In people with diabetes mellitus, the Charcot foot is a specific manifestation of peripheral neuropathy that may involve autonomic neuropathy with high blood flow to the foot, leading to increased bone resorption. It may also involve peripheral somatic polyneuropathy with loss of protective sensation and high risk of unrecognized acute or chronic minor trauma. In both cases, there is excess local inflammatory response to foot injury, resulting in local osteoporosis. In the Charcot foot, the acute and chronic phases have been described. The former is characterized by local erythema, edema, and marked temperature elevation, while pain is not a prominent symptom. In the latter, signs of inflammation gradually recede and deformities may develop, increasing the risk of foot ulceration. The most common anatomical classification describes five patterns, according to the localization of bone and joint pathology. This review article aims to provide a brief overview of the diabetic Charcot foot in terms of etiology, pathophysiology, and classification.
Charcot foot; classification; diabetes mellitus; diabetic foot; neuropathy; osteoarthropathy
The diagnosis of Sudeck's syndrome stage 1 (nowadays termed complex regional pain syndrome I, abbreviated CRPS I) is based on clinical features, namely swelling and pain in a limb. Plain X-ray may be normal. In the absence of pain sensitivity, e.g. in diabetic neuropathy, CRPS I of the foot can be mistaken for Charcot's foot stage 0 (so-called neuro-osteoarthropathy).
The case of a type-1 diabetic woman is reported, in whom CRPS I following a calcaneal fracture was mistaken for Charcot's osteoarthropathy (because of bone marrow edema displayed by conventional MR imaging). In addition, a review is presented on 6 consecutive cases with CRPS I of the foot, and on 20 cases with Charcot's foot stage 0, with particular emphasis on MR imaging findings. The number of bones per foot affected with marrow edema was similar in either condition, with a tendency towards a more patchy, diffuse distribution of bone marrow edema in CRPS I. Bone marrow edema apparently regressed more promptly in response to treatment in Charcot's foot stage 0.
Differentiation of CRPS I from Charcot's foot stage 0 remains a diagnostic dilemma in patients with pain insensitivity. Conventional MRI may be helpful, when repeated for monitoring the treatment response.
To review the clinical outcome of arthrodesis of the foot in patients with diabetic Charcot arthropathy and to review the pathophysiology, clinical and radiographic features of Charcot arthropathy.
A retrospective review and clinical follow-up of a series of patients.
St. Michael’s Hospital, Toronto, a tertiary care teaching hospital.
Ten diabetic patients treated between 1996 and 1998 who required an arthrodesis of the midfoot or hindfoot secondary to deformity of diabetic neuropathic joints.
Three midfoot (Lisfranc) and 7 hindfoot arthrodeses with autogenous iliac-crest bone grafting and internal fixation.
Patient satisfaction, maintenance of the correction of the deformity and avoidance of amputation. Western Ontario/McMaster University score and midfoot/hindfoot American Orthopaedic Foot and Ankle Society foot ratios. Clinical examination including E-MED pedographic examination. Correction and evidence of bony or fibrous union assessed radiologically.
The postoperative correction was maintained, no further skin ulceration occurred and amputation was avoided in 9 of 10 patients. Because this is a salvage procedure and there was often significant concomitant illness, the results of clinical rating systems were poor. Five of 9 patients had clinical and radiographic evidence of a solid bony arthrodesis; 4 had a stable fibrous union.
With careful surgical technique, a reasonable number of feet can be salvaged by an arthrodesis of a diabetic neuropathic joint when nonoperative measures fail. Patient selection is important because there is a significant complication rate.
Both osteomyelitis and Charcot neuro-osteoarthropathy (CN) are potentially limb-threatening complications of diabetic neuropathy, but they require quite different treatments. Almost all bone infections in the diabetic foot originate from an infected foot ulcer while diabetic osteoarthropathy is a non-infectious process in which peripheral neuropathy plays the critical role. Differentiating between diabetic foot osteomyelitis and CN requires careful evaluation of the patient, including the medical history, physical examination, selected laboratory findings, and imaging studies. Based on available studies, we review the approaches to the diagnostic differentiation of osteomyelitis from CN of the foot in diabetic patients.
diabetic foot; osteomyelitis; Charcot neuro-osteoarthropathy
Charcot arthropathy of the foot is a rare but devastating complication of diabetes that remains to be a challenging issue for the foot and ankle surgeons. Charcot foot fails to be an obvious diagnostic option that comes to mind, even in a pathognomonic clinical appearance. The rarity of the disorder, more common pathologies that mimic the condition, and the self-limiting prognosis deviate the clinician from the right diagnosis. The clinical challenges in the diagnosis of Charcot foot require in-depth investigations of its enigmatic nature to establish useful guidelines. Yet, this goal seems to be beyond reach, without a holistic view of the immense literature concerning the pathophysiology of the disorder. The primary objective of this article is to put together and review the recent advancements about the etiology and intrinsic mechanisms of diabetic Charcot foot.
