Pediatric Orthopaedics

Timing of Pavlik Harness Initiation: Can We Wait? Background: Developmental dysplasia of the hip is effectively treated with a Pavlik harness (PH) within the first 6 months of life. Over 80% of unstable hips in the newborn period will naturally stabilize by 2 months of age. If there is no difference in the effectiveness of initiating PH treatment at 1 week compared with 4 weeks of age, waiting may allow the hips to naturally stabilize and avoid treatment. The purpose of this study is to evaluate whether the timing of PH implementation influences its effectiveness in the treatment of developmental dysplasia of the hip. Methods: A retrospective review was conducted between 2004 and 2010. Patients were included if PH therapy was prescribed for hip instability or dislocation at or before 6 months of age. PH failure was defined as requiring any operative procedure for definitive management. Groups were divided based on the age at which the PH was initiated—group1=<30 days, group 2=30 to 60 days, group 3=>60 days. Results: A total of 176 children were included with 38 (21.6%) failing PH treatment. The mean age at PH initiation was 1.3 months (SD=1.3) in the successfully treated children and 1.4 months (SD=1.2) in the failures (P=0.77). There was no difference in the failure rates by age with group 1=19.1% (18/94), group 2=22.5% (9/40), and group 3=26.2% (11/42) (P=0.87). There was no statistical difference with respect to sex or breech positioning in the success or failure groups; however, there was a higher percentage of bilateral involvement in the failure group (P=0.04). Conclusions: Patients who had PH initiation before 30 days of age were no more or less likely to fail than when PH was initiated after 30 days of age. Parents can be counseled that waiting until after 30 days of age is appropriate before PH implementation. By avoiding swaddling during this period, the hips may stabilize without treatment and allow for more parental-infant bonding before implementation of PH. Level of Evidence: Level III—therapeutic, case control study.

Safe Transportation in-Spica Following Surgical Treatment of Infantile DDH: Solutions and Threats Background: Government regulations mandate appropriate vehicular restraints for children under 4 years of age. Patients treated for infantile developmental dysplasia of the hip (DDH) with spica casts often require special accommodations. Previous work suggests that car seat loaner programs may help achieve these goals while avoiding the need for costly ambulance transportation. The purpose of this study was to evaluate our center's experience with postdischarge transportation in a large population of DDH infants and identify future threats to our program. Methods: We performed a retrospective review of patients 4 years or younger of age who underwent closed or open reduction for DDH at our center between 2011 and 2018. Only the initial surgery of staged procedures was included. Patient demographic factors were recorded, as were procedure type, final restraint used for postdischarge transportation, and any potential discharge delays secondary to transportation issues. Costs were compared amongst transportation options. Results: Our cohort consisted of 130 patients (mean age, 1.4±0.9 y; 98 females) treated for DDH. In total 41 children (31.5%) underwent closed reduction procedures, whereas 89 patients (68.5%) underwent open reductions. After reduction, 62 (47.7%) received 2-legged spica casts and 68 (52.3%) received 1.5-legged casts. The most common restraint was a hospital-loaned Hippo car seat (73, 55.8%) followed by family-owned car seats (27, 20.8%). Eight patients (6.2%) experienced delays in discharge while waiting for adequate restraints, 6 patients (4.6%) were transported by ambulance, and 4 patients (3.1%) left against medical advice with inadequate restraints. Conclusions: Following surgical treatment of DDH, over 50% of patients with a spica cast were discharged using our center's car seat loaner program. However, availability and cost can present barriers for patients, with 4.6% of patients still being transported home by ambulance and 3.1% with inadequate restraints against medical advice. Costs of car seats are significant both for patients' families intending to purchase them, as well as for hospitals maintaining loaner programs and replacing used/lost seats. Moving forward, the recent cessation of production of the most common "spica car seat" threatens the longevity of existing loaner programs and calls renewed attention to the issue of safe transportation in-spica from providers and car-seat manufacturers alike. Level of Evidence: Level III.

