"Treatment of Charcot Neuroarthropathy and Osteomyelitis of the Same Foot: A Retrospective Cohort Study."- A Brief Review

Martin Berli*, Lazaros Vlachopoulos, Sabra Leupi, Thomas Boeni, Charlotte Vlachopoulos-Baltin

Department of Orthopedicsn University Hospital Balgrist Zurich, Switzerland


A brief review of the above-mentioned article: forty patients with 43 affected feet and 60 cases of osteomyelitis were included in this study. They were split into two groups, one with osteomyelitis outside and another one with osteomyelitis within the active Charcot region. The results showed that the amputation rate did not differ between the two groups, although in group 1 – osteomyelitis outside the active Charcot region.

amputations were exclusively performed at the forefoot and in group 2 – with osteomyelitis within the active Charcot region – exclusively in the mid- and hindfoot. Amputations in group 2 were, therefore, more high level. The duration of immobilization and antibiotic treatment was significantly longer in group 2. We conclude, that patients treated for osteomyelitis in an active Charcot foot should be considered and treated as separate entities, depending on whether the osteomyelitis is located within or outside the active Charcot region. If osteomyelitis occurs outside the active Charcot region, primary amputation may be preferred to internal resection.


The Charcot – or neuroosteoarthropathic – foot is the final form of a neuropathic foot, which ends in severe deformity and bony destruction1-3. Since the most frequent cause of the neuropathy is long-term diabetes mellitus, it is often also called diabetic neuroosteoarthropathy (DNOAP)4, which is not entirely correct, as several other reasons for neuropathy exist, such as toxins (e.g. alcohol, chemotherapy), deficits of vitamin B12 or folic acid, etc. Neuroarthropathy of the foot was first described by Jean-Martin Charcot (1825-1893) a French neurologist, who worked at the Hôpital de la Pitié-Salpêtriére in Paris5.

The classic symptoms of the disease are redness, warmth and swelling, but – due to the neuropathy – lack of pain. Neuropathy is also the main reason why deformity may develop, as the patient continues to fully weight bear despite an increasing fragility of the bones. Underneath the aforementioned symptoms, the bones become osteopenic and fracture, which may lead to the final shape of the foot, the so-called rocker-bottom deformity. Due to the bony prominences, this shape of the foot is prone to ulcerations and infection. With the ulcerations, there is an increasing risk of infection and – if they are not treated quickly and appropriately – amputation.

Osteomyelitis is one of the main differential diagnoses of the Charcot foot. The central diagnostic tool during treatment of the Charcot foot is magnetic resonance imaging (MRI). It is very difficult to differentiate an active Charcot foot from osteomyelitis. The situation becomes even more difficult if one is dealing with an infected Charcot foot. For this reason, we decided to review our cases of infected Charcot feet, in order to find a pattern and possibly identify treatment recommendations to reduce the number of patients undergoing septicemia or amputation6,7.

Patients who were treated for Charcot foot and osteomyelitis between 2002 and 2012, were selected from our electronic hospital patient data collection. Inclusion criteria were: a diagnosis of Charcot neuroarthropathy (CN) according to the definition and diagnostic criteria of the French neurologist J.M. Charcot, radiographs of the affected foot, and osteomyelitis of the same foot, which was confirmed with radiological findings of osteomyelitis on MRI, positive bone biopsy cultures, and blood tests (i.e., C-reactive protein). Exclusion criteria were: primary treatment at another institution, or a previous fracture due to trauma of the same foot.

Table 1: Factors that potentially influence effects of cognitive stimulation in patients with dementia

 

