Charcot neuro-osteoarthropathy-current standards

Rare complication of rheumatoid arthritis: Charcot Neuro-osteoarthropathy

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease.However, there are few cases of Charcot Neuro-osteoarthropathy (CN) caused by rheumatoid diseases in clinical reports. It is not easy to pay attention to the diagnosis of CN in the complications of rheumatoid disease, which greatly increases the probability of misdiagnosis and missed diagnosis. This case reported a rare complication of rheumatoid arthritis, Charcot arthritis, and the molecular mechanism and diagnosis and treatment of CN caused by RA were systematically discussed.

CASE PRESENTATION

The patient, a 79-year-old woman, was hospitalized due to bilateral shoulder pain, limited activity for half a year, aggravated for 4 months to the hospital. During this period, the symptoms did not improve after treatment with acupuncture and Chinese medicine. The patient was previously diagnosed with rheumatoid arthritis for more than 3 years and intermittent irregular use of methylprednisolone and methotrexate for 2 years. She had a history of osteoporosis.

PHYSICAL EXAMINATION

symmetrical malformed swelling of the finger joints of both hands; Bilateral supraspinatus and deltoid muscle atrophy, tenderness at the acromion, and attachment of the long head tendon of the biceps brachii were observed. The left Dugas test and the right Dugas test were positive.Blood test: anti-cyclic citrullinated peptide antibody (A-CCP) 33.10U/ml (normal range: 0-5RU/ml); antinuclear antibody quantification (ANA) 47.40AU/ml (normal range: Negative or < 32); anti-double stranded DNA IgG antibody quantification (dsDNA) 31.00 IU/ml (normal range: 0-100 IU/ml); D-Dimer 6.43 µg/ml (normal range: 0-0.5 mg/L); erythrocyte sedimentation rate (ESR) was 27 mm/h (normal range: < 20 mm/60 min). C-reactive protein (CRP) 39.06 mg/L(0.068-8 mg/L).MRI 3.0 T enhancement of bilateral shoulder joints, cervical spine and thoracic spine showed: 1.Large bone destruction, cartilage injury, multiple effusion, synovitis, obvious on the right side. 2.Intervertebral disc degeneration, cervical 3/4, 4/5, 5/6, 6/7 disc herniation, with cervical 3/4 obvious, posterior central herniation; CONCLUSIONS: Rheumatoid arthritis complicated with Charcot's joint is rare. Clinically, patients with rheumatoid diseases should not ignore Charcot's joint complications because of rareness. Early blood inflammatory markers, neuro electrophysiology, and imaging MRI of rheumatoid CN are of great significance for the diagnosis of this mild or early neurovascular inflammation. Early diagnosis and treatment are helpful to prevent further joint injury. The clinical diagnosis, treatment, and molecular mechanism of osteolysis in RA and peripheral sensory nerve injury remain to be further revealed.

Contralateral foot temperature monitoring during Charcot immobilisation: A systematic review

AIMS

Contralateral temperature difference (CTD) is a frequently used marker of healing in Charcot neuro-osteoarthropathy (CN). We aimed to determine whether there is a consistent approach to CTD measurement during healing and the decision-making process around cessation of immobilisation.

MATERIALS AND METHODS

Medline, Scopus, and Web of Science were searched until February 2022 for peer-reviewed studies using keywords, including (('arthropathy' OR 'osteoarthropathy' OR 'osteopathy' OR 'neuroarthropathy') AND 'Charcot' AND ('temperature')), which returned 789 results excluding duplicates. Included studies monitored CTD in those with active CN to (i) assess the healing process and (ii) assist in determining the transition from immobilisation.

RESULTS

Thirty four studies in total (n = 677 participants) were shortlisted and 19 were included after full paper review. Average CTD at presentation varied from 1.6 to 8.0°C with insufficient data to determine if CTD was proportional to severity of Charcot. Evidence of a relationship between CTD and radiographic or scintigraphy-based markers of healing varied depending on the methodology employed. Threshold CTD for the cessation of immobilisation ranged from <1°C to <2°C. Most frequently it was <2°C sustained for 2-3 visits. Temperature was monitored typically every 2-6 weeks using handheld thermometry at CN site(s) after resting the feet for 15 min. Device type, accuracy/reliability, and ambient temperature were rarely reported.

CONCLUSIONS

Further research on CTD and radiographic and radiotracer markers is needed involving larger cohorts. Standardisation in reporting of thermometry device type, accuracy and reliability, foot resting times, and ambient temperature controls is essential to facilitate the comparison of studies, meta-analysis, and evaluation of different immobilisation interventions.

Long-term follow-up of conservative treatment of Charcot feet

BACKGROUND

Charcot arthropathy (CN) can ultimately lead to limb loss despite appropriate treatment. Initial conservative treatment is the accepted treatment in case of a plantigrade foot. The aim of this retrospective study was to investigate the mid- to long-term clinical course of CN initially being treated conservatively, and to identify risk factors for reactivation and contralateral development of CN as well as common complications in CN.

METHODS

A total of 184 Charcot feet in 159 patients (median age 60.0 (interquartile range (IQR) 15.5) years, 49 (30.1%) women) were retrospectively analyzed by patient chart review. Rates of limb salvage, reactivation, contralateral development and common complications were recorded. Statistical analysis was performed to identify possible risk factors for limb loss, CN reactivation, contralateral CN development, and ulcer development.

RESULTS

Major amputation-free survival could be achieved in 92.9% feet after a median follow-up of 5.2 (IQR 4.25, range 2.2-11.25) years. CN recurrence occurred in 13.6%. 32.1% had bilateral CN involvement. Ulcers were present in 72.3%. 88.1% patients were ambulating in orthopaedic footwear without any further aids. Presence of Diabetes mellitus was associated with reactivation of CN, major amputation and ulcer recurrence. Smoking was associated with ulcer development and necessity of amputations.

