Assessing the Outcomes of Anterior Cruciate Ligament Reconstruction with or without the use of Antibiotic Solution in Graft Preparation: A Randomized Control Trial

Abstract

Background:

Reconstruction of ligament injuries, particularly the anterior cruciate ligament, is a widely accepted approach for restoring knee function in anterior cruciate ligament (ACL) deficiency; however, postoperative infections remain a serious complication. Presoaking grafts in antibiotic solutions offers protective benefits against infection by providing local antibiotic prophylaxis without affecting graft integrity. No high-quality RCTs in India have evaluated this infection prevention method.

Methodology:

In this prospective RCT at a tertiary center, 76 patients with complete ACL tears were allocated to presoaking of ACL grafts in either vancomycin solution (500 mg/100 mL saline for 10–15 min) in the experimental group or presoaking of ACL grafts in normal saline in the control group before implantation. A simple randomization technique using sealed opaque envelopes ensured unbiased allocation. The primary outcome was postoperative infection measured via C-reactive protein levels postoperatively to monitor the inflammatory response. Functional outcomes were assessed using the International Knee Documentation Committee (IKDC) and Lysholm Knee score at 6 months.

Results:

This study aims to evaluate the effectiveness of vancomycin presoaking of ACL grafts in reducing postoperative infection rates in patients undergoing ACLR. The vancomycin presoaked ACL grafts group (n = 38) had 0% infection versus 5.26% in the saline presoaked ACL grafts group (n = 38) (P = 0.152). No graft failures occurred in both groups. Mean IKDC scores were 87.02 ± 6.75 in the vancomycin presoaked grafts group versus 87.19 ± 6.24 in the saline presoaked grafts group (P = 0.838), and mean Lysholm scores were 83.68 ± 7.66 in the vancomycin presoaked grafts group versus 86.47 ± 6.38 in the saline presoaked grafts group (P > 0.05), respectively.

Conclusions:

Vancomycin presoaking of ACL grafts is safe and shows a trend towards lower infection risk without adverse effects on graft performance or recovery.

INTRODUCTION

The anterior cruciate ligament (ACL) is important in knee stability and is often injured during sporting activities or other physical activities through a change of direction or twisting of the body. In symptomatic ACL-deficient patients, particularly those who wish to resume high-activity levels, anterior cruciate ligament reconstruction (ACLR) is prescribed. We have, over the years, developed graft choices, methods of fixation, and after-surgery services to eliminate difficulties and maximize results. Even though surgical procedures and perioperative management improved and caused a deprivation in postoperative infection, especially surgical site infections, it remains a demanding complication characterized by devastating results such as graft failure, joint rigidity, and septic arthritis that may severely alter joint mechanics and long-term clinical outcomes. The origin of ACLR infection after the surgery is multifactorial. The operating environment, surgical instruments, intraoperative handling of the graft, and even the patient’s skin flora can contribute to contamination during autograft preparation. The ACL graft is especially prone to picking up contaminants and is sometimes called upon to be pretreated prior to implantation; research has revealed that even small amounts of contact with the environment may lead to bacterial colonization. At recommended levels of concentrations, vancomycin clears bacterial contamination with a lack of chondrotoxicity and a change in tendon material characteristics.[1]

Antibiotic solutions such as vancomycin have been tested to consider as a secondary preventive method of this occurrence by soaking the ACL graft prior to insertion. The graft can be soaked in vancomycin solution which is easy and cheap. Local prophylaxis can employ vancomycin that has a glycopeptide-based antibiotic which has been shown to be highly efficient in the treatment of Gram-positive bacteria, particularly Staphylococcus aureus and the coagulase-negative staphylococci. This is because the technique has attracted attention due to its possible potential in lowering infection levels and maintaining graft integrity.[2] A meta-analysis of 31,150 patients showed that all of the 49 vancomycin-presoaked hamstring autografts were infection-free compared with 0.74% with control grafts (P < 0.000001), and the overall infection rate of any graft type was reduced to 0. 01% by vancomycin presoaking.[3,4] Furthermore, usage of vancomycin does not pose any danger to graft integrity or elevate chances of arthrofibrosis because it remains bactericidal.[1] retrospective and observational studies have reported higher risk of septic arthritis in non presoaked grafts.[5]

A significant reduction in the incidence of postoperative infection rate with the use of vancomycin-presoaked grafts has prompted surgeons to adopt this practice, but there is a lack of large-scale prospective RCTs. A recent study supports the safety of vancomycin presoaking, leading to the absence of postoperative symptoms or infection rates in both groups: one receiving grafts soaked in vancomycin and the other receiving standard grafts without antibiotic soaking.[6] Yet on the other hand, a systematic review of 50 RCTs on ACLR reports that only a small proportion, about 10% of trials, demonstrate statistically significant differences between intervention and control groups for surgical techniques, with the remainder indicating comparable outcomes regardless of surgical variation.[2] Therefore, even small modifications in surgical protocol, such as graft soaking, warrant rigorous evaluation.

