The management of osteomyelitis in the adult

Abstract

Background and purpose

Osteomyelitis (OM) is considered one of the most challenging medical conditions an orthopaedic surgeon has to face. Much debate is present concerning diagnosis and treatment, especially about differences between acute and chronic forms of the condition. The main aim of the present work is to show the key points where research should be implemented.

Methods

Online database were searched to find evidence about the clinical management of osteomyelitis. Clinical randomized trials, case series, prospective cohort studies reporting on diagnosis and treatment of acute and chronic osteomyelitis were taken into consideration. Cadaveric studies, laboratory studies, case reports, review articles and meta-analyses were excluded. Furthermore, studies concerning implant related OM were excluded. Studies in English, Spanish and French were considered in this process of inclusion. The cohorts of all the included studies were composed of adult patients.

Results

The main growpoints concerning OM are the identification of a correct laboratory test array to allow a prompt diagnosis and provide a sensitive and specific detection of the bacterial species involved, along with antibiotic drug resistance; optimal imaging techniques, according to the phase of the infection, have to be performed, to avoid unnecessary medical expenses; the identification of a suitable compromise between intravenous and oral drugs administration. A flow chart is proposed for optimal clinical management of this pathology.

Conclusion

More work should be carried out to clarify the main issues concerning the clinical management of osteomyelitis in adult patients.

Introduction

Osteomyelitis is one a most challenging condition for both physicians and patients, with an incidence of 21.8 per 100,000 person/years in the United States.¹ It an inflammatory state of the bone caused by a microorganism; it can involve either the trabecular or the cortical bone, the bone marrow and the periosteum.² Osteomyelitis can be generally classified in four categories: acute, chronic, diabetic foot related, and implant related, but several and more articulated classifications have been developed. A classification for osteomyelitis (OM) has been proposed by Waldvogel in 1970, based on the source of infection.³ Three different conditions have been considered: OM caused by local spreading from a contiguous focus of infection; OM secondary to vascular insufficiency (more likely to develop in the diabetic foot); and haematogenous OM, derived from a condition of bacteraemia.³ This classification is useful for pathological definition of the disease. A more clinical classification was developed by Cierny and Mader in 1983 for chronic OM.⁴ This classification is widely used in daily clinical practice, and has shown a good prognostic value. The main histo-pathological lesion of OM is the sequestrum, which consists in formation of necrotic bone, which lays in the midst of the infected tissue.² A sequestrum derives from the destruction of bone tissue and bone matrix from inflammatory factors, including leucocytes and cytokines that increase the osteoclasts activity. Because of the lack of vascularization, and hence the impossibility to be reached by immunity cells and drugs, the sequestrum is the cause of persistent infection, since the pathogens are embedded in it. Several bacteria and fungi are common infecting microorganism. Staphylococcus aureus and Staphylococcus epidermidis are the most common pathogens, because of their presence in the normal flora of the skin. Other relevant bacteria are Enterococcus spp, Streptococcus spp; among the fungi, Candida5, 6 and Aspergillus⁶ have been reported.

The diagnosis of OM is using a multidisciplinary approach involving laboratory medicine, imaging, and pathology. Therapy is based on a multi-area treatment involving antibiotic drugs administration and surgery. The present review collected and analysed the recent scientific evidence about the epidemiology and clinical management of OM, giving an overview on the most common pathogens causing OM, diagnostic techniques and therapeutic options for acute and chronic OM.