CONCLUSIONS

With consistent conservative treatment of CN with orthopaedic footwear or orthoses, limb preservation can be achieved in 92.9% after a median follow-up of 5.2 years. Patients with diabetic CN are at an increased risk of developing complications and CN reactivation. To prevent ulcers and amputations, every effort should be made to make patients stop smoking.

LEVEL OF EVIDENCE

III, long-term retrospective cohort study.

Effect of Recombinant Human Parathyroid Hormone (1-84) on Resolution of Active Charcot Neuro-osteoarthropathy in Diabetes: A Randomized, Double-Blind, Placebo-Controlled Study

OBJECTIVE

Fractures in Charcot neuro-osteoarthropathy (CN) often fail to heal despite prolonged immobilization with below-knee casting. The aim of the study was to assess the efficacy of recombinant human parathyroid hormone (PTH) in reducing time to resolution of CN and healing of fractures.

RESEARCH DESIGN AND METHODS

People with diabetes and acute (active) Charcot foot were randomized (double-blind) to either full-length PTH (1-84) or placebo therapy, both in addition to below-knee casting and calcium and vitamin D3 supplementation. The primary outcome was resolution of CN, defined as a skin foot temperature difference >2°C at two consecutive monthly visits.

RESULTS

Median time to resolution was 5 months (95% CI 4, 12) in intervention and 6 months (95% CI 2, 9) in control. On univariate mixed Cox and logistic regression, there was no significant difference in time to resolution between the groups (P = 0.64) or in the likelihood of resolution (P = 0.66). The hazard ratio of resolution was 0.84 (95% CI 0.41, 1.74; P = 0.64), and the odds ratio of resolution by 12 months was 0.80 (95% CI 0.3, 2.13; P = 0.66) (intervention vs. control). On linear regression analysis, there were no significant differences in the effect of treatment on fracture scores quantitated on MRI scans (coefficient 0.13 [95% CI -0.62, 0.88]; P = 0.73) and on foot and ankle X-rays (coefficient 0.30 [95% CI -0.03, 0.63]; P = 0.07).

CONCLUSIONS

This double-blind placebo-controlled trial did not reduce time to resolution or enhance fracture healing of CN. There was no added benefit of daily intervention with PTH (1-84) to below-knee casting in achieving earlier resolution of CN.

A Systematic Review of Angular Deformities in Charcot Neuroarthropathy

Charcot neuroarthropathy of the foot and ankle is associated with periarticular deformities and progressive radiographic changes. There have been studies analyzing the radiographic angulations and deformity progression in Charcot neuroarthropathy deformity. The aim of this paper is to provide systematic review of studies that evaluate foot and ankle radiographic parameters in patients with Charcot neuroarthropathy. A multidatabase search including, medline, EMBASE, Google Scholar, Cochrane Library, Clinicaltrials.gov and reference lists of included studies, was performed from 1980 to 2020. A total of 7 articles were included that analyzed radiographic angulations in Charcot neuroarthropathy deformity. The articles could be categorized into nonoperative angulation measurements, and pre- versus postoperative angulation measurements. The presence of ulcerations and the severity of the Charcot neuroarthropathy deformity were found to result from predominantly sagittal plane deformity. The deformity initiates with medial column collapse and progresses to continual lateral column collapse. Surgical intervention resulting in immediate postoperative improvement in angular measurements, however, without beaming of both the medial and lateral column, there was recurrence of the lateral column deformity. This systematic review of articles analyzing angular deformities in Charcot neuroarthropathy patients, demonstrates the progressive sagittal plane breakdown patterns of Charcot as well as the benefits of surgical intervention.

New Concepts in the Management of Charcot Neuroarthropathy in Diabetes

Charcot Neuroarthropathy (CN) is an uncommon, debilitating and often underdiagnosed complication of chronic diabetes mellitus though, it can also occur in other medical conditions resulting from nerve injury. Till date, the etiology of CN remains unknown, but enhanced osteoclastogenesis is believed to play a central role in the pathogenesis of CN, in the presence of neuropathy. CN compromises the overall health and quality of life. Delayed diagnosis can result in a severe deformity that can act as a gateway to ulceration, infection and in the worst case, can lead to limb loss. In an early stage of CN, immobilization with offloading plays a key role to a successful treatment. Medical therapies seem to have limited role in the treatment of CN.In case of severe deformity, proper footwear or bracing may help prevent further deterioration and development of an ulcer. In individuals with a concomitant ulcer with osteomyelitis, soft tissue infection and severe deformity, where conservative measures fall short, surgical intervention becomes the only choice of treatment. Early diagnosis and proper management at an early stage can help prevent the occurrence of CN and amputation.

Charcot Neuroarthropathy: From the Laboratory to the Bedside

BACKGROUND

The diabetic Charcot foot syndrome is a serious and potentially limbthreatening lower-extremity complication of diabetes.

INTRODUCTION

The present review provides a concise account of the advances made over the last twentyfive years in understanding the pathogenesis and management of Charcot neuroarthropathy (CN).

METHODS

In this study, the widely known pathogenetic mechanisms underpinning CN are brought into focus, particularly the role of RANKL/RANK/OPG system and advanced glycation end production in the pathogenesis of CN. Furthermore, other potential triggering factors, namely nitric oxide, endothelial dysfunction, macro calcifications and body weight that influence CN have also been discussed.

RESULTS

The wide range of diagnostic tools available to clinicians for accurate staging of this pathology has been examined, particularly radiological and nuclear medicine imaging. Additionally, the difficult differential diagnosis between osteomyelitis and CN is also elucidated.

CONCLUSION

The review concludes with the comprehensive summary of the major promising therapeutic strategies, including conservative treatment involving orthopedic devices, pharmacological approach, and the most common surgical techniques currently employed in the diagnosis and treatment of this acute disease.

