standard, shape-based devices.
References
[1] Ulbrecht, J.S., Hurley, T., Mauger, D.T., Cavanagh, P.R., (2014). Prevention of recurrent foot ulcers with plantar pressure-based in-shoe orthoses: the careFUL prevention multicenter randomized controlled trial. Diabetes Care 37, 1982-1989.
[2] Telfer, S., Erdemir, A., Woodburn, J., Cavanagh, P.R., (2014). What has finite element analysis taught us about diabetic foot disease and its management? a systematic review. PLoS One 9, e109994.
[3] Telfer, S., Erdemir, A., Woodburn, J., Cavanagh, P.R., (2016). Simplified versus geometrically accurate models of forefoot anatomy to predict plantar pressures: a finite element study. J. Biomech. 49, 289-294.
O04 A thermographic investigation of the diabetic foot with peripheral arterial disease using the angiosome concept
Alfred Gatt
Faculty of Health Sciences, University of Malta, Msida, Malta
Objective: To compare temperature changes following a challenge of limb elevation, in 3 forefoot angiosomes between participants living type 2 diabetes mellitus (T2DM) and with mild and severe peripheral arterial disease (PAD), compared to participants with T2DM only.
Method: T2DM participans were categorized in mild PAD, severe PAD and healthy groups. All underwent thermal imaging using a Flir T630 camera in a room with temperature controlled at 23oC, whilst lying in a supine position. Successive thermal images were then taken at 1 minute intervals after the lower limbs were elevated for 5 minutes. Thereafter, the lower limbs were lowered and imaged again after 1 minute. Data were extracted utilizing the angiosomeconcept, with mean temperatures of the hallux, medial and lateral forefoot being analyzed.
Results: 42 limbs from 27 participants were analysed. Mean resting temperatures of all angiosomes of participants with mild and severe PAD were higher than those with no PAD. A significant difference in the mean initial temperature between the groups was found in the medial and lateral forefoot angiosomes (p=0.048, p=0.049 respectively), whilst at the hallux these temperatures were not significant (p=0.165). Mean temperature change between the consecutive images for each challenge, between the 3 groups, resulted in no significant changes. Mean initial temperatures had statistically significant difference between all angiosomes in all groups.
Discussion: Baseline thermographic characteristics of healthy adult feet have been previously established in the literature (1). Consequently, thermal characteristics of people living with PAD can be compared. It has also been highlighted that vascular perfusion is affected by elevation of the limb. Thus the authors hypothesised that such a change in perfusion would result in a change in temperature that could be detected by thermography. This could be compared to the thermal characteristics of patients living with type 2 DM and a normal vascular supply, thus enabling the creation of a possible thermal algorithm that could discriminate between healthy and PAD feet. When comparing initial mean temperatures, a significant difference was detected in the medial and lateral angiosomes, although mean temperatures were clearly higher in all 3 angiosomes of the PAD groups. This confirms previous, possibly controversial results of two studies by Gatt et al (2,3), which reported that PAD patients exhibit higher mean temperatures than their healthy controls.
Conclusions: Results from this study confirm that individuals with both mild and severe PAD have significantly higher forefoot temperatures when investigated through the angiosome concept. The use of a challenge through elevation of the foot for 5 minutes did not affect the thermal pattern significantly.
References
1. Gatt A, Formosa C, Cassar K, Camilleri KP, De Raffaele C, Mizzi A, et al. (2015) Thermographic patterns of the upper and lower limbs: baseline data. Int J Vasc Med. Article id 831369; DOI http://dx.doi.org/10.1155/2015/831369.
2. Gatt A, Kevin Cassar, Owen Falzon, Kenneth P. Camilleri, Stephen Mizzi, Anabelle Mizzi, Cassandra Sturgeon, Jean Gauci, Nachiappan Chockalingam, Cynthia Formosa. (2018). The identification of higher forefoot temperatures associated with peripheral arterial disease in type 2 diabetes mellitus as detected by thermography. Primary Care Diabetes. 12(4):312-318.
