Subdermal Betadine to Reduce Microbacterial Bioburden During Posterior Spinal Fusion
Phase: PHASE4
Conditions: Spinal Fusion
Sponsor: Akron Children's Hospital

 
 
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Subdermal Betadine to Reduce Microbacterial Bioburden During Posterior Spinal Fusion 
 
Principal Investigator: 
Lorena Floccari; MD; Department of Orthopedic Surgery   
Co-Investigators: 
 
Todd Ritzman; MD; Department of Orthopedic Surgery   
 
 
 
 
Richard Steiner, PhD; Steiner Statistics LLC 
 
 
 
 
Alexandria Rundell, BS; Rebecca D. Considine Research Institute 
 
 
 
 
Xiaotian Zheng, PhD, Medical Director of Microbiology 
 
Data Safety Monitor: 
Eric Robinette, MD; Infectious Disease 
 
 
 
 
 
 
 
Protocol version/date:  7/19/2024 
 
A.  Background and Significance 
 
Adolescent idiopathic scoliosis (AIS) occurs in approximately 1-3% of the population, 
while other underlying conditions are associated with scoliosis as well, such as 
neuromuscular disorders, congenital anomalies, and syndromes such as Marfan’s.1,2  
Large magnitude scoliosis curves are typically managed with posterior spinal fusion 
(PSF).   
 
Surgical site infections (SSI) are a leading cause of nosocomial infection that can 
contribute to significant patient morbidity or even mortality, negatively impact patient 
well-being and quality of life, and are a significant drain on health care resources.3,4    In 
patients undergoing PSF for scoliosis, SSI occur at rates of 1-2% in AIS patients, and in 
15-20% of higher risk populations, such as those with spinal deformity due to 
myelomeningocele and/or neuromuscular scoliosis.5   In addition to patient morbidity, 
SSI are a costly complication, with a mean additional cost of $154,537 per patient related 
to hospitalization and treatment of infection.6   Given that PSF is a relatively common 
procedure with >100 cases performed at Akron Children’s Hospital annually, we are 
continuously working towards process improvement for decreasing infection risk. 
 
One method to reduce SSI is perioperative skin preparation, as skin antiseptics decrease 
skin flora and kill superficial bacteria that otherwise could enter the wound and 
contribute to infection.  Prior studies have demonstrated that bacterial contamination 
from the patient’s skin is a major presumed source of postoperative infection, especially 
with an implanted biomaterial, as the bacteria can form a biofilm that protects the 
bacteria from the host cellular defense system and antibiotics.7-9  Skin antisepsis to 
decrease bacterial wound contamination has been shown to decrease incidence of SSI.10  
Thus, skin preparation is an important quality performance measure in the Centers for 
Disease Control and Prevention and Centers for Medicare and Medicaid initiated Surgical 

 
 
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Care Improvement Project.4,11 The most common skin antiseptics used in the operating 
room are chlorhexidine, iodine, and alcohol; however, there is no consensus in the 
literature regarding the most effective option, including for spine surgery.12    
 
Skin antiseptic solutions are applied to the skin prior to incision. However, while skin 
preparation is effective at reducing bioburden on the skin (3% microbial growth rate), 
there is a high rate of bacterial contamination at the dermal layer following skin incision 
(32% microbial growth), with contamination that remains abundant deeper in the spinal 
wound throughout the case.13  This is likely due to lack of deeper penetration of the 
topical skin preparation into the sweat glands or sebaceous glands, as evidenced in larger 
culture studies.14   Bacteria may then enter the wound upon making incision, resulting in 
contamination that could contribute to surgical site infection.  
 
SSI’s are always a substantial concern and therefore there is a need to investigate possible 
mitigation strategies. This project has the potential to have an immense impact by 
demonstrating a reduction in bacterial contamination by utilizing 10% povidone-iodine at 
the dermal layer of the skin.  
 
