Osteo Arthritis KneeNCT04502459
A Study on the Use of Tourniquet Use In Primary Total Knee Arthroplasty
A study testing Tourniquet in people with Osteo Arthritis Knee and Rheumatoid Arthritis of Knee, run by The University of Hong Kong.
Trial summary
A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Osteo Arthritis Knee, Rheumatoid Arthritis of Knee
- What is being tested?
- Tourniquet
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 90 participants
- Where
- No sites listed yet
- Study dates
- 5 May 2015to 15 Dec 2017
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients suffer from primary osteoarthritis indicated for total knee arthroplasty
- Subject is physically and mentally willing and able to comply with the postoperative scheduled clinical and radiographic evaluations
- Subject must have signed an informed consent document specific to the study, and approved by the Ethics Committee, indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study
Who cannot join
- Subject requires a revision knee arthroplasty surgery
- Subject is currently on anti-coagulant therapy or has coagulopathy
- Subject has peripheral vascular disease of the lower limb evidenced by the presence of blood vessel calcification on the radiographs or the absence of dorsalis pedis/popliteal pulses
- Subject suffers from conditions other than primary knee osteoarthritis, e.g. inflammatory arthritis
- Subject having associated medical diseases affecting rehabilitation
- Subject has active systemic infection or infection near the knee joint
- Subject having current medical condition that render them unfit for surgery
- Any criterion which in the opinion of the investigator, suggests that the subject would not be compliant with the study protocol
About this study
Official title: A Prospective Randomized Trial on the Use of Tourniquet in Primary Total Knee Arthroplasty
A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and thromboembolic events. The automatic lower limb pneumatic tourniquet system (Zimmer) was applied to reduce blood loss during surgery. A prospective randomized controlled trial (RCT) was performed to investigate the best tourniquet strategy in TKA. The participants were randomly allocated to groups with different tourniquet strategies: Group 1) tourniquet inflation from skin to cement hardening (skin to cement); Group 2) tourniquet inflation only from cementation (cement only) and Group 3) tourniquet inflation from skin incision to skin closure (skin to skin). In addition to the blood loss and early postoperative outcomes, pain, soft tissue injury, and rehabilitation were also strictly monitored with a longer follow-up duration up to 6 months.
Read the detailed description
A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and thromboembolic events.
The automatic lower limb pneumatic tourniquet system (Zimmer) was applied to reduce blood loss during surgery. The skin under the tourniquet was covered by cast padding. The operated leg was elevated and exsanguinated before inflating the automatic pneumatic tourniquet. There are three main strategies for the use of a tourniquet in TKR: A) inflate before incision and deflate following cement hardening ('skin to cement'); B) inflate prior to cement application and deflated following hardening ('cement only'); C) inflate before incision and deflate following completion of skin closure ('skin to skin'). The optimal timing of tourniquet application during primary TKA is still a matter of debate. Most previous reports have failed to show significant differences among different tourniquet strategies.
Kvederas et al. compared these three strategies in a randomized double-blind clinical trial, and demonstrated that the estimated blood loss was highest when the tourniquet was inflated just before cement application and deflated after its hardening ('cement only'), while inflation of tourniquet before skin incision and its deflation after hardening of cement ('skin to cement') tends to give better early postoperative mobilization. However, this was an interim report with limited number of patients, and only limited outcome parameters were reported, which were insufficient to draw firm conclusions regarding the differences in outcome.
Therefore we performed this prospective randomized controlled trial (RCT) with a decent sample size to investigate the best tourniquet strategy in TKA. In addition to the blood loss and early postoperative outcomes, we also strictly monitored pain, soft tissue injury, and rehabilitation with a longer follow-up duration up to 6 months.
All of the operations were performed through the medial parapatellar approach by the same experienced joint replacement surgeon. All patients underwent primary TKA with minimally invasive techniques and cemented prostheses (EvolutionTM medial pivot, MicroPort, USA). An intramedullary guide was used for both tibial and femoral cuts.
The automatic lower limb pneumatic tourniquet system was applied to reduce blood loss during surgery. The skin under the tourniquet was covered by cast padding. The operated leg was elevated and exsanguinated before inflating the automatic pneumatic tourniquet. One of the three tourniquet treatment strategies was used, as determined by the group allocation of the patient. In all the three groups, the tourniquet was inflated to a pressure of 280 mm Hg. The wound was closed after wound irrigation and hemostasis and then was wrapped with elastic bandages. One drainage was applied postoperatively in all patients and was kept until 24h to monitor blood loss.
