Paul J. Kim

Wound Care: Biofilm and Its Impact on the Latest Treatment Modalities for Ulcerations of the Diabetic Foot

Biofilm is an increasingly important topic of discussion in the care of the chronic diabetic foot wound. Treatment modalities have focused on biofilm reduction or eradication through debridement techniques, topical therapies, negative pressure therapy, and ultrasound. In addition, advanced wound healing modalities, such as bioengineered alternative tissues, require optimal wound bed preparation with specific consideration of biofilm reduction before their application. Although fundamental principles of diabetic wound care still apply, critical thought must be given to biofilm before implementing a treatment plan for the closure of these complex wounds.

Complications of the Diabetic Foot

The diabetic foot is at high risk for complications because of its role in ambulation. Peripheral neuropathy and peripheral vascular disease can lead to chronic foot ulcers, which are at high risk for infection, in part attributable to areas of high pressure caused by lack of tolerance of the soft tissue and bone and joint deformity. If left untreated, infection and ischemia lead to tissue death, culminating in amputation. Treatment strategies include antibiosis, topical therapies, offloading, debridement, and surgery. A multidisciplinary team approach is necessary in the prevention and treatment of complications of the diabetic foot.

Role of the podiatrist in diabetic limb salvage

Podiatrists play an important role in the multidisciplinary team in diabetic limb salvage. Podiatry is a specialty that is licensed in the diagnoses and treatment of pathologies of the foot and ankle. The treatment includes both conservative and surgical modalities. Understanding the biomechanics of the lower extremity is principally emphasized in the education and training of a podiatrist. This is particularly important in the context of the diabetic foot where biomechanical abnormalities often precede ulcer development. Preventive ulcer development strategies employed by a podiatrist include regular monitoring, routine care of calluses, and insert/shoe recommendations. Further, clinic-based ulcer care as well as surgery that include prophylactic and acute intervention can translate to the preservation of a functional limb. Finally, continuous podiatric management can prevent ulcer recurrence through offloading strategies and diabetic foot education.

A solution for complex wounds: the evidence for negative pressure wound therapy with instillation

Negative pressure wound therapy with instillation and dwell time (NPWTi‐d) is an adjunctive therapy that can be used in the management of complex wounds with infection. NPWTi‐d incorporates the intermittent instillation of a topical solution to the wound in a programmed manner. Unlike standard negative pressure wound therapy, NPWTi‐d delivers topical wound solutions directly to the wound, allows the solution to dwell over the wound bed, and removes the solution during the negative pressure phase. The authors review the evidence for using NPWTi‐d and the role it may potentially play in helping to reduce hospital stay, number of debridement operations and cost.

Long-Term Outcomes of Permanent Cement Spacers in the Infected Foot

Abstract When osteomyelitis occurs in the infected foot, cement spacers have been used as a limb salvage tool. The aim of the present study was to assess the longevity and outcomes in high‐risk, low‐demand patients who have undergone resection of bone and subsequent placement of permanent antibiotic‐eluting cement spacers in the foot. A retrospective review case series of 30 patients who had undergone placement of a permanent antibiotic‐eluting cement spacer in the foot were evaluated for retention, spacer exchange, removal, amputation, and functional status. The minimum follow‐up time for inclusion was 12 months. Two thirds of all patients had successful spacers (n = 20) that were either retained (n = 14) or successfully exchanged (n = 6). One third of all patients experienced spacer failure (n = 10) and required removal. Of the 10 patients requiring spacer removal, 4 underwent removal with subsequent arthrodesis and 6 underwent removal with subsequent pseudoarthrosis. Also, 8 of these patients (26.7%) required partial foot amputation of the ipsilateral foot. These amputations were not directly related to the use or removal of the spacer. The average time to spacer removal or partial amputation was 20.9 (range 0.2 to 60.9) months. The longest retained spacer in the foot was 76 months at the last follow‐up visit. The longest exchanged spacer at the last follow‐up visit was 111 months. All surviving patients were ambulatory at the last follow‐up visit. &NA; Level of Clinical Evidence: 4