Long-term effects on the progress of neuropathy after diabetic Charcot foot: an 8.5-year prospective case–control study

Objective

Charcot foot is a severe complication to diabetes mellitus, associated with diabetic neuropathy. Any long-term effects of a Charcot foot on the progress of neuropathy are still largely unexplored. The objective was to investigate whether a previous Charcot foot had any long-term effects on the progress of neuropathy.

Results

An 8.5-year follow-up case–control study of 49 individuals with diabetes mellitus, 24 of whom also had Charcot foot at baseline visit in 2005–2007. Neuropathy was assessed with a questionnaire, biothesiometry, heart rate variability and venous occlusion plethysmography. Of the 49 baseline participants, 22 were able to participate in the follow-up. Twelve had passed away in the meantime. Heart rate variability was unchanged in both groups; from 9.7 to 7.2 beats/min (p = 0.053) in the Charcot group, and 14.3 to 12.6 beats/min (p = 0.762) in the control group. Somato-sensoric neuropathy showed no difference between baseline and follow-up in the Charcot group (from 39.1 to 38.5 V) (p = 0.946), but a significantly worsened sensitivity in the control group (from 25.1 to 38.9 V) (p = 0.002). In conclusion, we found that any differences in somatic or cardial autonomic neuropathy present at baseline had disappeared at follow-up after 8.5 years.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3253-5) contains supplementary material, which is available to authorized users.

Musculoskeletal problems in diabetes mellitus

Diabetic patients may suffer from a wide range of musculoskeletal disorders that can cause pain and some dysfunctions in the patient and affect the treatment negatively or reduce the quality of life by causing problems in the implementation of exercise programs, which are very important in the treatment of patients with Diabetes Mellitus. Although most of these problems are also seen in non-diabetics, they are more frequently observed but are not specific to diabetics. Their physiopathology is not fully understood; there is some evidence suggesting that macro- and microvascular complications of diabetes are responsible. A diagnosis of musculoskeletal dysfunctions in diabetic patients is made by clinical findings, and there is currently no specific treatment. If the treatment of problems requires corticosteroid use, diabetes can be hard to manage. In this review, we summarized the general features, diagnosis, and treatment modalities of frequent and important musculoskeletal disorders in diabetic patients.

Updates on Diabetic Foot and Charcot Osteopathic Arthropathy

PURPOSE OF REVIEW

Diabetes mellitus affects approximately 30.8 million people currently living in the USA. Chronic diabetes complications, including diabetic foot complications, remain prevalent and challenging to treat. We review clinical diagnosis and challenges providers may encounter when managing diabetic foot ulcers and Charcot neuroarthropathy.

RECENT FINDINGS

Mechanisms controlling these diseases are being elucidated and not fully understood. Offloading is paramount to heal and manage diabetic foot ulcers and Charcot neuroarthropathy. Diabetic foot ulcers recur and the importance of routine surveillance and multidisciplinary approach is essential. Several predictors of failure in Charcot foot include a related diabetic foot ulcer, midfoot or rearfoot location of the Charcot event, and progressive bony changes on interval radiographs. Patients with diabetic foot ulcer and/or Charcot neuroarthropathy are in need of consistent and regular special multidisciplinary care. If not diagnosed early and managed effectively, morbidity and mortality significantly increase.

Short-term foot complications in Charcot neuroarthropathy: A retrospective study in tertiary care centres in Spain

OBJECTIVES

To assess the clinical characteristics of patients with Charcot neuroarthropathy (CN) in Spain and to identify predictors for CN-related complications.

PATIENTS AND METHODS

A retrospective study was conducted at five tertiary hospitals with diabetic foot care units in Spain. Data were collected from 83 patients, including demographic profiles, foot factors, diabetes characteristics, and presence of microvascular and macrovascular comorbidity, and a podiatric examination was also performed. Logistic regression analyses were used to determine significant predictors of the predefined clinical events.

RESULTS

Signs of diabetic neuropathy were found in almost all patients (98.9%) at the initial assessment, approximately half of them had diabetic retinopathy or nephropathy (61.5% and 51.8%, respectively), and peripheral artery disease was uncommon (8.6%). Thirty-eight patients (47.5%) experienced one or more relevant clinical events: 22 (27.5%) a new foot ulcer; 7 (8.7%) a major amputation; 20 (25%) were admitted to hospital; and 4 (5%) died. Only the presence of diabetic nephropathy was independently associated to development of any of the complications studied (p = 0.009; odds ratio = 3.37; 95% CI: 1.12-10.1).

CONCLUSIONS

Almost half the patients with CN attending specialised foot care units in tertiary hospitals experienced short-term CN-associated complications, and the risk was 3 times higher in those with a history of diabetic nephropathy.

A review of bone metabolism and developments in medical treatment of the diabetic Charcot foot

Charcot foot is a rare but severe, and possibly limb-threatening, complication to neuropathy and diabetes mellitus. The current treatment consists of long-term off-loading, and has a large negative impact on the patient's life. Much research has gone into understanding the condition and its biochemical mechanisms, however, the underlying pathogenesis of a Charcot foot is not yet fully understood. In the recent decades several key advances in our understanding of the Charcot foot have been made, both in regards to the changes in bone metabolism and structure an acute Charcot foot can cause, and to the molecular pathways involved in this. This review summerizes the available research into the bone metabolism around a Charcot foot, with an emphasis on the biochemical profile. The existing data regarding attempts at medical treatment is also reviewed, including novel trials targetting specific inflammatory pathways upregulated in the acute diabetic Charcot foot.

