Paraspinal Muscles Wasting in the Patients wih Chronic Low Back Pain

ABSTRACT

The purpose of this study is to investigate whether paraspinal muscle wasting occurs in association with chronic low back pain(LBP) and to know whether low back muscle exercise is effective for abating chronic low back pain. Cross sectional areas(CSA) of lumbar vertebral bodies and paraspinal muscles were measured using CT at the level of the fouth lumbar vertebral body in 37 patients(23 males 14 females) with acute low back pain and in 44 patients(20 males, 24 females) with chronic low back pin. The results were as follows; 1) The mean age of the patients with chronic LBP were higher than those with acute LBP. 2) The CSAs of L4 vertebral bodies were correlated significantly with body weight and the CSAs of L4 vertebral bodies, erector spinae and psoas muscles were larger in males than in females. 3) The volumes of the paraspinal muscles were significantly reduced in patients with chronic LBP compared to a cute LBP. These changes can cause erector spinae and psoas muscle weakness and disuse atrophy and thereby predispose to spinal instability and progressive dysfuction.