The utility of wound debridement has expanded to include the management of all chronic wounds, even in the absence of infection and gross necrosis. Biofilms, metalloproteases on the wound base, and senescent cells at the wound edge irreversibly change the physiologic features of wound healing and contribute to a pathologic, chronic inflammatory environment. The objective of this review is to provide surgeons with a basic understanding of the processes of debridement in the noninfected wound. (J Am Podiatr Med Assoc 100(5): 353–359, 2010)
Background: Walking at various speeds and durations may result in different peak plantar pressure (PPP). However, there is no study comparing the effect of walking speeds and durations on PPP. The purpose of this study was to explore whether different walking speeds and durations significantly change PPP and establish a normal response in healthy people.
Methods: An in-shoe plantar pressure system was used to measure PPP under the first toe, first metatarsal, second metatarsal, and heel regions in 12 healthy, young people. All participants performed six walking trials at three speeds (3, 6, and 9 km/h) and for two durations (10 and 20 min). The 3 × 2 two-way analysis of variance was used to examine the main effects of speeds and durations and their interaction.
Results: The results showed that walking speeds significantly affected PPP and that walking duration did not. No interaction between the walking speed and duration was observed. Peak plantar pressure values under the first toe and the first metatarsal head were significantly higher (P < .05) at 9 km/h (509.1 ± 314.2 kPa and 591.4 ± 302.4 kPa, respectively) than at 3 km/h (275.4 ± 168.7 kPa and 369.4 ± 205.4 kPa, respectively) after 10-min walking.
Conclusions: People at risk for foot ulcers may use slow and brisk walking for exercise to reduce PPP, thus reducing risk for foot ulcers. Our study demonstrated that slow running at 9 km/h significantly increases PPP.
Background: Diabetic lower-extremity disease is the primary driver of mortality in patients with diabetes. Amputations at the forefoot or ankle preserve limb length, increase function, and, ultimately, reduce deconditioning and mortality compared with higher-level amputations, such as below-the-knee amputations (BKAs). We sought to identify risk factors associated with amputation level to understand barriers to length-preserving amputations (LPAs).
Methods: Diabetic lower-extremity admissions were extracted from the 2012-2014 National Inpatient Survey using ICD-9-CM diagnosis codes. The main outcome was a two-level variable consisting of LPAs (transmetatarsal, Syme, and Chopart) versus BKAs. Logistic regression analysis was used to determine contributions of patient- and hospital-level factors to likelihood of undergoing LPA versus BKA.
Results: The study cohort represented 110,355 admissions nationally: 42,375 LPAs and 67,980 BKAs. The population was predominantly white (56.85%), older than 50 years (82.55%), and male (70.38%). On multivariate analysis, living in an urban area (relative risk ratio [RRR] = 1.48; P < .0001) and having vascular intervention in the same hospital stay (RRR = 2.96; P < .0001) were predictive of LPA. Patients from rural locations but treated in urban centers were more likely to receive BKA. Minorities were more likely to present with severe disease, limiting delivery of LPAs. A high Elixhauser comorbidity score was related to BKA receipt.
Conclusions: This study identifies delivery biases in amputation level for patients without access to large, urban hospitals. Rural patients seeking care in these centers are more likely to receive higher-level amputations. Further examination is required to determine whether earlier referral to multidisciplinary centers is more effective at reducing BKA rates versus satellite centers in rural localities.
The Society for Vascular Surgery (SVS) and the American Podiatric Medical Association (APMA) recognize the beneficial impact of a multidisciplinary team approach on the care of patients with critical limb ischemia, especially in the diabetic population. As a first step in identifying clinical issues and questions important to both memberships, and to work together to find solutions that will benefit the shared patient, the two organizations appointed a representative group to write a joint statement on the importance of multidisciplinary team approach to the care of the diabetic foot. (J Am Podiatr Med Assoc 100(4): 309–311, 2010)
The skin on human feet presents unique environments for the proliferation of potentially pathogenic commensals. This study examined microflora changes on healthy intact skin under a semiocclusive dressing on the medial longitudinal arch of the foot to determine changes in growth, distribution, and frequency of microflora under the dressing.
Nine human participants wore a low-adherent, absorbent, semiocclusive dressing on the medial longitudinal arch of the left foot for 2 weeks. An identical location on the right foot was swabbed and used as a control. Each foot was swabbed at baseline, week 1, and week 2. The swabs were cultured for 48 hours. Visual identification, Gram staining, DNase test agar, and a latex slide agglutination test were used to identify genera and species.
Microflora growth was categorized as scant (0–10 colony-forming units [CFU]), light (11–50 CFU), moderate (51–100 CFU), or heavy (>100 CFU). Scant and light growth decreased and moderate and heavy growth increased under the dressing compared with the control. Seven different genera of bacteria were identified. Coagulase-negative Staphylococcus spp appeared most frequently, followed by Corynebacterium spp.
Changes in microflora distribution, frequency, and growth were found under the dressing, supporting historical studies. Microflora changes were identified as an increase in bioburden and reduction in diversity. The application of similar methods, using more sophisticated identification and analysis techniques and a variety of dressings, could lead to a better understanding of bacterial and fungal growth under dressings, informing better dressing selection to assist the healing process of wounds and prevent infection.
