Three-dimensional architecture and moment arms of human rotator cuff muscles in vivo: Interindividual, intermuscular, and intramuscular variations.

The human rotator cuff consists of four muscles, each with a complex, multipennate architecture. Despite the functional and clinical importance, the architecture of the human rotator cuff has yet to be clearly described in humans in vivo. The purpose of this study was to investigate the intramuscular, intermuscular, and interindividual variations in architecture and moment arms of the human rotator cuff. Muscle volumes, fascicle lengths, physiological cross-sectional areas (PCSAs), pennation angles, and moment arms of all four rotator cuff muscles were measured from mDixon and diffusion tensor imaging (DTI) scans of the right shoulders of 20 young adults. In accordance with the most detailed dissections available to date, we found substantial intramuscular variation in fascicle length (coefficients of variation (CVs) ranged from 26% to 40%) and pennation angles (CVs ranged from 56% to 62%) in all rotator cuff muscles. We also found substantial intermuscular and interindividual variations in muscle volumes, but relatively consistent mean fascicle lengths, pennation angles, and moment arms (CVs for all ≤17%). Moreover, when expressed as a proportion of total rotator cuff muscle volume, the volumes of individual rotator cuff muscles were highly consistent between individuals and sexes (CVs ≤16%), suggesting that rotator cuff muscle volumes scale uniformly, at least in a younger population without musculoskeletal problems. Together, these data indicate limited interindividual and intermuscular variability in architecture, which may simplify scaling routines for musculoskeletal models. However, the substantial intramuscular variation in architecture questions the validity of previously reported mean architectural parameters to adequately describe rotator cuff function.

Exergame and cognitive training for preventing falls in community-dwelling older people: a randomized controlled trial.

Exergame training, in which video games are used to promote exercise, can be tailored to address cognitive and physical risk factors for falls and is a promising method for fall prevention in older people. Here, we performed a randomized clinical trial using the smart±step gaming system to examine the effectiveness of two home-based computer game interventions, seated cognitive training and step exergame training, for fall prevention in community-dwelling older people, as compared with a minimal-intervention control group. Participants aged 65 years or older (n = 769, 71% female) living independently in the community were randomized to one of three arms: (1) cognitive training using a computerized touchpad while seated, (2) exergame step training on a computerized mat or (3) control (provided with an education booklet on healthy ageing and fall prevention). The rate of falls reported monthly over 12 months-the primary outcome of the trial-was significantly reduced in the exergame training group compared with the control group (incidence rate ratio = 0.74, 95% confidence interval = 0.56-0.98), but was not statistically different between the cognitive training and control groups (incidence rate ratio = 0.86, 95% confidence interval = 0.65-1.12). No beneficial effects of the interventions were found for secondary outcomes of physical and cognitive function, and no serious intervention-related adverse events were reported. The results of this trial support the use of exergame step training for preventing falls in community-dwelling older people. As this intervention can be conducted at home and requires only minimal equipment, it has the potential for scalability as a public health intervention to address the increasing problem of falls and fall-related injuries. Australian and New Zealand Clinical Trial Registry identifier: ACTRN12616001325493 .

Human lower leg muscles grow asynchronously.

Muscle volume must increase substantially during childhood growth to generate the power required to propel the growing body. One unresolved but fundamental question about childhood muscle growth is whether muscles grow at equal rates; that is, if muscles grow in synchrony with each other. In this study, we used magnetic resonance imaging (MRI) and advances in artificial intelligence methods (deep learning) for medical image segmentation to investigate whether human lower leg muscles grow in synchrony. Muscle volumes were measured in 10 lower leg muscles in 208 typically developing children (eight infants aged less than 3 months and 200 children aged 5 to 15 years). We tested the hypothesis that human lower leg muscles grow synchronously by investigating whether the volume of individual lower leg muscles, expressed as a proportion of total lower leg muscle volume, remains constant with age. There were substantial age-related changes in the relative volume of most muscles in both boys and girls (p < 0.001). This was most evident between birth and five years of age but was still evident after five years. The medial gastrocnemius and soleus muscles, the largest muscles in infancy, grew faster than other muscles in the first five years. The findings demonstrate that muscles in the human lower leg grow asynchronously. This finding may assist early detection of atypical growth and allow targeted muscle-specific interventions to improve the quality of life, particularly for children with neuromotor conditions such as cerebral palsy.

