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Tourniquet on Total Knee Arthroplasty

Impact on Tourniquet Use on Functional Outcomes and Complications After TKA

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04923724
Enrollment
165
Registered
2021-06-11
Start date
2020-11-01
Completion date
2024-11-27
Last updated
2025-05-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Arthritis Knee

Brief summary

The purpose of this study is determine the effect on novel pressure-regulating tourniquet use on pain, functional recovery, sleep and total blood loss following total knee arthroplasty.

Detailed description

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. 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. 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 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 . 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. Sleep quality is affected in the immediate post-operative period after TKA as well, but improves by 3-6 months post-operatively . 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.

Interventions

DEVICEtourniquet

tourniquet is a device used during total knee surgery.

tourniquet is a device used during total knee surgery, this group does not get one

Sponsors

Zimmer Biomet
CollaboratorINDUSTRY
Washington University School of Medicine
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Masking description

Participants do not know which group they are in.

Intervention model description

Patients are put into 2 study groups. One group gets a tourniquet during surgery and one group does not.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Age 18 and up * Primary unilateral TKA * BMI\<45 * Primary diagnosis of osteoarthritis * Patient has a iOS or Android smartphone capable of running FitBit and FocusMotion applications

Exclusion criteria

* Revision TKA * Bilateral TKA * Pregnancy * Prisoners * Pre-existing functionally-limiting neurologic disorder * Narcotic dependence, defined as oxycodone/hydrocodone use \>5days/week * History of unprovoked VTE/PE * Inability to complete baseline functional testing

Design outcomes

Primary

MeasureTime frameDescription
Pain After TKA Measured by VAS Pain Survey on Focusmotion App1 yearEffect of tourniquet use on pain after TKA, 0-10 scale with 10 being higher pain, VAS pain survey

Secondary

MeasureTime frameDescription
Functional Recovery Measured by Oxford Knee Score Scale1 yearEffect of tourniquet use on functional recovery after TKA. Score each question (item) from 0 to 4 with 0 being the worst outcome and 4 being the best outcome. The scores are then summed to produce an overall score running from 0 (worst possible) to 48 (best outcome).
Functional Recovery Measured by Forgotten Joint Score1 yearEffect of tourniquet use on functional recovery after TKA. Scale measures how much patient is aware of their joint after surgery. a total of 12 questions are answered asking about awareness of the knee joint. Every question is scored 1 (never) to 5 (mostly) according to the selected response categories. Thus, the raw score ranges from 12 to 60. The raw score is linearly transformed to a 0-100 scale and then reversed to obtain the final score. Final score = 100 - ((sum(item01 to item12) - 12)/48\*100) 0:Represents the worst possible score, indicating the highest level of joint awareness and the least ability to forget. 100:Represents the best possible score, indicating the lowest level of joint awareness and the greatest ability to forget
Functional Recovery Measured by Normal Knee Survey1 yearEffect of tourniquet use on functional recovery after TKA measured by a score of 0-100, 100 being knee feels normal, 0 means knee does not feel normal

Other

MeasureTime frameDescription
Hours of Sleep Per Night Postoperatively3 monthsInvestigate sleep quality in post-operative period after TKA using fitbit tracker average hours of sleep at night
Total Blood Loss1 dayeffect of tourniquet use on total calculated blood loss after TKA. this is calculated by change in hemoglobin in g/dL from preop to periop.

Countries

United States

Participant flow

Participants by arm

ArmCount
Tourniquet During Surgery
Patients in this group get a tourniquet during surgery. tourniquet: tourniquet is a device used during total knee surgery.
57
No Tourniquet During Surgery
Patients in this group do not get a tourniquet during surgery. No tourniquet: tourniquet is a device used during total knee surgery, this group does not get one
58
Total115

Baseline characteristics

CharacteristicNo Tourniquet During SurgeryTotalTourniquet During Surgery
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
19 Participants33 Participants14 Participants
Age, Categorical
Between 18 and 65 years
39 Participants82 Participants43 Participants
Age, Continuous64.6 years64 years63.4 years
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
United States
58 participants115 participants57 participants
Sex: Female, Male
Female
34 Participants56 Participants22 Participants
Sex: Female, Male
Male
24 Participants59 Participants35 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
1 / 570 / 58
other
Total, other adverse events
0 / 570 / 58
serious
Total, serious adverse events
1 / 570 / 58

