Rates and timing of subsequent amputation after initial minor amputation

Risk Factors for Lower Extremity Minor Amputation Conversion to Major Amputation

OBJECTIVES

Minor lower extremity amputations have become an important part of the limb salvage approach but are not as benign as previously thought. This study investigates the difference in outcome between toe/ray versus midfoot amputations and the risk factors for major amputation conversion associated with each procedure.

METHODS

We performed retrospective chart review of foot amputation patients at a single tertiary care medical center with a primary end point of conversion to major amputation and secondary end points of one-year wound healing and mortality rate. We collected data on relevant medical comorbidities, non-invasive vascular imaging, revascularization, repeat amputations, wound healing rate, and one-year mortality. Patients were separated into toe/ray amputations versus midfoot amputation groups and compared using descriptive statistics, Chi Squared tests, Cox proportional hazards, and a multivariate logistic regression model.

RESULTS

A total of 375 amputations were included in the analysis. 65.3% (245 patients) included toe/ray amputations and 34.7% (130 patients) included midfoot amputations. We compared these two cohorts with regard to their rate of conversion to repeat minor and/or major amputation in addition to overall mortality. The toe/ray group underwent more repeat minor amputations within one year after index amputation (34.7% vs. 21.5%, p=0.008) and wound healing (epithelization) at 90 days was also higher in this group. The midfoot group had a higher conversion to major lower extremity amputation within one year on univariate analysis (20.8 vs. 6.9%, p<0.001). Overall one-year mortality was 6.17% and there was no significant difference between groups.

CONCLUSION

While there is a consistency with previous studies that found no significant overall difference in mortality between types of minor LEA, we have extended this previous work by demonstrating the independent risk factors for conversion to major amputation between types of minor LEA. Comparing these two groups will assist surgeons in choosing the appropriate level of amputations and will enhance patient's understanding of their chance of wound healing and risk of repeat amputation.

Comorbidity and risk factors of subsequent lower extremity amputation in patients diagnosed with diabetes in Saskatchewan, Canada

OBJECTIVE

Subsequent limb amputation (SLA) may be necessary due to disease progression, infection, or to aid prosthesis fit. SLA in Saskatchewan has increased 3.2% from 2006 to 2019 with minor SLA increasing 9.6% during that period. Diabetes affects a large proportion of patients who require SLA; however, the impact of additional comorbidities is not clear.

METHODS

First-episode subsequent lower extremity limb amputation (SLEA) cases with the presence/absence of diabetes, other comorbidities, and demographic characteristics from 2006-2019 were retrieved from Saskatchewan's Discharge Abstract Database. Logistic regression was performed to examine the magnitude of the odds of SLEA.

RESULTS

Among the 956 first-episode SLEA patients investigated, 78.8% were diagnosed with diabetes. Of these, 76.1% were male and 83.0% were aged 50 + years. Three comorbidities: renal failure (AOR = 1.9, 95% Cl 1.1 - 3.0), hypertension (AOR = 3.0, 95% Cl 2.0 - 4.5), and congestive heart failure (AOR = 2.0, 95% CI 1.2 - 3.2), conferred the highest odds of SLEA. The odds of SLEA is greatest for those aged 50-69 years, males, Registered Indians, and associated with a prolonged hospital stay.

DISCUSSION

These data are important as they may help medical providers identify patients at the highest risk of SLEA and target interventions to optimize outcomes.

Do Exercise Programs Improve Fitness, Mobility, and Functional Capacity in Adults With Lower Limb Amputation? A Systematic Review on the Type and Minimal Dose Needed

OBJECTIVE

To answer the following questions: (1) Do physical activity (PA) and exercise improve fitness, mobility, and functional capacity among adults with lower limb amputation (LLA) and (2) What is the type and minimum dose of PA (frequency, intensity and duration) needed?

DESIGN

Systematic review.

SETTING

Outpatient intervention, outside of the prosthetic rehabilitation phase.

PARTICIPANTS

Adults with lower limb amputation living in the community.

INTERVENTION

Any physical activity or exercise intervention.

OUTCOMES AND MEASURES

Any fitness, mobility, or functional capacity indicators and measurements.