Comparison of Surgical Outcomes Between a Triplane Proximal Femoral Osteotomy and the Modified Dunn Procedure for Stable, Moderate to Severe Slipped Capital Femoral Epiphysis Background: Recent studies have demonstrated the intra-articular cartilage and labral damage that can occur from the proximal femoral cam-like deformity of a moderate to severe slipped capital femoral epiphysis (SCFE). The approach to treating this deformity in a symptomatic Loder stable hip is controversial. The purpose of this study was to compare radiographic outcomes, complication rates, and revision rates between Imhauser type triplane proximal femoral osteotomy (TPFO) and the modified Dunn procedure (MDP). Methods: Twenty-six subjects with minimum 1-year follow-up were included (12 treated with a TPFO, and 14 treated with the MDP). A chart review was performed to capture data related to complications, revision procedures, surgical time, and body mass index. Radiographs were measured preoperatively and at final follow-up to evaluate epiphyseal-slip angle, neck-shaft angle, articular surface to trochanter distance, and medial proximal femoral angle. Results: Surgical time was shorter for the TPFO group (150.0±57.4 min) compared with the MDP group (203.8±30 min) (P=0.005). All preoperative and postoperative radiographic measures were similar between the 2 groups except postoperative neck-shaft angle, which was significantly less in the TPFO group (129.7±8.6 vs. 140.9±9.4 degrees) (P=0.005). There were no cases of femoral head avascular necrosis (AVN) in the TPFO group. The modified Dunn group had a 29% AVN rate (P=0.1). The overall complication rate was similar between the TPFO (33%) and modified Dunn (36%) groups (P=1.0) and the reoperation rate was slightly greater in the TPFO group (33%) as compared with the modified Dunn group (21%) (P=0.67). Conclusions: The complex 3-dimensional proximal femoral deformity of a moderate to severe SCFE can be difficult to treat with relatively high complication/reoperation rates observed in both TPFO and MDP groups. All 4 instances of AVN in this study of stable slips, however, were in the MDP group. As this can be a devastating complication leading to early total hip arthroplasty, we advise against the MDP in stable SCFE patients. Level of Evidence: Level III—retrospective comparative study.

Wash, Rinse, Repeat: Which Patients Undergo Serial Joint Irrigation in Pediatric Septic Hip Arthritis? Background: The purpose of this study is to identify risk factors associated with repeat surgical irrigation in pediatric septic hip arthritis. Methods: A single center retrospective case-control study was performed. Patients who underwent ≥2 washouts (cases) were compared with those who had only 1 washout (controls). Demographic, clinical, laboratory, microbial, and magnetic resonance imaging data were compared between cases and controls and a prediction model was developed using logistic regression. A risk score was then constructed by counting the number of risk factors from the model that were present in each patient. Results: We identified 26 patients between 1994 and 2015 who underwent ≥2 washouts for septic hip arthritis, and 63 control patients who had only a single washout. Twenty-two patients had 2 washouts, 3 had 4 washouts, 1 had 5 washouts. Median number of days between first and second washout was 5 (interquartile range, 4 to 8). The most common reason for repeat washout was persistent fever (N=21), followed by persistently elevated laboratory values (N=13), abnormal magnetic resonance imaging findings (N=12), and continued pain (N=12). Repeat washout cases demonstrated higher temperature preoperatively (P<0.001), had more frequent initial misdiagnosis (P=0.002), and had a longer time from symptom onset to surgery (P=0.02). Laboratory values in these cases showed higher C-reactive protein (P=0.003), and more frequent left shift (P=0.03) at presentation, with a greater proportion of positive cultures (P<0.001). Postoperatively, repeat washout cases had higher temperatures (P<0.001), more frequent wound drainage (P=0.02), and complications (P=0.001). A risk score for predicting the likelihood of undergoing repeat washout was constructed by counting the number of the following factors present: presence of left shift in CBC, positive blood or synovial fluid cultures, and postoperative temperature over 39°C. Seventy percent of cases had ≥2 of these risk factors and 80% of controls had ≤1 risk factor. Conclusions: Cases of pediatric septic arthritis which undergo repeat washout are associated with left shift, high postoperative temperatures, and positive cultures. They have more frequent misdiagnosis leading to delayed treatment and subsequent medical complications. Level of Evidence: Level III.

