Impact on Tourniquet Use on Functional Outcomes and Complications After TKA
Phase: NA
Conditions: Arthritis Knee
Sponsor: Washington University School of Medicine

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1/10 
Human Research Protection Office  
Box 8089 
(314)633-7400 
Fax (314)367-3041 
 
 
Title:  
Impact of Tourniquet Use on Functional Outcomes and Complications after TKA 
Principal Investigator:  
Robert L. Barrack, MD 
 
 
Co-Investigators: 
Ryan M. Nunley, MD 
Charles Lawrie, MD 
Marcie Hayes, PT, DPT, MSCI 
Richard Rames, MD 
 
OVERVIEW 
 
Background information: 
  
Functional recovery after total knee arthroplasty (TKA) has seen dramatic improvement over the 
past 20 years through advances in surgical technique, implant design, perioperative pain 
management strategies, and physical therapy protocols. Tourniquet use during TKA, however, 
remains controversial due to conflicting reports in the literature on these benefits and risks of its 
use. Reported advantages of tourniquet use include improved visualization of the surgical field and 
decreased intraoperative blood loss. (Austin, 2019) Reported disadvantages of tourniquet use 
include increased postoperative pain and slower functional recovery as a direct result of the 
pressure of the tourniquet on the thigh during the procedure. (Ejaz 2014, Harsten 2015) 
Traditionally with tourniquet use during TKA, the limb is exsanguinated and the tourniquet is raised 
to a fixed, pressure at the beginning of the case, typically 250mmHg to 350mmHg, and let down 
after closure. A novel tourniquet design that adjusts the tourniquet pressure in real-time based on 
intraoperative patient blood pressure measurements. This design may allow for the tourniquet to be 
inflated at a lower mean pressure while still maintaining efficacy. 
A prospective study comparing total blood loss, pain and functional recovery after TKA 
using this novel tourniquet design, design (Zimmer A.T.S.® 4000TS Automatic Tourniquet System, 
with disposable contour cuffs) and TKA without tourniquet would further the current literature. Total 
blood loss will be calculated by previously validated methods. Pain and functional recovery will be 
closely monitored throughout the postoperative period using a patient wearable activity tracker 
(FitBit Inspire HR) and a smartphone-based patient engagement platform with integrated digital 

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surveys paired with smart-brace based home PT assessments (FocusMotion).Pain and functional 
recovery will be closely monitored throughout the postoperative period using a patient wearable 
activity tracker (FitBit Inspire HR) and a smartphone-based patient engagement platform with 
integrated digital surveys paired with smart-brace based home PT assessments (FocusMotion). 
Applying this technology to the proposed study can help identify problematic pain that is not 
appreciable during admission; given the fact that markers of inflammation and myocyte damage 
increase over time until at least post-operative day 3, it is possible that TKAs performed under 
tourniquet may have pain and narcotic requirements not appreciated with short-stay admissions 
(Huang 2014). The proposed study will further the literature on pain and narcotic use in the early 
time period after TKA, and will help identify if tourniquet has an effect on these variables. 
Furthermore, sleep quality is a component of functional recovery and is correlated with pain. Knee 
osteoarthritis affects general quality of life by increasing sleep disturbance and nighttime wakening, 
and this is correlated with the pre-operative radiographic severity of disease (Sasaki, 2014). Sleep 
quality is affected in the immediate post-operative period after TKA as well, but improves by 3-6 
months post-operatively (Chen, 2016). The proposed study would be the largest prospective study 
investigating the effect of TKA on pain and sleep quality, as well as being the first to investigate 
tourniquet use as a factor affecting sleep quality and pain. The proposed study would be the first to 
collect both subjective and objective data on the subject, using validated survey measurements as 
well as the data collected by the Fitbit Inspire HR device. 
Research objectives:  
The purpose of this study is to determine the effect of novel pressure-regulating tourniquet 
use on pain, functional recovery, sleep and total blood loss following total knee arthroplasty. 
Specific Aim 1: Our primary aim is to determine the effect of tourniquet use on pain after TKA.  Pain 
levels and oral analgesic requirements will be assessed daily using the FocusMotion remote patient 
monitoring platform. 
Specific Aim 2: Secondary aim to determine the effect of tourniquet use on functional 
recovery after TKA. To do so, we will using a combination of standardized clinical assessments 
performed by physical therapy preoperatively and at 3 months postoperatively, as well as 
assessments with patient reported outcome surveys and functional assessments at regular 
intervals using the FocusMotion remote patient monitoring and virtual physical therapy platform. 
Specific Aim 3: The third aim is to investigate sleep quality in the post-operative period after TKA 
with and without tourniquet use. We will apply both subjective measurements using the Pittsburgh 
Sleep Quality Index (PSQI) as well as sleep quality data as collected by the Fitbit HR. 
Specific Aim 4: The fourth aim is to determine the effect of tourniquet use on total calculated blood 
loss after total knee arthroplasty. Hemoglobin dilution will be utilized to determine calculated blood 
loss using a validated methodology. 

