Peripheral Nerve Blocks vs Periarticular Local Anesthetic Injection for Total Knee Arthroplasty (TKA)

• Sponsor: Mayo Clinic (Other)
• Overall Status: Completed
• CT.gov ID: NCT02223364
• Collaborator: (none)
• Enrollment: 165
• Location: 1
• Arms: 3
• Duration (Months): 24
• Patients Per Site Per Month: 6.9

Study Details

Study Description

Brief Summary

The purpose of this study is to find a better way to make patients comfortable after their knee surgery. The investigators compared three ways of providing pain relief, either by use of a nerve block at the femoral and sciatic nerve areas, or with actual injections in the surgical joint area with one of two different medicines, either ropivacaine or liposomal bupivacaine (Exparel®). The hypothesis was that the nerve block at the femoral and sciatic nerve areas would result in lower pain scores and opioid consumption than either of the two injections in the surgical joint area.

Condition or Disease	Intervention/Treatment	Phase
Total Knee Arthroplasty	Drug: Peripheral nerve blocks with Bupivacaine; Drug: Intra articular injection with Ropivacaine; Drug: Intra articular injection with liposomal bupivacaine	Phase 4

Study Design

• Study Type: Interventional
• Actual Enrollment: 165 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: Prospective, Randomized, Controlled Trial Comparing Continuous Femoral and Single Injection Sciatic Peripheral Nerve Blocks vs Periarticular Injection With Ropivacaine or Liposomal Bupivacaine (Exparel) on Patients Undergoing Total Knee Arthroplasty
• Study Start Date: Jul 1, 2014
• Actual Primary Completion Date: Jul 1, 2016
• Actual Study Completion Date: Jul 1, 2016

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Peripheral Nerve Block (PNB) This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	Drug: Peripheral nerve blocks with Bupivacaine; Subjects received Bupivacaine 0.5% preoperatively, then Bupivacaine 0.2% upon post anesthesia care unit (PACU) arrival via femoral nerve block, then Bupivacaine 0.25% via single-injection sciatic nerve.; Other Names: Marcaine Sensorcaine
Active Comparator: Ropivacaine (PAI-R) This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	Drug: Intra articular injection with Ropivacaine; Subjects received an intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Ropivacaine dose depended upon body weight: 50-74.9 kg: 200 mg, 75-99.9 kg: 300 mg, 100-125 kg: 400 mg.; Other Names: Naropin
Active Comparator: Liposomal Bupivacaine (PAI-L) This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	Drug: Intra articular injection with liposomal bupivacaine; Subjects received an intra articular injection with liposomal bupivacaine, a total volume of 120 mL injected in the periarticular structures by the surgeon. Patients weighing 50-125 kg received 266mg of Liposomal Bupivacaine.; Other Names: Exparel

Outcome Measures

Primary Outcome Measures

1. Maximum Pain Post-Operative Day (POD) 1 (Morning) [Post-Operative Day 1, approximately 6 am to 12:00 pm]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

Secondary Outcome Measures

1. Average Pain Post-Postanesthesia Care Unit (PACU) [Post-operative Day 0, approximately 12 pm to 12 am]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

2. Maximum Pain Post-PACU [Post-operative Day 0, approximately 12 pm to 12 am]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

3. Average Pain POD 1 (24 Hours) [POD 1, approximately 12 am to 12 am next day]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

4. Maximum Pain POD 1 (24 Hours) [POD 1, approximately 12 am to 12 am next day]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

5. Average Pain POD 2 (24 Hours) [POD 2, approximately 12 am to 12 am next day]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

6. Maximum Pain POD 2 (24 Hours) [POD 2, approximately 12 am to 12 am next day]

   Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.

7. Preoperative Daily Opioid Use [baseline]

   Opioid consumption will be documented in the patient electronic medical record by the nursing staff caring for the patient.

8. Intraoperative Opioid Use [During the procedure, approximately 2 hours after start of the procedure]

   Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.

9. PACU Opioid Use [Approximately 2 hours after entry in PACU]

   Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.

10. POD 0 Post-PACU Opioid Use [POD 0, approximately 12 pm to 12 am]

    Additional opioid medications that were taken by subjects (recorded at the same time as the time points for measuring pain). Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.

11. POD 1 Opioid Use [POD 1, approximately 12 am to 12 am next day]

    Additional opioid medications that were taken by subjects (recorded at the same time as the time points for measuring pain). Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.

