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Perceived pain and self-estimated activity limitations in women with back pain post-partum.

BACKGROUND AND PURPOSE: In the general population many daily activities have an impact on low back pain. The aim of the present study was to describe pain intensity, localization, type of sensation and perceived activity limitation in women with different back pain patterns post-partum. METHOD: In this cross-sectional survey 119 women with back pain persisting for two months after having given birth were interviewed and examined on average 7.2 months (range 6-10 months) post-partum. Based on pain provocation tests, four different back pain pattern groups were identified. Pain could be provoked in the area of the posterior pelvic/sacroiliac joints, in the lumbar spine, both in the posterior pelvic/sacroiliac joints and in the lumbar spine, and in none of the above areas. All women rated pain intensity on a visual analogue scale (VAS, 0-100 mm), and the pain localization and type of sensation were indicated on a pain drawing. They scored their activity limitations by use of the Disability Rating Index (DRI), which covers 12 daily activity items (VAS, 0-100 mm). RESULTS: There was no significant difference (p = 0.12) in pain intensity (range of medians 19.5-10 mm) between the four groups. However, on average, most areas in the lower back (median 5 mm (range 2-14 mm)), were marked in the group with pain in both the posterior pelvic/sacroiliac joints and in the lumbar spine. The women in the three groups where pain was provoked in the lower area of the back had significantly (p < 0.01) more difficulties with movement-related daily activities than the group where no pain could be provoked. CONCLUSIONS: The findings of this descriptive study suggest that back pain post-partum provoked by clinical tests considerably hampers movement-related activities. It seems important to pay special attention to the women where pain could be provoked in the lower back areas. The women should be identified early in the post-partum period to initiate adequate treatment.

Adult↗

[Clinical examination and electromyographic abnormalities in patients with lower back pain].

INTRODUCTION: Lower back pain (LBP) is one of the most frequent reasons for visits to basic and specialised health care centres and one of the commonest causes of referral for electromyographic (EMG) explorations. AIMS. The aim of this study is to determine the sensitivity and specificity of the clinical examination in patients with LBP and abnormal EMG findings. PATIENTS AND METHODS: A cross sectional study was carried out on 364 patients with LBP who had been referred to both basic and specialised clinics, and who were attended in the Electromyography Service of a hospital belonging to the Instituto de Seguros Sociales, throughout the years 2001 and 2002. The same clinical evaluation protocol (interview and physical examination) was applied to all the patients. They were also evaluated using the same electrophysiological protocol, which in all cases included a study of the H waves and the adductor longus, tensor fasciae latae, medial vastus, anterior tibial, extensor digitorum longus, the medial and lateral heads of gastrocnemius, gluteus maximus and paraspinal muscles. The abnormal EMG examination was taken as the reference criterion and we determined the sensitivity, specificity, probability ratio, pre test probability and post test probability of the following clinical categories: referred pain (RP), pain less than three months, muscular strength of dorsiflexors, plantarflexors and knee extensor mechanisms, hypaesthesia in the L4, L5, S1 dermatomes, patellar areflexia and Achilles areflexia. RESULTS: From the clinical history and physical examination, the pain referred to the extremity showed the highest sensitivity (80.89%), but its specificity was the lowest. This contrasted with the other clinical findings which, in general, showed high specificity (between 82.6% for hypaesthesia in the L5 dermatome and 97.5% for the weakness of the plantarflexors), but low sensitivity (from 6.37% for the weakness of the quadriceps to 35.67% for hypaesthesia in the L5 dermatome). Achilles areflexia showed the highest positive predictive value (85%) and the highest probability ratio (7.47), while the highest negative predictive value was found in pain referred to the extremity (68.75%). CONCLUSION: Although the clinical history and findings from the physical examination do not allow the prediction of a normal or abnormal electrophysiological result in patients with LBP, the interview and some of the clinical tests do make it easier to select which patients should be referred for an EMG exploration, the purpose of which is to aid the diagnosis of a lumbar radiculopathy.

Electromyography↗

Cross-sectional view of factors associated with back pain.

