Joline E. Brandenburg

Ultrasound elastography: the new frontier in direct measurement of muscle stiffness.

The use of brightness-mode ultrasound and Doppler ultrasound in physical medicine and rehabilitation has increased dramatically. The continuing evolution of ultrasound technology has also produced ultrasound elastography, a cutting-edge technology that can directly measure the mechanical properties of tissue, including muscle stiffness. Its real-time and direct measurements of muscle stiffness can aid the diagnosis and rehabilitation of acute musculoskeletal injuries and chronic myofascial pain. It can also help monitor outcomes of interventions affecting muscle in neuromuscular and musculoskeletal diseases, and it can better inform the functional prognosis. This technology has implications for even broader use of ultrasound in physical medicine and rehabilitation practice, but more knowledge about its uses and limitations is essential to its appropriate clinical implementation. In this review, we describe different ultrasound elastography techniques for studying muscle stiffness, including strain elastography, acoustic radiation force impulse imaging, and shear-wave elastography. We discuss the basic principles of these techniques, including the strengths and limitations of their measurement capabilities. We review the current muscle research, discuss physiatric clinical applications of these techniques, and note directions for future research.

Shear wave elastography of passive skeletal muscle stiffness: Influences of sex and age throughout adulthood

BACKGROUND Numerous structural and compositional changes - related not only to age, but also activity level and sex - may affect skeletal muscle stiffness across the adult age-span. Measurement techniques available thus far have largely limited passive stiffness evaluations to those of entire joints and muscle-tendon units. Shear wave elastography is an increasingly popular ultrasound technique for evaluating the mechanical properties of skeletal muscle tissue. The purpose of this study was to quantify the passive stiffness, or shear modulus, of the biceps brachii throughout adulthood in flexed and extended elbow positions. We hypothesized that shear modulus would be higher in males relative to females, and with advanced age in both sexes. METHODS Shear wave elastography quantified biceps brachii stiffness at 90° elbow flexion and full extension in a large sample of adults between 21 and 94 years old (n=133; 47 males). FINDINGS Regression analysis found sex and age were significant parameters for older adults (>60 years) in full extension. As expected, shear modulus values increased with advancing age; however, shear modulus values for females tended to be higher than those for males. INTERPRETATION This study begins to establish normative trends for skeletal muscle shear modulus throughout adulthood. Specifically, this work establishes for the first time that the higher passive joint torque often found in males relative to females likely relates to parameters other than muscle shear modulus. Indeed, perhaps increases in skeletal muscle passive stiffness, though potentially altering the length-tension curve, serve a protective role - maintaining the tendon-muscle-tendon length-tension curve within a functional range.

Feasibility and Reliability of Quantifying Passive Muscle Stiffness in Young Children by Using Shear Wave Ultrasound Elastography

The purpose of this study was to investigate the feasibility and reliability of passive muscle stiffness measurements in children by shear wave ultrasound elastography.

Managing Chronic Pain in Children and Adolescents: A Clinical Review

Chronic pain in children and adolescents can be difficult for a single provider to manage in a busy clinical setting. Part of this difficulty is that pediatric chronic pain not only impacts the child but also the families of these children. In this review article, we discuss etiology and pathophysiology of chronic pain, along with variables that impact the severity of chronic pain and functional loss. We review diagnosis and management of selected chronic pain conditions in pediatric patients, including headache, low back pain, hypermobility, chronic fatigue, postural orthostatic tachycardia syndrome, abdominal pain, fibromyalgia, and complex regional pain syndrome. For each condition, we create a road map that contains therapy prescriptions, exercise recommendations, and variables that may influence pain severity. Potential medications for these pain conditions and associated symptoms are reviewed. A multidisciplinary approach for managing children with these conditions, including pediatric pain rehabilitation programs, is emphasized. Lastly, we discuss psychological factors and interventions for pediatric chronic pain and potential complementary and alternative natural products and interventions.

Quantifying passive muscle stiffness in children with and without cerebral palsy using ultrasound shear wave elastography

The aim of this study was to compare passive muscle stiffness in children with cerebral palsy (CP) and children with typical development using a novel ultrasound technique: ultrasound shear wave elastography (SWE).

A common data language for clinical research studies: the National Institute of Neurological Disorders and Stroke and American Academy for Cerebral Palsy and Developmental Medicine Cerebral Palsy Common Data Elements Version 1.0 recommendations

To increase the efficiency and effectiveness of clinical research studies, cerebral palsy (CP) specific Common Data Elements (CDEs) were developed through a partnership between the National Institute of Neurological Disorders and Stroke (NINDS) and the American Academy of Cerebral Palsy and Developmental Medicine (AACPDM). International experts reviewed existing NINDS CDEs and tools used in studies of children and young people with CP. CDEs were compiled, subjected to internal review, and posted online for external public comment in September 2016. Guided by the International Classification of Functioning, Disability and Health framework, CDEs were categorized into six domains: (1) participant characteristics; (2) health, growth, and genetics; (3) neuroimaging; (4) neuromotor skills and functional assessments; (5) neurocognitive, social, and emotional assessments; and (6) engagement and quality of life. Version 1.0 of the NINDS/AACPDM CDEs for CP is publicly available on the NINDS CDE and AACPDM websites. Global use of CDEs for CP will standardize data collection, improve data quality, and facilitate comparisons across studies. Ongoing collaboration with international colleagues, industry, and people with CP and their families will provide meaningful feedback and updates as additional evidence is obtained. These CDEs are recommended for NINDS‐funded research for CP.

