Øystein P. Nygaard

Randomized clinical trial of lumbar instrumented fusion and cognitive intervention and exercises in patients with chronic low back pain and disc degeneration.

Study Design. Single blind randomized study. Objectives. To compare the effectiveness of lumbar instrumented fusion with cognitive intervention and exercises in patients with chronic low back pain and disc degeneration. Summary of Background Data. To the authors’ best knowledge, only one randomized study has evaluated the effectiveness of lumbar fusion. The Swedish Lumbar Spine Study reported that lumbar fusion was better than continuing physiotherapy and care by the family physician. Patients and Methods. Sixty-four patients aged 25–60 years with low back pain lasting longer than 1 year and evidence of disc degeneration at L4–L5 and/or L5–S1 at radiographic examination were randomized to either lumbar fusion with posterior transpedicular screws and postoperative physiotherapy, or cognitive intervention and exercises. The cognitive intervention consisted of a lecture to give the patient an understanding that ordinary physical activity would not harm the disc and a recommendation to use the back and bend it. This was reinforced by three daily physical exercise sessions for 3 weeks. The main outcome measure was the Oswestry Disability Index. Results. At the 1-year follow-up visit, 97% of the patients, including 6 patients who had either not attended treatment or changed groups, were examined. The Oswestry Disability Index was significantly reduced from 41 to 26 after surgery, compared with 42 to 30 after cognitive intervention and exercises. The mean difference between groups was 2.3 (−6.7 to 11.4) (P = 0.33). Improvements inback pain, use of analgesics, emotional distress, life satisfaction, and return to work were not different. Fear-avoidance beliefs and fingertip-floor distance were reduced more after nonoperative treatment, and lower limb pain was reduced more after surgery. The success rateaccording to an independent observer was 70% after surgery and 76% after cognitive intervention and exercises. The early complication rate in the surgical group was 18%. Conclusion. The main outcome measure showed equal improvement in patients with chronic low back pain and disc degeneration randomized to cognitive intervention and exercises, or lumbar fusion.

Lumbar instrumented fusion compared with cognitive intervention and exercises in patients with chronic back pain after previous surgery for disc herniation: a prospective randomized controlled study.

Abstract The effectiveness of lumbar fusion for chronic low back pain after surgery for disc herniation has not been evaluated in a randomized controlled trial. The aim of the present study was to compare the effectiveness of lumbar fusion with posterior transpedicular screws and cognitive intervention and exercises. Sixty patients aged 25–60 years with low back pain lasting longer than 1 year after previous surgery for disc herniation were randomly allocated to the two treatment groups. Experienced back surgeons performed transpedicular fusion. Cognitive intervention consisted of a lecture intended to give the patient an understanding that ordinary physical activity would not harm the disc and a recommendation to use the back and bend it. This was reinforced by three daily physical exercise sessions for 3 weeks. The primary outcome measure was the Oswestry Disability Index (ODI). Outcome data were analyzed on an intention‐to‐treat basis. Ninety‐seven percent of the patients, including seven of eight patients who had either not attended treatment (n = 5) or changed groups (n = 2), completed 1‐year follow‐up. ODI was significantly improved from 47 to 38 after fusion and from 45 to 32 after cognitive intervention and exercises. The mean difference between treatments after adjustment for gender was −7.3 (95% CI −17.3 to 2.7, p = 0.15). The success rate was 50% in the fusion group and 48% in the cognitive intervention/exercise group. For patients with chronic low back pain after previous surgery for disc herniation, lumbar fusion failed to show any benefit over cognitive intervention and exercises.

The Inflammatory Properties of Contained and Noncontained Lumbar Disc Herniation

Study Design. The inflammatory properties of nucleus pulposus were assessed in biopsy samples from patients who underwent surgery for lumbar disc herniation. Objectives. To investigate the inflammatory properties of the different types of disc herniation. Background Data. High levels of phospholipase A2 previously have been demonstrated in a small number of patients undergoing lumbar disc surgery. Phospholipase A2 is the enzyme responsible for the liberation of arachidonic acid from cell membranes at the site of inflammation and is considered to be the limiting agent in the production of prostaglandins and leukotrienes, which are powerful mediators of inflammation. Cytokines are among the many agonists inducing phospholipase A2 activation. Several reports previously have demonstrated the difference in clinical appearance of different types of lumbar disc herniation. Methods. Thirty‐seven patients undergoing surgery for lumbar disc herniation were investigated. During surgery the disc pathology of each patient was classified into one of three groups: bulging disc, contained herniation, and noncontained disc herniation. Also during surgery, biopsy samples were taken from the nucleus, immediately frozen in liquid nitrogen, and subsequently stored at −70 C until analyzed. Results. No traces of interleukin‐6 or tumor necrosis factor alpha were found in the biopsy samples. There was a significant difference in the levels of leukotriene B4 and thromboxane B2 in contained versus noncontained disc herniation, and the highest concentration was found in the noncontained disc herniation group. Conclusion. The results support the theory that inflammatory mechanisms are involved in sciatica because of lumbar disc herniation and indicate that the different types of disc herniation have different inflammatory properties.