OBJECTIVE: To examine the factors associated with back pain within a working population. METHODS: A cross-sectional survey of employees using a self-administered questionnaire and physical fitness tests. This study assessed 10,321 participants (6,251 male and 4,070 female) of two nationwide companies throughout Switzerland between 1996 and 1998. The participation rate was 41%. RESULTS: Of the participants, 4,945 (48%) suffered mild back pain and 696 (7%) suffered severe back pain. Reported "stress" was associated with back pain of any intensity. Abdominal muscle strength was inversely associated with severe back pain, while physical activity was non-linearly associated with severe back pain. Smoking was directly associated with any intensity of back pain. The variables gender, obesity, strength of the abdominal musculature and frequency of physical activity were insignificant for back pain of any intensity in multivariate analyses. CONCLUSION: Our results confirm the association of back pain with physical and behavioural factors. The non-linear relationship between physical activity and back pain may need further examination. Performing any kind of sport three to four times a week appears optimal.

Abdominal Muscles↗

Surface EMG in chronic low back pain.

Chronic low back pain (CHLBP) occupies first place among factors restricting people's life activity under the age of 45. Frequency of CHLBP occurrence oscillates between 60 and 80%. Dysfunction of the erector trunci is a fundamental cause of CHLBP. The aim of the study was to evaluate the usefulness of surface electromyography (EMG) as an identification method in CHLBP. EMG apparatus was connected to a PC equipped with the EMG-LAB programme. This programme allows the registration, transformation, analysis and projection of results on-line. A summary of complete examination is presented in the form of statistical values of parameters such as mean amplitude, mean density, background amplitude, background density, and upper amplitude and upper density. Plain, surface electrodes were attached to the skin overlying the erector spinae at the T7 and L4 vertebrae, approximately 3-4 cm from the midline of the back. Electrodes were positioned unilaterally on the right side. A reference electrode was positioned on the skin overlying the right arm. Sixty-two patients with CHLBP were examined (30 men and 32 women, mean age 41 +/- 8 years). The control group consisted of 31 people without back problems (16 men and 15 women, mean age 39 +/- 6 years). The statistical values of mean amplitude, mean density and upper amplitude were found to be higher in the control group at the T7 level. At the L4 level, mean amplitude, mean density, background amplitude, background density and upper amplitude were significantly higher in control group. The findings of this study show that (1) dysfunction of the erector spinae plays a significant role in CHLBP, and (2) this process applies to small and large motor units, but the character of these changes is different in particular muscles. Surface EMG is an objective, non-invasive method of examining function of the erector spinae in the author's opinion.

Adult↗

Medical knowledge and the intractable patient: the case of chronic low back pain.

Chronic low back pain (CLBP) is endemic in Western societies, and while a good deal of attention has been paid to the lay experience of such pain, much less sociological attention has been paid to the way in which medical ideas about it have been formulated. This paper takes the latter course, tracing the development of clinical notions about the relationship between pathological signs and expressed symptoms from the 1820's to the 1930's, and then placing these developments in the context of postwar notions of 'somatization'. We point to the extent to which the disparity between expressed symptoms, pathological signs and perceived disability in CLBP has led to the moral character of the sufferer forming a constant subtext to medical discourse about the condition. We also note the extent to which medical ideas themselves have been constructed in intimate linkage with socio-legal questions of compensation and worker's insurance.

Attitude of Health Personnel↗

Assessment and correlation between clinical patterns, disability and health-related quality of life in patients with low back pain.

AIM: Low back pain (LBP) is the main symptom of most lumbar spine diseases. This symptom, due to physical, psychological and social factors, is correlated to a real disability which can affect the quality of life (QoL.) The aim of this study is to evaluate the QoL and the disability in patients with LBP and to correlate them to clinical patterns. METHODS: In this prospective multidimensional study, 108 patients underwent the following protocol: 1. collection of patient-oriented and disability data with the use of SF-36 and North American Spine Society (NASS); 2. collection of clinical, anamnestic and instrumental data (MRI, CT) with the use of DOVAC files; 3. assessment of disability with the use of Barthel index (BI) and deambulation index (DI). RESULTS: A significant correlation was found between the BI and the physical composite score (PCS), but no significant correlation was noticed between BI and the mental composite score (MCS). DI was not correlated to the SF-36. A positive Lasegue and the absence of the osteo-tendinous reflexes are significantly correlated to the disability and QoL. CONCLUSIONS: This study shows that there is no simple, linear correlation between QoL and disability.

