Utilization of smartphone and tablet camera photographs to predict healing of diabetes-related foot ulcers

The objective of this study was to build a machine learning model that can predict healing of diabetes-related foot ulcers, using both clinical attributes extracted from electronic health records (EHR) and image features extracted from photographs. The clinical information and photographs were collected at an academic podiatry wound clinic over a three-year period. Both hand-crafted color and texture features and deep learning-based features from the global average pooling layer of ResNet-50 were extracted from the wound photographs. Random Forest (RF) and Support Vector Machine (SVM) models were then trained for prediction. For prediction of eventual wound healing, the models built with hand-crafted imaging features alone outperformed models built with clinical or deep-learning features alone. Models trained with all features performed comparatively against models trained with hand-crafted imaging features. Utilization of smartphone and tablet photographs taken outside of research settings hold promise for predicting prognosis of diabetes-related foot ulcers.

Describing Normative Foot Temperatures in Patients With Diabetes-Related Peripheral Neuropathy

BACKGROUND

Prior research shows increased foot temperatures are predictive of diabetes-related foot complications. Our aim was to describe normative skin foot temperatures for individuals with diabetic peripheral neuropathy to better inform new technologies. We also explored for potential risk factors which correlate with changes in foot temperatures.

METHODS

We conducted a retrospective chart review of adult patients >18 years of age with diabetes mellitus and clinically diagnosed diabetic peripheral neuropathy with pedal digital thermometry performed between 2009 and 2018. A total of 58 patients met these criteria. Univariate modeling was based on covariates that may affect foot temperature including age, peripheral arterial disease, toe pressure, seasonality of measurement, smoking pack-years, caffeine use, insulin use, and calcium channel blocker use.

RESULTS

In patients with diabetic peripheral neuropathy, mean toe temperatures of 27.67°C (6.300°C), forefoot of 28.58°C (5.36°C), midfoot of 29.21°C (3.81°C), and rearfoot of 29.88°C(3.83°C) were demonstrated. A modest negative correlation between seasonality and toe and metatarsal temperatures (r = -0.38, P < .05; r = -0.43 P < .01, respectively) was demonstrated. Midfoot temperatures were modestly and positively correlated to the presence of small fiber symptoms (r = 0.33, P = .03). Positive modest correlation with rearfoot temperatures and amount of pack-year history (r = 0.30, P = .03) was seen.

CONCLUSION

Normative foot temperatures in neuropathic patients were found to be inversely associated with seasonality at the toe and metatarsal level. Smoking and pack-year history demonstrate modest correlation previously unseen in temperature analyses and warrant further exploration. Normative temperatures in neuropathic patients can better inform new technologies for the prevention of diabetic foot ulcer and Charcot neuroarthropathy.

Plantar fasciitis in patients with type 1 and type 2 diabetes: A contemporary cohort study

OBJECTIVE

Hyperglycemia leads to increase advanced glycation end products (AGEs) in patients with type 1 and type 2 diabetes. Subsequently, formation of AGEs can cause increased plantar fascial thickness (PFT), an imaging feature of plantar fasciitis (PF). This study evaluates the prevalence of PF in a contemporary cohort of type 1 diabetes and type 2 diabetes patients managed according to current standards, compared to patients without diabetes.

RESEARCH DESIGN AND METHODS

This is a five-year prevalence study in a large tertiary health system (approximately 535,000 patients/visits/year) with a single electronic medical record (EMR), applying a cohort discovery tool and database screen (Data Direct) with use of ICD-9 and ICD-10 codes. All patients with a PF diagnosis between 01/01/2011 and 01/01/2016 were included and divided into 3 groups: type 1 diabetes (7148 patients), type 2 diabetes (61,632 patients), and no diabetes (653,659 patients). Prevalence rates were calculated, accounting for other risk factors including BMI and gender using Fisher's exact test.

RESULTS

The overall prevalence of PF in the entire study population was 0.85%. Prevalence rates were higher in patients with diabetes, particularly with type 2 diabetes (42% and 64% higher compared with patients with type 1 diabetes and no diabetes respectively). Individually, PF rates were 0.92% in type 1 diabetes and 1.31% in type 2 diabetes compared with 0.80% in patients with no diabetes (Type 1 vs. no diabetes p = 0.26; Type 2 vs. no diabetes p ≪ 0.0001; Type 1 vs. Type 2 diabetes p = 0.0054). Females in all groups had higher prevalence of PF than males (p ≪ 0.0001 for all), with those patients with diabetes having higher prevalence rates than those without diabetes. Patients with higher BMI levels (BMI ≥ 30 kg/m²) were also more likely to have PF in all categories except males with type 1 diabetes (p = 0.40).

CONCLUSIONS

In this large contemporary population managed in a tertiary health system, prevalence rates of PF were substantially higher in patients with diabetes compared with no diabetes, particularly in type 2 diabetes. Female gender and higher BMI were also associated with higher prevalence of PF in this cohort.

A case of mistaken identity: classic Kaposi sarcoma misdiagnosed as a diabetic foot ulcer in an atypical patient

Background

The presentation of Kaposi sarcoma is divided into four known clinical subtypes. In this case report we describe classic Kaposi sarcoma in an African-American heterosexual, diabetic, seronegative human immunodeficiency virus male. Classic Kaposi sarcoma is rare in this patient demographic and can be easily misdiagnosed.

Case presentation

The patient presented with a lesion between the fourth and fifth digits of his right foot which was initially diagnosed as a diabetic foot ulcer. Despite local wound care, the lesion did not resolve. A shave biopsy was performed and histopathology findings were consistent with classic Kaposi sarcoma.

Conclusions

The patient tolerated local radiotherapy well and had complete resolution of his pedal lesion. There have been emerging associations between diabetes and Kaposi sarcoma. As such, clinicians should have a low threshold when considering the biopsy of suspicious pedal lesions in patients with diabetes. The utilization of appropriate biopsy technique may lead to the diagnosis of classic KS tumors in populations outside of the current four widely accepted clinical subtypes.

Prospective Analysis of Surgical Bone Margins After Partial Foot Amputation in Diabetic Patients Admitted With Moderate to Severe Foot Infections

BACKGROUND

Osteomyelitis is common in diabetic foot infections and medical management can lead to poor outcomes. Surgical management involves sending histopathologic and microbiologic specimens which guides future intervention. We examined the effect of obtainment of surgical margins in patients undergoing forefoot amputations to identify patient characteristics associated with outcomes. Secondary aims included evaluating interobserver reliability of histopathologic data at both the distal-to and proximal-to surgical bone margin.

METHODS

Data were prospectively collected on 72 individuals and was pooled for analysis. Standardized method to retrieve intraoperative bone margins was established. A univariate analysis was performed. Negative outcomes, including major lower extremity amputation, wound dehiscence, reulceration, reamputation, or death were recorded.

RESULTS

Viable proximal margins were obtained in 63 out of 72 cases (87.5%). Strong interobserver reliability of histopathology was recorded. Univariate analysis demonstrated preoperative platelets, albumin, probe-to-bone testing, absolute toe pressures, smaller wound surface area were associated with obtaining viable margins. Residual osteomyelitis resulted in readmission 2.6 times more often and more postoperative complications.

CONCLUSIONS

Certain patients were significantly different in the viable margin group versus dirty margin group. High interobserver reliability was demonstrated. Obtainment of viable margins resulted in reduced rates of readmission and negative outcomes.

LEVELS OF EVIDENCE

Prognostic, Level I: Prospective.

Podiatry impact on high-low amputation ratio characteristics: A 16-year retrospective study

PURPOSE

Complications from diabetes mellitus including major lower extremity amputation may have significant impact on a patient's mortality. This study determined what impact the addition of a limb salvage and diabetic foot program involving podiatry had at an academic institution over 16years by analyzing high-low amputation ratio data.