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Potential Contribution: This study would give us a better understanding of the effect of a pressure 
auto-regulating tourniquet on pain, functional recovery sleep, and blood loss after total knee 
arthroplasty. 
METHODS 
Timeline: 3 years (2 year of prospective enrollment, 3 months years of follow-up for all participants, 
approx. 9 months of data analysis) 
 
Inclusion/Exclusion criteria: The Principal Investigator (PI) will independently review all cases to 
confirm study eligibility for each patient. The following inclusion and exclusion criteria will be used to 
determine patient eligibility. 
 
Inclusion criteria: 
1. Age 18 and up 
2. Primary unilateral TKA 
3. BMI<45 
4. Primary diagnosis of osteoarthritis 
5. Patient has a iOS or Android smartphone capable of running FitBit and FocusMotion 
applications  
 
Exclusion criteria: 
1. Revision TKA 
2. Bilateral TKA 
 
3. Pregnancy 
4. Prisoners 
5. Pre-existing functionally-limiting neurologic disorder 
6. Narcotic dependence, defined as oxycodone/hydrocodone use >5days/week 
7. History of unprovoked VTE/PE  
8. Inability to complete baseline functional testing 
 
Recruitment: We will be recruiting patients from the clinical practices of Dr. Ryan Nunley, Dr. Robert 
Barrack and Dr. Charles Lawrie.  
 
Design: The proposed study is a prospective, single blinded, randomized clinical trial with 2 study 
groups 
 
 
For purposes of randomization, patients will be randomized into one of two groups tourniquet or no 
tourniquet, stratified by surgeon,using randomization sequences generated a priori using a 
computerized formal probability model with a block design and 1:1:1:1 allocation ratio.  Patients will 

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be blinded to study group membership. As a result of the blocking, the desired allocation ratio will be 
maintained at periodic intervals throughout the recruitment process.  The randomization 
sequences will be uploaded to REDCap so that allocations will be elicited using the REDCap 
randomization module in the immediate pre-operative period to minimize loss to follow-up. 
  
Number of participants:  
A pre-hoc power analysis for the primary outcome measure of VAS pain score was performed. A 
medium effect size of 0.5, power of 0.8, and alpha error of 0.05 were used for the analysis. With 
these assumptions, 128 patients were required to be enrolled in the study. With the dropout rate 
assumed to be 10%, 144 patients will be enrolled in the study. 
 
Data collection:  
Data collection will be done preoperatively, intraoperatively, 4 weeks post operatively, and at 12 
weeks post operatively and at 1 year postoperatively. The data will be analyzed by site staff. All data 
to be collected can be found in tables 1-8.  
 
All procedures will be performed by three surgeons (R.B., R.N., C.L) within a single institution at one 
site (Barnes Jewish West County and Progress West Hospital).  
All participants will undergo standard admission and pre-operative procedure for primary total knee 
arthroplasty per institution protocol. Participants will be admitted to hospital on day of surgery for 
elective procedure. Spinal anaesthesia will be placed in pre-op holding area per regional 
anaesthesia team. Participants will be positioned in standard supine position. Per operative 
protocol each patient will undergo standard prep and drape. There will be no application of 
tourniquet for those randomized to no-tourniquet arm. If tourniquet is to be used, it will be applied 
after induction and will be deflated after incision closure. Maximum tourniquet time will be 120 
mintues, TKA implant choice will be made based on surgeon preference. Transexamic acid will be 
given 1g IV prior to incision and 1g IV at end of case. The procedure for all participants will be via 
midvastus approach to the knee. At the end of the procedure, all patients will receive standard 
ipericapsular injection of 30mL 0.25% Marcaine with epinephrine and 30mL toradol prior to closure. 
PT treatment and evaluation will take place on day of surgery post-operative day one prior to 
discharge. All patients will be placed on Aspirin EC 325mg BID for VTE prophylaxis. Pain 
medications will be standardized during admission, and an uncontrolled pain protocol will be 
available for implementation at physician discretion; see Tables 1 and 2) The final set of standard 
blood labs will be drawn at midnight. Discharge medications will be standard(Table 3)., Patients will 
be contacted at 1 week post-operatively to evaluate clinical progress, general concerns and 
compliance with study protocols, including use of the Fitbit HR platform and FocusMotion platforms. 