Acute Disease↗

Do medical factors predict disability in older adults with persistent low back pain?

Persistent low back pain (LBP) is one of the most common and challenging persistent pain conditions in older adults. Medical comorbidity also is common in these individuals, but its impact on disability has not been examined. The purpose of this study was, using a cross-sectional design, to examine the functional impact of pain-related and general medical comorbidity on 100 community dwelling older adults (mean age 74.3) with persistent mechanical LBP. Subjects received a structured history and physical examination, lumbosacral spine X-rays, and standardized tests of physical function. Pain-related variables included intensity, duration, extent, and lumbar motion-induced pain. General medical variables included age, comorbidity, number of medications, depressive symptoms, back range of motion, body mass index, and severity of radiographic pathology. Function/disability measures included self-reported disability, gait speed, and mean number of static lifts and amount of work performed during a dynamic lifting task. Structural equation modeling was used to evaluate the influence of pain and medical variables on function/disability. The overall regression model indicated pain and medical variables were significantly associated with function/disability measures (R2=0.45, P<0.01). Individual regression coefficients, however, indicated that only pain duration (r=-0.36, P<0.05) and pain severity (r=0.37, P<0.001) were significantly associated with function/disability. Despite the prevalence of medical co-morbidities in older PLBP subjects, they appear to be of limited utility in understanding level of disability. These findings also underscore the need to optimize pain treatment in independent older adults to optimize physical function and delay the onset of dependent living status.

Aged↗

Adaptive changes in postural strategy selection in chronic low back pain.

Chronic low back pain (CLBP) patients achieve postural stability during challenging stance conditions by increasing sway speed. We investigated the mechanisms underlying this behavior, and whether postural strategy selection may be influenced by short-term experience of postural perturbation. Thirteen CLBP patients and thirteen age-matched controls underwent posturography tests. Subjects were asked to stand quietly: (a) with eyes open and eyes closed, and (b) while expecting a series of four backward translations of the support surface. Data from condition (a) was subjected to sway density analysis (SDA). This computes the number of consecutive spaces and respectively time samples during which center of pressure (COP) displacements remained inside a 2.5 mm radius. Three parameters of this analysis were considered: the mean number of peaks (MP), reflecting the time spent by COP in regions of stability, the mean time between peaks (MT) relating to the rate of production of posturographic commands, and the mean spatial distance (MD), reflecting the distance between stable regions. In condition (b) the mean COP positions were analyzed during the time (500 ms) preceding each translation. The MD was significantly increased in the CLBP group as compared to controls (P < 0.01), while the MP and MT did not present any significant difference. The expectation of backward translations initially produced a different COP positioning between the two groups (P < 0.0001) which decreased with repetition of platform translations (controls: PDelta1-4 < 0.002; patients: PDelta1-4 < 0.005). The findings show that the timing and the rate of the balance motor commands is comparable between the two groups. On the other hand, there is greater distance between regions of stability in the patient group. Such modification of motor control patterns might be the consequence of a reweighting of sensory input, possibly due to a deterioration of its reliability. Platform translation findings show that both groups aimed at optimizing their posture selection strategy based on prior testing experience. CLBP patients make use of a different postural motor strategy to maintain quiet stance. This is probably the consequence of an imprecise internal estimate of body sway, due to reduced accuracy in the sensory integration process.

Adaptation, Physiological↗

Spatially Contextualized Integrative Genomics Highlights Neuronal and Glial Regulatory Programs in Low Back Pain.

