Tom Bendix

Magnetic resonance imaging and low back pain in adults: a diagnostic imaging study of 40-year-old men and women.

Study Design. Cross-sectional cohort study of a general population. Objective. To investigate “abnormal” lumbar spine magnetic resonance imaging (MRI) findings, and their prevalence and associations with low back pain (LBP). Summary of Background Data. The clinical relevance of various “abnormal” findings in the lumbar spine is unclear. Distinguishing between inevitable age-related findings and degenerative findings with deleterious consequences is a challenge. Methods. Lumbar spine MRI was obtained in 412, 40-year-old individuals. Predefined “abnormal” MRI findings were interpreted without any knowledge of patient symptoms. Associations between MRI abnormalities and LBP were calculated using odds ratios. The “overall picture” of each MRI finding was established on the basis of the frequencies, diagnostic values, and the strength and consistency of associations. Results. Most “abnormal” MRI findings were found at the lowest lumbar levels. Irregular nucleus shape and reduced disc height were common (>50% of individuals). Relatively common (25% to 50%) were hypointense disc signal, anular tears, high intensity zones, disc protrusions, endplate changes, zygapophyseal joint degeneration, asymmetry, and foraminal stenosis. Nerve root compromise, Modic changes, central spinal stenosis, and anterolisthesis/retrolisthesis were rare (<25%). Most strongly associated with LBP were Modic changes and anterolisthesis (odds ratios >4). Significantly positive associations with all LBP variables were seen for hypointense disc signals, reduced disc height, and Modic changes. All disc “abnormalities” except protrusion were moderately associated with LBP during the past year. Conclusion. Most degenerative disc “abnormalities” were moderately associated with LBP. The strongest associations were noted for Modic changes and anterolisthesis. Further studies are needed to define clinical relevance.

Intensive, dynamic back-muscle exercises, conventional physiotherapy, or placebo-control treatment of low-back pain : a randomized, observer-blind trial

In a randomized, observer-blind trial, 150 men and women, aged 21-64 years, with chronic/subchronic low-back pain, followed one of these three treatment regimens: 1) intensive, dynamic back-muscle exercises; 2) conventional physiotherapy, including isometric exercises for the trunk and leg muscles; and 3) placebo-control treatment involving semihot packs and light traction. Eight treatment sessions were given during the course of 4 weeks, each session lasting 1 hour. The short-term effect was evaluated at the end of the treatment period and 1 month later, and the long-term effect at 6 and 12 months. The evaluations included recording of changes in pain level and assessment of overall treatment effect, which were indicated on visual interval scales. Subgroups of patients could be identified according to their treatment responses: physiotherapy was the superior treatment for the male participants, whereas the intensive back exercises appeared to be most efficient for the female participants. Patients with moderate or hard physical occupations tended toward a better response with physiotherapy, whereas intensive back exercises seemed most effective for those with sedentary/light job functions.

Modic changes and their associations with clinical findings

It is believed that disc degeneration (DD) is, in general, only mildly associated with low back pain (LBP). MRI-identified Modic changes (MC), probably a late stage of DD, are relatively strongly associated with LBP but it is not known if people with MC also have a specific clinical profile. The purpose of this study was to investigate if the clinical findings differ in people with Modic changes (MC) as compared to those with only degenerative disc findings or none at all. In a population-based sample of 412 40-year-old Danes, information was collected independently with MRI, questionnaires and clinical examination. Three subgroups of people were created: those with both DD and MC, those with only DD, and those with neither DD nor MC. The clinical pattern was investigated for each subgroup in order to test the assumption that the clinical picture differs in the three groups. It was expected that people with both DD and MC would have a more pronounced clinical profile than those with only DD who, in turn, would differ from those with neither of these two MRI findings. Our findings were generally in concordance with our expectations. MC constitutes the crucial element in the degenerative process around the disc in relation to LBP, history, and clinical findings. People with DD and no MC only vaguely differ from those without. People with LBP and MC may deserve to be diagnosed as having specific LBP.

Are MRI-defined fat infiltrations in the multifidus muscles associated with low back pain?

