The Nordic back pain subpopulation program: can low back pain patterns be predicted from the first consultation with a chiropractor? A longitudinal pilot study

Does a Diagnostic Classification Algorithm Help to Predict the Course of Low Back Pain? A Study of Danish Chiropractic Patients With 1-Year Follow-up

BACKGROUND

A diagnostic classification algorithm, "the Petersen classification," consisting of 12 categories based on a standardized examination protocol, was developed for the primary purpose of identifying clinically homogeneous subgroups of individuals with low back pain (LBP).

OBJECTIVES

To investigate whether a diagnostic classification algorithm is associated with activity limitation and LBP intensity at follow-up assessments of 2 weeks, 3 months, and 1 year, and whether the algorithm improves outcome prediction when added to a set of known predictors.

METHODS

This was a prospective observational study of 934 consecutive adult patients with new episodes of LBP who were visiting chiropractic practices in primary care and categorized according to the Petersen classification. Outcomes were disability and pain intensity measured with questionnaires at 2 weeks and 3 months, and 1-year trajectories of LBP based on weekly responses to text messages. Associations were analyzed with linear and logistic regression models. In a subgroup of patients, the numbers of visits to primary and secondary care were described.

RESULTS

The Petersen classification was statistically significantly associated with all outcomes (P<.001) but explained very little of the variance (R² = 0.00-0.05). Patients in the nerve root involvement category had the most pain and activity limitation and the most visits to primary and secondary care. Patients in the myofascial pain category were the least affected.

CONCLUSION

The Petersen classification was not helpful in determining individual prognosis in patients with LBP receiving usual care in chiropractic practice. However, patients should be examined for potential nerve root involvement to improve prediction of likely outcomes.

LEVEL OF EVIDENCE

Prognosis, level 1b. J Orthop Sports Phys Ther 2018;48(11):837-846. Epub 8 May 2018. doi:10.2519/jospt.2018.8083.

Differences in Outcomes of Patients Treated by Male vs Female Chiropractors

OBJECTIVE

The purpose of this study was to compare treatment outcomes of low back pain patients depending on the sex of the treating doctor of chiropractic (DC).

METHODS

For this study, 1095 adult patients with no manual therapy in the prior 3 months were recruited. Pretreatment pain levels (Numeric Rating Scale for pain [NRS]), Oswestry Disability Index (ODI), and patient demographic details were recorded. The NRS and Patient Global Impression of Change were assessed after 1 week and 1, 3, 6, and 12 months. The ODI was completed up to 3 months. The χ² test compared sex of the DC with the proportion of patients "improved" at all time points and with baseline categorical variables. The unpaired t test compared changes in NRS and ODI scores between patients of male and female DCs.

RESULTS

Female DCs saw proportionally more acute patients (P = .012). Patients of male DCs presented more often with radiculopathy (P = .007). There were no differences in NRS and ODI baseline scores between male and female DCs' patients. At 1 week and 3 and 12 months, significantly more patients of female DCs reported improvement and they had greater decreases in NRS and ODI scores at 1 week. Removing acute patients from the data, there were no longer differences in outcome.

CONCLUSIONS

Significant differences in treatment outcome in favor of female DCs was no longer present on removal of the acute subgroup from the data. This suggests that patient outcome is influenced by other factors, such as chronicity, rather than sex of the treating DC.

Adding Psychosocial Factors Does Not Improve Predictive Models for People With Spinal Pain Enough to Warrant Extensive Screening for Them at Baseline

BACKGROUND

Chiropractors throughout the world by and large focus on patients with musculoskeletal complaints who are generally in good health. Currently, it is widely accepted that neck pain and low back pain are best understood as biopsychosocial phenomena.

OBJECTIVE

The purpose of this study was to determine whether certain psychosocial factors provide added value for predicting recovery.

DESIGN

This was a prospective, multicenter, chiropractic, practice-based cohort study in Belgium and the Netherlands.

METHODS

A total of 917 participants, 326 with neck pain and 591 with low back pain, completed self-administered questionnaires at baseline and at 3, 6, and 12 months. They provided information on several demographic, biomedical, and psychosocial variables. Lasting perceived recovery was used as the outcome measure, that is, recovery at all follow-up assessments from 3 months on. Twenty-seven potential predictors of outcome were used to build the predictive model. Stepwise, backward generalized estimating equation regression models were used to take into account the clustering of participants within practices. For assessment of the added value of psychosocial variables, 2 model fit indexes were compared.

