Introduction: Previous studies have reported controversial associations between exercise and neck or shoulder pains in adolescents. In this study we evaluated the relationships between physical activity or sedentary activities and neck or occipital pain (NOP) or shoulder pain (SP) in a representative sample of adolescents.

Methods: The study population consisted of adolescents belonging to the Northern Finland Birth Cohort 1986 (n=5993). Associations of physical activity level, total sitting time, and different kinds of sedentary activities with NOP and SP were analyzed at 15–16 years of age using logistic regression. “Reporting NOP and SP” (not seeking medical help) and “Consultation for NOP and SP” were assessed separately in girls, but were combined in boys because of low prevalence of “Consultations”.

Results: Almost half of the girls and one third of the boys reported NOP or SP, and 5% of girls and 2% of boys reported “Consultation for NOP or SP” during the past six months. High level of physical activity associated with increased prevalence of both “Consultation for NOP” and “Consultation for SP” in girls, but not in boys. Prolonged sitting was associated with high prevalence of NOP and SP in girls, and NOP in boys. Of various sedentary activities, TV watching and reading books associated with NOP in girls, whereas playing or working with a computer associated with NOP in boys. In girls, TV watching also associated with “Reporting SP”.

Discussion: Both prolonged sitting and high level of physical activity seem to be related to NOP and SP among adolescents.

Introduction: Both physical activity and inactivity have been suggested as risk factors for LBP, but the current evidence is conflicting. In this study we evaluated how the level of leisure time physical activity and amount of sitting are associated with LBP in a general population of adolescents.

Methods: The study population consisted of 5999 boy and girl members of the Northern Finland 1986 Birth Cohort who responded to mailed questions at the age of 15–16 years. LBP during the past six months was classified as “No LBP”, “Reporting LBP” (not seeking medical help), or “Consultation for LBP”. Odds ratios and 95% confidence intervals obtained by multinomial logistic regression were adjusted for smoking and BMI.

Results: Being physically very active (more than six hours of brisk physical activity per week) was associated with increased prevalence of “Consultation for LBP” in both genders, and with “Reporting LBP” in girls, compared to being moderately active (2–3 hours of brisk physical activity per week). High amount of sitting associated with “Consultation for LBP” and “Reporting LBP” in girls, but not in boys.

Discussion: Very active participation in physical activities in both genders and high amount of sitting in girls, irrespective of the level of physical activity, were associated with reported LBP. Perhaps encouraging adolescents to physically moderately active lifestyle could diminish LBP. In addition, avoiding excessive sitting-based activities such as television watching and playing video games may be recommendable among girls.

Introduction: Only few studies have investigated the role of sleep disturbances in adolescents’ musculoskeletal pains.

Methods: A two-year follow-up by postal questionnaires was made for the Northern Finland Birth Cohort 1986 at the ages of 16 and 18 years (n=1773). The outcome measures were six-month period prevalences of self-reported neck pain (NP) and low back pain (LBP) (“Reporting Pain” and “Consultation for Pain”). Sleep disturbances were categorised into three groups (major, minor and no sleep disturbances) based on average hours spent sleeping, and whether or not the subject suffered from nightmares, tiredness and sleeping problems. The odds ratios (OR) and 95% confidence intervals (CI) for were obtained from logistic regression and adjusted for all previously suggested risk factors.

Results: Sleep disturbances at 16 years predicted NP and LBP at the age of 18. Among the adolescents initially without LBP, major sleep disturbances at 16 predicted LBP at 18 in both girls (OR 2.6; 95% CI 1.2 to 5.5) and boys (2.7; 1.1 to 6.7). Similarly, among those initially without NP, major sleep disturbances at 16 years predicted NP at 18 years in girls (3.9; 1.6 to 9.4) but not in boys.

Discussion: Sleep disturbances were an independent risk factor for LBP and NP in adolescence. Possible mechanisms may include decreased time for muscle relaxation during disturbed sleep, co-morbidity with psychological distress, or activation of inflammatory mediators. Perhaps some musculoskeletal pains could be prevented – at least partially – by ensuring that adolescents have sufficient quality and quantity of sleep.