RESULTS

Twenty-three studies were included, totaling 408 adults with LLA. Studies evaluated the effect of structured PA sessions on fitness, mobility, and functional capacity. The highest evidence is for mixed exercise programs, that is, programs combining aerobic exercise with strengthening or balance exercise. There is moderate confidence that 1-3 sessions of 20-60 minutes of exercise per week improves balance, walking speed, walking endurance, and transfer ability in adults with LLA above the ankle. As for flexibility, cardiorespiratory health, lower-limb muscles strength, and functional capacity, there was low confidence that exercise improves these fitness components because of the lack of studies.

CONCLUSION

Exercise 1-3 times per week may improve balance, walking speed, walking endurance, and transfer ability in adults with LLA, especially when combining aerobic exercises with lower limb strengthening or balance exercises. There is a need for most robust studies focusing on the effect of PA on cardiorespiratory health, muscles strength, flexibility, and functional status.

Outcomes after minor lower limb amputation for peripheral arterial disease and diabetes: population-based cohort study

BACKGROUND

Patients with diabetes and peripheral arterial disease are at increased risk of minor amputation. The aim of study was to assess the rate of re-amputations and death after an initial minor amputation, and to identify associated risk factors.

METHODS

Data on all patients aged 40 years and over with diabetes and/or peripheral arterial disease, who underwent minor amputation between January 2014 and December 2018, were extracted from Hospital Episode Statistics. Patients who had bilateral index procedures or an amputation in the 3 years before the study were excluded. Primary outcomes were ipsilateral major amputation and death after the index minor amputation. Secondary outcomes were ipsilateral minor re-amputations, and contralateral minor and major amputations.

RESULTS

In this study of 22 118 patients, 16 808 (76.0 per cent) were men and 18 473 (83.5 per cent) had diabetes. At 1 year after minor amputation, the estimated ipsilateral major amputation rate was 10.7 (95 per cent c.i. 10.3 to 11.1) per cent. Factors associated with a higher risk of ipsilateral major amputation included male sex, severe frailty, diagnosis of gangrene, emergency admission, foot amputation (compared with toe amputation), and previous or concurrent revascularization. The estimated mortality rate was 17.2 (16.7 to 17.7) per cent at 1 year and 49.4 (48.6 to 50.1) per cent at 5 years after minor amputation. Older age, severe frailty, comorbidity, gangrene, and emergency admission were associated with a significantly higher mortality risk.

CONCLUSION

Minor amputations were associated with a high risk of major amputation and death. One in 10 patients had an ipsilateral major amputation within the first year after minor amputation and half had died by 5 years.

Surgical Outcomes of Regional Versus General Anesthesia in 203 Patients with Upper- and Lower-Extremity Amputation: A Retrospective Study from a Single Center in Turkey

BACKGROUND This retrospective study from a single center in Turkey aimed to compare the surgical results of regional anesthesia and general anesthesia in 203 patients with upper- and lower-extremity amputations. MATERIAL AND METHODS The study population consisted of patients who underwent extremity amputation between 2017 and 2021. Patients' demographic data, comorbidities, American Society of Anesthesiology (ASA) scores, amputated extremities, causes and extents of amputations, length of hospital stay, associated mortality/morbidity, and postoperative 90-day mortality data were comparatively analyzed between the groups created according to the anesthesia methods used in amputations. RESULTS The study consisted of 203 patients, of whom 80.8% were male. The most commonly used anesthesia method was peripheral nerve blocks (32.5%), followed by spinal anesthesia (31.5%), general anesthesia (31.0%), epidural anesthesia (2.0%), combined spinal-epidural anesthesia (1.5%), and sedo-analgesia (1.5%). Of the amputations performed, 37.0% were upper-extremity and 63.0% were lower-extremity. Peripheral nerve blocks were used most frequently in upper-extremity amputations (71.5%), and spinal anesthesia was used most frequently in lower-extremity amputations (48.9%). The mean length of hospital stay of the patients who underwent surgery under regional anesthesia methods was shorter than that of those who underwent general anesthesia (8.7±7.4 days vs 15.0±20.6 days). The mortality rate was 0.5% in the first 24 h, 0.5% in the next 48 h, and 4.9% in total. CONCLUSIONS The study findings demonstrated that performing extremity amputations under regional anesthesia techniques, particularly peripheral nerve blocks, reduces mortality/morbidity, the need for postoperative intensive care, mean length of stay in hospital, and hospital costs.