Bone mineral density and markers of bone turnover and inflammation in diabetes patients with or without a Charcot foot: An 8.5-year prospective case-control study

BACKGROUND AND AIMS

Charcot foot is a rare but severe complication to diabetes and peripheral neuropathy. It is still unclear if an acute Charcot foot has long-term effects on the bone metabolism. To investigate this, we conducted a follow-up study to examine if a previously acute Charcot foot has any long-term effects on bone mineral density (BMD) or local or systemic bone metabolism.

METHODS

An 8.5-year follow-up case-control study of 44 individuals with diabetes mellitus, 24 of whom also had acute or chronic Charcot foot at the baseline visit in 2005-2007, who were followed up in 2015 with DXA scans and blood samples.

RESULTS

21 of the 44 baseline participants participated in the follow-up. There were no difference in the change in total hip BMD from baseline to follow-up in either the Charcot or the control group (p = 0.402 and 0.517), and no increased risk of osteoporosis in the previous Charcot feet either. From baseline to follow-up, there was a significant difference in the change in levels of fsRANK-L in the Charcot group, but not in the control group (p = 0.002 and 0.232, respectively). At follow-up, there were no differences in fsRANK-L between the groups. The fsRANK-L/OPG ratio also significantly decreased from baseline to follow-up in the Charcot group (3.4 versus 0.5) (p = 0.009), but not in the control group (1.3 versus 1.1) (p = 0.302).

CONCLUSION

We found that diabetes patients with an acute Charcot foot have an elevated fsRANK-L/OPG ratio, and that the level decreased from baseline to follow-up to be comparable to the level in diabetes patients without previous or current Charcot foot. We found no permanent effect of an acute Charcot foot on hip or foot BMD.

Markers of Local Inflammation and Bone Resorption in the Acute Diabetic Charcot Foot

OBJECTIVE

Due to the localized nature of Charcot foot, systemically altered levels of inflammation markers can be difficult to measure. The aim of this study was to investigate whether it is possible to detect an arteriovenous (A-V) flux in any locally produced inflammatory biomarkers from an acute Charcot foot by comparing local and systemic measurements.

METHODS

We included patients with acute diabetic Charcot foot. Blood was sampled from the vena saphena magna on the distal part of the crus bilaterally as well as from the arteria radialis. To minimize the A-V shunting effect, the feet were externally cooled with ice water prior to resampling.

RESULTS

Both before and after cooling, the A-V flux of interleukin-6 (IL-6) between the Charcot feet and the arterial level was significantly higher than the flux between the healthy feet and the arterial level (Δvalue_before: 7.25 versus 0.41 pg/mL, resp., p = 0.008; Δvalue_after: 10.04 versus 1.68 pg/mL, resp., p = 0.032). There were no differences in the fluxes for other markers of inflammation.

CONCLUSION

We have found an increased A-V flux of IL-6 in the acute diabetic Charcot foot compared to the healthy foot in the same patients.

Treatment of Charcot Neuroarthropathy and osteomyelitis of the same foot: a retrospective cohort study

BACKGROUND

We evaluated treatment of osteomyelitis in the foot in the presence of Charcot neuroarthropathy, a devastating condition with progressive degeneration and joint destruction. We hypothesized that there was a difference in (1) amputation rate, (2) amputation level, (3) duration of antibiotic therapy, and (4) duration of immobilization for treatment of osteomyelitis within versus outside the Charcot zone.

METHODS

Forty patients (43 ft) diagnosed with Charcot neuroarthropathy and osteomyelitis of the same foot were retrospectively analyzed. Some patients were successfully treated for osteomyelitis at different sites on the same foot at different times, thus 60 cases of osteomyelitis were identified in 40 treated patients. Cases were divided according to osteomyelitis localization: Group 1 had osteomyelitis outside the active Charcot region; Group 2 had osteomyelitis within the active Charcot region.

RESULTS

Male patients (n = 29; mean age 58.2, range 40.1 to 77.5 years) were younger than female patients (n = 11; mean age 70.4, range 51.4 to 87.5, p = 0.02 years). Amputation rate was 52% overall (26/40 patients; 26/43 ft): 63% of 30 Group 1 cases and 40% of 30 Group 2 cases (p = 0.09). Amputation level (p = 0.009), duration of antibiotic treatment (p = 0.045) and duration of immobilization (p = 0.01) differed significantly between the groups.

CONCLUSIONS

Osteomyelitis within the Charcot region is associated with a higher level of amputation and longer durations of antibiotic therapy and immobilization. Osteomyelitis outside and within the Charcot affected region should be considered separately. If osteomyelitis occurs outside the active Charcot region, primary amputation may be preferred to internal resection.

LEVEL OF EVIDENCE

Retrospective cohort chart review study.

Conservative and Pharmacologic Treatments for the Diabetic Charcot Foot

Charcot neuroarthropathy is a disabling complication of diabetic neuropathy. Prolonged immobilization in a total contact cast (TCC) is among the main treatments. Education of health care professionals in the application of TCC together with well-conducted clinical trials are required to overcome its frequent underuse. There are no established pharmacologic therapies to treat this condition; however, there is an overwhelming need for a new therapeutic approach. Novel targeted drug delivery systems are required to prevent the pathologic bone and joint destruction of the Charcot neuroarthropathy and this may lead to an improved outcome in diabetic patients with this condition.