Outcome results

Primary

Pain After TKA Measured by VAS Pain Survey on Focusmotion App

Effect of tourniquet use on pain after TKA, 0-10 scale with 10 being higher pain, VAS pain survey

Time frame: 1 year

ArmMeasureValue (MEAN)Dispersion
Tourniquet During SurgeryPain After TKA Measured by VAS Pain Survey on Focusmotion App2.8 score on a scaleStandard Deviation 1.5
No Tourniquet During SurgeryPain After TKA Measured by VAS Pain Survey on Focusmotion App2.6 score on a scaleStandard Deviation 1.8
Secondary

Functional Recovery Measured by Forgotten Joint Score

Effect of tourniquet use on functional recovery after TKA. Scale measures how much patient is aware of their joint after surgery. a total of 12 questions are answered asking about awareness of the knee joint. Every question is scored 1 (never) to 5 (mostly) according to the selected response categories. Thus, the raw score ranges from 12 to 60. The raw score is linearly transformed to a 0-100 scale and then reversed to obtain the final score. Final score = 100 - ((sum(item01 to item12) - 12)/48\*100) 0:Represents the worst possible score, indicating the highest level of joint awareness and the least ability to forget. 100:Represents the best possible score, indicating the lowest level of joint awareness and the greatest ability to forget

Time frame: 1 year

Population: not all patients completed this survey, that is why the numbers are inconsistent with other surveys.

ArmMeasureValue (MEAN)Dispersion
Tourniquet During SurgeryFunctional Recovery Measured by Forgotten Joint Score68.4 score on a scaleStandard Deviation 28.2
No Tourniquet During SurgeryFunctional Recovery Measured by Forgotten Joint Score70.9 score on a scaleStandard Deviation 77.4
Secondary

Functional Recovery Measured by Normal Knee Survey

Effect of tourniquet use on functional recovery after TKA measured by a score of 0-100, 100 being knee feels normal, 0 means knee does not feel normal

Time frame: 1 year

Population: not all patients completed this survey, that is why participant numbers are inconsistent with other surveys

ArmMeasureValue (MEAN)Dispersion
Tourniquet During SurgeryFunctional Recovery Measured by Normal Knee Survey79.3 score on a scaleStandard Deviation 90
No Tourniquet During SurgeryFunctional Recovery Measured by Normal Knee Survey81.5 score on a scaleStandard Deviation 20.1
Secondary

Functional Recovery Measured by Oxford Knee Score Scale

Effect of tourniquet use on functional recovery after TKA. Score each question (item) from 0 to 4 with 0 being the worst outcome and 4 being the best outcome. The scores are then summed to produce an overall score running from 0 (worst possible) to 48 (best outcome).

Time frame: 1 year

ArmMeasureValue (MEAN)Dispersion
Tourniquet During SurgeryFunctional Recovery Measured by Oxford Knee Score Scale43.0 score on a scaleStandard Deviation 6.28
No Tourniquet During SurgeryFunctional Recovery Measured by Oxford Knee Score Scale41.37 score on a scaleStandard Deviation 8.84
Other Pre-specified

Hours of Sleep Per Night Postoperatively

Investigate sleep quality in post-operative period after TKA using fitbit tracker average hours of sleep at night

Time frame: 3 months

ArmMeasureValue (MEAN)Dispersion
Tourniquet During SurgeryHours of Sleep Per Night Postoperatively5.41 hours of sleepStandard Deviation 2.23
No Tourniquet During SurgeryHours of Sleep Per Night Postoperatively6.47 hours of sleepStandard Deviation 1.63
Other Pre-specified

Total Blood Loss

effect of tourniquet use on total calculated blood loss after TKA. this is calculated by change in hemoglobin in g/dL from preop to periop.

Time frame: 1 day

ArmMeasureValue (MEAN)Dispersion
Tourniquet During SurgeryTotal Blood Loss13.9 g/dL hemoglobinStandard Deviation 1.4
No Tourniquet During SurgeryTotal Blood Loss11.5 g/dL hemoglobinStandard Deviation 1.3

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026