Although preliminary results are encouraging, inconsistencies in outcome definitions, dosing protocols, and follow-up durations across studies have limited the ability to generalize these findings. Preliminary observational studies and meta-analyses have suggested that presoaking ACL grafts in vancomycin can reduce infection rates to nearly zero without affecting biomechanical integrity or clinical outcomes. However, these findings require validation through high-quality RCTs to assess safety, efficacy, and reproducibility in diverse patient populations. This study was designed to fill that gap in the literature by conducting a prospective RCT to evaluate whether vancomycin presoaking of hamstring tendon grafts can significantly reduce postoperative infection rates following ACL reconstruction, compared to standard saline-presoaked grafts.

METHODOLOGY

Study design

This was a single-center, prospective, RCT conducted between September 2024 and March 2025. A total of 76 patients were randomly assigned to two groups to compare postoperative infection rates and functional outcomes following ACL reconstruction. Or else it can be written as “a picture of the graft used is shown in Figure 1.

Figure 1.

Graft preparation for anterior cruciate ligament reconstruction

Study setting

The study was conducted in the Orthopedic Department of Rajendra Institute of Medical Sciences (RIMS), Ranchi, a tertiary care center equipped with surgical, diagnostic, and rehabilitation facilities necessary for orthopedic procedures

Study duration

The trial commenced following ethical clearance and included all phases from patient recruitment and surgery to follow-up assessments at day 02, day 06, and 6 months postoperatively. The final follow-up visit and data collection were completed by March 2025.

Participants – inclusion/exclusion criteria

Inclusion criteria were adults (≥18 years) with complete ACL tears confirmed clinically and on magnetic resonance imaging.

Exclusion criteria included prior ACL surgery, multi-ligament injuries, active infections, or major comorbidities [Table 1].

Table 1.

Demographics of all study groups

Variables	Total (n=76), n (%)	Saline presoaked (n=38), n (%)	Vancomycin presoaked (n=38), n (%)	P
Age	27.6±8.9	28.4±7.5	27.2±7.2	0.43
Sex
Female	8 (10.5)	4 (10.5)	4 (10.5)	0.79
Male	68 (89.5)	34 (89.5)	34 (89.5)
BMI
Normal	70 (92.1)	35 (92.1)	35 (92.1)	0.31
Overweight	3 (3.9)	2 (5.3)	1 (2.6)
Underweight	1 (1.3)	1 (2.6)	0
Involved side
Right	41 (53.9)	21 (55.3)	20 (52.6)	0.902
Left	35 (46.1)	17 (44.7)	18 (47.4)

BMI=Body mass index

Study sampling

Simple randomization was performed using sealed opaque envelopes to assign patients into two groups.

Study sample size

Based on infection-free rates of 98%, 10% equivalence margin, 80% power, and 5% significance level, the required sample was 34 per group. Adjusting for 10% attrition, 38 patients were enrolled in each group.

Study groups

• Control: Grafts soaked in normal saline

• Intervention: Grafts soaked in vancomycin (500 mg in 100 mL saline) for 10–15 min before implantation.

Study parameters

The primary outcome was postoperative infection rate [Tables 2 and 3] measured using CRP levels. Secondary outcomes included graft failure and functional scores (International Knee Documentation Committee [IKDC], Lysholm) [Tables 4 and 5].

Table 2.

Infection rate

Group	Infection at day 02 (n)	Infection at day 06 (n)	Cumulative infection rate (%)	P
Vancomycin group	0	0	0	0.152
Saline group	2	0	5.26	>0.05

Table 3.

Complications other than infection

Group	Total complications up to 3 months (n)	Complication rate (%)
Vancomycin group	2	5.26
Saline group	3	7.89

Table 4.

Postoperative graft failure (3 months follow-up)

Group	Graft failures (n)	Failure rate (%)
Vancomycin group	0	0.00
Saline group	0	0.00

Table 5.

Functional outcomes and pain scores

Group	IKDC score (mean±SD)	Lysholm score (mean±SD)	P (IKDC)	P (Lysholm)
Vancomycin group	87.02±6.75	83.68±7.66	0.838	0.067
Saline group	87.19±6.24	86.47±6.38	(>0.05)	(>0.05)

IKDC=International Knee Documentation Committee, SD=Standard deviation

Study data collection

Demographics, surgical details, infection status, and follow-up IKDC and Lysholm scores were recorded using structured forms and compiled in Microsoft excel is a spreadsheet program in the Microsoft office suite.