Charcot foot; pathophysiology; diabetes mellitus; neuropathy; neuropeptides
The etiology of diabetic Charcot neuroarthropathy involving the midfoot often includes an inciting traumatic event or repetitive micro-trauma from an uncompensated biomechanical imbalance that potentiates an incompletely understood pathway leading to a rocker-bottom foot deformity and ulceration. In the setting of a severe Charcot foot fracture and/or dislocation with obvious osseous instability, diagnostic delay can potentiate the limb-threatening sequelae of infected midfoot ulcerations in this patient population. In this article, the authors discuss the thought process as well as the advantages of performing an extended medial column arthrodesis for selected Charcot midfoot deformities.
diabetes mellitus; Charcot foot; midfoot arthrodesis; locking plate technology; external fixation
To measure prospectively bone mineral density (BMD) of the Charcot and non-Charcot foot in 36 diabetic patients presenting with acute Charcot osteoarthropathy.
RESEARCH DESIGN AND METHODS
Calcaneal BMD was measured with quantitative ultrasound at presentation, at 3 months of casting, and at the time of the clinical resolution.
BMD of the Charcot foot was significantly reduced compared with BMD of the non-Charcot foot at presentation (P = 0.001), at 3 months of casting (P < 0.001), and at the time of clinical resolution (P < 0.001). Overall, from the time of presentation to the time of resolution there was a significant fall of BMD of the Charcot foot (P < 0.001) but not of the non-Charcot foot (P = 0.439).
Although the Charcot foot was treated with casting until clinical resolution, there was a significant fall of BMD only from presentation up until 3 months of casting.
Diabetic foot diseases, such as ulcerations, infections, and neuropathic (Charcot’s) arthropathy are major complications of diabetes mellitus and peripheral neuropathy and may cause osteolysis (bone loss) in foot bones. The purposes of our study were to make computed tomography (CT) measurements of foot-bone volumes and densities and to determine measurement precision (percent coefficients of variation for root mean square-standard deviations) and least significant changes in these percentages that could be considered biologically real with 95% confidence. Volumetric quantitative CT scans were performed and repeated on 10 young, healthy subjects and 13 subjects with diabetes mellitus and peripheral neuropathy. Two raters used the original- and repeat-scan data sets to make measurements of volumes and bone mineral densities (BMDs) of the tarsal and metatarsal bones of the two feet (24 bones). Precisions for the bones ranged from 0.1% to 0.9% for volume measurements and from 0.6% to 1.9% for BMD measurements. The least significant changes ranged from 0.4% to 2.5% for volume measurements and from 1.5% to 5.4% for BMD measurements. Volumetric quantitative CT provides precise measurements of volume and BMD for metatarsal bones and tarsal bones where diabetic foot diseases commonly occur.
Precision; Whole Bone Volume; Bone Mineral Density; Foot; Diabetes Mellitus; Peripheral Neuropathy
The management of diabetic neuropathic foot and ankle malunions and/or nonunions is often complicated by the presence of broken or loosened hardware, Charcot joints, infection, osteomyelitis, avascular bone necrosis, unstable deformities, bone loss, disuse and pathologic osteopenia, and ulcerations. The author discusses a rational approach to functional limb salvage with various surgical techniques that are aimed at achieving anatomic alignment, long-term osseous stability, and adequate soft tissue coverage. Emphasis is placed on techniques to overcome the inherent challenges that are encountered when surgically managing a diabetic nonunion and/or malunion. Particular attention is directed to the management of deep infection and Charcot neuroarthropathy in the majority of the cases presented.
charcot foot; external fixation; malunions; nonunions; diabetic foot
Charcot neuroarthropathy (CN) is a severe joint disease in the foot and ankle that can result in fracture, permanent deformity, and limb loss. It is a serious and potentially limb-threatening lower-extremity late complication of diabetes mellitus. The aim of this manuscript was to evaluate modern concepts of chronic CN through a review of the available literature and to integrate a perspective of management from the authors’ extensive experience.