The impact of body mass index on the prevalence of low back pain: the HUNT study.

Study Design. A cross-sectional population-based study. Objective. To examine the association between body mass index and chronic low back pain, with adjustment for potential confounders. Summary of Background Data. Although many studies have investigated this association, it is still unclear whether there is a general relationship between body mass index and low back pain which applies to all populations. Methods. This study is based on data collected in the HUNT 2 study in the county of Nord-Trøndelag in Norway between 1995 and 1997. Among a total of 92,936 persons eligible for participation, 30,102 men and 33,866 women gave information on body mass index and indicated whether they suffered from chronic low back pain (69% participation rate). A total of 6293 men (20.9%) and 8923 women (26.3%) experienced chronic low back pain. Relations were assessed by logistic regression of low back pain with respect to body mass index and other variables. Results. In both sexes, a high body mass index was significantly associated with an increased prevalence of low back pain. In men the estimated OR per 5 kg/m2 increase in body mass index was 1.07 (95% CI: 1.03–1.12) and in women 1.17 (95% CI: 1.14–1.21), after adjustment for age, with a significantly stronger association in women. Additional adjustment for education, smoking status, leisure time physical activity, employment status, and activity at work hardly affected these associations. No interactions were found with most other factors. Conclusion. This large population-based study indicates that obesity is associated with a high prevalence of low back pain. Further studies are needed to determine if the association is causal.

Effect of caudal epidural steroid or saline injection in chronic lumbar radiculopathy: multicentre, blinded, randomised controlled trial

Objective To assess the efficacy of caudal epidural steroid or saline injection in chronic lumbar radiculopathy in the short (6 weeks), intermediate (12 weeks), and long term (52 weeks). Design Multicentre, blinded, randomised controlled trial. Setting Outpatient multidisciplinary back clinics of five Norwegian hospitals. Participants Between October 2005 and February 2009, 461 patients assessed for inclusion (presenting with lumbar radiculopathy >12 weeks). 328 patients excluded for cauda equina syndrome, severe paresis, severe pain, previous spinal injection or surgery, deformity, pregnancy, ongoing breast feeding, warfarin therapy, ongoing treatment with non-steroidal anti-inflammatory drugs, body mass index >30, poorly controlled psychiatric conditions with possible secondary gain, and severe comorbidity. Interventions Subcutaneous sham injections of 2 mL 0.9% saline, caudal epidural injections of 30 mL 0.9% saline, and caudal epidural injections of 40 mg triamcinolone acetonide in 29 mL 0.9% saline. Participants received two injections with a two week interval. Main outcome measures Primary: Oswestry disability index scores. Secondary: European quality of life measure, visual analogue scale scores for low back pain and for leg pain. Results Power calculations required the inclusion of 41 patients per group. We did not allocate 17 of 133 eligible patients because their symptoms improved before randomisation. All groups improved after the interventions, but we found no statistical or clinical differences between the groups over time. For the sham group (n=40), estimated change in the Oswestry disability index from the adjusted baseline value was −4.7 (95% confidence intervals −0.6 to −8.8) at 6 weeks, −11.4 (−6.3 to −14.5) at 12 weeks, and −14.3 (−10.0 to −18.7) at 52 weeks. For the epidural saline intervention group (n=39) compared with the sham group, differences in primary outcome were −0.5 (−6.3 to 5.4) at 6 weeks, 1.4 (−4.5 to 7.2) at 12 weeks, and −1.9 (−8.0 to 4.3) at 52 weeks; for the epidural steroid group (n=37), corresponding differences were −2.9 (−8.7 to 3.0), 4.0 (−1.9 to 9.9), and 1.9 (−4.2 to 8.0). Analysis adjusted for duration of leg pain, back pain, and sick leave did not change this trend. Conclusions Caudal epidural steroid or saline injections are not recommended for chronic lumbar radiculopathy. Trial registration Current Controlled Trials ISRCTN No 12574253.

