Liposomal Bupivacaine Versus Standard Bupivacaine in the Adductor Canal for Total Knee Arthroplasty

Total knee arthroplasty (TKA) can be associated with a large amount of postoperative pain.
This pain can oftentimes be severe enough to limit participation in physical therapy and
ultimately delay discharge resulting in increased cost. Several strategies have been
developed in an effort to decrease postoperative pain following TKA while maintaining lower
extremity strength and maximizing participation in physical therapy. Recently, adductor canal
blockade has gained popularity as it is reported to provide analgesia to the anterior knee
without resulting in significant quadriceps muscle weakness. One downside of single shot
peripheral blockade is the duration of analgesia can oftentimes be short lived. The advent of
depot local anesthetics has made this an attractive option, especially in busy practices
where placing peri-neural catheters may not be practical or cost effective. This study aims
to carefully evaluate this relationship using a physical therapy evaluation method that
relies on both motor strength and pain control. In addition, we hope to carefully evaluate
motor strength using a novel method of strength measurement in an effort to further evaluate
the impact of depot local anesthetic injection into the adductor canal on physical therapy
and analgesia.

Inclusion Criteria:

1. The subject is scheduled for elective unilateral TKA;

2. The subject is ≥ 18 years and ≤ 80 years;

3. The subject's weight is between 65-130 kg;

4. The subject's primary anesthesia care team has planned for a neuraxial anesthetic
(i.e. spinal, epidural or combined-spinal epidural);

5. The patient agrees to receive an adductor canal block;

6. American Society of Anesthesiologists class 1-3.

Exclusion Criteria:

1. Subject is < 18 years of age or >80 years of age;

2. Subject is non-English speaking;

3. Subject is known or believed to be pregnant;

4. Subject is a prisoner;

5. Subject has impaired decision-making capacity per discretion of the Investigator;

6. Symptomatic untreated gastroesophageal reflux or otherwise at risk for perioperative
aspiration;

7. Any condition for which the primary anesthesia care team deems neuraxial anesthesia
inappropriate;

8. Significant pre-existing neuropathy on the operative limb;

9. Significant renal, cardiac or hepatic disease per discretion of the investigator;

10. American Society of Anesthesiologists class 4-5;

11. Known hypersensitivity and/or allergies to local anesthetics;

12. Chronic Opioid Use (daily or almost daily use of opioids for > 3 months).