Charcot foot; diabetes mellitus; total contact cast; arthrodesis; diabetic neuropathy
There is limited understanding of the foot-health of people with diabetes in Australian regional areas. The aim of this study was to document the foot-health of people with diabetes who attend publically funded podiatric services in a regional Australian population.
A three month prospective clinical audit was undertaken by the publically-funded podiatric services of a large regional area of Victoria, Australia. The primary variables of interest were the University of Texas (UT) diabetic foot risk classification of each patient and the incidence of new foot ulceration during the study period. Age, gender, diabetes type, duration of diabetes and the podiatric service the patients attended were the other variables of interest.
Five hundred and seventy six patients were seen during the three month period. Over 49% had a UT risk classification at a level at least peripheral neuropathy or more serious diabetes-related foot morbidity. Higher risk at baseline was associated with longer duration of diabetes (F = 31.7, p < 0.001), male gender (χ2 = 40.3, p <0.001) and type 1 diabetes (χ2 = 37.3, p <0.001). A prior history of foot pathology was the overwhelming predictor for incident ulceration during the time period (OR 8.1 (95% CI 3.6 to 18.2), p < 0.001).
The publically funded podiatric services of this large regional area of Australia deal with a disproportionally large number of people with diabetes at high risk of future diabetes-related foot complications. These findings may be useful in ensuring appropriate allocation of resources for future public health services involved in diabetic foot health service delivery in regional areas.
Podiatry; Diabetic Foot; Epidemiology; Rural Health
We describe two patients with diabetes mellitus and associated neuropathy, who presented with painless foot swelling and no history of trauma. X-Rays revealed recent underlying fractures-in one of a metatarsus, and the other of a proximal phalanx. These were assumed to be 'stress' fractures unassociated with pain because of the severe sensory neuropathy. Though spontaneous fractures in neuropathic feet have been previously described, they almost always occur in association with Charcot joints, and are usually painful. The differential diagnosis of acute swelling in the foot of a diabetic patient with sensory neuropathy should include stress fracture.
Athletic trainers must understand the clinical implications of diabetes on the athletic foot in order to promote proper foot care and footwear and to adapt protocols for treatment and exercise of the affected athlete.
The MEDLINE and CINAHL databases were searched for the years 1984 to 1996 with the terms “diabetes and foot,” “neuropathy,” and “Charcot joint.”
As more athletes with diabetes participate in sports, athletic trainers must develop the skills and knowledge necessary to manage this metabolic illness. Although the need to keep blood glucose levels carefully controlled is well known, the impact of diabetes on the foot is not as well recognized. Peripheral vascular disease, soft tissue neuropathy, and neuropathic arthropathy are the most common complications of diabetes affecting the foot. However, with proper management, these complications can be minimized, allowing diabetic athletes and nonathletes to lead more normal and functional lives.
The athletic trainer can assist the diabetic athlete by promoting proper foot care and footwear and adapting protocols for treatment and exercise.
peripheral vascular disease; neuropathy; neuropathic arthropathy
To compare risks of lower-extremity amputation between patients with Charcot arthropathy and those with diabetic foot ulcers.
RESEARCH DESIGN AND METHODS
A retrospective cohort of patients with incident Charcot arthropathy or diabetic foot ulcers in 2003 was followed for 5 years for any major and minor amputations in the lower extremities.
After a mean follow-up of 37 ± 20 and 43 ± 18 months, the Charcot and ulcer groups had 4.1 and 4.7 amputations per 100 person-years, respectively. Among patients <65 years old at the end of follow-up, amputation risk relative to patients with Charcot alone was 7 times higher for patients with ulcer alone and 12 times higher for patients with Charcot and ulcer.
Charcot arthropathy by itself does not pose a serious amputation risk, but ulcer complication multiplicatively increases the risk. Early surgical intervention for Charcot patients in the absence of deformity or ulceration may not be advisable.