Surgery with disc prosthesis versus rehabilitation in patients with low back pain and degenerative disc: two year follow-up of randomised study

Objective To compare the efficacy of surgery with disc prosthesis versus non-surgical treatment for patients with chronic low back pain. Design A prospective randomised multicentre study. Setting Five university hospitals in Norway. Participants 173 patients with a history of low back pain for at least one year, Oswestry disability index of at least 30 points, and degenerative changes in one or two lower lumbar spine levels (86 patients randomised to surgery). Patients were treated from April 2004 to September 2007. Interventions Surgery with disc prosthesis or outpatient multidisciplinary rehabilitation for 12-15 days. Main outcome measures The primary outcome measure was the score on the Oswestry disability index after two years. Secondary outcome measures were low back pain, satisfaction with life (SF-36 and EuroQol EQ-5D), Hopkins symptom check list (HSCL-25), fear avoidance beliefs (FABQ), self efficacy beliefs for pain, work status, and patients’ satisfaction and drug use. A blinded independent observer evaluated scores on the back performance scale and Prolo scale at two year follow-up. Results The study was powered to detect a difference of 10 points on the Oswestry disability index between the groups at two years. At two years there was a mean difference of −8.4 points (95% confidence interval −13.2 to −3.6) in favour of surgery. In the analysis of prespecified secondary outcomes, there were significant differences in favour of surgery for low back pain (mean difference −12.2, −21.3 to −3.1), patients’ satisfaction (63% (n=46) v 39% (n=26)), SF-36 physical component score (mean difference 5.8, 2.5 to 9.1), self efficacy for pain (mean difference 1.0, 0.2 to 1.9), and the Prolo scale (mean difference 0.9, 0.1 to 1.6). There were no significant differences in return to work, SF-36 mental component score, EQ-5D, fear avoidance beliefs, Hopkins symptom check list, drug use, and the back performance scale. One serious complication of leg amputation occurred during surgical revision of a polyethylene dislodgement. The drop-out rate was 20% (34) and the crossover rate was 6% (5). Conclusions Surgical intervention with disc prosthesis for chronic low back pain resulted in a significantly greater improvement in the Oswestry score compared with rehabilitation, but this improvement did not clearly exceed the prespecified minimally important clinical difference between groups of 10 points, and the data are consistent with a wide range of differences between the groups, including values well below 10 points. The potential risks of surgery and the substantial amount of improvement experienced by a sizeable proportion of the rehabilitation group also have to be incorporated into overall decision making. Trial registration NCT 00394732.

Four-year follow-up of surgical versus non-surgical therapy for chronic low back pain.

Objectives To compare the long-term effectiveness of surgical and non-surgical treatment in patients with chronic low back pain. Methods Two merged randomised clinical trials compared instrumented transpedicular fusion with cognitive intervention and exercises in 124 patients with disc degeneration and at least 1 year of symptoms after or without previous surgery for disc herniation. The main outcome measure was the Oswestry disability index. Results At 4 years 14 (24%) patients randomly assigned to cognitive intervention and exercises had also undergone surgery. 15 (23%) patients assigned fusion had undergone re-surgery. The mean treatment effect for the primary outcome was 1.1; 95% CI −5.9 to 8.2, according to the intention-to-treat analysis and −1.6; 95% CI −8.9 to 5.6 in the as-treated analysis. There was no difference in return to work. Conclusions Long-term improvement was not better after instrumented transpedicular fusion compared with cognitive intervention and exercises.

Transforaminal steroid injections in the treatment of cervical radiculopathy. A prospective outcome study

