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

What the Physician Needs to Know about Charcot Arthropathy and Ankle Fracture Treatment Dilemma: A Case Report and a Possible Medical Approach and Treatment Algorithm

Introduction

Charcot arthropathy consists of a rapid and destructive complication of the joints following the loss of innervation caused by many complicated etiologies. Diabetic neuropathy has become the most common etiological factor.

Case Report

We present a case of a 64-year-old female patient with a history of chronic renal failure on hemodialysis, hypertension, hypothyroidism, and Type 2 diabetes, complicated with neuropathy and Charcot disease, who referred to our department. Initially, the patient was managed with a restraint orthotic device due to a bimalleolar ankle fracture. An unsuccessful treatment and the presence of a pressure ulcer with pus-like drainage on the lateral malleolus 2 months later led to the decision for a below-knee amputation.

Conclusion

High clinical suspicion by the attending physician may reduce the risk of complications and lead to proper treatment with better outcomes.

Charcot Foot Offloading in Stage 0 Is Associated With Shorter Total Contact Cast Treatment and Lower Risk of Recurrence and Reconstructive Surgery: A Pilot Study

OBJECTIVE

Charcot foot (CF) requires prolonged offloading of the affected foot to decrease the risk of deformity. The earliest phase in active CF (stage 0) is characterized by inflammatory signs without established fractures or skeletal deformity. We investigated whether offloading in stage 0 influences duration of total contact casting (TCC), risk of recurrence, and future need for surgery.

RESEARCH DESIGN AND METHODS

All patients treated for active CF at Skåne University Hospital (Lund, Sweden) between 2006 and 2019 were screened for participation in a retrospective cohort study. CF events of included patients were classified as stage 0 or 1 according to X-ray and MRI reports.

RESULTS

A total of 183 individuals (median age 61 [interquartile range (IQR) 52-68] years, 37% type 1 diabetes, 62% men) were followed for a median of 7.0 (IQR 3.9-11) years. In 198 analyzed CF events, 74 were treated with offloading in stage 0 and 124 in stage 1. Individuals offloading in stage 0 had significantly shorter TCC duration (median 75 [IQR 51-136] vs. 111.5 [72-158] days; P = 0.001). The difference was sustained when including only MRI-confirmed CF. The risk of developing new ipsilateral CF events >1 year after introduced definitive footwear was lower in those treated with offloading in stage 0 (2.7% vs. 9.7%; P < 0.05). No individual treated with offloading in stage 0 underwent reconstructive surgery, compared with 11 (8.9%) treated with offloading in stage 1 (P < 0.01). Amputation rates were similar.

CONCLUSIONS

Offloading in stage 0 CF was associated with shorter TCC treatment, lower risk of a new CF event, and diminished need for reconstructive surgery. Future amputation risk was not affected.

White noise insole: an artificial evoked sensation device that can be expected to improve plantar sensation of diabetic foot

Diabetic foot is a common severe complication of diabetes, and its main symptom is diabetic foot ulcer. The production of plantar diabetic foot ulcers is usually affected by two factors, namely neuropathy or vascular disease. While previous studies proved that stochastic resonance (SR) could effectively enhance the plantar touch of patients with diabetic feet, the potential impact of SR on neural circuit feedback, especially on the input of the tactile nerves of the lower limbs, is less clear. This study aims to explore the potential impact on the tactile threshold of the human foot when using vibrating insoles. We study a white noise vibration insole based on SR mechanism. We compare and analyze the tactile threshold voltage (TTV) triggered by an electrical stimulation device in three main plantar pressure-bearing areas (the second metatarsal (M2), the fourth metatarsal (M4), and the heel (H) area) of 8 participants using EEG and self-developed vibration insole. Significance found in M2 and M4 areas, white noise signal (WNS) lowered the tactile threshold in these areas, and had a potentially positive impact on patients with diabetic feet, especially in the M4 area. The influence of WNS on the plantar heel area was still controversial. This study showed that WNS applied to the sole could improve the plantar tactile sensing ability of patients with diabetic feet, but it did not cover all areas. The application of WNS showed better benefits for the forefoot area than for the hindfoot area, which was speculated that may be related to the difference in the distribution density of blood vessels in plantar areas. Due to the impaired natural touch in participants with diabetic foot, using artificial evoked sensation WNS intervention, would be a feasible approach to improve plantar sensation.

