Anterior and posterior rectus abdominis sheath stiffness in relation to diastasis recti: Abdominal wall training or not?

INTRODUCTION: This study explores the anatomical relation of the rectus abdominis muscles with the anterior and posterior rectus sheaths. The elastic behavior of these fascial sheets is also assessed. Both of these analyses form an anatomic-biomechanical basis for diagnosis and treatment, especially in relation to diastasis recti abdominis (DRA). METHOD: Fundamental observational, biomechanical study. Seven post-mortem, embalmed human specimens were dissected. The abdominal muscles and the fascial sheets of the abdominal wall were dissected. 4 × 4 cm samples of the anterior and posterior rectus sheaths were loaded in longitudinal and transverse direction, while recording elongation by means of a displacement sensor. The main outcome measures were anatomical descriptions and elongation of fascia samples in mm (mean and standard ±â€¯deviation). RESULTS: In longitudinal direction the posterior rectus sheath samples stretched over 1.67 ±â€¯0.48 mm, while in transverse direction the mean stretch was 0.29 ±â€¯0.18 mm (p = 0.001). In contrast, no significant difference between longitudinal (0.78 ±â€¯0.43 mm) and transversal displacement (0.50 ±â€¯0.23 mm) was observed in the anterior rectus sheath (p = 0.56). DISCUSSION AND CONCLUSION: The posterior rectus sheath is functionally more related to the transverse abdominis muscle than to the rectus abdominis muscle. From this connection, in combination with the specific stiffness of the posterior fascia in the lateral direction, it is assumed that the transverse abdominis muscles play an important role in the etiology but also in reduction of DRA. The transverse abdominis and rectus abdominis muscles collaborate in support of the abdominal wall.

Prognosis and course of work-participation in patients with chronic non-specific low back pain: a 12-month follow-up cohort study.

OBJECTIVE: To investigate the clinical course of, and prognostic factors for, work-participation in patients with chronic non-specific low back pain. METHODS: A total of 1,608 patients with chronic non-specific low back pain received a multidisciplinary therapy and were evaluated at baseline and 2-, 5- and 12-month follow-ups. Recovery was defined as absolute recovery if the patient worked 90% of his contract hours at follow-up. Potential factors were identified using multivariable logistic regression analysis. RESULTS: Patients reported a mean increase in work-participation from 38% at baseline to 82% after 12 months. Prognostic factors for ≥ 90% work-participation at 5 months were being married (odds ratio (OR) 1.72 (95% confidence interval (95% CI) 1.12-2.65)), male (OR 1.99 (95% CI 1.24-3.20)), a higher score on disability (OR 1.00 (95% CI 0.997-1.02)) and physical component scale (Short-Form 36 (SF-36)) (OR 1.05 (95% CI 1.02-1.07)), previous rehabilitation (OR 1.85 (95% CI 1.14-2.98)), not receiving sickness benefits (OR 0.52 (95% CI 0.24-1.10)) and more work-participation (OR 4.86 (95% CI 2.35-10.04)). More work-participation (OR 5.22 (95% CI 3.47-7.85)) and male sex (OR 1.79 (95% CI 1.25-2.55)) were also prognostic factors at 12-month follow-up. CONCLUSION: At 12 months 52% of patients reported ≥ 90% work-participation. The strongest prognostic factor was more work-participation at baseline for the recovery of chronic non-specific low back pain.

Prognostic factors and course for successful clinical outcome quality of life and patients' perceived effect after a cognitive behavior therapy for chronic non-specific low back pain: A 12-months prospective study.

