Strengthening lumbar extensors--therapy of chronic back pain--an overview and meta-analysis

AIM: Low back pain ranks high among the reasons for physician office visits and is costly in terms of medical treatment. A number of studies have shown that low back pain patients have significantly lower trunk strength when compared with healthy controls. The working hypothesis at the beginning of the 1990's was that low back pain patients could be treated effectively using lumbar extension exercise. METHOD: 21 papers and abstracts reporting on lumbar extension training are rated. Validation was performed for each paper according to the internationally accepted system of the American Association of Spine Surgery in types A-E. RESULTS: 1100 cases from 21 publications and abstracts dealing with lumbar extension training were evaluated. We did not find a single type A study in our search. The clinical outcome of the studies was a reduction of pain, improvement of range of motion, improvement of spinal condition and of the lumbar extension strength. CONCLUSION: Prospective, randomized, controlled studies with long-term results should help to delineate further the role of isolated lumbar extension exercise for the treatment of low back pain and to test the efficacy compared to other methods of care.     

The association of low back pain, neuromuscular imbalance, and trunk extension strength in athletes

BACKGROUND CONTEXT: Imbalanced patterns of erector spinae activity and reduced trunk extension strength have been observed among patients with low back pain (LBP). The association between LBP and neuromuscular imbalance still remains unclear. PURPOSE: To examine the relationship between LBP, neuromuscular imbalance, clinical symptoms, and trunk extension strength on two independent occasions, after dynamic neuromuscular changes through a back exercise program. STUDY DESIGN/SETTING: Experimental longitudinal study of the lower back in a clinical setting. PATIENT SAMPLE: Eighty-two elite amateur tennis players with and without LBP. OUTCOME MEASURES: Clinical testing of spinal mobility and muscular flexibility of the lower back. Isometric voluntary maximum trunk extension strength. Surface electromyography (EMG) of lumbar erector spinae. METHODS: Athletes underwent a standardized clinical examination with common tests for spinal mobility and muscular flexibility, followed by an isometric trunk extension tests in a specially built apparatus with simultaneous surface EMG recording from right and left lumbar erector spinae. Imbalance quotients were calculated using integrated EMG (IEMG) measures. The relationships between LBP, neuromuscular imbalance, trunk extension strength, and clinical findings were investigated before and after a back exercise program using univariate and multivariate logistic regression models. RESULTS: A significant association between neuromuscular imbalance of erector spinae and the occurrence of LBP was observed, whereas no significant imbalances were found in subjects without LBP. The number of subjects with LBP decreased proportionally with the occurrence of neuromuscular imbalance in the lumbar region after the completion of a back exercise program. However, neuromuscular imbalances were still present during retesting among subjects whose LBP did not resolve; the relationship between neuromuscular imbalance of lumbar erector spinae and LBP was significant again. On the contrary, no significant association between LBP and maximum isometric trunk extension strength or neuromuscular imbalance and maximum isometric trunk extension strength was found before or after the exercise program. No clear relationship between LBP and clinical testing of the lumbar spine or neuromuscular imbalance and clinical testing was found on the two independent testing occasions. CONCLUSION: A direct relationship between LBP and neuromuscular imbalance was documented in athletes with LBP. Maximum isometric trunk extension strength had no relationship to the presence of LBP or the occurrence of neuromuscular imbalance of erector spinae. Common clinical testing of spinal mobility and muscular flexibility had only limited correlation to LBP and neuromuscular imbalance.     