Idiopathic Genu Valgum and Its Association With Obesity in Children and Adolescents Background: Obesity as a cause of lower extremity deformity in children has been well established. This deformity is most often seen as tibia vara, however, at our institution we have observed more obese children and adolescents over age 7 years with excessive or progressive idiopathic genu valgum. Our hypothesis is that children with idiopathic genu valgum have high rates of obesity which impact the severity of their disease. Methods: Retrospective review of existing data was performed on 66 consecutive children/112 limbs over age 7 years with idiopathic genu valgum, seen from 2010 to 2013. Children with known metabolic or skeletal disease were excluded. Genu valgum was defined as mechanical axis in zone II or III and mechanical tibiofemoral angle ≥4 degrees on standing anteroposterior radiograph of the lower extremities. Body mass index (BMI) was calculated and classified by Center for Disease Control percentiles. Skeletal maturation was rated by closure of pelvic and peri-genu physes. Severity of genu valgum was also assessed by femoral and tibial mechanical axes and the mechanical axis deviation. Results: Mean patient age was 12.2±2.2 years. 47% of patients had BMI≥30 and 71% were categorized as obese (>95th percentile). No sex differences were identified. Skeletal maturation explained 25% of the variance in the mechanical axis deviation and 22% of the mechanical tibiofemoral angle. BMI predicted 9.8% of the tibial valgus. Because of its skewed distribution, BMI percentile was a less useful parameter for assessment. Conclusions: The 71% obesity rate found in our children with idiopathic genu valgum is significantly higher than the normal population. Higher BMI is associated with more tibial valgum but skeletal maturation was the main predictor of overall valgus severity. This suggests that obesity may play a role in the etiology of idiopathic genu valgum which progresses with skeletal maturation, thereby increasing the risk of osteoarthritis in adulthood. Level of Evidence: Level III.

Concomitant Anterior Cruciate Ligament Reconstruction and Temporary Hemiepiphysiodesis in the Skeletally Immature: A Combined Technique Background: Young athletes with an anterior cruciate ligament (ACL) disruption and limb malalignment pose a treatment dilemma. Little has been published regarding limb malalignment in this population. Our aim is to review the results of combined treatment of an ACL deficient knee and genu valgum in skeletally immature patients. Methods: A retrospective review of skeletally immature patients who underwent transphyseal ACL reconstruction and concomitant hemiepiphysiodesis between 2004 and 2015 by 1 surgeon at a single institution was performed. Included patients had at least a year of growth remaining and were followed to skeletal maturity. Patients with a diagnosis of a connective tissue disorder were excluded. Knee stability, rate of retear, the rate of mechanical axis correction, and time to full correction were determined. Results: Ninety skeletally immature patients underwent transphyseal ACL reconstruction, 8 of which met inclusion criteria. Mean time to correction of the valgus deformity was 13 months (0.4 degree/mo). No patient required additional surgeries for malalignment. All patients had improvement in knee stability. One patient had a retear of their ACL reconstruction, for a failure rate of 13%. Preoperative mechanical lateral distal femoral angle and mechanical axis deviation corrected to near-neutral alignment for all treated limbs and were significantly different (P=0.001) than those measured preoperatively. Conclusions: Promising results were seen for simultaneous correction of genu valgum and transphyseal ACL reconstruction. Treatment of both pathologies in a concomitant surgery can be considered in the appropriate population, with expected results comparable to each procedure in isolation. Level of Evidence: Level IV—case series.

