Lower Extremity Amputation and Mortality Rates in the Reconstructed Diabetic Charcot Foot and Ankle With External Fixation: Data Analysis of 116 Patients

Minor and Major Amputation Rates Following Midfoot Charcot Reconstructive Surgery

Charcot neuroarthropathy (CNA) is a progressive disease that affects the bones and joints of the foot. To prevent collapse and loss of stability within the pedal architecture, CNA should be diagnosed and managed early. The objective of this retrospective study was to review patients who underwent midfoot CNA reconstructive surgery and evaluate subsequent rates of minor and major amputations. Secondary objectives include identifying patients that underwent midfoot CAN with and without a subtalar joint (STJ) arthrodesis. Out of the 72 patients, 4 (5.6%) underwent minor (digital, ray) amputation, 2 (2.8%) underwent proximal amputations (either below or above the knee), and none underwent midfoot amputation (transmetatarsal, Lisfranc, Chopart). A Fisher's exact test was employed to compare the outcomes of minor and major amputation rates in our CNA cohort with those who underwent midfoot CNA reconstruction with STJ arthrodesis and found no statistical significance (p = .15). Overall, a total progression to amputation was 8.4% following midfoot CNA reconstruction, with 2.8% of patients undergoing major amputation (below knee or above knee). Despite no statistical significance, we recommend surgeons to consider including an STJ arthrodesis in addition to midfoot CNA reconstruction to establish a stable and plantigrade foot.

Amputation and mortality frequencies associated with diabetic Charcot foot arthropathy: a meta-analysis

BACKGROUND

Five-year mortality and amputation frequencies after new-onset diabetic ulceration have been reported up to 55% and 74%, respectively. for patients with lower-extremity amputation. Following Charcot arthropathy, these frequencies were reported with wide variations. The aim of this meta-analysis is to provide a quantitative evaluation of amputation and mortality frequencies in a diabetic patient with a Charcot foot arthropathy.

METHODS

Electronic search strategy was applied on Medline, Web of Science, Cochrane Library and Google Scholar since inception to December 2021. Extracted data included study design, sample and patients characteristics, diabetes type and duration, lab results, ulcers at diagnosis, co-morbidities and follow up period. Meta-analysis reporting random-effects values was used to generate the weights results.

RESULTS

A total of 16 studies were included in the quantitative meta-analysis with a pooled sample of 2250 patients with 2272 Charcot feet. Two studies including 255 patients yielded a 1-year mortality frequency of 4% (95% CI = 0.018-0.065). Seven studies including 1706 patients reported a 5-year mortality frequency of 24.5% (95% CI = 0.172-0.326, I² = 88.5%). Four studies including 277 patients yielded a seven plus year mortality frequency of 16% (95% CI = 0.065-0.289, I² = 84.3%). Ten studies including 871 foot yielded an amputation frequency of 15% (95% CI = 0.067-0.258, I² = 93.6%) where 9% where major amputations (95% CI = 0.062-0.127, I² = 60%) and 5% were minor amputations (95% CI = 0.004-0.126, I² = 94.7%) CONCLUSION: Diabetic Charcot arthropathy yields marked risk of amputation and mortality. However, mortality frequencies were unexpectedly lesser compared to those related to the published frequencies associated with diabetic foot ulcers.

Success and Survivorship Following Charcot Reconstruction: A Review of 151 Cases

Charcot neuroarthropathy is a debilitating condition that frequently leads to skeletal deformity and pedal ulceration in the insensate foot. Results are often poor and no clear guidelines for surgical management exist. Additionally, amputation rates vary widely making it difficult to accurately inform patients of risks. Few studies have assessed outcomes to identify patients for whom reconstruction is likely to fail. The literature is limited, with small sample sizes and mortality infrequently addressed. We performed a retrospective observational study of patients with Charcot neuroarthropathy to assess overall amputation and mortality rates at 30 days, 1 year, and 3 years postreconstruction and evaluated associated risk factors. Rates of infection, re-ulceration, and return to walking were also assessed. We identified 151 patients over a 5-year period. Demographic and clinical characteristics were collected. Descriptive statistics, Cox proportional hazard model, and logistic regression were used. Overall, 22 (14.6%) patients died, and 23 (15.2%) patients advanced to limb amputation postoperatively. End-stage renal disease, peripheral vascular disease, reconstruction during active phase Charcot process, and reconstruction at the ankle or subtalar joint were all associated with poor outcomes. The risk of mortality was 2.5 times higher in patients with end-stage renal disease, and 3.4 times higher among patients with peripheral vascular disease. Patients with ankle or subtalar joint reconstruction were 70% less likely to return to walking compared to medial column reconstruction. Due to these findings, we suggest that patients with such comorbidities be advised of increased risk for complications including failure to return to walking, amputation, and death.