B.  Study Purpose and Objective(s) 
 
The goal of this project is to evaluate the efficacy of subdermal 10% povidone-iodine at 
reducing bacterial contamination from the dermal layer of skin during posterior spinal 
fusion. Our institution has standardized 2% chlorhexidine gluconate (CHG) and 70% 
isopropyl alcohol (IPA) solution (ChloraPrepTM) for orthopedic surgeries, including spine 
surgery, as alcohol-based skin preparations are widely considered standard of care.12   It 
is possible that a second application of surgical antisepsis with a topical povidone-iodine 
in the subdermal layer after making incision could decrease bacterial contamination that 
could enter the deeper wound and contribute to surgical site infection (SSI).   However, 
this has not been previously studied in this manner, so the effect of secondary wound 
preparation with subdermal povidone-iodine on bacterial contamination within the 
surgical wound is unknown.  
 
The purpose of this study is to evaluate the effect of this second preparation in terms of 
microbial bioburden reduction.  We hypothesize that povidone-iodine application in the 
dermal/ subdermal layer will significantly reduce microbial growth in the dermis and in 
the deeper surgical wound when compared to control patients.  We also hypothesize that 
reducing microbial contamination in the wound with subdermal povidone-iodine will 
directly reduce incidence of surgical site infection; however, this will require future 
studies with large populations given the relative rarity of this complication. 
 
The primary outcome of this study will be incidence of positive bacterial growth in 
several layers of the surgical wound:  the skin (after preparation with ChloraPrepTM), the 
subdermis (before and after application of povidone-iodine versus control with saline), 
and the deep surgical wound after exposure and before closure (Figure 1).   
 

 
 
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Secondary outcomes will be complications, including allergic reactions, contact 
dermatitis, surgical site infection and wound complications (Figure 1).  Tertiary outcomes 
are the effect of other patient and surgical variables on microbial growth, including age, 
gender, comorbidities, body mass index (BMI), operative time, blood loss, fusion levels, 
scoliosis etiology, curve type, curve magnitude (Cobb angle), use of prophylactic 
antibiotics, hospital length of stay, complications to include readmissions and 
reoperations (Figure 1). 
 
Figure 1. Objectives  
 
 
Objectives 
Primary 
To assess incidence of positive bacterial growth in five layers of the 
surgical wound. 
     1.      The skin, along the length of the planned incision 
     2.      The subdermis before application of povidone-iodine versus 
control with saline 
     3.      The subdermis after application of povidone-iodine versus 
control with saline) 
     4.      The deep surgical wound after exposure 
     5.      The deep surgical wound after all corrective maneuvers are 
complete, before closure 
Secondary To evaluate complications, including allergic reactions, contact 
dermatitis, surgical site infection and wound complications. 
Tertiary 
To determine the effect of other patient and surgical variables on 
microbial growth, including 
 
•         Age 
 
•         Gender 
 
•         Comorbidities 
 
•         Body mass index (BMI) 
 
•         Operative time 
 
•         Blood loss 
 
•         Fusion levels 
 
•         Scoliosis etiology 
 
•         Curve type 
 
•         Curve magnitude (Cobb angle) 
 
•         Use of prophylactic antibiotics 
 
•         Hospital length of stay 
 
•         Complications, including readmissions and 
reoperations.  
 

 
 
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C.  Human Subject Study Population 
• This will be a single institution randomized controlled trial and will include all English-
speaking patients ≤ 26 years old with scoliosis undergoing primary posterior spinal fusion 
of the thoracic and/or lumbar spine. We will exclude patients who have undergone prior 
spinal surgery, are undergoing procedures other than primary posterior spinal fusion of the 
thoracic and/or lumbar spine (cervical fusion, anterior surgery, growth-friendly 
instrumentation), or for any contraindication to povidone-iodine, including pregnancy, 
allergy, or prior treatment with radioiodine.12   
• The target enrollment for this study is 60 subjects. Patients who meet the inclusion 
criteria will be offered enrollment. Patients and their legal guardians will be informed of 
the nature of this study. The risks, benefits, advantages, and disadvantages of this study 
will be detailed with the patient and guardians, as a part of their routine pre-operative 
visit with their doctor. If the family wishes to enroll in the study, the informed consent 
process will be undertaken, and the patient will be enrolled.  
• We estimate a 75% rate of consent for patients who meet eligibility criteria. Given that 
there are >100 cases performed at Akron Children’s Hospital annually, our goal is to 
complete enrollment within 1 year of the start date. An enrollment log will be kept 
documenting rate of consent and if a patient declines, their reason for no consent.  
• Research material will include consent forms, electronic medical records, review of 
radiographs via PACS, and electronic data. As described in section D, five bacterial swab 
cultures will be obtained throughout the surgical procedure regardless of their treatment 
group and sent to the microbiology lab for processing, storage, and discarded per their 
standard protocols.  
• The following vulnerable populations will be included: 
 