- Conditions
- Osteo Arthritis Knee, Rheumatoid Arthritis of Knee
- Being tested
- Tourniquet
- Keywords
- Tourniquet, Total Knee Arthroplasty
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
TourniquetProcedure or surgery
A tourniquet is often used in total knee arthroplasty to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation
| Study group | Role | What they receive |
|---|---|---|
| Cement only | Active comparator | The tourniquet was inflated just before cement application and deflated after its hardening Receives: Procedure: Tourniquet |
| Skin to Cement | Active comparator | Inflation of tourniquet before skin incision and its deflation after hardening of cement Receives: Procedure: Tourniquet |
| Skin to Skin | Active comparator | Inflate of tourniquet before incision and deflate following completion of skin closure Receives: Procedure: Tourniquet |
What is being measured
The primary outcome is the main question the study is designed to answer.
Blood Loss
We calculated the intraoperative blood loss by measuring the suction volume and weighing the sponges. Hemoglobin (Hb) and hematocrit (Hct) levels were examined preoperatively, and on Day 1 to Day 4 after surgery. Change of Hb and Hct was calculated as the value of postoperative D1 to D4 minus preoperative value. The number of patients undergoing blood transfusion were recorded. The criterion for a blood transfusion was set as a Hb level of <8 g/dL with symptomatic anemia. The calculated blood loss, which reflects actual blood loss, was determined with use of a previously described method. Briefly, the patients blood volume (PBV) is calculated using a formula, and multiplying the PBV by the change of haematocrit (preoperative value minus value on postoperative Day 2) will give the estimated total blood loss (ETBL).
Measured: 4 days after surgery
Secondary outcomes (9)
Soft-tissue damage
We assessed soft-tissue damage by examining serum C-reactive protein (CRP), creatine kinase (CK), lactate dehydrogenase (LDH), and interleukin-6 (IL-6) levels preoperatively and on postoperative days 1, 2, 3 and 4
Measured: 4 days after surgery
Thigh circumference
Thigh circumference was measured 10 cm proximal to the patella and leg circumference was measured 15 cm distal to the patella, to determine the degree of swelling, and was measured on postoperative days 1, 2, 3 and 4. X-rays were taken after surgery to measure the lower limb alignment, and tibial and femoral components position.
Measured: 4 days after surgery
Postoperative Visual Analog Scale
Postoperative visual analog scale (VAS) scores were obtained for both knee and thigh pain preoperatively and on postoperative.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Peak Quadriceps Strength
The strength of each leg was evaluated by using an isokinetic dynamometer. Peak torque measured in both the concentric and eccentric modes.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Time-up-and-go (TUG) Test
he TUG test was used to evaluate the preoperative degree of mobility. This test involves measuring the time a patient needs to get up from a chair, walk three meters, turn, walk back to the chair and then sit down again.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
6-minute Walking Test
A test that evaluates the functional capacity of the patient while walking on a flat, hard surface in the 6-minute window. It assess all the systems that are involved in the 6-minute window.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Berg Balance Scale
The BBS test is used to objectively determine a patient's ability (or inability) to safely balance during a series of predetermined tasks.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Knee Society Knee Score
A knee score that rates only the knee joint itself, there are three main parameters which are pain, stability and the range of motion. Whereas flexion contracture, extension lag and misalignment would be different ways for point deductions. 100 points would refer to a patient with no knee pain, 125 degree range of motion and negligible anteroposterior and mediolateral instability.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Knee Society Function Score
A functional score that rates the patient's ability to walk and climb stairs, points would be deducted if the patient uses any walking aids for the two. 100 points would refer to a patient that can walk for an unlimited distance and go up and down the stairs without any trouble.
Measured: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Aug 2020
- Study start5 May 2015
- Primary completion15 Dec 2017
- Study completion15 Dec 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Osteo Arthritis KneeStudies of the same condition, open and under way.
- More trials run by The University of Hong KongThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- A randomization list was generated prior to recruitment using a computer software (Random Allocation Software Version 1.0.0, Isfahan, Iran). The participants were randomly allocated to either of the 3 groups with different tourniquet strategies: Group 1) tourniquet inflation from skin to cement hardening (skin to cement); Group 2) tourniquet inflation only from cementation (cement only); Group 3) tourniquet inflation from skin incision to skin closure (skin to skin). The surgeon opened a sealed envelope containing the allocation right before the operation in the theatre. The evaluators who examined and collected the data were blinded to the patients' allocation to the study groups.