METHODS

The high-low amputation ratio in the diabetic population who underwent non-traumatic amputation of the lower extremity was retrospectively evaluated at an academic institution via cohort discovery of the electronic medical record and analysis of billing over 16years.

RESULTS

We directly compared two eras, one without podiatry and one with a podiatry presence. It was found that with the addition of a podiatry program, limb salvage rates significantly increased (R² (without podiatry)=0.45, R² (with podiatry)=0.26), with a significant change in both the rate of limb salvage per year (-0.11% per year versus -0.36% per year; p<0.01) and an overall decrease in high-low amputation ratio (0.89 without podiatry to 0.60 with podiatry). Of note, approximately 40 major lower extremity amputations were avoided per year with the addition of a podiatry program (p<0.05).

CONCLUSIONS

Our findings signify the importance of podiatric care in the diabetic population. With an established podiatry program present at an academic institution, major lower extremity amputations can be avoided and more limbs can be salvaged, thus preventing some of the moribund complications from this condition.

Physician knowledge of a rare foot condition - influence of diabetic patient population on self-described knowledge and treatment

Background

Charcot neuroarthopathy (CN), a rare foot and ankle condition usually complicating diabetes mellitus, leads to deformity, poor quality of life, and increased mortality and morbidity. The prevalence of this condition in the diabetic patient population is not currently known but has been reportedly misdiagnosed in up to 95% of cases.

Methods

We sought to evaluate general knowledge regarding CN in non-foot specialist clinical faculty at a large academic institution and to understand their practice habits. Our survey emphasizes the necessity of better education surrounding CN to improve outcomes in a preventative fashion. This will enable us to determine how to focus educational forums surrounding this topic in the future.

Results

Seven hundred eighty-nine faculty members were sent the survey while 400 completed the survey for a response rate of 50.7%. The respondents were representative of academic rank at the institution and were comprised of endocrinologists, internal medicine physicians and family medicine physicians. We found that 67.6% of responders had a self-described poor or complete lack of knowledge of this condition. Clinicians with self-described better knowledge of CN were more likely to provide a correct initial management of CN (p < 0.001; r = 0.3639).

Conclusions

In this large tertiary institution, a majority of providers among internal medicine, endocrinologists, and family medicine physicians demonstrated minimal or no knowledge of this rare, but potentially devastating diabetes complication. However, those providers who are knowledgeable of CN, performed better in the initial management of this condition. Also, respondents who treated more diabetic patients demonstrated an association with correct management. Education, and the development of better understanding amongst clinicians, is crucial to limit the devastating effects of this condition in the future.

Electronic supplementary material

The online version of this article (doi:10.1186/s40842-017-0041-4) contains supplementary material, which is available to authorized users.

Bizarre parosteal osteochondromatous proliferation: a novel case report of recurrence in the toe

Bizarre parosteal osteochondromatous proliferation (BPOP) is an uncommon reactive mesenchymal lesion mainly affecting the small bones of the hands and feet. They frequently occur in young adults. It is important to understand and differentiate BPOP from other lesions, especially because of its atypical microscopic features and tendency to recur. We present a case of a recurrent lesion involving the toe and discuss management options. To our knowledge, our current case report is the first in the literature to report a recurring BPOP lesion of the toe.

Recognizing the prevalence of changing adult foot size: an opportunity to prevent diabetic foot ulcers?

Ill-fitting shoes may precipitate up to half of all diabetes-related amputations and are often cited as a leading cause of diabetic foot ulcers (DFU), with those patients being 5 to 10 times more likely to present wearing improperly fitting shoes. Among patients with prior DFU, those who self-select their shoe wear are at a three-fold risk for reulceration at 3 years versus those patients wearing prescribed shoes. Properly designed and fitted shoes should then address much of this problem, but evidence supporting the benefit of therapeutic shoe programs is inconclusive. The current study, performed in a male veteran population, is the first such effort to examine the prevalence and extent of change in foot length affecting individuals following skeletal maturity. Nearly half of all participants in our study experienced a ≥1 shoe size change in foot length during adulthood. We suggest that these often unrecognized changes may explain the broad use of improperly sized shoe wear, and its associated sequelae such as DFU and amputation. Regular clinical assessment of shoe fit in at-risk populations is therefore also strongly recommended as part of a comprehensive amputation prevention program.

Characteristics of High-Functioning Collaborations Between Primary Care and Podiatry in VHA Patient Aligned Care Teams

The key to high-functioning PACT/Podiatry teams rests with the quality of the communication between providers.

Foot Complications and Mortality: Results from Translating Research Into Action for Diabetes (TRIAD)

BACKGROUND

We sought to study the impact of foot complications on 10-year mortality independent of other demographic and biological risk factors in a racially and socioeconomically diverse managed-care population with access to high-quality medical care.

METHODS

We studied 6,992 patients with diabetes in Translating Research Into Action for Diabetes (TRIAD), a prospective observational study of diabetes care in managed care. Foot complications were assessed using administrative claims data. The National Death Index was searched for deaths across 10 years of follow-up (2000-2009).

RESULTS

Charcot's neuro-osteoarthropathy and diabetic foot ulcer with debridement were associated with an increased risk of mortality; however, the associations were not significant in fully adjusted models. Lower-extremity amputation (LEA) was associated with an increased risk of mortality in unadjusted (hazard ratio [HR], 3.21; 95% confidence interval [CI], 2.50-4.12) and fully adjusted (HR, 1.84; 95% CI, 1.28-2.63) models. When we examined the associations between LEA and mortality stratified by sex and race, risk was increased in men (HR, 1.96; 95% CI, 1.25-3.07), Hispanic individuals (HR, 5.17; 95% CI, 1.48-18.01), and white individuals (HR, 2.18; 95% CI, 1.37-3.47). In sensitivity analyses, minor LEA tended to increase the risk of mortality (HR, 1.48; 95% CI, 0.92-2.40), and major LEA was associated with a significantly higher risk of death at 10 years (HR, 1.89; 95% CI, 1.18-3.01).

CONCLUSIONS

In this managed-care population with access to high-quality medical care, LEA remained a robust independent predictor of mortality. The association was strongest in men and differed by race.

Charcot stage 0: A review and consideratons for making the correct diagnosis early

Charcot neuropathic osteoarthropathy (CN) is a rare disease (NIDDK, NIH Summary Report Charcot Workshop, 2008) that causes significant morbidity and mortality for affected patients. The disease can result in severe deformities of the foot and ankle that contribute to the development of ulcerations and amputations. Medical advances have failed to find ways to stop the progression of the disease. However, it is known that early detection of the CN has a substantial impact on patient outcomes. CN in the earliest stage is very difficult to recognize and differentiate from other similar presenting diseases. We intend to outline clinical considerations practitioners can use when evaluating a patient with early stage suspected CN.

Prognostic Value of Diagnostic Sonography in Patients With Plantar Fasciitis

OBJECTIVES

The primary objective of this study was to determine whether the sonographic appearance of the plantar fascia is predictive of the treatment (ie, pain) response in patients receiving supportive therapy for proximal plantar fasciitis. This study was a secondary analysis of data obtained from a randomized controlled trial of ambulatory adults, which examined the efficacy of 3 different foot supports for plantar fasciitis.

METHODS

Participants underwent diagnostic sonographic examinations of their heel at baseline and again at 3 months by a single experienced foot and ankle surgeon. Quantitative (eg, thickness) and qualitative (eg, biconvexity) characteristics of the fascia were recorded according to a standard protocol. Logistic regression models were used to identify predictors of the pain response.