Rebound Deformity After Growth Modulation in Patients With Coronal Plane Angular Deformities About the Knee: Who Gets It and How Much? Background: With observed success and increased popularity of growth modulation techniques, there has been a trend toward use in progressively younger patients. Younger age at growth modulation increases the likelihood of complete deformity correction and need for implant removal before skeletal maturity introducing the risk of rebound deformity. The purpose of this study was to quantify magnitude and identify risk factors for rebound deformity after growth modulation. Methods: We performed a retrospective review of all patients undergoing growth modulation with a tension band plate for coronal plane deformity about the knee with subsequent implant removal. Exclusion criteria included completion epiphysiodesis or osteotomy at implant removal, ongoing growth modulation, and <1 year radiographic follow-up without rebound deformity. Mechanical lateral distal femoral angle, mechanical medial proximal tibial angle, hip-knee-ankle angle (HKA), and mechanical axis station were measured before growth modulation, before implant removal, and at final follow-up. Results: In total, 67 limbs in 45 patients met the inclusion criteria. Mean age at growth modulation was 9.8 years (range, 3.4 to 15.4 y) and mean age at implant removal was 11.4 years (range, 5.3 to 16.4 y). Mean change in HKA after implant removal was 6.9 degrees (range, 0 to 23 degrees). In total, 52% of patients had >5 degrees rebound and 30% had >10 degrees rebound in HKA after implant removal. Females below 10 years and males below 12 years at time of growth modulation had greater mean change in HKA after implant removal compared with older patients (8.4 vs. 4.7 degrees, P=0.012). Patients with initial deformity >20 degrees had an increased frequency of rebound >10 degrees compared with patients with less severe initial deformity (78% vs. 22%, P=0.002). Conclusions: Rebound deformity after growth modulation is common. Growth modulation at a young age and large initial deformity increases risk of rebound. However, rebound does not occur in all at risk patients, therefore, we recommend against routine overcorrection. Level of Evidence: Level IV—retrospective study.

Growth-Friendly Spine Surgery in Escobar Syndrome Background: The aims of this study were to characterize the spinal deformity of patients with Escobar syndrome, describe results of growth-friendly treatments, and compare these results with those of an idiopathic early-onset scoliosis (EOS) cohort to determine whether the axial stiffness in Escobar syndrome limited correction. Methods: We used 2 multicenter databases to review the records of 8 patients with EOS associated with Escobar syndrome who had at least 2-year follow-up after initiation of growth-friendly treatment from 1990 to 2016. An idiopathic EOS cohort of 16 patients matched for age at surgery (±1 y), postoperative follow-up (±1 y), and initial curve magnitude (±10 degrees) was identified. A randomized 1:2 matching algorithm was applied (α=0.05). Results: In the Escobar group, spinal deformity involved 7 to 13 vertebrae and ranged from no vertebral anomalies in 3 patients to multiple segmentation defects in 6 patients. Mean age at first surgery was 5 years (range, 1.4 to 7.8 y) with a mean follow-up of 7.5 years (range, 4.0 to 10 y). Mean major curve improved from 76 degrees at initial presentation, to 43 degrees at first instrumentation, to 37 degrees at final follow-up (both P<0.001). Mean pelvic obliquity improved from 16 degrees (range, 5 to 31 degrees) preoperatively to 4 degrees (range, 0 to 8 degrees) at final follow-up (P=0.005). There were no differences in the mean percentage of major curve correction between the idiopathic EOS and Escobar groups at the immediate postoperative visit (P=0.743) or final follow-up (P=0.511). There were no differences between the cohorts in T1-S1 height at initial presentation (P=0.129) or in growth per month (P=0.211). Conclusions: Multiple congenital fusions and spinal curve deformity are common in Escobar syndrome. Despite large areas of congenital fusion, growth-friendly constructs facilitate spinal growth and improve curve correction. These results are comparable to those in idiopathic EOS. Level of Evidence: Level III—case-control study.

