Low Back Pain
Conditions
Brief summary
Rehabilitative Ultrasound Imaging (US) is a procedure used to evaluate skeletal muscle size and function to inform clinical practice. US has been shown to be a reliable and valid tool for measuring changes in trunk muscle (i.e. abdominal and back muscle) size and activity during sub-maximal contractions in younger populations. Younger adults with low back pain as compared with healthy adults without pain demonstrate smaller back muscle size, lower back muscle activity, and greater back muscle asymmetry (differences in right side compared with left side). No trials are published evaluating muscle adaptations using US in response to clinical treatments for low back pain in the older adult population. Increased muscle size and improved muscle symmetry have been reported in younger adults with low back pain who participate in low back stabilization exercises. These exercises use voluntary contractions of the back muscles with prolonged hold times and low loads. Neuromuscular Electrical Stimulation (NMES) is a treatment modality that increases muscle activity when voluntary activity is impaired and increases muscle size. Most studies assessing muscle size and activity in response to NMES have been conducted in the knee muscles (i.e. the quadriceps), while the impact of NMES on the back muscles remains relatively unexplored. Given the potential to evaluate back muscle size and activity with US, this assessment tool may be used to document muscle adaptations to a clinical intervention in older adults with low back pain. The purpose of this study is to conduct a 6-week clinical trial to determine if NMES plus lumbar stabilization exercises (i.e. NMES AND Stabilization Exercises) is superior to lumbar stabilization exercises (i.e. Moist Heat AND Stabilization Exercises) for improving back muscle size, activity, and side-to-side (i.e. right side versus left side) symmetry in older adults with chronic low back pain (i.e. low back pain of greater than 3 months). Muscle size, activity, and symmetry will be assessed using US before and after the treatments to determine if the treatments positively impact muscle. Secondary clinical measures of success will include improvements in physical, psychological, and social function pre- to post-treatment.
Interventions
OTHERNeuromuscular Electrical Stimulation
Neuromuscular Electrical Stimulation (NMES) to the low back muscles (i.e. spinal extensors) will be applied at the parameters previously used in the knee muscles at the maximal tolerable intensity, which results in a full, sustained isometric contraction of the back muscles. Pad placement will be just below the waist line, with 2, 2X2 inch pads, on either side of the spine. Participants will be positioned on their belly with 2 pillows under their stomach to level the spine and secured to a table using a belt that crosses the buttock. The lumbar stabilization program will include exercises targeting the back muscles in three positions: standing, prone (belly), and quadruped (hands and knees).
OTHERMoist Heat
For participants who do not receive NMES, moist heat will be applied for 15 minutes in a position of comfort for the participant. The lumbar stabilization program will include exercises targeting the back muscles in three positions: standing, prone (belly), and quadruped (hands and knees).
Sponsors
University of Delaware
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
60 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
This study will use a sample consisting of 36, English-speaking and English-reading, older male and female adults (ages 60-85 years) with chronic low back pain, i.e. pain of greater than 3 months duration. During the examination, potential participants must have 2/4 of the following for inclusion, based on previous work by Hicks et al, which outlined clinical predictors of success with a trunk muscle stabilization exercise program: 1. Fear-Avoidance Beliefs Questionnaire (FABQ) Physical Activity Sub-Scale score ≥9: The FABQ is a measure of an individual's beliefs regarding the impact of physical activity and work on his/her low back pain. The FABQ is comprised of two sub-scales: physical activity and work. Higher FABQ scores have been shown to predict pain and disability in individuals with chronic low back pain. 2. Aberrant Movement: Aberrant movement may be classified as any one of the following: (1) an instability catch, defined as deviation from the plane of movement during flexion or extension; (2) thigh climbing, which is defined as using the hands and pushing on the thighs to assist in obtaining an upright trunk position; (3) a painful arc of motion, when flexing or returning to upright from a flexed spinal position; or (4) reversal of the lumbopelvic rhythm, where the trunk is first extended and then the hips and pelvis extend to bring the body upright from a flexed position. 3. Posterior-to-Anterior Segmental Hypermobility: The participant will lie on his/her stomach and the examiner will apply a posterior-to-anterior (back-to-front) force over the spinous processes from S1 to T12 (just below the belt-line to the rib cage). The available mobility will be graded hypermobile (too much motion), normal, or hypomobile (too little motion). 4. Positive Prone Instability Test: The participant will lie on his/her stomach with the legs off the edge of the table and the feet resting on the floor. The examiner will apply a posterior-to-anterior pressure at each spinous process (T12-S1). Any provocation of pain will require the participant to lift their legs off the floor while the pressure is reapplied to the painful level. If the pain subsides with elevation of the legs, this is considered a positive test.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Difference in Percent Change From Baseline in L4 Paraspinal Cross-Sectional Area Asymmetry at 6 Weeks Between Intervention Arms | Baseline and 6 Weeks | Percent change (baseline-6 weeks)/baseline X100% was calculated for each participant in each intervention arm and then these differences were compared using a Mann-Whitney U test since data did not meet parametric assumptions. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| NMES AND Stabilization Exercises Neuromuscular Electrical Stimulation and Lumbar Stabilization Exercises
Neuromuscular Electrical Stimulation: Neuromuscular Electrical Stimulation (NMES) to the low back muscles (i.e. spinal extensors) will be applied at the parameters previously used in the knee muscles at the maximal tolerable intensity, which results in a full, sustained isometric contraction of the back muscles. Pad placement will be just below the waist line, with 2, 2X2 inch pads, on either side of the spine. Participants will be positioned on their belly with 2 pillows under their stomach to level the spine and secured to a table using a belt that crosses the buttock.
