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Assessing musculoskeletal performance of the back extensors following a single-level microdiscectomy
Sean P Flanagan1, Kornelia Kulig
1Department of Kinesiology, California State University, Northridge, Northridge, CA 91330-8287, USA. sean.flanagan@csun.edu
Study Design:
A descriptive and exploratory investigation of lumbar extensor performance in persons with a recent history of single-level microdiscectomy.
Objective:
To provide a justification for and outline the procedure of assessing lumbar extensor musculature performance.
Background:
The time of holding an unsupported trunk horizontally, also called the Sorensen test (ST), is often used to test the lumbar extensor endurance of healthy and patient populations, but may need to be modified for some patients.
Methods And Measures:
Sixty-eight participants completed a modified ST procedure, along with several questionnaires and performance measures, approximately 4 to 6 weeks after a single-level microdiscectomy. Participants were classified as either able to complete or unable to complete the final position of the modified ST procedure (trunk horizontal).
Results:
Fifty-one point five percent of the participants could not attain the final position of the modified ST procedure due to either pain or perceived exertion. Those who could not attain the final position of the modified ST procedure had significantly lower scores (compared to those who could) on most measures. A majority (78.8%) of the participants in this study who were unable to complete the ST were correctly classified using the Fear-Avoidance Belief Questionnaire Work Subscale and a 24-hour activity questionnaire.
Conclusion:
The ability to attain the final position of the modified ST procedure was closely associated with fear-avoidance beliefs and physical activity level, suggesting that this test may be too intense (either real or perceived) for many patients within 4 to 6 weeks following a single-level microdiscectomy.