RESULTS

Seventy patients completed a baseline evaluation, and 63 patients completed a 3-month follow-up assessment. The pain response was not associated with the type of foot support (P> .05). The only significant indicator of an unfavorable response in the univariate and multivariate analyses was biconvexity of the plantar fascia on sonography at presentation (multivariate odds ratio, 4.76 [95% confidence interval, 1.16-19.5; P= .030). Furthermore, changes in self-reported pain over the 3-month study period were not accompanied by alterations in plantar fascia thickness over this time (r = .056; P = .671).

CONCLUSIONS

We conclude that patients who present with biconvexity of the plantar fascia may be less responsive to tier 1 treatment regimens that center around mechanical support of the plantar fascia. Furthermore, follow-up measurements of the fascia in this population should not weigh heavily in decisions such as return to play.

Physical Examination Variables Predict Response to Conservative Treatment of Nonchronic Plantar Fasciitis: Secondary Analysis of a Randomized, Placebo-Controlled Footwear Study

BACKGROUND

Plantar fasciitis is a common, disabling condition, and the prognosis of conservative treatment is difficult to predict.

OBJECTIVE

To determine whether initial clinical findings could help predict patient response to conservative treatment that primarily consisted of supportive footwear and stretching.

SETTING

Patients were recruited and seen at 2 outpatient podiatric clinics in the Chicago, Illinois, metropolitan area.

PATIENTS

Seventy-seven patients with nonchronic plantar fasciitis were recruited. Patients were excluded if they had a heel injection in the previous 6 months or were currently using custom foot orthoses at the time of screening. Sixty-nine patients completed the final follow-up visit 3 months after receiving the footwear intervention.

METHODS

Treatment failure was considered a <50% reduction in heel pain at 3 month follow-up. Logistic regression models evaluated the possible association between more than 30 clinical and physical examination findings prospectively assessed at enrollment, and treatment response.

RESULTS

Inability to dorsiflex the ankle past -5° (odds ratio [OR] 3.9, P = .024), nonsevere (≤7 on ordinal scale) first-step pain (OR 3.8, P = .021), and heel valgus in relaxed stance (OR 4.0, P = .014) each predicted treatment failure in multivariable analysis (receiver operating characteristic area under the curve = .769). Limited ankle dorsiflexion also correlated with greater heel pain severity at initial presentation (r = - 0.312, P = .006).

CONCLUSIONS

Patients with severe ankle equinus were nearly 4 times more likely to experience a favorable response to treatment centered on home Achilles tendon stretching and supportive therapy. Thus, earlier use of more advanced therapies may be most appropriate in those presenting without severe ankle equinus or without severe first step pain. The findings from our study may not be clinically intuitive because patients with less severe equinus and less severe pain at presentation did worse with conservative care.

A randomized controlled trial of custom foot orthoses for the treatment of plantar heel pain

BACKGROUND

Up to 10% of people will experience heel pain. The purpose of this prospective, double-blind, randomized clinical trial was to compare custom foot orthoses (CFO), prefabricated foot orthoses (PFO), and sham insole treatment for plantar fasciitis.

METHODS

Seventy-seven patients with plantar fasciitis for less than 1 year were included. Outcome measures included first step and end of day pain, Revised Foot Function Index short form (FFI-R), 36-Item Short Form Health Survey (SF-36), activity monitoring, balance, and gait analysis.

RESULTS

The CFO group had significantly improved total FFI-R scores (77.4 versus 57.2; P = .03) without group differences for FFI-R pain, SF-36, and morning or evening pain. The PFO and CFO groups reported significantly lower morning and evening pain. For activity, the CFO group demonstrated significantly longer episodes of walking over the sham (P = .019) and PFO (P = .03) groups, with a 125% increase for CFOs, 22% PFOs, and 0.2% sham. Postural transition duration (P = .02) and balance (P = .05) improved for the CFO group. There were no gait differences. The CFO group reported significantly less stretching and ice use at 3 months.

CONCLUSIONS

The CFO group demonstrated 5.6-fold greater improvements in spontaneous physical activity versus the PFO and sham groups. All three groups improved in morning pain after treatment that included standardized athletic shoes, stretching, and ice. The CFO changes may have been moderated by decreased stretching and ice use after 3 months. These findings suggest that more objective measures, such as spontaneous physical activity improvement, may be more sensitive and specific for detecting improved weightbearing function than traditional clinical outcome measures, such as pain and disease-specific quality of life.

Estimation of Center of Mass Trajectory using Wearable Sensors during Golf Swing

This study suggests a wearable sensor technology to estimate center of mass (CoM) trajectory during a golf swing. Groups of 3, 4, and 18 participants were recruited, respectively, for the purpose of three validation studies. Study 1 examined the accuracy of the system to estimate a 3D body segment angle compared to a camera-based motion analyzer (Vicon®). Study 2 assessed the accuracy of three simplified CoM trajectory models. Finally, Study 3 assessed the accuracy of the proposed CoM model during multiple golf swings. A relatively high agreement was observed between wearable sensors and the reference (Vicon®) for angle measurement (r > 0.99, random error <1.2° (1.5%) for anterior-posterior; <0.9° (2%) for medial-lateral; and <3.6° (2.5%) for internal-external direction). The two-link model yielded a better agreement with the reference system compared to one-link model (r > 0.93 v. r = 0.52, respectively). On the same note, the proposed two-link model estimated CoM trajectory during golf swing with relatively good accuracy (r > 0.9, A-P random error <1cm (7.7%) and <2cm (10.4%) for M-L). The proposed system appears to accurately quantify the kinematics of CoM trajectory as a surrogate of dynamic postural control during an athlete's movement and its portability, makes it feasible to fit the competitive environment without restricting surface type. Key pointsThis study demonstrates that wearable technology based on inertial sensors are accurate to estimate center of mass trajectory in complex athletic task (e.g., golf swing)This study suggests that two-link model of human body provides optimum tradeoff between accuracy and minimum number of sensor module for estimation of center of mass trajectory in particular during fast movements.Wearable technologies based on inertial sensors are viable option for assessing dynamic postural control in complex task outside of gait laboratory and constraints of cameras, surface, and base of support.

A novel shear reduction insole effect on the thermal response to walking stress, balance, and gait

Shear stresses have been implicated in the formation of diabetes-related foot ulcers. The aim of this study was to evaluate the effect of a novel shear-reducing insole on the thermal response to walking, balance, and gait. Twenty-seven diabetes peripheral neuropathy patients were enrolled and asked to take 200 steps in both intervention and standard insoles. Thermal foot images of the feet were taken at baseline (1) following a 5-minute temperature acclimatization and (2) after walking. Testing order was randomized, and a 5-minute washout period was used between testing each insole condition. Sudomotor function was also assessed. Gait and balance were measured under single and dual task conditions using a validated body worn sensor system. The mean age was 65.1 years, height was 67.3 inches, weight was 218 pounds, and body mass index was 33.9, 48% were female, and 82% had type 2 diabetes. After walking in both insole conditions, foot temperatures increased significantly in standard insoles. The intervention insole significantly reduced forefoot and midfoot temperature increases (64.1%, P = .008; 48%, P = .046) compared to standard insoles. There were significant negative correlations with sudomotor function and baseline temperatures (r = .53-.57). The intervention demonstrated 10.4% less gait initiation double support time compared to standard insoles (P = .05). There were no differences in static balance measures. We found significantly lower forefoot and midfoot temperature increases following walking with shear-reducing insoles compared to standard insoles. We also found improvements in gait. These findings merit future study for the prevention of foot ulcer.

Association of footprint measurements with plantar kinetics: a linear regression model

BACKGROUND

The use of foot measurements to classify morphology and interpret foot function remains one of the focal concepts of lower-extremity biomechanics. However, only 27% to 55% of midfoot variance in foot pressures has been determined in the most comprehensive models. We investigated whether dynamic walking footprint measurements are associated with inter-individual foot loading variability.

