Comparison of lumbar muscle morphology in patients with chronic nonspecific low back pain with and without clinical lumbar segmental instability.

OBJECTIVES: Evaluation of spinal muscle morphology may be critical because of its impact on segmental stability and control of the lumbar spine in the subset of patients with clinical lumbar segmental instability (LSI). The purpose of this study was to compare lumbar muscle morphology in CNLBP patients with clinical LSI, CNLBP patients without clinical LSI. METHODS: This case-control study included 30 patients with CNLBP (15 with clinical LSI and 15 without clinical LSI) and 15 subjects without LBP. Axial magnetic resonance images from the L2 to S1 lumbar levels were used to evaluate the morphology of the lumbar muscles. RESULTS: A significant increase in the muscle-to-fat infiltration index and a significant decrease in the relative muscle cross-sectional area (rmCSA) of the multifidus muscle at the L3-L4 to L5-S1 levels were observed in both CNLBP groups compared to the control group (p<0.05). The mean erector spinae mean rmCSA was significantly greater in the clinical LSI group compared to the control group (SMD = 0.853, 95% CI = 0.105 to -1.6, P = 0.044) and also compared to the CNLBP without clinical LSI (SMD = 0.894, 95% CI = -1.645 to -0.144, P = 0.030) at the L4-L5 level. CONCLUSIONS: The atrophic changes of the multifidus muscle, in CNLBP patients with or without clinical LSI was observed. However, hypertrophic changes of the erector spinae muscle at the L4-L5 lumbar level were observed only in the clinical LSI group. Psaos major did not show significant atrophic or hypertrophic changes.

Radiographic Investigation of Lumbar Vertebrae in Patients with Flexion and Extension Movement Disorder Syndrome.

Objectives: The kinesiopathology model is a new rehabilitation model classifying, evaluating, and treating patients with non-specific back pain. Sahrmann proposed this model based on movement disorder syndromes. The present cross-sectional study aimed to evaluate the radiograph of the linear and angular displacement of the lumbar spine in patients with lumbar flexion impairment syndrome (LFIS) and lumbar extension impairment syndrome (LEIS). Methods: In this study, 50 adults aged 18-46 years were enrolled, including 25 patients with LFIS and 25 with LEIS. The eligible participants were referred to the radiology department for radiography in the common position of neutral, full extension, and full flexion position while standing. The White and Panjabi's method was used to measure the linear and angular displacements. Moreover, pain intensity was assessed using the visual analogue scale, and functional disability was investigated using a modified Oswestry Disability Questionnaire. Results: The parameter of the linear displacement at the L3-L4 level was significantly different between the two groups (P=0.02). The mean duration of low back pain was longer in the LEIS, compared to the LFIS group (P=0.01). Conclusion: In patients with LEIS, compensatory responses occur that cause less linear displacement at the L3-L4 level, compared to the patients with LFIS. Therefore, it is important to design appropriate exercises to better control the linear displacement at the L3-L4 level during the full range of motion in patients with LFIS.

Effects of micro-amperage direct current stimulation on injury potential and its relation to wound surface area in guinea pig.

INTRODUCTION: it is believed that the exogenous electrical stimulation via improving the natural endogenous bioelectric current, accelerate the wound healing. Up to now, this hypotheses has not been researched in acute surgically wounds. MATERIALS AND METHODS: Thirty-nine male guinea pigs were randomly divided into one control and two experimental groups (DC anodal group and DC cathodal group). A full thickness skin incision, length of 2.5 cm, was made on the dorsum of each animal The differential surface skin potential was measured before and immediately after the injury and also through the healing process until 21st days. RESULTS: Only in anodal group, there was not significant difference between the basal initial potential and the wound potential on days of 17, 19 and 21 (p>0.05). On days of 19 and 21, the wound potential decreased higher in anodal group than in control group (p<0.05). Wound surface area in two experimental groups decreased higher in 3rd weeks with respect to control group (p<0.05). DISCUSSION AND CONCLUSION: Anodal micro-amperage direct current can accelerate bioelectric events of skin wound and return more rapidly the wound potential to its before injury natural level.