Introduction: Modic changes are vertebral endplate changes visible in magnetic resonance imaging (MRI), which associate with degenerative intervertebral disc disease. Twin studies suggest that intervertebral disc degeneration and low back pain may be primarily explained by genetic factors. There are, however, no studies on genetic factors in Modic changes.

Materials and methods: Eleven variations in eight genes (COL9A2, COL9A3, COL11A2, IL1A, IL1B, IL6, MMP-3 and VDR) were genotyped in an occupational cohort of 159 male train engineers and 69 male paper mill workers. All the study subjects were MRI scanned and evaluated for Modic changes.

Results: Out of 228 subjects studied, 128 (56%) were found to have Modic change at one or more disc levels. 15% of them had exclusively Modic type I while 32% had exclusively Modic II changes. 10% of the subjects had both type I and type II changes. When single nucleotide polymorphisms (SNPs) were analyzed independently, none of them significantly associated with Modic changes. However, when the gene-gene interactions were evaluated IL1A and MMP-3 polymorphisms together associated with type II Modic changes (OR 3.2, 95% CI 1.2–8.5; p = 0.038). Furthermore, IL-1 gene cluster together with MMP-3 polymorphism associated significantly with type II Modic changes (OR = 8.14, 95% CI 1.72–38.44; p = 0.008).

Discussion: This is the first study evaluating the role of genetic factors in relation to Modic changes. Genetic variations in IL-1 cluster and MMP-3 gene were found together to associate significantly with type II Modic changes.

Purpose: The aim of this study was to investigate whether distress alone or in combination with personality traits associates with low back pain (LBP) in adolescence.

Materials and methods: Oulu Back Study (OBS) is a sub-cohort of the Northern Finland 1986 Birth Cohort. Data was collected at 16 and 18 years. The response rate was 69% (1987/2969). Incident cases reported LBP at 18 but not at 16, whereas persistent cases reported back pain at both time points. Distress (GHQ-12) and personality traits (hostility, optimism-pessimism, trait anxiety) were inquired at 18. Logistic regression analysis, stratified for gender, with adjustment for BMI, physical activity, smoking, parents’ socioeconomic status, sedentary hours, and sleep disturbances at 16 years was used. Additionally, the psychological determinants were mutually adjusted in the final analysis.

Results: Distress was associated independently with incident LBP among boys (highest quartile vs. lowest: OR 2.47; 95% CI 1.17–5.21), whereas none of the psychological determinants were significant in incident pain among girls. Trait anxiety was associated with persistent LBP among girls (OR 2.27; 1.09–4.75), and of borderline significance with boys’ persistent pain (OR 2.40; 0.99–5.84). The combination of trait anxiety and distress (highest quartiles) associated significantly with both incident and persistent pain in both genders (OR range from 1.95 to 2.36), whereas of the other combinations of distress with personality traits only pessimism associated with persistent LBP among boys (OR 2.05).

Conclusions: Perceived distress and trait anxiety, alone and especially combined with each other, associate with self-reported LBP in adolescence.

Introduction: We have shown that an IL6 haplotype (GGGA) associates with intervertebral disc disease (IDD) characterized by sciatica. However, its prognostic value for IDD is not known.

Materials and methods: DNA from 153 sciatica patients, who participated in a randomized controlled trial of periradicular infiltration, was analyzed for IL6 variations: c.1–597G> A, c.1–572G> C, c.1–174G> C, and c.486T> A (Genebank #NM_000600.1). Patients recorded back and leg pain intensity and duration (number of days with pain), Oswestry disability, and back-related sick leaves. Repeated measures ANCOVA with adjustment for age, gender and physical work load was used. Square root transformations of outcome data at one, two and three years after the intervention were used for skewed variables.

Results: The prevalence of the GGGA haplotype was 9% (14/153). Data was available from 10 (sick leaves) to 13 (VAS) subjects with and from 107 to 124 subjects without the haplotype. The groups did not differ with respect to pain intensities, or disability. Days with back and leg pain and sick leaves were significantly higher among subjects with the IL6 haplotype (p=0.024, 0.002 and 0.022, respectively). An interaction of the IL6 haplotype and physical work load was significant for duration of back and leg pain and sick leaves (p=0.010, 0.004 and 0.018, respectively).