Novel Semiquantitative Bone Marrow Oedema Score and Fracture Score for the Magnetic Resonance Imaging Assessment of the Active Charcot Foot in Diabetes

There are no accepted methods to grade bone marrow oedema (BMO) and fracture on magnetic resonance imaging (MRI) scans in Charcot osteoarthropathy. The aim was to devise semiquantitative BMO and fracture scores on foot and ankle MRI scans in diabetic patients with active osteoarthropathy and to assess the agreement in using these scores. Three radiologists assessed 45 scans (Siemens Avanto 1.5T, dedicated foot and ankle coil) and scored independently twenty-two bones (proximal phalanges, medial and lateral sesamoids, metatarsals, tarsals, distal tibial plafond, and medial and lateral malleoli) for BMO (0-no oedema, 1-oedema < 50% of bone volume, and 2-oedema > 50% of bone volume) and fracture (0-no fracture, 1-fracture, and 2-collapse/fragmentation). Interobserver agreement and intraobserver agreement were measured using multilevel modelling and intraclass correlation (ICC). The interobserver agreement for the total BMO and fracture scores was very good (ICC = 0.83, 95% confidence intervals (CI) 0.76, 0.91) and good (ICC = 0.62; 95% CI 0.48, 0.76), respectively. The intraobserver agreement for the total BMO and fracture scores was good (ICC = 0.78, 95% CI 0.6, 0.95) and fair to moderate (ICC = 0.44; 95% CI 0.14, 0.74), respectively. The proposed BMO and fracture scores are reliable and can be used to grade the extent of bone damage in the active Charcot foot.

Inflammation as a Therapeutic Target for Diabetic Neuropathies

Diabetic neuropathies (DNs) are one of the most prevalent chronic complications of diabetes and a major cause of disability, high mortality, and poor quality of life. Given the complex anatomy of the peripheral nervous system and types of fiber dysfunction, DNs have a wide spectrum of clinical manifestations. The treatment of DNs continues to be challenging, likely due to the complex pathogenesis that involves an array of systemic and cellular imbalances in glucose and lipids metabolism. These lead to the activation of various biochemical pathways, including increased oxidative/nitrosative stress, activation of the polyol and protein kinase C pathways, activation of polyADP ribosylation, and activation of genes involved in neuronal damage, cyclooxygenase-2 activation, endothelial dysfunction, altered Na(+)/K(+)-ATPase pump function, impaired C-peptide-related signaling pathways, endoplasmic reticulum stress, and low-grade inflammation. This review summarizes current evidence regarding the role of low-grade inflammation as a potential therapeutic target for DNs.

Acute Charcot neuro-osteoarthropathy

Charcot neuro-osteoarthropathy (CN) is one of the most challenging foot complications in diabetes. Common predisposing and precipitating factors include neuropathy and increased mechanical forces, fracture and bone resorption, trauma and inflammation. In the last 15 years, considerable progress has been made in the early recognition of the acute Charcot foot when the X ray is still negative (stage 0 or incipient Charcot foot). Recent advances in imaging modalities have enabled the detection of initial signs of inflammation and underlying bone damage before overt bone and joint destruction has occurred. Casting therapy remains the mainstay of medical therapy of acute CN. If timely instituted, offloading can arrest disease activity and prevent foot deformity. In cases with severe deformity, modern surgical techniques can correct the unstable deformity for improved functional outcome and limb survival. Emerging new studies into the cellular mechanisms of severe bone destruction have furthered our understanding of the mechanisms of pathological bone and joint destruction in CN. It is hoped that these studies may provide a scientific basis for new interventions with biological agents.

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.

Intramedullary fixation in severe Charcot osteo-neuroarthropathy with foot deformity results in adequate correction without loss of correction - Results from a multi-centre study

BACKGROUND

Charcot osteo-neuroarthropathy (CN) of the foot can induce severe instability and deformity. Results of a consecutive clinical multi-centre study with Midfoot Fusion Bolt (MFB, Synthes GmbH, Oberdorf, Switzerland) are reported.

METHODS

All patients (aged 18 years and older) treated between 2009 and 2013 with surgical reconstruction of the midfoot with MFB for CN were included. Demographics, pre-surgical health status, details of foot pathology, details of surgery, postoperative treatment, treatment failure, and adverse events were registered. The following radiographic angles were measured on pre-op, post-op and last follow-up radiographs: talo-1st metatarsal (TMT) angle dorsoplantar and lateral view, and calcaneo-5th metatarsal angle.

RESULTS

Forty-seven patients (48 feet) were included in three centres. In 38 patients (80.1%) diabetes was diagnosed. Wound healing problems occurred in 21% of patients and recurrent ulceration in 13%. Revision surgery for loss of correction was performed in three cases (6%). Union rate at final follow-up was 98%. Major amputation for deep infection was performed in two patients (4%), minor amputation at the foot level in three cases (6%). Failure was more frequent when only one MFB (instead of 2 or 3) was used and no Gastrocnemius lengthening was performed. Radiographic alignment significantly improved pre- versus postoperatively and preoperatively versus follow-up.

CONCLUSIONS

Realignment and fixation with MFB in severe CN result in adequate correction with minimal loss of correction in the observed clinical course. The non-union rate was lower than previously reported. Stable fixation with MFB is a valuable treatment option for CN with minimal loss of correction and high union rates. The use of a minimum of two bolts is recommended to avoid recurrent deformity. Clinical Trials.gov: NCT01770639.

Lower limb complications of diabetes mellitus: a comprehensive review with clinicopathological insights from a dedicated high-risk diabetic foot multidisciplinary team

Diabetic complications in the lower extremity are associated with significant morbidity and mortality, and impact heavily upon the public health system. Early and accurate recognition of these abnormalities is crucial, enabling the early initiation of treatments and thus avoiding or minimizing deformity, dysfunction and amputation. Following careful clinical assessment, radiological imaging is central to the diagnostic and follow-up process. We aim to provide a comprehensive review of diabetic lower limb complications designed to assist radiologists and to contribute to better outcomes for these patients.

Charcot osteoarthropathy in type 2 diabetes persons presenting to specialist diabetes clinic at a tertiary care hospital

BACKGROUND

Charcot osteoarthropathy or charcot foot is a rare, chronic, non-communicable condition of bones and joints which may results into severe deformity and more prone to develop ulcers possibly leading to amputation. The purpose of this study was to determine the prevalence of Charcot osteoarthropathy and its association with age, BMI, gender, duration of diabetes, HBA1c and peripheral neuropathy.