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 90 participants (actual)
Sponsor and investigators
- Lead sponsor
- The University of Hong Kong
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Dr. Yan Chun-Hoi, The University of Hong Kong
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04502459
- Sponsor's protocol ID
- UW 15-129
- Status last verified
- Aug 2020
- First submitted
- 14 Jul 2020
- Last updated
- 6 Aug 2020
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Tai TW, Chang CW, Lai KA, Lin CJ, Yang CY. Effects of tourniquet use on blood loss and soft-tissue damage in total knee arthroplasty: a randomized controlled trial. J Bone Joint Surg Am. 2012 Dec 19;94(24):2209-15. doi: 10.2106/JBJS.K.00813.
PubMed 23318610Tarwala R, Dorr LD, Gilbert PK, Wan Z, Long WT. Tourniquet use during cementation only during total knee arthroplasty: a randomized trial. Clin Orthop Relat Res. 2014 Jan;472(1):169-74. doi: 10.1007/s11999-013-3124-2.
PubMed 23836239
Study at a glance
From the registry record, last updated by the sponsor on 6 Aug 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective Randomized Trial on the Use of Tourniquet in Primary Total Knee Arthroplasty
- ClinicalTrials.gov ID
- NCT04502459
- Acronym / sponsor ID
- UW 15-129
- Conditions
- Osteo Arthritis Knee, Rheumatoid Arthritis of Knee
- Keywords
- Tourniquet, Total Knee Arthroplasty
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 90 participants (actual)
- Lead sponsor
- The University of Hong KongUniversity, hospital or other
- Study start
- 5 May 2015 (actual)
- Primary completion
- 15 Dec 2017 (actual)
- Study completion
- 15 Dec 2017 (actual)
- First posted
- 6 Aug 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and thromboembolic events. The automatic lower limb pneumatic tourniquet system (Zimmer) was applied to reduce blood loss during surgery. A prospective randomized controlled trial (RCT) was performed to investigate the best tourniquet strategy in TKA. The participants were randomly allocated to groups with different tourniquet strategies: Group 1) tourniquet inflation from skin to cement hardening (skin to cement); Group 2) tourniquet inflation only from cementation (cement only) and Group 3) tourniquet inflation from skin incision to skin closure (skin to skin). In addition to the blood loss and early postoperative outcomes, pain, soft tissue injury, and rehabilitation were also strictly monitored with a longer follow-up duration up to 6 months.
Detailed description
A tourniquet is often used in total knee arthroplasty (TKA) to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation. On the other hand, the associated risks include skin burns, soft tissue and muscle damage, injury of calcified vessels, increased swelling and stiffness of the joints, nerve injury, paralysis, and thromboembolic events.
The automatic lower limb pneumatic tourniquet system (Zimmer) was applied to reduce blood loss during surgery. The skin under the tourniquet was covered by cast padding. The operated leg was elevated and exsanguinated before inflating the automatic pneumatic tourniquet. There are three main strategies for the use of a tourniquet in TKR: A) inflate before incision and deflate following cement hardening ('skin to cement'); B) inflate prior to cement application and deflated following hardening ('cement only'); C) inflate before incision and deflate following completion of skin closure ('skin to skin'). The optimal timing of tourniquet application during primary TKA is still a matter of debate. Most previous reports have failed to show significant differences among different tourniquet strategies.
Kvederas et al. compared these three strategies in a randomized double-blind clinical trial, and demonstrated that the estimated blood loss was highest when the tourniquet was inflated just before cement application and deflated after its hardening ('cement only'), while inflation of tourniquet before skin incision and its deflation after hardening of cement ('skin to cement') tends to give better early postoperative mobilization. However, this was an interim report with limited number of patients, and only limited outcome parameters were reported, which were insufficient to draw firm conclusions regarding the differences in outcome.
Therefore we performed this prospective randomized controlled trial (RCT) with a decent sample size to investigate the best tourniquet strategy in TKA. In addition to the blood loss and early postoperative outcomes, we also strictly monitored pain, soft tissue injury, and rehabilitation with a longer follow-up duration up to 6 months.
All of the operations were performed through the medial parapatellar approach by the same experienced joint replacement surgeon. All patients underwent primary TKA with minimally invasive techniques and cemented prostheses (EvolutionTM medial pivot, MicroPort, USA). An intramedullary guide was used for both tibial and femoral cuts.