☒Minors 
• Parent/guardians will sign the consent form, and assent will be obtained in 
children who are ≥10 years old, unless cognitively or decisionally-impaired 
☒Cognitively or decisionally impaired individuals 
• Cognitively or decisionally-impaired patients will be included if their 
parent/guardian is present and has the ability to understand and consent for the 
study.   
☒Students/employees of ACH 
• They will be included only if they meet all inclusion criteria with planned spinal 
surgery. 
☒Illiterate individuals 
• The surgeon and research coordinator will verbally explain the study, and an 
impartial witness will attest that the study was fully explained, and that the 
patient voluntarily agreed to participate. The patient signs in whatever way is 
customary for them (e.g., making their mark). The witness signs the consent 
on the witness line.  
☒Economically or educationally disadvantaged individuals 

 
 
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• Individuals who are economically disadvantaged are not being specifically 
targeted for this study but will be allowed to participate if they so choose. 
Compensation is not being offered, so this will not unduly influence 
participation in the research. 
 
D.  Research Design and Methods 
• This is a prospective, one site, randomized controlled trial.  Patients will be identified by 
ICD-10 diagnosis for scoliosis with a case request for posterior spinal fusion.  Eligible 
patients will be identified by the clinical research coordinators who typically review all 
planned spine surgeries for determining eligibility for spine registries (Figure 2).  
• Patients will be invited to participate at their preoperative orthopedic visit.  The study 
will be discussed by both the primary surgeon and the clinical research coordinator.  The 
risks, benefits, advantages, and disadvantages of this study will be detailed with the 
patient and family, as a part of their routine pre-operative visit with their doctor. If the 
family wishes to enroll in the study, the informed consent process will be undertaken, and 
the patient will be enrolled. 
• After enrollment, patients will be automatically randomized. Randomization schedules 
will be provided prior to initiation of the trial to balance treatment and control arms 
(Appendix A). The clinical research coordinator will provide the surgeon with a sealed 
envelope with their group determination (povidone-iodine vs control).  
• On the day of surgery, the surgeon will verbally confirm with the patient and family that 
they still wish to move forward with study participation.  A blank copy of the consent 
form will be available for review. 
• All female patients undergoing surgery (including patients not enrolled in a research 
study) undergo a pregnancy test on the morning of surgery according to standard surgical 
protocol.  If a patient enrolled in this study has a positive pregnancy test, they will be 
administratively withdrawn from the study. 
• Intraoperatively, patients will follow the standardized spine pathway, including standard 
antibiotics and skin preparation with isopropyl alcohol followed by ChloraPrepTM and 
sterile draping (Figure 3).   
• Bacterial cultures will be obtained with the use of an Eswab on the skin by rubbing along 
length of the planned incision, before standard placement of an antimicrobial adhesive 
drape known as a 3MTM IobandTM. An Eswab is a swab cleared by the FDA to aid as a 
transport system for your sample utilizing a plastic tube, containing an eluting liquid with 
a screw cap. All patients will be swabbed in the same fashion for each Eswab to assure 
consistency across patients.  
• Prior studies have demonstrated no difference in culture positivity based on the level of 
the spine (cephalad/caudal thoracic and/or lumbar spine).7 Therefore, each swab will be 
taken along the entirety of the posterior spinal incision and accordingly swabs may vary 
slightly in levels as each patients’ levels will be individually determined case by based 
upon the planned thoracic and/or lumbar fusion levels. 
• The surgeon will make incision with a scalpel and then obtain a bacterial culture in the 
subdermal layer in all patients by rubbing an Eswab along the subdermis. 
• A nurse will open the sealed envelope. At this time the surgeon will be notified which 

 
 