SummaryBackground. The aim of this study was to assess if transforaminal steroid injections applied to cohort of patients waiting for cervical disc surgery, reduce the pain of cervical radiculopathy and hence reduce the need for surgical intervention.Cervical radiculopathy due to cervical disc herniation or spondylosis is a common indication for cervical disc surgery. Surgery is however not always successful, and is not done without risk of complications.Transforaminal injection of steroids has gained popularity due to the rationale that inflammation of the spinal nerve roots causes radicular pain, and therefore steroids placed locally should relieve symptoms.Methods. During a 12-month period, 21 secondary referral patients with unilateral cervical radiculopathy entered the study. Cervical disc herniation or spondylosis affecting the corresponding nerve root was demonstrated by appropriate investigation (MRI or myelography).The patients then received 2 transforaminal steroid injections, at 2 weeks interval, while waiting for operative treatment.The pain intensity (VAS), Odom’s criteria and operative indications were registered at 6 weeks and 4 months.Findings. After receiving injection treatment 5 of the 21 patients decided to cancel the operation due to clinical improvement. A statistically significant reduction (0.02) in radicular pain score was simultaneously measured. This corresponds well with the reduction in operative requirements since radicular pain is the main indication for operative treatment. The responders experienced a long-lasting effect.Those responding positively however improved neck pain to the same extent as radicular pain, and patients with cervical spondylosis responded as positively as those with disc herniation.Interpetation. This prospective cohort study indicates a reduction in the need for operative treatment due to injection treatment. The clinical effect is measurable, and a statistically significant improvement of the radicular pain is registered.Routine transforaminal injection treatment prior to surgery seems rewarding, but the complication risk must be taken into consideration.

The Function of Sensory Nerve Fibers in Lumbar Radiculopathy: Use of Quantitative Sensory Testing in the Exploration of Different Populations of Nerve Fibers and Dermatomes

Study Design. The function of sensory nerve fibers in patients with lumbar radiculopathy and in control individuals was evaluated using quantitative sensory testing. Objectives. To investigate the effect of lumbar nerve root compression on different populations of nerve fibers and to explore the function of sensory nerve fibers in neighboring nerve roots not involved in the mechanical compression. Background Data. Results from experimental and clinical studies indicate that chronic compression of lumbar nerve roots affects the large myelinated nerve fibers. The majority of nerve fibers involved in the sensation of pain, however, are small afferent nerve fibers. It is therefore of interest to study the effect of compression on large and small sensory afferent channels. Several authors have elucidated the biochemical interaction between disc tissue and nerve roots. Chemical substances in the epidural space can reach the nerve fibers in nerve roots at the same or neighboring lumbar segments. In this way, fibers not involved in the mechanical compression may be affected. Methods. The small nerve fibers were studied using tests for thermal thresholds (thermotest), and the large myelinated fibers were studied by vibrametry. Forty‐two patients were investigated in the symptomatic and the asymptomatic leg, and the results were compared with those of 21 healthy individuals. Results. The thresholds of cold, warmth, and vibration were significantly increased in the dermatome of the compressed nerve root, indicating that large and small sensory nerve fibers were affected. Further, the thresholds were significantly increased in the neighboring dermatomes in the symptomatic and the asymptomatic leg. Conclusion. Large and small sensory afferent nerve fibers are affected in lumbar radiculopathy. The increase in sensation thresholds in the ipsilateral neighboring dermatome and in the dermatomes in the asymptomatic leg indicates that adjacent nerve roots are involved in the pathophysiology of sciatica in patients with lumbar disc herniation.

Magnetic resonance imaging assessment of the alar ligaments in whiplash injuries: a case-control study.

Study Design. Case-control study. Objective. To use high-resolution magnetic resonance imaging (MRI) in assessing signal intensity areas in the alar ligaments. Summary of Background Data. Conflicting evidence exists whether areas of high signal intensity in the alar ligament on MRI are more frequent in whiplash patients than in noninjured control subjects. Methods. A case-control designed study of 173 subjects included one group with persistent whiplash associated disorder Grade I–II after a car accident (n = 59), one with chronic nontraumatic neck pain (n = 57) and one group without neck pain or previous neck trauma (n = 57). High-resolution proton-weighted MRI in 3 planes was used. The images were independently evaluated by two experienced neuroradiologists who were blinded to patient history and group allocation. The alar ligaments were evaluated according to a 4-point grading scale; 0 = low signal intensity throughout the entire cross section area, 1 = high signal intensity in one third or less, 2 = high signal intensity in one-third to two thirds, and 3 = high signal intensity in two thirds or more of the cross section area. Results. Alar ligament changes Grade 0 to 3 were seen in all 3 diagnostic groups. Areas of high signal intensity (Grade 2–3) were found in at least one alar ligament in 49% of the patients in the whiplash associated disorder Grade I–II group, in 33% of the chronic neck pain group and in 40% of the control group (&khgr;2, P = 0.22). Conclusion. The previously reported assumption that these changes are due to a trauma itself is not supported by this study. The diagnostic value and the clinical relevance of magnetic resonance detectable areas of high intensity in the alar ligaments are questionable.