The Effects of a Tourniquet in Total Knee Arthroplasty.

Study Overview
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Brief Summary
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About 5000 total knee arthroplasties (TKA) are performed annually in Norway. Pain and reduced physical function is present in patients operated with TKA up to a year after surgery and about one of five patients are not satisfied with the outcome from TKA surgery. The use of tourniquet during surgery may also have impact on pain and physical function. Whether TKA surgery should be performed with or without the use of tourniquet, is a much-debated issue in orthopedic surgery today, and there is still no consensus in this field. This study will investigate early muscle strength and power recovery, neuromuscular recordings, neuronal changes and patient reported outcome measures after surgery with tourniquet versus not tourniquet.The findings in this study are expected to have implications for rehabilitation and the outcome of the TKA surgery.

Official Title
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The Effects of a Tourniquet on Implant Migration and Muscle Strength and Function in Patients Operated With Total Knee Arthroplasty

Conditions
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Osteoarthritis, Knee

Intervention / Treatment
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* Device: Tourniquet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Knee osteoarthrosis qualifying for total knee arthroplasty Exclusion Criteria: Coagulation disease Rheumatoid arthritis Peripheral vascular disease Malign disease Pregnancy On-going infection Not able to understand written and oral information in Norwegian

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: No tourniquet<br>No use of tourniquet during surgery | |
| Experimental: Tourniquet<br>Use of tourniquet during surgery. The cuff will be inflated to 300mmHg | Device: Tourniquet<br>* In the patients randomized to the use of tourniquet, the tourniquet time starts before skin incision and terminates when the wound closure starts. The cuff pressure is set at 300mmHg.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mmax | EMG recordings are made using 10mm electrodes (Ag-AgCl) attached in a bipolar configuration over the vastus lateralis and rectus femoris | Change from 1) preoperative (baseline) to day 2 postoperative, 2) change from preoperative to 8 weeks postoperative, 3) change from preoperative to 1 year postoperative | 
| Nerve growth factor (NGF) | Analysis from muscle biopsies harvested from the m. vastus lateralis | Change from during surgery to 8 weeks postoperative | 
| Forgotten Joint Score | The stair climbing test measures the time (in seconds) to ascend, turn around and descend a regular stairway of 11 steps. The patients are asked to perform the test as quickly as possible. | Change from 1) preoperative (baseline) to 2) change from preoperative to 8 weeks postoperative, 3) change from preoperative to 1 year postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal leg strength | 1RM leg strength is measured using a leg press ergometer with the participant in a supine position (Steens Physical; Ring Mekanikk, Moelv, Norway) | Change from 1) preoperative (baseline) to day 2 postoperative, 2) change from preoperative to 8 weeks postoperative, 3) change from preoperative to 1 year postoperative | 
| Maximal knee extension strength | 1RM knee extension is measured using a knee extension equipment (Body-Solid, Forest Park, IL, USA) with the participant in a seated position. | Change from 1) preoperative (baseline) to day 2 postoperative, 2) change from preoperative to 8 weeks postoperative, 3) change from preoperative to 1 year postoperative | 
| Rate of force development, voluntary activation and muscle contractility |  | Change from 1) preoperative (baseline) to day 2 postoperative, 2) change from preoperative to 8 weeks postoperative, 3) change from preoperative to 1 year postoperative | 
| Daily physical activity | Body worn activity monitor | Change from day 3 - 10 postoperative to 1 year postoperative (1 week measurement) | 
| EuroQual 5D-L | Patient reported outcome measure | Preoperative, 8 weeks, 1 year postoperative | 
| Numeric Rating Scale (NRS) | Evaluating pain. The scale range from 0 (no pain) to 10 (worst pain imaginable) (7). The patients are asked to write down NRS values both at rest and during activity each day for the first 4 weeks postoperatively in a home log. | Preoperative, from day 1 postoperative to 4 weeks postoperative, 8 weeks and 1 years postoperative | 
| Hemoglobin values | g/dL | Preoperatively, day 1 postoperative | 
| Volume of bleeding | Total volume of bleeding during surgery and in the drain | During surgery and day 1 postoperative | 
| Length of hospital stay | Number of days | From day of surgery until 10 days postoperative | 
| Knee circumference | The circumference of the knee is measured 1 cm proximal to the patella base | Preoperative and day 1 postoperative | 
| Knee joint range of motion | Maximal flexion and extension | Preoperative, 1 day, 8 weeks,1 year postoperative | 
| Forgotten Joint Score | Patient reported outcome measure | Preoperative, 8 weeks, 1 year postoperative | 
| Gene expression analyses. RT-PCR for expression levels for VEGF, NGF, SP, CGRP, IL-6, IL-1, TNF-alpha, Bad, Bax, Bid, Bim, Fas, Fas-ligand, Bcl-2, Mcl, and FLIP. Results will be normalized to GAPDH expression levels. | Analysis from muscle biopsies harvested from the vastus lateralis (muscle) | Peroperative and 8 weeks postoperative | 
| Neuronal markers; PGP, GAP-43 | Analysis from muscle biopsies harvested from the vastus lateralis (muscle) | During surgery and 8 weeks postoperative | 
| Neuromediators; SP, CGRP, glutamate | Analysis from muscle biopsies harvested from the vastus lateralis (muscle) | During surgery and 8 weeks postoperative | 
| Pain receptors; glutamate receptors | Analysis from muscle biopsies harvested from the vastus lateralis (muscle) | During surgery and 8 weeks postoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Arthroplasty, Replacement, Knee, Tourniquets, Pain, postoperative, Muscle strength