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group the patient is in and the surgeon will proceed accordingly. If patients were 
randomized to the povidone-iodine group, then a single-use sealed packet of 10% 
povidone-iodine swabs will be opened via standard sterile technique.  Three 10% 
povidone-iodine swabs are provided in each packet, and thus all three will be utilized for 
this study according to manufacturer recommendations.  If patients are in the control 
group, then sterile swabs will be provided for soaking in sterile saline as a sham.  Three 
saline swabs will be utilized so as to match the application technique as used with 
povidone-iodine swabs. 
• Patients who were randomized to the povidone-iodine group will then have three topical 
applications of 10% povidone-iodine along the length of the subdermis, using each of the 
3 swab sticks provided from the sterile single-use packet. Following the 10% povidone-
iodine application, the solution will be allowed to dry at least three minutes.  Patients 
who were randomized to the control group will then have three applications of sterile 
saline along the length of the subdermis, using each of the 3 swab sticks soaked in sterile 
saline.  
• Following application of either 10% povidone-iodine or saline and waiting 3 minutes for 
drying time, an additional culture will be obtained by rubbing another Eswab along the 
incision in the subdermis. 
• Surgical exposure will proceed in all patients, and an additional culture will be obtained 
with an Eswab along the length of the deep wound after exposure is complete, and a final 
culture along the length of the deep wound just prior to wound closure. 
• All Eswabs will be labeled and sent to the microbiology lab for cultures.  Culture growth 
will be recorded after final results have been reported. To mitigate competing interest, the 
investigators or surgeons delivering patient care, administering the treatment or control, 
and obtaining the bacterial culture swabs will be blind prior to surgery and only to the 
culture results. Each of the five samples per patient will receive a separate sample ID 
from the biorepository blinding the investigators or surgeons delivering patient care to the 
culture results only.  
• Routine postoperative care of patients will not change according to culture results, with 
standard-of-care prophylactic antibiotic dosing. Therefore, routine antibiotics will not be 
extended or changed from standard prophylactic protocol unless there is otherwise a 
clinical indication, such as for any clinical evidence of infection (superficial or deep), as 
per standard of care and clinician discretion.  Patients will be closely followed via the 
standard postoperative spine clinical schedule as noted in Figure 2.   
• Research coordinators will not be blinded to the results as they will provide and 
document data, sources of data for adherence metrics (the electronic medical record), 
screening, and enrollment logs when needed.  
• All spine surgeons will be included for participation in this study, including the primary 
and co-investigator.  It is not possible to blind surgeons to the treatment group, given that 
povidone-iodine is administered into the surgical wound intraoperatively.  This must be 
performed by the treating surgeon, as it would not be considered reasonable for the 
surgeon to exit the operating room for blinding, and/or for a non-surgeon to perform this 
procedure on an open wound intraoperatively.  Therefore, surgeons will not be blinded to 
the treatment group, but all surgeons will be blinded to culture results of both control and 
test patients to mitigate risk of bias of competing interests.  

 
 
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• The duration of participation for patients will be only on the surgical day, though we will 
prospectively follow patients clinically to report postoperative course, including 
occurrence of any complications. 
 
Figure 2. Schedule of Activities  
 
 
 
 
 
 
 
 
 
 

 
 
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Figure 3. Intraoperative Schema 
 
 
 
 
 

 
 
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Study Variables.  For patients meeting inclusion criteria, variables to be collected and 
analyzed include, but are not limited to, those listed below.   
• Demographic information – will be reviewed to address tertiary outcome of 
association between patient characteristics and positive microbial growth 
- 
Dates needed to calculate age 
- 
Gender 
- 
Height and weight for BMI 
- 
Comorbidities 
- 
Allergies 
- 
Scoliosis etiology 
• Curvature characteristics- will be reviewed to address tertiary outcome of association 
between curve characteristics and positive microbial growth 
- 
Radiographic curve classification (Lenke type) 
- 
Coronal curve magnitude (Cobb angle) 
- 
Thoracic kyphosis magnitude 
• Surgical treatment characteristics- will be reviewed to address tertiary outcome of 
association between surgical variables and positive microbial growth 
- 
Prophylactic antibiotics 
- 
Vertebral fusion levels (length of fusion) 
- 
Estimated blood loss 
- 
Operative time 
- 
Intra- and post-operative prophylactic antibiotic regimen 
- 
Intraoperative complications (i.e. Neurologic, etc.) 
- 
Length of hospital admission 
• Complications- will be reviewed to address secondary outcome of complications 
associated with povidone-iodine application. 
- 
Allergic reactions (i.e. contact dermatitis) 
- 
Surgical site infections 
- 
Postoperative complications (i.e. poor wound healing, infection, severe pain, 
etc.) 
- 
Readmissions/ reoperations 
 
