Pain After Total Knee Arthroplasty: A Trial Examining Combined Adductor-canal Nerve Block and Periarticular Infiltration Versus Adductor Canal Nerve Block Versus Periarticular Infiltration

Effective pain management following total knee arthroplasty is important to facilitate early mobilization and rehabilitation. To manage post-operative pain, multimodal analgesia, including acetaminophen, NSAID's, gabapentin, opioids and local anesthetics are used. However, local anesthetics injected into the femoral nerve area may cause a block in motor function of the quadriceps muscle. Both adductor-canal peripheral nerve block performed pre-operatively, and periarticular infiltration performed intra-operatively are effective in reducing pain following TKA without causing quadriceps motor block which can impede mobilization. No published trials have been found that compare single shot adductor-canal block plus periarticular infiltration to periarticular infiltration only or adductor-canal nerve block only. The purpose of this trial is to examine the effect of 3 different approaches to nerve blockade: 1) adductor-canal block plus periarticular infiltration; 2) adductor-canal block only; 3) periarticular infiltration only, on pain, analgesic consumption, mobility, pain related interference with activities and length of hospital stay in participants undergoing unilateral TKA. Patients will be eligible for participation if they are 18 years old or older, and can speak, and read English. Ninety-six trial participants will be randomized to receive 1 of the 3 approaches to nerve blockade as part of their pain management plan. Outcomes will be measured on post-operative days 1 and 2 and length of stay will be calculated in hours after the participant is discharged to home. It is hypothesized that participants that receive both adductor-canal nerve block plus periarticular infiltration will report less pain, improved mobility and less pain related interference with activities.