Postoperative Pain, Knee Replacement Arthroplasty
Conditions
Brief summary
The purpose of this study is to compare two methods of postoperative pain management in patients undergoing total knee replacement.
Detailed description
Patients undergoing total knee replacement will be assigned at random to receive one of two methods of postoperative pain management. Patients assigned to nerve block will receive regional anesthetic nerve block using an indwelling femoral nerve catheter and a single shot sciatic nerve block. Patients assigned to periarticular injection will receive periarticular local injection into the periarticular soft tissues at the time of knee replacement using a combination of ropivacaine, epinephrine, ketorolac, and morphine sulphate. Additionally, all patients will be given a standardized combination of oral analgesic medications preoperatively and postoperatively. All patients will receive a posterior stabilized total knee replacement through an medial parapatellar approach.
Interventions
DRUGNerve Block
Regional anesthetic nerve block using an indwelling femoral nerve catheter and a single shot sciatic nerve block using 0.5% ropivacaine.
Periarticular local injection into the periarticular soft tissues at the time of knee replacement using a combination of ropivacaine, epinephrine, ketorolac, and morphine sulphate. Subjects in this arm received the injection combination based on three subject weight categories.
Sponsors
Mark J. Spangehl, M.D.
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 79 Years
Healthy volunteers
No
Inclusion criteria
* Unilateral primary total knee replacement. * Weight 50-125 kg. * Age 18-79 years. * Intact neurological exam to the surgical lower extremity. * Cognitively intact with ability to sign informed consent.
Exclusion criteria
* Renal insufficiency with creatinine \>1.5 mg/dL. * Allergy to medication used in the study. * Using narcotic medication prior to surgery (morphine equivalents \>=20 mg/day for \>7 days.) * Prior open knee surgery with regional anesthesia or periarticular injection for post-operative pain management.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Post-Operative Pain | Afternoon on post-operative Day 1, approximately 14:00 | Pain was measured using a linear analog scale for pain, with a scale from 0 (no pain) to 10 points (worst possible pain). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain Scores in the Per-protocol Subset (Participants Who Received the Allocated Treatment) | Afternoon on post-operative Day 1, approximately 14:00 | Pain was measured using a linear analog scale for pain, with a scale from 0 (no pain) to 10 points (worst possible pain). |
| Narcotic Use | Intraoperative, Day of surgery, Post-Operative Day 1, Post-Operative Day 2 | Use of additional narcotic medications (as needed), measured in morphine equivalents. |
| Straight-leg Raise | Day 1 morning (AM), Day 1 afternoon (PM), Day 2 morning, Day 2 afternoon | Post-operative quadriceps function was measured by the number of participants who could perform a straight-leg raise. |
| Length of Stay in Hospital | Approximately 2 days after surgery | Length of stay data were calculated from the medical record. |
| Number of Subjects Who Experienced Neurological Changes Postoperatively | 6 weeks postoperative | Participants were questioned at the 6 weeks follow-up visit regarding any neurological changes that were not present preoperatively. |
Countries
United States
Participant flow
Recruitment details
Subjects were recruited from Mayo Clinic, Phoenix, Arizona from September 2010 to February 2013.
Participants by arm
| Arm | Count |
|---|---|
| Nerve Block Preoperative femoral block with indwelling femoral catheter and a single shot sciatic block.
Nerve Block: Regional anesthetic nerve block using an indwelling femoral nerve catheter and a single shot sciatic nerve block using 0.5% ropivacaine. | 79 |
| Periarticular Injection Injection combination prior to skin closure.
Periarticular Injection: Periarticular local injection into the periarticular soft tissues at the time of knee replacement using a combination of ropivacaine, epinephrine, ketorolac, and morphine sulphate. Subjects in this arm received the injection combination based on three subject weight categories. | 81 |
| Total | 160 |
Baseline characteristics
| Characteristic | Nerve Block | Periarticular Injection | Total |
|---|---|---|---|
| Age, Continuous | 67.8 years STANDARD_DEVIATION 7.9 | 67.7 years STANDARD_DEVIATION 7.2 | 67.7 years STANDARD_DEVIATION 7.6 |
| Region of Enrollment United States | 79 participants | 81 participants | 160 participants |
| Sex: Female, Male Female | 41 Participants | 48 Participants | 89 Participants |
| Sex: Female, Male Male | 38 Participants | 33 Participants | 71 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 55 / 79 | 54 / 81 |
| serious Total, serious adverse events | 4 / 79 | 0 / 81 |
Outcome results
Primary
Post-Operative Pain
Pain was measured using a linear analog scale for pain, with a scale from 0 (no pain) to 10 points (worst possible pain).
