40

Diagnosis and Management

of Orthopaedic Infection

after Stifle Surgery

Noel M.M. Moens ̈

Introduction

Since ancient times, surgical infections have
always been a challenge for surgeons. Although
significant discoveries have been made over
the past century, current understanding of sur-
gical infections and widespread use of antibi-
otics have all but eliminated the risk of sur-
gical site infection (Alexander 1985). Although
the risk of developing surgical infection and
the chances of dying from infection have sub-
stantially decreased, surgeons are now faced
with the increasing prevalence of multi-drug-
resistant bacteria (Cohen 1992). Infections that
are untreatable with the current range of antibi-
otics are becoming more frequent and cause a
significant burden on the patient’s well-being
and on the cost of healthcare.
The overall incidence of infection in human
surgery has been reported to be between 2% and
5%. However, incidence varies based on the spe-
cific surgery, specific risk factors, and wound
classification (Culveret al. 1991; Anderson 2011;
Eisenberg 2012). Clean elective orthopaedic
procedures have the lowest infection rates,
while contaminated or dirty procedures are
associated with higher rates. Although slightly
higher, the rate of surgical infection in veteri-
nary surgery parallels the human surgery, with

infection rates for clean procedures reported

to be around 2.5% (Vasseuret al. 1992; Eug-

steret al. 2004). Over the past two decades,

several new procedures have been developed

for the treatment of various stifle conditions.

Although most are clean elective procedures,

higher infections rates than expected have often

been reported.

Definition

Surgical site infections (SSI) are infectious

complications that manifest at the incision site

of a surgical patient, and are the result of a com-

bination of host, pathogen, and environmental

factors resulting in the establishment of infec-

tion (Mangramet al. 1999; Nelson 2011). In order

to standardize the definition of SSI, the United

States Centers for Disease Control and Preven-

tion (CDC) has defined several categories of

SSI and has provided criteria for its diagnosis

(Table 40.1). It must be noted that although iso-

lation and culture of the causal agent adds to the

validity of the diagnosis, a positive culture is not

required for the diagnosis of SSI. Some aspects

of the definition can still be open to interpre-

tation and will continue to generate variability

in the results. For example, inflammation and

Advances in the Canine Cranial Cruciate Ligament, Second Edition. Edited by Peter Muir. © 2018 ACVS Foundation.
This Work is a co-publication between the American College of Veterinary Surgeons Foundation and Wiley-Blackwell.

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