Early and intensive motor training to enhance neurological recovery in people with spinal cord injury: trial protocol.

STUDY DESIGN: Protocol for a multi-centre randomised controlled trial (the SCI-MT trial). OBJECTIVES: To determine whether 10 weeks of intensive motor training enhances neurological recovery in people with recent spinal cord injury (SCI). SETTING: Fifteen spinal injury units in Australia, Scotland, England, Italy, Netherlands, Norway, and Belgium. METHODS: A pragmatic randomised controlled trial will be undertaken. Two hundred and twenty people with recent SCI (onset in the preceding 10 weeks, American Spinal Injuries Association Impairment Scale (AIS) A lesion with motor function more than three levels below the motor level on one or both sides, or an AIS C or D lesion) will be randomised to receive either usual care plus intensive motor training (12 h of motor training per week for 10 weeks) or usual care alone. The primary outcome is neurological recovery at 10 weeks, measured with the Total Motor Score from the International Standards for Neurological Classification of SCI. Secondary outcomes include global measures of motor function, ability to walk, quality of life, participants' perceptions about ability to perform self-selected goals, length of hospital stay and participants' impressions of therapeutic benefit at 10 weeks and 6 months. A cost-effectiveness study and process evaluation will be run alongside the trial. The first participant was randomised in June 2021 and the trial is due for completion in 2025. CONCLUSIONS: The findings of the SCI-MT Trial will guide recommendations about the type and dose of inpatient therapy that optimises neurological recovery in people with SCI. TRIAL REGISTRATION: ACTRN12621000091808 (1.2.2021).

Three-dimensional skeletal muscle architecture in the lower legs of living human infants.

Little is known about the skeletal muscle architecture of living humans at birth. In this study, we used magnetic resonance imaging (MRI) to measure the volumes of ten muscle groups in the lower legs of eight human infants aged less than three months. We then combined MRI and diffusion tensor imaging (DTI) to provide detailed, high-resolution reconstructions and measurements of moment arms, fascicle lengths, physiological cross-sectional areas (PCSAs), pennation angles and diffusion parameters of the medial (MG) and lateral gastrocnemius (LG) muscles. On average, the total lower leg muscle volume was 29.2 cm3. The largest muscle was the soleus muscle with a mean volume of 6.5 cm3. Compared to the LG muscles, the MG muscles had, on average, greater volumes (by ∼35%) and greater PCSAs (by ∼63%) but similar ankle-to-knee moment arm ratios (∼0.1 difference), fascicle lengths (∼5.7 mm difference) and pennation angles (∼2.7° difference). The MG data were compared with data previously collected from adults. The MG muscles of adults had, on average, a 63-fold greater volume, a 36-fold greater PCSA, and 1.7-fold greater fascicle length. This study demonstrates the feasibility of using MRI and DTI to reconstruct the three-dimensional architecture of skeletal muscles in living human infants. It is shown that, between infancy and adulthood, MG muscle fascicles grow primarily in cross-section rather than in length.

Arthroscopic capsular shift surgery in patients with atraumatic shoulder joint instability: a randomised, placebo-controlled trial.

