Background: In patients with lumbar spinal stenosis (LSS), lumbar flexion exercise (LFE) is considered a standard therapeutic exercise that widens the space between the spinal canal and intervertebral foramen. However, some researchers have reported that lumbar extension exercise (LEE) may improve lumbar pain and functional ability in patients with LSS. Although exercise intervention methods for patients with LSS have been widely applied in clinical settings, few studies have conducted comparative analysis of these exercise methods.
Objects: This study aimed to compare the effects of LFE, LEE, and lumbar flexion combined with lumbar flexion-extension exercise (LFEE) on pain, range of motion (ROM), pelvic tilt angle, and functional gait ability in patients with LSS.
Methods: A total of 30 patients with LSS, LFE (n1=10), LEE (n2=10), and LFEE (n3=10) were assigned to each of the three exercise groups. The numerical pain rating scale (NPRS), modified-modified schober test (MMST)-flexion, MMST-extension, pelvic tilt inclinometer, and 6-minute walking test (6MWT) were measured.
Results: After the intervention, statistically significant differences were observed in the NPRS (p=.043), MMST-flexion (p<.001), MMST-extension (p<.001), and 6MWT (p=.005) between groups. According to the post hoc test, the NPRS was statistically significant difference between the LFEE and LEE groups (p=.034). The MMST-flexion was statistically significantly different between the LFE and LEE (p=.000), LFE and LFEE (p=.001), and LEE and LFEE (p=.001) groups. The MMST-extension was statistically significantly different between the LFE and LEE (p<.001), LFE and LFEE (p=.002), and LEE and LFEE (p=.008) groups. The 6MWT was statistically significantly different between the LFE and LFEE (p=.042) and the LEE and LFEE (p=.004) groups.
Conclusion: This study suggested that LFEE was the most effective exercise for pain and functional gait ability in patients with LSS, LFE was the most effective exercise for lumbar flexion ROM, and LEE was the most effective exercise for lumbar extension ROM.

Abstract
Introduction
Methods
    Instruments and measurement Sustained lumbar extension provocation test
    Modified lumbar extension test
    Numerical pain rating scale
    Modified modified schober test-flexion
    Modified modified schober testextension
    Pelvic tilt angle test
    6-minute walking test
    Intervention
    Lumbar flexion exercise
    Lumbar extension exercise
    Lumbar flexion combined extension exercise
    Statistical analysis
Results
    General characteristics of study subjects
    Comparisons of LFE, LEE, LFEE on NPRS, MMST flexion, MMST extension, PTA, 6MWT
    Post-Hoc comparisons of LFE, LEE, LFEE on changes value of NPRS, MMST flexion, MMST extension, 6MWT
Discussion
Conclusion
References

• Hyun-ho Do(Dept. of Rehabilitation Medicine, Konyang University Hospital)
• Seung-chul Chon(Dept. of Physical Therapy, College of Medical Science, Konyang University) Corresponding author