Time frame: Afternoon on post-operative Day 1, approximately 14:00
Population: Intention to treat analysis
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Nerve Block | Post-Operative Pain | 2.9 units on a scale | Standard Deviation 2.4 |
| Periarticular Injection | Post-Operative Pain | 3.0 units on a scale | Standard Deviation 2.2 |
p-value: 0.76t-test, 2 sided
p-value: 0.59Wilcoxon (Mann-Whitney)
Secondary
Length of Stay in Hospital
Length of stay data were calculated from the medical record.
Time frame: Approximately 2 days after surgery
Population: The number of participants analyzed were different than the baseline values for the arms because data were not available for some participants.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Nerve Block | Length of Stay in Hospital | 2.84 days | Standard Deviation 1.34 |
| Periarticular Injection | Length of Stay in Hospital | 2.44 days | Standard Deviation 0.65 |
Comparison: Comparison between the arms for length of stay in the hospital.p-value: 0.02t-test, 2 sided
Secondary
Narcotic Use
Use of additional narcotic medications (as needed), measured in morphine equivalents.
Time frame: Intraoperative, Day of surgery, Post-Operative Day 1, Post-Operative Day 2
Population: Intention to treat analysis
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Nerve Block | Narcotic Use | Intraoperative | 17.4 mg | Standard Deviation 10.1 |
| Nerve Block | Narcotic Use | Day of Surgery | 4.6 mg | Standard Deviation 9.1 |
| Nerve Block | Narcotic Use | Post-Operative Day 1 | 43.0 mg | Standard Deviation 29 |
| Nerve Block | Narcotic Use | Post-Operative Day 2 | 33.0 mg | Standard Deviation 28 |
| Periarticular Injection | Narcotic Use | Post-Operative Day 2 | 30.0 mg | Standard Deviation 29 |
| Periarticular Injection | Narcotic Use | Intraoperative | 23.6 mg | Standard Deviation 8.5 |
| Periarticular Injection | Narcotic Use | Post-Operative Day 1 | 49.0 mg | Standard Deviation 29 |
| Periarticular Injection | Narcotic Use | Day of Surgery | 11.7 mg | Standard Deviation 13.1 |
Comparison: Comparison of arms for intraoperative narcotic use.p-value: <0.001t-test, 2 sided
Comparison: Comparison of arms for narcotic use on day of surgery as needed.p-value: <0.001t-test, 2 sided
Comparison: Comparison of arms for narcotic use on post operative day 1 as needed.p-value: 0.17t-test, 2 sided
Comparison: Comparison of arms for narcotic use on post operative day 2 as needed.p-value: 0.51t-test, 2 sided
Secondary
Number of Subjects Who Experienced Neurological Changes Postoperatively
Participants were questioned at the 6 weeks follow-up visit regarding any neurological changes that were not present preoperatively.