Long-term outcome of persons with diabetic and non-diabetic neuro-osteoarthropathy after foot correction using external fixation

AIM

Diabetic neuro-osteoarthropathy (Charcot foot) is a serious form of diabetic foot syndrome, often leading to severe deformity of the foot and subsequently to ulcers and osteomyelitis. The aim of this retrospective study was to determine the success rate and long-term outcomes for a Charcot foot operation using external fixation in 115 individuals who underwent surgery between July 2008 and December 2012.

METHODS

Some 115 consecutive persons, 78 (68%) men and 37 (32%) women, were enrolled in this study. The eligibility criterion for this retrospective study was reconstructive foot surgery using a Hoffmann II external fixator in diabetic and non-diabetic neuro-osteoarthropathy. The main examination parameters in the follow-up were walking ability, amputation and mortality. Average follow-up was 5.7 (± 3.2) years.

RESULTS

Ninety-seven per cent of people were able to walk after the operation with bespoke shoes or an orthosis. At follow-up, 77% were able to walk and 51% were fully mobile even outside the home. Subsequent amputations were performed in 29 individuals (26%), with 17 (15%) minor and 12 (11%) major amputations. Forty-seven individuals died before follow-up, the majority (53%) from cardiovascular events. Average survival time post surgery was 4.5 (± 2.9) years.

CONCLUSION

Reconstruction surgery using external fixation is a very useful method for maintaining walking ability in the case of conservatively non-treatable diabetic and non-diabetic neuro-osteoarthropathy. Individuals with severe Charcot foot disease had a low rate of major amputations. Osteomyelitis was the main reason for major amputations.

Is Reconstruction of Unstable Midfoot Charcot Neuroarthropathy Cost Effective from a US Payer's Perspective?

BACKGROUND

Charcot neuroarthropathy is a morbid and expensive complication of diabetes that can lead to lower extremity amputation. Current treatment of unstable midfoot deformity includes lifetime limb bracing, primary transtibial amputation, or surgical reconstruction of the deformity. In the absence of a widely adopted treatment algorithm, the decision to pursue more costly attempts at reconstruction in the United States continues to be driven by surgeon preference.

QUESTIONS/PURPOSES

To examine the cost effectiveness (defined by lifetime costs, quality-adjusted life-years [QALYs] and incremental cost-effectiveness ratio [ICER]) of surgical reconstruction and its alternatives (primary transtibial amputation and lifetime bracing) for adults with diabetes and unstable midfoot Charcot neuroarthropathy using previously published cost data.

METHODS

A Markov model was used to compare Charcot reconstruction and its alternatives in three progressively worsening clinical scenarios: no foot ulcer, uncomplicated (or uninfected) ulcer, and infected ulcer. Our base case scenario was a 50-year-old adult with diabetes and unstable midfoot deformity. Patients were placed into health states based on their disease stage. Transitions between health states occurred annually using probabilities estimated from the evidence obtained after systematic review. The time horizon was 50 cycles. Data regarding costs were obtained from a systematic review. Costs were converted to 2019 USD using the Consumer Price Index. The primary outcomes included the long-term costs and QALYs, which were combined to form ICERs. Willingness-to-pay was set at USD 100,000/QALY. Multiple sensitivity analyses and probabilistic analyses were performed to measure model uncertainty.

RESULTS

The most effective strategy for patients without foot ulcers was Charcot reconstruction, which resulted in an additional 1.63 QALYs gained and an ICER of USD 14,340 per QALY gained compared with lifetime bracing. Reconstruction was also the most effective strategy for patients with uninfected foot ulcers, resulting in an additional 1.04 QALYs gained, and an ICER of USD 26,220 per QALY gained compared with bracing. On the other hand, bracing was cost effective in all scenarios and was the only cost-effective strategy for patents with infected foot ulcers; it resulted in 6.32 QALYs gained and an ICER of USD 15,010 per QALY gained compared with transtibial amputation. As unstable midfoot Charcot neuroarthropathy progressed to deep infection, reconstruction lost its value (ICER USD 193,240 per QALY gained) compared with bracing. This was driven by the increasing costs associated with staged surgeries, combined with a higher frequency of complications and shorter patient life expectancies in the infected ulcer cohort. The findings in the no ulcer and uncomplicated ulcer cohorts were both unchanged after multiple sensitivity analyses; however, threshold effects were identified in the infected ulcer cohort during the sensitivity analysis. When the cost of surgery dropped below USD 40,000 or the frequency of postoperative complications dropped below 50%, surgical reconstruction became cost effective.

