ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study design.Anin vivosheep model was used to investigate the effect of spinal instrumentation on the healing process of posterolateral spinal fusion.Objectives.To examine the role of spinal instrumentation during the healing process of posterolateral fusion.Summary of Background Data.In long bone fractures, internal fixation improves the union rate but does not accelerate the healing process. Spinal instrumentation also improves the fusion rate in spinal arthrodesis. However, it remains unclear whether the use of spinal instrumentation expedites the healing process of spinal fusion.Methods.Sixteen sheep underwent posterolateral spinal arthrodeses at L2–L3 and L4–L5 using equal amounts of autologous bone. One of those segments was selected randomly to be augmented with transpedicular screw fixation (Texas Scottish Rite Hospital spinal system). The animals were killed at 8 weeks or 16 weeks after surgery. Fusion status was evaluated by biomechanical testing, manual palpation, plain radiography, computed tomography, and histology.Results.Instrumented fusion segments demonstrated significantly higher stiffness than did uninstrumented fusions at 8 weeks after surgery. Radiographic assessment and manual palpation showed that the use of spinal instrumentation improved the fusion rate at 8 weeks (47%versus38% in radiographs, 86%versus57% in manual palpation). Histologically, the instrumented fusions consisted of more woven bone than the uninstrumented fusions at 8 weeks after surgery. The 16-week-old fusion mass was diagnosed biomechanically, radiographically, and histologically as solid, regardless of pedicle screw augmentation.Conclusion.The current study’s results demonstrated that spinal instrumentation creates a stable mechanical environment to enhance the early bone healing of spinal fusion.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.Serial changes in the rate of proteoglycan synthesis in rabbit discs after chemonucleolytic treatment with chymopapain and chondroitinase ABC were measured using anin vitromethod.Objectives.To determine the retained ability of the intervertebral disc to synthesize proteoglycans after chemonucleolytic treatment.Summary of Background Data.Most previous studies describe radiologic and histologic changes that occur after chemonucleolytic treatment. However, in humans it is not clear whether reconstitution of the disc space with normal nucleus proteoglycans can occur with time.Methods.Twenty-five rabbits were treated with chymopapain (10 units/0.1 mL/disc) and chondroitinase ABC (5 units/0.1 mL/disc) by intradisc injection. Five rabbits were killed at each interval, 1, 2, 4, 8 and 12 weeks after injection. Radiologic changes in the disc height were noted, and the rate of proteoglycan synthesis was determined biochemically.Results.After injection, no significant recovery of disc height was seen in either enzyme group after the initial disc narrowing. The average rate of proteoglycan synthesis in control rabbit intervertebral discs, those which had not been surgically treated, was 27.1 (× 10-6mmols sulphate/hour/dry weight). Twelve weeks after injection, the values were 21.6 in the saline group, 8.9 in the chondroitinase ABC group, and 8.2 in the chymopapain group.Conclusions.Doses within the therapeutic range can damage disc cells, at least in the rabbit, so that proteoglycan synthesis declined to 30% of control rates, and no significant recovery of disc height was observed.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.After autotransplanting the nucleus pulposus into the epidural space of rabbits, chondroitinase ABC was administered, and the effect of chondroitinase ABC was examined.Objectives.To examine whether chondroitinase ABC accelerates resolution of the nucleus pulposus transplanted into the epidural space.Summary of Background Data.No previous reports exist on the effect of chondroitinase ABC on the nucleus pulposus in the epidural space.Methods.In Study 1, autotransplantation of the nucleus pulposus into the epidural space was performed in rabbits. Histologic change was observed. In Study 2, dry weight, deoxyribonucleic acid content, and the amount of glycosaminoglycans of autotransplanted nucleus pulposus were quantified and compared with the respective values in the control group, chondroitinase-ABC–injected group, and phosphate-buffered saline–injected group. In Study 3, granulocytes obtained from the blood of a rabbit treated with chondroitinase ABC or phosphate-buffered saline were added to the nucleus pulposus taken from the same rabbit.Results.In chondroitinase ABC group, inflammatory cells tended to infiltrate earlier than those in the control group (Study 1). The dry weight of recollected nucleus pulposus in the chondroitinase ABC group was significantly less than in the other groups. Deoxyribonucleic acid content in the nucleus pulposus tended to be larger in the chondroitinase ABC group, although no significant difference in content compared with that in the other groups was found. Regarding the residual glycosaminoglycans in the transplanted nucleus pulposus, the amount of chondroitin sulfate markedly decreased in the chondroitinase ABC group (Study 2). The number of granulocytes infiltrating the nucleus pulposus was distinctly large in the chondroitinase ABC group (Study 3).Conclusion.Chondroitinase ABC can enhance resolution of the nucleus pulposus in the epidural space.