Evidence-Based Practice – Issue 6-2015
Low Back and Lower-Limb Muscle Performance in Male and Female Recreational Runners with Low Back Pain
Article. Cai C, Kong PW. Low Back and Lower-Limb muscle performance in male and female recreational runners with chronic low back pain. Journal of Sports and Orthopedic Physical Therapy 2015; 6(45): 437-443.
Purpose. The purpose of this study was to compare lumbar extensor muscle fatigability, lumbar stabilizing muscle activation, and lower limb strength between male and female runners with chronic low back pain.
Study Design. Controlled laboratory cohort study.
Methods.
- Subjects
- Low Back Pain Group: 18 recreational runners (9 male; 9 female) with chronic low back pain
- Age: 27.8 years
- Control Group: 18 recreational runners (9 male; 9 female) without chronic low back pain
- Age: 24.6 years
- Low Back Pain Group: 18 recreational runners (9 male; 9 female) with chronic low back pain
- Data Collection
- Lumbar Extensor Muscle Fatigability – Electromyographic activity of the longissimus and iliocostalis muscles were recorded during the Sorensen Test. The Sorensen test measures fatigue of the lumbar extensors. The patient hangs their torso off the edge of a table with their lower extremity secured to the table. The patient maintains their trunk off the edge of the table, horizontal to the floor for a total 2 minutes.
- Lumbar stabilizing muscle activity – The activity of the transversus abdominis and lumbar multifidus were measured by ultrasound by measuring the difference of muscle thickness at rest and during a straight leg raise.
- Lower-Limb Muscle Isokinetic strength – Isokinetic strength of the knee extensors, hip extensors, and hip flexors was measured with a Biodex machine.
- Data Analysis
- A general linear model was constructed to detect differences in muscle performance between the chronic low back pain group versus the control group.
Results
- Peak knee extensor torque was 12.2% less in the low back pain group
- Male runners with low back pain showed reduced activation of the lumbar multifidus.
- See Table below (click to enlarge)
Clinical Relevance
- Runners with low back pain tend to have lower quadriceps strength.
- Runners with low back pain may also have decreased activation of the lumbar multifidus muscles.
- Treatment and prevention of low back pain in runners should consider exercises that emphasize quadriceps strengthening and activation of lumbar extensor muscles.