CONCLUSIONS

Surgeons aiming to offer both clinically effective and cost-effective care would do well to discuss surgical reconstruction early with patients who have unstable midfoot Charcot neuroarthropathy, and they should favor lifetime bracing only after deep infection develops. Future clinical studies should focus on methods of minimizing surgical complications and/or reducing operative costs in patients with infected foot ulcers.

LEVEL OF EVIDENCE

Level II, economic and decision analysis.

Surgical treatment of midfoot Charcot neuroarthropathy with osteomyelitis in patients with diabetes: a systematic review

OBJECTIVE

A wide range of clinical presentations of Charcot neuroarthropathy of the foot with concomitant osteomyelitis in patients with diabetes has been described. Existing literature provides an equally diverse list of treatment options. The purpose of this systematic review was to assess the outcomes specifically for the surgical management of midfoot Charcot neuroarthropathy with osteomyelitis in patients with diabetes.

METHOD

A systematic review was conducted by three independent reviewers using the following databases and search engines: Cumulative Index of Nursing and Allied Health Literature (CINAHL), Cochrane Library, EMBASE (Excerpta Medica dataBASE), Google Scholar, Ovid, PubMed and Scopus. Search terms used were: Charcot neuroarthropathy, osteoarthropathy, neuro-osteoarthropathy, neurogenic arthropathy, osteomyelitis, midfoot, foot, ankle, diabetes mellitus, ulceration, wound, infection, surgical offloading, diabetic reconstruction, internal fixation, external fixation. Studies meeting the following criteria were included: English language studies, studies published from 1997-2017, patients with diabetes mellitus surgically treated for Charcot neuroarthropathy of the midfoot (specified location) with concomitant osteomyelitis, with or without internal and/or external fixation, follow-up period of six months or more postoperatively, documentation of healing rates, complications, and need for revisional surgery. Studies which were entirely literature reviews, descriptions of surgical-only technique and/or cadaveric studies, patients without diabetes, studies that did not specify location of osteomyelitis and Charcot neuroarthropathy, and treatment proximal to and including Chopart's/midtarsal joint specifically talonavicular, calcaneocuboid, subtalar, ankle were excluded.

RESULTS

A total of 13 selected studies, with a total of 114 patients with diabetes of which 56 had surgical treatment for midfoot Charcot neuroarthropathy with osteomyelitis, met the above inclusion criteria and were used for data extraction.

CONCLUSION

Surgical intervention for midfoot Charcot neuroarthropathy with osteomyelitis in patients with diabetes demonstrated a relatively high success rate for a range of procedures including debridement with simple exostectomy, arthrodesis with or without internal or external fixation, and advanced soft tissue reconstruction. However, this systematic review emphasises the need for larger, better designed studies to investigate the efficacy and failure rates of surgical treatment in this group of patients.

Prognostic Scoring System for Patients Undergoing Reconstructive Foot and Ankle Surgery for Charcot Neuroarthropathy: The Charcot Reconstruction Preoperative Prognostic Score

Charcot neuroarthropathy is a destructive process that occurs in patients with peripheral neuropathy, often due to poorly controlled diabetes mellitus. Surgical reconstruction can be necessary to provide a plantigrade foot that is wound free. A risk of major amputation exists after a Charcot event and after attempted reconstruction. We retrospectively reviewed the data from 34 patients (36 reconstructions) who had undergone reconstructive surgery for Charcot neuroarthropathy. The mean patient age was 56.44 years. The mean follow-up period was 56 months. We collected patient age, body mass index, presence of wound or osteomyelitis, anatomic location, activity of disease, and hemoglobin A1c. Using these data, each patient was given a score using our novel prognostic scoring system, the Charcot Reconstruction Preoperative Prognostic Score (CRPPS). Our primary outcome measure was no wound and no major amputation at the final follow-up visit. The limb salvage rate was 89% (32 of 36), and 78% (28 of 36) had no wound at the final follow-up examination. For patients without a wound or major amputation at the final follow-up visit, the mean CRPPS was 2.96 ± 1.23. The mean CRPPS for those with a wound or major amputation at the final follow-up visit was 4.33 ± 1.07 (p = .0024). Univariate logistic regression revealed 2 statistically significant predictors of wound and/or amputation: anatomic location (odds ratio [OR] 5.0, 95% confidence interval [CI] 1.051 to 23.789; p = .043) and CRPPS (OR 2.724, 95% CI 1.274 to 5.823, p = .01). A CRPPS of ≥4 was also predictive of a negative outcome (OR 7.286, 95% CI 1.508 to 35.211; p = .013). This scoring system, with a sensitivity of 75%, specificity of 71%, and negative predictive value of 85%, is a potential starting point when educating patients and making treatment decisions in this exceptionally challenging group.