3. Gatt A, Falzon O, Cassar K, Ellul C, Camilleri K P, Gauci J, Stephen Mizzi PhD, Mizzi A, Sturgeon C, Camilleri L, Chockalingam N and Cynthia Formosa. 2018 Establishing differences in thermographic patterns between the various complications in diabetic foot disease. Intl J Endocrinol .Article ID: 9808295 https://doi.org/10.1155/2018/9808295
O05 Neurological assessment using a portable nerve conduction device in a clinical setting
Simbarashe Tanyanyiwa
Faculty of Health Sciences, University of Southampton and Solent NHS Trust, Southampton, UK
Objective: There is a need to accurately identify neuropathy in people with type 2 diabetes, to help with risk stratification, and thus guide appropriate clinical management. Current guidelines by the National Institute for Health and Care Excellence (NICE) on the diabetic foot assessment are constructed around determining the risk of ulceration (NICE NG19 2015). The sensory neurological assessments however presents challenges as they are poorly standardised, rely on subjective responses, remain vulnerable to operator variability and are poorly sensitive at identifying early neuropathy. Therefore the recommended sensory assessments are not sensitive enough at detecting early neurological impairment, which further affects the effectiveness of early intervention strategies.
Aim: This study aimed to compare the extent of agreement in detecting neuropathy in participants with type 2 diabetes, between the recommended NICE 10g monofilament, against a portable nerve conduction device (NCstat ® DPNCheck; Neurometrix, Inc., Waltham, MA, USA).
Problem statement: The current NICE recommended sensory assessment methods are poorly able to identify early diabetic neuropathic impairment.
Methods: Recruitment: 28 adult participants between 18 - 65 years of age, with type 2 diabetes were recruited at Solent NHS Trust sites.
Ethical approval
The study was processed through the University of Southampton's Ethics and Research Governance Online (ERGO 13474), and ethical approval was obtained through the Integrated Research Application System (IRAS 170265), and Research Ethics Committee (17/LO/2033) and the local Health Research Authority.
Assessment of never function: The DPN-Check measures nerve conduction velocity of the sural nerve (meters per second) and amplitude (microvolts) following the procedure below, with normative values and a chart for interpretation. The whole nerve conduction procedure took on average 15 seconds to complete. The monofilament will be used to assess sensory neuropathy with scores out of 10.
Results: Cohen's κappa was run to determine the extent of agreement between the two instruments on whether 28 individuals with type 2 diabetes had neuropathy. There was poor agreement between the two instruments, κ = .329 (95% CI, 0.14 to 0.52), p = 0 .001. The 10g monofilament classified 19 participants as having no sensory deficit, and therefore at low risk of developing ulceration. The DPN-check classified 13 participants as having no sensory deficit. The 10g monofilament was unable to detect neuropathy in 24% of participants who showed nerve conduction abnormalities, and there was further disagreement in staging of the neuropathy between the two instruments.
Conclusion: The 10g monofilament demonstrated an impaired ability to detect neuropathy, and poorly agreed with an objective reference standard. This leaves the 10g monofilament underestimating ulceration risk; and poorly risk stratifies individuals with type 2 diabetes. Participants at higher risk status would be mis-classified and treated as lower risk, with limited access to more intensive management provided to higher risk individuals. The current health service guidelines suggest a wait for a change in the risk status to justify more intensive intervention. By this time it may be too late to implement effective strategies. The nerve conduction device (DPN-Check) has the potential to accurately determine an individual’s’ ulceration risk status in the early stages of diabetes, and guide timely management
References
1. Arad, Y., et al., Beyond the monofilament for the insensate diabetic foot: a systematic review of randomized trials to prevent the occurrence of plantar foot ulcers in patients with diabetes. Diabetes Care, 2011. 34(4): p. 1041-6.
2. Chatzikosma, G., et al., Evaluation of sural nerve automated nerve conduction study in the diagnosis of peripheral neuropathy in patients with type 2 diabetes mellitus. Arch Med Sci, 2016. 12(2): p. 390-3.
3. Crawford, F., et al., A systematic review and individual patient data meta-analysis of prognostic factors for foot ulceration in people with diabetes: the international research collaboration for the prediction of diabetic foot ulcerations (PODUS). Health Technol Assess, 2015. 19(57): p. 1-210.
4. de Souza, R.J., A. de Souza, and M.D. Nagvekar, Nerve conduction studies in diabetics presymptomatic and symptomatic for diabetic polyneuropathy. J Diabetes Complications, 2015. 29(6): p. 811-7.
5. Dyck, P.J., et al., Assessing decreased sensation and increased sensory phenomena in diabetic polyneuropathies. Diabetes, 2013. 62(11): p. 3677-86.
