EMG has been extensively used to study function of back muscle, which plays an important role in the objective assessment of occupational low back pain, yet the inherent large variability of EMG signals across subjects produced by reasons already known or unknown may mask true biological differences. Some useful parameters abstracted from 8-channel EMG signal in time-frequency domain are used or proposed and calculated in this paper to decrease this variability, when comparing the possible difference between low back pain patients and normal control group. The calculation of instantaneous median frequency is improved to decrease the interruption of background noise, and different power densities in EMG time-frequency spectrogram are observed in two tested groups.
Back ; Electromyography ; Fourier Analysis ; Humans ; Low Back Pain ; physiopathology ; Muscle, Skeletal ; physiopathology ; Spectrum Analysis

OBJECTIVETo evaluate the reliability of flexion-extension ratio (FER) of lumbar erector muscle in surface EMG for the diagnosis of nonspecific chronic low back pain.

METHODSAccording to diagnostic study strategies, 73 patients with chronic low back pain and 86 controls were recruited in this study, FER of lumbar erector muscle were recorded in surface EMG for all the subjects. The critical value of FER for the diagnosis of nonspecific chronic low back pain was selected according to the receiver operator characteristic curve by SPSS. Sensitivity, specificity and accuracy were calculated and analyzed as well.

RESULTSThe FER in patients group was significantly higher than that in the control group. The critical value of FER was 0.68 with sensitivity, specificity and accuracy was 78.1%, 95.3% and 87.4% respectively.

CONCLUSIONFER of lumbar erector muscle might be practically applied as an objective indicator on the diagnosis of nonspecific chronic low back pain in surface EMG.

Chronic Disease ; Electromyography ; Humans ; Low Back Pain ; diagnosis ; physiopathology

OBJECTIVETo evaluate the role of muscle fatigue in the pathogenesis of high prevalence of low back pain(LBP) in drivers who work at high altitude, in order to seek the effective measures for prevention and treatment of LBP.

METHODThe spectral electromyographic(EMG) changes during isometric contraction of erector spinalis to fatigue in 26 drivers in the field were consecutively recorded after daily driving for 5 days. The relationship between the decline of median frequency and the development of the back extensor fatigue were analyzed.

RESULTSThe decline rates of EMG median frequency of the erector spinalis on 1-5 working day [(-0.258 +/- 0.087), (-0.248 +/- 0.070), (-0.256 +/- 0.097), (-0.267 +/- 0.093), (-0.274 +/- 0.081)%/s respectively] were significantly different from that of baseline measured before work [(-0.175 +/- 0.114)%/s, P < 0.05 or P < 0.01]. A positive correlation was also found between the decline rate and the working time(r = -0.809, P < 0.05).

CONCLUSIONThe high prevalence of LBP in the drivers working at high altitude is due to acumulative fatigue of back extensor resulting from long-distance driving, lack of proper rest, decrease of muscle endurance and increase of liability to fatigue, consequently leading to the muscle dysfunction and finally LBP.

Altitude ; Automobile Driving ; Electromyography ; Humans ; Low Back Pain ; etiology ; physiopathology ; Muscle Fatigue ; physiology ; Occupational Diseases ; etiology

Dynamic stabilization system plays an important role in the treatment of the degenerative lumbar spine. Fusion of short movement segments has little influences on the motion of lumbar spine. Meanwhile, preservation of movements of segment can prevent the degeneration of adjacent segment and maintain the possibility of disc replacement even under the condition that facet joints need to be excised. While maintaining the normal lumbar motion, dynamic stabilization system can not only decrease the load of intervertebral disc of corresponding movement segments and provide a good environment for the recovery of intervertebral disc and soft tissues, but also delay the degeneration of small facet and reconstruct the biomechanical function of spine.
Biomechanical Phenomena ; Humans ; Intervertebral Disc Displacement ; surgery ; Low Back Pain ; physiopathology ; surgery

Spinal "Gucuofeng" mainly is considered as abnormalities of joint function. Manipulative maneuver have obviously effect in adjustment of spinal "Gucuofeng", and the technical key point is utilization of principle of lever to achieve safe, effective and labor-saving purpose. After clinical practice, the general principle of manipulative maneuver in adjustment of spinal "Gucuofeng" can be summed up as pull stretch traction, first-induced instability, reverse adjustment,withdraw along situation.
Adaptation, Psychological ; Exercise Therapy ; Humans ; Low Back Pain ; surgery ; Manipulation, Spinal ; methods ; Social Adjustment ; Spine ; physiopathology

The purpose of this study is to show the correlation between the range of spinal motion and the severity of chronic lower back pain. The subjects of this study were 40 female patients with chronic lower back pain over a 6 months' duration. The range of spinal and hip joint motion was measured with a electrogoniometer, and the severity of back pain was evaluated with the Rolland's score and Pollard's pain disability index. Results were as follows. There was a correlation between the severity of pain and the range of lumbar lateral flexion, rotation, and extension (p< 0.05). Age, height, weight and body mass index had no correlation with the range of spinal motion. These results suggest that the range of lumbar spinal motion can be used as an objective measure for the evaluation of classifying chronic lower back pain patients and for planning and following their treatment.
Adult ; Back Pain/*physiopathology ; Chronic Disease ; Female ; Human ; Middle Age ; *Range of Motion, Articular ; Rotation ; Spine/*physiopathology ; Support, Non-U.S. Gov't

OBJECTIVETo find out the regular pattern of pain reaction by pressing along the Governor Vessel at the levels of T3 to L4 on the back in patients with digestive system disease, so as to provide references for diagnosis of the disease.

