Introduction

Anterior cruciate ligament rupture is a frequent injury in sports and infection after reconstruction is rare (0.14-1.8%). Coagulase-negative staphylococci accounts 90% of the cases and is associated to contamination by the commensal bacteria of patient’s skin during graft preparation. Intravenous antibiotic prophylaxis and soaking of autografts with vancomycin (tendons are soaked into a compress that contains 100ml of NaCl mixed with 500mg of vancomycin for 10-15 min) have been applied in order to avoid infection after ACL reconstruction.

Purpose

To determine if hamstrings soaking with vancomycin leads to histopathological changes than can produce functional impairment in patient’s followup.

Methods

Assessment to the graft was made based on redundant tendon tissue from ACL reconstruction procedures of patients operated by the same surgeon maintaining a precise routine. Tendons collected during surgery were used and surplus segments were submitted to histopathological study and elastin impregnation. Two samples from each tendon of eighteen patients were analyzed, with and without vancomycin impregnation.

Results

This study included 18 patients. The mean age at surgery was 29 years old, 83.3% were male and 16.7% female. There were no cases (0%) of documented septic arthritis. Our results showed a considerable reinforcement of elastin wavy configuration after soaking with vancomycin and apparent retraction of surrounding tissues.

Conclusions

Hamstrings autografts structure is altered after vancomycin soaking. Histopathological adaptation described in this study might produce a decrease in tendon resistance to tensile forces that was not correlated with an increased risk of rupture. Future studies are needed to clarify vancomycin effects on graft integrity beyond infection concern and if the time and concentration of vancomycin interfere with the histopathologic properties. These findings raise concern about ACL preserved function after surgery and the actual vancomycin application.