METHODS

Thirty individuals (15 men and 15 women; mean ± SD age, 27.17 ± 2.21 years) walked at a self-selected speed over an electronic pedography platform using the midgait technique. Kinetic variables (contact time, peak pressure, pressure-time integral, and force-time integral) were collected for six masked regions. Footprints were digitized for area and linear boundaries using digital photo planimetry software. Six footprint measurements were determined: contact area, footprint index, arch index, truncated arch index, Chippaux-Smirak index, and Staheli index. Linear regression analysis with a Bonferroni adjustment was performed to determine the association between the footprint measurements and each of the kinetic variables.

RESULTS

The findings demonstrate that a relationship exists between increased midfoot contact and increased kinetic values in respective locations. Many of these variables produced large effect sizes while describing 38% to 71% of the common variance of select plantar kinetic variables in the medial midfoot region. In addition, larger footprints were associated with larger kinetic values at the medial heel region and both masked forefoot regions.

CONCLUSIONS

Dynamic footprint measurements are associated with dynamic plantar loading kinetics, with emphasis on the midfoot region.

Mechanism of orthotic therapy for the painful cavus foot deformity

Background

People who have extremely high arched feet or pes cavus often suffer from substantial foot pain. Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear. It is generally thought that one of the primary functions of CFO is redistributing abnormal plantar pressures. This study sought to identify variables associated with pain relief after CFO intervention.

Methods

Plantar pressure data from a randomized controlled trial of 154 participants with painful pes cavus were retrospectively re-analyzed at baseline and three month post CFO intervention. The participants were randomized to a treatment group given CFO or a control group given sham orthoses.

Results

No relationship between change in pressure magnitude and change in symptoms was found in either group. However, redistribution of plantar pressure, measured with the Dynamic Plantar Loading Index, had a significant effect on pain relief (p = 0.001). Our final model predicted 73% of the variance in pain relief from CFO and consisted of initial pain level, BMI, foot alignment, and changes in both Dynamic Plantar Loading Index and pressure–time integral.

Conclusion

Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures. Results of this study add to the growing body of literature providing mechanistic support for CFO providing pain relief in painful foot conditions. The proposed model may assist in better designing and assessing orthotic therapy for pain relief in patients suffering painful cavus foot deformity.

Trial registration

Randomized controlled trial: ISRCTN84913516

Data mining for identifying novel associations and temporal relationships with Charcot foot

INTRODUCTION. Charcot foot is a rare and devastating complication of diabetes. While some risk factors are known, debate continues regarding etiology. Elucidating other associated disorders and their temporal occurrence could lead to a better understanding of its pathogenesis. We applied a large data mining approach to Charcot foot for elucidating novel associations. METHODS. We conducted an association analysis using ICD-9 diagnosis codes for every patient in our health system (n = 1.6 million with 41.2 million time-stamped ICD-9 codes). For the current analysis, we focused on the 388 patients with Charcot foot (ICD-9 713.5). RESULTS. We found 710 associations, 676 (95.2%) of which had a P value for the association less than 1.0 × 10⁻⁵ and 603 (84.9%) of which had an odds ratio > 5.0. There were 111 (15.6%) associations with a significant temporal relationship (P < 1.0 × 10⁻³). The three novel associations with the strongest temporal component were cardiac dysrhythmia, pulmonary eosinophilia, and volume depletion disorder. CONCLUSION. We identified novel associations with Charcot foot in the context of pathogenesis models that include neurotrophic, neurovascular, and microtraumatic factors mediated through inflammatory cytokines. Future work should focus on confirmatory analyses. These novel areas of investigation could lead to prevention or earlier diagnosis.

Prevalence and risk factors for diabetes-related foot complications in Translating Research Into Action for Diabetes (TRIAD)

AIMS

The objective was to describe the prevalence of diabetes-related foot complications in a managed care population and to identify the demographic and biological risk factors.

METHODS

We assessed the period prevalence of foot complications on 6992 patients using ICD-9 diagnosis codes from health plan administrative data. Demographic and biological variables were ascertained from surveys and medical record reviews. We defined four mutually exclusive groups: any Charcot foot, DFU with debridement, amputation±DFU and debridement, and no foot conditions.

RESULTS

Overall, 55 (0.8%) patients had Charcot foot, 205 (2.9%) had DFU with debridement, and 101 (1.4%) had a lower-extremity amputation. There were 6631 patients with no prevalent foot conditions. Racial/ethnic minorities were less likely to have Charcot foot (OR=0.21; 95% CI: 0.10, 0.46) or DFU (OR=0.61; 95% CI: 0.44, 0.84) compared to non-Hispanic Whites, but there were no racial/ethnic differences in amputation. Histories of micro- or macrovascular disease were associated with a two- to four-fold increase in the odds of foot complications.

CONCLUSION

In managed care patients with uniform access to health care, we found a relatively high prevalence of foot complications, but attenuation of the racial/ethnic differences of rates reported in the literature.

The system of care for the diabetic foot: objectives, outcomes, and opportunities

Most cases of lower extremity limb loss in the United States occur among people with diabetes who have a diabetic foot ulcer (DFU). These DFUs and the associated limb loss that may occur lead to excess healthcare costs and have a large negative impact on mobility, psychosocial well-being, and quality of life. The strategies for DFU prevention and management are evolving, but the implementation of these prevention and management strategies remains challenging. Barriers to implementation include poor access to primary medical care; patient beliefs and lack of adherence to medical advice; delays in DFU recognition; limited healthcare resources and practice heterogeneity of specialists. Herein, we review the contemporary outcomes of DFU prevention and management to provide a framework for prioritizing quality improvement efforts within a resource-limited healthcare environment.

Predicting development of proliferative diabetic retinopathy

OBJECTIVE

Identifying individuals most at risk for diabetic retinopathy progression and intervening early can limit vision loss and reduce the costs associated with managing more advanced disease. The purpose of this study was to identify factors associated with progression from nonproliferative diabetic retinopathy (NPDR) to proliferative diabetic retinopathy (PDR).

RESEARCH DESIGN AND METHODS

This was a retrospective cohort analysis using a claims database of all eye care recipients age ≥ 30 years enrolled in a large managed-care network from 2001 to 2009. Individuals with newly diagnosed NPDR were followed longitudinally. Multivariable Cox regression analyses identified factors associated with progression to PDR. Three- and five-year probabilities of retinopathy progression were determined.

RESULTS

Among the 4,617 enrollees with incident NPDR, 307 (6.6%) developed PDR. After adjustment for confounders, every 1-point increase in HbA1c was associated with a 14% (adjusted hazard ratio 1.14 [95% CI 1.07-1.21]) increased hazard of developing PDR. Those with nonhealing ulcers had a 54% (1.54 [1.15-2.07]) increased hazard of progressing to PDR, and enrollees with nephropathy had a marginally significant increased hazard of progressing to PDR (1.29 [0.99-1.67]) relative to those without these conditions. The 5-year probability of progression for low-risk individuals with NPDR was 5% (range 2-8) and for high-risk patients was 38% (14-55).

CONCLUSIONS

Along with glycemic control, nonophthalmologic manifestations of diabetes mellitus (e.g., nephropathy and nonhealing ulcers) are associated with an increased risk of diabetic retinopathy progression. Our retinopathy progression risk score can help clinicians stratify patients who are most at risk for disease progression.

An apparatus to quantify anteroposterior and mediolateral shear reduction in shoe insoles

BACKGROUND

Many of the physiological changes that lead to diabetic foot ulceration, such as muscle atrophy and skin hardening, are manifested at the foot-ground interface via pressure and shear points. Novel shear-reducing insoles have been developed, but their magnitude of shear stiffness has not yet been compared with regular insoles. The aim of this study was to develop an apparatus that would apply shear force and displacement to an insole's forefoot region, reliably measure deformation, and calculate insole shear stiffness.