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Participants will be scheduled for a standard clinical visit at 4 weeks.  
Participants will undergo final clinical evaluation at 3 months post-operatively with a PT visit and 
phone call from the research team as well as a final questionnaire about their experience with the 
app and Fitbit and knee brace which will be completed by paper, phone, or electronically. 
Fitbit Activity Tracker and Focus Motion knee brace apps 
During the pre-operative arthroplasty class, participants in the study will be set-up with a FitBit 
wrist-based activity tracker and FocusMotion knee brace and the appropriate software. Participants 
will be instructed to use the device in the 2 weeks prior to undergoing surgery, to gather baseline 
data on narcotic use, pain, use of assistive device and sleep quality. They will continue to use the 
devices for 3 months postoperatively(Table 7).  
Subject Payment 
Honorarium of $100 provided at 3 months  following completion of 3 month evaluation. Participants 
will be gifted the Fitbit Inspire HR and the FocusMotion smart-brace and platform and given an 
honorarium of $50  for completion of the 1 year app based survey. 
 
 
Participants Lost to follow-up: Some participants will not return for follow-up at the required 
intervals.  A member of the research team shall contact non-respondent participants using phone 
calls, regular mail, e-mail, certified letters, or other means to urge participants to return for clinic 
follow-up or ascertain if a participant has moved, died, or otherwise become lost to follow-up.  The 
following flow chart identifies the steps for attempts to locate lost participants.  These actions, 
along with any other options available to the site, should be followed to exhaust all reasonable 
means in locating lost participants.  These actions should be documented in the participant’s 
records and may be performed concurrently or in parallel. 
 
Phone call to last known number  Contact  Follow-up with participant 
 
No Contact 
 
Phone call to other numbers (spouse, relative, etc.)  Contact  Follow-up with participant 
 
No Contact 
Note: There will be a minimum of 3 calls to different numbers 
 
Mail letter to last known patient address  Contact  Follow-up with participant 
 
No Contact 
 

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Mail letter to secondary addresses  Contact  Follow-up with participant 
 
No Contact 
 
Mail “certified” type of letter to last address and any secondary address  Contact  Follow-up 
with participant 
 
No Contact 
 
Social Security Death Index to determine if participant has died  Confirm death 
 
Not Confirmed 
 
End attempts. 
 
INFORMED CONSENT 
 
Enrollment and consent will begin in the clinics of Dr. Ryan Nunley, Dr. Robert Barrack and Dr. 
Charles Lawrie, and will be the same for both study groups. The consent process will occur by one 
of the following means:  
 
1) The study coordinator will meet with each potentially eligible participant to review the study 
requirements (including additional screening for eligibility) and answer any questions the patient 
may have.  
 
If the patient has any clinical questions that cannot be answered by the study coordinator they will 
be answered by the physician or the physician's nurse. The patient will have the opportunity to 
review the consent form, discuss with family/friends, and do his/her own research on the subject if 
desired. Qualified patients who agree to participate in the study will be required to sign an Informed 
Consent Document. Valid enrollment is not granted until after surgery, once it has been verified that 
the participant qualifies for total knee replacement.  
 
2) The consent discussion and review of the Informed Consent Document may occur over the 
phone. In this case, the study coordinator will call the patient to present the study to the participant 
and gauge interest in participation. If the patient expresses interest in participation, the study 
coordinator will e-mail, mail or fax the Informed Consent Document to the participant. The patient 
will be given the opportunity to ask questions. If the patient has any research questions beyond the 
scope of the study coordinator, arrangements will be made for the participant to speak with the 
applicable member of the research team, including the PI. After review of the Informed Consent 
Document, the participant will sign the applicable sections of the Informed Consent Document and 
email, mail or fax the consent for back to the study coordinator. The Informed Consent Document 
will be signed by the consenting study coordinator upon receipt. Valid enrollment is not granted until 

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after surgery.    
 