Data analysis

Data were analyzed using jamovi statistical software jamovi, Version 2.4.8 (The jamovi Project, Sydney, Australia), The jamovi Project, Sydney, Australia. Continuous variables were reported as mean ± standard deviation, and categorical variables as percentages. Significance was set at P < 0.05.

Ethical considerations

The study was approved by the Institutional Ethics Committee. Informed consent was obtained from all patients. Confidentiality was maintained, and all patients received standard care throughout the study.

RESULTS

At both 1-week and 4-week follow-ups, no infections were observed in the antibiotic group, while the nonantibiotic group reported two infections (5.26%) [Table 2].

At 3 months, no new infections were identified in either group, confirming that early infections were confined to the nonantibiotic group and that no late-onset infections occurred.

The difference in infection rates was not statistically significant (P = 0.152).

The antibiotic group had 2 cases (5.26%) of minor complications, while the nonantibiotic group had 3 cases (7.89%) [Table 3]. These included stiffness and delayed wound healing but resolved with conservative management. No additional complications were reported at the 3-month mark in either group.

At 3 months, no participants from either group reported clinical signs or imaging-confirmed graft failure, indicating 100% graft integrity across both cohorts [Table 4].

By the 3-month follow-up, both groups achieved excellent functional recovery. No statistically significant difference in IKDC and Lysholm scores [Table 5]. Slight trend toward higher Lysholm scores in the nonantibiotic group, though not significant.

DISCUSSION

This RCT aimed to evaluate the effectiveness and safety of vancomycin antibiotic solution presoaking in ACL graft preparation compared to saline presoaking in an Indian cohort. While no infections were observed in the vancomycin group, the saline group reported a 5.26% infection rate. Although the difference was not statistically significant (P = 0.152), the findings align with global literature indicating a consistent trend toward reduced postoperative infections with vancomycin presoaking.

Our findings are congruent with large-scale data presented by Figueroa et al., (2021)[1] whose systematic review and meta-analysis of over 24,000 patients reported a 0.01% infection rate in the vancomycin group versus 0.8% in controls, translating to a 93% relative risk reduction. Similarly, Offerhaus et al. (2019)[2] observed a 0% infection rate in 853 patients receiving vancomycin-soaked grafts, as opposed to 2% in a control group. These studies, together with our data, reinforce the role of vancomycin presoaking as a promising preventive measure, particularly in settings where postoperative infection rates remain a concern.

Importantly, our results also suggest that vancomycin presoaking does not adversely affect graft performance or integration. Both groups had a similar result in terms of functional improvement measured using IKDC and Lysholm scores, and graft failure was not experienced in both groups. These findings conform with biomechanical evidence as published by Park et al., (2024)[8] whose findings revealed that vancomycin soaking does not have any negative effects on the tensile strength of the graft or its elongation properties during a cyclic load.

In addition, the absence of adverse side effects or allergic reactions in the vancomycin group showcases the safety of this treatment plan. This becomes particularly relevant in the Indian context, with the presence of multiple sterility procedures, a large number of surgical procedures and sometimes, restrictive follow-up postinfection control remains a significant issue. Although our study neglected the topic of functional differences between various types of grafts, the study conducted by Gupta et al. (2019)[7] offers additional information. Irrespective of the type of grafts, their findings have shown that the consistency of the surgical management and the technique, along with the potential application of presoaking techniques, have a significant influence on the indicators of recovery and its outcomes. Despite the positive outcomes of the study, there are some limitations of the study. First, the sample for this research might not be large enough to identify a significant variation of such rare events, such as infections.

Second, delayed graft failures or late-onset problems call for more protracted follow-up. At last, the microbiological examination of possible pollutants and the pharmacokinetics of vancomycin elution from grafts were not included but might be useful in upcoming research. The findings support the incorporation of vancomycin presoaking in ACL reconstruction protocols as a cost-effective, easily implementable method to reduce postoperative infections. Given the resource variability in Indian surgical settings, this method holds significant promise. Future multicentric RCTs with larger sample sizes and standardized postoperative protocols are warranted to establish definitive guidelines and evaluate long-term effects on graft longevity and patient-reported outcomes.

CONCLUSIONS

ACL grafts presoaked in vancomycin in this RCT had a 0% postoperative infection rate, while the nonantibiotic (saline) group saw a 5.26% rate; nevertheless, this difference was not statistically significant (P = 0.152). Antibiotic soaking did not jeopardise graft integrity or recovery, as evidenced by equivalent functional results, graft failure rates, and hospital stay durations between groups. Larger-scale research is necessary to validate overall efficacy, as these findings support the safety of antibiotic graft preparation and point to a possible trend toward infection reduction.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

PMJAY.