STUDY DESIGN: Prospective case series. OBJECTIVE: To examine the relation between improved disability and changes in abdominal and lumbar multifidus (LM) thickness using ultrasound imaging following spinal manipulative therapy (SMT) in patients with low back pain (LBP). BACKGROUND: Although there is a growing body of literature demonstrating physiologic effects following the application of SMT, few studies have attempted to correlate these changes with clinically relevant outcomes. METHODS: Eighty-one participants with LBP underwent 2 thrust SMT treatments and 3 assessment sessions within 1 week. Transversus abdominis (TrA), internal oblique (IO), and LM muscle thickness was assessed during each session, using ultrasound imaging of the muscles at rest and during submaximal contractions. The Modified Oswestry Disability Index was used to quantify participants’ improvement in LBP-related disability. Stepwise hierarchical multiple linear regression and repeated-measures analysis of variance were performed to examine the multivariate relationship between change in muscle thickness and clinical improvement over time. RESULTS: After controlling for the effects of age, sex, and body mass index, change in contracted LM muscle thickness was predictive of improved disability at 1 week (P = .02). As expected, larger increases in contracted LM muscle thickness at 1 week were associated with larger improvements in LBP-related disability. Contrary to our hypothesis, significant decreases in both contracted TrA and IO muscle thickness were observed immediately following SMT; but these changes were transient and unrelated to whether participants experienced clinical improvements. CONCLUSION: These findings provide evidence that clinical improvement following SMT is associated with increased thickening of the LM muscle during a submaximal task. LEVEL OF EVIDENCE: Prognosis, level 4.

J Orthop Sports Phys Ther 2011;41(6):389-399, Epub 6 April 2011. doi:10.2519/jospt.2011.3632

KEY WORDS: low back pain, muscle contraction, transversus abdominis, ultrasound

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To describe the clinical outcomes following outpatient physical therapy for postoperative rehabilitation in 4 categories of shoulder surgery. Furthermore, we sought to determine if differences in outcomes between genders existed. BACKGROUND: Improving the quality of care for patients following shoulder surgery requires an understanding of the clinical outcomes resulting from current clinical practice. METHODS: This study included 856 patients (43.7% female; mean ± SD age, 51.8 ± 14.2 years) who received outpatient physical therapy following shoulder surgery. Standardized methods for classification of patients to type of shoulder surgery and collection of outcome variables were used. Data were gathered from 57 therapists working in 12 clinics. Patients included had been classified into 1 of 4 surgical categories: repair of a unidirectional instability, rotator cuff repair, rotator cuff repair with a subacromial decompression, or subacromial decompression alone. Descriptive statistics were calculated for baseline characteristics of patients in each surgical category. For all patients, scores on the Disability of the Arm Shoulder and Hand (DASH) questionnaire and a numeric pain rating scale (NPRS) were obtained at the initial and final physical therapy visits, and the change between visits was calculated. Data on number of physical therapy sessions and length of stay (LOS) were collected. For each surgical category, independent-samples t tests were used to determine differences between genders for each initial and final clinical outcome of pain and disability, change scores, utilization of visits, and LOS. The percentage of patients who achieved a minimal clinically important difference (MCID) on the DASH was also determined for each surgical group. For each gender in each surgical category, paired t tests were used to determine if patients achieved significant change in pain and disability. RESULTS: Means for each clinical outcome for the initial and final pain and disability scores, change scores, and the percentage of patients that achieved an MCID are provided. Significant differences were observed between genders for clinical outcomes. In the group treated with unilateral instability repair, women reported significantly greater initial disability than men, and their DASH change scores were significantly greater. In the group that had rotator cuff repairs, women reported significantly greater disability initially and at the final follow-up. In the group that had rotator cuff repairs combined with subacrominal decompression, women reported significantly greater disability initially and greater change in DASH scores. Females also reported greater change in their pain scores than males (P<.05). There were no significant differences between men and women in the subacromial decompression group (P<.05). There were no significant differences between genders for number of physical therapy visits or LOS. Men and women in each surgical category achieved clinically meaningful and statistically significant improvement for pain and disability during treatments (P<.01). Greater than 75% of patients achieved an MCID (15 points) on the DASH score in each surgical category (range, 75.6%-94.5%). CONCLUSIONS: Differences were observed between men and women in 4 postoperative surgical categories in each of the clinical outcomes but not for number of physical therapy visits or LOS. Statistically significant and clinically meaningful pain and disability improvements were reported for each gender within each shoulder category. Results from this study may help therapists estimate the prognosis of males and females receiving nonstandardized postoperative physical therapy in 4 different shoulder surgical categories. LEVEL OF EVIDENCE: Therapy, level 2b.

J Orthop Sports Phys Ther 2010;40(1):20-29, Epub 7 December 2009. doi:10.2519/jospt.2010.3043

KEY WORDS: DASH, instability, rotator cuff

STUDY DESIGN: Clinical measurement, reliability study. OBJECTIVES: To investigate the improvements in precision when averaging multiple measurements of percent change in muscle thickness of the transversus abdominis (TrA) and lumbar multifidus (LM) muscles. BACKGROUND: Although the reliability of TrA and LM muscle thickness measurements using rehabilitative ultrasound imaging (RUSI) is good, measurement error is often large relative to mean muscle thickness. Additionally, percent thickness change measures incorporate measurement error from both resting and contracted conditions. METHODS: Thirty volunteers with nonspecific low back pain participated. Thickness measurements of the TrA and LM muscles were obtained using RUSI at rest and during standardized tasks. Percent thickness change was calculated with the formula (thickness_contracted – thickness_rest/thickness_rest). Standard error of measurement (SEM) quantified precision when using 1 or a mean of 2 to 6 consecutive measurements. RESULTS: Compared to when using a singlemeasurement, SEM of both the TrA and LM decreased by nearly 25% when using a mean of 2 measures, and by 50% when using the mean of 3 measures. Little precision was gained by averaging more than 3 measurements. CONCLUSION: When using RUSI to determine percent change in TrA and LM muscle thickness, intraexaminer measurement precision appears to be optimized by using an average of 3 consecutive measurements.

J Orthop Sport Phys Ther 2009;39(8):604-611 Epub 24 June 2009. doi:10.2519/jospt.2009.3088

KEY WORDS: abdominal muscles, lumbar spine, reliability, ultrasonography