The automatic lower limb pneumatic tourniquet system was applied to reduce blood loss during surgery. The skin under the tourniquet was covered by cast padding. The operated leg was elevated and exsanguinated before inflating the automatic pneumatic tourniquet. One of the three tourniquet treatment strategies was used, as determined by the group allocation of the patient. In all the three groups, the tourniquet was inflated to a pressure of 280 mm Hg. The wound was closed after wound irrigation and hemostasis and then was wrapped with elastic bandages. One drainage was applied postoperatively in all patients and was kept until 24h to monitor blood loss.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 3
- Model description
- A randomization list was generated prior to recruitment using a computer software (Random Allocation Software Version 1.0.0, Isfahan, Iran). The participants were randomly allocated to either of the 3 groups with different tourniquet strategies: Group 1) tourniquet inflation from skin to cement hardening (skin to cement); Group 2) tourniquet inflation only from cementation (cement only); Group 3) tourniquet inflation from skin incision to skin closure (skin to skin). The surgeon opened a sealed envelope containing the allocation right before the operation in the theatre. The evaluators who examined and collected the data were blinded to the patients' allocation to the study groups.
| Arm | Type | Receives |
|---|---|---|
| Cement only | Active comparator | Procedure: TourniquetThe tourniquet was inflated just before cement application and deflated after its hardening |
| Skin to Cement | Active comparator | Procedure: TourniquetInflation of tourniquet before skin incision and its deflation after hardening of cement |
| Skin to Skin | Active comparator | Procedure: TourniquetInflate of tourniquet before incision and deflate following completion of skin closure |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Patients suffer from primary osteoarthritis indicated for total knee arthroplasty
- Subject is physically and mentally willing and able to comply with the postoperative scheduled clinical and radiographic evaluations
- Subject must have signed an informed consent document specific to the study, and approved by the Ethics Committee, indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study
Key exclusion criteria (8 listed)
- Subject requires a revision knee arthroplasty surgery
- Subject is currently on anti-coagulant therapy or has coagulopathy
- Subject has peripheral vascular disease of the lower limb evidenced by the presence of blood vessel calcification on the radiographs or the absence of dorsalis pedis/popliteal pulses
- Subject suffers from conditions other than primary knee osteoarthritis, e.g. inflammatory arthritis
- Subject having associated medical diseases affecting rehabilitation
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| TourniquetA tourniquet is often used in total knee arthroplasty to achieve better visualization, reduce intra-operative bleeding and facilitate cement interdigitation | Procedure or surgery | Cement only, Skin to Cement, Skin to Skin |
Primary outcome
Blood Loss
Time frame: 4 days after surgery
We calculated the intraoperative blood loss by measuring the suction volume and weighing the sponges. Hemoglobin (Hb) and hematocrit (Hct) levels were examined preoperatively, and on Day 1 to Day 4 after surgery. Change of Hb and Hct was calculated as the value of postoperative D1 to D4 minus preoperative value. The number of patients undergoing blood transfusion were recorded. The criterion for a blood transfusion was set as a Hb level of <8 g/dL with symptomatic anemia. The calculated blood loss, which reflects actual blood loss, was determined with use of a previously described method. Briefly, the patients blood volume (PBV) is calculated using a formula, and multiplying the PBV by the change of haematocrit (preoperative value minus value on postoperative Day 2) will give the estimated total blood loss (ETBL).
9 secondary outcomes
Soft-tissue damage
Time frame: 4 days after surgery
Thigh circumference
Time frame: 4 days after surgery
Postoperative Visual Analog Scale
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Peak Quadriceps Strength
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Time-up-and-go (TUG) Test
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
6-minute Walking Test
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Berg Balance Scale
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Knee Society Knee Score
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Knee Society Function Score
Time frame: Day 1, Day 2, Day 3, Day 4, Day 7, Week 6, Month 3, and Month 6
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Aug 2020.
- Background: PubMed 23318610Tai TW, Chang CW, Lai KA, Lin CJ, Yang CY. Effects of tourniquet use on blood loss and soft-tissue damage in total knee arthroplasty: a randomized controlled trial. J Bone Joint Surg Am. 2012 Dec 19;94(24):2209-15. doi: 10.2106/JBJS.K.00813.
- Background: PubMed 23836239Tarwala R, Dorr LD, Gilbert PK, Wan Z, Long WT. Tourniquet use during cementation only during total knee arthroplasty: a randomized trial. Clin Orthop Relat Res. 2014 Jan;472(1):169-74. doi: 10.1007/s11999-013-3124-2.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
A study testing Tourniquet in people with Osteo Arthritis Knee and Rheumatoid Arthritis of Knee, run by The University of Hong Kong.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Aug 2020. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Blood Loss (time frame: 4 days after surgery). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04502459, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Aug 2020.