• The following elements of PHI will be accessed and/or collected: 
 
☒ Names 
 
☒ All elements of dates (except year) for dates directly related to an individual, including 
birth date, admission date, discharge date, date of death 
 
☒ Medical record numbers 
 
 
 
 

 
 
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E.  Consent, Privacy and Confidentiality 
• All investigators and study team members will meet Akron Children’s IRB human research 
subject protection certification requirements. An investigator or research associate will 
invite parents and children meeting inclusion criteria to learn about study participation. 
Once the prospective parent or legal guardian expresses interest in study participation, the 
study team member will begin the informed consent/assent process using the IRB-approved 
form. After the parent/legal guardian reads the informed consent document, the study team 
member will solicit and answer all questions or concerns that parents raise. When the 
parent/legal guardian expresses satisfaction with the study team member’s explanations 
and has no further questions, the study team member will reiterate all consent form content. 
The parent/legal guardian may then sign the informed consent document indicating a 
commitment to participate. As noted above, the same communication process will apply to 
children and adolescents requiring informed assent. 
• We request a waiver of HIPAA authorization for screening purposes, as the use or 
disclosure of protected health information involves no more than a minimal risk to the 
privacy of individuals.  All electronic data will be stored on a password-protected 
institutional network drive, and any hard data will be stored in a locked filing cabinet in 
the principal investigator’s work office.  Once enrollment is complete, patient identifiers 
will be removed and replaced with a unique identifying number.  The protected health 
information will not be reused or disclosed to any other person or entity, except as 
required by law.   Access to and use of the protected health information is necessary to 
screen patients, as patients will be identified from their procedural codes, and their PHI 
will be utilized to identify their medical record.  This could not practicably be conducted 
without the waiver as we would be unable to accurately identify patients’ medical records 
to ensure accuracy. 
• This study involves Protected Health Information (PHI). Authorization is obtained by a 
(Consent and Assent) Authorization Document and data used is a limited data set. Data 
collected will be a limited data set, specifically the only PHI utilized will be dates and 
MRN. 
• The Eswabs will be managed according to standard microbacterial lab protocols: the 
Eswabs will be stored and refrigerated for 3 days after receiving the specimen.  
Following this time frame the specimen will be discarded.  Any aerobic organism 
reported to the patient’s chart is held at room temperature for 5 days before disposal, 
while anerobic organisms are frozen upon recovery and stored at-70C in the laboratory 
for approximately 2 years according to standard microbiology laboratory protocol. 
Disposal of all specimens and isolates is done as regulated medical waste to ensure 
proper control of biohazards and secure destruction of PHI that may be on labels. 
 
• All electronic data will be stored on a password-protected institutional network drive, and 
any hard data will be stored in a locked filing cabinet. The enrollment log and linking log 
(to connect subject and the subject’s unique identifying number) with patient identifiers 
will be kept separately. Information will not be disclosed to anyone outside of the research 
study.  Once data abstraction is complete, the patient identifiers and linking log will be 
destroyed. The protected health information will not be reused or disclosed to any other 
person or entity, except as required by law. 

