Dexamethasone and Functional Outcome After TKA

Study Overview
=================
Brief Summary
-----------------
Patients previously included in the DEX-2-TKA-trial (ethics committee ID SJ-695; ClinicalTrials.gov: NCT03506789) at Næstved Hospital will be invited for a follow up study consisting of questionnaires and a visit with a physical therapist. The study includes the following validated questionnaires: EQ-5D-5L, Oxford Knee Score and PainDetect, and information on height, weight, daily pain-medication and co-morbidities. With the physical therapist, the patient will perform the following functional tests: knee range of motion, timed-up-to-go, 30 second chair stand test, 40m fast paced walk test, stair climb test and a measure of the thigh force.

Official Title
-----------------
Dexamethasone and Functional Outcome After Total Knee Arthroplasty: A 2 Year Follow up of the DEX-2-TKA-trial

Conditions
-----------------
Chronic Knee Pain, Dexamethasone, Total Knee Arthroplasty

Intervention / Treatment
-----------------
* Drug: Dexamethasone
* Drug: Isotonic saline


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: participation in the DEX-2-TKA-trial at Næstved Hospital in accordance with protocol Signed, informed consent for participation Exclusion Criteria: Lack of signed, informed consent

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Treatment A<br>24mg dexamethasone i.v. perioperatively and 24mg dexamethasone i.v. on the first postoperative day | Drug: Dexamethasone<br>* 24mg dexamethasone<br>|
| Active Comparator: Treatment B<br>24mg dexamethasone i.v. perioperatively and placebo (isotonic saline) i.v. on the first postoperative day | Drug: Dexamethasone<br>* 24mg dexamethasone<br>Drug: Isotonic saline<br>* Isotonic saline<br>|
| Placebo Comparator: Treatment C<br>Placebo (isotonic saline) i.v. perioperatively and placebo (isotonic saline) i.v. on the first postoperative day | Drug: Isotonic saline<br>* Isotonic saline<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average pain during functional performance exercises | Average of maximal pain experienced during the functional performance exercises measured as a VAS 0-100mm with comparisons between treatment allocation group. The average will be calculated based on measurements after each functional performance exercise (TUG, 30CST, 40FPW and SCT). | 2-3 years after total knee arthroplasty | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| EQ-5D-5L | Difference in performance between treatment allocation groups on the EQ-5D-5L questionnaire at follow-up. EQ-5D-5L is comprised of five health dimensions (mobility, self-care, usual activities, pain/discomfort) which the patient must rate on a 1-5 dimension going from no problems to perform the activity to being unable to perform the activity. In addition, the patient will rate his/her health on a 0-100 scale, where 0 being worst imaginable health and 100 being best imaginable health. | 2-3 years after total knee arthroplasty | 
| Oxford Knee Score | Difference in performance between allocation groups on the Oxford Knee Score questionnaire at follow-up. Oxford Knee Score is a questionnaire comprised of 12 questions regarding pnee pain and function. Each question can be answered on a 1 (best) to 5 (worst) score and thus a overall scores can be calculated by summing op all the scores. Best outcome would hence be a score of 12, while worst possible outcome is a score of 60. | 2-3 years after total knee arthroplasty | 
| PainDetect | Difference in performance between allocation groups on the PainDetect questionnaire at follow-up. The PainDetect questionnaire is comprised of 11 questions regarding strengt and character of any experienced pain. The patients answers can then be calculated into a total score of 0-38 and further grouped into likelihood of a neuropathic component of the patients chronic pain. If 0-12 there is <15% likelihood that the patient experiences neuropathic pain, while >18 estimates a likelihhed >90% for a neuropathic component. 13-18 points is a greyzone in between where a neuropathic component of the experienced pain cannot either be ruled in or out. | 2-3 years after total knee arthroplasty | 
| Use of opioids | Difference in daily use of opioids between allocation groups at follow-up. Daily use will be calculated into equivalents of mg morphine per day. | 2-3 years after total knee arthroplasty | 
| Range of Motion | Difference in performance between allocation groups on the Range of Motion exercise at follow-up. Range of motion is measured in degrees from fully extended to full flexion of the knee | 2-3 years after total knee arthroplasty | 
| Timed-Up-To-Go (TUG) | Difference in performance between allocation groups on the timed-up-to-go-test exercise at follow-up assessed as time in seconds it takes to Stand up from the chair Walk to a line on the floor 3 meters away Turn Walk back to the chair Sit down again. The time will be measured from Go to the participant is sitting again. | 2-3 years after total knee arthroplasty | 
| 30 second chair stand test (30CST) | Difference in performance between allocation groups on the 30 second chair-stand-test exercise at follow-up assessed as number of repetitions performed during 30 seconds. one repetition is counted as sitting on a chair with the arms crossed across the chest stand fully up sit down again | 2-3 years after total knee arthroplasty | 
| 40 meter fast paced walk test (40FPW) | Difference in performance between allocation groups on the 40 meter fast paced walk test exercise at follow-up assessed as walk speed in meters pr. second. The exercised is performed by the patient walkning as highest possible speed between to lines on the floor 10 meters apart from each other. A timer is started eache time the patient crossess the line and paused, when the patient is at the other end. After 4 walks between the lines the 40 meters is divided by the total time in seconds and expressed as meters pr. second | 2-3 years after total knee arthroplasty | 
| Stair Climb Test (SCT) | Difference in performance between allocation groups on the stair climb test exercise at follow-up assessed as time in seconds it takes to walk 9 steps up and 9 steps down a flight of stairs. | 2-3 years after total knee arthroplasty | 
| Thigh Force | Difference in thigh force between allocation groups at follow-up assessed during flexion and extension. Force will be measured with an EASYFORCE-apparatus and expressed as newton. | 2-3 years after total knee arthroplasty |