12. POD 2 Opioid Use [POD 2, approximately 12 am to 12 am next day]

    Additional opioid medications that were taken by subjects (recorded at the same time as the time points for measuring pain). Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.

13. Hospital Length of Stay [Approximately 3 days]

    The hospital length of stay was measured from the date of admittance until the date of discharge.

14. Balance Testing on Operative Leg Using Unipedal Stance Time [baseline, approximately 12 weeks]

    In order to measure clinical balance, unipedal stance time (UST) was collected as an indicator of balance and fall risk. Timing (in seconds) began upon withdrawal of support and continued until the uplifted foot returned to the floor, the subject required support, or if the subject reached a time limit of 30 seconds. The best performance of three repetitions was recorded for analysis. Normative values for the UST are available. A UST threshold of 30 seconds yields a sensitivity of 95% and a specificity of 58% in identifying those with a history of falls. The first five seconds of unipedal stance is indicative of dynamic balance; inability to maintain unipedal stance for five seconds is a significant predictor of injurious falls.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years and Older
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

1. Adult patients with an American Society of Anesthesiologists (ASA) physiological status I-III

2. Patients presenting for unilateral primary total knee replacement.

3. No focal neurologic deficit of the surgical lower extremity.

4. Cognitively intact with the ability to sign informed consent

Exclusion Criteria:

1. Chronic pain syndromes such as fibromyalgia or complex regional pain syndrome

2. History of long term use of daily opioids (>1 months) with oral morphine equivalent (OME) >5mg/day.

3. Body mass index (BMI) > 40 kg/m2

4. Allergies to medications used in this study such as: fentanyl, hydromorphone, ketorolac, ibuprofen, acetaminophen, local anesthetics, oxycodone, OxyContin, tramadol, ondansetron, droperidol, or dexamethasone, celecoxib

5. Major systemic medical problems such as:

• Severe renal disorder defined as glomerular filtration rate (GFR) <50 units/m2

• Cardiovascular disorders defined as congestive heart failure (CHF) New York Heart Association (NYHA) class III-IV

• Severe hepatic disorder defined as current or past diagnosis of acute/subacute necrosis liver, acute hepatic failure, chronic liver disease, cirrhosis (primary biliary cirrhosis), fatty liver, chronic hepatitis/toxic hepatitis, liver abscess, hepatic coma, hepatorenal syndrome, other disorders of liver.

1. Impaired cognitive function or inability to understand the study protocol

2. Contraindication to a regional anesthesia technique (e.g., preexisting neuropathy in the operative extremity, coagulopathy [platelets < 100,000, International Normalized Ratio (INR) >1.5], refusal, etc.).

3. Previous contralateral knee replacement managed with regional or periarticular injection

4. Unable to follow-up at the 3 month interval at Mayo Clinic in Rochester, Minnesota

5. Pregnancy or breast feeding (women of child-bearing potential, must have a negative pregnancy test)

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Mayo Clinic in Rochester	Rochester	Minnesota	United States	55905

Sponsors and Collaborators

• Mayo Clinic

Investigators

• Principal Investigator: Sandra Kopp, MD, Mayo Clinic

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Sandra (Sandy) L. Kopp, M.D., Associate Professor of Anesthesiology, Mayo Clinic
• ClinicalTrials.gov Identifier: NCT02223364
• Other Study ID Numbers: 14-002083
• First Posted: Aug 22, 2014
• Last Update Posted: Aug 31, 2017
• Last Verified: Aug 1, 2017

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Additional relevant MeSH terms: Bupivacaine; Ropivacaine

Study Results

Participant Flow

Recruitment Details	Subjects were recruited at Mayo Clinic in Rochester, Minnesota from October 2014 to December 2015.

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Period Title: Overall Study
STARTED	55	55	55
COMPLETED	50	55	52
NOT COMPLETED	5	0	3

Baseline Characteristics

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)	Total
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	Total of all reporting groups
Overall Participants	50	55	52	157
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	67 (9)	68 (8)	67 (8)	67.7 (8.8)
Sex: Female, Male (Count of Participants)
Female	25 50%	34 61.8%	27 51.9%	86 54.8%
Male	25 50%	21 38.2%	25 48.1%	71 45.2%
Region of Enrollment (Count of Participants)
United States	50 100%	55 100%	52 100%	157 100%

Outcome Measures

1. Primary Outcome

Title	Maximum Pain Post-Operative Day (POD) 1 (Morning)
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	Post-Operative Day 1, approximately 6 am to 12:00 pm