The lumbar stabilization program will include exercises targeting the back muscles in three positions: standing, prone (belly), and quadruped (hands and knees). | 15 |
| Moist Heat AND Stabilization Exercises Moist Heat and Lumbar Stabilization Exercises
Moist Heat: For participants who do not receive NMES, moist heat will be applied for 15 minutes in a position of comfort for the participant.
The lumbar stabilization program will include exercises targeting the back muscles in three positions: standing, prone (belly), and quadruped (hands and knees). | 19 |
| Total | 34 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Withdrawal by Subject | 3 | 1 |
Baseline characteristics
| Characteristic | NMES AND Stabilization Exercises | Moist Heat AND Stabilization Exercises | Total |
|---|---|---|---|
| Age, Continuous | 71.9 years STANDARD_DEVIATION 7.6 | 71.3 years STANDARD_DEVIATION 7.7 | 71.6 years STANDARD_DEVIATION 7.6 |
| Fear-Avoidance Beliefs Questionnaire-Physical Activity Subscale | 13.7 scores on a scale STANDARD_DEVIATION 4.4 | 15.2 scores on a scale STANDARD_DEVIATION 6.5 | 14.5 scores on a scale STANDARD_DEVIATION 5.7 |
| L4 Paraspinal Cross-Sectional Area Asymmetry | 14.0 percent asymmetry STANDARD_DEVIATION 13.3 | 10.1 percent asymmetry STANDARD_DEVIATION 7.8 | 11.8 percent asymmetry STANDARD_DEVIATION 10.6 |
| Left L4/5 Lumbar Multifidus Activity | 11.1 percentage of activity STANDARD_DEVIATION 5.6 | 12.3 percentage of activity STANDARD_DEVIATION 4.9 | 11.8 percentage of activity STANDARD_DEVIATION 5.2 |
| Left L4 Paraspinal Muscle Size | 11.6 cm2 STANDARD_DEVIATION 2 | 12.0 cm2 STANDARD_DEVIATION 2 | 11.9 cm2 STANDARD_DEVIATION 2 |
| Modified Oswestry Disability Index | 25.5 % STANDARD_DEVIATION 8.7 | 22.2 % STANDARD_DEVIATION 7.9 | 23.6 % STANDARD_DEVIATION 8.3 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 15 Participants | 17 Participants | 32 Participants |
| Region of Enrollment United States | 15 participants | 19 participants | 34 participants |
| Right L4/5 Lumbar Multifidus Activity | 9.5 percentage of activity STANDARD_DEVIATION 6 | 11.8 percentage of activity STANDARD_DEVIATION 4.4 | 10.8 percentage of activity STANDARD_DEVIATION 5.3 |
| Right L4 Paraspinal Muscle Size | 11.1 cm2 STANDARD_DEVIATION 2.1 | 11.4 cm2 STANDARD_DEVIATION 1.8 | 11.2 cm2 STANDARD_DEVIATION 1.9 |
| Sex: Female, Male Female | 7 Participants | 9 Participants | 16 Participants |
| Sex: Female, Male Male | 8 Participants | 10 Participants | 18 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 18 | 0 / 20 |
| other Total, other adverse events | 1 / 18 | 0 / 20 |
| serious Total, serious adverse events | 0 / 18 | 0 / 20 |
Outcome results
Primary
Difference in Percent Change From Baseline in L4 Paraspinal Cross-Sectional Area Asymmetry at 6 Weeks Between Intervention Arms
Percent change (baseline-6 weeks)/baseline X100% was calculated for each participant in each intervention arm and then these differences were compared using a Mann-Whitney U test since data did not meet parametric assumptions.
Time frame: Baseline and 6 Weeks
Population: Analyses were only completed on participants who completed the randomized clinical trial.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| NMES AND Stabilization Exercises | Difference in Percent Change From Baseline in L4 Paraspinal Cross-Sectional Area Asymmetry at 6 Weeks Between Intervention Arms | 0 % change |
| Moist Heat AND Stabilization Exercises | Difference in Percent Change From Baseline in L4 Paraspinal Cross-Sectional Area Asymmetry at 6 Weeks Between Intervention Arms | -17.6 % change |
p-value: 1Wilcoxon (Mann-Whitney)