METHODS

A total of 1931 subjects with type 2 diabetes having mean age 50.72 ± 10.66 years presenting in a specialist diabetes clinic at shalamar hospital, Lahore, Pakistan were enrolled. The diagnosis of Charcot osteoarthropathy was made by examination of both dorsal and plantar surfaces of foot for swelling, erythema, increase in temperature and any musculoskeletal deformity which was later confirmed by radiographs. Assessment of neuropathy was carried out by checking the sense of pressure, joint position and vibration. BMI (Body Mass Index), fasting blood glucose (FBG) and HbA1C were determined.

RESULTS

In all subjects including male 704 (36.45 %) and female 1227 (63.55 %), 0.4 % subjects had charcot deformity, while 0.2 %, 0.15 % and 0.05 % subjects having right, left and bilateral deformity respectively. Bilaterally symmetrical neuropathy was diagnosed in 25.4 % in subjects. There was a significant association (p < 0.05) of deformity with duration of diabetes, HbA1C and neuropathy, however no significant association (p > 0.05) was found with age, BMI, weight, height and gender.

CONCLUSION

There is a need to have a special care of persons with diabetes regarding blood glucose control and development of peripheral neuropathy. Early identification and management of risk factors may prevent the occurrence of charcot deformity. Patients must be educated about the foot care.

Inflammatory and bone turnover markers in a cross-sectional and prospective study of acute Charcot osteoarthropathy

AIMS

To assess markers of inflammation and bone turnover at presentation and at resolution of Charcot osteoarthropathy.

METHODS

We measured serum inflammatory and bone turnover markers in a cross-sectional study of 35 people with Charcot osteoarthropathy, together with 34 people with diabetes and 12 people without diabetes. In addition, a prospective study of the subjects with Charcot osteoarthropathy was conducted until clinical resolution.

RESULTS

At presentation, C-reactive protein (P = 0.007), tumour necrosis factor-α (P = 0.010) and interleukin-6 (P = 0.002), but not interleukin-1β, (P = 0.254) were significantly higher in people with Charcot osteoarthropathy than in people with and without diabetes. Serum C-terminal telopeptide (P = 0.004), bone alkaline phosphatase (P = 0.006) and osteoprotegerin (P < 0.001), but not tartrate-resistant acid phosphatase (P = 0.126) and soluble receptor activator of nuclear factor-κβ ligand (P = 0.915), were significantly higher in people with Charcot osteoarthropathy than in people with and without diabetes. At follow-up it was found that tumour necrosis factor-α (P = 0.012) and interleukin-6 (P = 0.003), but not C-reactive protein (P = 0.101), interleukin-1β (P = 0.457), C-terminal telopeptide (P = 0.743), bone alkaline phosphatase (P = 0.193), tartrate-resistant acid phosphatase (P = 0.856), osteoprotegerin (P = 0.372) or soluble receptor activator of nuclear factor-kβ ligand (P = 0.889), had significantly decreased between presentation and the 3 months of casting therapy time point, and all analytes remained unchanged from 3 months of casting therapy until resolution. In people with Charcot osteoarthropathy, there was a positive correlation between interleukin-6 and C-terminal telopeptide (P = 0.028) and tumour necrosis factor-α and C-terminal telopeptide (P = 0.013) only at presentation.

CONCLUSIONS

At the onset of acute Charcot foot, serum concentrations of tumour necrosis factor-α and interleukin-6 were elevated; however, there was a significant reduction in these markers at resolution and these markers may be useful in the assessment of disease activity.

Inhibition of TNF-α Reverses the Pathological Resorption Pit Profile of Osteoclasts from Patients with Acute Charcot Osteoarthropathy

We hypothesised that tumour necrosis factor-α (TNF-α) may enhance receptor activator of nuclear factor-κβ ligand- (RANKL-) mediated osteoclastogenesis in acute Charcot osteoarthropathy. Peripheral blood monocytes were isolated from 10 acute Charcot patients, 8 diabetic patients, and 9 healthy control subjects and cultured in vitro on plastic and bone discs. Osteoclast formation and resorption were assessed after treatment with (1) macrophage-colony stimulating factor (M-CSF) and RANKL and (2) M-CSF, RANKL, and neutralising antibody to TNF-α (anti-TNF-α). Resorption was measured on the surface of bone discs by image analysis and under the surface using surface profilometry. Although osteoclast formation was similar in M-CSF + RANKL-treated cultures between the groups (p > 0.05), there was a significant increase in the area of resorption on the surface (p < 0.01) and under the surface (p < 0.01) in Charcot patients compared with diabetic patients and control subjects. The addition of anti-TNF-α resulted in a significant reduction in the area of resorption on the surface (p < 0.05) and under the surface (p < 0.05) only in Charcot patients as well as a normalisation of the aberrant erosion profile. We conclude that TNF-α modulates RANKL-mediated osteoclastic resorption in vitro in patients with acute Charcot osteoarthropathy.

Personalized orthoses as a good treatment option for Charcot neuro-osteoarthropathy of the foot

BACKGROUND

We sought to assess the biomechanical characteristics of the feet of patients with Charcot neuro-osteoarthropathy and to determine reulceration rates before and after personalized conservative orthotic treatment.

METHODS

A longitudinal prospective study was performed in 35 patients with Charcot's foot. Although some patients had a history of ulcers, at the study outset no patient had ulcers. All of the patients underwent biomechanical testing and a radiographic study. A radiophotopodogram was prepared by superimposing an imprint of the sole on a plantar radiograph. Based on the results of these tests, an orthopedic insole was prepared and therapeutic footwear prescribed for each foot. The following variables were compared between the Charcot and unaffected feet: previous ulcers and ulcer sites, reulcerations produced after treatment, type of foot (neuropathic/neuroischemic), ankle mobility, first-ray mobility, and relaxed calcaneal stance position. Treatment efficacy was determined by comparing ulcers presenting in patients in the year leading up to the study period and the year in which treatment was received.