Epidemiology of low back pain in the elderly: correlation with lumbar lordosis

We carried out an epidemiologic study to determine the prevalence of low back pain in elderly Japanese and to examine the correlation with lumbar lordosis in sagittal plane radiographs. Low back pain is an enormous clinical and public health problem. With the increasing use of spinal instrumentation, the measurement of lumbar lordosis is thought to be important. However, in elderly Japanese, the prevalence of low back pain and its correlation with lumbar lordosis is not clear. Five hundred and nine people, aged 50–85 years, were examined, and 489 subjects met our criteria. Clinical findings, physical status, and the visual analogue scale (VAS) of pain were examined in these subjects. Measurements and determination of total lordosis from L1-S1 were made from standing radiographs. Forty-eight percent of the subjects had experienced low back pain within the previous 3 months. Women had low back pain more frequently (P = 0.006). There was a significant difference in lumbar lordosis between the groups with and without low back pain (P = 0.0006). Lumbar lordosis was approximately 4° less in the low back pain group and there was no relationship to age or sex in either group. VAS was significantly inversely correlated with lumbar lordosis (P = 0.025, at rest). The body mass index (BMI) of the low back pain group was higher in women, but the difference was not significant (P = 0.06). In conclusion, lumbar lordosis was defined and its prevalence in elderly Japanese was reported together with VAS and physical data used to compare the two groups. Received: September 6, 2000 / Accepted: February 11, 2001     

Spinal mobility and trunk muscle strength in 15-year-old schoolchildren with and without low-back pain.

From a population of 1,503 schoolchildren, 38 15-year-old children suffering from low-back pain and 38 asymptomatic controls were selected for testing of spinal mobility and trunk muscle strength. The asymptomatic controls were matched by age, sex, and school class. In the group with recurrent or continual low-back pain (17 boys and 21 girls), the boys were over 4 cm taller than those in the control group. In both sexes sagittal mobility was decreased in lumbar extension and straight leg raising, and increased in lumbar flexion. Endurance strength in the abdominal and back muscles was decreased compared to the control pupils, who reported no back pain at all in the questionnaire collected 1 year before the testing procedure. The pupils reporting sciatica (n = 7) at some time, in addition to recurrent low-back pain, had decreased lumbar flexion and side bending compared to those with recurrent low-back pain (n = 31) without sciatica. The results of the study indicated that in this growing-age population there was a subgroup with recurrent low-back pain having a different spinal mobility pattern as well as decreased trunk muscle strength.     

Personal risk factors for first-time low back pain

STUDY DESIGN: A prospective study of personal risk factors for first-time low back pain. OBJECTIVES: To construct and validate a multivariate model to predict low back pain. SUMMARY OF BACKGROUND DATA: Various physical and psychological factors have been reported to increase the risk of low back pain, but conflicting results may be attributable to inaccurate "clinical" measures and to poorly validated statistical models. METHODS: A total of 403 health care workers aged 18-40 years volunteered for the study. None had any history of "serious" back pain requiring medical attention or time off work. The volunteers completed the following questionnaires: the modified somatic perception questionnaire, the Zung depression scale, and the Health Locus of Control. Anthropometric factors were quantified using standard techniques. The 3Space Isotrak device (Polhemus, VT) was used to measure lumbar curvature and hip and lumbar spine mobility. Leg and back strength and back muscle fatiguability were measured in functional postures. Postal follow-up questionnaires, sent after 6, 12, 18, 24, 30, and 36 months, inquired about back pain, and multivariate logistic regression was used to identify risk factors at each follow-up. RESULTS: The response rate fell from 99% at 12 months to 90% at 36 months, at which time 90 volunteers reported "serious" back pain and 266 reported "any" back pain. The following were consistent predictors of serious back pain: reduced range of lumbar lateral bending, a long back, reduced lumbar lordosis, increased psychological distress, and previous nonserious low back pain. Only the latter three were consistent predictors of "any" back pain. Physical factors had the most influence in a sub-population of volunteers who were new to the job. CONCLUSIONS: Personal risk factors explained up to 12% of first-time low back pain.     

Access to pedestrian roads, daily activities, and physical performance of adolescents

STUDY DESIGN: A cross-sectional study using a questionnaire and physical tests was performed. OBJECTIVE: To study how access to pedestrian roads and daily activities are related to low back strength, low back mobility, and hip mobility in adolescents. SUMMARY OF BACKGROUND DATA: Although many authorities express concern about the passive lifestyle of adolescents, little is known about associations between daily activities and physical performance. METHODS: This study compared 38 youths in a community lacking access to pedestrian roads with 50 youths in nearby area providing excellent access to pedestrian roads. A standardized questionnaire was used to obtain data about pedestrian roads, school journeys, and activities from the local authorities and the pupils. Low back strength was tested as static endurance strength, low back mobility by modified Schober techniques, and hip mobility by goniometer. For statistical analyses, a P value of 0.05 or less determined significance. RESULTS: In the area using school buses, the pupils had less low back extension, less hamstring flexibility, and less hip abduction, flexion, and extension than pupils in the area with pedestrian roads. Multivariate analyses showed no associations between walking or bicycling to school and anatomic function, but regular walking or bicycling to leisure-time activities associated positively with low back strength, low back extension, hip flexion, and extension. Distance by school bus associated negatively with hip abduction, hip flexion, hip extension, and hamstring flexibility (P<0.001). Time spent on television or computer associated negatively but insignificantly with low back strength, hamstring flexibility, hip abduction, and flexion (P<0.1). CONCLUSION: The results indicate that access to pedestrian roads and other lifestyle factors are associated with physical performance.     