OBJECTIVES: To determine the effect of arthroscopic capsular shift surgery on pain and functional impairment for people with atraumatic shoulder (glenohumeral) joint instability. METHODS: We conducted a randomised, placebo-controlled clinical trial in a specialist secondary care facility. Patients aged 18 years and over who reported insecurity (apprehension) in their shoulder joint and had evidence of capsulolabral damage on arthroscopic examination were included. Patients were excluded if their shoulder apprehension symptoms were precipitated by a high velocity shoulder injury, they had bony or neural damage, a rotator cuff or labral tear, or previous surgery on the symptomatic shoulder. Sixty-eight participants were randomised and received diagnostic arthroscopy, followed by arthroscopic capsular shift or diagnostic arthroscopy alone. All participants received the same postoperative clinical care. The primary outcome was pain and functional impairment measured with the Western Ontario Shoulder Instability Index. The prespecified minimum clinically important effect was a reduction in pain and disability of 10.4 points. RESULTS: Mean reductions in pain and functional impairment for both groups were similar. Compared with diagnostic arthroscopy, arthroscopic capsular shift increased pain and functional impairment by means of 5 points (95% CI -6 to 16 points) at 6 months, 1 point (95% CI -11 to 13 points) at 12 months and 2 points (95% CI -12 to 17 points) at 24 months. CONCLUSIONS: Compared with diagnostic arthroscopy alone, arthroscopic capsular shift confers, at best, only minimal clinically important benefit in the medium term. TRIAL REGISTRATION NUMBER: NCT01751490.

Post-fracture serum cytokine levels are not associated with a later diagnosis of complex regional pain syndrome: a case-control study nested in a prospective cohort study.

BACKGROUND: Complex Regional Pain Syndrome (CRPS) is a disabling pain disorder that is most common after a distal limb fracture. While the acute systemic immune response to the injury is thought to play a role in the development of CRPS, this hypothesis has never been tested directly. Thus, we evaluated whether elevated levels of circulating pro-inflammatory cytokines early after a fracture were associated with the development of CRPS. METHODS: We conducted a case-control study nested within a prospective cohort study. Individuals with wrist and/or hand fractures were recruited from specialist hand units. Baseline clinical data were obtained from participants within 28 days of fracture. CRPS status was determined 16 weeks after the fracture using a two-stage diagnostic process. Cytokine assays were obtained from all cases (defined using the Budapest criteria) and a random sample of those who did not have CRPS at 16 weeks. We calculated odds ratios with 95% confidence intervals to determine the risk of CRPS associated with the expression of each of 25 cytokines. RESULTS: Baseline data were collected for 702 consenting participants, of whom 535 provided blood samples. Follow-up at 16 weeks was 97.2%. 15 (2.2% of the cohort) met the Budapest CRPS criteria and 69 (including those who met the Budapest criteria; 9.8%) met the International Association for the Study of Pain (IASP) CRPS criteria. In all of the primary analyses (using Budapest criteria) and 49/50 secondary analyses (using IASP criteria), 95% confidence intervals for the association between cytokine levels and the risk of subsequently developing CRPS included the null value (OR = 1). However, the confidence intervals were wide. CONCLUSION: There was no evidence that early post-injury expression of systemic cytokines was associated with a CRPS diagnosis 16 weeks after injury. This study does not provide support for the hypothesis that innate immune activation has a determinative role in the development of CRPS.

Diagnostic labels and advice for rotator cuff disease influence perceived need for shoulder surgery: an online randomised experiment.

