Arthrokinematics in a subgroup of patients likely to benefit from a lumbar stabilization exercise program

Effect of verbal instructions on trunk muscle activity during volitional preemptive abdominal contraction

OBJECTIVE

This study investigated the effect of Verbal Instruction (VI) strategies on trunk muscle contraction among healthy subjects. The effect of three VI Abdominal Drawing-In Maneuver (ADIM) and two VI Abdominal Bracing Maneuver (ABM) strategies on left Internal (LIO) and External Oblique (LEO) and bilateral superficial Multifidi (sMf) activation was examined.

DESIGN

Within-subjects, repeated measure design.

METHODS

Surface EMG (sEMG) measured LIO, LEO, and sMf activity in 28 subjects (mean age 23.5 ± 5.5 years). Testing included five supine hook-lying and five quiet standing conditions.

RESULTS

One-way ANOVAs demonstrated no significant main effect for ADIM or ABM in supine or standing (p > .05). Muscle activation amplitudes during VPAC conditions demonstrated higher mean values for standing versus supine (p < .05) except for two conditions involving LEO. Friedman Tests for dominant strategy demonstrated a significant main effect for ADIM-VI and ABM-VI strategies. Post-hoc testing generally showed the dominant strategy to be significantly higher versus others.

CONCLUSION

No single preferred VI cue for ADIM or ABM was observed. Each subject's dominant strategy dictated the most suitable VI. Standing was preferred for LIO and sMf activation, whereas position did not change LEO activation. Non-significant correlations between all muscle pairings during all ADIM and ABM strategies were observed. These findings may suggest the need for healthcare providers who understand the intricacies of trunk stability to teach and monitor VPAC with either ADIM or ABM options.

The relationship between clinical examination measures and ultrasound measures of fascia thickness surrounding trunk muscles or lumbar multifidus fatty infiltrations: An exploratory study

Patients with chronic low back pain (CLBP) exhibit remodelling of the lumbar soft tissues such as muscle fatty infiltrations (MFI) and fibrosis of the lumbar multifidus (LuM) muscles, thickness changes of the thoracolumbar fascia (TLF) and perimuscular connective tissues (PMCT) surrounding the abdominal lateral wall muscles. Rehabilitative ultrasound imaging (RUSI) parameters such as thickness and echogenicity are sensitive to this remodelling. This experimental laboratory study aimed to explore whether these RUSI parameters (LuM echogenicity and fascia thicknesses), hereafter called dependent variables (DV) were linked to independent variables (IV) such as (1) other RUSI parameters (trunk muscle thickness and activation) and (2) physical and psychological measures. RUSI measures, as well as a clinical examination comprising physical tests and psychological questionnaires, were collected from 70 participants with LBP. The following RUSI dependent variables (RUSI-DV), measures of passive tissues were performed bilaterally: (1) LuM echogenicity (MFI/fibrosis) at three vertebral levels (L3/L4, L4/L5 and L5/S1); (2) TLF posterior layer thickness, and (3) PMCT thickness of the fasciae between subcutaneous tissue thickness (STT) and external oblique (PMCT_STT/EO ), between external and internal oblique (PMCT_EO/IO ), between IO and transversus abdominis (PMCT_IO/TrA ) and between TrA and intra-abdominal content (PMCT_TrA/IA ). RUSI measures of trunk muscle's function (thickness and activation), also called measures of active muscle tissues, were considered as independent variables (RUSI-IV), along with physical tests related to lumbar stability (n = 6), motor control deficits (n = 7), trunk muscle endurance (n = 4), physical performance (n = 4), lumbar posture (n = 2), and range of motion (ROM) tests (n = 6). Psychosocial measures included pain catastrophizing, fear-avoidance beliefs, psychological distress, illness perceptions and concepts related to adherence to a home-based exercise programme (physical activity level, self-efficacy, social support, outcome expectations). Six multivariate regression models (forward stepwise selection) were generated, using RUSI-DV measures as dependent variables and RUSI-IV/physical/psychosocial measures as independent variables (predictors). The six multivariate models included three to five predictors, explaining 63% of total LuM echogenicity variance, between 41% and 46% of trunk superficial fasciae variance (TLF, PMCT_STT/EO ) and between 28% and 37% of deeper abdominal wall fasciae variance (PMCT_EO/IO , PMCT_IO/TrA and PMCT_TrA/IA ). These variables were from RUSI-IV (LuM thickness at rest, activation of IO and TrA), body composition (percent fat) and clinical physical examination (lumbar and pelvis flexion ROM, aberrant movements, passive and active straight-leg raise, loaded-reach test) from the biological domain, as well as from the lifestyle (physical activity level during sports), psychological (psychological distress-cognitive subscale, fear-avoidance beliefs during physical activities, self-efficacy to exercise) and social (family support to exercise) domains. Biological, psychological, social and lifestyle factors each accounted for substantial variance in RUSI-passive parameters. These findings are in keeping with a conceptual link between tissue remodelling and factors such as local and systemic inflammation. Possible explanations are discussed, in keeping with the hypothesis-generating nature of this study (exploratory). However, to impact clinical practice, further research is needed to determine if the most plausible predictors of trunk fasciae thickness and LuM fatty infiltrations have an effect on these parameters.

Effects of ankle joint proprioceptive training and thermal approach on stroke patients' trunk, balance stability and gait parameter

BACKGROUND

Numerous studies have investigated factors for trunk, balance stability and gait parameters of post-stroke patients. Evidence-based recommendations are required for the treatment of ankle proprioceptive exercise with thermal stimulation in post-stroke patients.

OBJECTIVE

We investigated the effects of ankle proprioceptive exercise with thermal stimulation on the trunk stability, balance, and gait ability of post-stroke patients.

METHODS

A total of 30 patients were randomly divided into the ankle proprioceptive training and thermal stimulation group (APT) and control group. The APT group performed ankle proprioceptive exercises with thermal stimulation for 60 min five times a week for eight weeks. The control group followed conservative treatment for 60 min five times a week for eight weeks. Trunk stability was measured with the trunk impairment scale (TIS) and balance tests were performed with the center of pressure (COP), limits of stability (LOS), Berg Balance Scale (BBS), and functional reach test (FRT) and gait ability was performed by OptoGait and 10 m WT.

RESULTS

There was a significant difference (p< 0.05) between before and after training in both groups. The APT group showed significant improvement in both groups.

CONCLUSION

This study can be used as intervention data for recovering trunk, balance stability and gait parameters in post-stroke patients.

Whole-Body Reactive Agility Metrics to Identify Football Players With a Core and Lower Extremity Injury Risk

Clinical prediction models are useful in addressing several orthopedic conditions with various cohorts. American football provides a good population for attempting to predict injuries due to their relatively high injury rate. Physical performance can be assessed a variety of ways using an assortment of different tests to assess a diverse set of metrics, which may include reaction time, speed, acceleration, and deceleration. Asymmetry, the difference between right and left performance has been identified as a possible risk factor for injury. The purpose of this study was to determine the whole-body reactive agility metrics that would identify Division I football players who were at elevated risk for core, and lower extremity injuries (CLEI). This cohort study utilized 177 Division I football players with a total of 57 CLEI suffered who were baseline tested prior to the season. Single-task and dual-task whole-body reactive agility movements in lateral and diagonal direction reacting to virtual reality targets were analyzed separately. Receiver operator characteristic (ROC) analyses narrowed the 34 original predictor variables to five variables. Logistic regression analysis determined the three strongest predictors of CLEI for this cohort to be: lateral agility acceleration asymmetry, lateral flanker deceleration asymmetry, and diagonal agility reaction time average. Univariable analysis found odds ratios to range from 1.98 to 2.75 for these predictors of CLEI. ROC analysis had an area under the curve of 0.702 for any combination of two or more risk factors produced an odds ratio of 5.5 for risk of CLEI. These results suggest an asymmetry of 8-15% on two of the identified metrics or a slowed reaction time of ≥0.787 s places someone at increased risk of injury. Sixty-three percent (36/57) of the players who sustained an injury had ≥2 positive predictors In spite of the recognized limitation, these finding support the belief that whole-body reactive agility performance can identify Division I football players who are at elevated risk for CLEI.