This study investigates the clinical course of and prognostic factors for quality of life (Short Form 36 items Health survey (SF-36)) and global perceived effect (GPE) in patients treated for chronic non-specific low back pain at 5 and 12-months follow-up. Data from a prospective cohort (n = 1760) of a rehabilitation center were used, where patients followed a 2-months cognitive behavior treatment. The outcome 'improvement in quality of life (SF-36)' was defined as a 10% increase in score on the SF-36 at follow-up compared with baseline. On the GPE scale, patients who indicated to be 'much improved' were coded as 'clinically improved'. Multivariable logistic regression analysis included 23 baseline characteristics. At 5-months follow-up, scores on the SF-36 Mental Component Scale (SF-36; MCS) and the Physical Component Scale (SF-36; PCS) had increased from 46.6 (SD 10.3) to 50.4 (SD 9.8) and from 31.9 (SD 7.1) to 46.6 (SD 10.3), respectively. At 5-months follow-up, 53.0% of the patients reported clinical improvement (GPE) which increased to 60.3% at 12-months follow-up. The 10% improvement in quality of life (SF-36 MCS) at 5-months follow-up was associated with patient characteristics and psychological factors. At 5-months follow-up, the 10% improvement in quality of life (SF-36 PCS) and GPE was associated with patient characteristics, physical examination, work-related factors and psychological factors; for GPE, an association was also found with clinical status. At 12-months follow-up GPE was associated with patient characteristics, clinical status, physical examination and work-related factors. The next phase in this prognostic research is external validation of these results.

Prognosis and course of disability in patients with chronic nonspecific low back pain: a 5- and 12-month follow-up cohort study.

BACKGROUND: Few data are available on the course of and predictors for disability in patients with chronic nonspecific low back pain (CNSLBP). OBJECTIVE: The purpose of this study was to describe the course of disability and identify clinically important prognostic factors of low-back-pain-specific disability in patients with CNSLBP receiving multidisciplinary therapy. DESIGN: A prospective cohort study was conducted. METHODS: A total of 1,760 patients with CNSLBP who received multidisciplinary therapy were evaluated for their course of disability and prognostic factors at baseline and at 2-, 5-, and 12-month follow-ups. Recovery was defined as 30% reduction in low back pain-specific disability at follow-up compared with baseline and as absolute recovery if the score on the Quebec Back Pain Disability Scale (QBPDS) was ≤20 points at follow-up. Potential prognostic factors were identified using multivariable logistic regression analysis. RESULTS: Mean patient-reported disability scores on the QBPDS ranged from 51.7 (SD=15.6) at baseline to 31.7 (SD=15.2), 31.1 (SD=18.2), and 29.1 (SD=20.0) at 2, 5, and 12 months, respectively. The prognostic factors identified for recovery at 5 and 12 months were younger age and high scores on disability and on the 36-Item Short-Form Health Survey (SF-36) (Physical and Mental Component Summaries) at baseline. In addition, at 5-month follow-up, a shorter duration of complaints was a positive predictor, and having no comorbidity and less pain at baseline were additional predictors at 12-month follow-up. LIMITATIONS: Missing values at 5- and 12-month follow-ups were 11.1% and 45.2%, respectively. CONCLUSION: After multidisciplinary treatment, the course of disability in patients with CNSLBP continued to decline over a 12-month period. At 5- and 12-month follow-ups, prognostic factors were identified for a clinically relevant decrease in disability scores on the QBPDS.

Course and prognosis of recovery for chronic non-specific low back pain: design, therapy program and baseline data of a prospective cohort study.

BACKGROUND: There has been increasing focus on factors predicting the development of chronic musculoskeletal disorders. For patients already experiencing chronic non-specific low back pain it is also relevant to investigate which prognostic factors predict recovery. We present the design of a cohort study that aims to determine the course and prognostic factors for recovery in patients with chronic non-specific low back pain. METHODS/DESIGN: All participating patients were recruited (Jan 2003-Dec 2008) from the same rehabilitation centre and were evaluated by means of (postal) questionnaires and physical examinations at baseline, during the 2-month therapy program, and at 5 and 12 months after start of therapy. The therapy protocol at the rehabilitation centre used a bio-psychosocial approach to stimulate patients to adopt adequate (movement) behaviour aimed at physical and functional recovery. The program is part of regular care and consists of 16 sessions of 3 hours each, over an 8-week period (in total 48 hours), followed by a 3-month self-management program. The primary outcomes are low back pain intensity, disability, quality of life, patient's global perceived effect of recovery, and participation in work. Baseline characteristics include information on socio-demographics, low back pain, employment status, and additional clinical items status such as fatigue, duration of activities, and fear of kinesiophobia. Prognostic variables are determined for recovery at short-term (5 months) and long-term (12 months) follow-up after start of therapy. DISCUSSION: In a routine clinical setting it is important to provide patients suffering from chronic non-specific low back pain with adequate information about the prognosis of their complaint.