Time frame: 6 weeks postoperative
Population: The number of participants analyzed in the nerve block arm varied because data were not available for all participants in all neurological categories. The sample size for the periarticular injection arm was 79 because neurological data were not collected on 2 participants.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Nerve Block | Number of Subjects Who Experienced Neurological Changes Postoperatively | Common peroneal nerve (nerve block n=78) | 6 participants |
| Nerve Block | Number of Subjects Who Experienced Neurological Changes Postoperatively | Tibial nerve (nerve block n=78) | 2 participants |
| Nerve Block | Number of Subjects Who Experienced Neurological Changes Postoperatively | Femoral, peroneal, or tibial (nerve block n=77) | 9 participants |
| Nerve Block | Number of Subjects Who Experienced Neurological Changes Postoperatively | Femoral nerve (nerve block n=77) | 1 participants |
| Periarticular Injection | Number of Subjects Who Experienced Neurological Changes Postoperatively | Femoral, peroneal, or tibial (nerve block n=77) | 1 participants |
| Periarticular Injection | Number of Subjects Who Experienced Neurological Changes Postoperatively | Common peroneal nerve (nerve block n=78) | 0 participants |
| Periarticular Injection | Number of Subjects Who Experienced Neurological Changes Postoperatively | Femoral nerve (nerve block n=77) | 0 participants |
| Periarticular Injection | Number of Subjects Who Experienced Neurological Changes Postoperatively | Tibial nerve (nerve block n=78) | 1 participants |
Comparison: Comparison between arms for femoral nerve.p-value: 0.49t-test, 2 sided
Comparison: Comparison between arms for common peroneal nerve.p-value: 0.01t-test, 2 sided
Comparison: Comparison between arms for tibial nerve.p-value: 0.62t-test, 2 sided
Comparison: Comparison between arms for femoral, peroneal, or tibial nerves.p-value: 0.009t-test, 2 sided
Secondary
Pain Scores in the Per-protocol Subset (Participants Who Received the Allocated Treatment)
Pain was measured using a linear analog scale for pain, with a scale from 0 (no pain) to 10 points (worst possible pain).
Time frame: Afternoon on post-operative Day 1, approximately 14:00
Population: In the nerve block arm 5 subjects were excluded (3 subjects were not treated as planned, and 1 subject received a sciatic catheter instead of a single injection, and 1 subject previously had a nerve block procedure.) In the periarticular injection arm 4 patients were excluded (3 subjects were not treated as planned, and 1 subject was too heavy.)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Nerve Block | Pain Scores in the Per-protocol Subset (Participants Who Received the Allocated Treatment) | 2.9 units on a scale | Standard Deviation 2.4 |
| Periarticular Injection | Pain Scores in the Per-protocol Subset (Participants Who Received the Allocated Treatment) | 3.1 units on a scale | Standard Deviation 2.2 |
p-value: 0.78t-test, 2 sided
p-value: 0.58Wilcoxon (Mann-Whitney)
Secondary
Straight-leg Raise
Post-operative quadriceps function was measured by the number of participants who could perform a straight-leg raise.
Time frame: Day 1 morning (AM), Day 1 afternoon (PM), Day 2 morning, Day 2 afternoon
Population: The number of participants analyzed varied at each category time point because either data points were missing for participants, or as the condition of the participants improved, they were discharged from the hospital. Number of participants per arm for each time point is shown in each category label.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Nerve Block | Straight-leg Raise | Day 1 AM (Nerve Block=78, Injection=80) | 19 participants |
| Nerve Block | Straight-leg Raise | Day 1 PM (Nerve Block=76, Injection=78) | 21 participants |
| Nerve Block | Straight-leg Raise | Day 2 AM (Nerve Block=78, Injection=79) | 52 participants |
| Nerve Block | Straight-leg Raise | Day 2 PM (Nerve Block=69, Injection=51) | 57 participants |
| Periarticular Injection | Straight-leg Raise | Day 2 PM (Nerve Block=69, Injection=51) | 42 participants |
| Periarticular Injection | Straight-leg Raise | Day 1 AM (Nerve Block=78, Injection=80) | 63 participants |
| Periarticular Injection | Straight-leg Raise | Day 2 AM (Nerve Block=78, Injection=79) | 69 participants |
| Periarticular Injection | Straight-leg Raise | Day 1 PM (Nerve Block=76, Injection=78) | 63 participants |
Comparison: Comparison between arms for postoperative day 1 morning.p-value: <0.001t-test, 2 sided
Comparison: Comparison between arms for postoperative day 1 afternoon.p-value: <0.001t-test, 2 sided
Comparison: Comparison between arms for postoperative day 2 morning.p-value: 0.002t-test, 2 sided
Comparison: Comparison between arms for postoperative day 2 afternoon.p-value: 0.97t-test, 2 sided