PROCEDURES FOR MAINTAINING CONFIDENTIALITY 
 
Data Security: Hard copies of patient questionnaires and CRFs will be stored in individual patient 
binders. The binders will be kept in a locked filing cabinet in an office that has password protected 
access and is locked when not in use.  
 
Data collected on questionnaires and CRFs will be entered into electronic databases for analysis 
and tracking. These databases are on a secure server and can only be accessed by authorized 
research team members. There is no intention that the electronic records will be transported. We 
will not use laptops/jump drives/CD/DVDs to store, analyze, or input this data.  
 
For data collected by the Fitbit platform including health monitoring and app-generated data, 
pre-assigned study ID numbers and anonymous email addresses will be used for all 
patient-reported and patient-generated data collection and transmission. No ePHI is seen or 
handled by the smartphone application or its data collection platform. The electronic key will be 
available only to the study team, not the mobile health platform or app developers.   
 
 
De-identification of Data: All information will be collected by the research team in a confidential 
manner. PHI will be de-identified. All data will be entered into a master database that is password 
and security protected. Only members of the research team will be able to access information on 
study participants. Electronic key linking participant to data will be kept on a secured, 
password-protected network. All electronic information will be encrypted and stored in a 
password-protected database. All research files will be kept in a secure, locked location which can 
only be accessed by the study team. Once all manuscript submission is complete, all study 
documents, including the master list, will be retained for seven years after close of the study. 
 
ASSESSMENT OF RISKS AND BENEFITS 
 
There is a slight risk that patients may feel a small amount of psychological discomfort answering 
the questionnaires.  
 
In addition there is the risk of breach of confidentiality. 
 
Benefits: Participants will receive no direct medical benefit from study participation. However, 
this prospective study is the first to investigate tourniquet use as a factor affecting sleep quality 
and pain by collecting both subjective and objective data on the subject that is not be 
appreciable during admission. Furthermore, the study device design of adjusting tourniquet 
pressure in real-time based on intra-operative patient data measurements may allow for the 
tourniquet to be inflated at a lower mean pressure while still maintaining efficacy. 

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G1. Tables  
Table 1: Post-operative pain protocol  
Medication 
Dose and Route 
Timing 
PRN 
Percocet 5mg/325mg 
1-2 tablets PO  
Q6 hours 
Yes 
Toradol 
30mg IV 
Q6 hours 
No 
Morphine 
2-4 mg IV 
Q4 hours 
Yes 
*Toradol withheld in patients with sulfa allergy 
Table 2: Discharge medication protocol 
Medication 
Dose and Route 
Timing 
Duration/PRN 
Aspirin  
325mg PO  
BID 
 6 weeks 
Percocet 5mg/325mg 
1-2 tablets PO  
Q6 hours 
PRN 
Celebrex* 
200mg PO 
BID 
5 days 
Senna-docusate 
8.6mg/50mg PO 
BID 
PRN 
*Celebrex withheld in patients with sulfa allergy 
Table 3: Pre-operative data within 4 weeks of procedure 
Test 
Unit 
Collected by 
Knee circumference 
cm 
PT measurement 
Passive Knee ROM 
degrees 
PT measurement 
Active Knee ROM 
degrees 
FocusMotion Brace 
Balance: tandem stance 
scale 
PT measurement 
Balance:Standing on one leg 
Scale 
PT measurement 
10m walk test for speed 
Seconds 
PT measurement 
6 minute walk test 
Meters 
PT measurement 
Timed up and go test 
seconds 
PT measurement 
 
 
 
5 times sit to stand 
Seconds 
PT measurement 
30 sec chair stand test 
count 
PT measurement 
Timed Stair climb  
seconds 
PTmeasurement 
Quadriceps strength 
N 
PT measurement 
Hamstrings strength 
N 
PT measurement 
Pittsburgh Sleep Quality Index 
scale 
FocusMotion App Survey 
Oxford knee score  
scale 
 FocusMotion App Survey 
FJS 
scale 
FocusMotion App Survey 
Visual Analog Scale pain score thigh 
scale 
FocusMotion App Survey 
Visual Analog Scale pain score knee 
scale 
FocusMotion App Survey 