What Went Wrong with VEGF-A in Peripheral Arterial Disease? A Systematic Review and Biological Insights on Future Therapeutics

BACKGROUND

Of the 200 million patients worldwide affected by peripheral arterial disease (PAD), 4% will inevitably require major limb amputation. Previous systematic reviews presented a conflicting body of evidence in terms of vascular endothelial growth factor (VEGF) family member effects upon PAD natural progression. Despite that, modulation of intrinsic angiogenesis mechanisms targeting the VEGF family members still confers an attractive therapeutic target. The aim of the present study was to evaluate current evidence of VEGF modulation in the context of PAD.

METHODS

This is a systematic literature review conducted according to the PRISMA guidelines and registered under PROSPERO database [CRD42021285988]. Independent literature search was performed up to April 1, 2022, on six databases. A total of 22 eligible studies were identified [N: 3, interventional patient studies; N: 19, animal studies]. Animal studies were appraised by the SYRCLE risk of bias tool, while human participant studies were assessed by the Newcastle Ottawa scale. Overall, quality of evidence was deemed fair for both animal and human studies. Main study outcomes were percentage change of injured vessel lumen stenosis and neointimal area formation upon VEGF modulation (inhibition or activation) in comparison with control group.

FINDINGS

Nineteen animal models and three human participant studies were included in the systematic review and assessed separately. Positive modulation of VEGF-A in animal models resulted in a median decrease of 65.58% [95% CI 45.2; 71.87] in lumen stenosis [14 studies]. Furthermore, positive modulation of VEGF-A was found to reduce neointimal area proliferation by a median decrease of 63.41% [95% CI 41.6; 79.59] [14 studies]. Median end of study duration was 28 days [range: 14-84 days]. Data were insufficient to assess these outcomes with respect to VEGF-B or VEGF-C modulation. The limited number of available human studies presented inadequate outcome assessment despite their overall fair NOS grading.

INTERPRETATION

VEGF-A-positive modulation decreases lumen stenosis and neointimal hyperplasia in PAD simulation animal models. Previously identified variability among outcomes was found to strongly stem from the variability of experimental designs. Clinical applicability and safety profile of VEGF-A in the context of PAD remain to be defined by a robust and uniformly designed body of further animal model-based experiments.

Prognostic Factor of Lower Limb Amputation among Diabetic Foot Ulcer Patients in North-East Peninsular Malaysia

Lower limb amputation (LLA) is a common complication of diabetic foot ulcer (DFU), which can lead to a higher 5-year mortality rate compared to all cancers combined. This study aimed to determine the prognostic factors of LLA among DFU patients in Kelantan from 2014 to 2018. A population-based study was conducted using secondary data obtained from the National Diabetic Registry (NDR). There were 362 cases that fulfilled the study criteria and were further analysed. The prognostic factors were determined by Multiple Cox Proportional Hazards Regression. There were 66 (18.2%) DFU patients who underwent LLA in this study, while 296 (81.8%) were censored. The results revealed that the factor leading to a higher risk of LLA was abnormal HDL-cholesterol levels (Adj. HR 2.18; 95% CI: 1.21, 3.92). Factors that led to a lower risk of LLA include DFU in patients aged 60 or more (Adj. HR 0.48; 95% CI: 0.27, 0.89) and obesity (Adj. HR 0.45; 95% CI: 0.22, 0.89). In conclusion, our model showed that abnormal HDL cholesterol was associated with a 2 times higher risk of LLA when adjusted for age and BMI. Any paradoxical phenomena should be addressed carefully to avoid wrong clinical decision making that can harm the patient.

Early ABI Testing May Decrease Risk of Amputation for Patients With Lower Extremity Ulcers

BACKGROUND

Patients with lower extremity wounds from diabetes mellitus or peripheral artery disease (PAD) have a risk of amputation as high as 25%. In patients with arterial disease, revascularization decreases the risk of amputation. We aimed to determine if the early assessment of arterial perfusion correlates with the risk of amputation.

