Study Design: A prospective longitudinal study. Background: Diastasis recti abdominis (DRA) is defined as an increase in the inter-recti distance (IRD), or width of the linea alba. It is a common occurrence in women postpartum. Little information exists on the short- and long-term recovery of IRD and the relationship between changes in IRD and the functional performance of the abdominal muscles. Objectives: To investigate the natural recovery of IRD and abdominal muscle strength and endurance in women between 7 weeks and 6 months postpartum, and to examine the relationship between IRD and abdominal muscle function. Methods: Forty postpartum (25–37 years of age) and 20 age-matched, nulliparous females participated. IRD was measured at 4 locations (upper and lower margin of the umbilical ring, and 2.5 cm above and below the umbilical ring) with a 7.5-MHz linear ultrasound transducer. Trunk flexion and rotation strength and endurance were measured with manual muscle testing and curl-ups. Evaluation was conducted at 4 to 8 weeks and 6 to 8 months after childbirth in postpartum women, and only once for the nulliparous female controls. Results: During follow-up, the IRD at 2.5 cm above the umbilical ring and at the upper margin of the umbilical ring decreased (P = .013 and P = .002, respectively). The strength and static endurance of the abdominal muscles improved over time (P<.05). A negative correlation between IRD and abdominal muscle function at 7 weeks and 6 months postpartum was found (r = 0.34 to 0.51; P<.05, except for trunk flexion strength at 6 months postpartum [P = .064]). In addition, IRD changes between 7 weeks and 6 months postpartum were correlated with improvement in trunk flexion strength (Spearman rho = 0.38, P = .040). At 6 months after childbirth, postpartum women had greater mean ± SD IRDs at all 4 locations (from cranial to caudal: 1.80 ± 0.72, 2.13 ± 0.65, 1.81 ± 0.62, and 1.16 ± 0.58 cm) than those of nulliparous females (0.85 ± 0.26, 0.99 ± 0.31, 0.65 ± 0.23, and 0.43 ± 0.17 cm) (all P<.001). All abdominal strength and endurance measurements were less than those of nulliparous females (all P<.001). Conclusions: The IRD and abdominal muscle function of postpartum women improved but had not returned to normal values at 6 months after childbirth. Future research is essential to explore the need for intervention and, if needed, the effectiveness of specific intervention to reduce the size of IRD in postpartum women. J Orthop Sports Phys Ther 2011;41(6):435–443, Epub 2 February 2011. doi:10.2519/jospt.2011.3507

Purpose. To examine the relative reliability and absolute reliability of the Berg Balance Scale (BBS) and the Postural Assessment Scale for Stroke Patients (PASS) in chronic stroke patients. Method. A total of 52 mild to moderate stroke patients, who had a stroke more than 6 months previously, participated in the study. Both balance measures were administered twice, seven days apart, to the patients. A relative reliability index (intra-class correlation coefficient, ICC_2,1) was used to examine the level of agreement between test and retest. Absolute reliability indices, including the Bland and Altman method, the standard error of measurement (SEM), and the smallest real differences (SRD), were used to define the extent to which a balance score varies on test-retest measurements. Results. Test-retest agreements were high (ICC_2,1: BBS = 0.98; PASS = 0.97), indicating excellent agreement from a relative perspective. The SEM of the BBS and PASS, representing the smallest change threshold that indicates a real improvement for a group of individuals, were 2.4 and 1.1, respectively. The SRD of the BBS and PASS were 6.7 and 3.2, respectively, exhibiting the smallest change threshold that indicates a real improvement for a single individual. Conclusions. The test-retest agreements of the BBS and PASS were high in mild to moderate chronic stroke patients. The thresholds of both measures to detect real change are acceptable in research and clinical settings.