METHODS

An apparatus consisting of suspended weights was designed to test the forefoot region of insoles. Three separate regions representing the hallux; the first and second metatarsals; and the third, fourth, and fifth metatarsals were sheared at 20 mm/min for displacements from 0.1 to 1.0 mm in both the anteroposterior and mediolateral directions for two types of insoles (regular and shear reducing).

RESULTS

Shear reduction was found to be significant for the intervention insoles under all testing conditions. The ratio of a regular insole's effective stiffness and the experimental insole's effective stiffness across forefoot position versus shear direction, gait instance versus shear direction, and forefoot position versus gait instance was 270% ± 79%, 270% ± 96%, and 270% ± 86%, respectively. The apparatus was reliable with an average measured coefficient of variation of 0.034 and 0.069 for the regular and shear-reducing insole, respectively.

CONCLUSION

An apparatus consisting of suspended weights resting atop three locations of interest sheared across an insole was demonstrated to be capable of measuring the insole shear stiffness accurately, thus quantifying shear-reducing effects of a new type of insole.

Podiatrist care and outcomes for patients with diabetes and foot ulcer

We examined whether outcomes of care (amputation and hospitalisation) among patients with diabetes and foot ulcer differ between those who received pre-ulcer care from podiatrists and those who did not. Adult patients with diabetes and a diagnosis of a diabetic foot ulcer were found in the MarketScan Databases, 2005-2008. Multivariate Cox proportional hazard models estimated the hazard of amputation and hospitalisation. Logistic regression estimated the likelihood of these events. Propensity score weighting and regression adjustment were used to adjust for potentially different characteristics of patients who did and did not receive podiatric care. The sample included 27 545 patients aged greater than 65+ years (Medicare-eligible patients with employer-sponsored supplemental insurance) and 20 208 patients aged lesser than 65 years (non Medicare-eligible commercially insured patients). Care by podiatrists in the year prior to a diabetic foot ulcer was associated with a lower hazard of lower extremity amputation, major amputation and hospitalisations in both non Medicare-eligible commercially insured and Medicare-eligible patient populations. Systematic differences between patients with diabetes and foot ulcer, receiving and not receiving care from podiatrists were also observed; specifically, patients with diabetes receiving care from podiatrists tend to be older and sicker.

Collagen-based wound dressings for the treatment of diabetes-related foot ulcers: a systematic review

BACKGROUND

Diabetic foot ulcers are a major source of morbidity, limb loss, and mortality. A prolonged inflammatory response, extracellular matrix degradation irregularities, and increased bacteria presence have all been hypothesized as major contributing factors in the delayed healing of diabetic wounds. Collagen components such as fibroblast and keratinocytes are fundamental to the process of wound healing and skin formation. Wound dressings that contain collagen products create a biological scaffold matrix that supports the regulation of extracellular components and promotes wound healing.

METHODS

A systematic review of studies reporting collagen wound dressings used in the treatment of Diabetic foot ulcers was conducted. Comprehensive searches were run in Ovid MEDLINE, PubMed, EMBASE, and ISI Web of Science to capture citations pertaining to the use of collagen wound dressings in the treatment of diabetic foot ulcers. The searches were limited to human studies reported in English.

RESULTS

Using our search strategy, 26 papers were discussed, and included 13 randomized designs, twelve prospective cohorts, and one retrospective cohort, representing 2386 patients with diabetic foot ulcers. Our design was not a formal meta-analysis. In those studies where complete epithelialization, 58% of collagen-treated wounds completely healed (weighted mean 67%). Only 23% of studies reported control group healing with 29% healing (weighted mean 11%) described for controls.

CONCLUSION

Collagen-based wound dressings can be an effective tool in the healing of diabetic foot wounds. The current studies show an overall increase in healing rates despite limitations in study designs. This study suggests that future works focus on biofilms and extracellular regulation, and include high risk patients.

Retinal spectral domain optical coherence tomography in early atrophic age-related macular degeneration (AMD) and a new metric for objective evaluation of the efficacy of ocular nutrition

Purpose: A challenge in ocular preventive medicine is identification of patients with early pathological retinal damage that might benefit from nutritional intervention. The purpose of this study is to evaluate retinal thinning (RT) in early atrophic age-related macular degeneration (AMD) against visual function data from the Zeaxanthin and Visual Function (ZVF) randomized double masked placebo controlled clinical trial (FDA IND #78973). Methods: Retrospective, observational case series of medical center veterans with minimal visible AMD retinopathy (AREDS Report #18 simplified grading 1.4/4.0 bilateral retinopathy). Foveal and extra-foveal four quadrant SDOCT RT measurements were evaluated in n = 54 clinical and ZVF AMD patients. RT by age was determined and compared to the OptoVue SD OCT normative database. RT by quadrant in a subset of n = 29 ZVF patients was correlated with contrast sensitivity and parafoveal blue cone increment thresholds. Results: Foveal RT in AMD patients and non-AMD patients was preserved with age. Extrafoveal regions, however, showed significant slope differences between AMD patients and non-AMD patients, with the superior and nasal quadrants most vulnerable to retinal thinning (sup quad: −5.5 μm/decade thinning vs. Non-AMD: −1.1 μm/decade, P < 0.02; nasal quad: −5.0 μm/decade thinning vs. Non-AMD: −1.0 μm/decade, P < 0.04). Two measures of extrafoveal visual deterioration were correlated: A significant inverse correlation between % RT and contrast sensitivity (r = −0.33, P = 0.01, 2 Tailed Paired T) and an elevated extrafoveal increment blue cone threshold (r = +0.34, P = 0.01, 2 Tailed T). Additional SD OCT RT data for the non-AMD oldest age group (ages 82–91) is needed to fully substantiate the model. Conclusion: A simple new SD OCT clinical metric called “% extra-foveal RT” correlates well with functional visual loss in early AMD patients having minimal visible retinopathy. This metric can be used to follow the effect of repleting ocular nutrients, such as zinc, antioxidants, carotenoids, n-3 essential fats , resveratrol and vitamin D.

Golfing skill level postural control differences: a brief report

Golfers have better balance than their age-matched counterparts; however, it is uncertain if this persists during the swing as a function of skill level. The purpose of the study was to investigate dynamic postural control (center of mass (COM) motion) measured during different phases of the swing in golfers of varying proficiency. Eighteen healthy golfers were grouped by handicap: novice (no handicap, n = 7), intermediate (handicap 15-19, n = 7), and advanced (handicap 9-14, n = 4). Indoor testing was performed hitting 3 tee shots using a common driver. A five-camera (60 Hz) motion analysis system (9 markers) was used to extract kinematics data. There were no significant group differences in gender, age, or BMI. Advanced players had lower COM displacement with respect to address at the time of maximum arm speed (p = 0. 001) compared to intermediate (57%, p = 0.014) and novice (73%, p = 0.023). These changes persisted after COM distance and time normalization. Advanced golfers had improved COM linearity during the downswing (p < 0.001) compared to intermediate (30%, p = 0.029) and novice (51%, p < 0.001). Advanced players had decreased COM displacement at the time of maximum arm speed and a more linear COM path during the early downswing. Further study should focus on these changes during ball launch conditions. Key pointsStudies suggest that static and dynamic balance is important in golf. However, none have investigated dynamic postural control during the golf swing in golfers of varying proficiency.Our findings suggest advanced players demonstrated improved postural control at the point of maximum arm speed when compared to less skilled players. Furthermore, center of mass acceleration in advanced players is closer to impact than less-skilled players.We observed an increased center of mass linearity of trajectory during the early downswing for advanced players over novice players. We theorized this strategy may help advanced golfers to improve the economy of COM motion during golf swing and improve the performance of the shot.