Lumbar Intervertebral Kinematics During an Unstable Sitting Task and Its Association With Standing-Induced Low Back Pain

People developing transient low back pain during standing have altered control of their spine and hips during standing tasks, but the transfer of these responses to other tasks has not been assessed. This study used video fluoroscopy to assess lumbar spine intervertebral kinematics of people who do and do not develop standing-induced low back pain during a seated chair-tilting task. A total of 9 females and 8 males were categorized as pain developers (5 females and 3 males) or nonpain developers (4 females and 5 males) using a 2-hour standing exposure; pain developers reported transient low back pain and nonpain developers did not. Participants were imaged with sagittal plane fluoroscopy at 25 Hz while cyclically tilting their pelvises anteriorly and posteriorly on an unstable chair. Intervertebral angles, relative contributions, and anterior-posterior translations were measured for the L3/L4, L4/L5, and L5/S1 joints and compared between sexes, pain groups, joints, and tilting directions. Female pain developers experienced more extension in their L5/S1 joints in both tilting directions compared with female nonpain developers, a finding not present in males. The specificity in intervertebral kinematics to sex-pain group combinations suggests that these subgroups of pain developers and nonpain developers may implement different control strategies.

Intersegmental kinematic analysis of lumbar spine by functional radiography between two subgroups of patients with chronic low back pain

INTRODUCTION

Kinematic deficits such as fault in joint accessory motion is one of the most important contributing factors for developing the movement impairment in the lumbar spine. Functional radiography is accessible method for detecting the artherokinematic disorders. The aim of this study was to compare lumbar spine intersegmental motion between low back pain (LBP) subgroups of movement system impairment (MSI) model by functional radiography.

MATERIALS AND METHODS

20 subjects with chronic LBP in two subgroups of the MSI model (Rotation with Flexion and Rotation with Extension) participated in this study. Five x-rays were taken in different positions. Intersegmental linear translation and angular rotation of the lumbar segments were calculated.

RESULTS

In the Rotation with Extension subgroup, the translation and rotation values of the L3-4 segment from full to full position were significantly more than their values in the Rotation with Flexion subgroup ((mean difference = -1.69 (mm) P = 0.01), (mean difference = -3.80 (mm) P = 0.02) respectively). The translation of L2-3 segment from the neutral to the mid-flexion position was significantly greater in the Rotation with Flexion subgroup compared to the Rotation with Extension subgroup (mean difference = 1.12 (mm) P = 0.04). cumulative intersegmental angular rotation of all lumbar segments from mid to mid position was greater in the Rotation with Flexion subgroup compared to the Rotation with Extension subgroup (P = 0.03).

CONCLUSION

Changes in intersegmental translation and angular rotation of lumbar segments in subgroups of patients with LBP may be important contributing factors that induce direction specific lumbar spine loads and contribute to the development or persistence of LBP problems.

Identification of Risk Factors Prospectively Associated With Musculoskeletal Injury in a Warrior Athlete Population

BACKGROUND

Musculoskeletal injuries are a primary source of disability. Understanding how risk factors predict injury is necessary to individualize and enhance injury reduction programs.

HYPOTHESIS

Because of the multifactorial nature of musculoskeletal injuries, multiple risk factors will provide a useful method of categorizing warrior athletes based on injury risk.

STUDY DESIGN

Prospective observational cohort study.

LEVEL OF EVIDENCE

Level 2.

METHODS

Baseline data were collected on 922 US Army soldiers/warrior athletes (mean age, 24.7 ± 5.2 years; mean body mass index, 26.8 ± 3.4 kg/m²) using surveys and physical measures. Injury occurrence and health care utilization were collected for 1 year. Variables were compared in healthy versus injured participants using independent t tests or chi-square analysis. Significantly different factors between each group were entered into a logistic regression equation. Receiver operating characteristic curve and accuracy statistics were calculated for regression variables.

RESULTS

Of the 922 warrior athletes, 38.8% suffered a time-loss injury (TLI). Overall, 35 variables had a significant relationship with TLIs. The logistic regression equation, consisting of 11 variables of interest, was significant (adjusted R² = 0.21; odds ratio, 5.7 [95% CI, 4.1-7.9]; relative risk, 2.5 [95% CI, 2.1-2.9]; area under the curve, 0.73). Individuals with 2 variables had a sensitivity of 0.89, those with 7 or more variables had a specificity of 0.94.

CONCLUSION

The sum of individual risk factors (prior injury, prior work restrictions, lower perceived recovery from injury, asymmetrical ankle dorsiflexion, decreased or asymmetrical performance on the Lower and Upper Quarter Y-Balance test, pain with movement, slower 2-mile run times, age, and sex) produced a highly sensitive and specific multivariate model for TLI in military servicemembers.

CLINICAL RELEVANCE

A better understanding of characteristics associated with future injury risk can provide a foundation for prevention programs designed to reduce medical costs and time lost.

Comparison of intra subject repeatability of quantitative fluoroscopy and static radiography in the measurement of lumbar intervertebral flexion translation

Low back pain patients are sometimes offered fusion surgery if intervertebral translation, measured from static, end of range radiographs exceeds 3 mm. However, it is essential to know the measurement error of such methods, if selection for back surgery is going to be informed by them. Fifty-five healthy male (34) and female (21) pain free participants aged 21-80 years received quantitative fluoroscopic (QF) imaging both actively during standing and passively in the lateral decubitus position. The following five imaging protocols were extracted from 2 motion examinations, which were repeated 6 weeks apart: 1. Static during upright free bending. 2. Maximum during controlled upright bending, 3. At the end of controlled upright bending, 4. Maximum during controlled recumbent bending, 5. At the end of controlled recumbent bending. Intervertebral flexion translations from L2-S1 were determined for each protocol and their measurement errors (intra subject repeatability) calculated. Estimations using static, free bending radiographic images gave measurement errors of up to 4 mm, which was approximately twice that of the QF protocols. Significantly higher ranges at L4-5 and L5-S1 were obtained from the static protocol compared with the QF protocols. Weight bearing ranges at these levels were also significantly higher in males regardless of the protocol. Clinical decisions based on sagittal translations of less than 4 mm would therefore require QF imaging.

Analysis of Motor Control in Patients With Low Back Pain: A Key to Personalized Care?