6. Feng, Y., F.J. Schlosser, and B.E. Sumpio, The Semmes Weinstein monofilament examination is a significant predictor of the risk of foot ulceration and amputation in patients with diabetes mellitus. J Vasc Surg, 2011. 53(1): p. 220-226 e1-5.
7. Kong, X., et al., Utilization of nerve conduction studies for the diagnosis of polyneuropathy in patients with diabetes: a retrospective analysis of a large patient series. J Diabetes Sci Technol, 2008. 2(2): p. 268-74.
8. Muniz, E.C., et al., Neuropathic and ischemic changes of the foot in Brazilian patients with diabetes. Ostomy Wound Manage, 2003. 49(8): p. 60-70, 72-3.
9. Rayman, G., et al., The Ipswich Touch Test: a simple and novel method to identify inpatients with diabetes at risk of foot ulceration. Diabetes Care, 2011. 34(7): p. 1517-8.
10. Samuel, B.S. and S.J. Appel, Identifying early signs of peripheral neuropathy among patients with diabetes mellitus. Nurse Pract, 2016. 41(1).
11. Sharma, S., et al., The Ipswich Touch Test: a simple and novel method to screen patients with diabetes at home for increased risk of foot ulceration. Diabet Med, 2014. 31(9): p. 1100-3.
O06 Morbidity of the contralateral limb following major lower limb amputation in patients with peripheral arterial disease and/or diabetes: Audit of two regional vascular centres
Heidi Siddle
School of Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds, UK
Background: Major amputation of the lower limb, below or above knee, is a devastating consequence of dysvascularity arising from peripheral arterial disease (PAD) and diabetes. Contralateral major lower limb amputation (LLA) is reported to be more common after an ipsilateral (index) major LLA than after an ipsilateral minor amputation1. Quality of life impacts include pain, loss of independence and emotional difficulties2.
A recent National Confidential Enquiry into Patient Outcome and Death (NCEPOD) report into peri-operative care of patients undergoing major LLA, deemed there to be room for improvement in clinical care in 24.5% of reviewed cases, organisational care in 9.6% and both in a further 17.9%3. The NCEPOD report specifically highlighted the limited access to services including specialist podiatry for care of the contralateral limb in the peri- and post-operative periods (37.8% and 29% respectively) for those patients undergoing a major LLA3. The Vascular Society of Great Britain and Ireland published a Best Practice Clinical Care Pathway in April 2016, yet specific treatment guidance is unavailable for clinicians to optimise care to protect the contralateral limb4.
Objective: This audit aimed to address a significant gap in the existing evidence, providing data regarding the important clinical outcomes, in particular time to complications of the contralateral limb in the 12 month period following an initial major LLA in people with PAD and/or diabetes.
Methods: Audit data was collected from a consecutive sample of eligible patients for 12 months following a major LLA in two regional vascular centres in the UK.
The incidence of new contralateral foot ulceration, minor/major amputation of the contralateral limb and date of death were recorded in the 12 months following major LLA.
Results: 383 patients had a major LLA, 249 (65.0%) patients were male and the mean age of patients at the time of undergoing a major LLA was 68.8 years. 210 (54.8%) patients were diagnosed with diabetes at the time of their major LLA. 102 (26.6%) patients died within 12 months following their major LLA, 30 (17.2%) were known to have died within the first 30 days, 46 (26.4%) within three months, and 73 (42.0%) within six months following their major LLA.
18 (4.7%) patients had a complication (foot ulceration, minor amputation or major LLA) with the contralateral limb within the first 30 days following their index major LLA, 68 (17.8%) within three months, 99 (25.8%) within six months and 129 (33.7%) within 12 months. 89 (70.0%) patients with a complication were diabetic.
Conclusions: This is the first audit to report time to complications of the contralateral limb in the 12 months following a major LLA in patients with diabetes and/or PAD. Complications of the contralateral limb are consistently higher in patients who have diabetes. Evidence provided through this audit highlights the need for an improved understanding of the process that leads to contralateral limb morbidity following major LLA. This audit further indicates the need to optimise care to protect the contralateral limb following a major LLA and provide guidance for carers, patients and clinicians.
References
1. Izumi, Y., Satterfield, K., Lee, S., and Harkless, L.B. (2006) Risk of reamputation in diabetic patients stratified by limb and level of amputation: a 10-year observation. Diabetes Care. 29(3): p. 566-70.
