Negative-Pressure Wound Therapy and Diabetic Foot Amputations
A Retrospective Study of Payer Claims Data
Background: This study was undertaken to assess the benefits of negative-pressure wound therapy (NPWT) versus traditional wound therapies in reducing the incidence of lower-extremity amputations in patients with diabetic foot ulcers.
Methods: Administrative claims data for patients with diabetic foot ulcers from commercial payers (n = 3,524) and Medicare (n = 12,795) were retrospectively analyzed. Patients were divided into NPWT and control/traditional therapy groups on the basis of administrative codes. Risk-adjustment procedures were then performed to match patient risk categories (through total treatment costs) and wound severities (through debridement depth).
Results: The incidence of amputations in the NPWT groups was lower than that in the control groups. For the cost-based risk-adjustment analysis, amputation incidences with NPWT versus traditional therapy were 35% lower in the Medicare sample (10.8% versus 16.6%; P = .0077) and 34% lower in the commercial payer sample (14.1% versus 21.4%; P = .0951). Whereas overall amputation rates increased progressively with increasing wound debridement depth in both control groups, the same increasing trend did not occur in the NPWT groups.
Conclusions: Patients with diabetic foot ulcers in the Medicare sample treated with NPWT had a lower incidence of amputations than those undergoing traditional wound therapy; this finding was evident in wounds of varying depth in both populations studied. (J Am Podiatr Med Assoc 97(5): 351–359, 2007)
The Fitting of Amputated and Nonamputated Diabetic Feet
A French Experience at the Villiers-Saint-Denis Hospital
The Villiers-Saint-Denis Hospital in France specializes in the rehabilitation of and fitting of orthoses for lower-limb amputees, who frequently have diabetes mellitus. The percentage of partial-foot amputations has increased relative to the percentage of transtibial or transfemoral amputations. This article describes a complete range of orthoses and prostheses, adapted to each patient, that allow recovery of the standing position, gait ability, and physical activity. (J Am Podiatr Med Assoc 93(3): 221-228, 2003)
Transtibial (TTA) and transfemoral (TFA) amputations are rarely considered as distinct events when examining major lower-limb amputation outcomes. The objective of this study was to investigate the relationships among type 2 diabetes, diabetes management strategies, hemoglobin A1c levels, and other health factors related to TTA and TFA.
The retrospective medical record review included abstracting demographic and health-related data from the electronic medical records of 92 patients who received amputation-related services in a Department of Veterans Affairs hospital.
Patients who controlled their diabetes with insulin (with or without other oral agents) were significantly more likely to undergo TTA (adjusted odds ratio [aOR] = 7.63; 95% confidence interval [CI], 1.17–49.97; P = .03) compared with patients who controlled their diabetes through noninsulin medications or by diet. Patients who underwent no previous surgery (aOR = 6.66; 95% CI, 0.89-49.72; P = .06) or partial amputation only (aOR = 15.44; 95% CI, 1.04–228.29; P = .05) compared with a combination of partial amputation and bypass, thrombolectomy, or stent procedures were marginally to statistically significantly more likely to undergo TTA than TFA.
The preferential association between TTA with insulin-dependent diabetes and higher hemoglobin A1c levels versus TFA with previous lower-limb bypasses, stent placement, and thrombolytic interventions distinguishes TTA and TFA as two distinct entities, and awareness of this difference may help clinicians design preventive strategies accordingly.
Toe amputation is the most common partial foot amputation. Controversy exists regarding whether to primarily close toe amputations or to leave them open for secondary healing. The purpose of this study was to evaluate the results of closed toe amputations in diabetic patients, with respect to wound healing, complications, and the need for further higher level amputation.
We retrospectively reviewed the results of 40 elective or semi-elective toe amputations with primary closure performed in 35 patients treated in a specialized diabetic foot unit. Patients with abscesses or necrotizing fasciitis were treated emergently and were excluded. Patients in whom clean margins could not be achieved due to extensive cellulitis or tenosynovitis and patients requiring vascular intervention were excluded as well. Outcome endpoints included wound healing at 3 weeks, delayed wound healing, or subsequent higher level amputation.