QUESTION: What are the effects of diagnostic labels and advice, and interactions between labels and advice, on perceived need for shoulder surgery for rotator cuff disease? DESIGN: 2×2 factorial online randomised experiment. PARTICIPANTS: People with shoulder pain. INTERVENTION: Participants read a scenario describing a patient with rotator cuff disease and were randomised to bursitis label plus guideline-based advice, bursitis label plus treatment recommendation, rotator cuff tear label plus guideline-based advice, and rotator cuff tear label plus treatment recommendation. Guideline-based advice included encouragement to stay active and positive prognostic information. Treatment recommendation stressed that treatment is needed for recovery. OUTCOME MEASURES: Perceived need for surgery (primary outcome), imaging, an injection, a second opinion and to see a specialist; and perceived seriousness of the condition, recovery expectations, impact on work performance and need to avoid work. RESULTS: A total of 2,024 responses (99.8% of 2,028 randomised) were analysed. Labelling as bursitis (versus rotator cuff tear) decreased perceived need for surgery (mean effect -0.5 on a 0-to-10 scale, 98.3% CI -0.7 to -0.2), imaging and to see a specialist, and perceived seriousness of the condition and need to avoid work. Guideline-based advice (versus treatment recommendation) decreased perceived need for surgery (mean effect -1.0, 98.3% CI -1.3 to -0.7), imaging, an injection, a second opinion and to see a specialist, and perceived seriousness of the condition and recovery expectations. There was little to no evidence of an advice label interaction for any outcome. CONCLUSION: Labels and advice influenced perceived need for surgery and other secondary outcomes in people with rotator cuff disease, with larger effects for advice. There was evidence of little or no interaction between labels and advice for any outcome, but the additive effect of labels and advice appeared large for some outcomes (eg, perceived need for imaging and perceived seriousness of the condition). TRIAL REGISTRATION: ACTRN12621001370897.

Effect of Graded Sensorimotor Retraining on Pain Intensity in Patients With Chronic Low Back Pain: A Randomized Clinical Trial.

Importance: The effects of altered neural processing, defined as altering neural networks responsible for perceptions of pain and function, on chronic pain remains unclear. Objective: To estimate the effect of a graded sensorimotor retraining intervention (RESOLVE) on pain intensity in people with chronic low back pain. Design, Setting, and Participants: This parallel, 2-group, randomized clinical trial recruited participants with chronic (>3 months) nonspecific low back pain from primary care and community settings. A total of 276 adults were randomized (in a 1:1 ratio) to the intervention or sham procedure and attention control groups delivered by clinicians at a medical research institute in Sydney, Australia. The first participant was randomized on December 10, 2015, and the last was randomized on July 25, 2019. Follow-up was completed on February 3, 2020. Interventions: Participants randomized to the intervention group (n = 138) were asked to participate in 12 weekly clinical sessions and home training designed to educate them about and assist them with movement and physical activity while experiencing lower back pain. Participants randomized to the control group (n = 138) were asked to participate in 12 weekly clinical sessions and home training that required similar time as the intervention but did not focus on education, movement, and physical activity. The control group included sham laser and shortwave diathermy applied to the back and sham noninvasive brain stimulation. Main Outcomes and Measures: The primary outcome was pain intensity at 18 weeks, measured on an 11-point numerical rating scale (range, 0 [no pain] to 10 [worst pain imaginable]) for which the between-group minimum clinically important difference is 1.0 point. Results: Among 276 randomized patients (mean [SD] age, 46 [14.3] years; 138 [50%] women), 261 (95%) completed follow-up at 18 weeks. The mean pain intensity was 5.6 at baseline and 3.1 at 18 weeks in the intervention group and 5.8 at baseline and 4.0 at 18 weeks in the control group, with an estimated between-group mean difference at 18 weeks of -1.0 point ([95% CI, -1.5 to -0.4]; P = .001), favoring the intervention group. Conclusions and Relevance: In this randomized clinical trial conducted at a single center among patients with chronic low back pain, graded sensorimotor retraining, compared with a sham procedure and attention control, significantly improved pain intensity at 18 weeks. The improvements in pain intensity were small, and further research is needed to understand the generalizability of the findings. Trial Registration: ANZCTR Identifier: ACTRN12615000610538.

Incidence, severity and time course of pressure injuries over the first two years following discharge from hospital in people with spinal cord injuries in Bangladesh.