RESULTS

After the addition of psychosocial variables, predictors in the final model for neck pain included occupational status, body mass index, duration of complaints, previous treatment, and participant expectations (the model fit was marginally improved from 0.684 to 0.695 for the area under the curve and from 65.0% to 66.1% for the percentage correctly predicted). In the final model for low back pain, the selected predictors included country of treatment, age, duration of complaints, previous imaging, and somatization (the area under the curve changed from 0.669 to 0.715, and the percentage correctly predicted changed from 68.6% to 69.5%). Only a minority of participants had high scores on psychological variables.

LIMITATIONS

The reliability and validity of lasting recovery as an outcome measure have not been tested. The cohort needs to be seen as a convenience sample. Selection bias, therefore, not be ruled out. There are no indications, however, that patients with complex psychosocial profiles were excluded from this study.

CONCLUSIONS

Psychosocial variables provided little added value for predicting outcome in people who had neck pain or low back pain and sought chiropractic care. Therefore, chiropractors should not screen extensively for them at baseline. With regard to the identification of the small subgroup of people with high scores on psychosocial variables and a high risk for chronic pain, further investigation is needed.

Do number of days with low back pain and patterns of episodes of pain have similar outcomes in a biopsychosocial prediction model?

PURPOSES

We used two different methods to classify low back pain (LBP) in the general population (1) to assess the overlapping of individuals within the different subgroups in those two classifications, (2) to explore if the associations between LBP and some selected bio-psychosocial factors are similar, regardless which of the two classifications is used.

METHOD

During 1 year, 49- or 50-year-old people from the Danish general population were sent fortnightly automated text messages (SMS-Track) asking them if they had any LBP in the past fortnight. Responses for the whole year were then classified into two different ways: (1) In relation to the number of days with LBP in the preceding year (0, 1-30, and >30), (2) In relation to the frequency and duration of episodes of LBP (more or less never pain, episodic, and more or less constant pain). Some bio-psychosocial factors, collected with a questionnaire at baseline 9 years earlier, were entered into regression models to investigate their associations with the subgroups of the two classifications of LBP and the results compared.

RESULTS

The percentage of agreement between categories of the two classification systems was above 68 % (Kappa 0.7). Despite the large overlap of persons in the two classification groups, the patterns of associations with the two types of LBP definitions were different in the two classification groups. However, none of the estimates were significantly different when the variables were compared across the two classifications.

CONCLUSION

Different classification systems of LBP are capable of bringing forth different findings. This may help explain the lack of consistency between studies on risk factors of LBP.

Clinical examination findings as prognostic factors in low back pain: a systematic review of the literature

Background

There is a strong tradition of performing a clinical examination of low back pain (LBP) patients and this is generally recommended in guidelines. However, establishing a pathoanatomic diagnosis does not seem possible in most LBP patients and clinical tests may potentially be more relevant as prognostic factors. The aim of this review of the literature was to systematically assess the association between low-tech clinical tests commonly used in adult patients with acute, recurrent or chronic LBP and short- and long-term outcome.

Methods

MEDLINE, Embase, and MANTIS were searched from inception to June 2012. Prospective clinical studies of adult patients with LBP with or without leg pain and/or signs of nerve root involvement or spinal stenosis, receiving non-surgical or no treatment, which investigated the association between low-tech clinical tests and outcome were included. Study selection, data extraction and appraisal of study quality were performed independently by two reviewers.

Results

A total of 5,332 citations were retrieved and screened for eligibility, 342 articles were assessed as full text and 49 met the inclusion criteria. Due to clinical and statistical heterogeneity, qualitative synthesis rather than meta-analysis was performed. Associations between clinical tests and outcomes were often inconsistent between studies. In more than one third of the tests, there was no evidence of the tests being associated with outcome. Only two clinical tests demonstrated a consistent association with at least one of the outcomes: centralization and non-organic signs.

Conclusions

For most clinical tests in LBP there is not consistent evidence for an association with outcome. Centralization and non-organic signs are exceptions from that. None of the other clinical tests have been investigated in confirmatory studies and study quality is generally low. There is a need for hypothesis testing studies designed specifically to investigate the prognostic value of the clinical tests, and a need for standardization of the performance and interpretation of tests.

