Musculoskeletal Infections PDF

Preface

The treatment of musculoskeletal infections continues to evolve. We have gleaned our knowledge from past and current masters and our patients. Our knowledge will be expanded and passed on to future generations. We are but a bridge between the past and future.

The United Nations has declared the years 2000–2010 the Bone and Joint Decade. One of the major components of bone and joint disorders are musculoskeletal infections. We have spent the past 20 years treating patients with musculoskeletal infections and conducting research on these difficult infections.

When we first started this endeavor there was not much that could be done for such patients, especially those with long bone osteomyelitis and severe diabetic foot infections. In addition, there was not much interest in musculoskeletal infections. These infections were considered more of a nuisance than a topic for serious clinical and basic science research. At that time, the gold standard was debridement or amputation and six weeks of parenteral antibiotics. Over the past two decades, treatment of these infections has changed. We now have better staging systems, surgeries, antibiotics, and adjunctive therapies. The interest in this topic has also grown. We have a Musculoskeletal Infections Society, and more clinical and basic research is being done in the field. The purpose of this book is to outline the current concepts for the treatment of musculoskeletal infections and to explore emerging techniques for treatment.

The first chapter, on the basic science of these infections, explores the statement, ‘‘The environment is everything and the bacteria are nothing.'' Physicians must understand the location of the infection (environment), the infecting organism(s), and the defenses of the host in order to treat and eradicate the infection. The triad of infection is described in detail including the infecting pathogen, the properties of the host, and the source and location of the infection.

In order to understand and treat musculoskeletal infections we must have treatment templates. Classification of musculoskeletal infections helps provide this template. Chapter 2 describes a staging system for osteomyelitis that helps stratify the infection and guide therapy.

Musculoskeletal infections are more difficult to treat in compromised hosts. The reasons for the difficulty are carefully explored in the chapter on systemically and locally immunocompromised hosts. Physicians must develop a systematic approach for patients with compromised immune systems who present with soft tissue, joint, and bone infections.

It is better to prevent musculoskeletal infections rather than treat them. Chapter 4 explores the history and current rationale for the use of prophylactic antibiotics in musculoskeletal infections. The timing of antibiotic administration, role of interoperative dosing, duration of use, and choice of antibiotic(s) are also discussed.

Specific musculoskeletal infections and the state-of-the-art treatment are described in the chapters on open fractures, long bone osteomyelitis, septic arthritis, hand infections, total hip infections, total knee infections, diabetic foot infections, and vertebral osteomyelitis. Vertebral osteomyelitis is further stratified into hematogenous pyogenic infection of the spine, postoperative infections of the spine, and granulomatous infections of the spine.

The treatment of osteomyelitis in neonates, infants, and children is different from that in adults. Neonates and infants are compromised hosts, while children are superhosts and are easier to treat than adults. Because of these differences, we have included a chapter on pediatric osteomyelitis.

The mainstays of musculoskeletal infections are surgery and culturedirected antibiotic therapy. Specific antibiotics that are useful in musculoskeletal infections and their potential toxicities are described in detail in Chapter 16. Included in that chapter is a section on resistant organisms and their treatment.

Surgery is usually mandatory for the treatment of musculoskeletal infections. The standard surgeries have been described in the sections on specific infections. Muscle flaps are useful in almost all the infections, especially when there is soft-tissue compromise. While the rationale for the use of muscle flaps is described in the specific chapters, the technical aspects and details are presented in Chapter 17.

The management of musculoskeletal infections includes antibiotics, surgery, and adjunctive therapy. The chapter on adjunctive therapy discusses the roles and effectiveness of such therapies in the management of musculoskeletal infection, including bioimplants, electrical stimulation, and hyperbaric oxygen therapy. The use of bioimplants includes PMMA, collagen hydroxyapatite, synthetic polymers, and fibrin sealant. Bioimplants are being used for the delivery of antibiotics and bone morphogenic protein, as scaffolding, and as a vehicle for osteogenic cell delivery. The use of bioimplants is undergoing an expansion and has the potential to change how we treat musculoskeletal infections.

The final chapter discusses the state of the art in gene therapy in musculoskeletal repair. Management of nonhealing wounds and bone defects has been aided by the development of new agents, including growth factors, cytokines, and bone morphogenic proteins. A way to get these agents to the right location is through gene therapy. The most attractive feature of gene therapy is that therapeutic proteins can be delivered locally to the appropriate site in relatively high concentrations and in a sustained fashion. Current goals include the improvement of transfection efficacy and specificity, optimizing inducible or cell-type specific promoters, and improving local application techniques. Gene therapy will change how we treat musculoskeletal infections and their complications in the future.

Musculoskeletal infections are common problems that involve a variety of specialties, including orthopaedics, infectious diseases, plastic surgery, vascular surgery, internal medicine, pediatrics, family medicine, podiatry, and others. We felt it was important to write a comprehensive book where all of these specialties could find common ground. There are numerous articles and book chapters spread across different specialties but it is difficult to find the important and pertinent information in one place. We hope that this book will fill that void.

We would like to thank our patients who have provided guidance. We are indebted to Kristi Overgaard, who was the driving force behind this book. Ms. Overgaard organized, edited, and shepherded our book to the publishers. Acknowledgment must also be made to others who directly and heavily contributed to this publication; for this we gratefully thank Drs. Joe Wang, Luca Lazzarini, Mark Shirtliff, Jack LeFrock, and Shazia Amina. We would also like to thank the many contributors whose dedication to their patients and to the treatment of musculoskeletal infections contributed not only to this book, but also to the entire field of musculoskeletal infections.