2. Hernandez-Osma, E., Cairols, M.A., Marti, X., Barjau, E., and Riera, S. (2002) Impact of treatment on the quality of life in patients with critical limb ischaemia. European Journal of Vascular and Endovascular Surgery. 23(6): p. 491-494.
3. National Confidential Enquiry into Patient Outcome and Death (NCEPOD), Lower Limb Amputation: Working Together (2014).
4. The Vascular Society of Great Britain and Ireland. A Best Practice Clinical Care Pathway for Major Amputation Surgery. April 2016.
O07 An investigation of mortality and foot morbidity following minor foot amputations in patients with diabetes
Cynthia Formosa
Faculty of Health Sciences, University of Malta, Msida, Malta
Aim: The aim of this study was to determine the one-year rate of healing, re-ulceration, re-amputation and mortality following minor foot amputations in patients living with diabetes.
Methods: A single-centre non-experimental research design was employed. Eighty-one participants living with type 2 diabetes and presenting for an elective toe amputation due to bone exposure or gangrene were recruited. Prior to the amputation, participants were assessed for demographics, vascular supply and neuropathy to classify the foot type according to international guidelines. Subjects were then followed every 3 months post-amputation for a period of 1 year. During each visit, subjects were assessed for progress of amputation site. Healing was noted, however when amputation sites failed to heal, participants were grouped according to the presence of new ulcerations, need for further amputation, presence of infection or mortality. At the end of the 12-month period, data was analysed to determine the rate of healing, re-ulceration, re-amputation and mortality following minor foot amputation.
Outcomes: 80.2% of study cohort had a healed amputation site after 12 months. Mortality was recorded amongst 7.4% of the cohort. The remaining 12.4% of participants had an amputation site which was still open and with half of them being infected. During the 12 months of study, 59.3% of patients had to undergo another surgery to revise amputation site or had to amputate a new site whilst 45.7% of the patients presented with an ulcer. Only 20.9% of participants had no complications following the amputation implying that most participants had to go through multiple surgeries and events such as ulcerations and infections prior to complete wound closure.
Discussion: Despite the high rate of healing noted amongst the cohort after one year taking measures to prevent infections, re-ulceration and re-amputation and ultimately death is very important for patients with diabetic minor foot amputations. Efforts should be made to minimize these risks since it has been documented that such complications following surgery decreases patients’ quality of life and increases mortality rates [Dillingham &Pezzin, 2008]. More studies are warranted to evaluate these outcomes further.
Relevance/Impact: This study focused on all the possible outcomes following minor foot amputations amongst a population with a high prevalence rate of diabetes. Similar studies only focus on one of the eventualities, mainly mortality or re-amputation but this study is unique since it evaluated all possible outcomes following amputation over a one-year period. A better and deeper understanding of the factors that contribute to healing, re-ulceration, re-amputation and death following elective foot amputations is important if improvements in diabetes outcomes are to be achieved [Maher & Bond, 2017].
References
1. Dillingham, T. and Pezzin, L. (2008) Rehabilitation setting and associated mortality and medical stability among persons with amputations. Arch Phys Med Rehabil. 89: 1038-45.
2. Maher, A. and Bond, H. (2017) Podiatric surgery and the diabetic foot: n audit of a community-based diabetic foot surgery. The Diabetic Foot Journal. 20(2), 89-94.
O08 Motivational interviewing as an intervention to improve adherence behaviours for the prevention of diabetic foot ulceration - a systematic review
Jodi Binning
School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK
Aim: Preventative strategies for diabetic foot ulceration are effective when patients adhere to advice. Therefore interventions aimed at improving adherence are required. A systematic review was conducted to determine the effectiveness of motivational interviewing as an intervention to improve adherence behaviours for the prevention of diabetic foot ulceration.
Method: Electronic searches were run without date or language restrictions across 13 Medical, Health, Psychology and Research databases. Studies were selected if they fulfilled the inclusion criteria: Population: Age 18+ with type I or II diabetes at risk of ulceration. Interventions: Motivational interviewing as the main intervention or as a component. Comparators: All types of control groups were accepted.
Outcomes: A new episode of ulceration and/or at least one behavioural outcome measure. RCTs and quasi-experimental prospective studies were accepted. Two review authors independently assessed eligibility using Covidence © software. Complete agreement was achieved on 45 of 47 studies. Agreement by discussion was easily reached for the 2 remaining studies. Data on foot risk, duration of diabetes and demographic profile was extracted. Study design, number of participants, intervention description, intervention setting, mode of delivery, outcome measures and time points were recorded. An analysis on intervention content was conducted using the Behavioural Change Taxonomy (Michie et al. 2013).