Charcot neuroarthropathy (CN) is a serious complication of diabetes mellitus that can cause major morbidity including limb amputation. Since it was first described in 1883, and attributed to diabetes mellitus in 1936, the diagnosis of CN has been very challenging even for the experienced practitioners. Imaging plays a central role in the early and accurate diagnosis of CN, and in distinction of CN from osteomyelitis. Conventional radiography, computed tomography, nuclear medicine scintigraphy, magnetic resonance imaging, and positron emission tomography are the imaging techniques currently in use for the evaluation of CN but modalities other than magnetic resonance imaging appeared to be complementary. This study focuses on imaging findings of acute and chronic neuropathic osteoarthropathy in diabetes and discrimination of infected vs. non-infected neuropathic osteoarthropathy.
diabetes mellitus; complications; diabetic foot; Charcot foot; diagnostic imaging
Reduced traumatic and posttraumatic (nociceptive) pain is a key feature of diabetic neuropathy. Underlying condition is a gradual degeneration of endings of pain nerves (A-delta fibers and C-fibers), which operate as receivers of noxious stimuli (nociceptors). Hence, the absence of A-delta fiber mediated sharp pain (“first” pain), and of C-fiber mediated dull pain (“second” pain). However, patients with diabetic neuropathy and acute Charcot foot often experience deep dull aching in the Charcot foot while walking on it.
To create a unifying hypothesis on the kind of pain in an acute Charcot foot.
Absence of punctuate (pinprick) pain perception at the sole of a Charcot foot, as was shown recently, likely corresponds to vanished intraepidermal A-delta fiber endings. C-fiber nociceptors are reduced, according to histopathology studies. Both types of fibers contribute to posttraumatic hyperalgesia at the skin level, as studies show. Their deficiencies likely impact on posttraumatic hyperalgesia at the skin level and, probably, also at the skeletal level.
It is hypothesised that deep dull aching in an acute diabetic Charcot foot may represent faulty posttraumatic hyperalgesia involving cutaneous and skeletal tissues.
pain perception; diabetic neuropathy; Charcot neuroarthropathy
To identify the differences in a socioeconomic profile between two cohorts of diabetic patients – one with diabetic foot problems and another without diabetic foot problems.
Materials and methods
The cohort with diabetic foot problems (including cellulitis, abscess, osteomyelitis, septic arthritis, gangrene, ulcers, or Charcot joint disease) consisted of 122 diabetic patients, while the other cohort without foot problems consisted of 112 diabetic patients. Both were seen at the National University Hospital from January to April 2007. A detailed protocol was designed and the factors studied included patient profile, average monthly household income, education, compliance to diabetic medication, attendance at clinics for diabetic treatment, exercise, smoking, alcohol consumption, gender, and glycosylated haemoglobin (HbA1C) level. These were studied for significant differences using univariate and stepwise multivariate logistic regression analysis.
With multivariate analysis, Malay ethnicity (p<0.001), education of up to secondary school only (p=0.021), low average monthly household income of less than SGD $2,000 (p=0.030), lack of exercise (at least once a week, p=0.04), and elevated HbA1C level (>7.0%; p=0.015) were found to be significantly higher in the cohort with diabetic foot problems than the cohort without.
There are significant differences in the socioeconomic factors between diabetic patients with diabetic foot problems and those without.
diabetic foot; social conditions; patient compliance; income; HbA1c
Charcot's neuroarthropathy of ankle leads to instability, destruction of the joint with significant morbidity that may require an amputation. Aim of surgical treatment is to achieve painless stable plantigrade foot through arthrodesis. Achieving surgical arthrodesis in Charcot's neuroarthropathy has a high failure rate. This is a retrospective nonrandomized comparative study assessing the outcomes of tibio-talar arthrodesis for Charcot's neuroarthropathy treated by uniplanar external fixation assisted by external immobilization or retrograde intramedullary interlocked nailing.
Materials and Methods:
Records of the authors′ institution were reviewed to identify those patients who had undergone ankle fusion for diabetic neuroarthropathy from January 1998 to December 2008. A total of11 patients (six males and five females) with a mean age of 56 year and diabetes of a mean duration of 15.4 years with ankle tibio-talar arthrodesis using retrograde nailing or external fixator for Charcot's neuroarthropathy were enrolled for the analysis. Neuropathy was clinically diagnosed, documented and substantiated using the monofilament test. All procedures were performed in Eichenholz stage II/III.Six patients were treated with uniplanar external fixator, while the remaining five underwent retrograde intramedullary interlocking nail. The outcomes were measured for union radiologically, development of complications and clinical follow-up, according to digital archiving systems and old case notes.