Shear Wave Elastography for Noninvasive Quantification of Passive Muscle Stiffness in Typically Developing Children

Disclosures: J. E. Brandenburg, No Disclosures: I Have Nothing To Disclose. Objective: Increased passive resistance, or stiffness, of the gastrocnemius muscle impairs ambulation in children with cerebral palsy (CP). Noninvasive measurements of passive muscle stiffness independent of both neural mediated stiffness and joint/tendon stiffness has been quite limited. Therefore, we propose to use Shear Wave Elastography (SWE), to noninvasively quantify passive muscle stiffness. SWE functions by propagating shear waves through tissue. The ultrasound measures the propagation speed of these waves and which are used to calculate tissue stiffness (Young’s Modulus). Feasibility of use of SWE in typically developing (TD) children is the first step towards quantifying muscle stiffness in children with CP. Design: Case Series. Setting: Tertiary Care Academic Medical Center. Participants: 5 year-old girl and 11 year-old boy. Interventions: With the children prone, SWE measurements of bilateral lateral gastrocnemius muscles were obtained with each foot passively positioned to 20 plantarflexion, 10 plantarflexion, 0 plantarflexion, and 10 dorsiflexion. Surface EMG was used to ensure muscle relaxation. Main Outcome Measures: Shear wave measurement of Young’s modulus (kPa) Results or Clinical Course: Young’smodulus increased as the feet were ranged fromplantarflexion to dorsiflexion in both children. For the boy,Young’smodulus (mean SD)at 20 plantarflexionwas25.6 1.9 kPa (right) and 33.1 6.7 kPa (left). For the girl, it was 19.2 1 3.8 kPa (right) and 19.5 5.0 kPa (left). At 10 dorsiflexion for the boy, it was 107.9 32.8 kPa (right) and 96.0 3.8 kPa (left). For the girl, it was 59.6 6.7 kPa (right) and 86.0 5.9 kPa (left). At all foot positions bilaterally, Young’s modulus was greater in the boy than the girl. Conclusions: SWE measurements of passive muscle stiffness of the lateral gastrocnemius in TD children appear to differ with age and gender. More studies are needed to quantify this difference, along with initiating feasibility studies in children with CP.

Poster 354: Vascular Formation as a Cause for Unilateral Toe Walking: A Case Report

benefits as their peers through accommodations. In this case requirements were extended time on tests due to hand/wrist position for writing or computer typing, availability of leaving tools in the classroom to avoid backpack straps causing neuropathies, and ability to limit activities in physical education with presence of symptoms. Establishing an appropriate 504 plan is a detailed process necessary for the success of patients with such disabilities. Conclusions: HNPP affects extracurricular and scholarly activities. There must be ongoing collaboration between the medical team, child and family, and school across a child’s developmental/social/educational transitions. Level of Evidence: Level V

Differences in Lumbar Motor Neuron Pruning in an Animal Model of Early Onset Spasticity

Motor neuron (MN) development in early onset spasticity is poorly understood. For example, spastic cerebral palsy (sCP), the most common motor disability of childhood, is poorly predicted by brain imaging, yet research remains focused on the brain. By contrast, MNs, via the motor unit and neurotransmitter signaling, are the target of most therapeutic spasticity treatments and are the final common output of motor control. MN development in sCP is a critical knowledge gap, because the late embryonic and postnatal periods are not only when the supposed brain injury occurs but also are critical times for spinal cord neuromotor development. Using an animal model of early onset spasticity [ spa mouse (B6.Cg- Glrbspa/J) with a glycine (Gly) receptor mutation], we hypothesized that removal of effective glycinergic neurotransmitter inputs to MNs during development will influence MN pruning (including primary dendrites) and MN size. Spa (Glrb-/-) and wild-type (Glrb+/+) mice, ages 4-9 wk, underwent unilateral retrograde labeling of the tibialis anterior muscle MNs via peroneal nerve dip in tetramethylrhodamine. After 3 days, mice were euthanized and perfused with 4% paraformaldehyde, and the spinal cord was excised and processed for confocal imaging. Spa mice had ~61% fewer lumbar tibialis anterior MNs ( P < 0.01), disproportionately affecting larger MNs. Additionally, a ~23% reduction in tibialis anterior MN somal surface area ( P < 0.01) and a 12% increase in primary dendrites ( P = 0.046) were observed. Thus MN pruning and MN somal surface area are abnormal in early onset spasticity. Fewer and smaller MNs may contribute to the spastic phenotype. NEW & NOTEWORTHY Motor neuron (MN) development in early onset spasticity is poorly understood. In an animal model of early onset spasticity, spa mice, we found ~61% fewer lumbar tibialis anterior MNs compared with controls. This MN loss disproportionately affected larger MNs. Thus number and heterogeneity of the MN pool are decreased in spa mice, likely contributing to the spastic phenotype.

Custom neck orthosis in combination with onabotulinumtoxinA for the treatment of refractory congenital muscular torticollis: A case report.

PURPOSE This case report examines the use of a custom neck orthosis following onabotulinumtoxinA (BoNT-A) injections for the treatment of congenital muscular torticollis (CMT) that has not been responsive to conservative treatment or previous injections. METHODS The patient was fitted for a custom neck orthosis following BoNT-A injections for refractory CMT. Clinical outcomes were evaluated with head tilt, cervical rotation, and neck passive range of motion (PROM) measurements. Parental reports of patient tolerance of the orthosis and family satisfaction of results were obtained through survey. RESULTS With use of the orthosis following BoNT-A injections, the patients head tilt improved from 45° to an intermittent tilt of 10° and neck PROM to the left improved from 70° to 90°. He wore the neck orthosis for 8 to 10 hours per day for 3 months, experienced no major complications, and tolerated it well. On follow-up survey, the family reported satisfaction with the results. CONCLUSION This case provides evidence that a custom neck orthosis after BoNT-A injection may be an effective treatment of refractory CMT before or replacing surgical intervention.