DESIGN: Cohort study embedded in a clinical trial. SETTING: Community, Bangladesh. OBJECTIVES: To determine the incidence, severity and time course of pressure injuries over the first two years following discharge from hospital in people with spinal cord injuries (SCI) in Bangladesh. METHODS: Participants (n = 186) were contacted by telephone 39 times and assessed face-to-face 4 to 6 times over the two years following discharge. At each point of contact the presence and severity of pressure injuries were determined using the Pressure Ulcer Scale for Healing (PUSH). Survival analyses were conducted to determine the time course of development of pressure injuries and recovery from pressure injuries. Lasso regression was used to construct multivariable prediction models. RESULTS: Seventy-seven participants (41%; 95% CI 34% to 49%) developed at least one pressure injury in the first two years after discharge (incidence rate 0.27 per person-year, 95% CI 0.22 to 0.34). Most pressure injuries were on the sacrum (23%). Pressure injuries took a median (IQR) of 40 (29 to 57) days to heal. The median (IQR) peak PUSH score was 11.0/17 (8.0 to 13.5). The multivariable prediction models had poor predictive properties (maximum c-statistic 0.75). CONCLUSION: Pressure injuries impose a large health burden on people with SCI in Bangladesh. However, they are difficult to predict, treat and prevent. Further research is needed to identify who is at most risk and to find solutions for the treatment and prevention of pressure injuries in Bangladesh and other low-middle income countries.

Deep learning methods for automatic segmentation of lower leg muscles and bones from MRI scans of children with and without cerebral palsy.

Cerebral palsy is a neurological condition that is known to affect muscle growth. Detailed investigations of muscle growth require segmentation of muscles from MRI scans, which is typically done manually. In this study, we evaluated the performance of 2D, 3D, and hybrid deep learning models for automatic segmentation of 11 lower leg muscles and two bones from MRI scans of children with and without cerebral palsy. All six models were trained and evaluated on manually segmented T1 -weighted MRI scans of the lower legs of 20 children, six of whom had cerebral palsy. The segmentation results were assessed using the median Dice similarity coefficient (DSC), average symmetric surface distance (ASSD), and volume error (VError) of all 13 labels of every scan. The best performance was achieved by H-DenseUNet, a hybrid model (DSC 0.90, ASSD 0.5 mm, and VError 2.6 cm3 ). The performance was equivalent to the inter-rater performance of manual segmentation (DSC 0.89, ASSD 0.6 mm, and VError 3.3 cm3 ). Models trained with the Dice loss function outperformed models trained with the cross-entropy loss function. Near-optimal performance could be attained using only 11 scans for training. Segmentation performance was similar for scans of typically developing children (DSC 0.90, ASSD 0.5 mm, and VError 2.8 cm3 ) and children with cerebral palsy (DSC 0.85, ASSD 0.6 mm, and VError 2.4 cm3 ). These findings demonstrate the feasibility of fully automatic segmentation of individual muscles and bones from MRI scans of children with and without cerebral palsy.

Negligible epimuscular myofascial force transmission between the human rectus femoris and vastus lateralis muscles in passive conditions.

PURPOSE: There have been contradictory reports of the effects of epimuscular myofascial force transmission in humans. This study investigated the transmission of myofascial force to the human vastus lateralis muscle by determining whether vastus lateralis slack angle changed with hip angle. Since the distance between the origin and insertion of the vastus lateralis muscle does not change when hip angle changes, any change in vastus lateralis slack angle with hip position can be attributed to epimuscular myofascial force transmission. METHODS: Nineteen young adults were tested in hip flexed ([Formula: see text]) and neutral ([Formula: see text]) positions. Ultrasound images of the vastus lateralis muscle were obtained as the knee was passively flexed at [Formula: see text]/s. The knee angle at which vastus lateralis muscle fascicles began to lengthen was used to identify muscle slack angle. RESULTS: Overall, there was a negligible effect of hip position on vastus lateralis slack angle ([Formula: see text] [[Formula: see text] to 1.9]; mean [95% confidence interval]). However, a small and variable effect was noted in 3/19 participants. CONCLUSION: This result indicates that, over the range of joint angles tested here, there is little or no epimuscular myofascial force transmission between the vastus lateralis muscle and neighbouring bi-articular structures under passive conditions. More broadly, this result provides additional evidence that epimuscular myofascial force transmission tends to be small and variable under passive conditions in healthy human muscle.