Out of 40 amputations, 38 healed well. Thirty amputations healed by the time of stitch removal at 3 weeks and eight had delayed healing. In two patients the wounds did not heal and subsequent higher level amputation was eventually required.
In carefully selected diabetic foot patients, primary closure of toe amputations is a safe surgical option. We do not recommend primary closure when infection control is not achieved or in patients requiring vascular reconstruction. Careful patient selection, skillful assessment of debridement margins and meticulous technique are required and may be offered by experienced designated surgeons in a specialized diabetic foot unit.
Partial foot amputations (PFAs) are often indicated for the treatment of severe infection, osteomyelitis, and critical limb ischemia, which consequently leads to irreversible necrosis. Many patients who undergo PFAs have concomitant comorbidities and generally present with a severe acute manifestation of the condition, such as gangrenous changes, systemic infection, or debilitating pain, which would then require emergency amputation on an inpatient basis.
The purpose of this study was to track the recent prevalence of PFAs and to investigate the current demographic trends of the physicians managing and performing PFAs, specifically regarding medical degree and specialty. Doctors of podiatric medicine are striving to achieve parity with their allopathic and osteopathic surgical counterparts and become a more prominent part of the multidisciplinary approach to limb salvage and emergency surgical treatment. This study evaluated 4 years (2009–2012) of PFA data from the Pennsylvania state inpatient database in the two most populated areas of Pennsylvania: Philadelphia and Allegheny counties. Statistics on medical schools were obtained directly from the accrediting bodies of allopathic, osteopathic, and podiatric medical schools. The goal of this study was to evaluate the general trends of patients undergoing a PFA and to quantify the upswing of podiatric surgeons intervening in the surgical care of these patients.
The number of partial foot amputations in the United States rose from 2006 to 2012. Podiatric surgeons performed 46% of theses procedures for residents of Philadelphia County from 2009 to 2012. In Allegheny County podiatric physicians performed 42% of these procedures during the same time frame.
Partial foot amputations are increasing over time. Podiatric Surgeons perform a significant share of these operations. This share is increasing in the most populated areas of Pennsylvania.
Background: Prediction of amputation would aid clinicians in the management of diabetic foot infections. We aimed to assess the predictive value of baseline and post-treatment levels of acute phase reactants in the outcome of patients with diabetic foot infections.
Methods: We collected data prospectively during minimum follow-up of 6 months in patients with infected diabetic foot ulcers hospitalized in Dokuz Eylul University Hospital between January 1, 2003, and January 1, 2008. After excluding patients who did not attend the hospital for follow-up visits regularly (n = 36), we analyzed data from 165 foot ulcer episodes.
Results: Limb ischemia and osteomyelitis were much more frequent in patients who underwent amputation. Wagner grade, which assesses ulcer depth and the presence of osteomyelitis or gangrene, was higher in patients who needed amputation. Ulcer size was slightly larger in the amputation group. Baseline and post-treatment C-reactive protein levels, erythrocyte sedimentation rates, white blood cell counts, and platelet counts were significantly elevated in patients who underwent amputation. Albumin levels were significantly suppressed in the amputation group. Univariate analysis showed that a 1-SD increase in baseline and post-treatment C-reactive protein levels, erythrocyte sedimentation rates, and white blood cell counts and a 1-SD decrease in post-treatment albumin levels were significantly associated with increased risk of amputation. Post-treatment C-reactive protein level was strongly associated with amputation risk.
Conclusions: Circulating levels of acute phase reactants were associated with amputation risk in diabetic foot infections. (J Am Podiatr Med Assoc 101(1): 1–6, 2011)
In this study, we aimed to evaluate the potential use of a 3-phase bone scintigraphy method to determine the level of amputation on treatment cost, morbidity and mortality, reamputation rates, and the duration of hospitalization in diabetic foot.
Thirty patients who were admitted to our clinic between September 2008 and July 2009, with diabetic foot were included. All patients were evaluated according to age, gender, diabetes duration, 3-phase bone scintigraphy, Doppler ultrasound, amputation/reamputation levels, and hospitalization periods. Patients underwent 3-phase bone scintigraphy using technetium-99m methylene diphosphonate, and the most distal site of the region displaying perfusion during the perfusion and early blood flow phase was marked as the amputation level. Amputation level was determined by 3-phase bone scintigraphy, Doppler ultrasound, and inspection of the infection-free clear region during surgery.