PURPOSE: Low back pain (LBP) is a heterogeneous pain condition with a measurable genetic contribution, but the genes, brain cell types, and spatial tissue contexts through which inherited risk is expressed remain unclear. We aimed to define cell-type-specific and spatially contextualized genetic mechanisms underlying LBP. METHODS: FinnGen R12 LBP GWAS summary statistics (42,521 cases and 353,224 controls) were integrated with brain single-nuclei eQTL data across eight major brain cell classes. We evaluated genome-wide polygenic signal using LDSC, prioritized genes using MAGMA and PoPS, and performed brain cell-type-specific eQTL-anchored Mendelian randomization, primarily based on single-instrument Wald ratio estimates, followed by Bayesian colocalization. Spatial genetic mapping was conducted using gsMap in an E16.5 murine embryonic atlas and two adult human lumbar spinal cord Visium sections. Selected candidates were assessed by RT-qPCR in neuronal-like and astroglial-like inflammatory cell models. RESULTS: LDSC supported interpretable polygenic signal for LBP. MAGMA and PoPS showed partial gene-level convergence, with TCF4 and TMEFF2 supported by both approaches. Across 1641 tested gene-cell type exposures, significant eQTL-anchored MR associations were concentrated in excitatory neurons, oligodendrocytes, inhibitory neurons, and astrocytes. Integrated eQTL-anchored MR, colocalization, and gene-prioritization evidence highlighted CLEC18A, QPRT, and GMPPB as higher-priority non-MHC candidates with moderate, but not strong, colocalization support. gsMap localized LBP-associated enrichment to neuroaxis-related embryonic regions, including brain, spinal cord, sympathetic nerve, and dorsal root ganglion, and to neuronal-like niches in adult lumbar spinal cord. RT-qPCR showed model-dependent expression changes, with QPRT and LGI4 preferentially responsive in neuronal-like SH-SY5Y cells and GMPPB and DPYSL5 responsive in astroglial-like U251 cells. CONCLUSION: These findings support neuronal and glial regulatory programs as plausible contributors to LBP genetic susceptibility and highlight CLEC18A, QPRT, and GMPPB as higher-priority non-MHC candidates with moderate colocalization support. The results provide a spatially contextualized framework for candidate prioritization in LBP, while emphasizing the need for larger cell-type-specific eQTL resources and functional validation before therapeutic or mechanistic conclusions can be drawn.

Mendelian randomization↗

Limited clinical utility of pain drawing in assessing patients with low back pain.

OBJECTIVE: The aim of this study was to assess the use of pain drawing by studying its ability to identify patients with low back pain and abnormal psychological profile. The intraevaluator repeatability of the penalty point method of scoring of pain drawing was also evaluated. METHODS: A total of 331 consecutive patients with low back pain were prospectively recruited. The psychologic profile was assessed using the Hospital Anxiety and Depression Scale. The pain drawings were scored with the penalty point method. The ability of pain drawing to identify patients with significant anxiety and depression was assessed by calculating the sensitivity, specificity, and positive predictive value. The intraevaluator repeatability was calculated for scoring done at an interval of 1 month using the kappa statistic. RESULTS: There were statistically significant differences in the anxiety and depression scores in patients with normal (n = 200) and abnormal (n = 131) pain drawing (anxiety: 9 +/- 4 vs 10.3 +/- 3.7; depression: 8.1 +/- 3.5 vs 8.8 +/- 3.6; P < 0.005). The pain drawing had a low sensitivity for detecting patients with any degree of anxiety (43%) or depression (40%). The positive predictive value of pain drawing for anxiety and depression was 78% and 69%, respectively. The kappa value for intraobserver assessment was 0.6 (P < 0.05). CONCLUSION: Though there are differences in anxiety and depression scores in patients with normal and abnormal pain drawing, the performance characteristics of pain drawing are less than acceptable and therefore limit its use in clinical practice.

Anxiety↗

Nonsteroidal anti-inflammatory drugs for low back pain: a systematic review within the framework of the Cochrane Collaboration Back Review Group.

