Total Knee Arthroplasty
Conditions
Keywords
Total Knee Replacement, Regional Anesthesia, Quadriceps, Muscle Strength, Muscle Strength Dynamometer, Quadriceps muscle strength after regional anesthesia for TKA
Brief summary
Currently, the regional anesthetic standard of care for total knee replacement surgery is combined spinal/epidural, with or without a femoral nerve block, or FNB. Lasting approximately 18 hours, the FNB works by numbing the femoral nerve (and its branches), which is the major nerve controlling the knee joint. The femoral nerve also provides movement and sensation. While this regional anesthetic technique offers significant postoperative pain relief, it is possible that it may cause muscle weakness and increase patients' recovery time. Hence there is a need for an alternative technique, one that may help minimize postoperative pain as effectively as the FNB, while not causing weakness of the quadriceps muscle. The saphenous nerve, a branch of the femoral nerve, provides sensation to the knee. Thus it is hypothesized that by blocking or anesthetizing the saphenous nerve with local anesthetic closer to where it branches off, the area around and below the knee will feel numb. Yet unlike with the FNB, the quadriceps muscle itself will still be able to function. Patients will be randomized to receive FNB or saphenous nerve block. Quadriceps strength will be tested using a dynamometer before surgery (baseline), 6-8 hours following anesthesia administration, and on postoperative days 1 and 2. It is hypothesized that patients who receive FNB will experience a 50% decrease in quadriceps strength compared to baseline.
Interventions
PROCEDUREStudy Group: Experimental
The study group will receive the saphenous nerve block, at the level of the adductor canal. The block will be under ultrasound guidance. The local anesthetic will be 15 ml of 0.5% bupivicaine. The study group will also receive a combined spinal epidural, with 2.5 ml of 0.5% bupivacaine as the spinal agent. Additional drugs include anti-emetics, specifically Ondansetron (4 mg).
PROCEDUREControl Group
The control group will receive the femoral nerve block. The block will be under ultrasound guidance. The local anesthetic will be 30 ml of 0.25% bupivicaine. The control group will also receive a combined spinal epidural, with 2.5 ml of 0.5% bupivacaine as the spinal agent. Additional drugs include anti-emetics, specifically Ondansetron (4 mg).
Sponsors
Hospital for Special Surgery, New York
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* All patients ages 18-90 undergoing primary unilateral total knee arthroplasty * Planned use of neuraxial anesthesia * Ability to follow study protocol * American Society of Anesthesiology (ASA) Class 1-3
Exclusion criteria
* Contraindication to a spinal or epidural anesthetic * Chronic opioid use (defined as daily or almost daily use of opioids for \>3 months) * Hypersensitivity and/or allergy to local anesthetics * Intraoperative use of any volatile anesthetic * Patients with a pre-existing neuropathy on the operative limb * Contraindication to a femoral nerve block or saphenous nerve block * Allergy to any of the study medications * Non-English speaking patients
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Quadriceps Muscle Strength | 48 hours following administration of anesthesia. | Measurements were made by a handheld dynamometer while patients perform isometric exercises. Results are presented in kilogram-force (kgF) units. One kgF is equal to 9.80665 N. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Total Opioid Usage | Postoperative day 4. | Opioid consumption data were collected and converted to oral morphine equivalents. |
| NRS Pain Scores at Rest | Postoperative day 4. | Patients rated pain on a scale of 0-10, with 0 representing no pain and 10 representing worst pain. |
| Patient Satisfaction With the Nerve Block. | 24 hours following administration of anesthesia. | Patient satisfaction was measured on a 0-10 scale (0=not satisfied; 10=very satisfied). |
| Incidence of Postoperative Complications. | Postoperative day 4. | — |
| Total Length of Hospital Stay | Total length of hospital stay | — |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Experimental Saphenous (Adductor Canal) Nerve Block
