A critical review of reviews on the treatment of chronic low back pain

STUDY DESIGN: Systematic literature review. OBJECTIVE: To critically appraise the methodology of systematic reviews of conservative therapies for chronic nonspecific low back pain and to study the relation between the methodologic quality and other characteristics of these reviews. SUMMARY OF BACKGROUND DATA: Systematic reviews offer a concise summary of the evidence on treatment effectiveness, but flaws in their methodology can lead to invalid conclusions with serious implications for quality of patient care. METHODS: Searches of MEDLINE, EMBASE, Psychinfo, and the Cochrane Library were conducted. Titles, abstracts, and articles were reviewed by two blinded authors using three inclusion criteria: 1) chronic nonspecific low back pain, 2) systematic review, and 3) conservative treatment intervention. Data were extracted from each review by three authors. RESULTS: The search strategy retrieved 1102 titles and abstracts; 109 met inclusion criteria. A review of the full text of these articles excluded an additional 73 articles. Data abstraction and methodologic assessment were conducted on 36 articles reviewing 19 discrete interventions. The average quality score was 4.1, ranging from 1 (low) to 7 (high). There was a trend for recent reviews to be of higher quality. Fifty-six percent of the reviews had positive conclusions, but they had lower quality scores compared with those that had negative or uncertain conclusions. There were 27 (73%) qualitative and 10 (27%) quantitative summaries of results. CONCLUSIONS: Although the overall quality of systematic reviews was satisfactory, the quality of the individual papers included in the reviews varied considerably. The reviews often provided contradictory evidence on the effectiveness of a wide range of commonly used conservative interventions for chronic nonspecific low back pain. These findings illustrate the pitfalls of systematic reviews where there are a number of low-quality trials and underscore the need for high-quality primary trials that will allow for more conclusive reviews.     

Epidemiology of low back pain.

The science of epidemiology is difficult to apply to the problem of low back pain. This article discusses the problems associated with the study of low back pain, population surveys, risk factors for low back pain, and disability because of low back pain.     

Classification of nonspecific low back pain. I. Psychological involvement in low back pain. A clinical, descriptive approach.

An unselected sample of outpatient subjects (n = 330) with localized nonspecific low back pain (LBP) was studied. Investigation consisted of clinical assessment, physical examination, and psychiatric interview based on the DSM-III classification. A psychiatric disorder, according to the DSM-III criteria (axis I) was found in 41% of the subjects. Multiple correspondence analysis and cluster analysis were used to objectively identify clinical subtypes without preconceived theoretical models. Correspondence analyses suggested the existence of a 'psychological pain' syndrome consisting of several of the following symptoms: diffuse back pain, impossibility to assess intensity of pain on a pain scale, aggravation of pain by changing climate, by domestic activities or by psychological factors and dysesthesias in the back. Cluster analysis provided support for a four-group classification of low back pain, which may be interpreted through the relationships between psychological disturbances and the LBP clinical features. The results call for further investigation of the complex relationship between psychological disturbances and back pain. However, clinicians must be aware of the interest of a minimal psychiatric assessment in low back pain patients: psychiatric disorders frequently appear in these patients and an appropriate treatment of the psychiatric syndrome may reduce back pain.     

Pharmacologic treatment of low back pain.

This article provides basic pharmacologic and behavioral principles and facts to simplify drug therapy for low back pain. It outlines basic protocols for symptom control while definitive treatments are beginning or healing occurs.     

Myofascial aspects of low back pain.

Myofascial TrPs are an often overlooked but treatable source of pain and discomfort in the low back. They often complicate or coexist with other causes of low back pain, and they can mimic other neuromuscular or back musculoskeletal problems. Successful treatment of myofascial pain requires the identification of TrPs by manual examination, identification of mechanical or systemic perpetuating factors, treatment of the specific TrPs, and corrective action to prevent their recurrence.     

Nonsurgical care of low back pain.

Based on accumulating evidence, an important shift in the nonsurgical treatment paradigm for low back pain is underway. This shift is away from prolonged rest and passive therapy toward earlier patient activation and greater use of exercise therapy. The patient's best interest is often served by encouraging an early return to work and by avoiding adversarial legal proceedings. Patients should be reassured about the good prognosis of acute pain, and the alarming terminology of "injury" or "ruptured disc" should be avoided. Intervention to avoid sedentariness, smoking, and obesity probably offers important therapeutic and preventive opportunities. When surgery is indicated, the patient should have a major role in decision making after being provided an accurate view of risks and benefits of surgical intervention. Surgery should generally be reserved for those cases for which a benefit of surgery has been clearly established, avoiding the liberalization of indications to include imaging findings alone, persistent pain alone, or the failure of other treatments in the absence of clear surgical indications.     