Muscle atrophy in diabetic patients with Charcot foot: a case-control study

PURPOSE

To evaluate the distribution and severity of muscle atrophy in diabetic patients with active Charcot foot (CF) compared to diabetic patients without CF. Furthermore, to correlate the muscle atrophy with severity of CF disease.

MATERIAL/METHODS

In this retrospective study, MR images of 35 diabetic patients (21 male, median:62.1 years ± 9.9SD) with active CF were compared with an age- and gender-matched control group of diabetic patients without CF. Two readers evaluated fatty muscle infiltration (Goutallier-classification) in the mid- and hindfoot. Furthermore, muscle trophic (cross-sectional muscle area (CSA)), intramuscular edema (none/mild versus moderate/severe), and the severity of CF disease (Balgrist Score) were assessed.

RESULTS

Interreader correlation for fatty infiltration was substantial to almost perfect (kappa-values:0.73-1.0). Frequency of fatty muscle infiltration was high in both groups (CF:97.1-100%; control:77.1-91.4%), but severe infiltration was significantly more frequent in CF patients (p-values: < 0.001-0.043). Muscle edema was also frequently seen in both groups, but significantly more often in the CF group (p-values: < 0.001-0.003). CSAs of hindfoot muscles were significantly smaller in the CF group. For the flexor digitorum brevis muscle, a cutoff value of 139 mm2 (sensitivity:62.9%; specificity:82.9%) in the hindfoot was found to differentiate between CF disease and the control group. No correlation was seen between fatty muscle infiltration and the Balgrist Score.

CONCLUSION

Muscle atrophy and muscle edema are significantly more severe in diabetic patients with CF disease. Muscle atrophy does not correlate with the severity of active CF disease. A CSA < 139 mm2 of the flexor digitorum brevis muscle in the hindfoot may indicate CF disease.

No Difference in Risk of Amputation or Frequency of Surgical Interventions Between Patients With Diabetic and Nondiabetic Charcot Arthropathy

BACKGROUND

The cause of Charcot neuro-osteoarthropathy (CN) is diabetes in approximately 75% of patients. Most reports on the clinical course and complications of CN focus on diabetic CN, and reports on nondiabetic CN are scarce. No study, to our knowledge, has compared the clinical course of patients initially treated nonoperatively for diabetic and nondiabetic CN.

QUESTIONS/PURPOSES

Among patients with CN, are there differences between patients with diabetes and those without in terms of (1) the frequency of major amputation as ascertained by a competing risks survivorship estimator; (2) the frequency of surgery as ascertained by a competing risks survivorship estimator; (3) frequency of reactivation, as above; or (4) other complications (contralateral CN development or ulcers)?

METHODS

Between January 1, 2006, and December 31, 2018, we treated 199 patients for diabetic CN. Eleven percent (22 of 199) were lost before the minimum study follow-up of 2 years or had incomplete datasets and could not be analyzed, and another 9% (18 of 199) were excluded for other prespecified reasons, leaving 80% (159 of 199) for analysis in this retrospective study at a mean follow-up duration since diagnosis of 6 ± 4 years. During that period, we also treated 78 patients for nondiabetic Charcot arthropathy. Eighteen percent (14 of 78) were lost before the minimum study follow-up and another 5% (four of 78 patients) were excluded for other prespecified reasons, leaving 77% (60 of 78) of patients for analysis here at a mean of 5 ± 3 years. Patients with diabetic CN were younger (59 ± 11 years versus 68 ± 11 years; p < 0.01), more likely to smoke cigarettes (37% [59 of 159] versus 20% [12 of 60]; p = 0.02), and had longer follow-up (6 ± 4 years versus 5 ± 3 years; p = 0.02) than those with nondiabetic CN. Gender, BMI, overall renal failure, dialysis, and presence of peripheral arterial disease did not differ between the groups. Age difference and length of follow-up were not considered disqualifying problems because of the later onset of idiopathic neuropathy and longer available patient follow-up in patients with diabetes, because our program adheres to the follow-up recommendations suggested by the International Working Group on the Diabetic Foot. Treatment was the same in both groups and included serial total-contact casting and restricted weightbearing until CN had resolved. Then, patients subsequently transitioned to orthopaedic footwear. CN reactivation was defined as clinical signs of the recurrence of CN activity and confirmation on MRI. Group-specific risks of the frequencies of major amputation, surgery, and CN reactivation were calculated, accounting for competing events. Group comparisons and confounder analyses were conducted on these data with a Cox regression analysis. Other complications (contralateral CN development and ulcers) are described descriptively to avoid pooling of complications with varying severity, which could be misleading.