Common Elements in Surgical Site Infection Care Bundles for Adolescent Idiopathic Scoliosis at North American Pediatric Institutions: A Survey of POSNA QSVI Challenge Participants Background: Surgical site infection (SSI) following posterior spinal fusion for idiopathic scoliosis is a difficult complication, with little information published regarding the best preventative comprehensive care plan. The Spine Subgroup of the Quality, Safety, Value Initiative (QSVI) committee of the Pediatric Orthopaedic Society of North America undertook a survey to generate an overview of bundle elements in comprehensive SSI care bundles across institutions in North America. The purpose of this study was to develop a toolkit of SSI care bundle elements that could be used in developing future SSI care bundles. Methods: A survey email was sent to pediatric orthopaedic surgeons requesting a copy of the SSI prevention care bundle used in their practice. Surgeons were included if they had participated in the 2016 POSNA QSVI challenge, indicated they performed pediatric spine surgery, and had a spine SSI bundle. These bundles were evaluated by the QSVI committee and divided into preoperative, intraoperative, and postoperative elements with the frequency of use of each element recorded. A follow-up qualitative questionnaire was sent assessing the implementation and development of these SSI bundles. Results: In total, 16 care bundles from 15 different institutions were included for review. The response rate for this survey was 44% of individuals (50/113 QSVI challenge participants) and 43% (15/35) of unique institutions. The most common elements included: use of preoperative antibiotics, use of preoperative chlorhexidine wipes, use of wound irrigation intraoperatively, and a standardized prescription for the length of postoperative antibiotic. Each of these elements was included in ≥75% of the SSI bundles evaluated. Conclusions: SSI care bundles are increasingly being used by pediatric institutions to lower the risk of SSI following pediatric spinal surgery. This study provides an overview of various care elements used in established SSI care bundles across multiple institutions in North America. It is hoped this data will provide institutions interested in developing their own SSI care bundle with useful information for beginning this process. Level of Evidence: Level V—Decision Analysis.

The Role of Computed Tomography and Magnetic Resonance Imaging in the Diagnosis of Pediatric Thoracolumbar Compression Fractures Background: Because of concerns about radiation exposure, some centers consider magnetic resonance imaging (MRIs) the preferred imaging modality for pediatric thoracic and/or lumbar compression fractures. The purpose of this study was to evaluate the sensitivity of computed tomography (CT) and MRI in diagnosing thoracolumbar compression fractures and the utility of MRI in their management. Methods: Retrospective review identified 52 patients aged 0 to 18 years with 191 thoracic and/or lumbar compression fractures who had both CT and MRI during the initial trauma evaluation. The decision to perform CT and/or MRI was made by the attending pediatric spine surgeon. In all cases the CT scan was performed before the MRI. All imaging studies were reviewed by a board-certified pediatric radiologist and attending pediatric spine surgeon. Results: Only 10 patients (19%) had a single-level injury. Of 42 with multiple compression fractures, 34 (81%) had fractures in contiguous levels, and 8 had noncontiguous injuries. Comparing CT and MRI, there was complete agreement in the number and distribution of fractures in 23 patients (44%). MRI identified additional levels of fracture in 15 patients (29%); 14 (27%) had fewer levels fractured on MRI than CT. Only one patient (2%) had fractures seen on MRI after a normal CT scan. Complete correlation between CT and MRI was seen in 59% (17/29) of patients aged 11 to 18 years, compared with 26% (6/23) of patients younger than 11. Conclusions: In pediatric patients with mild thoracic or lumbar compression fracture(s), CT scan demonstrates a high sensitivity in determining the presence or absence of a fracture compared with MRI. Although some variability exists between the 2 modalities in the exact number of spinal levels involved, the definitive treatment and outcome were not changed by the addition of MRI. The information that may be obtained from an MRI must be weighed against the increased time and expense of the study, as well as the risks associated with sedation when necessary. Level of Evidence: Level II—diagnostic study.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com

Head Trauma Rehabilitation

Estimated Life-Time Savings in the Cost of Ongoing Care Following Specialist Rehabilitation for Severe Traumatic Brain Injury in the United Kingdom Objectives: To evaluate cost-efficiency of rehabilitation following severe traumatic brain injury (TBI) and estimate the life-time savings in costs of care. Setting/Participants: TBI patients (n = 3578/6043) admitted to all 75 specialist rehabilitation services in England 2010–2018. Design: A multicenter cohort analysis of prospectively collated clinical data from the UK Rehabilitation Outcomes Collaborative national clinical database. Main Measures: Primary outcomes: (a) reduction in dependency (UK Functional Assessment Measure), (b) cost-efficiency, measured in time taken to offset rehabilitation costs by savings in costs of ongoing care estimated by the Northwick Park Dependency Scale/Care Needs Assessment (NPDS/NPCNA), and (c) estimated life-time savings. Results: The mean age was 49 years (74% males). Including patients who remained in persistent vegetative state on discharge, the mean episode cost of rehabilitation was £42 894 (95% CI: £41 512, £44 235), which was offset within 18.2 months by NPCNA-estimated savings in ongoing care costs. The mean period life expectancy adjusted for TBI severity was 21.6 years, giving mean net life-time savings in care costs of £679 776/patient (95% CI: £635 972, £722 786). Conclusions: Specialist rehabilitation proved highly cost-efficient for severely disabled patients with TBI, despite their reduced life-span, potentially generating over £4 billion savings in the cost of ongoing care for this 8-year national cohort.