Decreased joint and spinal mobility associated with low back pain in young adults

Anthropometric factors, spinal and limb-joint mobility, and trunk strength were measured in young students--55 men and 48 women (mean age 21.4 years, SD 1.6). Twenty-six of the men and 29 of the women had had back pain during the preceding year and they were compared with those without back pain. In the male back-pain group, extension, lateral flexion and the sum of mobility in the lumbar spine, and hip flexion and external rotation of the shoulders were significantly smaller. In the female back-pain group, extension and the sum of mobility in the thoracic spine, and extension, external rotation, and the sum of mobility in the hips were significantly diminished. Anthropometric factors and trunk strength had no significant relationship with a history of back pain except for a pronounced lordosis in women. The results suggest that ligamentous or capsular stiffness of the joints may be associated with low back pain in young adults.     

Predictors of isokinetic back muscle strength in patients with low back pain

STUDY DESIGN: Testing for trunk muscle strength was performed on 105 patients with chronic low back pain. OBJECTIVES: To investigate prediction of isokinetic back muscle strength in patients with low back pain. SUMMARY OF BACKGROUND DATA: The clinical evaluation of patients with chronic low back pain often in difficult because of discrepancy between disability and impairment. The isokinetic trunk device was developed as a tool for objective assessment of back muscle strength. However, the performance of patients depends on radiologic abnormalities of the spine, conditions of the back muscles, and various psychosocial factors. Studies are warranted that address how these variables influence back muscle strength. METHODS: The patients with chronic low back pain were tested by an isokinetic trunk muscle strength test (Cybex TEF, Ronkonkoma, NY). In addition, the following variables were recorded: gender, age, body mass index, emotional distress, pain on exertion, self-efficacy for pain, degenerative changes of the lumbar spine, cross-sectional area, and density of the erector spinae muscles. The three latter variables were estimated by computed tomography scans. The sum of the total work performed during isokinetic extension strength test was the dependent variable in a multiple regression analysis, and anthropometric, demographic, psychological, and radiologic factors were independent variables. RESULTS: Gender, cross-sectional muscle area, and pain on exertion were the most powerful predictors of isokinetic back muscle strength. The final regression model, which included these variables, could account for approximately 40% of the variability in back muscle strength. CONCLUSION: For assessing the results of an isokinetic trunk muscle strength test, cross-sectional muscle area, gender, and pain on exertion should be taken into account.     

Segmental lumbar mobility in individuals with low back pain: in vivo assessment during manual and self-imposed motion using dynamic MRI

Background

Altered spinal mobility is thought to be related to current or past episodes of low back pain; however evidence of that relationship in younger subjects has not been established. The purpose of this study was to compare lumbar segmental mobility in asymptomatic and symptomatic subjects during posterior to anterior (PA) manual spinal mobilization and a self-initiated prone press-up (PU) maneuver. We hypothesized that persons with central low back pain would have an altered lumbar segmental mobility pattern compared to those without pain.

Method

Forty-five individuals (age 32.1 ± 8.5) with non-specific low back pain and 20 persons (age 31.1 ± 7.0) without low back pain participated. Each subject underwent dynamic imaging of the lumbar spine during a PA mobilization procedure and while performing a PU. Segmental motion was quantified as the change in the intervertebral angle between the resting and end-range vertebral positions.