Electronic supplementary material

The online version of this article (doi:10.1186/s12998-015-0054-y) contains supplementary material, which is available to authorized users.

Pregnancy-related low back pain and pelvic girdle pain approximately 14 months after pregnancy - pain status, self-rated health and family situation

Background

Pelvic girdle pain (PGP) in pregnancy is distinct from pregnancy-related low back pain (PLBP). However, women with combined PLBP and PGP report more serious consequences in terms of health and function. PGP has been estimated to affect about half of pregnant women, where 25% experience serious pain and 8% experience severe disability. To date there are relatively few studies regarding persistent PLBP/PGP postpartum of more than 3 months, thus the main objective was to identify the prevalence of persistent PLBP and PGP as well as the differences over time in regard to pain status, self-rated health (SRH) and family situation at 12 months postpartum.

Methods

The study is a 12 month follow-up of a cohort of pregnant women developing PLBP and PGP during pregnancy, and who experienced persistent pain at 6 month follow-up after pregnancy. Women reporting PLBP/PGP (n = 639) during pregnancy were followed up with a second questionnaire at approximately six month after delivery. Women reporting recurrent or persistent LBP/PGP at the second questionnaire (n = 200) were sent a third questionnaire at 12 month postpartum.

Results

A total of 176 women responded to the questionnaire. Thirty-four women (19.3%) reported remission of LBP/PGP, whereas 65.3% (n = 115) and 15.3% (n = 27), reported recurrent LBP/PGP or continuous LBP/PGP, respectively. The time between base line and the 12 months follow-up was in actuality 14 months. Women with previous LBP before pregnancy had an increased odds ratio (OR) of reporting ‘recurrent pain’ (OR = 2.47) or ‘continuous pain’ (OR = 3.35) postpartum compared to women who reported ‘no pain’ at the follow-up. Women with ‘continuous pain’ reported statistically significant higher level of pain at all measure points (0, 6 and 12 months postpartum). Non-responders were found to report a statistically significant less positive scoring regarding relationship satisfaction compared to responders.

Conclusions

The results from this study demonstrate that persistent PLBP/PGP is a major individual and public health issue among women 14 months postpartum, negatively affecting their self-reported health. However, the perceived relationship satisfaction seems to be stable between the groups.

Patient characteristics in low back pain subgroups based on an existing classification system. A descriptive cohort study in chiropractic practice

Sub-grouping of low back pain (LBP) is believed to improve prediction of prognosis and treatment effects. The objectives of this study were: (1) to examine whether chiropractic patients could be sub-grouped according to an existing pathoanatomically-based classification system, (2) to describe patient characteristics within each subgroup, and (3) to determine the proportion of patients in whom clinicians considered the classification to be unchanged after approximately 10 days. A cohort of 923 LBP patients was included during their first consultation. Patients completed an extensive questionnaire and were examined according to a standardised protocol. Based on the clinical examination, patients were classified into diagnostic subgroups. After approximately 10 days, chiropractors reported whether they considered the subgroup had changed. The most frequent subgroups were reducible and partly reducible disc syndromes followed by facet joint pain, dysfunction and sacroiliac (SI)-joint pain. Classification was inconclusive in 5% of the patients. Differences in pain, activity limitation, and psychological factors were small across subgroups. Within 10 days, 82% were reported to belong to the same subgroup as at the first visit. In conclusion, LBP patients could be classified according to a standardised protocol, and chiropractors considered most patient classifications to be unchanged within 10 days. Differences in patient characteristics between subgroups were very small, and the clinical relevance of the classification system should be investigated by testing its value as a prognostic factor or a treatment effect modifier. It is recommended that this classification system be combined with psychological and social factors if it is to be useful.

Predictors of improvement in patients with acute and chronic low back pain undergoing chiropractic treatment

OBJECTIVES

The purpose of this study was to investigate outcomes and prognostic factors in patients with acute or chronic low back pain (LBP) undergoing chiropractic treatment.