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.

Management of Osteomyelitis and Bone Loss in the Diabetic Charcot Foot and Ankle

Bone loss and destruction due to diabetic Charcot neuroarthropathy (CN) and osteomyelitis of the foot and ankle is a challenging clinical condition when lower extremity preservation is considered. Resection and excision of osteomyelitis and associated nonviable soft tissue can lead into large osseous and soft tissue defects that will most likely need the utilization of bone grafting and subsequent arthrodesis for stability and anatomic alignment. In the diabetic population with peripheral neuropathy, osseous instability can lead to subsequent lower extremity deformity, ulceration, infection and/or amputation. This article reviews the surgical approach in the presence of diabetic CN and concomitant osteomyelitis.

Comparison of Diabetic Charcot Patients With and Without Foot Wounds

BACKGROUND

The primary aim of this study was to evaluate the outcomes of a series of patients with Charcot neuroarthropathy (CN) who were evaluated in a tertiary care setting. We hypothesized that those patients with CN who presented with a Charcot-related foot wound would have lower rates of successful limb salvage than patients who presented without a wound.

METHODS

Two hundred forty-five patients (280 feet) were identified with diabetic CN during the time period from January 1, 2005, to June 1, 2015. This consecutive cohort of patients was treated by a single surgeon and had a mean age of 57.9 ± 10.0 years. Our CN patients were divided into 2 groups for the purpose of our analysis. Our study group included those patients who presented to our clinic with a Charcot-related foot wound. Our control group was composed of CN patients who presented without a Charcot-related foot wound.

RESULTS

Overall, 78 feet (27.9%) were successfully treated nonoperatively and 202 feet (72.1%) required some type of surgery. Of the 202 feet that received surgery, 22 (10.9%) were not felt to be suitable for reconstruction and underwent a definitive transtibial amputation without an attempt at reconstruction. An additional 18 patients underwent soft tissue surgery, which included drainage of infection, posterior muscle group lengthening, or soft tissue reconstructive flap surgery. The remaining 162 feet underwent osseous surgery, which included ostectomies for osteomyelitis, exostectomies, osteotomies, and arthrodesis. Eighteen of the 180 limbs (10.0%) that underwent soft tissue or osseous reconstruction ultimately required a transtibial amputation, resulting in a successful limb salvage rate of 90.0%. Thirty-five amputations were performed in 164 feet (21.3%) with Charcot-related foot wounds compared with 5 amputations in 116 feet (4.5%) without Charcot-related foot wounds (OR 6.02, 95% CI 2.28-15.91, P < .0001).

CONCLUSION

The presence of a Charcot-related foot wound at presentation increased the likelihood of a major lower extremity amputation by a factor of 6. Other risk factors that were associated with major amputation in patients included active infection at presentation, nonunion/instability after reconstruction, and a postoperative wound problem. The overall rate of successful limb salvage in patients deemed reconstructive candidates was 90%.

LEVEL OF CLINICAL EVIDENCE

Level III, retrospective, case-control study.

The Diabetic Charcot Foot from 1936 to 2016: Eighty Years Later and Still Growing

Knowledge of diabetic Charcot neuroarthropathy (DCN) has grown tremendously since this condition was first described in 1936 by William Riely Jordan. Despite advancements in diagnostic approaches and treatment options making DCN limb salvage a more viable option, ongoing and additional research is needed to determine the definitive pathogenesis, which may aid in prevention of the condition. This article chronicles the main developments for the study and management of DCN since 1936 and recommends using the term diabetic Charcot-Jordan foot when specifically managing foot and ankle neuroarthropathy joints in patients with diabetic neuropathy.