SYNOPSIS

Motor control exercise has been shown to be effective in the management of low back pain (LBP). However, the effect sizes for motor control exercise are modest, possibly because studies have used a one-size-fits-all approach, while the literature suggests that patients may differ in presence or type of motor control issues. In this commentary, we address the question of whether consideration of such variation in motor control issues might contribute to more personalized motor control exercise for patients with LBP. Such an approach is plausible, because motor control changes may play a role in persistence of pain through effects on tissue loading that may cause nociceptive afference, particularly in the case of peripheral sensitization. Subgrouping systems used in clinical practice, which comprise motor control aspects, allow reliable classification that is, in part, aligned with findings in studies on motor control in patients with LBP. Motor control issues may have heuristic value for treatment allocation, as the different presentations observed suggest different targets for motor control exercise, but this remains to be proven. Finally, clinical assessment of patients with LBP should take into account more aspects than motor control alone, including pain mechanisms, musculoskeletal health, and psychosocial factors, and may need to be embedded in a stratification approach based on prognosis to avoid undue diagnostic procedures. J Orthop Sports Phys Ther 2019;49(6):380-388. Epub 12 Jun 2018. doi:10.2519/jospt.2019.7916.

Clinical spinal instability: 10 years since the derivation of a clinical prediction rule. A narrative literature review

BACKGROUND

Between 2005 and 2015 significant changes in the clinical decision making paradigm for the treatment of spinal instability occurred. This was largely motivated by a clinical prediction rule (CPR) derivation study that was developed to specifically identify patients with low back pain who are more likely to respond positively to lumbar stabilization exercises.

OBJECTIVE

This is a narrative literature review on the recent advances physiotherapy has made in the treatment of clinical spinal instability.

METHODS

Literature discussing the conservative treatment of lumbar spinal instability published from 2005-2015 was identified with electronic searches of PubMed (MEDLINE) Advanced search, Web of Science, BIOSIS Previews, MEDLINE (EBSCO), SportDISCUS (EBSCO), CINAHL (EBSCO), PEDro, Scopus and Cochrane and reviewed.

RESULTS

Five systematic reviews, 2 with meta-analyses, and 1 systematic review on the quality of systematic reviews were found. There seems to be some benefit from specific stabilization exercise programs in regards to pain reduction, but they might not be more effective than other forms of exercise. The currently existing CPR for stabilization exercises is not far enough developed to use in clinical practice and is not validated as of yet.

CONCLUSION

Stabilization exercises seem to decrease chronic low back pain, although it is not clear that this pain has to be caused by clinical spinal instability. Caution should be exercised when using CPRs in the clinic; they are not meant to be strict treatment guidelines, but rather a tool that helps facilitate clinical decision-making.

Intrasubject repeatability of in vivo intervertebral motion parameters using quantitative fluoroscopy

PURPOSE

In vivo quantification of intervertebral motion through imaging has progressed to a point where biomarkers for low back pain are emerging. This makes possible deeper study of the condition's biometrics. However, the measurement of change over time involves error. The purpose of this prospective investigation is to determine the intrasubject repeatability of six in vivo intervertebral motion parameters using quantitative fluoroscopy.

METHODS

Intrasubject reliability (ICC) and minimal detectable change (MDC) of baseline to 6-week follow-up measurements were calculated for six lumbar spine intervertebral motion parameters in 109 healthy volunteers. A standardised quantitative fluoroscopy (QF) protocol was used to provide measurements in the coronal and sagittal planes using both passive recumbent and active weight-bearing motion. Parameters were: intervertebral range of motion (IV-RoM), laxity, motion sharing inequality (MSI), motion sharing variability (MSV), flexion translation and anterior disc height change during flexion.

RESULTS

The best overall intrasubject reliability (ICC) and agreement (MDC) were for disc height (ICC 0.89, MDC 43%) and IV-RoM (ICC 0.96, MDC 60%), and the worst for MSV (ICC 0.04, MDC 408%). Laxity, MSI and translation had acceptable reliability (most ICCs > 0.60), but not agreement (MDC > 85%).

CONCLUSION

Disc height and IV-RoM measurement using QF could be considered for randomised trials, while laxity, MSI and translation could be considered for moderators, correlates or mediators of patient-reported outcomes. MSV had both poor reliability and agreement over 6 weeks. These slides can be retrieved under Electronic Supplementary Material.

Predictors of clinical success with stabilization exercise are associated with lower levels of lumbar multifidus intramuscular adipose tissue in patients with low back pain

Purpose: Investigate the construct validity of prognostic factors purported to predict clinical success with stabilization exercise for low back pain by exploring their associations with lumbar multifidus composition.Methods: Patients with low back pain were recruited from a hospital imaging department. The presence of fivepredictors (age <40 years, positive prone instability test, aberrant trunk flexion movements, straight leg raise range of motion >91°, spinal hypermobility) were identified by standardized physical examination. Predictors were grouped by total positive findings and status on a clinical prediction rule. The proportion of lower lumbar multifidus intramuscular adipose tissue was measured with 3.0 T magnetic resonance imaging. Univariate and multivariate associations were examined with linear regression and reported with standardized beta coefficients (β) and 95% confidence intervals.Results: Data from 62 patients (11 female) with mean (SD) age of 45.2 (11.8) years were included. Total number of predictors (β[95% CI] = -0.37[-0.61,-0.12]; R² = 0.12), positive prediction rule status (β[95% CI] = -0.57[-0.79,-0.35]; R² = 0.30), and age <40 years were associated with lower intramuscular adipose tissue (β[95% CI] = -0.55[-0.77,-0.33]; R² = 0.27). No other individual factors were associated with lumbar multifidus intramuscular adipose tissue.Conclusions: These findings support the construct validity of the grouped prognostic criteria. Future research should examine the clinical utility of these criteria. Implications for RehabilitationLow back pain is the single largest cause of disability worldwide and exercise therapy is recommended by international low back pain treatment guidelines.Lower levels of lumbar multifidus intramuscular adipose tissue were associated with predictors of clinical success with stabilization exercise.Higher proportions of lumbar multifidus intramuscular adipose tissue may help identify patients who require longer duration exercise training, or those who are unlikely to respond to stabilization exercise.

Uneven intervertebral motion sharing is related to disc degeneration and is greater in patients with chronic, non-specific low back pain: an in vivo, cross-sectional cohort comparison of intervertebral dynamics using quantitative fluoroscopy

PURPOSE

Evidence of intervertebral mechanical markers in chronic, non-specific low back pain (CNSLBP) is lacking. This research used dynamic fluoroscopic studies to compare intervertebral angular motion sharing inequality and variability (MSI and MSV) during continuous lumbar motion in CNSLBP patients and controls. Passive recumbent and active standing protocols were used and the relationships of these variables to age and disc degeneration were assessed.

METHODS

Twenty patients with CNSLBP and 20 matched controls received quantitative fluoroscopic lumbar spine examinations using a standardised protocol for data collection and image analysis. Composite disc degeneration (CDD) scores comprising the sum of Kellgren and Lawrence grades from L2-S1 were obtained. Indices of intervertebral motion sharing inequality (MSI) and variability (MSV) were derived and expressed in units of proportion of lumbar range of motion from outward and return motion sequences during lying (passive) and standing (active) lumbar bending and compared between patients and controls. Relationships between MSI, MSV, age and CDD were assessed by linear correlation.