The amputation levels of the patients were as follows: finger in six (20%), ray amputation in five (16.6%), transmetatarsal in one (3.3%), Lisfranc in two (6.6%), Chopart in seven (23.3%), Syme in one (3.3%), below-the-knee in six (20%), above the knee in one (3.3%), knee disarticulation in one (3.3%), and two patients underwent amputation at other centers. After primary amputation, reamputation was performed on seven patients, and one patient was treated with debridement for wound site problems. No mortality was encountered during study.
We conclude that 3-phase bone scintigraphy prior to surgery could be a useful method to determine the amputation level in a diabetic foot. We conclude that further, comparative, more comprehensive, long-term, and controlled studies are required.
A retrospective study was performed on 26 patients who had undergone 27 digital amputations. All of the patients in the study had marked neuropathy. Sixty-five percent of the feet developed new ulcerations following initial hallux amputations, with 53% of the ulcerations occurring at distal digital sites. Fifty-three percent of the patients who had undergone hallux amputations required further amputations secondary to new ulcerations. In contrast, only 10% of the feet with initial lesser digit amputations developed new ulcerations. The authors discuss the biomechanics involved and the possible therapy for preventing these ulcerations and amputations.
This historical perspective highlights some of the pioneers, milestones, teams, and system changes that have had a major impact on management of the diabetic foot during the past 100 years. In 1934, American diabetologist Elliott P. Joslin noted that mortality from diabetic coma had fallen from 60% to 5% after the introduction of insulin, yet deaths from diabetic gangrene of the lower extremity had risen significantly. He believed that diabetic gangrene was preventable. His remedy was a team approach that included foot care, diet, exercise, prompt treatment of foot infections, and specialized surgical care.
The history of the team approach to management of the diabetic foot chronicles the rise of a new health profession—podiatric medicine and surgery—and emergence of the specialty of vascular surgery. The partnership among the diabetologist, vascular surgeon, and podiatric surgeon is a natural one. The complementary skills and knowledge of each can improve limb salvage and functional outcomes. Comprehensive multidisciplinary foot-care programs have been shown to increase quality of care and reduce amputation rates by 36% to 86%. Development of distal revascularization techniques to restore pulsatile blood flow to the foot has also been a major advancement.
Patients with diabetic foot complications are among the most complex and vulnerable of all patient populations. Specialized diabetic foot clinics of the 21st century should be multidisciplinary and equipped to coordinate diagnosis, off-loading, and preventive care; to perform revascularization procedures; to aggressively treat infections; and to manage medical comorbidities. (J Am Podiatr Med Assoc 100(5): 317–334, 2010)
Diabetic foot infections tend to lead to amputation. Partial first-ray resections are used to help salvage the foot and maintain bipedal ambulation. Losing the first metatarsophalangeal joint has biomechanical consequences that lead to further foot deformities and result in more proximal amputations of the ipsilateral limb, such as a transmetatarsal amputation.
We reviewed 48 patients (32 male and 16 female; mean age = 62.44) who underwent 50 partial first-ray resections between April 1, 2003, and July 31, 2009. These partial first-ray resections were done at various levels of the first metatarsal. We hypothesize that partial first-ray resections that require further bone resection will lead to poor biomechanics that can result in further amputation.
We found that out of 50 partial first-ray resections, 24 cases required further surgical intervention, 12 of which were a transmetatarsal amputation (TMA) (mean time between partial first-ray resection and TMA = 282.08 days). Forty-eight percent of patients did not require further surgical intervention and were considered a success.
Partial first-ray resections are not highly successful. Our study found a higher success rate compared to a previous study done by Cohen et al in 1991. Partial first-ray amputations can be a good initial procedure to salvage the foot and prolong a patient’s bipedal ambulatory status, thereby lowering the patient’s morbidity and mortality. (J Am Podiatr Med Assoc 102(5): 412–416, 2012)