BackgroundBecause training of the lumbar muscles is a commonly recommended intervention in low back pain (LBP), it is important to clarify whether lumbar muscle atrophy is related to LBP. Fat infiltration seems to be a late stage of muscular degeneration, and can be measured in a non-invasive manner using magnetic resonance imaging. The purpose of this study was to investigate if fat infiltration in the lumbar multifidus muscles (LMM) is associated with LBP in adults and adolescents.MethodsIn total, 412 adults (40-year-olds) and 442 adolescents (13-year-olds) from the general Danish population participated in this cross-sectional cohort study. People with LBP were identified through questionnaires. Using MRI, fat infiltration of the LMM was visually graded as none, slight or severe. Odds ratios were calculated for both age groups, taking into account sex, body composition and leisure time physical activity for both groups, and physical workload (in adults only) or daily bicycling (in adolescents only).ResultsFat infiltration was noted in 81% of the adults but only 14% of the adolescents. In the adults, severe fat infiltration was strongly associated with ever having had LBP (OR 9.2; 95% CI 2.0–43.2), and with having LBP in the past year (OR 4.1; 1.5–11.2), but there was no such association in adolescents. None of the investigated moderating factors had an obvious effect on the OR in the adults.ConclusionFat infiltration in the LMM is strongly associated with LBP in adults only. However, it will be necessary to quantify these measurements objectively and to investigate the direction of this link longitudinally in order to determine if the abnormal muscle is the cause of LBP or vice versa.

A prospective, randomized 5-year follow-up study of functional restoration in chronic low back pain patients

Abstract A functional restoration (FR) program, dealing with a combination of intensive physical and ergonomic training, psychological pain management, and patient education, was tested in two randomized, parallel group studies. In one of these patients following the FR program were compared with a non-treated control group (project A), and in the other with patients on two less intensive treatment programs (project B). A total of 238 chronic low back pain patients participated in the two studies, 106 entering project A and 132 project B. Patients from the two projects were comparable except that the patients in project A were recruited from all over the country, whereas patients in project B all were living in and around Copenhagen. Thirteen patients never started any treatment, and 20 patients (9%) dropped out during the treatment period. Of the 207 who completed treatment, 89% returned a mailed questionnaire 5 years later. This was the case for 55% of the drop-outs. The questions referred to work situation, pain level, activities of daily living, days of sick leave, contact with health care professionals, physical activity, use of medication, and a subjective overall assessment. The results show that in project A the treated group reported significantly fewer contacts with the health care system and significantly fewer days of sick leave over the 5-year follow-up period compared to the control group. In all other parameters, including work ability, there was no statistically significant difference between the two groups. In project B, patients treated in the FR program did significantly better in most measured parameters, except in leg pain, use of pain medication and sport activity, where no significant differences were found between groups. The overall result shows a positive long-term effect of the FR program, but it also shows the necessity of testing a given treatment in different projects and designs, among other things due to statistical variations.

An epidemiologic study of MRI and low back pain in 13-year-old children.

Study Design. Cross-sectional cohort study of a general population. Objective. To describe associations between “abnormal” lumbar magnetic resonance imaging (MRI) findings and low back pain (LBP) in 13-year old children. Summary and Background Data. Very little is known about the distribution of lumbar MRI findings and how they are associated with LBP in youngsters. Methods. Disc abnormalities, as well as nerve root compromise, endplate changes, and anterolisthesis were identified from MRI studies of 439 children. LBP was identified from structured interviews. Associations are presented as odds ratios (OR). Results. Signs of disc degeneration were noted in approximately 1/3 of the subjects. Reduced signal intensity and irregular nucleus shape in the upper 3 lumbar discs were significantly associated with LBP within the last month (OR, 2.5–3.6), whereas reduced signal intensity and disc protrusion at L5–NS1 were associated with seeking care (OR, 2.8 and 7.7, respectively). Endplate changes in relation to the L3 discs were associated with LBP month and seeking care (OR, between 9.7 and 22.2). Anterolisthesis at L5 was associated with seeking care (OR, 4.3). There were obvious differences between genders: degenerative disc changes in the upper lumbar spine were more strongly associated with LBP in boys, while disc abnormalities in the lower lumbar spine were more strongly associated with seeking care in girls. Conclusions. In children, degenerative disc findings are relatively common, and some are associated with LBP. There appears to be a gender difference. Disc protrusions, endplate changes, and anterolisthesis in the lumbar spine were strongly associated with seeking care for LBP.

Lumbar Curve, Trunk Muscles, and Line of Gravity with Different Heel Heights

The influence of different heel heights on the lumbar curve, pelvic inclination, trunk muscle activity, and the position of the line of gravity was examined in 18 healthy women. They were examined while standing on heel-supports, being 4.5 cm elevated, at the level of and 2.5 cm lower than the support of the forefoot, respectively (Figure 1). Each examination was preceeded by one-hour adaptation to a corresponding shoe type. With increasing heel height, the lumbar lordosis and the pelvis inclination were decreased. The back and abdominal muscles did not alter their activities. The position of the line of gravity kept the distance from the forefoot almost constant, but the ankle joint was shifted towards the line of gravity with increasing heel height.