RESULTS

MSI was significantly greater in the patients throughout the intervertebral motion sequences of recumbent flexion (0.29 vs. 0.22, p = 0.02) and when flexion, extension, left and right motion were combined to give a composite measure (1.40 vs. 0.92, p = 0.04). MSI correlated substantially with age (R = 0.85, p = 0.004) and CDD (R = 0.70, p = 0.03) in lying passive investigations in patients and not in controls. There were also substantial correlations between MSV and age (R = 0.77, p = 0.01) and CDD (R = 0.85, p = 0.004) in standing flexion in patients and not in controls.

CONCLUSION

Greater inequality and variability of motion sharing was found in patients with CNSLBP than in controls, confirming previous studies and suggesting a biomechanical marker for the disorder at intervertebral level. The relationship between disc degeneration and MSI was augmented in patients, but not in controls during passive motion and similarly for MSV during active motion, suggesting links between in vivo disc mechanics and pain generation.

The Effect of Current Low Back Pain on Volitional Preemptive Abdominal Activation During a Loaded Forward Reach Activity

BACKGROUND

A volitional preemptive abdominal contraction (VPAC) supports trunk stability during functional activity. Pain-free individuals can sustain VPAC during function, but such has not been reported for individuals with current low back pain (cLBP).

OBJECTIVE

To examine whether cLBP affects VPAC performance during a loaded forward reach (LFR) task.

DESIGN

Observational crossover study.

SETTING

Laboratory.

PARTICIPANTS

A total of 18 controls and 17 subjects with cLBP with pain ratings of 1/10 to 4/10 on a visual analog scale.

INTERVENTIONS

Transverse abdominis (TrA) thickness measurements were recorded by blinded researchers from M-mode ultrasound imaging during 4 conditions: (1) quiet standing without abdominal drawing-in maneuver (ADIM); (2) quiet standing with ADIM; (3) LFR without ADIM; and (4) LFR with ADIM. A physical therapist with 29 years of experience collected historical and examination data.

MAIN OUTCOME MEASURES

TrA muscle thickness (mm).

RESULTS

A 2 (group) × 2 (contraction) × 2 (reach) analysis of variance demonstrated a significant group × contraction interaction (F [1, 31] = 4.499, P = .04) where ADIM produced greater TrA thickness increases in PLBP subjects (2.18 mm) versus controls (1.36 mm). We observed a significant main effect for reach (F [1, 31] = 14.989, P < .001), where LFR activity produced a greater TrA thickness (6.15 ± 2.48 mm) versus quiet standing (5.30 ± 2.12 mm).

CONCLUSIONS

Subjects with cLBP demonstrated a greater increase in TrA activation during ADIM versus controls.

Relationships between Paraspinal Muscle Activity and Lumbar Inter-Vertebral Range of Motion

Control of the lumbar spine requires contributions from both the active and passive sub-systems. Identifying interactions between these systems may provide insight into the mechanisms of low back pain. However, as a first step it is important to investigate what is normal. The purpose of this study was to explore the relationships between the lumbar inter-vertebral range of motion and paraspinal muscle activity during weight-bearing flexion in healthy controls using quantitative fluoroscopy (QF) and surface electromyography (sEMG). Contemporaneous lumbar sEMG and QF motion sequences were recorded during controlled active flexion of 60° using electrodes placed over Longissimus thoracis pars thoracis (TES), Longissimus thoracis pars lumborum (LES), and Multifidus (LMU). Normalised root mean square (RMS) sEMG amplitude data were averaged over five epochs, and the change in amplitude between epochs was calculated. The sEMG ratios of LMU/LES LMU/TES and LES/TES were also determined. QF was used to measure the maximum inter-vertebral range of motion from L2-S1, and correlation coefficients were calculated between sEMG amplitude variables and these measurements. Intra- and inter-session sEMG amplitude repeatability was also assessed for all three paraspinal muscles. The sEMG amplitude measurements were highly repeatable, and sEMG amplitude changes correlated significantly with L4-5 and L5-S1 IV-RoMmax (r = -0.47 to 0.59). The sEMG amplitude ratio of LES/TES also correlated with L4-L5 IV-RoMmax (r = -0.53). The relationships found may be important when considering rehabilitation for low back pain.

What Risk Factors Are Associated With Musculoskeletal Injury in US Army Rangers? A Prospective Prognostic Study

BACKGROUND

Musculoskeletal injury is the most common reason that soldiers are medically not ready to deploy. Understanding intrinsic risk factors that may place an elite soldier at risk of musculoskeletal injury may be beneficial in preventing musculoskeletal injury and maintaining operational military readiness. Findings from this population may also be useful as hypothesis-generating work for particular civilian settings such as law enforcement officers (SWAT teams), firefighters (smoke jumpers), or others in physically demanding professions.

QUESTIONS/PURPOSES

The purposes of this study were (1) to examine whether using baseline measures of self-report and physical performance can identify musculoskeletal injury risk; and (2) to determine whether a combination of predictors would enhance the accuracy for determining future musculoskeletal injury risk in US Army Rangers.

METHODS

Our study was a planned secondary analysis from a prospective cohort examining how baseline factors predict musculoskeletal injury. Baseline predictors associated with musculoskeletal injury were collected using surveys and physical performance measures. Survey data included demographic variables, injury history, and biopsychosocial questions. Physical performance measures included ankle dorsiflexion, Functional Movement Screen, lower and upper quarter Y-balance test, hop testing, pain provocation, and the Army Physical Fitness Test (consisting of a 2-mile run and 2 minutes of sit-ups and push-ups). A total of 320 Rangers were invited to enroll and 211 participated (66%). Occurrence of musculoskeletal injury was tracked for 1 year using monthly injury surveillance surveys, medical record reviews, and a query of the Department of Defense healthcare utilization database. Injury surveillance data were available on 100% of the subjects. Receiver operator characteristic curves and accuracy statistics were calculated to identify predictors of interest. A logistic regression equation was then calculated to find the most pertinent set of predictors. Of the 188 Rangers (age, 23.3 ± 3.7 years; body mass index, 26.0 ± 2.4 kg/m(2)) remaining in the cohort, 85 (45.2%) sustained a musculoskeletal injury of interest.

RESULTS

Smoking, prior surgery, recurrent prior musculoskeletal injury, limited-duty days in the prior year for musculoskeletal injury, asymmetrical ankle dorsiflexion, pain with Functional Movement Screen clearing tests, and decreased performance on the 2-mile run and 2-minute sit-up test were associated with increased injury risk. Presenting with one or fewer predictors resulted in a sensitivity of 0.90 (95% confidence interval [CI], 0.83-0.95), and having three or more predictors resulted in a specificity of 0.98 (95% CI, 0.93-0.99). The combined factors that contribute to the final multivariable logistic regression equation yielded an odds ratio of 4.3 (95% CI, 2.0-9.2), relative risk of 1.9 (95% CI, 1.4-2.6), and an area under the curve of 0.64.

CONCLUSIONS

Multiple factors (musculoskeletal injury history, smoking, pain provocation, movement tests, and lower scores on physical performance measures) were associated with individuals at risk for musculoskeletal injury. The summation of the number of risk factors produced a highly sensitive (one or less factor) and specific (three or more factors) model that could potentially be used to effectively identify and intervene in those persons with elevated risk for musculoskeletal injury. Future research should establish if screening and intervening can improve musculoskeletal health and if our findings among US Army Rangers translate to other occupations or athletes.

LEVEL OF EVIDENCE

Level II, prognostic study.

