Follow up of MRI bone marrow edema in the treated diabetic Charcot foot – a review of patient charts

Abstract

Background: Ill-defined areas of water-like signal on bone magnetic resonance imaging (MRI), characterized as bone marrow edema or edema-equivalent signal-changes (EESC), is a hallmark of active-stage pedal neuro-osteoarthropathy (Charcot foot) in painless diabetic neuropathy, and is accompanied by local soft-tissue edema and hyperthermia. The longitudinal effects on EESC of treating the foot in a walking cast were elucidated by reviewing consecutive cases of a diabetic foot clinic. Study design: Retrospective observational study, chart review Material and methods: Cases with active-stage Charcot foot were considered, in whom written reports on baseline and follow-up MRI studies were available for assessment. Only cases without concomitant infection or skin ulcer were chosen, in whom both was documented, onset of symptomatic foot swelling and patient compliance with cast treatment. Results: From 1994 to 2017, 45 consecutive cases in 37 patients were retrieved, with 95 MRI follow-up studies (1–6 per case, average interval between studies 13 weeks). Decreasing EESC was documented in 66/95 (69%) follow-up studies. However, 29/95 (31%) studies revealed temporarily increasing, migrating or stagnating EESC. Conclusion: EESC on MRI disappear in response to prolonged offloading and immobilizing treatment; however, physiologic as well as pathologic fluctuations of posttraumatic EESC have to be considered when interpreting the MR images. Conventional MRI is useful for surveillance of active-stage Charcot foot recovery.

Systematic review of techniques to monitor remission of acute Charcot neuroarthropathy in people with diabetes

“…MRI as a monitoring tool for CN is increasingly acknowledged as a potentially more accurate method for monitoring and this is supported by the studies we included. 11,21,24 This warrants further…”

“…Some studies still rely on subjective measures of temperature difference between feet to monitor CN. 7,8,15,21,26,35 The first paper included in this review which used temperature measurement for monitoring in CN was published in 1997. 38 The authors report that the cut-off point of 4 F (2.2 C) for healing was not evidence-based but it appears to have been adopted as the standard for clinical decision making in subsequent studies and guidelines.…”

“…In the first group, the evaluation of monitoring techniques was the study's primary aim, so likely to report data to address the first four objectives on the efficacy and acceptability of the techniques. 11,[21][22][23][24][25]38 In the second group, the study's primary aim was to report outcomes of CN but they may also describe monitoring techniques used, thus providing data to answer our fifth objective on whether monitoring techniques influence outcomes. [6][7][8][9][10][12][13][14][15][16][26][27][28][29][30][31][32][33][34][35][36][37] 3.3 | Techniques used in the monitoring of CN Armstrong et al 38 Level 3…”

“…Wukich et al 37 Level 2 21 The third study compared bone marrow oedema on MRI at baseline and after 4 months, and correlated this to symptoms of CN in 13 participants. There was a statistically significant decrease in bone oedema over 4 months, with a statistically significant correlation between pain and soft tissue oedema and the bone marrow oedema over the same timescale.…”

A randomised feasibility study of serial magnetic resonance imaging to reduce treatment times in Charcot neuroarthropathy in people with diabetes (CADOM): a protocol

“…The use of MRI in monitoring CN therefore needs to be formally evaluated in a trial [30]. However, the evidence to support a full randomised controlled trial is presently insufficient.…”