All five (100%) patients treated by intramedullary nailing achieved radiological union on an average follow-up of 16 weeks. The external fixation group had significantly higher rate of complications with one amputation, four non unions (66.7%) and a delayed union which went on to full osseous union.
The retrograde intramedullary nailing for tibio-talar arthrodesis in Charcot's neuroarthropathy yielded significantly better outcomes as compared to the use of uniplanar external fixator.
Charcot's diabetic neuropathy; retrograde intramedullary nailing; tibio-talar arthrodesis; uniplanar external fixator
Charcot osteoarthropathy (COA) is a potentially limbthreatening condition that mainly affects diabetic patients with neuropathy. In everyday practice, it presents as a red, hot, swollen foot, usually painless, and is frequently triggered by trivial injury. Its etiology is traditionally attributed to impairment of either the autonomic nervous system, leading to increased blood flow and bone resorption, or of the peripheral nervous system, whereby loss of pain and protective sensation render the foot susceptible to repeated injury. More recently, excessive local inflammation is thought to play a decisive role. Diagnosis is based on clinical manifestation and imaging studies (plain X-rays, bone scan, Magnetic Resonance Imaging). The mainstay of management is immediate off-loading, while surgery is usually reserved for chronic cases with irreversible deformities and/or joint instability. The aim of this review is to provide an overview of COA in terms of pathogenesis, classification and clinical presentation, diagnosis and treatment, with an emphasis on the high suspicion required by clinicians for timely recognition to avoid further complications.
Charcot osteoarthropathy; Diabetes mellitus; Diabetic neuropathy; Diabetic foot
The Lisfranc injury is relatively uncommon yet remains popular in the literature due to its variable causative mechanisms and subtleties in radiographic features despite its potential for disabling long term outcomes if treatment is inadequate, inappropriate or delayed. These injuries are especially pertinent in diabetic patients, especially those with neuropathy, since they are more common, can lead to Charcot neuropathic joint, ulcers and have different causative mechanisms compared to the general population. We describe the case of a neuropathic diabetic patient who presented with a Lisfranc injury which precipitated the development of acute Charcot arthropathy in the right foot. The case serves to illustrate several salient points about the Lisfranc joint and related injuries in diabetic patients.
Neuropathic deformities impair foot and ankle joint mobility, often leading to abnormal stresses and impact forces. The purpose of our study was to determine differences in radiographic measures of hind foot alignment and ankle joint and subtalar joint motion in participants with and without neuropathic midfoot deformities and to determine the relationships between radiographic measures of hind foot alignment to ankle and subtalar joint motion in participants with and without neuropathic midfoot deformities.
Sixty participants were studied in three groups. Forty participants had diabetes mellitus (DM) and peripheral neuropathy (PN) with 20 participants having neuropathic midfoot deformity due to Charcot neuroarthropathy (CN), while 20 participants did not have deformity. Participants with diabetes and neuropathy with and without deformity were compared to 20 young control participants without DM, PN or deformity. Talar declination and calcaneal inclination angles were assessed on lateral view weight bearing radiograph. Ankle dorsiflexion, plantar flexion and subtalar inversion and eversion were assessed by goniometry.
Talar declination angle averaged 34±9, 26±4 and 23±3 degrees in participants with deformity, without deformity and young control participants, respectively (p< 0.010). Calcaneal inclination angle averaged 11±10, 18±9 and 21±4 degrees, respectively (p< 0.010). Ankle plantar flexion motion averaged 23±11, 38±10 and 47±7 degrees (p<0.010). The association between talar declination and calcaneal inclination angles with ankle plantar flexion range of motion is strongest in participants with neuropathic midfoot deformity. Participants with talonavicular and calcaneocuboid dislocations result in the most severe restrictions in ankle joint plantar flexion and subtalar joint inversion motions.
An increasing talar declination angle and decreasing calcaneal inclination angle is associated with decreases in ankle joint plantar flexion motion in individuals with neuropathic midfoot deformity due to CN that may contribute to excessive stresses and ultimately plantar ulceration of the midfoot.