Results/Discussion: Five studies met the inclusion criteria and all were assessed as having a high risk of bias. Studies differed in aims, mode and duration of intervention delivery, and measures and outcomes. This prevented the pooling of data to determine overall effectiveness of motivational strategies on adherence. Four of five studies used motivational / behavioural techniques as a part of a suite of interventions. These four studies used techniques based on goals and planning, social support and identifying consequences of the targeted behaviour. Two of these studies claimed the intervention was effective; however bias and population characteristics indicate that these results are not generalizable. One study used motivational interviewing as the main intervention and found improved short term adherence (from 49% to 84%). This effect returned to baseline after 3 months. This study was exploratory with ten participants. No studies adequately adopted strategies for the least motivated subjects whose barriers to adherence were belief based. Evidence from wider literature suggests motivational interviewing and behavioural change techniques are more effective at improving adherence compared to standard patient education (Rubak et al. 2005, Ogden 2016)
Conclusion: There is insufficient evidence to determine whether motivational interviewing is effective at improving adherence behaviours for the prevention of diabetic foot ulceration. More research is needed to explore relationships between motivation, behaviours, adherence and outcomes for this population.
References
Michie, S., et al., 2013. The behavior change technique taxonomy (v1) of 93 hierarchically clustered techniques: building an international consensus for the reporting of behavior change interventions. Annals of Behavioral Medicine: A Publication of the Society of Behavioral Medicine. 46(1), pp. 81-95.
Ogden, J., 2016. Celebrating variability and a call to limit systematisation: the example of the Behaviour Change Technique Taxonomy and the Behaviour Change Wheel. Health Psychology Review. 10(3), pp. 245-250.
Rubak, S., Sandbaek, A., Lauritzen, T. and Christensen, B., 2005. Motivational interviewing: a systematic review and meta-analysis. The British Journal of General Practice : The Journal of the Royal College of General Practitioners. 55(513), pp. 305.
O09 Does foot posture matter? A biomechanical perspective
Andrew Buldt
Discipline of Podiatry School of Allied Health, La Trobe University, Melbourne, Australia
Background: There is evidence that non-normal foot postures, such as pes planus or pes cavus, are associated with increased odds of injury to the lower extremity. Hence, foot posture continues to be a commonly measured clinical variable. However, recent research has cast doubt on the clinical use of some methods of assessing foot posture to predict foot function. In addition, biomechanical research has been inconclusive in identifying the link between foot posture and foot function, mostly due to the use of tools with that are not valid or reliable to classify foot posture and inconsistency in approaches to report biomechanical findings. This presentation will report the findings of three separate studies that aimed to compare walking gait biomechanics between healthy individuals with either planus, cavus or normal foot postures, classified using reliable foot posture measurement tools.
Methods: One hundred participants, aged 18-47, were classified as either normal, pes planus or pes cavus based on the Foot Posture Index, arch index and normalised navicular height. Barefoot walking trials at a comfortable pace were conducted on a flat walkway. Foot kinematics were measured using a five-segment foot model to measure tri-planar motion of the rearfoot, midfoot, medial forefoot, lateral forefoot and hallux during. Plantar pressure and centre-of-pressure was measured via an emed®-x400 plantar pressure system (Novel GmbH, Munich, Germany). To describe plantar pressures, an 11-region mask including the medial heel, lateral heel, midfoot, 1st, 2nd, 3rd, 4th and 5th metatarsophalangeal joints, hallux, 2nd toe, and the 3rd, 4th and 5th toes was used. Peak pressure, pressure-time integral, maximum force, force-time integral and contact area were calculated for each region. For centre of pressure (COP), average, maximum, minimum and range (difference between maximum and minimum) values were calculated for COP velocity and lateral-medial force index during loading response, midstance, terminal stance and pre-swing phases of stance. One-way analyses of variance and effect sizes were used to compare the three foot posture groups.
Results: Most differences were found between planus and cavus feet. The largest effect sizes for each biomechanical analysis were related to the following findings. For kinematics, cavus feet displayed less transverse plane motion of the midfoot compared to planus feet. For plantar pressures, planus feet displayed greater peak pressures at the 4th and 5th metatarsophalangeal joints compared to cavus feet. While for the COP, cavus feet displayed a slower velocity of the COP during terminal stance compared to planus feet.
