Despite improvements in analgesic treatment following total knee arthroplasty (TKA) for osteoarthrosis, a substantial part of patients still have severe acute pain after surgery. It has been suggested that preoperative degree of intraarticular inflammation is associated to postoperative degree of pain and level of function. Furthermore it is known, that patients with preoperative inflammation have hyperalgesia and severe movement related pain.

The aim of this study is to investigate the effect of a preoperative intraarticular injection of Methylprednisoloneacetate in reducing acute postoperative pain after total knee arthroplasty in patients with signs of severe pre-operative inflammation and pain.

Inclusion Criteria:

• Age 50 -80
• Osteoarthrosis
• Scheduled for primary unilateral TKA
• Preoperative pain report with NRS > 5 upon walking
• Signs of sensitisation in knee

Exclusion Criteria:

• Allergies to methylprednisoloneacetate, lidocaine or standard analgesic treatment
• Deficient written or spoken danish
• Impairment from psychological or neurological disease
• Local og systemic infection
• Immunodeficiency
• Treatment with corticosteroid within 30 days of inclusion
• Insulin treated diabetes mellitus
• Anticoagulant therapy
• ASA (American Society of Anaesthesia) class > 3
• General anaesthesia
• Alchohol use > 21 units / week
• Pregnancy