Too few recruitable patients

This project investigates the relation between acute pain and local inflammation. Pain reported by the patients for knee arthroscopy are compared with local changes in inflammatory mediators by using microdialysis technique. Patients with moderate-to-severe pain are included in a randomized placebo-controlled trial of anakinra given intra-articularly.

The effects of the recombinant IL-1 receptor antagonist anakinra both on acute pain and post operative inflammation will be evaluated. On inclusion, pain intensity will be measured on a five-point verbal rating scale (0= no pain, 1=mild pain, 2=moderate pain, 3=severe pain, and 4=intolerable pain), and on a visual analogue scale (0-100mm). VAS scale will be repeated at 20, 40, 60, 80, 100, 120, 140, 160, 180 and 200 minutes after inclusion / intervention. The patients will also rate pain intensity during a 5 meters walk at 200 minutes (evoked pain). The patient will rate pain at rest and evoked pain 24, 48 and 72 h after intervention.

Inclusion Criteria:

1. Otherwise healthy patients (ASA 1 and 2) undergoing knee arthroscopy in general anaesthesia.
2. Being informed about and willing to participate in the study -

Exclusion Criteria:

1. Pregnancy or lactation. Fertile women will be asked if they may be pregnant, and offered a pregnancy test if there is doubt.
2. Established osteoarthritis or synovitis
3. Known intolerance to anakinra
4. Kidney failure (Creatinine clearance <30ml/min)
5. History of frequent infectious diseases or immunodeficiency
6. Heart failure
7. History of drug -or alcohol abuse
8. Participation in other synchronous clinical trials
9. Perioperative steroid treatment, perioperative paracetamol (12 hrs), NSAIDs (24 hrs) or COX2-inhibitors (48 hrs).
10. Use of tourniquet for bloodless field
11. Strong preoperative pain (VRS ≥3)
12. Intolerable postoperative pain (VRS=4)