Differences in standing and forward bending in women with chronic low back or pelvic girdle pain: indications for physical compensation strategies.

STUDY DESIGN: This cohort study compares motion characteristics during forward bending of a group of chronic female patients either with low back pain (LBP) or pelvic girdle pain (PGP) and healthy subjects using computer-video analysis. OBJECTIVE: This study determines whether subcategories of back pain patients could be distinguished by motion characteristics of the pelvis and lumbar spine. SUMMARY OF BACKGROUND DATA: Compared with healthy subjects, patients with low back pain bend forward in distinct manners. Clustering these motion patterns into specific patient subgroups has been challenging since a basis for subcategorizing was lacking. Chronic LBP can be distinguished from PGP using specific evidence-based diagnostic tests. This allows comparing the motion characteristics of subgroups of chronic patients with either LBP or PGP. METHODS: Forward bending was recorded in both female patients groups and healthy female individuals, using a computer video analysis system. Trunk motion, pelvic tilt, and lumbar lordosis are represented as sagittal plane angles. From these angles, the relative contribution of the lumbar spine and hip joint to forward bending can be derived. RESULTS: Specific and discriminating motion characteristics were found between groups. During erect stance in the PGP group, the pelvis is significantly tilted backwards. At maximally forward bending, the ROM of the trunk is limited in all patient groups, but only the PGP group has significantly limited hip motion. During the initial part of forward bending, lumbar motion is increased in PGP patients and decreased in LBP patients. In the final part of forward bending contribution of the lumbar spine is increased in both patient groups. CONCLUSION: BP and PGP patients show specific, consistent, and distinct motion patterns. These motion patterns are assumed to be functional compensation strategies, following altered neuromuscular coordination.

Physical characteristics of women with severe pelvic girdle pain after pregnancy: a descriptive cohort study.

STUDY DESIGN: Descriptive cohort study. OBJECTIVE: This study aims to further elucidate the differences in physical characteristics of women with severe pregnancy-related pelvic girdle pain (PGP). SUMMARY OF BACKGROUND DATA: There is increasing interest in pelvic girdle pain (PGP). To our knowledge, this is the first study on a large population of patients with severe PGP, after pregnancy, based on high cutoff scores on diagnostic PGP tests. METHODS: Two hundred five patients were selected from the outpatient clinic of a rehabilitation center. Patients were divided in 3 inclusion groups based on the total number of positive scores on 5 diagnostic tests; i.e., active straight leg raise test, posterior pelvic pain provocation test, long dorsal sacroiliac ligament test, and hip abduction and adduction strength tests. These inclusion groups were related to the data on trunk strength test, general provocation tests, Quebec Back Pain Disability Scale (QBPDS) and activities of daily living. RESULTS: A typical pattern of PGP emerges from this study. The mean group score on the active straight leg raise, posterior pelvic pain provocation, and long dorsal sacroiliac ligament tests became higher when more than 3 inclusion tests were positive. Hip abduction and adduction strength became lower with more positive tests. The QBPDS score was overall high and significantly higher for 5 positive tests compared with 3 and 4 positive tests. This shows that the number of positive tests, the individual score on the diagnostic tests, and the QBPDS could all be an indicator for severity of PGP. Among the general pain provocation tests, both the passive hip flexion test and the upper and middle sacral thrust test scored high. The maximal isometric strength of trunk muscles was below the 10th percentile compared with women without complaints and was even less for 5 positive inclusion tests. It is confirmed that there is a typical order for difficulties with daily activities for PGP patients as follows (most difficult first): standing still, cycling, walking, sitting, and lying. CONCLUSION: The study shows that the level of severity in PGP can be adequately assessed by a combination of specific tests.