Measurement Performance of a Computer Assisted Vertebral Motion Analysis System

BACKGROUND

Segmental instability of the lumbar spine is a significant cost within the US health care system; however current thresholds for indication of radiographic instability are not well defined.

PURPOSE

To determine the performance measurements of sagittal lumbar intervertebral measurements using computerassisted measurements of the lumbar spine using motion sequences from a video-fluoroscopic technique.

STUDY DESIGN

Sensitivity, specificity, predictive values, prevalence, and test-retest reliability evaluation of digitized manual versus computer-assisted measurements of the lumbar spine.

PATIENT SAMPLE

A total of 2239 intervertebral levels from 509 symptomatic patients, and 287 intervertebral levels from 73 asymptomatic participants were retrospectively evaluated.

OUTCOME MEASURES

Specificity, sensitivity, negative predictive value (NPV), diagnostic accuracy, and prevalence between the two measurement techniques; Measurements of Coefficient of repeatability (CR), limits of agreement (LOA), intraclass correlation coefficient (ICC; type 3,1), and standard error of measurement for both measurement techniques.

METHODS

Asymptomatic individuals and symptomatic patients were all evaluated using both the Vertebral Motion Analysis (VMA) system and fluoroscopic flexion extension static radiographs (FE). The analysis was compared to known thresholds of 15% intervertebral translation (IVT, equivalent to 5.3mm assuming a 35mm vertebral body depth) and 25° intervertebral rotation (IVR).

RESULTS

The VMA measurements demonstrated greater specificity, % change in sensitivity, NPV, prevalence, and reliability compared with FE for radiographic evidence of instability. Specificity was 99.4% and 99.1% in the VMA compared to 98.3% and 98.2% in the FE for IVR and IVT, respectively. Sensitivity in this study was 41.2% and 44.6% greater in the VMA compared to the FE for IVR and IVT, respectively. NPV was 91% and 88% in the VMA compared to 62% and 66% in the FE for IVR and IVT, respectively. Prevalence was 12.3% and 11.9% for the VMA compared to 6.1% and 5.4% for the FE in IVR and IVT, respectively. Intra-observer IVR and IVT had a CR of 2.49 and 2.62, respectively. Inter-observer IVR and IVT had a CR of 1.99 and 2.81, respectively. Intra-subject (test/retest) CR were 2.49 and 3.11 for IVR and IVT, respectively.

CONCLUSIONS

The VMA system showed greater measurement performance in the detection of radiographic instability compared with FE radiographs.

An exploratory examination of the association between altered lumbar motor control, joint mobility and low back pain in athletes

Background:

Low back pain (LBP) is a common cause of lost playing time and can be a challenging clinical condition in competitive athletes. LBP in athletes may be associated with joint and ligamentous hypermobility and impairments in activation and coordination of the trunk musculature, however there is limited research in this area.

Objectives:

To determine if there is an association between altered lumbar motor control, joint mobility and low back pain (LBP) in a sample of athletes.

Materials and Methods:

Fifteen athletes with LBP were matched by age, gender and body mass index (BMI) with controls without LBP. Athletes completed a questionnaire with questions pertaining to demographics, activity level, medical history, need to self-manipulate their spine, pain intensity and location. Flexibility and lumbar motor control were assessed using: active and passive straight leg raise, lumbar range of motion (ROM), hip internal rotation ROM (HIR), Beighton ligamentous laxity scale, prone instability test (PIT), observation of lumbar aberrant movements, double leg lowering and Trendelenburg tests. Descriptive statistics were compiled and the chi square test was used to analyze results.

Results:

Descriptive statistics showed that 40% of athletes with LBP exhibited aberrant movements (AM), compared to 6% without LBP. 66% of athletes with LBP reported frequently self-manipulating their spine compared to 40% without LBP. No significant differences in motor control tests were found between groups. Athletes with LBP tended to have less lumbar flexion (63 ± 11°) compared to those without LBP (66 ± 13°). Chi-Square tests revealed that the AM were more likely to be present in athletes with LBP than those without (X2 = 4.66, P = 0.03).

Conclusions:

The presence of aberrant movement patterns is a significant clinical finding and associated with LBP in athletes.

Effects of selective exercise for the deep abdominal muscles and lumbar stabilization exercise on the thickness of the transversus abdominis and postural maintenance

[Purpose] The purpose of this study was to examine the effects of selective exercise for the deep abdominal muscles (SEDA) and lumbar stabilization exercise (LSE) on the thickness of the transversus abdominis and postural maintenance on an unstable base of support. [Subjects and Methods] The subjects of this study were 20 male and 10 female adults in their 20s without lumbar pain. They were equally and randomly assigned to a SEDA group and a LSE group. The thickness of the transversus abdominis was measured using ultrasound imaging during rest and drawing-in. The thickness of the transversus abdominis was measured when subjects raised their right and left legs while lying on a Swiss ball. [Results] Initially, there were no differences between the two groups. After the intervention, significant differences were observed in all parameters. A significant interaction between group and period was not found for any parameters. [Conclusion] In conclusion, both SEDA and LSE thickened the transversus abdominis, which is a deep abdominal muscle, thereby adjusting posture, and stabilizing the trunk. These exercises increased the thickness of the deep abdominal muscles. They are important exercises for improving the stability of athletes or patients who need postural adjustment.

Validation and impact analysis of prognostic clinical prediction rules for low back pain is needed: a systematic review

OBJECTIVES

To identify prognostic forms of clinical prediction rules (CPRs) related to the nonsurgical management of adults with low back pain (LBP) and to evaluate their current stage of development.

STUDY DESIGN AND SETTING

Systematic review using a sensitive search strategy across seven databases with hand searching and citation tracking.

RESULTS

A total of 10,005 records were screened for eligibility with 35 studies included in the review. The included studies report on the development of 30 prognostic LBP CPRs. Most of the identified CPRs are in their initial phase of development. Three CPRs were found to have undergone validation--the Cassandra rule for predicting long-term significant functional limitations and the five-item and two-item Flynn manipulation CPRs for predicting a favorable functional prognosis in patients being treated with lumbopelvic manipulation. No studies were identified that investigated whether the implementation of a CPR resulted in beneficial patient outcomes or improved resource efficiencies.

CONCLUSION

Most of the identified prognostic CPRs for LBP are in the initial phase of development and are consequently not recommended for direct application in clinical practice at this time. The body of evidence provides emergent confidence in the limited predictive performance of the Cassandra rule and the five-item Flynn manipulation CPR in comparable clinical settings and patient populations.

Clinical observation of standing trunk movements: what do the aberrant movement patterns tell us?

STUDY DESIGN

Clinical measurement, cross-sectional study.

OBJECTIVE

To investigate the reliability of observation of aberrant movement patterns (altered lumbopelvic rhythm, deviation from sagittal plane, instability catch or judder, and painful arc of motion) and to determine whether each pattern is associated with current low back pain (LBP).

BACKGROUND

Identification of aberrant movement patterns during trunk motion is an important component of subclassifying patients with LBP and prescribing evidence-based interventions. However, reported reliability for observation of specific aberrant patterns is low, and observation of any aberrant pattern (clinical definition of positive test) has ranged from poor to moderate. In addition, the validity of the association of clinical observations of aberrant movements during forward bending with LBP or dysfunction has yet to be determined.

METHODS

Experienced physical therapists simultaneously observed trunk movements of 102 subjects with no LBP, current LBP, or history of LBP. Kappa statistics were used to evaluate interrater agreement in identifying different types of aberrant patterns. Associations were used to determine the validity of the hypothesized relationship between aberrant patterns and LBP.

