A novel treatment approach to infected nonunion of long bones without systemic antibiotics
Strategies in Trauma and Limb Reconstruction
A novel treatment approach to infected nonunion of long bones without systemic antibiotics
Karim Z. Masrouha 0
Michael E. Raad 0
Said S. Saghieh 0
0 Department of Surgery, Orthopedics Division, American University of Beirut Medical Center , P. O. Box 11-0236, Riad El-Solh, Beirut 1107 2020 , Lebanon
1 Said S. Saghieh
Infected nonunion of long bones may require intravenous antibiotics over a lengthy period which may result in a high rate of complications. This study aims to assess the efficacy of local antibiotics used as a replacement to prolonged intravenous therapy. Thirteen patients with infected nonunion of long bones who failed at least one previous surgery were included. The infection was treated through extensive debridement, application of antibiotic-impregnated calcium sulphate pellets and the bone stabilized with external fixation. These patients were monitored for union and infection by clinical signs, laboratory values, and radiographs over a period of 24 months. The results support an eradication of infection and union in all patients with no antibiotic-associated complications. Local antibiotic delivery using calcium sulphate pellets provides an effective method for treatment of nonunion in long bones and is free of the complications from the intravenous route.
Infection; Nonunion; Local antibiotics; Calcium sulphate; Bone pellet; Long bones
Introduction
Infected nonunion is a dreaded complication of the long
bone fractures because its management is challenging to
both the patient and the orthopaedic surgeon [
1
].
Management involves surgical debridement, tissue reconstruction,
a long-course of antibiotics and opioids. The complexity
of care and its prolonged duration increases the cost of the
treatment for the patient [
2
]. In addition, adverse sequelae
may lead to bone loss, residual deformity, or even
amputation [
1
].
Recent advances in surgical technique have tilted the
balance towards limb salvage surgery [
1
]; however, only a few
high-quality studies exist which describe the most
beneficial and cost-effective post-operative antimicrobial treatment
approach [
3
]. Currently, the most widely used approach is
extensive surgical debridement followed by 6 weeks of
highdose intravenous (IV) antibiotics [
4
].
The effective antibiotic penetration and eradication of
infection requires 10–100 times the minimum inhibitory
concentration (MIC). This high dose is required due to the
bacterial biofilm formation and the local milieu at the
infection site [
5
]. When systemic antibiotics are administered for
a prolonged period, there is a significant risk of
complications. The IV route requires frequent replacement because
it is associated with IV-line thrombosis, infection, and
stenosis [
6
]. Other complications include, but are not limited
to, haematologic, renal, dermatologic, gastrointestinal, and
other metabolic problems such as lactic acidosis [
7
].
Certain antibiotics used in the treatment of osteomyelitis are
considered more toxic than others, particularly
aminoglycosides and vancomycin. These two antibiotics require
frequent measurement of trough and creatinine levels, further
contributing to the burden of treatment [
7
]. The high
frequency of Staphylococcus aureus infection and its high rates
of methicillin resistance [
8
] dictate the use of vancomycin
as a first-line treatment. Although effective, vancomycin is
associated with nephrotoxicity in as many as 43% of patients
in some studies [
9
].
The use of a local antibiotic delivery conduit was
popularized in Europe during the 1970s [
5
]. It is associated with
lower rates of systemic antibiotic toxicity, allowed for filling
of the defect created by extensive debridement, and was
considerably cheaper than prolonged courses of systemic
antibiotics [
8
]. Polymethyl-methacrylate (PMMA) is one of the
most commonly used antibiotic conduits today but requires
further surgery for removal and may be associated with bead
infection after elution of the antibiotic has completed [
10
].
Recently, synthetic calcium sulphate has gained popularity
as an attractive alternative due to its predictable drug-eluting
properties, osteoconductivity, biodegradability and obviating
additional surgery for removal [
11
].
The beneficial effects of this treatment modality
necessitate further study to document its efficiency in the absence
of systemic antibiotic use. The aim of our study is to
evaluate the resolution of infection and bone healing in patients
with infected nonunion of long bones treated with extensive
debridement, bone reconstruction and
antibiotic-impregnated calcium sulphate pellets without subsequent use of
systemic antibiotics.
Materials and methods
This is a retrospective cohort study of 13 consecutive
patients with infected nonunion of long bone from two
affiliated medical centres between 2003 and 2012. Institutional
review board approval was obtained fro (...truncated)