Sports Medicine Research: In the Lab & In the Field: Anterior Cruciate Ligament Infections after Surgery (Sports Med Res)


Thursday, October 31, 2013

Anterior Cruciate Ligament Infections after Surgery

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

Maletis G, Inacio M, Reynolds S, Desmond J, Maletis M, Funahashi T. Am J Sports Med. 2013;41(8):1780-1785.

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.

Infection 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.

This 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?

Written By: Franki Gironda
Reviewed By: Lisa Chinn and Jeffrey Driban

Related Posts:
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


Richard Willy, PT, PhD, OCS said...

Interesting findings. 0.48% infection rate is lower than I would have expected.

Post a Comment

When you submit a comment please click 'Subscribe by Email" (just below the comments) or "Subscribe to: Post Comments (Atom)" (at the bottom of this page) if you would like to receive a notification when another comment has been submitted to this post.

Please note that if you are using Safari and have problems submitting comments you may need to go to your preferences (privacy tab) and stop blocking third party cookies. Sorry for any inconvenience this may pose.