Conclusions: Variations in foot posture are associated with differences in kinematic, plantar pressure and COP variables when walking. Each foot posture displayed unique biomechanical characteristics, but there is little evidence of a dose-response relationship for biomechanical variables across the spectrum of foot postures. There is adequate biomechanical evidence to suggest that foot posture, measured with reliable measurement tools, is a relevant clinical consideration. However, further research is required to explore the relationship between the biomechanical factors and the development of symptoms.
O10 Foot pain in the community: A cross-sectional study
Jerneja Uhan
Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford
Purpose: The reported prevalence of foot and ankle pain in the general population is variable, ranging from 16% to 80%. In the UK, the estimated foot pain prevalence of 23% accounts for 8% of General practitioners’ caseloads. Possible associated problems include impaired balance, increased risk of falling, decreased activity, and reduced independence. This study aimed to describe the prevalence of self-reported foot pain in a UK population-based cohort.
Methods: A cross-sectional study design was undertaken, whereby a sample of women and men from the general population recruited from an established cohort, who had completed foot health postal questionnaires were investigated for self-reported foot pain. Participants answered NHANES-based questions including “Have you ever experienced foot pain?” and “Have you experienced pain in the last month?” The available responses included: no; yes, left foot only; yes, right foot only; yes, both feet; yes, not sure what side; and unknown, and a diagram of the feet was provided, for those with foot pain to mark its location. The Manchester Foot Pain and Disability Index-17 (MFPDI) was also used. Descriptive statistics were used to rank the most common answers to MFPDI by sex, and the Chi-squared test was used for analysing BMIs.
Results: From 1000 participants, we reviewed data from a sample of 188 participants (103 women, 85 men; mean age 64.2 (range 31–84) for whom foot pain data were complete. BMIs did not differ significantly between men and women (28.2 vs 28.5, p=0.304), and 61% (n=52) of men and 69% (n=31) of women worked in an occupation considered to have “high risk” for foot pain and osteoarthritis development. Prevalence of foot pain was higher in the midfoot than in the forefoot. Analysis of responses to “Have you ever experienced foot pain” indicated a lower prevalence of midfoot pain 31.0 % (n=18) vs 32.63% (n=14) and higher prevalence of 1st metatarsophalangeal joint pain 25.9% (n=15) vs 16.3% (n=7) in women than in men respectively. However, the response to “Have you experienced foot pain in last month” showed no differences in trends between women and men. The 4 most common responses in women to the MFPDI’s 17 questions were: “My feet are worse in the morning” (21.4%); “My feet are more painful in the evening” (19.4%); “I still do everything but with more pain and discomfort” (16.5%); and “I avoid hard or rough surfaces when possible” (15.5%). For men, the 4 most common responses were: “I get shooting pains in my feet” (25.9%); “I have constant pain in my feet” (23.5%); “I still do everything but with more pain and discomfort” (22.4%); and “my feet are worse in the morning” (15.3%).
Conclusions: The prevalence of foot pain was similar in women and men and predominantly affected the midfoot and forefoot which accords with previous studies. Although, there is the need for future studies to investigate foot pain, with regards to its association with individual foot joint level osteoarthritis, in order to further optimise intervention strategies.
O11 The development of a new patient centred approach to improve insole adherence amongst people with diabetes
Joanne Paton
Faculty of Health: Medicine, Dentistry and Human Sciences, School of Health Professions, University of Plymouth
Background: Insoles are only effective in protecting feet against diabetic foot ulceration when worn. Research investigating insole adherence in people with diabetes infers that people are disregarding the advice to wear insoles all day every day. Insole adherence must improve if diabetic foot ulceration is to reduce.
Aim: Develop a logic model describing the active ingredients, underpinning theories, and outcomes of a complex intervention to build patient motivation for diabetic foot ulcer protection using insoles.
Methods: The development stage of the Medical Research Council Framework (2), NICE guidance on Behaviour change (4): individual approaches, and the Behaviour Change Wheel (3) provided the development framework for the logic model (1). Methods included; a review of epidemiology research about diabetic foot ulceration and risk factors. Our own empirical clinical trial data demonstrating poor insole adherence (5). Semi structured interviews with patients to determine drivers for none-adherence and theorise the problem(6-8). Two patient workshops to understand what needed to change and how. Expert input from a clinical psychologist and podiatrist with context experience of current NHS diabetic foot care systems.
