SYNOPSIS: Degeneration of the lumbar intervertebral discs (IVDs) is highly prevalent in adults and is nearly universal in the elderly population. Degenerative changes within, and adjacent to, the IVDs are likely to contribute to a variety of pain syndromes; however, the exact association between these findings and symptoms remains speculative. Recent research has provided new information regarding the etiology, pathophysiology, and clinical relevance of degeneration of the IVD. This information will assist clinicians and researchers in understanding the development and clinical course of lumbar disc degeneration, as well as its potential impact upon patients seeking physical therapy care for back pain. The purposes of this clinical commentary are to review the structure and metabolic capacity of the normal and degenerative lumbar IVD, and to discuss factors that influence the onset and progression of disc degeneration. Lumbar magnetic resonance images will be used to illustrate the common findings associated with this condition. LEVEL OF EVIDENCE: Diagnosis, level 5.

J Orthop Sports Phys Ther. 2008;38(6):329-340, published online 12 March 2008. doi:10.2519/jospt.2008.2768

KEY WORDS: back pain, lumbar disc, MRI, rehabilitation

Current best evidence suggest that, when adjusting for risk, a substantial number of patients receiving outpatient physical therapy report good outcomes and have lower cost of care or frequency of adverse events when compared to pharmacologic or invasive procedures. In other words, physical therapy care, supported by the best available research evidence, is often a bargain when compared to other treatment approaches. However, a question that must be asked is, "How much do patients value their physical therapy care?"

J Orthop Sports Phys Ther 2008;38(2):34-35. doi:10.2519/jospt.2008.0113

KEY WORDS: patient-therapist relationship, value-based care

STUDY DESIGN: Observational, repeated measures design. OBJECTIVES: To determine the reliability of the apparent diffusion coefficient (ADC) calculated from diffusion-weighted magnetic resonance images (MRI) of the nuclear region of lumbar intervertebral discs (IVDs), to investigate the differences in the ADC based upon T₂-signal intensity, and to examine the test-retest variation in these measures obtained from subjects undergoing serial, diffusion-weighted MRI scans. BACKGROUND: Impaired diffusion of water within the lumbar IVD is a central characteristic of degenerative disc disease. Diffusion-weighted MRI scans can provide quantitative estimates of water diffusion and may be useful to evaluate the physiologic effects of healing or the change in hydration related to interventions such as traction, manual therapy, or exercise on normal and degenerative lumbar IVDs. METHODS AND MEASURES: Thirty subjects underwent T₂ -weighted and diffusion-weighted lumbar MRI scans. Twenty-one of these subjects underwent a second diffusion-weighted MRI scan 4 to 7 weeks after the initial scan. The ADC was calculated from midsagittal diffusion-weighted images for the IVDs of L1-2 to L5-S1.  To assess reliability, repeated measures of the ADC were performed on the first 16 scans. The T₂-signal of the nuclear region of each disc was classified as hyperintense, intermediate, or hypointense, and its relationship to the mean ADC of the nuclear region was determined. Test-retest variation in the ADC was described using the coefficient of variation (CV), plus or minus the width of the 95% confidence interval of the standard error of measurement (SEM). RESULTS: Intraclass correlation coefficients for estimates of intrarater and interrater reliability ranged from 0.95 to 0.99 and the SEM ranged from 0.006 to 0.026 X 10^-3 mm²/s. The mean ADC was significantly greater for hyperintense IVDs compared to intermediate and hypointense IVDs. The CV plus or minus the 95% CI of the SEM between scans ranged from 9.0% to 13.6% for all discs, 6.1% to 10.1% for hyperintense discs, and 13.1% to 23.7% for intermediate discs. The prevalence of hypointense discs was too low to make meaningful judgments about their normal degree of variation over time. CONCLUSION: The ADC of the nuclear region of the lumbar IVDs may be reliably measured from diffusion-weighted images. Degenerative discs had lower mean ADC values than normal discs but demonstrated greater variation between scans. Diffusion-weighted imaging may be a useful procedure to assess change in diffusion of water in lumbar discs that occurs over time.

J Orthop Sports Phys Ther. 2008;38(2):42-49, published online 21 September 2007. doi:10.2519/jospt.2008.2631 

KEY WORDS: back pain, degenerative disc disease, lumbar spine, MRI

Study Design: Psychometric evaluation of a cross-sectional survey. Objectives: To determine the validity of measures obtained from the MedRisk Instrument for Measuring Patient Satisfaction With Physical Therapy Care (MRPS) to differentiate between patient satisfaction with internal and external factors. Background: Self-report measures that sample a variety of items provide clinicians with an array of information that may assist in assessing patient satisfaction. An important measurement characteristic of these instruments is the ability to discriminate between different factors that may influence patient reports of satisfaction with care, ie, discriminant validity. In previous work, exploratory factor analysis suggested that the MRPS questionnaire has a 2-factor structure: ‘‘internal,’’ relating to the patient-therapist interaction, and ‘‘external,’’ describing nontherapist issues such as admissions and clinic environment. Methods and Measures: One thousand four hundred forty-nine adult patients completed the MRPS questionnaire upon finishing their course of outpatient physical therapy treatment. Discriminant validity of the 2-factor model was assessed using confirmatory factor analysis. The measures from the 2 factors were then evaluated for reliability by calculating the standard error of measurement (SEM), and for concurrent validity by correlating the mean score of the factors and individual items to global measures of satisfaction. Results: Confirmatory factor analysis supported a good to excellent model fit for the internal factor (7 items) and external factor (3 items). The SEM for the 2 factors was 0.19 and 0.24, indicating a low degree of measurement error. Both factors had high significant correlation with global measures of satisfaction (internal, r = 0.83 and 0.80; external, r = 0.71 and 0.71). All individual items within the 2 factors had significant correlations with global measures ranging from r =0.33 to 0.80. Conclusions: Our findings provide evidence of discriminant and concurrent validity of the 2-factor solution for the MRPS questionnaire for the sample that was tested. This 2-factor solution yields measures that are relatively free of error and may discriminate between internal and external factors influencing patient satisfaction. Patients who complete their course of physical therapy report that the professional interaction between the therapist and patient, especially the meaningful exchange of relevant information, is critical for patient satisfaction with care. The generalizability of our data to patients who do not complete their physical therapy care or who are receiving care in other health care environments is unknown.

J Orthop Sports Phys Ther. 2005;35(1):24-32. doi: 10.2519/jospt.2005.1471

Key Words: instrument validation, questionnaire, self-report, survey