Results

The symptomatic group had a larger percentage of subjects with evidence of single level segmental hypermobility than the asymptomatic group during the PA (40.0% vs. 5%) and PU (26.7% vs. 15%) procedures. Single lumbar motion-segment analysis revealed hyper-mobility in symptomatic subjects at L5 – S1 (Chi-square = 10.0, p ≤ 0.01) and L4 – L5 (Chi-square = 4.18, p ≤ 0.05) during the PA test.

Conclusion

Persons with non-specific low back pain have a tendency to demonstrate single level lumbar segmental hypermobility when compared to age specific asymptomatic subjects.     

Active therapy for chronic low back pain part 1. Effects on back muscle activation, fatigability, and strength

DESIGN: Randomized prospective study of the effects of three types of active therapy on back muscle function in chronic low back pain patients. OBJECTIVES: To quantify the effects of 3 months active therapy on strength, endurance, activation, and fatigability of the back entensor muscles. SUMMARY OF BACKGROUND DATA: Many studies have documented an association between chronic low back pain and diminished muscular performance capacity. Few studies have quantified the changes in these measures following interventions using objective measurement techniques or related them to changes in clinical outcome. METHODS: A total of 148 individuals (57% women) with chronic low back pain (age, 45.0 +/- 10.0 years; duration of low back pain, 10.9 +/- 9.5 years) were randomized to a treatment that they attended for 3 months: active physiotherapy, muscle reconditioning on devices, or low-impact aerobics. Before and after therapy, assessments were made of the following: trunk muscle strength (in flexion, extension, lateral bending, and axial rotation), erector spinae activation (maximal, and during forward bending movements), back extensor endurance (Biering-S?rensen test), and erector spinae fatigability (determined from changes in the median frequency of the surface electromyographic signal) during isometric and dynamic tests. RESULTS: A total of 132 of 148 patients (89%) completed the therapy. Isometric strength in each movement direction increased in all groups post-therapy (P < 0.0008), most notably in the devices group. Activation of the erector spinae during the extension tests also increased significantly in all groups and showed a weak, but significant, relationship with increased maximal strength (P = 0.01). Pretherapy 55% of the subjects showed no relaxation of the back muscles at L5 when in the fully flexed position; no changes were observed in any group post-therapy. Endurance time during the Biering-S?rensen test increased significantly post-therapy in all groups (P = 0.0001), but there were no significant changes in EMG-determined fatigability. Fatigability of the lumbar muscles at L5 (EMG median frequency changes) during the dynamic test increased post-therapy (P = 0.0001) without group differences. CONCLUSION: Significant changes in muscle performance were observed in all three active therapy groups post-therapy, which appeared to be mainly due to changes in neural activation of the lumbar muscles and psychological changes concerning, for example, motivation or pain tolerance.     

Morphometry of the lower lumbar vertebrae in patients with and without low back pain

The authors made several measurements in the lower lumbar vertebrae of patients with and without low back pain. Our objective was to determine the allometric relationships between different dimensions of the lumbar canal, the effects on these from degenerative disease, and differences between the symptomatic and asymptomatic populations. We compared 119 patients suffering from low back and sciatic pain and 39 subjects without lumbar symptoms as determined by computed tomography (CT). The following measurements were made: sagittal diameter of the canal, interpedicular distance, interarticular distance, and anteroposterior diameter of lateral recess and foramen. With respect to the patients with lumbar pain, the asymptomatic group proved to have wider foramina from L3 to L5 and wider sagittal diameters in S1. The patients with canal stenosis revealed lower figures for all diameters of the central canal, lateral recess of L4, and foramina of L4 and L5. Patients with lumbarization showed smaller diameters of the central canal. CONCLUSION: There is an allometric relationship between the dimensions of the central canals. This relationship is less evident with lateral canals. The patients without lumbar symptoms had wider foramina and sagittal diameters in S1 than those with lumbar symptoms. Of these, patients who developed symptoms of canal stenosis demonstrated smaller diameters in central and lateral canals. Of the developmental anomalies, lumbarization proved to be associated with canal stenosis due to smaller diameters of the central canals.     