STUDY DESIGN: A systematic review of randomized and double-blind controlled trials was performed. SUMMARY OF BACKGROUND DATA: Nonsteroidal anti-inflammatory drugs are the most frequently prescribed medications worldwide and are widely used for patients with low back pain. OBJECTIVES: To assess the effects of nonsteroidal anti-inflammatory drugs in the treatment of nonspecific low back pain with or without radiation, and to assess which type of nonsteroidal anti-inflammatory drug is most effective. METHODS: For this study, the Cochrane Controlled Trials Register, Medline and Embase, and reference lists of articles were searched. Two reviewers blinded with respect to authors, institution, and journal independently extracted data and assessed the methodologic quality of the studies. If data were considered clinically homogeneous, a meta-analysis was performed. If data were considered clinically heterogeneous, a qualitative analysis was performed using a rating system with four levels of evidence: strong, moderate, limited, and no evidence. RESULTS: This review involved 51 trials and 6057 patients. Of these trials, 16 (31%) were of high quality. The pooled relative risk for global improvement after 1 week was 1.24 (95% confidence interval [CI] = 1.10-1.41), and for additional analgesic use was 1.29 (95% CI = 1.05-1.57), indicating a statistically significant but small effect in favor of nonsteroidal anti-inflammatory drugs as compared with a placebo. The results of the qualitative analysis showed that there is conflicting evidence (Level 3) that nonsteroidal anti-inflammatory drugs are more effective than paracetamol for acute low back pain, and that there is moderate evidence (Level 2) that nonsteroidal anti-inflammatory drugs are not more effective than other drugs for acute low back pain. There is strong evidence (Level 1) that various types of nonsteroidal anti-inflammatory drugs are equally effective for acute low back pain. CONCLUSIONS: The evidence from the 51 trials included in this review suggests that nonsteroidal anti-inflammatory drugs are effective for short-term symptomatic relief in patients with acute low back pain. Furthermore, there does not seem to be a specific type of nonsteroidal anti-inflammatory drug that is clearly more effective than others. Sufficient evidence on chronic low back pain still is lacking.

Adolescent↗

Experts' opinions on complementary/alternative therapies for low back pain.

BACKGROUND: Complementary/alternative therapies are used for low back pain more frequently than for any other indication, yet evidence for or against their efficacy is fragmentary. Notwithstanding this void, the high prevalence of such therapies drives their integration into our health care systems. Expert opinions on the use of complementary/alternative therapies for low back pain could therefore be helpful until more data from randomized, controlled trials become available. OBJECTIVE: A postal questionnaire survey was designed to generate opinion from a systematically identified expert panel on the clinical effectiveness of complementary/alternative therapies for low back pain. METHODS: Computerized searches were conducted to systematically identify by objective criteria 50 clinical experts on low back pain. Each panel member received a questionnaire to assess the perceived clinical effectiveness of complementary/alternative therapies for 4 defined categories of low back pain. RESULTS: For acute uncomplicated low back pain, osteopathy and chiropractic were rated as effective by most experts. For chronic uncomplicated low back pain, most experts considered acupuncture as effective. Experts perceived homeopathy generally as ineffective for any type of low back pain. Clinical experience with herbalism as a treatment for low back pain was insufficient to form an opinion. CONCLUSION: Experts' opinion is in favor of the effectiveness of osteopathy and chiropractic for acute uncomplicated low back pain. Acupuncture is judged to be of some value for chronic, uncomplicated low back pain. Homeopathy is perceived as ineffective for any type of low back pain. Insufficient experience with herbalism as a treatment for low back pain prevents firm conclusions.

Acute Disease↗

Prevalence of back pain in pregnancy.

The prevalence of back pain was studied in 855 pregnant women who were followed from the 12th week of pregnancy, every 2nd week, until childbirth. The 9-month period prevalence was 49%, with a point prevalence of 22-28% from the 12th week until delivery. Because 22% of the women had back pain at the 12th week of the pregnancy, the 6-month incidence was 27%. Based on pain drawings, back pain was classified into three groups: In one group, pain was localized to the sacroiliac areas and increased as pregnancy progressed; in the other two groups, pain either decreased or did not change, respectively. True sciatica with a dermatomal distribution occurred in only 10 women (1%). Back problems before pregnancy increased the risk of back pain, as did young age, multiparity, and several physical and psychological work factors.