Results: Defined outcomes were incidence of diabetic foot ulceration and habituation for wearing insoles. People moderated insole usage depending on a personal appraisal of insole benefit and fit within a social context. Patient needs are not listened too or met by the clinicians providing insoles. The intervention has three components; patient empowerment (motivational interviewing), positive thinking and action planning (Functional Imagery Training) and increased understanding (visual biofeedback) using four behaviour change techniques: Education, incentivisation, persuasion, and enablement.
References
1. Conrad K.J. (1999) Creating and using logic models: Four perspectives. Homelessness Prevention in Treatment of Substance Abuse. 17-31
2. Craig P. (2006) Developing and evaluating complex interventions: new guidance. MRC.
3. Mitie S. (2011) The behaviour change wheel: A new method for characterising and designing behaviour change interventions. Implementation Science. 6 (42) 1-11.
4. NICE ph49 (2014) Behaviour Change: Individual approaches. National Institute for Health and Care Excellence.
5. Paton J. (2012) A comparison of functional and prefabricated insoles used for the preventative management of neuropathic diabetic foot ulceration: a single blind randomised control trial. JFAR. http://www.jfootankleres.com/content/5/1/31
6. Paton J. (2013) Does footwear affect balance? the views and experiences of people with diabetes who have fallen. JAPMA. 103 (6), 508-515.
7. Paton J. (2014) Patients’ Experience of therapeutic footwear whilst living at risk of neuropathic diabetic foot ulceration: an interpretative phenomenological analysis (IPA). JFAR. 7. 16. doi:10.1186/1757-1146-7-16.
8. Paton J. (2014) “All I wanted was a pair of shoes”: A qualitative case study. 2014. The Diabetic Foot Journal 17(3), 28-32.
O12 A 12mm, in shoe orthotic heel lift added to standard running shoes, lowers Achilles tendon loading
Simon Bartold
Centre for Health, Exercise and Sports Medicine, University of Melbourne, Melbourne, Australia
Background: Orthotic heel lifts are thought to lower tension in the Achilles tendon, but evidence for this effect is equivocal.
Objective: To investigate the effect of a 12- mm, in-shoe orthotic heel lift on Achilles tendon loading during shod walking using transmission mode ultrasonography.
Methods: The propagation speed of ultrasound, which is governed by the elastic modulus and density of tendon and proportional to the tensile load to which it is exposed, was measured in the right Achilles tendon of 12 recreationally active men during shod treadmill walking at matched speeds (3.4 • 0.7 km/h), with and without addition of a heel lift. Vertical ground reaction force and spatiotemporal gait parameters were simultaneously recorded. Data were acquired at 100 hz during 10 seconds of steady-state walking.
Statistical comparisons were made using paired t-Tests (α = .05).
Results: Ultrasound transmission speed in the Achilles tendon was characterized by 2 maxima (P1, P2) and minima (M1, M2) during walking. Addition of a heel lift to footwear resulted in a 2% increase and 2% decrease in the first vertical ground reaction force peak and the local minimum, respectively (P<.05). Ultrasonic velocity in the Achilles tendon (P1, P2, M2) was significantly lower with the addition of an orthotic heel lift (P<.05).
Conclusion: Peak ultrasound transmission speed in the Achilles tendon was lower with the addition of a 12-mm orthotic heel lift, indicating that the heel lift reduced tensile load in the Achilles tendon, thereby counteracting the effect of footwear observed in previous studies. These findings support the addition of orthotic heel lifts to footwear in the rehabilitation of Achilles tendon disorders where management aims to lower tension within the tendon.
O13 Comparative effectiveness of foot orthoses and corticosteroid injection for plantar heel pain: The soothe randomised trial
Glen Whittaker
Discipline of Podiatry School of Allied Health, La Trobe University, Melbourne, Australia
Objectives: To compare the effectiveness of foot orthoses and corticosteroid injection for plantar heel pain.
Design: A parallel-group, assessor-blinded randomised trial with a 12 week follow-up.
Setting: A single primary care podiatry centre at a university.
Participants: A total of 103 participants aged 21 to 72 years (63 female) with plantar heel pain were recruited from the community and received an intervention.