RESULTS

The risk of major amputation (defined as an above-ankle amputation), estimated using a competing risks survivorship estimator, was not different between the diabetic CN group and nondiabetic CN group at 10 years (8.8% [95% confidence interval 4.2% to 15%] versus 6.9% [95% CI 0.9% to 22%]; p = 0.4) after controlling for potentially confounding variables such as smoking and peripheral artery disease. The risk of any surgery was no different between the groups as estimated by the survivorship function at 10 years (53% [95% CI 42% to 63%] versus 58% [95% CI 23% to 82%]; p = 0.3), with smoking (hazard ratio 2.4 [95% CI 1.6 to 3.6]) and peripheral artery disease (HR 2.2 [95% CI 1.4 to 3.4]) being associated with diabetic CN. Likewise, there was no between-group difference in CN reactivation at 10 years (16% [95% CI 9% to 23%] versus 11% [95% CI 4.5% to 22%]; p = 0.7) after controlling for potentially confounding variables such as smoking and peripheral artery disease. Contralateral CN occurred in 17% (27 of 159) of patients in the diabetic group and in 10% (six of 60) of those in the nondiabetic group. Ulcers occurred in 74% (117 of 159) of patients in the diabetic group and in 65% (39 of 60) of those in the nondiabetic group.

CONCLUSION

Irrespective of whether the etiology of CN is diabetic or nondiabetic, our results suggest that orthopaedic surgeons should use similar nonsurgical treatments, with total-contact casting until CN activity has resolved, and then proceed with orthopaedic footwear. A high frequency of foot ulcers must be anticipated and addressed as part of the treatment approach.

LEVEL OF EVIDENCE

Level III, prognostic study.

Pedobarographic evaluation of five commonly used orthoses for the lower extremity

INTRODUCTION

Orthoses are designed to achieve immobilization or off-loading of certain regions of the foot. Yet, their off-loading capacity for the specific regions has not yet been studied. Therefore, the aim of this study was to analyze the plantar pressure distribution of five commonly applied orthoses for foot and ankle in a healthy population.

MATERIALS AND METHODS

Five orthoses (postoperative shoe, forefoot relief shoe, short walker boot, high walker boot, and calcaneus fracture orthosis) were compared pedobarographically using insoles on a treadmill to a ready-made running shoe in eleven healthy subjects (median age 29 years). Peak pressure, maximum force, force-time integral, contact time, and contact area were evaluated separately for the forefoot, midfoot, and hindfoot.

RESULTS

The forefoot relief shoe, the short- and high walker boot significantly reduced the peak pressure at the forefoot with no significant differences between these orthoses. None of the five orthoses off-loaded the midfoot, but the calcaneus fracture orthosis and the short walker boot instead increased midfoot load. For the hindfoot, the calcaneus fracture orthosis was the only device to significantly reduce the peak pressure.

CONCLUSIONS

This is the first study to investigate the specific off-loading capacities of different orthoses for specific foot regions in a healthy collective. The knowledge of absolute and relative load shifts for the different orthoses is of fundamental interest for targeted clinical decision-making of physicians.