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [units on a scale]	3	4	4.5

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.144
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.016
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.196
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

2. Secondary Outcome

Title	Average Pain Post-Postanesthesia Care Unit (PACU)
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	Post-operative Day 0, approximately 12 pm to 12 am

Outcome Measure Data

Analysis Population Description

Intent-to-Treat analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [units on a scale]	0.6	1.7	2.4

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.003
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.001
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.021
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

3. Secondary Outcome

Title	Maximum Pain Post-PACU
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	Post-operative Day 0, approximately 12 pm to 12 am

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [units on a scale]	1	4	5

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.001
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.001
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.257
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

4. Secondary Outcome

Title	Average Pain POD 1 (24 Hours)
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	POD 1, approximately 12 am to 12 am next day

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [units on a scale]	2.5	3.5	3.7

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.059
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.005
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.214
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

5. Secondary Outcome

Title	Maximum Pain POD 1 (24 Hours)
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	POD 1, approximately 12 am to 12 am next day

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [units on a scale]	5.5	6	6

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.189
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.043
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.357
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

6. Secondary Outcome

Title	Average Pain POD 2 (24 Hours)
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	POD 2, approximately 12 am to 12 am next day

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis. For POD 2, data are missing for 5 subjects (1 on Peripheral Nerve Block (PNB) arm, 1 on Ropivacaine (PAI-R) arm, and 3 on Liposomal Bupivacaine (PAI-L) arm).

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	49	54	49
Median (Inter-Quartile Range) [units on a scale]	3.3	3.2	3.5

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.958
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.203
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.132
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

7. Secondary Outcome

Title	Maximum Pain POD 2 (24 Hours)
Description	Pain was measured on a 1-10 numeric pain rating scale (NRS) with 0=no pain, and 10=worst pain imaginable.
Time Frame	POD 2, approximately 12 am to 12 am next day

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis. For POD 2, data are missing for 5 subjects (1 on PNB arm, 1 on PAI-R arm, and 3 on PAI-L arm).

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	49	54	49
Median (Inter-Quartile Range) [units on a scale]	5	6	6

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.493
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.299
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.797
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

8. Secondary Outcome

Title	Preoperative Daily Opioid Use
Description	Opioid consumption will be documented in the patient electronic medical record by the nursing staff caring for the patient.
Time Frame	baseline

Outcome Measure Data

Analysis Population Description

Intent-to-Treat Analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [mg oral morphine equivalents (OME)]	15	15	15

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.571
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.991
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.496
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

9. Secondary Outcome

Title	Intraoperative Opioid Use
Description	Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.
Time Frame	During the procedure, approximately 2 hours after start of the procedure

Outcome Measure Data

Analysis Population Description

Intent-to-treat analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [mg OME]	10	10	10

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.807
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.171
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.104
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

10. Secondary Outcome

Title	PACU Opioid Use
Description	Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.
Time Frame	Approximately 2 hours after entry in PACU

Outcome Measure Data

Analysis Population Description

Intent-to-treat analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [mg OME]	0	0	0

11. Secondary Outcome

Title	POD 0 Post-PACU Opioid Use
Description	Additional opioid medications that were taken by subjects (recorded at the same time as the time points for measuring pain). Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.
Time Frame	POD 0, approximately 12 pm to 12 am

Outcome Measure Data

Analysis Population Description

Intent-to-treat

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [mg OME]	0	8	15

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.012
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	<0.001
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.293
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

12. Secondary Outcome

Title	POD 1 Opioid Use
Description	Additional opioid medications that were taken by subjects (recorded at the same time as the time points for measuring pain). Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.
Time Frame	POD 1, approximately 12 am to 12 am next day

Outcome Measure Data

Analysis Population Description

Intent-to-treat analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [mg OME]	26	38	45

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.202
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.007
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.148
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

13. Secondary Outcome

Title	POD 2 Opioid Use
Description	Additional opioid medications that were taken by subjects (recorded at the same time as the time points for measuring pain). Opioid consumption was documented in the patient electronic medical record by the nursing staff caring for the patient.
Time Frame	POD 2, approximately 12 am to 12 am next day

Outcome Measure Data

Analysis Population Description

Intent-to-treat analysis. For POD 2, data are missing for 5 subjects (1 on PNB arm, 1 on PAI-R arm, and 3 on PAI-L arm).