Predicting disability from low back pain.

Since World War II, the incidence of chronic low back disability has increased dramatically, at a rate disproportionate to all other health conditions. The factors that contribute to this disability are reviewed. Psychosocial and work environmental factors are far more accurate predictors of disability than physical factors. A predictive risk model is described that allows an estimate of the patient's risk of becoming chronically disabled early in the course of a low back pain episode. This model demonstrates that work environment, perception of compensability, and the duration of the current episode are significantly predictors. Surprisingly, psychologic factors, as measured by the Minnesota Multiphasic Personality Inventory (MMPI), are not predictive in the cohorts studied to date. Although there are inherent limitations in study design, the results offer additional credence to the hypothesis that low back pain disability is often the result of psychosocial and work environmental factors. The model may also be used to address the hypothesis that patients at risk for future disability are more effectively treated by early, aggressive rehabilitation programs.     

椎间盘源性腰痛的分型

目的 介绍一种新的椎间盘源性腰痛的分型方法 ,以更好地指导临床诊断和治疗.方法通过回顾性分析386例慢性腰痛患者的椎间盘造影术中X线荧光影像和术后CT扫描片,结合术中患者有无一致性疼痛复制反应,将椎间盘源性腰痛进行分型.结果386例腰痛患者共行1056个椎间盘的腰椎间盘造影术,共有192例患者(49.7%)的226个椎间盘(21.4%)出现疼痛复制反应.192例出现疼痛复制反应的患者中,由于纤维环破裂(internal disc disruption,IDD)160例,由于终板破裂(internal end-plate disruption,IED)32例,分别占83.3%和16.7%.应用修正的Dallas CT椎间盘造影分级方法评估IDD患者纤维环放射状撕裂程度,应用术中荧光X线影像结合术后CT扫描评估IED患者终板放射状破裂程度.IDD患者纤维环破裂分级越高,椎间盘造影时一致性疼痛比例越大(r=-0.604,P=0.000).IED患者终板破裂程度越大,椎间盘造影时一致性疼痛比例越大(r=0.683,P=0.000).结论 根据临床研究结果,我们将椎间盘源性腰痛分为两种类型,由IDD引起的腰痛和由IED引起的腰痛.临床上这两种类型的椎间盘源性腰痛都要通过腰椎间盘造影术确诊,诊断过程、放射状撕裂方式和疼痛反应方式完全一致,表明其为一种科学、合理的分型方法.     

腰背痛流行病学进展

腰背痛患病率高,易复发,大多无明显病因,缺乏特异性表现,具有自愈倾向,仅少数腰背痛患者转为慢性。腰背痛的危险因素有年龄、心理、遗传、性别、职业、妊娠、体重、腰背痛病史、不良生活方式等。腰背痛患病率随年龄增长而增加,但到一定年龄阶段保持不变;社会心理因素对腰背痛的影响渐受重视;性别与腰背痛关系的报道不一;遗传可能是腰背痛最主要的危险因素;某些职业因素如负重、弯腰、旋转、振动等是腰背痛重要的危险因素;近年来与妊娠妇女相关的腰背痛受到重视;生活方式改变可使腰背痛患病率增加。X线和MRI等检查对腰背痛的诊断无特异性,仅适于排除腰背部特异性疾病。腰背痛的治疗方法很多,但流行病学调查显示缺乏有效方法,建议对不同病程采取相应治疗方法。目前腰背痛的预防未能降低发病率。     

Facet joint injection for low back pain. A clinical study

Therapeutic injection of facet joints is now widely practised, but British experience has been infrequently reported. We studied the results of injecting facet joints with a corticosteroid preparation in 50 patients suffering from the "facet syndrome". Our series included a number of extra-articular injections and these "failed injections" provide a useful control group. Results indicate that only intra-articular injections are effective; certainty of joint penetration can be ensured only by the routine use of joint arthrography.     

The lumbar disc and low back pain.

The lumbar disc serves to sustain compression loads and is subject to tension and shear in forward bending and rotation. Its outer third is innervated and can be a source of pain. The annulus fibrosus may be injured in rotation and flexion of the lumbar spine and may become symptomatic as a ligamentous injury. Compression injuries of the disc are initially asymptomatic but may set in train a degradative process that, in time, leads to internal disc disruption, which becomes symptomatic as a result of chemical or mechanical irritation of nociceptors in the annulus fibrosus. Disc prolapse is but one possible end stage of internal disc disruption and represents the culmination of a series of destructive processes affecting the disc. This condition can be symptomatic while the external appearance of the disc remains normal and before nerve roots are affected in any way.     

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.