Effect of Semi‐quantitative Culture Results from Complex Host Surgical Wounds on Dehiscence Rates

The primary aim of this study was to determine the effect of positive bacterial cultures at the time of closure on dehiscence rates. Pre‐ and post‐débridement wound cultures from patients undergoing serial surgical débridement of infected wounds were compared with outcomes 30 days postoperatively. One‐hundred patients were enrolled; 35 were excluded for incomplete culture data. Sixty‐five patients were evaluated for species counts, including Coagulase negative Staphylococcus (CoNS), and semiquantitative culture data for each débridement. The post‐débridement cultures on the date of closure had no growth in 42 patients (64.6%) of which 6 dehisced (14.3%), and 36 remained closed; with no statistically significant difference in dehiscence rates (pu2009=u20090.0664). Pre‐débridement cultures from the 1st débridement of the 65 patients showed 8 patients had no growth, 29 grew 1 species, 19 grew 2 species, and 9 had 3–5 species. There was a reduction in the number of species and improvement of semiquantitative cultures with each subsequent débridement. The dehiscence rate for those who had 2 débridements (nu2009=u200942) was 21.4% at 30 day follow‐up and 21.7% in those who had 3 débridements (nu2009=u200923). The number of débridements had no statistical significance on dehiscence rates. The presence of CoNS on the day of closure was a statistically significant risk for dehiscence within 30 days (pu2009=u20090.0091) postoperatively. This data demonstrates: (1) positive post‐débridement cultures (scant/rare, growth in enrichment broth) at the time of closure did not affect overall dehiscence rates (pu2009=u20090.0664), (2) the number of species and semiquantitative culture results both improved with each subsequent débridement, (3) the number of surgical débridement did not influence postclosure dehiscence rates. (4) Positive cultures containing CoNS at the time of closure is a risk factor for dehiscence (pu2009=u20090.0091).

Combined free tissue transfer for the management of composite Achilles defects: functional outcomes and patient satisfaction following thigh-based vascularized reconstruction with a neotendon construct.

BACKGROUNDnu2003Functional outcomes and quality-of-life measures following salvage reconstruction of composite Achilles/posterior leg defects are limited. We present our experience with combined Achilles defect reconstruction utilizing free tissue transfer with vascularized neotendon constructs.nnnMETHODSnu2003Between 2011 and 2012, six patients underwent vascularized reconstruction of complex Achilles defects by a single surgeon. Demographic and functional data were collected for each patient. Subjective evaluation and quality-of-life measures were obtained preoperatively and postoperatively using American Orthopaedic Foot and Ankle Score (AOFAS) Ankle-Hindfoot and SF-36 scores. Early and late complications were noted for each case.nnnRESULTSnu2003All defects were reconstructed utilizing vascularized composite free tissue from the thigh. Average soft tissue defect was 76.7 cm(2) (range, 40-90 cm2) with a tendon gap of 7.8 cm (range, 5-10 cm). Mean follow-up was 17 months (range, 15-23 months). Flap survival was 100%. Overall range of motion of the reconstructed side was 82% of the unaffected side (48.2 degrees vs. 59 degrees, pu2009=u20090.004). Average percent increase in AOFAS and SF-36 scores were 71% (54 vs. 93, pu2009=u20090.0005) and 22% (86 vs. 104, pu2009=u20090.003), respectively. Operative revision was required for two patients with delayed-onset soft tissue infections and one donor site hematoma. Distal flap ischemia was managed with hyperbaric oxygen therapy in one patient. Functional and esthetic outcomes were judged good to excellent by all patients.nnnCONCLUSIONSnu2003Free tissue transfer with vascularized tendon reconstruction is a viable option for combined Achilles tendon/posterior leg defects, as both functional and quality-of-life measures appeared to be significantly improved at 1-year follow-up.