Histopathological assessment of a two-stage reconstructive procedure of the infected Charcot foot

INTRODUCTION

Charcot neuropathic osteoarthropathy (CN) can be complicated by osteomyelitis (OM). Surgery is a standard procedure to treat OM including debridement and interposition of antibiotic-loaded cement (ABLC) spacer. The course of CN and OM was investigated on a histopathological level.

MATERIALS AND METHODS

Diabetic patients (n = 15) suffering from CN and midfoot OM underwent surgical debridement and interposition of ABLC was interposed. 6 weeks later, ABLC was removed and bone samples were taken again. Histopathological Charcot Score (HCS), Histopathological Osteomyelitis Evaluation Score (HOES) and microbiological assessment were used to evaluate osteomyelitic and neuroosteoarthropathic activity at both time points.

RESULTS

Interposition of ABLC leads to microbiological/histopathological eradication of OM in 73%/87% of patients. CN activity-measured by HCS-could be reduced from moderate to low activity by ABLC spacer and correlated with HOES.

CONCLUSIONS

CN activity could be reduced by surgery. It can be suggested that neuroosteoarthropathic activity measured by HCS is triggered by OM.

Nonoperative Treatment of Charcot Neuro-osteoarthropathy

Conservative treatment of Charcot neuro-osteoarthropathy (CN) aims to retain a stable, plantigrade, and ulcer-free foot, or to prevent progression of an already existing deformity. CN is treated with offloading in a total contact cast as long as CN activity is present. Transition to inactive CN is monitored by the resolution of clinical activity signs and by resolution of bony edema in MRI. Fitting of orthopedic depth insoles, orthopedic shoes, or ankle-foot orthosis should follow immediately after offloading has ended to prevent CN reactivation or ulcer development.

Staged Percutaneous Treatment of a Complete Lisfranc Dislocation Secondary to Charcot Arthropathy: A Case Report

CASE

A 36-year-old woman with diabetic neuropathy presented with complete dorsal dislocation of the midfoot secondary to Charcot arthropathy. She was treated in a staged fashion with a Taylor spatial butt frame to distract and reduce the midfoot followed by percutaneous preparation of the tarsometatarsal (TMT) joints and fixator-assisted fusion. The arthrodesis healed successfully with maintenance of function at the 30-month follow-up.

CONCLUSION

Staged treatment with a Taylor spatial frame can be used successfully to treat complete TMT dislocations in the setting of Charcot arthropathy. Complications are not uncommon and must be addressed appropriately.

Treatment Failures in Diabetic Foot Osteomyelitis Associated with Concomitant Charcot Arthropathy: The Role of Underlying Arteriopathy

OBJECTIVE

Therapy for diabetic foot osteomyelitis (DFO) with Charcot neuroosteoarthropathy is challenging. In patients with diabetic Charcot osteomyelitis (DCO), both the anatomic deformity and infection must be addressed. This study assessed the outcomes of DCO therapy and variables associated with treatment failure and compared them with outcomes of DFO cases.

METHODS

A single-center, retrospective, case-control study was performed to compare 93 DCO episodes with 530 DFO episodes, using Kaplan-Meier survival curves and multivariate Cox regression analyses.

RESULTS

Clinical failure occurred in 21.5% of DCO compared with 22.3% in DFO episodes (p=0.89) and was associated with peripheral arterial disease (PAD) stages 3 or 4 (HR 6.1; CI 2.0-18.1) and chronic treatment with immunosuppressives (HR 7.4; CI 2.0-27.1). Major amputations were significantly more frequent in DCO (28% versus 13.6%; p<0.01) and associated with PAD stages 3 and 4 (HR 8.0; CI 2.2-29.4), smoking (HR 5.4; CI 1.2-24.6), alcohol abuse (HR 3.5; CI 1.1-10.6), and renal dialysis (HR 4.9; CI 1.3-18.9).

CONCLUSIONS

Clinical treatment failures did not differ between DCO and DFO. However, patients with DCO underwent major amputation twice as often as those with DFO. Unlike widespread belief, treatment failure in DCO patients may, similar to DFO, be associated with a striking epidemiological link to severe PAD.