Clinical Course of Pain and Function Following Total Knee Arthroplasty: A Systematic Review and Meta-Regression.

BACKGROUND: Total knee arthroplasty (TKA) is widely considered a successful intervention for osteoarthritis and other degenerative knee diseases. This study addresses the need for a high-quality meta-analysis that outlines the clinical course of pain and function post-TKA. METHODS: The review included prospective cohort studies assessing pain or function of patients undergoing primary TKA at baseline (preoperatively) and at least 2 additional time points including one at least 12 months postoperatively. Two reviewers independently screened references, extracted data, and assessed risk of bias using the Quality in Prognosis Studies tool. The time course of recovery of pain and function was modeled using fractional polynomial meta-regression. RESULTS: In total, 191 studies with 59,667 patients were included, most with low risk of bias. The variance-weighted mean pain score (/100, 0 = no pain) was 64.0 (95% confidence interval [CI] 60.2-67.7) preoperatively, 24.1 (95% CI 20.3-27.9) at 3 months, 20.4 (95% CI 16.7-24.0) at 6 months, and 16.9 (95%CI 13.6-20.3) at 12 months, and remained low (10.1; 95% CI 4.8-15.4) at 10 years postoperatively. The variance-weighted mean function score (/100, 0 = worst function) was 47.1 (95% CI 45.7-48.4) preoperatively, 72.8 (95% CI 71.3-74.4) at 3 months, 76.3 (95% CI 74.7-77.8) at 6 months, and 78.1 (95%CI 76.4-79.7) at 12 months. Function scores were good (79.7; 95% CI 77.9-81.5) at 10 years postoperatively. CONCLUSION: Patients undergoing primary TKA can expect a large and rapid but incomplete recovery of pain and function in the first postoperative year. At 10 years, the gains in pain scores may still remain while there is an improvement in function.

MRI-based Measurement of Effects of Strength Training on Intramuscular Fat in People with and without Spinal Cord Injury.

INTRODUCTION: The accurate quantification of the proportion of fat in human muscles could help monitor disease status and test effectiveness of interventions in people with neurological conditions whose skeletal muscles are frequently infiltrated with fat. METHODS: We compared two commonly used magnetic resonance imaging methods to quantify fat in muscles. Measurements were obtained before and after 6 or 8 wk of strength training in a total of 116 muscles spanning the range of intramuscular fat proportions observed in able-bodied young adults and people with spinal cord injury. RESULTS: We successfully measured fat proportions in all muscles using the mDixon method but were unable to obtain plausible measurements with the T1-weighted method from muscles of able-bodied individuals or from the leaner 23% of muscles of people with spinal cord injury (muscles with less than approximately 8% fat). In muscles with more fat, measurements obtained with the two methods agreed well (intraclass correlation coefficient, 0.88; mean absolute difference, 5%). We also found that, compared with the T1-weighted method, the mDixon method provides a more detailed characterization of fat infiltration in muscle and a less variable measurement of the effect of training on the proportion of fat. The mDixon method showed that 6 or 8 wk of strength training did not appreciably change the proportion of intramuscular fat in either people with spinal cord injury or able-bodied people. CONCLUSION: On the basis of these findings, we recommend the use of mDixon methods in preference to T1-weighted methods to determine the effectiveness of interventions aimed at reducing intramuscular fat.

Clinical course of patients with low back pain following an emergency department presentation: a systematic review and meta-analysis.