Discussion: This is the first observation of any prognostic genotype among sciatica patients. The IL6 haplotype GGGA predicted the number of days with back or leg pain, and sickness absence. Subjects with the IL6 haplotype may be more vulnerable when exposed to physically demanding job.

Aims: The purpose was to assess the effect of discec-tomy surgery on postural control, lumbar perception and reßex activation of paraspinal muscles during sudden upper limb loading. Methods: The study included 20 patients selected for an operation for chronic low back pain due to disc herniation and 15 controls without chronic back pain. The paraspinal muscle responses for upper limb loading during unexpected and expected conditions were measured by surface EMG. The ability to sense lumbar rotation was assessed in a previously validated motorized trunk rotation unit in the seated position. The postural control was measured with a vertical force platform. Pain, disability and depression scores were recorded. Results: Patients had poorer lumbar perception (P=0.012) and postural control (P< 0.05) than healthy control subjects. The postural control remained unchanged but lumbar perception (P=0.054) and the lumbar feed-forward control (P=0.043) improved after the surgery. Conclusions: This study demonstrated impaired lumbar proprioception and postural control in sciatica patients. During short-term follow-up after operative treatment, postural control does not seem to change, but impaired lumbar proprioception and feed-forward control of paraspinal muscles seem to recover.

Aims: To assess the paraspinal muscle innervation and endurance in LSSMethods: Study included 25 patients with clinically and radiologically diagnosed LSS. Electromyography (EMG) of the paraspinal muscles was performed at the L3 to S1 levels bilaterally using a concentric needle. At least 20 insertions were analysed from each muscle to detect abnormal spontaneous activity associated with axonal damage (þbrillation potentials, positive sharp waves and complex repetitive discharges). Paraspinal muscle activity during trunk ßexion-extension movement and muscle endurance during dynamic isoinertial back endurance test were assessed by surface EMG. Muscle fatigue was calculated using mean power frequency (MPF) analysis. Results: Abnormal þndings in needle EMG of the paraspinal muscles were observed in 18 out of the 22 (81.8%) examined patients. Abnormal ßexionextension activation of the paraspinal muscles was observed in all examined patients. The MPF change was signiþcantly smaller than in previously evaluated healthy subjects and non-speciþc CLBP patients (P< 0.001) not suffering from symptoms of LSS. Para-spinal muscle fatigability was not associated with the denervation of the muscles. Conclusions: Denervation and abnormal activation of lumbar paraspinal muscles are frequent þndings in non-operated LSS patients. The paraspinal muscle endurance of the patients was unexpectedly good

We used MRI to study a prospective series of 95 patients with inversion injuries of the ankle and no fracture on plain radiographs. We found an incidence of bone bruises of 27%, but these made no difference to the time of return to work, limitation of walking or physical activity, or the clinical outcome scores at three months.

We conclude that bone bruises have very little clinical significance after inversion injuries of the ankle.

Magnetic resonance imaging was used to analyse the patellofemoral relationships during the first 30 degrees of knee flexion in women with recurrent patellar dislocation. The patellofemoral joints were imaged both sagittally and axially with the knee flexed 0 degrees, 10 degrees, 20 degrees, and 30 degrees. At the beginning of knee flexion the sulcus angle was greater than in unaffected women, the lateral patellofemoral angle was smaller, the patella displaced further laterally, tilted more laterally and the congruence angle was directed more laterally. At 30 degrees of knee flexion these differences were less marked than at 0 degree to 10 degrees. Logistic regression analysis showed that the sulcus angle at 10 degrees of knee flexion was the most diagnostic feature, indicating that there is an anatomical predisposition to recurrent dislocation and that pathological patellar tracking starts from the beginning of flexion. Traditional sunrise radiographic films taken at 25 degrees to 30 degrees knee flexion clearly miss diagnostically important information.