Influences of trunk muscles on lumbar lordosis and sacral angle

Background: The strength of abdominal muscle and back extensors or their balances are commonly mentioned as major indicators of potential low back pain (LBP). Former studies on anthropometrics in terms of trunk muscle strength seemed to lack precision in methodology. Furthermore, the extension-flexion ratio, which is a good parameter of trunk muscle balance, was not as much studied as simple maximum torques in this area of study. Objectives: To investigate relationship between trunk muscle strength and lumbar lordosis, sacral angle in patients who did not show significant abnormal findings on their simple lateral radiograph. Methods: Thirty-one subjects were participated and their mean age was 35. Lumbar simple lateral radiograph was taken and lordotic angle was obtained by altered Cobbs method. Sacral angle was also examined on the same film. The relationship between these angles and muscle strength (isometric maximum torques and ratios of them) was investigated by the correlation analysis. Results: None of the isometric maximum torques was related to sacral angle or lordotic angle. However, the ratio of extension to flexion was significantly related to the lordotic angle (Pearsons correlation coefficient=0.491, p<0.01). Other ratios were not related to any of the angles. Conclusions: An imbalance in trunk muscle strength can influence significantly lordotic curve of lumbar spine and might be one risk factor for potential low back pain.Supported by Reasearch Fund from KyungHee University     

腰椎间盘MRI局限性高信号对下腰痛诊断的临床意义

目的 分析腰椎间盘MRI局限性高信号区的影像学表现与临床对照,以提高对该征象的临床意义。方法 回顾分析35例下腰痛患者伴有腰椎间盘MRI局限性高信号区的影像学表现特征进行分析、诊断,对照临床资料及手术病理对照。结果 腰椎间盘MRI局限性高信号区MR矢状位T2WI图像呈圆形（71.4%）,弧形（20.0%）或放射状（8.6%）,病灶表现以圆形常见。轴位像为条状或梭形,与椎间盘纤维环破裂一致;高信号出现的位置与临床症状相符合。结论 腰椎间盘MRI局限性高信号区对诊断腰椎间盘性下腰痛有一定的特异性,出现该征象可提示椎间盘纤维环撕裂,为下腰痛患者的诊治提供参考。     

Differences in measurements of lumbar curvature related to gender and low back pain

STUDY DESIGN: Cross-sectional. OBJECTIVES: To test the assumption that postural alignment and gender have a bearing on the specific type of low back pain (LBP) a person manifests. BACKGROUND: Measurements of static sagittal lumbar curvature are used by clinicians in the management of patients with LBP, but no investigator has reported differences in curvature related to specific categories of LBP. METHODS AND MEASURES: We used a computer-interfaced, 3-D, electromechanical digitizer to derive curvature angles for the region of the spine between T12-L1 and S2. Trained clinicians examined the subjects and determined their LBP diagnoses. We used t tests to examine differences in curvature between women and men, those with and those without LBP, and those in 4 different categories of LBP. We used chi2 to examine the relationship between gender and LBP category. RESULTS: Lumbar curvature angle (lordosis) was 13.2 degrees larger for women than for men (t = 6.74; P<.01). There was no difference in lumbar curvature between people with undifferentiated LBP and people without LBP. There were differences in lumbar curvature between people in various categories of LBP, for example, subjects in the lumbar-rotation-with-extension category had 8.4 degrees more lumbar curvature than subjects in the lumbar-rotation-with-flexion category (t = 2.16; P<.05). Based on the frequency distributions, there was a significant relationship between gender and LBP category (chi2 = 10.19; P<.01). CONCLUSIONS: Measurements of lumbar curvature should be expected to differ between men and women and may be related to different types of low back pain.     

Lumbar spine kinesthesia in patients with low back pain.

STUDY DESIGN: Single-group, posttest only, using a sample of convenience. OBJECTIVE: To measure the repositioning error of subjects with low back pain for lumbar sagittal movement using a simple kinesthetic test previously described. BACKGROUND: Patients with low back pain are commonly observed to have difficulty in adopting a mid or neutral position of the lumbar spine. METHODS AND MEASUREMENTS: Twenty subjects with low back pain were required to reproduce an upright neutral posture of the lumbar spine following movement into flexion in a sitting position. Trunk positioning accuracy was measured with an electromagnetic tracking device. RESULTS: The mean absolute value of the repositioning error in the sagittal plane was 2.25 degrees +/-0.88 degrees on day 1 and 2.32 degrees +/-1.62 degrees on day 2. The performance of patients with low back pain was similar to that of asymptomatic patients in a previous study, although subjects with low back pain overshot the neutral position more frequently (79%) than did nonimpaired subjects (50%). CONCLUSIONS: Subjects with low back pain may have attempted to use extra mechanoreceptive cues to compensate for some kinesthetic deficit. Nevertheless, the kinesthetic test used was not sensitive enough to detect any repositioning deficits, and reasons for this are explored.     

