Effect of Adductor-Canal-Blockade on High Pain Responders After Total Knee Arthroplasty

Effect of Adductor-Canal-Blockade on High Pain Responders the 1. or 2. Postoperative Day After Total Knee Arthroplasty

The purpose of this study is to determine whether Adductor-Canal-Blockade (ACB) is superior to placebo when it comes to analgetic efficacy in high pain responders after Total Knee Arthroplasty (TKA). High pain responders are defined as patients reporting VAS > 60 during knee flexion the 1. or 2. day after surgery.

The patients will be included the 1. or 2. day after surgery. All TKA patients will be screened. Those reporting VAS > 60 during active 45 degrees knee flexion will be asked to participate.

Included patients will receive 2xACB (singleshot) first placebo (30ml saline) and then ropivacaine (30ml ropivacaine 7,5mg/ml) or the other way around (randomized). There will be 45 minutes between the two blockades. The blockades will be ultrasound guided.

Inclusion Criteria:

• TKA within 48 hours and VAS>60 during active 45 degrees knee flexion despite conventional pain medication.
• Informed consent
• ASA 1-3
• BMI 18-40

Exclusion Criteria:

• Unable to communicate in Danish
• Allergic reactions toward drugs used in the
• Abuse of alcohol/drugs
• Unable to cooperate