Hamilton Hall

1999 Young Investigator Research Award Winner : Prognostic Factors for Time Receiving Workers' Compensation Benefits in a Cohort of Patients With Low Back Pain

Study Design. Prospective inception cohort study. Objective. To develop a prognostic model that predicts time receiving workers’ compensation benefits for low back pain claimants. Summary of Background Data. As the cost and difficulty of managing low back pain escalate, any predictor of outcome is advantageous. Methods. To obtain the outcome and predictor variables, patient data from two separate databases were linked: a clinical database and an administrative (Ontario workers’ compensation) database. Claimants injured between January 1 and December 31, 1994, were included and observed for 1 year from the date of accident. The outcome variable was cumulative number of calendar days receiving benefits. Results. Multivariable Cox proportional hazards regression (forward stepwise) showed eight significant predictors; five were associated with increased time receiving benefits compared with their reference groups: 1) working in the construction industry, 2) older age, 3) lag time from injury to treatment, 4) pain referred into the leg, and 5) three or more positive Waddell nonorganic signs. Three predictors were associated with reduced time receiving benefits: 1) higher values of questionnaire score, 2) intermittent pain, and 3) a previous episode of back pain. A predictive score was calculated to categorize claimants as at high or low risk for chronicity. When an arbitrary cutoff point was set at the 75th percentile of predictive score, negative predictive value was 94%. Conclusion. This research identified eight factors for time receiving workers’ compensation benefits among claimants with low back pain. This model discriminates between high- and low-risk claimants. Few low-risk claimants continued to receive benefits for more than 3 months.

A test to measure lift capacity of physically impaired adults : Part 1. Development and reliability testing

Study Design. Two laboratory studies end one field study evaluated the safety and test-retest reliability of a new test of lift capacity. The first two studies were conducted in a carefully controlled laboratory selling. The first study investigated the safely and intra-rater reliability of the EPIC Lift Capacity test protocol with healthy adult subjects. The second study assessed the safety and inter-rater reliability of the test with disabled subjects. The third study was conducted in the field with 65 evaluates and investigated the safety and intra-rater reliability of the test with healthy adult subjects. Objective. To assess the safety and reliability of a new test of lift capacity. Summary of Background Data. A new test of lift capacity baa been developed. Test development occurred within the context of ergonomic standards and guidelines of the major professional associations and public agencies that govern test development in the United States. Methods. In study no, 1, 26 healthy subjects participated. In study no. 2, 14 disabled subjects participated. In study no. 3, 318 healthy subjects participated. After subjects underwent basic screening and warm-up, the EPIC Lift Capacity test was administered, Ono to 2 weeks later, the test was administered again. Correlations between the times of testing were calculated. Results. No subjects were Injured, Hamstring soreness the next day that resolved without complication was reported by some healthy subjects. None of the disabled subjects reported new symptoms. Conclusion. The safety and reliability of the EPIC Lift Capacity test was adequately demonstrated in a laboratory setting and across multiple field sites with evaluators who have varying types and degrees of professional preparation.

Spine rehabilitation. Secondary and tertiary nonoperative care.

To achieve desirable behavioral outcomes, physicians treating spinal pain patients should be aware of appropriate algorithms for conservative care. Lower cost secondary rehabilitation can be effective if deconditioning, severity of physical symptoms, surgical equivocation, or psychosocial barriers to recovery are not present. Patients who have extended disability in excess of 6 months, recognized psychosocial barriers (depression, substance abuse, personality disorders, secondary gain), or severe deconditioning have a better prognosis with tertiary care.

Low Back Pain Prognosis: Structured Review of the Literature

The purpose of this paper was to review and appraise pertinent articles to gain a better understanding of critical methodological issues necessary to properly design a high-quality back pain prognosis study. The review concentrated on back pain prognosis studies with epidemiologically sound designs focusing on work-disability outcomes and utilizing survival analytic methods. Nine papers were reviewed. There were few well-designed studies that achieved good scientific quality with minimal flaws. The outcomes were well defined in each paper. The age and sex characteristics of the cohorts were described in six papers and an adequate description of the study site occurred in five papers. All papers employed suitable mathematical/statistical techniques, but only one paper discussed accuracy and predictive value. No paper addressed the issue of reproducibility of the predictor variables or the final model. Most papers derived models that were clinically sensible, and the ease of use for clinicians was high. A recommended course of action for use by future patients/therapists in prognostication was rarely documented. To date, prognosis has been an inadequately studied aspect of the continuum from back injury to recovery. Researchers and clinicians interested in prognosis research need to overcome the limitations of past designs and address the methodological guidelines outlined to improve the quality of future prognosis studies.

A systematic review of clinical pathways for lower back pain and introduction of the Saskatchewan Spine Pathway.

Study Design. Systematic review of spine care pathways and case study of the Saskatchewan Spine Pathway (SSP). Objective. (1) What are the differences between clinical pathways and clinical guidelines? (2) Are there examples of clinical pathways in the management of lower back pain (LBP)? Is there evidence that they are successful? (3) What is the SSP, and what are its key features? Summary of Background Data. Adherence to evidence-based guidelines for LBP produces superior outcomes and may improve efficiency by reducing unnecessary imaging, ineffective treatments, and inappropriate surgical referrals. A clinical pathway is an attempt to bridge the “translation gap” between guidelines and clinical practice. Methods. A qualitative review was performed for question 1. For question 2, a systematic review of the English language literature was performed for articles published through March 31, 2011. A case study is provided for question 3. Results. (1) Evidence for clinical pathways is mainly derived from guidelines, but pathways are distinguished by several features including the coordination of multidisciplinary care, facilitation of communication among care providers, resources for ongoing quality improvements, and a central focus on the patient experience. (2) Five articles describing four clinical pathways met the a priori criteria, but none tested comparative effectiveness. (3) The SSP is unique in that it is (a) inclusive for all types of LBP, (b) based on a classification system, (c) patient-focused mostly at primary care rather than in specialized clinics, (d) implemented in the health care system of a geopolitically defined region, and (e) includes all of the defining features of modern care pathways. Conclusion. Several clinical pathways for LBP have been described, but effectiveness has not been tested. Clinical Recommendations. Clinical pathways for LBP need to be further developed and investigated as a means to facilitate guidelines-concordant practice and improve patient outcomes. Level of evidence: Insufficient. Recommendation: Weak.

