The effects of pain and strength on size of lumbar muscles in L-HNP microdiscectomy

The purpose of this study was to investigate the correlation between the pain and the muscle strength by confirming the size of cross-sectional of multifidus, erector spinae, and psoas in sixty six patients(40 males, 26 females) who were done microdiscectomy, the place where L-HNP were the most occurred frequently at L4-5, L5-S1. The pain was measured by the Numeric Pain Rating Scale, indicated by number and the muscle strength were used with the Centaur 3D Spatial Rotation Device(BFMC, Germany) with dual eight directions, indicated the highest activation at 0°, -45°, 45° for erector spinae and mutifidus. The cross-sectional of muscles were measured by MRI and PACS(picture archiving and communication system) with free handling technique was used to measure the cross-sectional area of multifidus, erector spinae, and psoas at L4,5 inferior disc. In order to evaluate the correlation between the pain and the cross-sectional area of spinal muscles before surgery and 5 days after surgery, and the correlation between the muscle strength and the cross-sectional of the spinal muscles, Spearman’s correlation coefficients were used each male and female. The significance level was p.05. results: The results before surgery showed that the multifidus has low correlation in correlations of multifidus size and pain. But there was no correlation in the size of cross sectional muscle and pain. Conclusion: The multifidus and psoas showed moderate correlation in correlation of muscle strength. Therefore, this study suggested that strengthening the deep muscles and spinals muscles were needed as spinal exercises before.