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	49	54	49
Median (Inter-Quartile Range) [mg OME]	23	15	23

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.933
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.169
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.126
	Comments
	Method	Wilcoxon (Mann-Whitney)
	Comments

14. Secondary Outcome

Title	Hospital Length of Stay
Description	The hospital length of stay was measured from the date of admittance until the date of discharge.
Time Frame	Approximately 3 days

Outcome Measure Data

Analysis Population Description

Intent-to-treat analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
Median (Inter-Quartile Range) [days]	2	2	2

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB), Ropivacaine (PAI-R), Liposomal Bupivacaine (PAI-L)
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.768
	Comments
	Method	Kruskal-Wallis
	Comments

15. Secondary Outcome

Title	Balance Testing on Operative Leg Using Unipedal Stance Time
Description	In order to measure clinical balance, unipedal stance time (UST) was collected as an indicator of balance and fall risk. Timing (in seconds) began upon withdrawal of support and continued until the uplifted foot returned to the floor, the subject required support, or if the subject reached a time limit of 30 seconds. The best performance of three repetitions was recorded for analysis. Normative values for the UST are available. A UST threshold of 30 seconds yields a sensitivity of 95% and a specificity of 58% in identifying those with a history of falls. The first five seconds of unipedal stance is indicative of dynamic balance; inability to maintain unipedal stance for five seconds is a significant predictor of injurious falls.
Time Frame	baseline, approximately 12 weeks

Outcome Measure Data

Analysis Population Description

Intent-to-treat analysis

Arm/Group Title	Peripheral Nerve Block (PNB)	Ropivacaine (PAI-R)	Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.	This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.	This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
Measure Participants	50	55	52
baseline	24	16	17
12 weeks	20	30	23

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Peripheral Nerve Block (PNB)
	Comments	Within group comparison of baseline and 3 months (approximately 12 weeks)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.623
	Comments
	Method	Regression, Cox
	Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Ropivacaine (PAI-R)
	Comments	Within group comparison of baseline and 3 months (approximately 12 weeks)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.001
	Comments
	Method	Regression, Cox
	Comments

Statistical Analysis 3

Statistical Analysis Overview	Comparison Group Selection	Liposomal Bupivacaine (PAI-L)
	Comments	Within group comparison of baseline and three months (approximately 12 weeks)
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.048
	Comments
	Method	Regression, Cox
	Comments

Adverse Events

Time Frame	3 months
Arm/Group Title	Peripheral Nerve Block (PNB)		Ropivacaine (PAI-R)		Liposomal Bupivacaine (PAI-L)
Arm/Group Description	This group received a continuous femoral nerve block and a single injection sciatic nerve block consisting of the following: Peripheral nerve blocks with Bupivacaine.		This group received intra articular injection with Ropivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.		This group received Intra articular injection with liposomal bupivacaine, a total volume of 120 milliliters (mL) injected in the periarticular structures by the surgeon. Following the current, standardized practice for periarticular infiltration, approximately 30 - 40 mL of solution was injected into the posterior capsule just prior to cementing the implants in place and 40 - 50 mL of solution injected into the medial and lateral retinaculum while the cement was hardening and prior to deflation of the tourniquet. The remaining volume of approximately 40 mL was injected into the quadriceps tendon and subcutaneous tissue prior to skin closure.
All Cause Mortality
	Peripheral Nerve Block (PNB)		Ropivacaine (PAI-R)		Liposomal Bupivacaine (PAI-L)
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/50 (0%)		0/55 (0%)		0/52 (0%)
Serious Adverse Events
	Peripheral Nerve Block (PNB)		Ropivacaine (PAI-R)		Liposomal Bupivacaine (PAI-L)
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/50 (0%)		0/55 (0%)		0/52 (0%)
Other (Not Including Serious) Adverse Events
	Peripheral Nerve Block (PNB)		Ropivacaine (PAI-R)		Liposomal Bupivacaine (PAI-L)
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	2/50 (4%)		3/55 (5.5%)		3/52 (5.8%)
General disorders
Fall	2/50 (4%)	2	1/55 (1.8%)	1	1/52 (1.9%)	1
Rapid Response Team	0/50 (0%)	0	1/55 (1.8%)	1	1/52 (1.9%)	1
Additional surgery	1/50 (2%)	1	0/55 (0%)	0	0/52 (0%)	0
Infections and infestations
Superficial wound infection	2/50 (4%)	2	2/55 (3.6%)	2	2/52 (3.8%)	2
Nervous system disorders
Nerve Injury	2/50 (4%)	2	0/55 (0%)	0	0/52 (0%)	0

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.