Dynamic footprint measurement collection technique and intrarater reliability: ink mat, paper pedography, and electronic pedography

BACKGROUND

Identifying the variability of footprint measurement collection techniques and the reliability of footprint measurements would assist with appropriate clinical foot posture appraisal. We sought to identify relationships between these measures in a healthy population.

METHODS

On 30 healthy participants, midgait dynamic footprint measurements were collected using an ink mat, paper pedography, and electronic pedography. The footprints were then digitized, and the following footprint indices were calculated with photo digital planimetry software: footprint index, arch index, truncated arch index, Chippaux-Smirak Index, and Staheli Index. Differences between techniques were identified with repeated-measures analysis of variance with post hoc test of Scheffe. In addition, to assess practical similarities between the different methods, intraclass correlation coefficients (ICCs) were calculated. To assess intrarater reliability, footprint indices were calculated twice on 10 randomly selected ink mat footprint measurements, and the ICC was calculated.

RESULTS

Dynamic footprint measurements collected with an ink mat significantly differed from those collected with paper pedography (ICC, 0.85-0.96) and electronic pedography (ICC, 0.29-0.79), regardless of the practical similarities noted with ICC values (P = .00). Intrarater reliability for dynamic ink mat footprint measurements was high for the footprint index, arch index, truncated arch index, Chippaux-Smirak Index, and Staheli Index (ICC, 0.74-0.99).

CONCLUSIONS

Footprint measurements collected with various techniques demonstrate differences. Interchangeable use of exact values without adjustment is not advised. Intrarater reliability of a single method (ink mat) was found to be high.

Dynamic plantar loading index: understanding the benefit of custom foot orthoses for painful pes cavus

The purpose of this study was to evaluate a new method showing how custom foot orthoses (CFO) improve dynamics of plantar loading. The method is based on the probability distribution of peak pressure time series and is quantified using the Regression Factor (RF). RF is a least square regression slope between the experimentally observed plantar pressure magnitude probability distribution and a modeled Gaussian shape. Plantar pressure data from a randomized controlled trial of 154 participants with painful Pes Cavus were retrospectively re-analyzed. The participants were randomized to an active treatment group given CFO or a control group given sham orthoses. The location of 2(nd) Peak pressure as a percentage of stance time (P(Loc2)) and its magnitude (P(M2)) was also calculated. In addition, plantar pressure data were collected on 23 healthy volunteers with normal foot alignment and no foot pain. Results demonstrated Pes Cavus had a significantly lower RF than healthy participants (0.30 v. 0.51; p<10(-7)). P(M2) was reduced in both active and control groups. However, RF and the P(Loc2) were only changed in the active group (p<0.005) without any significant change in the control group (p>0.5). This study suggests that painful Pes Cavus alters the shape of probability distribution of plantar loading during walking and CFO are an effective therapeutic solution that can significantly improve it. Further use of the RF index and 2(nd) peak pressure location as an outcome measure for treatment of foot and ankle deformities is suggested.

Does open access improve the process and outcome of podiatric care?

Background

Open access to clinics is a management strategy to improve healthcare delivery. Providers are sometimes hesitant to adopt open access because of fear of increased visits for potentially trivial complaints. We hypothesized open access clinics would result in decreased wait times, increased number of podiatry visits, fewer “no shows”, higher rates of acute care visits, and lower minor amputation rates over control clinics without open access.

Methods

This study was a national retrospective case-control study of VHA (Veterans Hospital Administration) podiatry clinics in 2008. Eight case facilities reported to have open podiatry clinic access for at least one year were identified from an email survey. Sixteen control facilities with similar structural features (e.g., full time podiatrists, health tech, residency program, reconstructive foot surgery, vascular, and orthopedic surgery) were identified in the same geographic region as the case facilities.

Results

Twenty-two percent of facilities responded to the survey. Fifty-four percent reported open access and 46% did not. There were no differences in facility or podiatry panel size, podiatry visits, or visit frequency between the cases and controls. Podiatry visits trended higher for control facilities but didn’t reach statistical significance. Case facilities had more new consults seen within 30 days (96%, 89%; P = 0.050) and lower minor amputation rates (0.62/1,000, 1.0/1,000; P = 0.041).

Conclusions

The VHA is the world’s largest managed care organization and it relies on clinical efficiencies as one mechanism to improve the quality of care. Open access clinics had more timely access for new patients and lower rates of minor amputations.

Keywords

Health care; Quality; Access; Evaluation; Delivery of health care; Amputation; Amputation prevention

Evidence for separatrix formation and sustainment with steady inductive helicity injection

The first sustainment of toroidal plasma current of 50 kA at up to 3 times the injected currents, added in quadrature, using steady inductive helicity injection is described. Separatrix currents-currents not linking the helicity injectors-are sustained up to 40 kA. Decreases in the n=1 toroidal mode of the poloidal magnetic field at higher current amplifications indicate more quiescent, direct toroidal current drive. Results are achieved in HIT-SI (with a spheromak of major radius 0.3 m) during deuterium operations immediately after helium operation. These results represent a breakthrough in the development of this new current drive method for magnetic confinement fusion.

The economic value of specialized lower-extremity medical care by podiatric physicians in the treatment of diabetic foot ulcers

BACKGROUND

We sought to examine the economic value of specialized lower-extremity medical care by podiatric physicians in the treatment of diabetic foot ulcers by evaluating cost outcomes for patients with diabetic foot ulcer who did and did not receive care from a podiatric physician in the year before the onset of a foot ulcer.

METHODS

We analyzed the economic value among commercially insured patients and Medicare-eligible patients with employer-sponsored supplemental medical benefits using the MarketScan Databases. The analysis consisted of two parts. In part I, we examined cost or savings per patient associated with care by podiatric physicians using propensity score matching and regression techniques; in part II, we extrapolated cost or savings to populations.

RESULTS

Matched and regression-adjusted results indicated that patients who visited a podiatric physician had $13,474 lower costs in commercial plans and $3,624 lower costs in Medicare plans during 2-year follow-up (P < .01 for both). A positive net present value of increasing the share of patients at risk for diabetic foot ulcer by 1% was found, with a range of $1.2 to $17.7 million for employer-sponsored plans and $1.0 to $12.7 million for Medicare plans.

CONCLUSIONS

These findings suggest that podiatric medical care can reduce the disease and economic burdens of diabetes.

Post-treatment leukocytosis predicts an unfavorable clinical response in patients with moderate to severe diabetic foot infections

Our aim was to determine whether post-treatment laboratory values could help to predict the clinical response in patients with advanced diabetic foot infections. One hundred and three consecutive patients hospitalized for moderate or severe diabetic foot infections at a large, university-affiliated hospital were identified and their records retrospectively reviewed. Definitive therapy during each patient's hospital course was defined as any foot surgery when additional major surgery was not anticipated or when a course of deep soft tissue and/or bone culture-specific antibiotics had been initiated. The clinical response was assessed at 90 days after the start of definitive therapy. A poor response was recognized as persistent infection at the initial or a contiguous site or when unplanned revision surgery or amputation was subsequently required. The peripheral white blood cell count, neutrophil count, erythrocyte sedimentation rate, and C-reactive protein levels measured shortly after initiating definitive therapy (i.e., post-treatment) were examined for their association with the clinical response using logistic regression models. A total of 38 patients with the complete compliment of laboratory and clinical follow-up aged 59.7 ± 12.3 years with a diabetes duration of 13.3 ± 9.1 years were included. Leukocytosis, defined as a white blood cell count >11,000 cells/μL, observed an average of 3 ± 1.4 days after treatment, was the single most important marker for predicting a poor clinical response, and the only significant study variable in both univariate and multivariate analyses (multivariate odds ratio 9.7, 95% confidence interval 1.0 to 92, p = .048). We conclude that leukocytosis observed shortly after initiating definitive therapy is predictive of an unfavorable clinical response by 90 days.