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.A bending analysis of pedicle screws inserted into vertebral body analogues. Intravertebral and intrapedicular pedicle screw bending moments were studied as a function of sagittal insertion angle.Objectives.To determine how the pedicle screw bending moment is affected by changes in the insertion angle.Summary of Background Data.There is a significant incidence of failure when pedicle screws are used to instrument unstable spinal segments. Extrinsic factors that affect screw bending failure have been poorly characterized. Previous work has demonstrated that intrapedicular pedicle screw bending moments are significantly affected by the sagittal location and depth of pedicle screw placement.Methods.Pedicle screw transducers were inserted in analogue vertebrae at one of three orientations: 7° cephalad (toward the superior endplate), 7° caudal (toward the inferior endplate), or parallel to the superior endplate (control). An axial load was applied to the superior endplate of the vertebra, and screw bending moments were recorded directly from the transducers.Results.Screws angled 7° cephalad developed significantly greater mean intrapedicular bending moments compared with screws inserted caudal or control screws. There was no significant difference in bending moments realized within the vertebral body for the three screw positions.Conclusions.Angulating pedicle screws toward the superior endplate increased bending moments within the pedicle. If attention to optimal screw insertion technique can reduce bending moments and potential for screw failure without increasing morbidity, surgical risk, or operative time, then proper insertion technique takes on new importance.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.A study of inter- and intra-examiner reliability and clinical validity using two instruments for assessment of spinal range of motion in healthy individuals.Objective.To assess the clinical validity, stability, and normative values for active and passive cervical range of motion as measured by the CA-6000 (Orthopedic Systems Inc., Union City, CA), an electrogoniometer.Summary of Background Data.The authors’ early trials with the electrogoniometer yielded values that differed substantially from those in other reports. The authors sought to resolve those discrepancies and understand their sources.Methods.Axial rotations along the transverse, coronal, and frontal planes were measured as half-cycles (i.e.,left–right or flexion–extension) that were repeated seven times per trial. Test–retest data were collected on the same healthy individuals for active and passive motion using men and women aged 20–39 years. For validity, simultaneous digital dual inclinometry and electrogoniometry were performed twice over a 1-week interval. In addition, a bench test was performed for validation of axial rotation.Results.Clinical reliability of the CA-6000 was high for inter- and intra-examiner studies of total active motion, and validity was high when compared with that obtained with dual inclinometry. Total range of motion had less between-trial variability than half-cycles, axial rotation and lateral bending measurements had greater reliability than did flexion–extension measurements, and active motion was more reliable than passive motion.Conclusion.The CA-6000 provides valid and reliable measures of cervical range of motion. Discrepancies reported elsewhere appear to have arisen from several sources, as discussed in this article.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.A retrospective cohort study of adolescent idiopathic scoliosis. A comparison group of persons without scoliosis was also selected randomly from the general population.Objectives.To estimate the association between level of cigarette smoking and the prevalence and severity of back pain.Methods.A postal questionnaire was used to elicit information on smoking histories, a variety of indices of low back pain, and potential confounding factors. The association between smoking and back pain was estimated separately for men and women in the cohort and in the comparison group using ordinal regression models.Results.The questionnaire was completed by 1287 women and 184 men who had adolescent idiopathic scoliosis and by 1130 women and 621 men in the comparison population who did not have scoliosis. Statistically significant associations between back pain and current cigarette smoking were found in the two groups of women and men with scoliosis, but not among men selected from the general population. In the three former groups, proportional odds ratios comparing current smokers to persons who never smoked ranged from 1.4 to 1.9. Among current smokers, the prevalence of back pain increased with cigarette consumption, and the proportional odds ratios ranged from 1.2 to 1.8 per 10 pack-years (no. of cigarettes smoked per day × no. of years/20). In these three groups, intensity, frequency, and duration of episodes of back pain also were found to increase with smoking consumption.Conclusion.The finding that smokers have more frequent episodes of back pain may imply that smoking exacerbates back pain, and the observation that stronger associations between back pain and smoking were found in the scoliosis cohort suggests that smoking may have a greater impact onpersons with damaged spines.