Objective. This study examined test-retest agreement and measurement errors for the Rivermead Mobility Index (RMI) and the Mobility subscale of the Stroke Rehabilitation Assessment of Movement (M-STREAM) in patients with chronic stroke and mild to moderate disability. The authors aimed to determine the level of agreement between test and retest as well as the extent to which a mobility score varies on test-retest measurements. Methods. Both mobility measures were tested on 50 chronic stroke patients twice, 7 days apart. Intraclass correlation coefficient (ICC_2,1), a relative reliability index, was used to examine the level of agreement between test and retest. Absolute reliability indices, including the standard error of measurement and the smallest real differences, were used to determine the extent to which the mobility scores varied due to chance variation in measurement. Results. Test-retest agreements were excellent for both mobility measures. The standard errors of measurement of the RMI and the M-STREAM, representing the smallest change threshold that indicates a real improvement (beyond measurement error) for a group of individuals, were 0.8 and 1.5, respectively. The smallest real differences of the RMI and the M-STREAM, exhibiting the smallest change threshold that indicates a real improvement for a single individual, were 2.2 and 4.2, respectively. Conclusion. The RMI and the M-STREAM have high agreement between the test-retest measurements with acceptable measurement errors due to variation in measurement. The 2 measures can be used by clinicians and researchers to assess the mobility performance and monitor changes over time in stroke patients.

[Purpose] The purpose of this study was to investigate the effects of 6 weeks sling exercise training for clients with low back pain on the levels of pain, disability, muscular strength and endurance. [Subjects and Methods] Twelve chronic LBP subjects participated in this study. Subjects were randomly divided into a control group and a training group. Subjects in the training group performed sling exercise training for six weeks, and participants in the control group did not perform any exercise. [Results] Pain, disability levels and muscular strength significantly improved in the training group, but not in the control group. The left multifidus showed a significant improvement in muscular endurance, measured as the slope of the median frequency after training. [Conclusion] Six weeks of sling exercise training was effective at reducing pain intensity, and improving the disability level and trunk muscular strength of subjects with low back pain.

Objective: To examine the test-retest reliability, convergent and predictive validity and responsiveness of the modified Emory Functional Ambulation Profile (mEFAP) in assessing gait function in stroke patients undergoing rehabilitation. Subjects: Forty subacute stroke inpatients were enrolled in the validity and responsiveness study. Twenty chronic patients participated in the reliability study. Setting: Rehabilitation department of a medical centre. Design: In the validity and responsiveness study, patients were tested using the mEFAP, 10-m walking speed test, Barthel Index and Rivermead Mobility Index at admission and at discharge. For the reliability study, the patients completed the mEFAP twice one week apart. Results: The patients' performances on the mEFAP were moderately to highly correlated with results of the 10-m walking speed test and Rivermead Mobility Index (absolute correlation coefficients ≥0.67), indicating good convergent validity. Patients' performance on the mEFAP at admission was moderately correlated with the Barthel Index and Rivermead Mobility Index scores at discharge (Spearman's rank correlation coefficients=-0.52 and-0.78, respectively), indicating good predictive validity. The standardized response mean of the mEFAP was 1.1 (P<0.0001), suggesting good responsiveness. The intraclass correlation coefficient ICC(3,1) for the mEFAP was 0.997, indicating excellent test-retest reliability. Conclusions: Our results provide strong evidence that the mEFAP has good reliability, validity and responsiveness for assessing stroke patients undergoing rehabilitation. The mEFAP is a useful scale for measuring walking function and recovery in stroke patients.

[Purpose] To explore the differences in bilateral trunk muscle activation between chronic stroke patients and healthy controls, this study investigated the symmetry index and cross-correlation of trunk muscles during trunk flexion and extension movements. This study also assessed the differences in trunk reposition error between groups and the association between trunk reposition error and bilateral trunk muscle activation. [Subjects and Methods] Fifteen stroke patients and 15 age- and gender-matched healthy subjects participated. Bilateral trunk muscle activations were collected by electromyography during trunk flexion and extension. Trunk reposition errors in trunk flexion and extension directions were recorded by a Qualisys motion capture system. [Results] Compared with the healthy controls, the stroke patients presented lower symmetrical muscle activation of the bilateral internal oblique and lower cross-correlation of abdominal muscles during trunk flexion, and lower symmetry index and cross-correlation of erector spinae in trunk extension. They also showed a larger trunk extension reposition error. A smaller trunk reposition error was associated with higher cross-correlation of bilateral trunk muscles during trunk movements in all subjects. [Conclusion] Trunk muscle function during symmetrical trunk movements and trunk reposition sense were impaired in the chronic stroke patients, and trunk position sense was associated with trunk muscle functions. Future studies should pay attention to symmetrical trunk movements as well as trunk extension position sense for patients with chronic stroke.