METHODS

We retrospectively reviewed patients referred to the vascular clinic over 18 months with Rutherford Grade 5 and 6 chronic limb-threatening ischemia to determine if patients had a pulse exam done at the time the wound was identified and when ankle brachial index (ABI) testing to evaluate perfusion was performed. Kaplan Meier analysis was used to determine if the timing of ABI testing affected the time to revascularization, wound healing, and risk of amputation.

RESULTS

Ninety-three patients with lower extremity wounds were identified. Of these, 59 patients (63%) did not have a pulse exam performed by their primary care provider when the wound was identified. Patients were classified by when they underwent ankle brachial index testing to assess arterial perfusion. Twenty-four had early ABI (<30 days) testing, with the remaining 69 patients having late ABI testing. Patients in the early ABI group were more likely to have a pulse exam done by their PCP than those in the late group, 12 (50%) vs. 22 (32%), P = 0.03. Early ABI patients had a quicker time to vascular referral (13 days vs. 91 days, P < 0.001). Early ABI patients also had quicker times to wound healing than those in the late group (117 days vs. 287 days, P < 0.001). Finally, patients that underwent early ABI were less likely to require amputation (Fig. 1), although this did not reach statistical significance (P = 0.07).

CONCLUSIONS

Early ABI testing expedites specialty referral and time to revascularization. It can decrease the time to wound healing. Larger cohort studies are needed to determine the overall effect of early ABI testing to decrease amputation rates.

Lower extremity reamputation in people with diabetes: a systematic review and meta-analysis

In this study, we determined the reamputation-free survival to both limbs and to the contralateral limb only following an index amputation of any-level and assessed whether reamputation rates have changed over time. We completed a systematic search using PubMed and screened a total of 205 articles for data on reamputation rates. We reported qualitative characteristics of 56 studies that included data on reamputation rates and completed a meta-analysis on 22 of the studies which enrolled exclusively participants with diabetes. The random-effects meta-analysis fit a parametric survival distribution to the data for reamputations to both limbs and to the contralateral limb only. We assessed whether there was a temporal trend in the reamputation rate using the Mann-Kendall test. Incidence rates were high for reamputation to both limbs and to the contralateral limb only. At 1 year, the reamputation rate for all contralateral and ipsilateral reamputations was found to be 19% (IQR=5.1%-31.6%), and at 5 years, it was found to be 37.1% (IQR=27.0%-47.2%). The contralateral reamputation rate at 5 years was found to be 20.5% (IQR=13.3%-27.2%). We found no evidence of a trend in the reamputation rates over more than two decades of literature analyzed. The incidence of lower extremity reamputation is high among patients with diabetes who have undergone initial amputations secondary to diabetes, and rates of reamputation have not changed over at least two decades.

Perceptions of patients with wounds due to chronic limb-threatening ischemia

Patients with chronic limb-threatening ischemia (CLTI) face numerous barriers to caring for lower extremity wounds. We explored the perceptions of CLTI patients to their wound/management and sought to determine attitudes towards their vascular provider as well as willingness for management through telemedicine. Patients admitted to hospital for treatment of Rutherford Grade 5 and 6 CLTI were asked complete a wound evaluation survey and took part in a semi-structured interview. Semi-structured interviews were recorded, transcribed, and analyzed using an inductive coding strategy. Codes were grouped for thematic analysis and aggregated into assertions. Eleven patients with a mean age of 60 years (35-79 years) were interviewed. All patients had peripheral artery disease (PAD) and eight patients had diabetes as well. Three overarching themes were identified. First, patients appear to have limited coping mechanisms and are overwhelmed by the care of their wounds. Second, in this cohort of patients, many had become passive observers of their care as demonstrated by a limited understanding of their disease processes and detachment from wound management. The third theme was how strong the desire to do everything to prevent limb loss was, but patients acknowledged this is hard to translate into real life with limited resources. Patients with CLTI have concerns that vascular providers must recognize and address to build strong patient-provider relationships and increase activation for management of their wounds and other medical conditions. Patients who have access to technology and with guidance may be able to understand getting care through remote medicine.