Kinematic analysis of dynamic lumbar motion in patients with lumbar segmental instability using digital videofluoroscopy

The study design is a prospective, case–control. The aim of this study was to develop a reliable measurement technique for the assessment of lumbar spine kinematics using digital video fluoroscopy in a group of patients with low back pain (LBP) and a control group. Lumbar segmental instability (LSI) is one subgroup of nonspecific LBP the diagnosis of which has not been clarified. The diagnosis of LSI has traditionally relied on the use of lateral functional (flexion–extension) radiographs but use of this method has proven unsatisfactory. Fifteen patients with chronic low back pain suspected to have LSI and 15 matched healthy subjects were recruited. Pulsed digital videofluoroscopy was used to investigate kinematics of lumbar motion segments during flexion and extension movements in vivo. Intersegmental linear translation and angular displacement, and pathway of instantaneous center of rotation (PICR) were calculated for each lumbar motion segment. Movement pattern of lumbar spine between two groups and during the full sagittal plane range of motion were analyzed using ANOVA with repeated measures design. Intersegmental linear translation was significantly higher in patients during both flexion and extension movements at L5–S1 segment (p < 0.05). Arc length of PICR was significantly higher in patients for L1–L2 and L5–S1 motion segments during extension movement (p < 0.05). This study determined some kinematic differences between two groups during the full range of lumbar spine. Devices, such as digital videofluoroscopy can assist in identifying better criteria for diagnosis of LSI in otherwise nonspecific low back pain patients in hope of providing more specific treatment.     

Serial lumbar dynamometry in low back pain.

To determine the significance of changes in motor performance as measured by lumbar dynamometry, serial lumbar dynamometry was performed on a group of 45 male Workers' Compensation patients with chronic "mechanical" low back pain and in a group of 20 healthy male volunteers. The patients were men aged 20-60 years, whose current episode of low back pain had lasted for at least 3 months (mean 19.5 weeks, range 12-47 weeks). Testing was performed at entry into a "back school" program of therapy and again 2 weeks and 4 weeks later. The control group showed a slight improvement in almost all variables of strength and range of motion between the first and second tests but no significant change between the second and third tests. This was consistent with a learning effect. The patient group was analyzed as a whole and also in two groups based on their response to the Waddell maneuvers at entry: Waddell score 0-2 (no excessive illness behavior) and 3-5 (excessive illness behavior). As a whole, the patients showed significant progressive improvement in most variables on successive tests. The group with the low Waddell score had significantly greater strength and range of motion than the group with the high Waddell score but the trend of improvement with time was similar in the two groups. The authors conclude that in this sample of patients with low back pain, serial lumbar dynamometry reveals a progressive improvement in performance, which is greater than the improvement expected from the natural history of physical recovery and greater than the improvement expected from an increase in strength and range of motion attributable to the therapeutic exercises performed and is much larger than any learning effect related to the test procedure.     

Radiographic predictors of residual low back pain after laminectomy for lumbar spinal canal stenosis: minimum 5-year follow-up