RESULTS

Interrater reliability of identifying the different types of aberrant patterns in subjects with LBP ranged from fair (κ = 0.35; 95% confidence interval: 0.00, 0.71) to excellent (κ = 0.89; 95% confidence interval: 0.69, 1.00). Using the clinical definition of 1 observation of any aberrant motion, interrater agreement was substantial (κ = 0.65; 95% confidence interval: 0.00, 1.00). Significant association was found between judder, deviation, and LBP. The frequency of observed aberrant patterns was significantly associated with LBP.

CONCLUSION

Simultaneous observation for specific aberrant movement patterns suggests that identification can be performed with at least fair interrater agreement, and observation of any pattern with substantial agreement. Aberrant patterns are more frequently observed in patients with current complaints of LBP; however, they also appear in individuals with a history of LBP and no LBP.

Effect of recurrent low back pain history on volitional pre-emptive abdominal activation during a loaded functional reach activity

STUDY DESIGN

A 2 (group) × 2 (abdominal contraction) × 2 (reach activity) crossover mixed design with repeated measures for contraction and activity examined the effects of a loaded (4.6 kg) forward-reach activity and abdominal drawing-in maneuver (ADIM) on transversus abdominis (TrA) contraction in subjects with nonspecific low back pain (NSLBP) history versus controls.

OBJECTIVE

We measured TrA contraction during a loaded forward-reach activity while using the ADIM and examined if a NSLBP history affects TrA activity.

SUMMARY OF BACKGROUND DATA

The ADIM supports trunk stability during function. Clinicians incorporate ADIM during patients' functional tasks. Pain-free individuals can sustain ADIM during function, such as forward-reach. However, this has not been tested in those with a NSLBP history.

METHODS

Eighteen normal subjects and 18 subjects with a history of NSLBP participated. A blinded investigator recorded M-mode ultrasound imaging measurements of TrA thickness (mm) during 4 conditions as follows: (1) quiet standing without ADIM; (2) quiet standing with ADIM; (3) loaded forward-reach without ADIM; and (4) loaded forward-reach with ADIM.

RESULTS

A mixed analysis of variance demonstrated a significant main effect for group (F [1, 34] = 5.404, P = 0.026; ), where TrA thickness was greater for NSLBP history (7.41 + 2.34 mm) versus controls (5.9 + 2.46 mm). A significant main effect was observed for abdominal contraction (F [1, 34] = 49.57, P < 0.0001; ), where TrA thickness was greater during ADIM (7.47 + 2.7 mm) versus without ADIM (5.84, 1.92 m). A significant main effect was observed for forward-reach activity (F [1, 34] = 12.79, P = 0.001; ), where TrA thickness was greater during a loaded forward-reach (7.04 + 2.6 mm) versus quiet standing (6.2 + 2.4 mm). There were no significant interactions.

CONCLUSION

Individuals can use a volitional pre-emptive ADIM for trunk protection during loaded forward-reach, potentially reducing injury risk. A NSLBP history increases TrA activation during ADIM, suggesting an enhanced protective role.

LEVEL OF EVIDENCE

2.

A clinical prediction rule to identify patients with low back pain who are likely to experience short-term success following lumbar stabilization exercises: a randomized controlled validation study

STUDY DESIGN

Randomized controlled trial.

OBJECTIVE

To determine the validity of a previously suggested clinical prediction rule (CPR) for identifying patients most likely to experience short-term success following lumbar stabilization exercise (LSE). Background Although LSE is commonly used by physical therapists in the management of low back pain, it does not seem to be more effective than other interventions. A 4-item CPR for identifying patients most likely to benefit from LSE has been previously suggested but has yet to be validated.

METHODS

One hundred five patients with low back pain underwent a baseline examination to determine their status on the CPR (positive or negative). Patients were stratified by CPR status and then randomized to receive an LSE program or an intervention consisting of manual therapy (MT) and range-of-motion/flexibility exercises. Both interventions included 11 treatment sessions delivered over 8 weeks. Low back pain-related disability was measured by the modified version of the Oswestry Disability Index at baseline and upon completion of treatment.

RESULTS

The statistical significance for the 2-way interaction between treatment group and CPR status for the level of disability at the end of the intervention was P = .17. However, among patients receiving LSE, those with a positive CPR status experienced less disability by the end of treatment compared with those with a negative CPR status (P = .02). Also, among patients with a positive CPR status, those receiving LSE experienced less disability by the end of treatment compared with those receiving MT (P = .03). In addition, there were main effects for treatment and CPR status. Patients receiving LSE experienced less disability by the end of treatment compared to patients receiving MT (P = .05), and patients with a positive CPR status experienced less disability by the end of treatment compared to patients with a negative CPR status, regardless of the treatment received (P = .04). When a modified version of the CPR (mCPR) containing only the presence of aberrant movement and a positive prone instability test was used, a significant interaction with treatment was found for final disability (P = .02). Of the patients who received LSE, those with a positive mCPR status experienced less disability by the end of treatment compared to those with a negative mCPR status (P = .02), and among patients with a positive mCPR status, those who received LSE experienced less disability by the end of treatment compared to those who received MT (P = .005).

CONCLUSION

The previously suggested CPR for identifying patients likely to benefit from LSE could not be validated in this study. However, due to its relatively low level of power, this study could not invalidate the CPR, either. A modified version of the CPR that contains only 2 items may possess a better predictive validity to identify those most likely to succeed with an LSE program. Because this modified version was established through post hoc testing, an additional study is recommended to prospectively test its predictive validity.

LEVEL OF EVIDENCE

Prognosis, level 1b-.

Quality of systematic reviews on specific spinal stabilization exercise for chronic low back pain

STUDY DESIGN

Systematic literature review.

OBJECTIVE

To evaluate the quality of systematic reviews (SRs) on specific stabilization exercises for chronic low back pain (LBP).

BACKGROUND

Multiple SRs regarding the effectiveness of lumbar stabilization exercises for people with chronic LBP have been published. As more SRs are published, the more it is recognized that, like other forms of research, methodological quality affects the validity of, and conclusions drawn from, the data.

METHODS

A search of MEDLINE, CINAHL, and Embase was completed. Additionally, the PEDro database was screened and hand searching was completed. Included SRs had to contain randomized controlled trials examining a specific stabilization exercise program for the treatment of chronic LBP. Additionally, the assessed outcome measures had to include pain and/or disability measures. Literature reviews and clinical practice guidelines were excluded. Three reviewers independently assessed each SR for methodological quality.

RESULTS

The search produced 665 SRs for review, of which 8 fulfilled the inclusion criteria. Consensus quality assessment scores ranged from 13/26 to 26/26, with an average of 20.7 points. Percent agreement and kappa values for individual criteria scores ranged from 50% to 92% and 0.25 to 0.85, respectively. Agreement was moderate to substantial across individual items, except for criterion 1. The intraclass correlation coefficient for overall score was 0.98 (95% confidence interval: 0.96, 0.99).

CONCLUSION

This review of SRs identified several high-quality reviews that indicated some benefit of specific stabilization exercise programs for patients with nonspecific chronic LBP.

LEVEL OF EVIDENCE

Therapy, level 1a.