RESULTS

In a 1-year period, 70 feet received orthotic treatment, of which 41 were Charcot's feet. Ulceration rates before the study were 73.2% in feet with Charcot's and 31.0% in those without. After 1 year of wearing the customized orthoses, rates fell significantly to 9.8% in the Charcot feet and 0% in the feet without this condition.

CONCLUSIONS

Conservative customized orthotic treatment was effective at preventing ulcers and the complications that often lead these patients to surgery.

Neuropathy and the vascular-bone axis in diabetes: lessons from Charcot osteoarthropathy

Emerging evidence from the last two decades has shown that vascular calcification (VC) is a regulated, cell-mediated process orchestrated by vascular smooth muscle cells (VSMCs) and that this process bears many similarities to bone mineralization. While many of the mechanisms driving VSMC calcification have been well established, it remains unclear what factors in specific disease states act to promote vascular calcification and in parallel, bone loss. Diabetes is a condition most commonly associated with VC and bone abnormalities. In this review, we describe how factors associated with the diabetic milieu impact on VSMCs, focusing on the role of oxidative stress, inflammation, impairment of the advanced glycation end product (AGE)/receptor for AGE system and, importantly, diabetic neuropathy. We also explore the link between bone and VC in diabetes with a specific emphasis on the receptor activator of nuclear factor κβ ligand/osteoprotegerin system. Finally, we describe what insights can be gleaned from studying Charcot osteoarthropathy, a rare complication of diabetic neuropathy, in which the occurrence of VC is frequent and where bone lysis is extreme.

Novel use of a Dektak 150 surface profiler unmasks differences in resorption pit profiles between control and Charcot patient osteoclasts

We hypothesized that newly formed osteoclasts from patients with acute Charcot osteoarthropathy can resorb surfaces of bone more extensively compared with controls. Peripheral blood monocytes, isolated from eight Charcot patients and nine controls, were cultured in vitro on 24-well plates and bovine bone discs in duplicate with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κβ ligand (RANKL). Osteoclast formation was assessed by tartrate-resistant acid phosphatase staining (TRAcP) at day 17. Resorption was measured at day 21 after toluidine blue staining by two methods: (1) area of resorption at the surface by image analysis (%) and (2) area of resorption under the surface (μm(2)) measured by a Dektak 150 Surface Profiler. Ten 1,000 μm-long scans were performed per disc. Pits were classified as unidented, bidented, and multidented according to their shape. Although the number of newly formed TRAcP positive multinucleated cells (>3 nuclei) was similar in M-CSF + RANKL-treated cultures between controls and Charcot patients, the latter exhibited increased resorbing activity. The area of resorption on the surface by image analysis was significantly greater in Charcot patients compared with controls (21.1 % [14.5-26.2] vs. 40.8 % [35.4-46.0], median [25-75th percentile], p < 0.01), as was the area of resorption under the surface (2.7 x 10(3) μm(2) [1.6 x 10(3)- 3.9 x 10(3)] vs. 8.3 x 10(3) μm (2) [5.6 x 10(3)- 10.6 x 10(3), [corrected] p < 0.01) after profilometry. In Charcot patients pits were deeper and wider and more frequently presented as multidented pits. This application of the Dektak 150 Surface Profiler revealed novel differences in resorption pit profile from osteoclasts derived from Charcot patients compared with controls. Resorption in Charcot patients was mediated by highly aggressive newly formed osteoclasts from monocytes eroding large and deep areas of bone.

Charcot neuroarthropathy of the foot and ankle: diagnosis and management strategies

This article reviews current literature discussing the etiology, pathophysiology, diagnosis and imaging, and conservative and surgical treatment of Charcot osteoarthropathy. The treatment of Charcot osteoarthropathy with concurrent osteomyelitis is also discussed.

Charcot neuroarthropathy in simultaneous kidney-pancreas transplantation: report of two cases

Charcot neuroarthropathy (CN) is considered a major complication in diabetes mellitus (DM), and it is estimated that 1% of diabetic patients may develop this complication. Simultaneous kidney–pancreas transplantation (SKPT) is one of the most effective therapies for patients with type 1 DM and end-stage diabetic nephropathy. Some cases with a Charcot-modified clinical presentation during the postoperative convalescence period after SKPT have been described. The clinical presentation may condition severe destructive lesions, and good practices include systematic follow-up. Based on the cases described, SKPT is one more entity that might lead to CN ‘foot-at-risk’. The aim of this article is to describe two cases of neuropathic arthropathy with rapid progression in the short term after SKPT.

An overview of the Charcot foot pathophysiology

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.

Developing an evidence-based clinical pathway for the assessment, diagnosis and management of acute Charcot Neuro-Arthropathy: a systematic review

BACKGROUND

Charcot Neuro-Arthropathy (CN) is one of the more devastating complications of diabetes. To the best of the authors' knowledge, it appears that no clinical tools based on a systematic review of existing literature have been developed to manage acute CN. Thus, the aim of this paper was to systematically review existing literature and develop an evidence-based clinical pathway for the assessment, diagnosis and management of acute CN in patients with diabetes.

METHODS

Electronic databases (Medline, PubMed, CINAHL, Embase and Cochrane Library), reference lists, and relevant key websites were systematically searched for literature discussing the assessment, diagnosis and/or management of acute CN published between 2002-2012. At least two independent investigators then quality rated and graded the evidence of each included paper. Consistent recommendations emanating from the included papers were then fashioned in a clinical pathway.