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.Cross-cultural adaptation and cross-sectional psychometric testing.Objectives.To develop and validate a cross-cultural version of the Roland-Morris Questionnaire for use in German-speaking patients with low back pain.Summary of the Background Data.Clinical research related to the management of back pain would be facilitated enormously if a small number of patient-oriented questionnaires became widely used. If the transposition of a questionnaire from its original cultural context is done by simple translation, it is unlikely to be successful because of language and cultural differences. Therefore, a simple direct translation of a questionnaire from one language to another does not permit its use in clinical trials.Methods.The instrument was translated and back-translated, pretested, and reviewed by a committee. The German version of the Roland-Morris Questionnaire was tested in 125 patients with low back pain. The study was conducted at the spa resort at Senftenberg, Austria, which is visited by patients from all countries of German-speaking Europe. Reliability and concurrent construct validity were assessed with Pearson’s correlation coefficient on the Roland-Morris Questionnaire scores compared with the scales of the Medical Outcome Study Short Form-36 questionnaire.Results.Pearson’s correlation coefficient for test–retest reliability of the German version was r = 0.82 (P= 0.0001), and Cronbach’s alpha was 0.81. The concurrent validity was r = 0.81 (Roland-Morris Questionnaire/pain rating;P= 0.0001), r = 0.48 (Roland-Morris Questionnaire/forward bending;P= 0.0001), and r = −0.47 (Roland-Morris Questionnaire/lateral bending;P= 0.0001). Correlation between the functional scales of the Medical Outcome Study Short Form-36 questionnaire and the Roland-Morris Questionnaire sum scores ranged from r = −0.29 (emotional limitations;P= 0.0011) to r = −0.71 (physical limitations;P= 0.0001).Conclusion.Because the German version of the Roland-Morris Questionnaire seems to be reliable and valid for the assessment of the functional status in German-speaking patients with low back pain, the use of this translated instrument can be recommended in future clinical trials.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.Postal questionnaire to individuals with back pain.Objective.To assess the acceptability, validity, and reliability of two existing back pain outcome measures, the Roland-Morris Questionnaire and the Von Korff scales, modified to measure the preceding 4 weeks.Summary of Background Data.The ideal outcome measure for studies of low back pain and disability remains elusive. Most existing measures assess current pain and disability. Measuring these factors over a preceding 4-week period may be more appropriate.Methods.Individuals with back pain identified in a community survey were asked to complete the modified questionnaires. Validity was assessed by comparison with the Medical Outcome Study Short Form 36 and two general comparator questions on self-reported pain and disability. Repeatability was assessed using retest questionnaires.Results.Completed questionnaires were returned by 95 individuals with chronic back pain. The modified Roland-Morris Questionnaire and Von Korff pain and Von Korff disability scales were completed satisfactorily by 83 (87%), 89 (94%), and 87 (92%) participants, respectively. Mean scores of the modified measures changed significantly and in a predictable manner with increasing ratings of pain and disability. They also correlated with aspects of the Medical Outcome Study Short Form 36 questionnaire. Retest data suggest that these measures are repeatable. The modified Roland-Morris Questionnaire provided adequate analyzable data only if missing values were imputed, and it explained less of the variance in the comparator questions than the modified Von Korff scales.Conclusions.The modified Von Korff scales were completed easily and appear to be valid and repeatable in this format.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Study Design.A systematic review of randomized controlled trials.Objectives.To evaluate the efficacy and effectiveness of acupuncture for the management of nonspecific low back pain.Summary of Background Data.Acupuncture is one of the oldest forms of therapy, but little is known about the effectiveness of acupuncture for low back pain.Methods.Randomized controlled trials were done to assess the effectiveness of all types of acupuncture treatment, which involves needling for subjects with nonspecific low back pain. Two reviewers blinded with respect to authors, institution, and journal independently assessed the methodologic quality of the studies. Because data were statistically and clinically too heterogeneous, a qualitative review was performed. The evidence was classified into four levels: strong, moderate, limited, or no evidence.Results.Eleven randomized controlled trials were included. Overall, the methodologic quality was low. Only two studies met the preset “high quality” level for this review. No study clearly evaluated acupuncture for acute low back pain. The results indicate that there was no evidence showing acupuncture to be more effective than no treatment. There was moderate evidence indicating that acupuncture is not more effective than trigger-point injection or transcutaneous electrical nerve stimulation, and there was limited evidence that acupuncture is not more effective than placebo or sham acupuncture for the management of chronic low back pain.Conclusions.Because this systematic review did not clearly indicate that acupuncture is effective in the management of back pain, the authors would not recommend acupuncture as a regular treatment for patients with low back pain. There clearly is a need for more high-quality randomized controlled trials.

ISSN:0362-2436    

出版商:OVID    

年代:1999

数据来源: OVID