The Management and Clinical Outcome of the Charcot Foot

Abstract

Osteoporoosilääkkeestä ei hyötyä diabeetikon jalkaongelmassa

Diabeteksen esiintyvyys kasvaa kaikkialla maailmassa ja siihen liittyvät jalkaongelmat, kuten haavaumat, infektiot, kuoliot, Charcot n jalka ja amputaatiot ovat yksi merkittävimmistä diabetespotilaiden sairaalahoitoa aiheuttavista syistä. Charcot n jalka on invalidisoiva diabeteksen aiheuttama jalkaterän tai nilkan nivel- ja luusairaus. Tauti johtaa usein nopeasti etenevään jalkaterän tai nilkan luun tuhoutumiseen ja pysyviin virheasentoihin, joihin liittyy kohonnut amputaation riski.

Väitöstutkimus osoitti, ettei osteoporoosilääkkeenäkin käytetty zoledronaatti nopeuttanut Charcot n jalan paranemista. Taudin toteaminen todettiin hankalaksi ja usein viiveet oikeaan diagnoosin olivat pitkiä. Mitä aiemmin oikeaan diagnoosiin päästiin, sitä parempi oli potilaiden pitkäaikaisennuste.

Diabetes mellitus is an endemic disease affecting up to six percent of population worldwide. In Finland, over 300,000 patients have a diagnosis of diabetes and the number is exponentially increasing. Diabetic foot problems; such as ulceration, infection, gangrene, Charcot foot and amputation are a major source of morbidity and a leading cause of hospitalization for patients with diabetes. A non-infectious destruction of bones and joints in a neuropathic extremity was first described more than 100 years ago and has since come to be known by eponym Charcot foot. Today diabetes is the most common cause of Charcot foot, which is recognised as one of the most devastating and disabling complication of diabetes and among the most important risk factors for plantar ulcer formation and subsequent amputation. The understanding of the basic pathophysiological mechanisms of Charcot foot has gradually led to the development of new treatment strategies and the purpose of the present study was to investigate the effect of zoledronic acid (bisphosphonate) on the treatment of acute Charcot foot in a prospective, randomized controlled trial. In addition, the long-term effects of chronic Charcot foot on patient s clinical outcome and quality of life were investigated and a comprehensive analysis of historical patient series was conducted.

The study population consisted of Charcot foot patients treated at the Tampere University Hospital Diabetic Foot Clinic during period 1994-2007. The first retrospective data was obtained from the patient records of the Diabetic Foot Clinic and was collated with the Hospital Discharge Register in order to assess the patient demographics and management details of a historical patient series with Charcot foot. The second data set consisted of prospectively enrolled patients (2002-2007) with acute midfoot Charcot foot and compared clinical resolution and bone mineral density changes during the treatment of acute Charcot foot with and without zoledronic acid. The fourth set data was also identified from the patient register of the Diabetic Foot Clinic and was a cross-sectional descriptive study assessing long-term clinical outcome and quality of life in patients with Charcot foot and at least five years of follow-up.

The diagnosis of acute Charcot foot is demanding and significant delays in diagnosis were common. The average delay was 29 weeks and the most frequent incorrect diagnoses were erysipelas, deep venous thrombosis, gout, arthritis, fracture or osteomyelitis. The prospective study failed to show any clinical benefit (reduced immobilisation time) with zoledronic acid as an adjuvant in the treatment of acute midfoot Charcot foot. The median immobilisation time in the placebo group was 20 weeks, but this lengthy immobilisation did not lead to an obvious disuse osteoporosis of the hip in the Charcot foot affected side after six months of treatment. Management with zoledronic acid led to a significant increase of the hip bone mineral density in both sides compared to placebo, but the clinical significance of this was uncertain. In the long-term follow-up study 67% of patients had ulceration during follow-up and 40% were ulcerated more than once. Fifty percent of patients were managed surgically with an increase in surgery 4 years post diagnosis. Chronic Charcot foot was found to impair patient s physical functioning and general health but did not affect mental health. Long-term functional outcome of patients with Charcot foot is usually relatively good, mainly due to the absence of pain and if the correct diagnosis is reached early.