Assessment of Function after Free Tissue Transfer to the Lower Extremity for Chronic Wounds Using the Lower Extremity Functional Scale

Background Free tissue transfer is one option for preservation of form and function in the native limb, in the setting of soft tissue paucity. However, the data on patient functionality after microvascular intervention is inconsistently reported. The Lower Extremity Function Scale (LEFS) measures patient‐reported difficulty in carrying out 20 physical activities, on a Likert scale, the sum of which correlates with descriptive functional stages of 1‐5. We assess limb functionality in this cohort of microvascular patients using the LEFS survey. Methods A retrospective chart review was conducted at a single academic medical center of 101 consecutive free flaps, from 2011 to 2016. Of the flaps that met inclusion criteria, 39 had completed LEFS surveys. Mean LEFS scores were calculated, and the effects of risk factors such as diabetes, age, and smoking status were analyzed. Results The mean LEFS score after free tissue transfer was 50.3 (SD ± 21.1), with a mean follow up survey time of 3.0 years (SD ± 1.3). The score correlated with Stage 4 function, or independent community ambulation,” and age was the only demographic factor associated with decreased functionality in this group. This is compared with mean LEFS score of 43.1 (SD ± 18.4) in cohort of 55 below knee amputations (BKAs), and 38.3 (SD ± 14.9) in 28 above knee amputations (AKAs), both correlating with Stage 3 function: “limited community ambulation.” Conclusions Functional outcomes scores such as the LEFS demonstrate that patients can obtain an adequate level of functionality for independent community activity after free tissue transfer, although functional improvement diminishes with age.

Concordance Between Bone Pathology and Bone Culture for the Diagnosis of Osteomyelitis in the Presence of Charcot Neuro-Osteoarthropathy

Abstract The diagnosis of osteomyelitis (OM) is a challenging but critical pathology to uncover in patients with concomitant Charcot neuro‐osteoarthropathy (CN). The reference standard to diagnose OM is bone biopsy for histopathologic and microbiologic examination. The presence of CN, however, can have a negative effect on the accuracy of either method to identify OM. The aim of the present study was to examine the concordance between bone pathology and bone cultures in the presence of CN in the diagnosis of OM. A total of 286 patients with diabetes mellitus (DM) and CN were identified retrospectively, with 48 patients identified with OM. OM was confirmed by radiographs, magnetic resonance imaging, erythrocyte sedimentation rate, and C‐reactive protein, positive probe‐to‐bone test results, and intraoperative inspection. Seventy matched pairs of bone pathology and cultures with complete data were compared and analyzed. Statistical analysis included concordance, positive predictive value, negative predictive value, sensitivity, specificity, and kappa coefficient. Concordance between bone pathology and bone culture was 41.4%, with agreement in 29 of 70 paired specimens. The diagnostic test accuracy of histopathologic examination to diagnose OM in CN bone in our study was 51.4%. The diagnostic test accuracy of microbiologic examination to diagnose OM in CN bone was 50%. The positive predictive value was 72.2%. The negative predictive value was 44.1%. The sensitivity was 57.8%. The specificity was 60.0%. The kappa coefficient was 0.165. The reference standard method of histopathologic and microbiologic examination of bone specimens has little concordance and can lead to inaccurate or inconclusive information. The low sensitivity and specificity demonstrated in the present study does not support the use of the current reference standard method of bone biopsy for histologic and microbiologic diagnosis of OM when CN is present. Thus, a diagnosis of OM in patients with CN should only be considered in the presence of strong clinical, laboratory, and imaging correlates. &NA; Level of Clinical Evidence: 3

Diabetic Foot Ulcer: Prevention, Management, and Controversies

Purpose of ReviewThe purpose of this review is to update the reader on current practices and new developments in caring for the patient with a diabetic foot ulcer.Recent FindingsSurgical offloading may be superior to total contact casting but additional data is needed. Multidisciplinary care of the diabetic foot is effective at reducing amputations and reducing overall cost of care.SummaryPrevention of diabetic foot ulcers is most effective when diabetes and comorbidities are adequately managed and frequent foot care is performed by the patient daily and the clinician annually. Offloading is central to healing diabetic foot ulcers. Diabetic foot care is complex and requires a broad spectrum of medical, surgical, and orthotic specialists. When care occurs within a coordinated, multidisciplinary team, cost and outcomes improve.