ID Side Age Gender Sanders Osteomyelitis Osteomyelitis Location Antibiotic Treatment (days) Initial Surgical Treatment Immobilizatio n (days) Treatment Duration (days) Amputation
1 right 55.3 male 4 outside forefoot 41 amputation 41 44 Transmetatarsal
  right 56.0   4 outside forefoot 21 amputation 129 129 Toe
2 right 63.7 male 1 Charcot midfoot 60 limited resection 63 61  
3 left 84.8 female 1 Charcot forefoot 35 amputation 29 256 Transmetatarsal
4 left 65.1 male 3 outside forefoot 30 amputation 32 76 Toe
  left 68.1   3 outside forefoot 115 amputation 74 194 Toe
5 right 44.7   3 outside midfoot 122 none na 230  
6 right 77.3 female 2 Charcot midfoot 130 debridement na 100  
  right 78.8   2 Charcot midfoot 120 debridement na 245  
  right 79.2   2 Charcot midfoot 80 debridement na 80 Transtibial
7 left 44.5 male 4 Charcot hindfoot 107 arthodesis 83 124  
  left 45.7   4 Charcot hindfoot 134 arthodesis 101 57  
  left 48.5   4 outside forefoot 15 amputation 22 186 Toe
  right 46.8   4 outside forefoot 24 none na 50  
  right 47.8   4 Charcot hindfoot 35 arthodesis 120 143  
8 left 62.2 female 2 outside forefoot 70 limited resection 60 287  
9 left 46.6 male 2 outside forefoot 50 none 82 76  
10 left 51.0 male 4 Charcot hindfoot 152 amputation 389 512 Transtibial
11 right 42.9 male 3 Charcot hindfoot 118 debridement 290 97  
  right 46.1   3 Charcot hindfoot 75 arthodesis 195 917  
12 left 82.2 female 1 Charcot forefoot 67 limited resection 139 175  
13 left 63.3 male 2 Charcot midfoot 58 amputation 115 309 Lisfranc
14 left 46.9 male 2 Charcot midfoot 238 limited resection na 795 Transtibial
15 left 69.9 male 2 Charcot midfoot 57 limited resection 266 353  
16 right 57.9 male 1 Charcot forefoot 75 amputation 135 247 Toe
17 right 55.6 male 2 outside forefoot 34 amputation 43 56 Transtibial
18 right 71.3 male 4 outside forefoot 72 limited resection 20 99  
  right 73.0   4 outside forefoot 48 amputation 26 73 Toe
19 right 74.4 female 2 outside forefoot 37 amputation 19 204 Toe
20 right 60.3 male 2 Charcot midfoot 173 debridement 142 181  
21 left 51.4 female 1 Charcot forefoot 24 limited resection na 51  
  left 53.1   1 Charcot forefoot 57 amputation na 850 Toe
  left 56.3   1 Charcot forefoot 49 amputation na 1070 Toe
22 left 56.0 male 2 Charcot forefoot 147 limited resection 144 231  
  left 56.1 male 2 outside forefoot 181 limited resection 48 78  
23 right 73.8 male 1 Charcot forefoot 49 arthodesis 99 803  
24 left 46.1 male 2 Charcot midfoot 78 debridement 68 85 Chopart
25 right 69.2 male 2 Charcot midfoot 121 limited resection 104 1320  
  right 75.4   2 outside forefoot 9 amputation 63 85 Toe
26 left 63.5 male 2 outside forefoot   amputation 39 120 Toe
  left 65.8   2 outside forefoot 51 amputation 87 87 Transmetatarsal
  right 68.5   2 Charcot midfoot 74 limited resection 286 132  
27 right 40.1 male 2 outside forefoot 40 limited resection 57 109  
  right 40.6   2 outside forefoot 40 limited resection 60 1128  
28 left 77.5 male 2 outside forefoot 52 limited resection na 62  
  left 78.5   2 outside forefoot 59 amputation na 116 Toe
29 right 61.1 male 2 outside forefoot 28 amputation 37 1315 Toe
30 left 61.5 female 1 Charcot forefoot 45 limited resection 17 58  
31 right 58.1 female 3 Charcot hindfoot 90 arthodesis 131 1147 Transtibial
32 left 52.6 male 2 outside forefoot 48 limited resection 177 491 Transtibial
33 right 61.3 male 5 Charcot hindfoot 23 amputation 181 216 Transtibial
34 right 64.3 male 2 Charcot midfoot 6 amputation 82 212 Transtibial
  left 67.0   2 outside forefoot 228 limited resection 228 69  
35 left 71.4 male 3 Charcot midfoot 45 limited resection na 245  
36 right 66.1 male 2 outside forefoot 37 amputation 304 304 Toe
37 left 45.9 male 2 outside forefoot 59 limited resection 150 721  
38 right 87.5 female 3 outside forefoot 26 limited resection 96 205 Transfemoral
30 left 54.1 female 3 outside forefoot 19 amputation na 61 Toe
  left 54.6   3 outside forefoot 33 amputation 101 137 Transmetatarsal
40 left 80.9 female 2 outside forefoot 27 amputation na 48 Toe

This study included 40 patients with 43 affected feet and a total of 60 cases of osteomyelitis. According to the localization of the osteomyelitis, the cases were divided into two groups: group 1 with osteomyelitis outside the active Charcot region, and group 2 with osteomyelitis within the active Charcot region. Each group consisted of 30 cases: group 1 (osteomyelitis outside the active Charcot region) included 22 patients with 23 affected feet; group 2 (osteomyelitis within the active Charcot region) included 23 patients with 24 affected feet; 5 patients had both, episodes of osteomyelitis outside and within the active Charcot region.

Logistic regression analysis was performed to address clustering of cases within patients, with amputation as the dependent variable and localization of osteomyelitis as the independent variable. Durations of antibiotic therapy and immobilization were calculated in days and analyzed as logarithmic transformed dependent variables in linear regression with robust standard error (i.e., patient identification as a cluster).

We demonstrated that patients in group 2 (osteomyelitis within the active Charcot region) had a longer duration of antibiotic treatment, with a mean of 84.1 ± 51.2 (range 6-236) days8,9. In contrast, group 1 (osteomyelitis outside the active Charcot region) was treated with antibiotics for a mean of 55.7 ± 48.9 (range 9-228) days (Table 1) (p = 0.045).

The duration of immobilization, which was achieved with a total contact cast10 was also extended in group 2 (mean 144 ± 91.8, range 17-389 days) compared to group 1 (mean 83.1 ± 70.5, range 19-304 days; p = 0.01).