Staphylococcus pseudintermedius is an emerging zoonotic pathogen that is very similar to human Staphylococcus pathogens, particularly multidrug-resistant Staphylococcus aureus. Recent reports have indicated that S pseudintermedius is easily transmitted between pets (mainly dogs) and owners because of these similarities. Although this pathogen has been associated with diabetic foot infections, it has not yet been described in the podiatric medical literature. In this case report, we present a diabetic foot infection in a 61-year-old man that was refractory to multiple rounds of antibiotic drug therapy. Deep wound cultures eventually grew S pseudintermedius, which was the first known case of this pathogen reported in our hospital system.
Persons with diabetes have a higher incidence of fractures compared with persons without diabetes. However, there is little published information concerning the deleterious effect of late-stage diabetes on fracture healing. There are no studies using animal models that evaluate the effect of advanced diabetes on fracture healing. The purpose of our study was to evaluate cytokine expression, specifically macrophage inflammatory protein 1 (MIP-1) and vascular endothelial growth factor, in fracture healing in a type 2 diabetes rat model.
We evaluated biomarker expression after femur fracture using a rat model. The two groups consisted of 24 Zucker diabetic rats (study group) and 12 Zucker lean rats (control group). An independent reviewer was used to assess delayed union. We evaluated serum samples 2, 4, 7, and 14 days after surgery for MIP-1, vascular endothelial growth factor, leptin, and other cytokine levels.
At 3 weeks, Kaplan-Meier estimates showed that 45.8% of femur fractures in Zucker diabetic rats had healed, whereas 81.8% of those in Zucker lean rats had healed (P = .02). A logistic regression model to predict fast healing that included the three cytokines and diabetes status showed that the only factor achieving significance was MIP-1α. Vascular endothelial growth factor was the only biomarker to show significance compared with delayed healing.
These results confirm significant differences in biomarker expression between diabetic and nondiabetic rats during bone healing. The key factors for bone healing may appear early in the healing process, whereas differences in diabetes versus nondiabetes are seen later in the healing process. Increased levels of MIP-1α were associated with the likelihood of delayed healing.
Background: We sought to determine the similarity of pathogens isolated from soft tissue and bone in patients with diabetic foot infections. It is widely believed that soft-tissue cultures are adequate in the determination of causative bacteria in patients with diabetic foot osteomyelitis. The culture results of specimens taken concurrently from soft-tissue and bone infections show that the former does not predict the latter with sufficient reliability. We sought to determine the similarity of pathogens isolated from soft tissue and bone in patients with diabetic foot infections.
Methods: Forty-five patients with diabetic foot infections were enrolled in the study. Patients had to have clinically suspected foot lesions of grade 3 or higher on the Wagner classification system. In patients with clinically suspected osteomyelitis, magnetic resonance imaging, scintigraphy, or histopathologic examination were performed. Bone and deep soft tissue specimens were obtained from all patients by open surgical procedures under aseptic conditions during debridement or amputation. The specimens were compared only with the other specimens taken from the same patients.
Results: The results of bone and soft-tissue cultures were identical in 49% (n = 22) of cases. In 11% (n = 5) of cases there were no common pathogens. In 29% (n = 13) of cases there were more pathogens in the soft-tissue specimens; these microorganisms included microbes isolated from bone cultures. In four patients (9%) with culture-positive soft-tissue specimens, bone culture specimens remained sterile. In one patient (2%) with culture-positive bone specimen, soft-tissue specimen remained sterile.
Conclusion: Culture specimens should be obtained from both the bone and the overlying deep soft tissue in patients with suspected osteomyelitis whose clinical conditions are suitable. The decision to administer antibiotic therapy should depend on these results. (J Am Podiatr Med Assoc 98(4): 290–295, 2008)
Background: Plantar first metatarsal ulcerations pose a difficult challenge to clinicians. Etiologies vary and include first metatarsal declination, cavus foot deformity, equinus contracture, and hallux limitus/rigidus. Our pragmatic, sequential approach to the multiple contributing etiologies of increased plantar pressure sub–first metatarsal can be addressed through minimal skin incisions.
Methods: A retrospective review was performed for patients with surgically treated preulcerations or ulcerations sub–first metatarsal head. All of the patients underwent a dorsiflexory wedge osteotomy, and the need for each additional procedure was independently assessed. Equinus contracture was treated with Achilles tendon lengthening, cavovarus deformity was mitigated with Steindler stripping, and plantarflexed first ray was treated with dorsiflexory wedge osteotomy.
Results: Eight patients underwent our pragmatic, sequential approach for increased plantar pressure sub–first metatarsal, four with preoperative ulcerations and four with preoperative hyperkeratotic preulcerative lesions. The preoperative ulcerations were present for an average of 25.43 weeks (range, 6.00–72.86 weeks), with an average size of 0.19 cm3 (median, 0.04 cm3). Procedure breakdown was as follows: eight first metatarsal osteotomies, four Achilles tendon lengthenings, and six Steindler strippings. Postoperatively, all eight patients returned to full ambulation, and the four ulcerations healed at an average of 24 days (range, 15–38 days). New ulceration occurred in one patient, and postoperative infection occurred in one patient. There were no ulceration recurrences, dehiscence of surgical sites, or minor or major amputations.
Conclusions: The outcomes in patients surgically treated for increased plantar first metatarsal head pressure were evaluated. This case series demonstrates that our pragmatic, sequential approach yields positive results. In diabetic or high-risk patients, it is our treatment algorithm of choice for increased plantar first metatarsal pressure.