STUDY DESIGN: Retrospective study of patients who underwent laminectomy for unification. OBJECTIVE: To identify radiographic predictors of residual low back pain (LBP) after laminectomy for lumbar spinal canal stenosis (LCS). SUMMARY OF BACKGROUND DATA: Residual LBP is a common complication of laminectomy and no radiographic predictors of its occurrence have been identified previously. METHODS: Clinical results and radiographic findings in 49 patients (21 males and 28 females, minimum 5-year follow-up) who underwent single level laminectomy for LCS were retrospectively reviewed. Patients who had an improvement in LBP scores in the Japanese Orthopedic Association (JOA) scoring system during the follow-up periods were classified as the recovery group, whereas those without improvements were classified as the nonrecovery group. Patients' clinical data (sex, duration of symptoms, age at surgery, JOA scores) and radiographic parameters (including lumbar lordotic angle, lumbar range of motion (ROM) and the intervertebral rotational angle) were analyzed to detect the factors significantly related with the occurrence of residual LBP. RESULTS: The average preoperative JOA score of 14.8+/-5.1 points improved to 21.6+/-5.5 points at the final follow-up providing an average recovery rate of 48.1+/-36.8%. Thirty-four and 15 patients were classified into the recovery and the nonrecovery groups, respectively. Binary logistic regression analysis revealed that significant predictors of residual LBP were preoperative lumbar lordosis angle and lumbar ROM. The mean preoperative lumbar lordosis and ROM in the nonrecovery group were significantly smaller than those in the recovery group (lordosis: 25.3+/-15.8 degrees vs. 37.8+/-13.6 degrees, P=0.006 and ROM: 22.1+/-10.6 degrees vs. 31.2+/-9.9 degrees, P=0.006). In addition, increase of the postoperative lumbar ROM was significantly larger in the nonrecovery than that in the recovery group (P=0.009). CONCLUSIONS: Our results indicate that preoperative lordosis angle and lumbar ROM were the significant radiographic predictors for residual LBP after laminectomy for LCS. Patient with flatback and limited lumbar mobility before surgery are prone to suffer residual LBP. It is suggested that these sagittal radiographic parameters should be taken into account when choosing laminectomy as the surgical option for LCS.     

The relationship between lumbar lordosis and radiologic variables and lumbar lordosis and clinical variables in elderly,African-American women

Several authors have hypothesized that there is a link between lumbar lordosis and low back pain. These relationships have not been previously described in a sample consisting exclusively of elderly, African-American women. The purpose of this study was to describe the relationship between lumbar lordosis and radiologic variables and lumbar lordosis and clinical variables in elderly, African-American women. A total of 475 African-American women enrolled in the multicenter Study of Osteoporotic Fractures participated in this ancillary, cross-sectional, study of lumbar lordosis. These women received lumbar spine radiographs and completed a questionnaire on low back pain and its impact on their daily lives. Lumbar lordosis tertiles were created based on radiographic measurements. Comparisons were made between the tertiles for differences in radiologic and clinical variables. Significant differences (p < 0.0025) were observed between the lordosis tertiles and the presence of spondylolisthesis, intervertebral disc space, and vertebral wedging. No significant differences were observed between the lordosis tertiles for the occurrence of low back pain, symptoms associated with low back pain, and disability experienced from low back pain. The degree of lumbar lordosis was associated with radiologic variables but was not associated with symptoms or decreased function from low back pain. These findings question the clinical utility of the lumbar lordosis measurement in elderly, African-American women.     

腰椎间盘MRI高信号区的组织病理学特点和临床意义

目的研究椎间盘源性下腰痛患者腰椎间盘纤维环后方MRI高信号区的组织病理学特征及其临床意义。方法对52例经保守治疗无效、CT片显示无腰椎间盘突出的下腰痛患者行腰椎MR检查及腰椎间盘造影术。男39例,女13例;平均年龄38.8岁。选择纤维环后方出现高信号区的部分病例行腰椎后路椎间盘切除、椎体间融合、椎弓根螺钉内固定术,术中收集包括高信号区部位的椎间盘。对标本行矢状面连续组织学切片,光镜下观察高信号区椎间盘组织的组织病理学结构,并分析其临床意义。结果在行腰椎间盘造影的52例142个椎间盘中,17例17个椎间盘显示高信号区,且在椎间盘造影过程中全部呈现2或3级的纤维环破裂和疼痛复制反应。敏感性和特异性均为100%。高信号区与纤维环破裂程度分级呈正相关,说明纤维环破裂程度分级越高,越易出现高信号区(R=0.462,P<0.01)。共收集11例患者11个椎间盘,组织学研究发现对应高信号区的椎间盘组织表现为沿纤维环裂隙形成的不同程度的血管化肉芽组织,有成熟的瘢痕化胶原组织。结论症状性下腰痛患者的腰椎MRI上有椎间盘高信号区,可以作为椎间盘源性下腰痛诊断的重要征象。