Neck collar, "act-as-usual" or active mobilization for whiplash injury? A randomized parallel-group trial.

Study Design. Randomized, parallel-group trial. Objective. To compare the effect of 3 early intervention strategies following whiplash injury. Summary of Background Data. Long-lasting pain and disability, known as chronic whiplash-associated disorder (WAD), may develop after a forced flexion-extension trauma to the cervical spine. It is unclear whether this, in some cases disabling, condition can be prevented by early intervention. Active interventions have been recommended but have not been compared with information only. Methods. Participants were recruited from emergency units and general practitioners within 10 days after a whiplash injury and randomized to: 1) immobilization of the cervical spine in a rigid collar followed by active mobilization, 2) advice to “act-as-usual,” or 3) an active mobilization program (Mechanical Diagnosis and Therapy). Follow-up was carried out after 3, 6, and 12 months postinjury. Treatment effect was measured in terms of headache and neck pain intensity (0–10), disability, and work capability. Results. A total of 458 participants were included. At the 1-year follow-up, 48% of participants reported considerable neck pain, 53% disability, and 14% were still sick listed at 1 year follow-up. No significant differences were observed between the 3 interventions group. Conclusion. Immobilization, “act-as-usual,” and mobilization had similar effects regarding prevention of pain, disability, and work capability 1 year after a whiplash injury.

The effect of body position and axial load on spinal canal morphology: an MRI study of central spinal stenosis.

Study Design. A method comparison study. Objective. To investigate the effect of body position and axial load of the lumbar spine on disc height, lumbar lordosis, and dural sac cross-sectional area (DCSA). Summary of Background Data. The effects of flexion and extension on spinal canal diameters and DCSA are well documented. However, the effects of axial loading, achieved by upright standing or by a compression device, are still unclear. Methods. Patients with lumbar spinal stenosis were examined in 2 separate studies, including 16 and 20 patients, respectively. In section 1, magnetic resonance imaging (MRI) scans were performed during upright standing and supine positions with and without axial load. In section 2, MRI scans were performed exclusively in supine positions, one with flexion of the lumbar spine (psoas-relaxed position), an extended position (legs straight), and an extended position with applied axial loading. Disc height, lumbar lordosis, and DCSA were measured and the different positions were compared. Results. In section 1, the only significant difference between positions was a reduced lumbar lordosis during standing when compared with lying (P = 0.04), most probably a consequence of precautions taken to secure immobility during the vertical scans. This seemingly makes our standing posture less valuable as a standard of reference. In section 2, DCSA was reduced at all 5 lumbar levels after extension, and further reduced at 2 levels after adding compression (P < 0.05). Significant reductions of disc height were found at 3 motion segments and of DCSA at 11 segments after compression, but these changes were never seen in the same motion segment. Conclusion. Horizontal MRI with the patient supine and the legs straightened was comparable to vertical MRI whether axial compression was added or not. Extensionwas the dominant cause rather than compression in reducing DCSA. Axial load was not considered to have a clinically relevant effect on spinal canal diameters.

Acute stress response and recovery after whiplash injuries. A one‐year prospective study

Chronic whiplash‐associated disorder (WAD) represents a major medical and psycho‐social problem. The typical symptomatology presented in WAD is to some extent similar to symptoms of post traumatic stress disorder. In this study we examined if the acute stress reaction following a whiplash injury predicted long‐term sequelae. Participants with acute whiplash‐associated symptoms after a motor vehicle accident were recruited from emergency units and general practitioners. The predictor variable was the sum score of the impact of event scale (IES) completed within 10 days after the accident. The main outcome‐measures were neck pain and headache, neck disability, general health, and working ability one year after the accident. A total of 737 participants were included and completed the IES, and 668 (91%) participated in the 1‐year follow‐up. A baseline IES‐score denoting a moderate to severe stress response was obtained by 13% of the participants. This was associated with increased risk of considerable persistent pain (OR=3.3; 1.8–5.9), neck disability (OR=3.2; 1.7–6.0), reduced working ability (OR=2.8; 1.6–4.9), and lowered self‐reported general health one year after the accident. These associations were modified by baseline neck pain intensity. It was not possible to distinguish between participants who recovered and those who did not by means of the IES (AUC=0.6). In conclusion, the association between the acute stress reaction and persistent WAD suggests that post traumatic stress reaction may be important to consider in the early management of whiplash injury. However, the emotional response did not predict chronicity in individuals.