Commentary

Progress in care of the diabetic foot

Historically, Charcot neuroarthropathy hip (CNH) was deemed a contraindication for total hip arthroplasty (THA). However, as implant design and surgical techniques advance, THA for CNH has been performed and documented in literature. Information regarding the outcomes of THA for CNH is limited. The objective of the study was to assess outcomes following THA in patients who have CNH.

Patients who have CNH underwent primary THA and had at least 2 years of follow-up were identified in a national insurance database. For comparison, a 1:10 matched control cohort of patients who did not have CNH was created based on age, sex, and relevant comorbidities. Eight hundred and ninety-five CNH patients who underwent primary THA were compared to 8,785 controls. Medical outcomes, emergency department visits, hospital readmissions, and surgical outcomes including revisions between cohorts were evaluated using multivariate logistic regressions.

The CNH patients were found to have higher risks of 90-day wound complications (P = .014), periprosthetic joint infection (P = .013) (P = .021), dislocation (P < .001) (P < .001), aseptic loosening (P = .040) (P = .002), periprosthetic fracture (P = .003) (P < .001), and revision (P < .001) (P < .001) at 1-year and 2-year follow-up, respectively.

While patients who have CNH are at a higher risk of wound and implant-related complications, they are comparatively lower than previously reported in literature. Orthopaedic surgeons should be cognizant of the increased risk in this population to provide appropriate preoperative counseling and enhanced perioperative medical management.

Charcot's neuroarthropathy is a destructive complication of the joints, which is often found in people with diabetes with peripheral neuropathy. Despite the fact that its description was published almost 130 years ago, its pathophysiology, diagnosis, and treatment remain areas that need to be described. Thanks to the use of bone remodelling, new therapeutic classes have emerged, we hope that this review will shed light on the pathology from its discovery through to the current state of knowledge on its classification, diagnosis and treatment methods.

Infection is a common epiphenomenon of advanced diabetic foot disease and the most common reason for diabetes-related hospitalizations and lower extremity amputations. Major advances have been made in the past three decades in our understanding and management of diabetic foot infections (DFIs). The optimal treatment of DFIs clearly involves multidisciplinary input.

A comprehensive search of the literature on DFIs from January 1960 through June 2015 was performed, with an emphasis on information published in the past 30 years.

There have been many new insights into the microbiology, diagnosis, and treatment of DFIs, although the implementation of this knowledge in clinical practice has been suboptimal. Today, the use of evidence-based guidelines, multidisciplinary teams, and institution-specific clinical pathways helps guide optimal care of this multifaceted problem. Patients are more often treated in the ambulatory setting, with antibiotic regimens that are more targeted, oral and shorter course, and with more conservative (but earlier) surgical interventions. New diagnostic and therapeutic methods are being developed at an accelerating pace.

The worldwide increase in the incidence of diabetes and longer lifespan of diabetic patients will undoubtedly increase the incidence of DFIs. Clinicians caring for diabetic patients should have an understanding of current methods for preventing, diagnosing, and treating DFIs.

To identify factors associated with patients receiving foot examinations by primary health care nurses.

A cross-sectional survey of 287 randomly sampled primary health care nurses, from a total of 1091 in Auckland, completed a postal self-administered questionnaire and telephone interview. Biographical and diabetes management details were collected for 265 diabetes patients consulted by the nurses on a randomly selected day.

A response rate of 86% was achieved. Nurses examined patient's feet in 46% of consultations. Controlling for demographic variables, foot examinations were associated with age, odds ratio (1.25, 95% CI 0.57–2.74) for patients aged 51–65 years and >66 years (2.50, 1.08–5.75) compared with those ≤50 years, consultations by district compared with practice nurses (14.23, 95% CI 3.82–53.05), special programme consultations compared with usual follow-up consults (8.81, 95% CI 2.99–25.93) and length of consultation (1.89, 0.72–4.97) for 15–30 min and (4.45, 95% CI 1.48–13.41) >30 min compared with consultations ≤15 min, or for wound care (2.58, 1.01–6.61).

Diabetes foot examinations by primary health care nurses varies greatly, and are associated with characteristics of the patient (age, need for wound care) and the consultation (district nurses, diabetes programme and duration).

In diabetes, foot ulceration may result from increased skin fragility. Retinoids can reverse some diabetes-induced deficits of skin structure and function, but their clinical utility is limited by skin irritation. The effects of diabetes and MDI 301, a nonirritating synthetic retinoid, and retinoic acid have been evaluated on matrix metalloproteinases (MMPs), procollagen expression, and skin structure in skin biopsies from nondiabetic volunteers and diabetic subjects at risk of foot ulceration using organ culture techniques.

Zymography and enzyme-linked immunosorbent assay were utilized for analysis of MMP-1, -2, and -9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) and immunohistochemistry for type I procollagen protein abundance. Collagen structure parameters were assessed in formalin-fixed, paraffin-embedded tissue sections.

The % of active MMP-1 and -9 was higher and TIMP-1 abundance was lower in subjects with diabetes. Type 1 procollagen abundance was reduced and skin structural deficits were increased in diabetes. Three μM MDI 301 reduced active MMP-1 and -9 abundance by 29% (P<.05) and 40% (P<.05), respectively, and increased TIMP-1 by 45% (P=.07). MDI 301 increased type 1 procollagen abundance by 40% (P<.01) and completely corrected structural deficit scores. Two μM retinoic acid reduced MMP-1 but did not significantly affect skin structure.

These data indicate that diabetic patients at risk of foot ulceration have deficits of skin structure and function. MDI 301 offers potential for repairing this skin damage complicating diabetes.