INTRODUCTION: Low back pain, and especially non-specific low back pain, is a common cause of presentation to the emergency department (ED). Although these patients typically report relatively high pain intensity, the clinical course of their pain and disability remains unclear. Our objective was to review the literature and describe the clinical course of non-specific low back pain after an ED visit. METHODS: Electronic searches were conducted using MEDLINE, CINAHL and EMBASE from inception to March 2019. We screened for cohort studies or randomised trials investigating pain or disability in patients with non-specific low back pain presenting to EDs. We excluded studies that enrolled participants with minimal pain or disability scores at baseline. Two reviewers independently screened the full texts, extracted the data and assessed risk of bias and quality of evidence. Estimates of pain and disability were converted to a common 0-100 scale. We estimated pooled means and 95% CIs of pain and disability as a function of time since ED presentation. RESULTS: Eight studies (nine publications) with a total of 1994 patients provided moderate overall quality evidence of the expected clinical course of low back pain after an ED visit. Seven of the eight studies were assessed to have a low risk of bias. At the time of the ED presentation, the pooled estimate of the mean pain score on a 0-100 scale was 71.0 (95% CI 64.2-77.9). This reduced to 46.1 (95% CI 37.2-55.0) after 1 day, 41.8 (95% CI 34.7 to 49.0) after 1 week and 13.5 (95% CI 5.8-21.3) after 26 weeks. The course of disability followed a similar pattern. CONCLUSIONS: Patients presenting to EDs with non-specific low back pain experience rapid reductions in pain intensity, but on average symptoms persisted 6 months later. This review can be used to educate patients so they can have realistic expectations of their recovery.

A community-based intervention to prevent serious complications and death 2 years after discharge in people with spinal cord injury in Bangladesh (CIVIC): a randomised trial.

STUDY DESIGN: Randomised controlled trial. OBJECTIVES: To determine the effectiveness of a sustainable community-based intervention designed to prevent serious complications and death 2 years after discharge in people with spinal cord injury in Bangladesh. SETTING: Bangladesh. METHODS: A pragmatic randomised controlled trial was undertaken. People who had sustained a spinal cord injury in the preceding 2 years, were wheelchair-dependent, and were about to be discharged from hospital in Bangladesh were recruited and randomised to an Intervention or Control group using a concealed allocation procedure stratified by level of lesion (tetraplegia/paraplegia). Participants in the Intervention group received 36 phone calls and three home visits over the first 2 years following discharge. All participants received usual post-discharge care. Survival status and date of death were determined by blinded assessors 2 years after randomisation. RESULTS: Between July 2015 and March 2018, 410 participants were randomised (204 to Intervention, 206 to Control). There was no loss to follow up. At 2 years, 15 (7.4%) participants in the Intervention group and 16 (7.8%) participants in the Control group had died (hazard ratio from unadjusted Cox model = 0.93 [95% CI, 0.46 to 1.89]; p from log rank test 0.85). There were no clinically important or statistically significant average causal effects of intervention on the incidence or severity of complications. CONCLUSION: A program of community-based care for people with recent spinal cord injury in Bangladesh involving frequent phone contact and occasional in-person contact with a health professional after discharge from hospital is no better at preventing death at 2 years than usual care.

Intramuscular fat in children with unilateral cerebral palsy.

BACKGROUND: Many children with cerebral palsy develop muscle contractures. The mechanisms of contracture are not well understood. We investigated the possibility that, because fat is stiffer than passive muscle, elevated intramuscular fat contributes to contracture. In this cross-sectional study, we compared the quantity and distribution of intramuscular fat in muscles from typically developing children and children with cerebral palsy who have contractures. METHODS: mDixon magnetic resonance images were obtained from the legs of 20 ambulant children with unilateral spastic cerebral palsy who had ankle contractures (mean age 11 SD 3 years, 13 male, mean moderate level contracture) and 20 typically developing children (mean age 11 SD 4 years, 13 male). The images were analyzed to quantify the intramuscular fat fraction of the medial gastrocnemius muscles. The amount and distribution of intramuscular fat were compared between muscles of children with cerebral palsy and typically developing children. FINDINGS: In typically developing children, the medial gastrocnemius muscles had a mean intramuscular fat fraction of 4.7% (SD 1.6%). In children with cerebral palsy, the mean intramuscular fat fractions in the more- and less-affected medial gastrocnemius muscle were 11.4% (8.1%) and 6.9% (3.4%) respectively. There were small but statistically significant regional differences in the distribution of intramuscular fat. There was no evidence of a relationship between intramuscular fat fraction and severity of contracture. INTERPRETATION: Children with cerebral palsy have higher proportions of intramuscular fat than typically developing children. There is no clear relationship between intramuscular fat fraction and dorsiflexion range of motion in children with cerebral palsy.