Adult↗

The effectiveness of acupuncture in the management of acute and chronic low back pain. A systematic review within the framework of the Cochrane Collaboration Back Review Group.

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.

Acupuncture Analgesia↗

Determinants of pain behaviour in patients with chronic low back pain.

Experience of pain is manifested by a subject's behaviour, i.e. by verbalization, movements, facial expressions etc. Experience of pain is a latent construct, and the question of whether the pain is "real" becomes secondary when the behavioural aspect is emphasised: "When the patient communicates pain, then there is a pain problem". The task of the clinician and the researcher is to find out what is behind a person's response to pain. The pain behaviour is determined by many factors. These include psychological suffering due to emotional distress; learning processes regulating pain behaviour; anticipated pain and fear of pain as a cause of passivity and avoidance behaviour in chronic low back pain patients; the influence of cognitive factors, particularly the relationship between negative expectations, cognitive distortion and activity; and finally, the role of psychological distress in chronic pain. These factors are discussed in this paper. Some empirical studies are briefly reviewed to illustrate the topic. Implication of these conceptualizations for treatment of and outcome research in chronic low back pain will be briefly discussed.

Back Pain↗

Low back pain in Paget's disease of bone.

Clinical and laboratory evaluation with bone scan, radiography, and computed tomography were performed on 25 patients with severe Paget's disease of bone and low back pain. Back pain was classified as caused by Paget's disease in only three patients. The remaining 22 patients had coexistent Paget's disease and osteoarthritis. There was difficulty separating the cause of back pain in those patients with coexistent Paget's disease and osteoarthritis, even when the diseases were present at different levels of the spine. The pathogenesis of Paget's disease appears to precipitate osteoarthritis and several low back syndromes. Suppressive therapy with disodium etidronate (EHDP) for Paget's disease was of benefit in eight of 22 patients (36%) with identifiable osteoarthritis. It is suggested that EHDP and perhaps other suppressive agents for Paget's disease receive limited use in patients with back pain unless a defined pagetic lesion appears related to the clinical syndrome in the absence of identifiable osteoarthritis.

Back Pain↗

Cyclobenzaprine and back pain: a meta-analysis.

BACKGROUND: Back pain is a common problem for which cyclobenzaprine hydrochloride is frequently prescribed. OBJECTIVE: To perform a systematic review of cyclobenzaprine's effectiveness in the treatment of back pain. METHODS: We searched MEDLINE, PsycLIT, CINAHL, EMBASE, AIDSLINE, HEALTHSTAR, CANCERLIT, the Cochrane Library, Micromedex, Federal Research in Progress, and the references of reviewed articles, and contacted Merck, Sharpe and Dohme for English-language, randomized, placebo-controlled trials of cyclobenzaprine in adults with back pain. Outcomes included global improvement and 5 specific domains of back pain (local pain, muscle spasm, range of motion, tenderness to palpation, and activities of daily living). Study quality was assessed using the methods of Jadad. Summary outcomes were obtained using a random-effects model. RESULTS: Patients treated with cyclobenzaprine were nearly 5 times (odds ratio, 4.7; 95% confidence interval, 2.7-8.1) as likely to report symptom improvement by day 14 as were those treated with placebo. Slightly fewer than 3 individuals (2.7; 95% confidence interval, 2.0-4.2) needed treatment for 1 to improve. The magnitude of this improvement was modest, with an effect size of 0.38 to 0.58 in all 5 outcomes (local pain, muscle spasm, tenderness to palpation, range of motion, and activities of daily living). Treatment efficacy for these 5 outcomes was greatest early, in the first few days of treatment, declining after the first week. Patients receiving cyclobenzaprine also experienced more adverse effects, the most common being drowsiness. CONCLUSIONS: Cyclobenzaprine is more effective than placebo in the management of back pain; the effect is modest and comes at the price of greater adverse effects. The effect is greatest in the first 4 days of treatment, suggesting that shorter courses may be better. Studies comparing the relative value of acetaminophen, nonsteroidal anti-inflammatory drugs, and cyclobenzaprine individually and in combination in the treatment of back pain are needed.

Amitriptyline↗