METHODSThirty patients diagnosed with digestive system disease by gastroscopy and colonoscopy as well as 16 patients with digestive symptoms without accurate diagnosis by endoscopy checks were observed. Pressing was applied from Zhiyang (GV 9) to Yaoyangguan (GV 3), including non-acupoints along the Governor Vessel. Positive reaction was recognized since pain, soreness or distension sensation appeared in the space between the spinous process.

RESULTSThe positive ratios of 30 patients with endoscopy checks and 16 without the check accounted for 100.0%. The tender spots, usually 5 to 9 in number, were mainly focused on the relative acupoints and non-acupoints along the Governor Vessel from T6 to T10.

CONCLUSIONThe pain reaction from Lingtai (GV 10) to Zhongshu (GV 7), which are at the level of T6 to T10, along the Governor Vessel is closely related with digestive system disease. And it can be regarded as function criterion of the digestive system and important reference of auxiliary diagnosis.

Acupuncture Points ; Adult ; Aged ; Back ; physiopathology ; Diagnosis, Differential ; Digestive System Diseases ; diagnosis ; physiopathology ; Female ; Humans ; Male ; Meridians ; Middle Aged ; Pain ; Pain Measurement ; Sensation

OBJECTIVETo observe the difference of the clinical effects of different needle retention times for acute lumbar sprain treated with float needle.

METHODSOne hundred and twenty patients with acute lumbar sprain were randomly divided into a 6 h group, a 12 h group, a 24 h group and a western medication group, 30 cases in each one. In the three float needle groups, plastic hose was detained near the pressure pain point on the lumbar after subcutaneous scattering with float needle. The needle retention time was 6 h, 12 h and 24 h respectively. In the western medication group, 75 mg voltaren tablet was adopted orally every day and the treatment was given for four days. Visual analogue scale (VAS) and Oswestry dysfunction index (ODI) about low back pain were observed before and after treatment. Also, the comprehensive effect was assessed after treatment.

RESULTSAfter treatment, the VAS scores and the ODI scores were improved obviously than those before treatment in all groups (all P< 0. 05). In the three float needle groups, the VAS scores and the ODI scores were superior to those in the western medication group (all P<0. 05). The differences in VAS scores and ODI scores among the three float needle groups were not statistically significant after treatment (all P>0. 05). The effective rate in the 6 h, 12 h and 24 h group was 93. 3% (28/30), 90. 0% (27/30) and 93. 3% (28/30) respectively, which were better than 73. 3% (22/30) in the western medication group (all P<0. 05).

CONCLUSIONThe effect of float needle for acute lumbar sprain is better than voltaren, and there is no apparent difference in retention times.

Acupuncture Therapy ; Adult ; Aged ; Female ; Humans ; Low Back Pain ; physiopathology ; therapy ; Lumbar Vertebrae ; injuries ; physiopathology ; Male ; Middle Aged ; Needles ; Sprains and Strains ; physiopathology ; therapy ; Young Adult

Animals ; Humans ; Intervertebral Disc Degeneration ; physiopathology ; Low Back Pain ; etiology ; pathology ; Lumbar Vertebrae ; blood supply ; Risk Factors ; Smoking ; adverse effects

OBJECTIVETo explore the morphometric abnormalities of brain gray matter (GM) in patients with chronic low back pain (CLBP).

METHODSThirty patients with CLBP and 30 healthy individuals were enrolled and examined with a 3.0 T magnetic resonance (MR) scanner. High-resolution T1 structural MR data were acquired and data analysis was performed using voxel-based morphometry (VBM) in FMRIB Software Library. The morphological differences were compared between the two groups.

RESULTSs Compared with the healthy control subjects, patients with CLBP showed decreased GM volumes in several brain cortical areas including the bilateral superior frontal gyrus, right frontal pole, left insular cortex, left middle and left inferior temporal gyrus (P<0.05, after TFCE correction). Increased GM volumes were found in the patients in the subcortical structures including the left thalamus, bilateral putamen, bilateral nucleus accumben and right caudate nucleus (P<0.05, after TFCE correction).

CONCLUSIONPatients with CLBP have different patterns of GM abnormalities in different brain regions, characterized by reduced GM volume in cerebral cortical regions and increased GM volume in the subcortical nuclei. Such changes might be associated with the maladaptation of the brain in chronic pain state.

Cerebral Cortex ; Frontal Lobe ; Gray Matter ; diagnostic imaging ; pathology ; Humans ; Low Back Pain ; physiopathology ; Magnetic Resonance Imaging ; Temporal Lobe ; Thalamus