 
 
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F.  Potential Risks/Benefits 
 
• Povidone-iodine is an over-the-counter topical antiseptic that is FDA approved in 
pediatric and adult patients.  It is considered safe and effective to reduce the number of 
bacteria on the skin prior to surgery.  Therefore, it is widely utilized across multiple 
healthcare settings as an antiseptic with low risks.  In addition to use as a topical surgical 
skin antiseptic, povidone-iodine can also be utilized within spinal wounds, with prior 
studies demonstrating lower rates of infection in pediatric deformity surgery when used 
as a wound irrigant.15  Further, 10% povidone-iodine paint is commonly utilized for 
application directly onto the skin, subdermis, and deeper wound tissue in the setting of an 
open fracture when alcohol-based solutions are typically avoided due to potential for 
tissue toxicity.16   
• Allergic or hypersensitivity reaction can rarely occur.17 Allergic contact dermatitis (type-
IV hypersensitivity reaction) is poorly described despite widespread use of this product, 
with prior studies demonstrating a prevalence of 0.04% - 0.4%.17 One study reported 2 
cases of allergic contact dermatitis in 5000 patients in whom a skin preparation solution 
was utilized (0.04%)18, while a more recent study demonstrated a 0.4% incidence on 
formal patch testing, as recruited from a patch-testing clinic.19   Recent literature has 
supported the safety of povidone-iodine even in patients with shellfish allergy, but should 
only be avoided in the setting of true iodine allergy confirmed by patch testing.17  Other 
contraindication to povidone-iodine use include comorbidity such as hyperthyroidism or 
other thyroid disease after treatment with radioiodine.12   
• Type-1 allergic reactions leading to anaphylaxis resulting from povidone-iodine exposure 
is exceedingly rare, though could result in anaphylactic shock which can be life-
threatening.20  This risk will be minimized by asking patients about allergy to povidone-
iodine at time of consent.  While the risk of previously undiagnosed allergy cannot be 
completely avoided, it is exceedingly rare.  
• Another potential risk to participants is loss of patient confidentiality through their data 
being accessed and included as part of this study.  However, the risk of invasion of privacy 
is no greater than would occur in the physician reviewing their records in normal clinical 
care.  This risk will be minimized by taking precautions as detailed in Section E above. 
• Participation in this surgery may slightly prolong surgery.  We anticipate that obtaining 
each culture and the application of the povidone-iodine will each take about 10-20 seconds, 
so the total duration for study participation should be less than 2 minutes of additional time 
under anesthesia.   
• The potential benefit of povidone-iodine as an antiseptic in the dermal layer could 
directly benefit the patient by reducing bacterial burden and decreasing risk of surgical 
site infection, which is one of the most common risks of spinal fusion surgery.  This 
study also has the potential widespread benefit to others by improving methods of 
reducing the burden of SSI in all surgical wounds with potential applications beyond 
spinal fusion.  Therefore, it is felt that the potential benefits outweigh the risks, given that 
povidone-iodine is widely accepted by the FDA and across health-care institutions 
(including our own) as a safe antiseptic for use in routine patient care.   
 
 

 
 
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G.  Statistical Methods 
• This is a repeated measures study design with one repeated factor, Location/Condition 
(skin, subdermal before treatment, subdermal after treatment, deep wound immediately 
after exposure, and deep wound just before closure) and one grouping factor, Treatment 
(test, control). The test treatment is povidone-iodine; the control treatment is saline. In 
both treatment groups, there will be five measurements per patient at different locations 
or under different conditions. Each swab will be analyzed for presence/absence of 
bacteria. For each location/condition the outcome measure is the percentage of patients 
with positive bacteria cultures.  
• Comparisons among locations/conditions and between treatment groups will be 
conducted in a generalized linear mixed model (GLMM) framework with a binomial 
distribution and a logit link function. Locations/conditions, treatments, and their 
interaction will be assessed and multiple comparisons among locations/conditions will be 
conducted as appropriate. 
• Sample size determination for GLMMs is an open question in statistical research. 
Methods that have been proposed are extremely complex, involving simulations, and are 
difficult to implement. For this study, we focus the power analysis on three comparisons 
that are of primary interest. 
o First, we will compare the percentage of patients with positive bacteria cultures in 
the subdermal layer of each treatment group before application of the treatment 
vs. after treatment. For this, McNemar’s test of marginal homogeneity is 
appropriate. Based on previous research, we estimate that about 32% of patients 
will have bacteria present before treatment with povidone-iodine and about 3% 
will be positive after treatment. Under these conditions, the power for a one-tailed 
test at the 0.05 level of significance would be between 86% and 88% for n=30 
patients in the test group, depending on the correlation of positive bacterial 
growth between the before and after measures. 
o The second comparison will be the percentage of patients with positive bacteria 
cultures in the deep wound at exposure in the povidone-iodine group vs. the 
control group. For this, a z-test for the equality of independent proportions is 
appropriate. From previous research, we estimate that about 17% of patients in the 
control group will have bacteria present in the deep wound and about 1.6% will 
be positive in the povidone-iodine group. For this comparison, the optimal sample 
size allocation is n=30 patients in the test treatment group and n=30 patients in the 
control group. With this allocation, a one-tailed test at the 0.05 level of 
significance would have 69% power.    
o The third comparison will be the percentage of patients with positive bacteria 
cultures in the deep wound at just before closure in the povidone-iodine group vs. 
the control group. Once again, a z-test for the equality of independent proportions 
is appropriate. From previous research, we estimate that about 40% of patients in 
the control group will have bacteria present in the deep wound before closure and 
about 4% will be positive in the povidone-iodine group. For n=30 patients in the 
test treatment group, n=30 patients in the control group, and a one-tailed test at 
the 0.05 level of significance the power would be 98%. 