Study Group: Experimental: The study group will receive the saphenous nerve block, at the level of the adductor canal. The block will be under ultrasound guidance. The local anesthetic will be 15 ml of 0.5% bupivicaine. The study group will also receive a combined spinal epidural, with 2.5 ml of 0.5% bupivacaine as the spinal agent. Additional drugs include anti-emetics, specifically Ondansetron (4 mg). | 46 |
| Control Femoral Nerve Block
Control Group: The control group will receive the femoral nerve block. The block will be under ultrasound guidance. The local anesthetic will be 30 ml of 0.25% bupivicaine. The control group will also receive a combined spinal epidural, with 2.5 ml of 0.5% bupivacaine as the spinal agent. Additional drugs include anti-emetics, specifically Ondansetron (4 mg). | 47 |
| Total | 93 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Known neuropathy | 1 | 0 |
Baseline characteristics
| Characteristic | Experimental | Control | Total |
|---|---|---|---|
| Age, Continuous | 68.0 years STANDARD_DEVIATION 9.4 | 67.6 years STANDARD_DEVIATION 11.3 | 67.8 years STANDARD_DEVIATION 10.4 |
| Region of Enrollment United States | 46 participants | 47 participants | 93 participants |
| Sex: Female, Male Female | 24 Participants | 29 Participants | 53 Participants |
| Sex: Female, Male Male | 22 Participants | 18 Participants | 40 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 47 | 0 / 47 |
| other Total, other adverse events | 0 / 47 | 0 / 47 |
| serious Total, serious adverse events | 0 / 47 | 0 / 47 |
Outcome results
Primary
Quadriceps Muscle Strength
Measurements were made by a handheld dynamometer while patients perform isometric exercises. Results are presented in kilogram-force (kgF) units. One kgF is equal to 9.80665 N.
Time frame: 48 hours following administration of anesthesia.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Experimental | Quadriceps Muscle Strength | 7.3 kilogram-force | Standard Deviation 5.4 |
| Control | Quadriceps Muscle Strength | 2.2 kilogram-force | Standard Deviation 3.8 |
Secondary
Incidence of Postoperative Complications.
Time frame: Postoperative day 4.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Experimental | Incidence of Postoperative Complications. | 0 Participants |
| Control | Incidence of Postoperative Complications. | 0 Participants |
Secondary
NRS Pain Scores at Rest
Patients rated pain on a scale of 0-10, with 0 representing no pain and 10 representing worst pain.
Time frame: Postoperative day 4.
Population: One patient was excluded at the time of analysis, and the remaining 93 patients were included in the analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Experimental | NRS Pain Scores at Rest | 1.7 units on a scale | Standard Deviation 1.9 |
| Control | NRS Pain Scores at Rest | 0.9 units on a scale | Standard Deviation 1.8 |
Secondary
Patient Satisfaction With the Nerve Block.
Patient satisfaction was measured on a 0-10 scale (0=not satisfied; 10=very satisfied).
Time frame: 24 hours following administration of anesthesia.
Population: One patient was excluded from analysis, and the remaining 93 patients were included.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Experimental | Patient Satisfaction With the Nerve Block. | 8.8 units on a scale | Standard Deviation 1.9 |
| Control | Patient Satisfaction With the Nerve Block. | 9.1 units on a scale | Standard Deviation 1.7 |
Secondary
Total Length of Hospital Stay
Time frame: Total length of hospital stay
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Experimental | Total Length of Hospital Stay | 3.7 days | Standard Deviation 0.8 |
| Control | Total Length of Hospital Stay | 3.6 days | Standard Deviation 0.8 |
Secondary
Total Opioid Usage
Opioid consumption data were collected and converted to oral morphine equivalents.
Time frame: Postoperative day 4.
Population: One patient was excluded from analysis due to a condition. Data from the remaining 93 patients were analyzed.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Experimental | Total Opioid Usage | 36.6 mg | Standard Deviation 17.9 |
| Control | Total Opioid Usage | 35.8 mg | Standard Deviation 20.7 |