Foot alignment; Deformity; Ankle and foot joint goniometry; Limited joint mobility
Foot problems in patients with diabetes remain a major public health issue and are the commonest reason for hospitalization of patients with diabetes with prevalence as high as 25%. Ulcers are breaks in the dermal barrier with subsequent erosion of underlying subcutaneous tissue that may extend to muscle and bone, and superimposed infection is a frequent and costly complication. The pathophysiology of diabetic foot disease is multifactorial and includes neuropathy, infection, ischemia, and abnormal foot structure and biomechanics. Early recognition of the etiology of these foot lesions is essential for good functional outcome. Managing the diabetic foot is a complex clinical problem requiring a multidisciplinary collaboration of health care workers to achieve limb salvage. Adequate off-loading, frequent debridement, moist wound care, treatment of infection, and revascularization of ischemic limbs are the mainstays of therapy. Even when properly managed, some of the foot ulcers do not heal and are arrested in a state of chronic inflammation. These wounds can frequently benefit from various adjuvants, such as aggressive debridement, growth factors, bioactive skin equivalents, and negative pressure wound therapy. While these, increasingly expensive, therapies have shown promising results in clinical trials, the results have yet to be translated into widespread clinical practice leaving a huge scope for further research in this field.
The Charcot knee - or neuropathic arthropathy - presents a considerable challenge to the orthopaedic surgeon. Caused by a combination of sensory, motor and autonomic neuropathy, it was originally described as an arthritic sequelae of neurosyphilis. In today's western orthopaedics it is more often caused by diabetes. A Charcot knee is often symptomatically painful and unstable. Traditional management has usually been conservative or arthrodesis, with limited success. Arthroplasty of a Charcot joint has commonly been avoided at all costs. However, in the right patient, using the right technique, arthroplasty can significantly improve the symptoms of a Charcot joint. This article explores the evidence surrounding the role of arthroplasty in the management of a Charcot knee. Arthroplasty is compared to other forms of treatment and specific patient demographics and surgical techniques are explored in an attempt to define the role of arthroplasty in the management of a Charcot knee.
Charcot joint; knee; arthroplasty; neuropathic arthropathy.
We present the case of a 33-year-old male who sustained a burst fracture D12 vertebrae with spinal cord injury (ASIA impairment scale A) and a right mid-diaphysial femoral shaft fracture around 1.5 years back. The patient reported 1.5 years later with a swelling over the right buttock. Arthrotomy revealed serous fluid and fragmented bone debris. The biopsy showed a normal bony architecture with no evidence of infection and malignant cells. Hence, a diagnosis of Charcot’s hip was made. Charcot’s neuroarthropathy of the feet is a well-recognized entity in the setting of insensate feet resulting from causes such as diabetes or spina bifida. Although Charcot’s disease of the hips has been described, it is uncommon in association with spinal cord injury, syphilis and even with the use of epidural injection. The present case highlights the fact that neuroarthropathy of the hip can occur in isolation in the setting of a spinal cord injury, and this can lead to considerable morbidity.
Charcot’s hip; neuroarthropathy; spinal cord injury
Objective. Asymmetric plantar temperature differences secondary to inflammation is a hallmark for the diagnosis and treatment response of Charcot foot syndrome. However, little attention has been given to temperature response to activity. We examined dynamic changes in plantar temperature (PT) as a function of graduated walking activity to quantify thermal responses during the first 200 steps.
Methods. Fifteen individuals with Acute Charcot neuroarthropathy (CN) and 17 non-CN participants with type 2 diabetes and peripheral neuropathy were recruited. All participants walked for two predefined paths of 50 and 150 steps. A thermal image was acquired at baseline after acclimatization and immediately after each walking trial. The PT response as a function of number of steps was examined using a validated wearable sensor technology. The hot spot temperature was identified by the 95th percentile of measured temperature at each anatomical region (hind/mid/forefoot). Results. During initial activity, the PT was reduced in all participants, but the temperature drop for the nonaffected foot was 1.9 times greater than the affected side in CN group (P = 0.04). Interestingly, the PT in CN was sharply increased after 50 steps for both feet, while no difference was observed in non-CN between 50 and 200 steps. Conclusions. The variability in thermal response to the graduated walking activity between Charcot and non-Charcot feet warrants future investigation to provide further insight into the correlation between thermal response and ulcer/Charcot development. This stress test may be helpful to differentiate CN and its response to treatment earlier in its course.