 
 
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H.  Data and Safety Monitoring    
• This study poses minimal risk to the participant.  The only differences from standard of 
care protocol for spinal fusion includes: 
o Performing cultures with a swab.  This does not require removal of patient tissue 
and is considered minimal risk. 
o Application of povidone-iodine versus saline.  While povidone-iodine has not been 
evaluated for this specific purpose, povidone-iodine is FDA approved in children, 
available over-the-counter, and is already widely utilized at our institution as a 
topical antiseptic, including for surgical skin preparation of open wound. 
• Clinical site monitoring is conducted to ensure that the rights and well-being of trial 
participants are protected, that the reported trial data are accurate, complete, and verifiable. 
Akron Children’s Hospital Regulatory Compliance Specialists will monitor regulatory 
compliance, including processes for screening, consent, enrollment, and documentation. 
This will be done after the first 10 patients enrolled, 6 months after the start of the study 
and after the completion of enrollment.  Data collection is the responsibility of the study 
staff at the site under the supervision of the site investigator, and the PI will personally 
review and verify data for accuracy and completeness, legibility, and timeliness of the data 
reported.  All source documents will be completed in a neat, legible manner to ensure 
accurate interpretation of data. The Data Management Specialist will monitor the data after 
the first 10 patients are enrolled, 6 months after the study start date and at the completion 
of the study. 100% of the data collected will be reviewed to that date to ensure that data 
are accurate, complete, and verifiable. 
• The data safety monitor, Dr. Eric Robinette, will review the documented data by the 
study staff and monitor for any relationship between positive cultures every and SSI, if 
any, every 10 patients. If any relationship is noted, the data safety monitor will be report 
as necessary in the Adverse Event Log and notify all investigators. The data safety 
monitor and investigators will consider whether there is a reasonable possibility that the 
study intervention caused the event, whether there is potential harm by not treating a 
positive study culture, and/or if the study needs redesigned or discontinued. 
 
 
I.  Literature Cited 
 
1. 
Dunn J, Henrikson NB, Morrison CC, Blasi PR, Nguyen M, Lin JS. Screening for 
Adolescent Idiopathic Scoliosis: Evidence Report and Systematic Review for the US 
Preventive Services Task Force. JAMA. 2018;319(2):173-187. 
2. 
Konieczny MR, Senyurt H, Krauspe R. Epidemiology of adolescent idiopathic scoliosis. J 
Child Orthop. 2013;7(1):3-9. 
3. 
Badia JM, Casey AL, Petrosillo N, Hudson PM, Mitchell SA, Crosby C. Impact of surgical 
site infection on healthcare costs and patient outcomes: a systematic review in six European 
countries. J Hosp Infect. 2017;96(1):1-15. 
4. 
Berrios-Torres SI, Umscheid CA, Bratzler DW, et al. Centers for Disease Control and 
Prevention Guideline for the Prevention of Surgical Site Infection, 2017. JAMA Surg. 
2017;152(8):784-791. 

 
 
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5. 
Floccari LV, Milbrandt TA. Surgical Site Infections After Pediatric Spine Surgery. Orthop 
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