History-dependence of muscle slack length in humans: effects of contraction intensity, stretch amplitude, and time.

The slack length of a relaxed skeletal muscle can be reduced by isometric contraction at short lengths ("contract-short conditioning"). This study explored how the effect of contract-short conditioning on muscle slack length is modified by 1) the intensity of the contraction, 2) the delay between the contraction and measurement of slack length, and 3) the amplitude of a stretch delivered to the relaxed muscle after the contraction. Muscle fascicles in the human vastus lateralis muscle were observed with ultrasound imaging while the relaxed muscle was lengthened by flexing the knee. The knee angle at which muscle fascicle slack was taken up was used as a proxy for muscle slack length. Conditioning the muscle with voluntary isometric (fixed-end) contractions at short muscle lengths reduced vastus lateralis muscle slack length, measured 60 s later, by a mean of 10°. This effect was independent of contraction intensity from 5% to 100% maximal voluntary contraction. The effect was largest when first observed 5 s after the contraction, decayed about one-third by 60 s, and then remained nearly constant until the last observation 5 min after the contraction. A slow stretch given to the relaxed muscle after contract-short conditioning increased slack length (i.e., reduced the effect of contract-short conditioning). Slack length increased nonlinearly with stretch amplitude. Very large stretches (>30°, possibly as large as 90°) were required to abolish the effect of contract-short conditioning. The phenomena described here share some characteristics with, and may involve similar mechanisms to, passive force enhancement and muscle thixotropy.NEW & NOTEWORTHY The slack length of a relaxed human skeletal muscle is not fixed; it can be modified by contraction and stretch. Contraction of the human vastus lateralis muscle at short lengths reduces the muscle's slack length. Even very weak contractions are sufficient to induce this effect. The effect persists for at least 5 min but can be reduced or abolished with a large-amplitude passive stretch.

A description of the primary studies of diagnostic test accuracy indexed on the DiTA database.

BACKGROUND AND PURPOSE: PEDro (the Physiotherapy Evidence Database) is a widely used, comprehensive, freely available, online database that indexes studies of the effectiveness of physiotherapy interventions. We have recently built another database, called DiTA, on the same platform as PEDro. DiTA provides a comprehensive index of studies of the accuracy of diagnostic tests used by physiotherapists. This study aims to describe the number and scope of such studies. METHODS: A comprehensive search was conducted for studies of the accuracy of diagnostic tests. The search was conducted on the MEDLINE, EMBASE and CINAHL databases from their inceptions to November 2018. Subsequently, monthly searches have updated the database. To be included on DiTA, studies need to investigate (a) both a pathology and patients that a physiotherapist could assess in clinical practice, and (b) an index test that a physiotherapist would perform themselves rather than one which they would request. RESULTS: To date, the searches have yielded 44,884 titles. Screening has identified 1,419 reports that meet the inclusion criteria. The most frequently studied subdisciplines are "musculoskeletal" (1,050/1,419; 74.0%) and "cardiothoracics" (241; 17.0%); the most frequently studied categories of pathologies are joint pathologies (463; 32.6%) and nervous system pathologies (175; 12.3%); and the most frequently studied body part is the "lower leg or knee" (232; 16.3%). Most studies investigate index tests which are "physical examination" procedures (851; 60.0%); fewer investigate "questions or questionnaires" (420; 29.6%) and "health technologies" (351; 24.7%). DISCUSSION: There is a rapidly growing body of evidence on the accuracy of diagnostic tests relevant to most physiotherapy subdisciplines. While the volume of evidence is substantial, it is not yet clear how much of the evidence is of good enough quality to support clinical decision-making.