Spontaneous onset of back pain.

OBJECTIVES To assess the frequency with which patients attribute low back pain to spontaneous onset. DESIGN A consecutive sample of two distinct groups of patients seeking treatment for back pain: those without need to identify cause (study group, n = 4,689) and those required to report a specific event to qualify for benefits paid for by a third party (compensated group, n = 6,687). SETTING Active exercise-based back pain rehabilitation clinics. SUMMARY OF BACKGROUND DATA Research on the natural history of back pain has revealed frequent reports of spontaneous recovery, usually within 8-12 weeks after onset. There is little comparable literature pertaining to the report of spontaneous onset. METHODS Data were collected for two groups of consecutive patients who attended for initial assessments of their back pain at 16 Canadian Back Institute locations, between May 1, 1994 and February 28, 1995. Patient responses were collected using a standardized, professionally administered questionnaire. RESULTS In the group without need to identify cause, 66.7% of patients could not identify an event producing their symptoms. For those required to report a specific event, only 9.8% of patients failed to attribute cause. Multivariate logistic regression revealed that the required-to-report group was approximately 15 times more likely to report an event (odds ratio = 14.95; 95% confidence interval = 13.44, 16.65) than the study group; those pursuing litigation were more than 2.5 times more likely to report a causative event (odds ratio = 2.68; 95% confidence interval = 2.09, 3.49). CONCLUSIONS Back pain occurred spontaneously in approximately 67% of patients seeking treatment in the study group. The authors consider spontaneous onset to be part of the natural history of back pain for this group.

Provider, payor, and patient outcome expectations in back pain rehabilitation

Return to work is used routinely to define successful back pain treatment. This study examined how the patient and three professional groups defined success for each of five categories of patients: not sponsored and working, sponsored and working, sponsored on modified duty, sponsored and off work for less than 10 weeks, and sponsored and off work for more than 10 weeks. The groups sampled were treating staff (n = 98), referring physicians (n = 98), third-party sponsors (n = 133), and patients (n = 648) representing all five patient categories. Each group provided a priority ranking for six objectives of treatment: Return to Work, Pain Control, Functional Improvement, Increased Strength and Range of Movement, Positive Attitude Shift, and Acquired Knowledge. The results indicated that the work status of the patient had a significant effect on the ranking of objectives by the treating staff and third-party sponsors. Physicians and patients considered pain control most important regardless of the patient category. Success in back pain rehabilitation is defined by different criteria. The determination of successful outcome must consider the patients circumstances and acknowledge the perspective of the individual who is defining success.

Controversy. Low back school. Education or exercise

Few interventions have conclusively changed the natural history of low back pain with respect to recovery once an episode has begun, or have prevented future recurrence. Variations of the low back school, an educational approach, have become increasingly popular but their efficacy remains controversial. Dr. Hall is emphatic that patient education is a less than perfect but nonetheless an important approach. Dr. Hadler believes that these programs re-enforce the misconception that low back pain is an injury rather than a commonly occurring life event, such as the flu, and should be handled but not overtreated. He offers a more tempered opinion.

Contribution of nonspinal comorbidity to low back pain outcomes.

ObjectiveTo determine the involvement of comorbidity to outcomes in a cohort of acute mechanical low back pain patients. MethodsIncident low back pain cases (n=7077) in the acute or subacute phase assessed between January 1, 1999 and December 31, 2001 were included. Patients were categorized into 1 of 2 groups on the basis of their current medical history: (1) those with at least 1 of 7 medical histories considered (Comorbidity Group, n=539), or (2) those with only low back pain (Back Pain Group, n=6538). Main outcome measures were: change in perceived function and visual analog scale (VAS) pain rating from initial assessment to discharge, and total number of treatment days. ResultsThere were no baseline statistically significant differences in VAS pain rating, questionnaire score, or symptom duration between groups. Odds ratios (ORs) were adjusted to reflect age and sex differences between groups. Logistic regression analysis revealed no statistically significant difference for change in functional score (OR=1.002) between groups; there were marginal differences in change in VAS pain rating (OR=1.08) and total number of treatment days (OR=1.006). χ2 analysis revealed no statistically significant differences in medication use, global pain rating, or pain control ability posttreatment, between groups. DiscussionSignificant ORs were barely greater than 1.00 and were likely the result of the large sample size. The clinical course for comorbid patients, who may seem more complicated at the start of treatment, is just as favorable.

Guidelines for the identification of barriers to rehabilitation of back injuries.

Not all patients with back pain recover within the expected natural recovery period. Addressing only the physical component and ignoring the psychosocial may lead to treatment failure. Recognition of typical circumstances that may become barriers to rehabilitation enhances the recovery process. Barriers to rehabilitation and questions to help determine their existence are discussed. Asking pertinent questions enables clinicians to identify those who may need redirection. This re-direction may reduce treatment time, resulting in cost savings for the third party payer and a reduction in health care dollars spent on rehabilitation. Most importantly, resolution of possible barriers and rapid recovery allows the patient to return to a normal lifestyle.