CT measurement of trunk muscle areas in patients with chronic low back pain.

PURPOSE: The objective of this study was to determine the cross-sectional area changes of the paraspinal, isolated multifidus, quadratus lumborum, psoas, and the gluteus maximus muscles with CT in patients with chronic low back pain. MATERIALS AND METHODS: In this study, we evaluated 36 patients with chronic low back pain and 34 healthy volunteers. The mean age of the patients was 43.2 +/- 6.9 years (range, 30- 58 years) and the mean age of control group was 44.4 +/- 6.9 years (range, 31-61 years). We defined pain that lasts more then one year as chronic pain. Female patients were selected for standardization. All patients were housewives. None of the patients or controls engaged in physical activity other than routine housework. We used a visual analog scale and the Oswestry Pain Questionnaire for clinical evaluation. We made CT cross-sections of the paraspinal muscles at the upper and lower endplates of L4, and of the gluteus maximus at the head of the interfoveal level. RESULTS: In the patient group the multifidus, psoas, and quadratus lumborum cross-sectional areas were smaller than in the control group, and the P values were P = 0.002, P = 0.042, and P = 0.047, respectively, at the L4 endplate. At the L4 endplate level, cross-sectional areas of the multifidus and paravertebral muscles in the patient group were smaller than in the control group, and the difference was statistically significant (P = 0.001, P = 0.010, respectively). We did not find any significant difference between the patient and the control groups in gluteus maximus cross-sectional area. CONCLUSION: Chronic low back pain caused atrophy of the paraspinal, isolated multifidus, quadratus lumborum, psoas, and the gluteus maximus muscles to varying degrees, which was most prominent in the multifidus. Atrophy was noted in all of the studied muscles, except the gluteus maximus. The reliability of CT in measuring the cross-sectional areas of the back muscles was acceptable.

Loading is more effective than posture in lumbar spinal stenosis: a study with a treadmill equipment.

The objective of this study was to assess the correlation between neurogenic intermittent claudication (NIC) in LSS and different positions as well as loading status, using the treadmill device. The study was a prospective clinical trial on lumbar spinal stenosis (LSS) using a treadmill equipment. The study population comprised of 80 LSS patients with a mean age of 61. The equipment included a treadmill, unloading station and loading vests. The patients were instructed to walk in five different positions. The initiation time of symptoms and total walking time were recorded. The examination was stopped after 20 min or at the onset of severe symptoms. In order to obtain pretest demographic data on subjects, visual analog scale, Roland-Morris questionnaire, pain disability index, and Beck depression index were used. The initiation time of symptoms (ITS) and total walking time (TWT) were measured during the test. Unloading provided a longer and loading a shorter ITS and TWT. Decline or incline positions did not affect ITS or TWT. The changes in posture had no correlation with the appearance of symptoms in LSS patients with NIC on a treadmill in this study, rather ITS and TWT were determined by axial loading and unloading.

Measurement of spinal canal diameters in young subjects with lumbosacral transitional vertebra.

Despite the high prevalence of lumbosacral transitional vertebra (LSTV), little is known about the biomechanics of this condition. In addition, as previous studies have focused solely on symptomatic and elderly LSTV patients, the relationship between LSTV and congenital or developmental spinal stenosis remains uncertain. In the present study, the spinal canal diameters were measured in young subjects in whom degenerative changes have not yet become significant. Seventeen young adults with LSTV and 24 normal controls were included in this study. The spinal canal sagittal diameter, interpedicular distance, interfacet distance and lateral recess diameter were measured using CT scans. There was no significant difference in the measured values between the two groups. In conclusion, the results indicate that there is no relationship between LSTV and a congenitally narrower canal.