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Visual Analog Scale pain score leg/calf 
scale 
FocusMotion App Survey 
% normal knee 
Scale 
FocusMotion App Survey 
Use of assistive device 
incidence 
FocusMotion App Survey 
Narcotic requirement, daily 
Daily MME/hr 
FocusMotion App survey 
Sleep duration 
min 
Fitbit 
Sleep quality (REM sleep/non-REM sleep) 
percentage 
Fitbit 
Sleep disturbances 
count 
Fitbit 
Sleep efficiency(time asleep/time in bed) 
percentage 
Fitbit 
Charleston Comorbidity Index 
Score 
EPIC CPAP documentation 
PROMIS 
Score 
WUPRO 
 
Table 4: Intra-operative data during procedure 
Test 
Unit 
Collected by 
Tourniquet time 
 
Surgeon 
Tourniquet pressure 
 
Surgeon 
Length of surgery 
 
Surgeon 
 
 
Table 5: Post-operative data during hospital stay 
Test 
Unit 
Collected by 
Length of stay 
Hours 
Chart review 
Day of discharge 
number 
Chart review 
Total calculated blood loss 
mL 
Chart review 
Occurrence of transfusion 
incidence 
Chart review 
 
 
 
 
 
 
VAS pain score (q8hr) 
scale 
Nursing 
Narcotic requirements, PACU to discharge MME/hr 
Chart review 
Perioperative complications 
incidence 
Chart review 
 
 
 
 
Table 6: Daily data points, from postop day 0 to 12 weeks postop 
Data 
Unit 
Collected by 
VAS pain score 
Scale 
FocusMotion App Survey 
Total prescribed morphine equivalents 
Pills/day 
EPIC 
Narcotic requirement, daily 
MME/hr 
FocusMotion App Survey 
Sleep duration 
Min 
Fitbit 
Sleep disturbances 
Count 
FItbit 

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Sleep efficiency (time asleep/time in bed) 
percenta
ge 
Fitbit 
Sleep quality (REM sleep/non-REM sleep) 
Percenta
ge 
Fitbit 
Step count 
Count 
Fitbit 
Use of assistive device 
Incidence FocusMotion App Survey 
Active Knee ROM 
degrees 
FocusMotion Brace 
Passive Knee ROM 
degrees 
FocusMotion Brace 
Compliance with home PT protocol 
incidence 
FocusMotion App 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table 7: Post-operative data at 3 months following procedure 
Knee circumference 
cm 
PT measurement 
Passive Knee ROM 
degrees 
PT measurement 
Active Knee ROM 
degrees 
FocusMotion Brace 
Balance: tandem stance 
scale 
PT measurement 
Balance: Standing on One Leg 
scale 
PT measurement 
10m walk test for speed 
seconds 
PT measurement 
6 minute walk test 
meters 
PT measurement 
Timed up and go test 
seconds 
PT measurement 
5 times sit to stand 
seconds 
PT measurement 
30 sec chair stand 
count 
PT measurement 
Timed stair climb 
seconds 
PT measurement 
Quadriceps strength 
N 
PT measurement 
Hamstrings strength 
N 
PT measurement 
PSQI 
scale 
FocusMotion App Survey 
Oxford Knee Score 
scale 
FocusMotion App Survey 
% normal knee 
scale 
FocusMotion App Survey 
 FJS 
scale 
FocusMotion App Survey 
VAS pain score 
scale 
FocusMotion App Survey 
Use of assistive device 
incidence 
FocusMotion App Survey 

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Narcotic requirement 
daily MME/hr 
FocusMotion App Survey 
Sleep duration 
min 
Fitbit 
Sleep disturbances 
count 
Fitbit 
Sleep efficiency (time asleep/time in 
bed) 
percentage 
Fitbit 
Sleep quality (REM sleep/non-REM 
sleep) 
percentage 
Fitbit 
PROMIS 
score 
WUPRO 
Wound complications 
incidence 
EPIC documentation 
DVT/PE 
incidence 
incidence 
Infection 
incidence 
EPIC documentation 
Return to OR 
incidence 
EPIC documentation 
Patient questionnaire about app and 
Fitbit/brace usage 
questionnaire Paper questionnaire or 
through app 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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