Interventions: Participants received a pair of prefabricated, arch-contouring foot orthoses (to wear as often as possible for the duration of the trial) or a single ultrasound-guided corticosteroid injection. All participants also received education and a stretching program for the plantar fascia and calf muscles.
Main outcome measures: The primary outcome measure was the foot pain subscale of the Foot Health Status Questionnaire at 4 and 12 weeks. Secondary outcome measures included ‘first step’ pain, foot function, overall improvement, health-related quality of life, fear-avoidance beliefs, self-reported physical activity, and thickness and hypoechogenicity of the plantar fascia measured using ultrasound.
Results: For the primary outcome measure of foot pain, corticosteroid injection was more effective at week 4 (adjusted mean difference 8.2 points, 95% CI 0.6 to 15.8). However, foot orthoses were more effective at week 12 (adjusted mean difference 8.5 points, 95% CI 0.2 to 16.8). Although these findings were statistically significant, they did not meet the previously calculated minimal important difference value of 12.5 points. There were no differences for secondary outcomes at any time-point, except for global perceived rating of change at week 4, which favoured corticosteroid injection (relative benefit increase 18%, 95% CI 3 to 36%; absolute benefit increase 15%, 95% CI 2 to 28%; number needed to treat 7, 95% CI 4 to 44).
Conclusions: Corticosteroid injection was found to be more effective than foot orthoses at reducing the primary outcome of foot pain at week 4. However, the superior effectiveness of corticosteroid injection was not sustained, and foot orthoses were more effective at reducing foot pain at week 12. The pain reductions observed may not be sufficiently worthwhile for some people, as they did not meet previously calculated minimal important difference values. Nevertheless, to achieve both short- and longer-term pain relief, both corticosteroid injection and arch contouring foot orthoses are effective for treating plantar heel pain.
O14 Influence of pre-fabricated medially posted foot orthoses on kinematics, kinetics and muscle activation in healthy individuals
Sarah Curran1, Bonifácio D2, Richards J3, Selfe J4, Curran S4, Trede R5
1School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, UK;2 Postgraduate Program in Rehabilitation and Functional Performance, UFVJM, Diamantina, Brazil; 3Allied Health Research Unit, University of Central Lancashire, Preston, UK; 4Department of Health Professions, Faculty of Health, Psychology and Social Care, Manchester Metropolitan University, Manchester, UK; 5Postgraduate Program in Rehabilitation and Functional Performance, UFVJM, Diamantina, Brazil
Background and Aim: Although a range of kinetics and kinematic parameters for the lower limb and use of foot orthoses is represented in the existing literature, limited information exists on the role of muscle function. To date little or no information is available on the effect of foot orthoses on the intrinsic muscles of the foot, which might help to explain the inconsistent findings with foot orthoses (1, 2). The purpose of this study was to compare lower limb mechanics and muscle activation during normal walking in three conditions: 5 degree medial rearfoot posting, 5 degree medial rearfoot and rearfoot posting, and a control flat insole.
Method: Kinematic and kinetic data were collected from the dominant lower limb and pelvis of sixteen healthy subjects (mean age 25.7 years) for each of condition. Electromyography (EMG) data was obtained from the tibialis anterior, peroneus longus muscle, medial gastrocnemius and abductor hallucis muscles. Repeated Measures ANOVAs with pairwise comparisons were performed to compare the three orthotic conditions.
Results: The medially posted conditions increased the knee adduction impulse suggesting a reduction of the knee dynamic valgus and a medialisation of the ground reaction force. Significant reductions in muscle activity were noted for the abductor hallucis iEMG for both sets of medial posted foot orthoses.
Conclusions: Both foot orthoses made significant changes in the knee and hip kinematics and kinetics, as well as changes to the muscle activity within the longitudinal arch of the foot when compared to no orthoses. Further pairwise comparisons revealed significant differences between the two foot orthoses only in the metatarsophalangeal sagittal plane range of motion and the knee adduction moment during late stance.
References
1. Mündermann, A, Wakeling, J.M, Nigg, B.M, Humble, R.N, and Stefanyshyn, D.J. (2006) Foot orthoses affect frequency components of muscle activity in the lower extremity. Gait Posture 23(3):295-302.
2. Murley, G.S, Landorf, K.B, Men, H.B. and Bird, A.R. (2009) Effect of foot posture, foot orthoses and footwear on lower limb muscle activity during walking and running: A systematic review. Gait Posture 29(2):172-187.