Incidence of
postoperative anterior cruciate ligament reconstruction infections: Graft
choice makes a difference

G, Inacio M, Reynolds S, Desmond J, Maletis M, Funahashi T. Am J Sports Med.

Take Home Message: There
is a low risk of surgical site infection after an ACL reconstruction.  Patients with a hamstring autograft may be at
higher risk for surgical site infections than patients with a bone-patellar
tendon-bone autograft.

is always a concern after surgery.  Although
uncommon, post-operative infections after an anterior cruciate ligament (ACL) reconstruction
can be devastating. Graft selection may influence the rate of infection, if
this can be verified then it may help clinicians better explain to patients the
risks and benefits associated with each graft choice. The purpose of this study
was to determine the incidence of superficial and deep surgical site infections
(SSIs) after ACL reconstruction.  Furthermore,
Maletis and colleagues analyzed data from the Kaiser Permanente Anterior
Cruciate Ligament Reconstruction Registry, a large community-based cohort, and
evaluated if patient demographic characteristics or graft type were associated
with SSIs. In the analyses, the authors included patients that received a primary
ACL reconstruction that used a bone-patellar tendon-bone autograft, hamstring
tendon autograft, or allograft between February 2005 and September 2010.  The researchers performed a chart review of
all participants and classified any SSI as either superficial or deep.  A superficial SSI occurred within 30 days of
surgery, involved the skin and subcutaneous tissue and had at least one of the
following: purulent drainage (pus), cultured organisms, signs or symptoms of
infection, or a diagnosis of infection from a physician.  The infection was deep if it occurred up to a
year after surgery, involved deep tissues, and had at least one of the
following: purulent drainage (pus), incision spontaneously dehisces or is opened surgically
and has a positive culture, signs or symptoms of infection, presence of an abscess,
other evidence of infection, or diagnosis of infection.  Among the 10,626 patients included in this
study, 51 patients developed an infection, 34 deep and 17 superficial.  Hamstring tendon autografts had the highest
rate of overall SSI (0.74%) as well as deep infection (0.61%) compared with
knees that received a bone-patellar tendon-bone autograft (0.34%, 0.07%;
respectively) or allograft (0.39%, 0.25%; respectively).  Staphylococcus
was the most commonly identified organism occurring in 56% of deep infections
and in 77% of superficial infections.  Finally,
individuals with a higher body-mass index (BMI) were more likely to develop a
superficial SSI.

study, which had a very low overall rate of infection after ACL reconstruction
(0.48%), had a large sample size that selected patients from various regions of
the United States allowing the results to be applied to the general population
in the United States. However, the authors did not examine functional outcomes
of the patients.  This limitation should
be considered by clinicians when evaluating this study because hamstring grafts
are a common choice for ACL reconstruction and they may promote better functional
outcomes (see related posts below). The authors did not identify reasons for
infection; therefore, clinicians with patients who are undergoing ACL
reconstruction, particularly using a hamstring autograft, should pay close
attention to the incision sites for possible infections. Recognizing the four
signs of infection, rubor (redness), calor (temperature), dolor (pain) and
tumor (swelling), can allow for proper identification of infection sites.  As a clinician, it is important to present to
your patient all of the available options and their potential risks and
benefits so that they can participate in the choice.  The risk to benefit ratio of a hamstring
graft may not be a risk every patient is willing to take. Patients and athletes
do not like setbacks; therefore, they need to be well informed and we need to
take proper precautions to avoid infection.

Questions for
Discussion:  How can we reduce the risk
of infections after an ACL reconstruction? 
Why do you think there was a higher risk of infection using hamstring
autografts?  What do you think are the
pros and cons of using each of the different types of grafts?

By: Franki Gironda
By: Lisa Chinn and Jeffrey Driban


Patellar Tendon versus Hamstring ACL Autografts – The Value of Meta-Analyses and Systematic Reviews

Maletis GB, Inacio MC, Reynolds S, Desmond JL, Maletis MM, & Funahashi TT (2013). Incidence of postoperative anterior cruciate ligament reconstruction infections: graft choice makes a difference. The American Journal of Sports Medicine, 41 (8), 1780-5 PMID: 23749343