Reliability and validity of hip adduction strength to measure disease severity in posterior pelvic pain since pregnancy.

STUDY DESIGN: A cross-sectional analysis was performed in patients with posterior pelvic pain since pregnancy (PPPP). The strength of adduction of the hips was measured and compared with the scores of commonly used disease severity measures of lumbopelvic pain. OBJECTIVES: To assess the reliability and validity of using hip adduction strength as measure of disease severity in patients with PPPP. SUMMARY OF BACKGROUND DATA: Various tools are used to measure disease severity in PPPP; there is still a need for simple tests with high reliability and validity. METHODS: Intra- and intertester reliability of hip adduction strength measurement was assessed in two small groups of women with PPPP. Validity of hip adduction strength to measure disease severity was investigated in a group of 200 patients with PPPP by comparing the test scores with the medical history, scores on self-reported scales on disability, pain, and tiredness, pain provocation tests, and the active straight leg raise test. Responsiveness of hip adduction strength was assessed in a group of 75 patients with PPPP. Global impression of improvement, scored by the patient, was used as criterion standard. The responsiveness of the hip adduction strength was expressed as the standardized response mean and was compared with the responsiveness of the Quebec Back Pain Disability Scale. RESULTS: The intratester reliability for measuring hip adduction strength and the intraclass correlation coefficient were both 0.79. The intertester reliability for measurement of adduction strength and the intraclass correlation coefficient were also both 0.79. Hip adduction strength correlated as expected with all disease severity measures. Responsiveness of the hip adduction strength was large (standardized response mean = 0.93) and slightly less than that of the Quebec Back Pain Disability Scale (standardized response mean = 1.20). CONCLUSION: Hip adduction strength can be recommended to measure disease severity in PPPP, especially to describe groups of patients and to evaluate the course of the disease in groups as well as in individual patients. Decreased hip adduction strength appears to be caused by the inability to use the hip muscles rather than by weakness of the muscles.

Responsiveness of outcome measurements in rehabilitation of patients with posterior pelvic pain since pregnancy.

STUDY DESIGN: A cohort study was conducted. OBJECTIVE: To develop a test battery for evaluating the course of posterior pelvic pain since pregnancy. SUMMARY OF BACKGROUND DATA: Properly validated scales to evaluate the course of posterior pelvic pain since pregnancy are scarce. Moreover, the use of many tests would be too strenuous for the patient and has an unfavorable cost-benefit ratio. METHODS: The ability of 48 effect measures to detect clinically relevant changes over time (responsiveness) was tested in patients with posterior pelvic pain since pregnancy. In this test, 35 measures were evaluated in a group of 44 patients, and 16 measures in a group of 56 patients (three measures were evaluated in both groups). All the tests were performed at baseline and after 8 weeks treatment. A global impression of improvement (improved or not improved) scored by the patient was used as the standard for assessing the course of the disease. Responsiveness was examined by calculating the standardized response mean of the improved patients and by using a two-tailed Mann-Whitney nonparametric test to compare the patients who had improved and those who had not improved. RESULTS: Of the 48 effect measures, 26 measures of five categories (activities of daily living, pain, hip muscle strength, spine mobility, and spine muscle strength) showed good correlation with the patient's global impression of improvement. The measures in the "mobility of the pelvic joints" category were insufficient for assessing clinical change in posterior pelvic pain since pregnancy. The measures in the "fatigue" and "pain provocation tests" categories correlated only moderately with clinical change. CONCLUSIONS: It seems possible to gain appropriate information about the course of posterior pelvic pain since pregnancy with a small test battery. The usefulness of the Québec Back Pain Disability Scale, the hip adduction strength assessment, and the active straight-leg-raise test was proved by the current study. The value of 23 other instruments was substantiated, but further studies are needed to confirm their usefulness. The correlation of 22 evaluated measures with the patient's global improvement was too weak for them to be recommended as measures of clinical changes over time in posterior pelvic pain since pregnancy. It is recommended that clinicians and investigators compile a small test battery by selecting the best representatives of the five measurement categories that have good correlation with the patient's global impression of improvement.