RESULTS

The systematic search identified 267 manuscripts, of which 117 (44%) met the inclusion criteria for this study. Most manuscripts discussing the assessment, diagnosis and/or management of acute CN constituted level IV (case series) or EO (expert opinion) evidence. The included literature was used to develop an evidence-based clinical pathway for the assessment, investigations, diagnosis and management of acute CN.

CONCLUSIONS

This research has assisted in developing a comprehensive, evidence-based clinical pathway to promote consistent and optimal practice in the assessment, diagnosis and management of acute CN. The pathway aims to support health professionals in making early diagnosis and providing appropriate immediate management of acute CN, ultimately reducing its associated complications such as amputations and hospitalisations.

Etiology, pathophysiology and classifications of the diabetic Charcot foot

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.

Medical management of Charcot arthropathy

Charcot arthropathy is a major complication of diabetes and it poses management challenges to health care professionals. Early diagnosis and timely intervention are essential for improved outlook of these patients. Casting therapy has been accepted as the mainstay treatment of the acute Charcot foot, although there are still controversies regarding its duration, the choice of removable and non-removable device and weight-bearing casts vs. non-weight-bearing casts. Two groups of antiresorptive therapies have been evaluated in the treatment of the acute Charcot foot, bisphosphonates (intravenous and oral) and calcitonin. These therapies have clearly shown a reduction of bone turnover, although, they have not shown a significant effect on temperature reduction. Current evidence to support their use is weak. An anabolic agent to speed up clinical resolution and fracture healing may be helpful and a clinical trial to evaluate the possible benefit of 1-84 recombinant human parathyroid hormone on fracture healing in the acute Charcot foot is in progress. This paper summarises the current approach to medical management of acute Charcot arthropathy with specific emphasis on casting and pharmacological therapy. Emerging new studies of the pathogenesis of this condition are also discussed.

The Charcot joint: a modern neurologic perspective

The Charcot joint, or Charcot neuroarthropathy, is a syndrome that was described over 140 years ago but one with very little exposure in the neurologic literature. We present a case recently seen and then discuss the history, epidemiology, pathophysiology, clinical features, and diagnosis of acute and chronic Charcot joint disease with particular emphasis on the value and limitations of imaging. A diagnostic algorithm is proposed. We also review the therapeutic strategies available for acute and chronic Charcot joints with a treatment algorithm. This review is aimed at enhancing the awareness of neurologists regarding Charcot neuroarthropathy, because they are often the principal caregivers for patients with peripheral neuropathy. We hope to promote early detection of acute Charcot neuroarthropathy, thereby reducing or preventing the bony deformation of chronic Charcot neuroarthropathy.

Plantar Temperature Response to Walking in Diabetes with and without Acute Charcot: The Charcot Activity Response Test

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.

Diagnostics and treatment of the diabetic foot

Every 30 s, a lower limb is amputated due to diabetes. Of all amputations in diabetic patients 85% are preceded by a foot ulcer which subsequently deteriorates to a severe infection or gangrene. There is a complexity of factors related to healing of foot ulcers including strategies for treatment of decreased perfusion, oedema, pain, infection, metabolic disturbances, malnutrition, non-weight bearing, wound treatment, foot surgery, and management of intercurrent disease. Patients with diabetic foot ulcer and decreased perfusion do often not have rest pain or claudication and as a consequence non-invasive vascular testing is recommended for early recognition of ulcers in need of revascularisation to achieve healing. A diabetic foot infection is a potentially limb-threatening condition. Infection is diagnosed by the presence or increased rate of signs inflammation. Often these signs are less marked than expected. Imaging studies can diagnose or better define deep, soft tissue purulent collections and are frequently needed to detect pathological findings in bone. The initial antimicrobial treatment as well as duration of treatment is empiric. There is a substantial delay in wound healing in diabetic foot ulcer which has been related to various abnormalities. Several new treatments related to these abnormalities have been explored in wound healing with various successes. An essential part of the strategy to achieve healing is an effective offloading. Many interventions with advanced wound management have failed due to not recognizing the need for effective offloading. A multidisciplinary approach to wounds and foot ulcer has been successfully implemented in different centres with a substantial decrease in amputation rate.

Charcot osteoarthropathy in diabetes: A brief review with an emphasis on clinical practice

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.

A prospective study of calcaneal bone mineral density in acute Charcot osteoarthropathy

OBJECTIVE

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.

RESULTS

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).

CONCLUSIONS

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.

Percutaneous bone biopsy to distinguish osteomyelitis from charcot osteoarthropathy: two case reports

Level of Evidence: V, Expert Opinion

[Neurogenic osteoarthropathy of the knee associated with spina bifida: a diagnosis not to be missed]

Neurogenic arthropathy is a severe complication of chronic sensitive deficits that occurred commonly in diabetic neuropathies. It is a destructive and painless osteoarthritis associated with a loss of the deep sensitivity and a defect of protective reactions against chronic articular microtraumatisms. We report a 55-year-old woman with neuroarthropathy of the knee resulting from a spina bifida. Bisphosphonate use is an effective but non-consensual treatment.

The Charcot foot: medical and surgical therapy

Charcot neuro-osteoarthropathy (CN) is among the most devastating complications of neuropathy and now most commonly occurs in the feet of diabetic patients. Because it is relatively rare and because most patients and practitioners do not expect major bone pathology in the absence of significant pain, CN is often misdiagnosed as cellulitis, deep venous thrombosis, or gout. Also, radiographs early in the process are often relatively unremarkable. Although MRI findings are characteristic, treatment should not wait for the MRI result. The hot swollen erythematous neuropathic foot suspected to be CN should be emergently mechanically protected, usually in an irremovable total contact cast. Mechanical protection is the mainstay of conservative therapy, but surgical reconstruction of a deformed foot can usually also be successful. Unless diagnosed very early, significant decrements in quality of life result. Controlled studies are urgently needed to identify best practices.