METHODS

This was a prognostic cohort study with medium-term outcomes. Adult patients with LBP of any duration who had not received chiropractic or manual therapy in the prior 3 months were recruited from multiple chiropractic practices in Switzerland. Participating doctors of chiropractic were allowed to use their typical treatment methods (such as chiropractic manipulation, soft tissue mobilization, or other methods) because the purpose of the study was to evaluate outcomes from routine chiropractic practice. Patients completed a numerical pain rating scale and Oswestry disability questionnaire immediately before treatment and at 1 week, 1 month, and 3 months after the start of treatment, together with self-reported improvement using the Patient Global Impression of Change.

RESULTS

Patients with acute (<4 weeks; n = 523) and chronic (>3 months; n = 293) LBP were included. Baseline mean pain and disability scores were significantly (P < .001) higher in patients with acute LBP. In both groups of patients, there were significant (P < .0001) improvements in mean scores of pain and disability at 1 week, 1 month, and 3 months, although these change scores were significantly greater in the acute group. Similarly, a greater proportion of patients in the acute group reported improvement at each follow-up. The most consistent predictor was self-reported improvement at 1 week, which was independently associated with improvement at 1 month (adjusted odds ratio [OR], 2.4 [95% confidence interval, 1.3-4.5] and 5.0 [2.4-10.6]) and at 3 months (2.9 [1.3-6.6] and 3.3 [1.3-8.7]) in patients with acute and chronic pain, respectively. The presence of radiculopathy at baseline was not a predictor of outcome.

CONCLUSIONS

Patients with chronic and acute pain reporting that they were "much better" or "better" on the Patient Global Impression of Change scale at 1 week after the first chiropractic visit were 4 to 5 times more likely to be improved at both 1 and 3 months compared with patients who were not improved at 1 week. Patients with acute pain reported more severe pain and disability initially but recovered faster. Patients with chronic and acute back pain both reported good outcomes, and most patients with radiculopathy also improved.

The use of weekly text messaging over 6 months was a feasible method for monitoring the clinical course of low back pain in patients seeking chiropractic care

OBJECTIVE

This study critically evaluates a new method of collecting frequent data using mobile phones and text messages. Fluctuating conditions such as low back pain (LBP) need frequent monitoring to describe the clinical course in detail and to account for individual and subgroup variations.

STUDY DESIGN AND SETTING

In this multicentre prospective observational study, 262 subjects with nonspecific LBP were followed with weekly text messages for 6 months, with the question "How many days this previous week has your low back pain been bothersome?" The text replies were instantly recorded in a data file to be merged with baseline and follow up data (age, gender, pain intensity, duration, and self- rated health) collected through ordinary questionnaires. The response rate, user-friendliness, and compliance of this method were evaluated.

RESULTS

The mean response rate for the text messages throughout the study was 82.5% and was unaffected by season. The method was found to be user friendly. Dropout was not affected by age and gender, but compliance was possibly somewhat affected by outcome.

CONCLUSION

Weekly text messages are a useful method of data collection to examine the clinical course of LBP in the primary care sector.

Clustering patients on the basis of their individual course of low back pain over a six month period

Background

Several researchers have searched for subgroups in the heterogeneous population of patients with non-specific low back pain (LBP). To date, subgroups have been identified based on psychological profiles and the variation of pain.

Methods

This multicentre prospective observational study explored the 6- month clinical course with measurements of bothersomeness that were collected from weekly text messages that were sent by 176 patients with LBP. A hierarchical cluster analysis, Ward's method, was used to cluster patients according to the development of their pain.

Results

Four clusters with distinctly different clinical courses were described and further validated against clinical baseline variables and outcomes. Cluster 1, a "stable" cluster, where the course was relatively unchanged over time, contained young patients with good self- rated health. Cluster 2, a group of "fast improvers" who were very bothered initially but rapidly improved, consisted of patients who rated their health as relatively poor but experienced the fewest number of days with bothersome pain of all the clusters. Cluster 3 was the "typical patient" group, with medium bothersomeness at baseline and an average improvement over the first 4-5 weeks. Finally, cluster 4 contained the "slow improvers", a group of patients who improved over 12 weeks. This group contained older individuals who had more LBP the previous year and who also experienced most days with bothersome pain of all the clusters.

Conclusions

It is possible to define clinically meaningful clusters of patients based on their individual course of LBP over time. Future research should aim to reproduce these clusters in different populations, add further clinical variables to distinguish the clusters and test different treatment strategies for them.