A proof-of-concept study for measuring gait speed, steadiness, and dynamic balance under various footwear conditions outside of the gait laboratory

BACKGROUND

This pilot study examined the effect of custom and prefabricated foot orthoses on self-selected walking speed, walking speed variability, and dynamic balance in the mediolateral direction.

METHODS

The gait of four healthy participants was analyzed with a body-worn sensor system across a distance of at least 30 m outside of the gait laboratory. Participants walked at their habitual speed in four conditions: barefoot, regular shoes, prefabricated foot orthoses, and custom foot orthoses.

RESULTS

In the custom foot orthoses condition, gait speed was improved on average 13.5% over the barefoot condition and 9.8% over the regular shoe condition. The mediolateral range of motion of center of mass was reduced 55% and 56% compared with the shoes alone and prefabricated foot orthoses conditions, respectively. This may suggest better gait efficiency and lower energy cost with custom foot orthoses. This tendency remained after normalizing center of mass by gait speed, suggesting that irrespective of gait speed, custom foot orthoses improve center of mass motion in the mediolateral direction compared with other footwear conditions. Gait intercycle variability, measured by intercycle coefficient of variation of gait speed, was decreased on average by 25% and 19% compared with the barefoot and shoes-alone conditions, respectively. The decrease in gait unsteadiness after wearing custom foot orthoses may suggest improved proprioception from the increased contact area of custom foot orthoses versus the barefoot condition.

CONCLUSIONS

These findings may open new avenues for objective assessment of the impact of prescribed footwear on dynamic balance and spatiotemporal parameters of gait and assess gait adaptation after use of custom foot orthoses.

Importance of time spent standing for those at risk of diabetic foot ulceration

OBJECTIVE

Despite the high cumulative plantar stress associated with standing, previous physical activity reports of diabetic patients at risk of foot ulceration have not taken this activity into account. This study aimed to monitor spontaneous daily physical activity in diabetic peripheral neuropathy (DPN) patients and examine both walking and standing activities as important foot-loading conditions.

RESEARCH DESIGN AND METHODS

Thirteen DPN patients were asked to wear a body-worn sensor for 48 h. Body postures (sitting, standing, and lying) and locomotion (walking, number of steps, and postural transition) were extracted.

RESULTS

Patients daily spent twice as much time standing (13±5%) as walking (6±3%). They spent 37±6% of time sitting and 44±8% lying down. The average number of steps per day was 7,754±4,087, and the number of walking episodes was 357±167 with maximum duration of 3.9±3.8 min.

CONCLUSIONS

The large portion of DPN patients' time spent standing with the feet loaded requires further consideration when treating and preventing foot ulcers.

Diabetic foot biomechanics and gait dysfunction

BACKGROUND

Diabetic foot complications represent significant morbidity and precede most of the lower extremity amputations performed. Peripheral neuropathy is a frequent complication of diabetes shown to affect gait. Glycosylation of soft tissues can also affect gait. The purpose of this review article is to highlight the changes in gait for persons with diabetes and highlight the effects of glycosylation on soft tissues at the foot-ground interface.

METHODS

PubMed, the Cochrane Library, and EBSCOhost on-line databases were searched for articles pertaining to diabetes and gait. Bibliographies from relevant manuscripts were also searched.

FINDINGS

Patients with diabetes frequently exhibit a conservative gait strategy where there is slower walking speed, wider base of gait, and prolonged double support time. Glycosylation affects are observed in the lower extremities. Initially, skin thickness decreases and skin hardness increases; tendons thicken; muscles atrophy and exhibit activation delays; bones become less dense; joints have limited mobility; and fat pads are less thick, demonstrate fibrotic atrophy, migrate distally, and may be stiffer.

INTERPRETATION

In conclusion, there do appear to be gait changes in patients with diabetes. These changes, coupled with local soft tissue changes from advanced glycosylated end products, also alter a patient's gait, putting them at risk of foot ulceration. Better elucidation of these changes throughout the entire spectrum of diabetes disease can help design better treatments and potentially reduce the unnecessarily high prevalence of foot ulcers and amputation.

Assessing postural control and postural control strategy in diabetes patients using innovative and wearable technology

INTRODUCTION

Currently, diagnosis of patients with postural instability relies on a rudimentary clinical examination. This article suggests an innovative, portable, and cost-effective prototype to evaluate balance control objectively.

METHODS

The proposed system uses low-cost, microelectromechanical sensor, body-worn sensors (BalanSens) to measure the motion of ankle and hip joints in three dimensions. We also integrated resulting data into a two-link biomechanical model of the human body for estimating the two-dimensional sway of the center of mass (COM) in anterior-posterior (AP) and medial-lateral (ML) directions. A new reciprocal compensatory index (RCI) was defined to quantify postural compensatory strategy (PCS) performance. To validate the accuracy of our algorithms in assessing balance, we investigated the two-dimensional sway of COM and RCI in 21 healthy subjects and 17 patients with diabetic peripheral neuropathic (DPN) complications using the system just explained. Two different conditions were examined: eyes open (EO) and eyes closed (EC) for duration of at least 30 seconds. Results were compared with center of pressure sway (COP) as measured by a pressure platform (Emed-x system, Novel Inc., Germany). To further investigate the contribution of the somatosensory (SOM) feedback to balance control, healthy subjects performed EO and EC trials while standing on both a rigid and a foam surface.

RESULTS

A relatively high correlation was observed between COM measured using BalanSens and COP measured using the pressure platform (r = 0.92). Results demonstrated that DPN patients exhibit significantly greater COM sway than healthy subjects for both EO and EC conditions (p < 0.005). The difference becomes highly pronounced while eyes are closed (197 +/- 44 cm(2) vs 68 +/- 56 cm(2)). Furthermore, results showed that PCS assessed using RCI is significantly better in healthy subjects compared to DPN subjects for both EO and EC conditions, as well as in both ML and AP directions (p < 0.05). Alteration in SOM feedback in healthy subjects resulted in diminished RCI values that were similar to those seen in DPN subjects (p > 0.05).

DISCUSSION/CONCLUSION

This study suggested an innovative system that enables the investigation of COM as well as postural control compensatory strategy in humans. Results suggest that neuropathy significantly impacts PCS.

Creating a diabetes foot reminder-based registry using the electronic medical record

OBJECTIVE

We created a new diabetes foot examination clinical reminder to directly populate a foot risk registry and examined its accuracy versus administrative data.

METHODS

A pre- and post-test design assessed accuracy of coding foot risk and clinician acceptability. The intervention hospital's reminder was replaced with a dialogue tick box containing the International Diabetic Foot Classification System to populate risk using health factors.

RESULTS

There were no hospital agreement differences for each foot condition except diabetes and peripheral neuropathy, demonstrating higher agreement at the intervention hospital. There were no differences in service agreement adherence or consulting rates although both demonstrated significantly lower consulting rates at study end. The intervention hospital had a significantly lower patient cancellation rate (1% v. 5%, P=0.01) and better coding for grade 3 patients. The new reminder demonstrated high acceptability.

CONCLUSIONS

The registry system resulted in improved discrimination of the highest foot risk. Further testing is recommended.

Gait changes with the use of Heelys: a case study

Heelys shoes are a novel athletic shoe with a concealed wheel. They have been popular among youths since their introduction in 2000. This case study serves as a first look into the biomechanical implications of Heelys shoes on gait. Pressure readings of the forefoot, midfoot, and rearfoot during ambulation in regular athletic-shoe walking, Heelys without the wheel walking, Heelys with the wheel walking, and Heelys skating with the wheel were recorded on a single subject using the Pedar X System. A visual gait analysis was also performed on the subject. The resulting data show increased forefoot and rearfoot pressure while walking with the Heelys with the wheel. The visual gait analysis showed a diminished heel strike and a more rapid forefoot loading. These results demonstrate that Heelys do in fact affect the biomechanics of gait.