Subgrouping patients with low back pain: a treatment-based approach to classification

Context:

Low back pain (LBP) is a prevalent condition imposing a large socioeconomic burden. Despite intensive research aimed at the efficacy of various therapies for patients with LBP, most evidence has failed to identify a superior treatment approach. One proposed solution to this dilemma is to identify subgroups of patients with LBP and match them with targeted therapies. Among the subgrouping approaches, the system of treatment-based classification (TBC) is promoted as a means of increasing the effectiveness of conservative interventions for patients with LBP.

Evidence acquisition:

MEDLINE and PubMed databases were searched from 1985 through 2010, along with the references of selected articles.

Results:

TBC uses a standardized approach to categorize patients into 1 of 4 subgroups: spinal manipulation, stabilization exercise, end-range loading exercise, and traction. Although the TBC subgroups are in various stages of development, recent research lends support to the effectiveness of this approach.

Conclusions:

While additional research is required to better elucidate this method, the TBC approach enhances clinical decision making, as evidenced by the improved clinical outcomes experienced by patients with LBP.

Modifying patterns of movement in people with low back pain -does it help? A systematic review

BACKGROUND

Physiotherapy for people with low back pain frequently includes assessment and modification of lumbo-pelvic movement. Interventions commonly aim to restore normal movement and thereby reduce pain and improve activity limitation. The objective of this systematic review was to investigate: (i) the effect of movement-based interventions on movement patterns (muscle activation, lumbo-pelvic kinematics or postural patterns) of people with low back pain (LBP), and (ii) the relationship between changes in movement patterns and subsequent changes in pain and activity limitation.

METHODS

MEDLINE, Cochrane Central, EMBASE, AMI, CINAHL, Scopus, AMED, ISI Web of Science were searched from inception until January 2012. Randomised controlled trials or controlled clinical trials of people with LBP were eligible for inclusion. The intervention must have been designed to influence (i) muscle activity patterns, (ii) lumbo-pelvic kinematic patterns or (iii) postural patterns, and included measurement of such deficits before and after treatment, to allow determination of the success of the intervention on the lumbo-pelvic movement. Twelve trials (25% of retrieved studies) met the inclusion criteria. Two reviewers independently identified, assessed and extracted data. The PEDro scale was used to assess method quality. Intervention effects were described using standardised differences between group means and 95% confidence intervals.

RESULTS

The included trials showed inconsistent, mostly small to moderate intervention effects on targeted movement patterns. There was considerable heterogeneity in trial design, intervention type and outcome measures. A relationship between changes to movement patterns and improvements in pain or activity limitation was observed in one of six studies on muscle activation patterns, one of four studies that examined the flexion relaxation response pattern and in two of three studies that assessed lumbo-pelvic kinematics or postural characteristics.

CONCLUSIONS

Movement-based interventions were infrequently effective for changing observable movement patterns. A relationship between changes in movement patterns and improvement in pain or activity limitation was also infrequently observed. No independent studies confirm any observed relationships. Challenges for future research include defining best methods for measuring (i) movement aberrations, (ii) improvements in movements, and (iii) the relationship between changes in how people move and associated changes in other health indicators such as activity limitation.

Preliminary state of development of prediction models for primary care physical therapy: a systematic review

OBJECTIVE

To summarize the methodological quality and developmental stage of prediction models for musculoskeletal complaints that are relevant for physical therapists in primary care.

STUDY DESIGN AND SETTING

A systematic literature search was carried out in the databases of Medline, Embase, and Cinahl. Studies on prediction models for musculoskeletal complaints that can be used by primary care physical therapists were included. Methodological quality of the studies was assessed and relevant study characteristics were extracted.

RESULTS

The search retrieved 4,702 references of which 29 studies were included in this review. The study quality of the included studies showed substantial variation. The studied populations consisted mostly of back (n=10) and neck pain (n=6) patients, and patients with knee complaints (n=4). Most studies (n=22) used "perceived recovery" as primary outcome. Most prediction models (n=18) were at the derivation level of development.

CONCLUSIONS

Many prediction models are available for a wide range of patient populations. The developmental stage of most models is preliminary and the study quality is often moderate. We do not recommend physiotherapist to use these models yet. All models reviewed here are in the developmental stage and need validation and impact evaluation before using them in daily practice.

Measurement of intervertebral motion using quantitative fluoroscopy: report of an international forum and proposal for use in the assessment of degenerative disc disease in the lumbar spine

Quantitative fluoroscopy (QF) is an emerging technology for measuring intervertebral motion patterns to investigate problem back pain and degenerative disc disease. This International Forum was a networking event of three research groups (UK, US, Hong Kong), over three days in San Francisco in August 2009. Its aim was to reach a consensus on how best to record, analyse, and communicate QF information for research and clinical purposes. The Forum recommended that images should be acquired during regular trunk motion that is controlled for velocity and range, in order to minimise externally imposed variability as well as to correlate intervertebral motion with trunk motion. This should be done in both the recumbent passive and weight bearing active patient configurations. The main recommended outputs from QF were the true ranges of intervertebral rotation and translation, neutral zone laxity and the consistency of shape of the motion patterns. The main clinical research priority should initially be to investigate the possibility of mechanical subgroups of patients with chronic, nonspecific low back pain by comparing their intervertebral motion patterns with those of matched healthy controls.

Investigation of abdominal muscle thickness changes after spinal manipulation in patients who meet a clinical prediction rule for lumbar stabilization

STUDY DESIGN

Prospective case series.

OBJECTIVES

To investigate changes in abdominal muscle thickness with ultrasound imaging, after spinal manipulative therapy (SMT), in a subgroup of patients with low back pain (LBP) who meet a proposed clinical prediction rule for lumbar stabilization exercise (LSE).

BACKGROUND

The characteristics of a subgroup of patients with LBP who respond clinically to LSE has been proposed. Although the pathoanatomical characteristics of this subgroup have not been determined, clinicians often assume that this type of LBP is related, in part, to neuromuscular deficits of the lateral abdominal muscles. Recent evidence suggests that SMT may facilitate abdominal muscle activity and, therefore, enhance exercises targeting these deficits.

METHODS

Nineteen patients (mean age ± SD, 32.5 ± 7.8 years; 11 female) with LBP, who met the criteria for LSE, underwent ultrasound imaging of the transversus abdominis (TrA) and internal oblique (IO) muscles before, immediately after, and 3 to 4 days after lumbopelvic SMT. Measurements of resting thickness, contracted thickness during the abdominal drawing-in maneuver, and percent thickness change from rest to contraction of the TrA and IO muscles were analyzed with repeated-measures analysis of variance. Numeric pain rating scale and Oswestry Disability Index data were also collected.

RESULTS

No significant differences in resting, contracted, or percent thickness change in the TrA or IO were found over the 3 time periods. There were statistically significant reductions in numeric pain rating scale and Oswestry Disability Index scores, but mean differences failed to meet the minimal clinically important difference.

CONCLUSION

The results provide preliminary evidence that TrA and IO muscle resting and contracted thicknesses do not change post-SMT in patients with LBP in the LSE subgroup. In addition, while reductions in pain and disability were noted, they were not clinically meaningful.