The overall amputation rate was statistically similar for both groups (p = 0.09), with 19 amputations (63%) in group 1 (osteomyelitis outside the Charcot region) and 12 amputations (40%) in group 2 (osteomyelitis within the Charcot region). However, patients in group 2 underwent significantly more high level amputations compared to patients in group 1 (p = 0.009). A major amputation (above the ankle) was performed in 6/30 (20%) cases in group 2 and in 3/30 (10%) cases in group 1.

Significant differences in the amputation level (p<0.001), duration of antibiotic treatment (p=0.045), and duration of immobilization (p =0.01) were observed between the groups, which presented with osteomyelitis within the Charcot region versus outside the Charcot region. In the group with osteomyelitis outside the active Charcot region, the elimination of infection amputation could be achieved more quickly, since the affected area could be clearly defined. However, when osteomyelitis is localized within the active Charcot area, it is more difficult to correctly define the borders of the osteomyelitis, due to the bone edema caused by the Charcot disease, which may lead to the risk of too much bone being resected. For this reason, an extended duration of immobilization combined with antibiotic therapy is considered the treatment of choice if the osteomyelitis is located within the active Charcot zone.

The infection was considered to be cleared when inflammatory markers (i.e., C-reactive protein), MRI, and the clinical appearance of the foot, were all within normal parameters again. This was also confirmed with regular follow-up visits, to allow for immediate intervention in case of a reappearance of inflammation or signs of infection.

We concluded that patients treated for osteomyelitis in an active Charcot foot should be considered as separate entities when considering treatment protocols and in future research evaluating outcomes, depending on whether the osteomyelitis is located within or outside the active Charcot region. If osteomyelitis occurs outside the active Charcot region, primary amputation may be preferred to internal resection. Additional research in the form of prospective studies would be beneficial to compare the outcomes of internal resection versus amputation when osteomyelitis occurs outside the active Charcot region.

  1. Wukich DK, Sung W. Charcot arthropathy of the foot and ankle: modern concepts and management review. J Diabetes Complications. 2009; 23(6): 409-426.
  2. Rogers LC, Frykberg RG, Armstrong DG, et al. The Charcot foot in diabetes. Diabetes Care. 2011; 34(9): 2123-2129.
  3. Frykberg RG, Bevilacqua NJ, Habershaw G. Surgical off-loading of the diabetic foot. J Vasc Surg. 2010; 52(3 Suppl): 44S-58S.
  4. Sanders LJ FR. Diabetic neuropathic osteoarthropathy: the Charcot foot. In The high risk foot in diabetes mellitus. 1991; 325-333.
  5. Charcot J. Lectures on the diseases of the nervous system delivered at la Salpêtrière. HC Lea. 1879.
  6. Wukich DK, Hobizal KB, Sambenedetto TL, et al. Outcomes of Osteomyelitis in Patients Hospitalized With Diabetic Foot Infections. Foot Ankle Int. 2016; 37(12): 1285-1291.
  7. Gazis A, Pound N, Macfarlane R, et al. Mortality in patients with diabetic neuropathic osteoarthropathy (Charcot foot). Diabet Med. 2004; 21(11): 1243-1246.
  8. Zeun P, Gooday C, Nunney I, et al. Predictors of Outcomes in Diabetic Foot Osteomyelitis Treated Initially With Conservative (Nonsurgical) Medical Management A Retrospective Study. Int J Low Extrem Wounds. 2016; 15(1): 19-25.
  9. Lesens O, Desbiez F, Theis C, et al. Working Group on Diabetic O: Staphylococcus aureus-Related Diabetic Osteomyelitis: Medical or Surgical Management A French and Spanish Retrospective Cohort. Int J Low Extrem Wounds. 2015; 14(3): 284-290.
  10. Armstrong DG, Lavery LA, Wu S, et al. Evaluation of removable and irremovable cast walkers in the healing of diabetic foot wounds: a randomized controlled trial. Diabetes Care. 2005; 28(3): 551-554.
 

Article Info

  • Journal of Neurology & Neuromedicine
  • Article Type : Review Article
  • View/Download pdf
  • DOI : 10.29245/2572.942X/2018/4.1176

Article Notes

  • Published on: August 16, 2018

Keywords

  • Charcot Foot

  • Neuroarthropathy
  • Diabetic Foot
  • Amputation
  • Osteomyelitis

*Correspondence:

Dr. Martin Berli, MD
Deputy team leader Technical Orthopedics, Department of Orthopedics, University Hospital Balgrist, Forchstr. 340, 8008 Zurich, Switzerland
Telephone No: 044 386 57 58; Fax No: 044 386 30 09
Email: martin.berli@balgrist.ch.
Copyright: ©2018 Berli M. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License.
Citation: Berli M, Vlachopoulos L, Leupi S, Boeni T, Baltin CV. “Treatment of Charcot Neuroarthropathy and Osteomyelitis of the Same Foot: A Retrospective Cohort Study.” – A Brief Review. J Neurol Neuromed (2018) 3(4):97-100