Affiliations: [a] Applied Kinesiology and Ergonomic Technology
Laboratory, Department of Physical Therapy, The Graduate School, Yonsei
University, Wonju, Korea
Note: [] Corresponding author: Heon-Seock Cynn, Applied Kinesiology and
Ergonomic Technology Laboratory, Department of Physical Therapy, The Graduate
School, Yonsei University, Baekwoon-kwan, Yonsei
University, 1 Yonseidae-gil, Wonju, Kangwon-do, Korea. Tel.: +82 33 760 2427;
Fax: +82 33 760 2496; E-mail: [email protected]
Abstract: BACKGROUND: Patients with lower back pain due to lumbar
rotation with flexion syndrome (LRFS) have greater asymmetry of rotation in the
lumbopelvic region than healthy people. OBJECTIVE: To understand the
activities of the trunk muscle and kinematics of the trunk and pelvis in
patients with LRFS during the bird-dog (BD) exercise with dominant non-dominant
leg lifts, a frequently prescribed stabilization exercise. METHODS: We compared activity and kinematics during the BD exercise with dominant and
non-dominant leg lifts in 11 patients (6 male, 5 female) with LRFS who were
recruited from a university. RESULTS: Significantly lower activation of
the ipsilateral erector spinae muscle was found during the nondominant leg lift
than the dominant leg lift in patients performing the BD exercise (t =−3.71,
p=0.04). In addition, the trunk was significantly flexed during the
dominant leg lift (t=−6.069, p=0.00) and bent to the right side
(t=3.131, p=0.01) during both dominant and nondominant leg lifts. CONCLUSIONS: These results imply the presence of asymmetrical muscle activity
and kinematics in the trunks of subjects with LRFS. This information should be
considered for prescribing exercises to such subjects.