Clinical factors associated with a conservative gait pattern in older male veterans with diabetes

Background

Patients with diabetes and peripheral neuropathy are at higher risk for falls. People with diabetes sometimes adopt a more conservative gait pattern with decreased walking speed, widened base, and increased double support time. The purpose of this study was to use a multivariate approach to describe this conservative gait pattern.

Methods

Male veterans (mean age = 67 years; SD = 9.8; range 37–86) with diabetes (n = 152) participated in this study from July 2000 to May 2001 at the Veterans Affairs Medical Center, White River Junction, VT. Various demographic, clinical, static mobility, and plantar pressure measures were collected. Conservative gait pattern was defined by visual gait analysis as failure to demonstrate a heel-to-toe gait during the propulsive phase of gait.

Results

Patients with the conservative gait pattern had lower walking speed and decreased stride length compared to normal gait. (0.68 m/s v. 0.91 m/s, p < 0.001; 1.04 m v. 1.24 m, p < 0.001) Age, monofilament insensitivity, and Romberg's sign were significantly higher; and ankle dorsiflexion was significantly lower in the conservative gait pattern group. In the multivariate analysis, walking speed, age, ankle dorsiflexion, and callus were retained in the final model describing 36% of the variance. With the inclusion of ankle dorsiflexion in the model, monofilament insensitivity was no longer an independent predictor.

Conclusion

Our multivariate investigation of conservative gait in diabetes patients suggests that walking speed, advanced age, limited ankle dorsiflexion, and callus describe this condition more so than clinical measures of neuropathy.

CLEAR Cleat: a proof-of-concept trial of an aerobic activity facilitator to reduce plantar forefoot pressures and their potential in those with foot ulcers

BACKGROUND

Exercise has not been studied extensively in persons with active neuropathic diabetic foot wounds, primarily because a device does not exist that allows patients to exercise while sufficiently off-loading pressure at the ulcer site. The purpose of this project was to demonstrate a device that reduces cycling plantar forefoot pressure.

METHODS

Ten healthy participants rode a recumbent bicycle under three cycling conditions. While the left foot interaction remained constant with a standard gym shoe and pedal, the right foot was exposed to a control condition with standard gym shoe and pedal, gym shoe and specialized cleat, and gym shoe with an off-loading insole and specialized cleat. Pressure and contact area of the plantar aspect of the feet were recorded for a 10-sec interval once during each minute of each condition's 7-min trial.

RESULTS

The off-loading insole and specialized cleat condition yielded significantly lower (P < .01) peak pressure, contact area, and pressure-time integral values in the forefoot than the specialized cleat condition with gym shoe, which yielded significantly lower values (P < .01) than the standard gym shoe and pedal.

CONCLUSION

Modifications to footwear may alter plantar forefoot pressures, contact area, and pressure-time integrals while cycling. The CLEAR Cleat could play a significant role in the facilitation of fitness in patients with (or at high risk for) neuropathic wounds.

Combined clinical and laboratory testing improves diagnostic accuracy for osteomyelitis in the diabetic foot

The purpose of this investigation was to examine the value of using routinely available clinical and laboratory tests in combination to distinguish osteomyelitis from cellulitis in a diabetic population with mild to moderately infected forefoot ulcers. We conducted a case-control study of 54 diabetic patients with 54 locally infected ulcers admitted to a university-affiliated tertiary-care hospital over a 4.5-year period. A total of 30 clinical and laboratory characteristics obtained at admission were tested for their association with pathology-proven osteomyelitis using logistic regression techniques. Ulcer depth greater than 3 mm (univariate odds ratio 10.4, P = .001) and C-reactive protein greater than 3.2 mg/dL (univariate odds ratio 10.8, P < .001) were the most informative individual clinical and laboratory tests for differentiating osteomyelitis from cellulitis. Adding C-reactive protein also significantly improved upon the accuracy of the study's best clinical testing strategy (area under the curve improved from 0.80 to 0.88, P = .040). Strategies that combined ulcer depth with serum inflammatory markers proved most useful in detecting ulcerated patients with concomitant bone infections (sensitivity 100% [95% CI 89.7%-100%] for both ulcer depth greater than 3 mm or C-reactive protein greater than 3.2 mg/dL, and ulcer depth greater than 3 mm or erythrocyte sedimentation rate greater than 60 mm/h). We conclude that considering clinical and laboratory findings together can significantly improve our diagnostic accuracy for osteomyelitis in the diabetic foot. The specific combination of ulcer depth with serum inflammatory markers appears to be a particularly sensitive strategy that may allow for greater detection of early diabetic osteomyelitis.

LEVEL OF CLINICAL EVIDENCE

3.

Reliability and validity of current physical examination techniques of the foot and ankle

BACKGROUND

This literature review was undertaken to evaluate the reliability and validity of the orthopedic, neurologic, and vascular examination of the foot and ankle.

METHODS

We searched PubMed-the US National Library of Medicine's database of biomedical citations-and abstracts for relevant publications from 1966 to 2006. We also searched the bibliographies of the retrieved articles. We identified 35 articles to review. For discussion purposes, we used reliability interpretation guidelines proposed by others. For the kappa statistic that calculates reliability for dichotomous (eg, yes or no) measures, reliability was defined as moderate (0.4-0.6), substantial (0.6-0.8), and outstanding (> 0.8). For the intraclass correlation coefficient that calculates reliability for continuous (eg, degrees of motion) measures, reliability was defined as good (> 0.75), moderate (0.5-0.75), and poor (< 0.5).

RESULTS

Intraclass correlations, based on the various examinations performed, varied widely. The range was from 0.08 to 0.98, depending on the examination performed. Concurrent and predictive validity ranged from poor to good.

CONCLUSIONS

Although hundreds of articles exist describing various methods of lower-extremity assessment, few rigorously assess the measurement properties. This information can be used both by the discerning clinician in the art of clinical examination and by the scientist in the measurement properties of reproducibility and validity.

Use of chlorhexidine-impregnated patch at pin site to reduce local morbidity: the ChIPPS Pilot Trial

Pin tract infection is one of the most common complications associated with the use of external fixation. While some studies have identified the potential benefit of chlorhexidine gluconate-impregnated polyurethane dressings to reduce the incidence of catheter-related bloodstream infections, we are unaware of any published studies that evaluate the effectiveness of similar technologies in reducing the risk for external-fixation-related pin tract infections. Therefore, the purpose of this study was to evaluate the effectiveness of chlorhexidine gluconate-impregnated polyurethane dressing in reducing percutaneous-device-related skin colonisation and local infections. In this initial retrospective cohort, data were abstracted for two groups of consecutive patients undergoing surgery involving external fixation at an interdisciplinary foot and ankle surgical unit. All patients received surgical treatment of their foot/ankle pathology along with application of a hybrid external fixator. Twenty patients (45% male, age 54.5 +/- 3.69 years) received chlorhexidine gluconate-impregnated polyurethane dressing and twenty (55% male, age 55.8 +/- 3.22 years) received standard pin care. There was a significantly higher rate of pin tract infection in patients who received standard pin care compared with those who received chlorhexidine gluconate-impregnated polyurethane dressings (25% versus 0%, P = 0.047). There was no significant difference in any of the descriptive study characteristics (age, gender, diabetes and presence of neuropathy). The results of this initial study suggest that chlorhexidine gluconate-impregnated polyurethane dressing may be effective to reduce the incidence of pin tract infections and help decrease morbidity associated with external fixation.