Prescriptive clinical prediction rules in back pain research: a systematic review

Prescriptive clinical prediction rules (CPRs) are a way of using a small selection of clinical findings to match patients to optimal interventions. A number of CPRs have been developed for use with back pain patients, but these have not been systematically reviewed. The purpose of this review was to evaluate existing CPRs against established criteria to determine the quality of the studies and the overall development of the CPR against a set number of stages. Medline was searched up until June 2008, and 16 studies were reviewed that related to 9 different CPRs. These studies investigated and attempted to find clinical characteristics for responders to manipulation, stabilization exercise, physical therapy, chiropractic, traction, rehabilitation, usual care, and zygapophyseal joint injections. Eleven of these studies related to the derivation stage and five to the validation stage. The manipulation and stabilization CPRs had been the most studied. The derivation studies were mostly high quality, whereas none of the validation studies were. Some of the validation studies did not provide evidence that validated the CPR. Most of these CPRs need further evaluation before they can be applied clinically; most did not pass the lowest level of evidence hierarchy. As regards the manipulation CPR, evidence to date for its clinical utility is limited and contradictory. For the stabilization CPR, there was limited evidence that it may be considered but only with caution and in similar patients. Overall, there is limited evidence to support the general application of spinal CPRs.

Clinical prediction rules in the physiotherapy management of low back pain: a systematic review

OBJECTIVE

To identify, appraise and determine the clinical readiness of diagnostic, prescriptive and prognostic Clinical Prediction Rules (CPRs) in the physiotherapy management of Low Back Pain (LBP).

DATA SOURCES

MEDLINE, EMBASE, CINAHL, AMED and the Cochrane Database of Systematic Reviews were searched from 1990 to January 2010 using sensitive search strategies for identifying CPR and LBP studies. Citation tracking and hand-searching of relevant journals were used as supplemental strategies.

STUDY SELECTION

Two independent reviewers used a two-phase selection procedure to identify studies that explicitly aimed to develop one or more CPRs involving the physiotherapy management of LBP. Diagnostic, prescriptive and prognostic studies investigating CPRs at any stage of their development, derivation, validation, or impact-analysis, were considered for inclusion using a priori criteria. 7453 unique records were screened with 23 studies composing the final included sample.

DATA EXTRACTION

Two reviewers independently extracted relevant data into evidence tables using a standardised instrument.

DATA SYNTHESIS

Identified studies were qualitatively synthesized. No attempt was made to statistically pool the results of individual studies. The 23 scientifically admissible studies described the development of 25 unique CPRs, including 15 diagnostic, 7 prescriptive and 3 prognostic rules. The majority (65%) of studies described the initial derivation of one or more CPRs. No studies investigating the impact phase of rule development were identified.

CONCLUSIONS

The current body of evidence does not enable confident direct clinical application of any of the identified CPRs. Further validation studies utilizing appropriate research designs and rigorous methodology are required to determine the performance and generalizability of the derived CPRs to other patient populations, clinicians and clinical settings.

Spine stability: lessons from balancing a stick

This paper introduces control concepts that are important for ensuring stability. To clarify these concepts, a series of experiments using a simple task of stick balancing will be performed. The lessons from these experiments will be applied to the spine system and illustrated with clinical examples. Insight into the following will be gained: what information is used to stabilize the spine, how does noise in control affect spine performance, how has the spine evolved to allow it to be stabilized and controlled in a metabolically efficient way, how do delays in control affect spine performance, and how do different goals (i.e., maximizing performance versus minimizing fatigue) affect the logic for controlling the spine?

Abdominal muscle contraction thickness and function after specific and general exercises: a randomized controlled trial in chronic low back pain patients

The aim of this study was to assess changes in deep abdominal muscle function after 8 weeks of exercise in chronic low back pain patients. Patients (n = 109) were randomized to specific ultrasound guided, sling or general exercises. Contraction thickness ratio in transversus abdominis (TrA), obliquus internus (OI) and externus (OE), and TrA lateral slide were assessed during the abdominal drawing-in maneuver by b-mode ultrasound. Changes in abdominal muscle function were also regressed on changes in pain. Only modest effects in deep abdominal muscle function were observed, mainly due to reduced activation of OI (contraction thickness ratio: 1.42-1.22, p = 0.01) and reduced TrA lateral slide (1.26-1.01 cm, p = 0.02) in the ultrasound group on the left side. Reduced pain was associated with increased TrA and reduced OI contraction ratio (R(2) = 0.18). It is concluded that 6-8 treatments with specific or general exercises for chronic low back patients attained only marginal changes in contraction thickness and slide in deep abdominal muscles, and could only to a limited extent account for reductions in pain.

Kinematic analysis of dynamic lumbar motion in patients with lumbar segmental instability using digital videofluoroscopy

The study design is a prospective, case-control. The aim of this study was to develop a reliable measurement technique for the assessment of lumbar spine kinematics using digital video fluoroscopy in a group of patients with low back pain (LBP) and a control group. Lumbar segmental instability (LSI) is one subgroup of nonspecific LBP the diagnosis of which has not been clarified. The diagnosis of LSI has traditionally relied on the use of lateral functional (flexion-extension) radiographs but use of this method has proven unsatisfactory.Fifteen patients with chronic low back pain suspected to have LSI and 15 matched healthy subjects were recruited. Pulsed digital videofluoroscopy was used to investigate kinematics of lumbar motion segments during flexion and extension movements in vivo. Intersegmental linear translation and angular displacement, and pathway of instantaneous center of rotation (PICR) were calculated for each lumbar motion segment. Movement pattern of lumbar spine between two groups and during the full sagittal plane range of motion were analyzed using ANOVA with repeated measures design. Intersegmental linear translation was significantly higher in patients during both flexion and extension movements at L5-S1 segment (p < 0.05). Arc length of PICR was significantly higher in patients for L1-L2 and L5-S1 motion segments during extension movement (p < 0.05). This study determined some kinematic differences between two groups during the full range of lumbar spine. Devices, such as digital videofluoroscopy can assist in identifying better criteria for diagnosis of LSI in otherwise nonspecific low back pain patients in hope of providing more specific treatment.

Manual physical assessment of spinal segmental motion: intent and validity

Validity of a clinical test can be defined as the extent to which the test actually assesses what it is intended to assess. In order to investigate the validity of manual physical assessment of the spine, it is therefore essential to establish what physical therapists intend to assess when they are applying these tests. The aims of this study were to (1) establish what manual physical therapists are intending to assess while applying passive intervertebral motion tests; and (2) examine the face validity and content validity for manual physical assessment of the spine. We surveyed 1502 members of the national manual physical therapist organisations of New Zealand and the United States of America using a web-based survey instrument. Sixty-six percent of 466 respondents believed passive accessory intervertebral motion (PAIVM) tests were valid for assessing quantity of segmental motion, and 76% believed passive physiologic intervertebral motion (PPIVM) tests were valid for assessing quantity of segmental motion. Ninety-eight percent of manual physical therapists base treatment decisions at least in part on the results of segmental motion tests. Quality of resistance to passive segmental motion was considered of greater importance than quantity of kinematic motion during PAIVM tests, while the quality of complex kinematic motion was considered of greater importance than quantity of displacement kinematics during PPIVM tests. Manual physical therapists accept the face validity of manual physical assessment of spinal segmental motion to a great extent, however a minority voice scepticism. Content validity is dominated by concepts of segmental kinematics and the force-displacement relationship. Intent of assessment does, however, vary widely between therapists. These data will inform the design of concurrent validity studies. Further work is recommended to increase consistency of intent, methodology and terminology in manual physical assessment of the spine.