Strengthening the Evidence Base: Recommendations for Future Research Identified Through the Development of CDC's Pediatric Mild TBI Guideline Objective: The recently published Centers for Disease Control and Prevention evidence-based guideline on pediatric mild traumatic brain injury (mTBI) was developed following an extensive review of the scientific literature. Through this review, experts identified limitations in existing pediatric mTBI research related to study setting and generalizability, mechanism of injury and age of cohorts studied, choice of control groups, confounding, measurement issues, reporting of results, and specific study design considerations. This report summarizes those limitations and provides a framework for optimizing the future quality of research conduct and reporting. Results: Specific recommendations are provided related to diagnostic accuracy, population screening, prognostic accuracy, and therapeutic interventions. Conclusion: Incorporation of the recommended approaches will increase the yield of eligible research for inclusion in future systematic reviews and guidelines for pediatric mTBI.

Comorbid Conditions Among Adults 50 Years and Older With Traumatic Brain Injury: Examining Associations With Demographics, Healthcare Utilization, Institutionalization, and 1-Year Outcomes Objectives: To assess the relationship of acute complications, preexisting chronic diseases, and substance abuse with clinical and functional outcomes among adults 50 years and older with moderate-to-severe traumatic brain injury (TBI). Design: Prospective cohort study. Participants: Adults 50 years and older with moderate-to-severe TBI (n = 2134). Measures: Clusters of comorbid health conditions empirically derived from non-injury International Classification of Diseases, Ninth Revision codes, demographic/injury variables, and outcome (acute and rehabilitation length of stay [LOS], Functional Independence Measure efficiency, posttraumatic amnesia [PTA] duration, institutionalization, rehospitalization, and Glasgow Outcome Scale–Extended (GOS-E) at 1 year). Results: Individuals with greater acute hospital complication burden were more often middle-aged men, injured in motor vehicle accidents, and had longer LOS and PTA. These same individuals experienced higher rates of 1-year rehospitalization and greater odds of unfavorable GOS-E scores at 1 year. Those with greater chronic disease burden were more likely to be rehospitalized at 1 year. Individuals with more substance abuse burden were most often younger (eg, middle adulthood), black race, less educated, injured via motor vehicle accidents, and had an increased risk for institutionalization. Conclusion: Preexisting health conditions and acute complications contribute to TBI outcomes. This work provides a foundation to explore effects of comorbidity prevention and management on TBI recovery in older adults.

The Contribution of Social Support, Professional Support, and Financial Hardship to Family Caregiver Life Satisfaction After Traumatic Brain Injury Objectives: (a) To assess whether 3 changeable environmental variables (social support, professional support, and financial hardship) contribute to explaining differences in well-being of family caregivers after traumatic brain injury (TBI), above and beyond the influence of neurobehavioral functioning. (b) To assess the unique and relative contribution of social support, professional support, and financial hardship to life satisfaction of family caregivers. Participants: Adult family caregivers (n = 136) of individuals who received inpatient rehabilitation following a TBI. Measures: The Social Provisions Scale; Brief Scale of Financial Hardship after Brain Injury; Satisfaction with Life Scale; and adapted scales measuring professional support and neurobehavioral functioning. Design: Cross-sectional study using survey methodology. Results: Social support, professional support, and financial hardship explained a significant amount of variance in life satisfaction after controlling for neurobehavioral functioning (R2 change = 0.34, considered a large effect size). Social support and financial hardship were significant unique predictors within the model, but professional support was not. Conclusion: Social support and financial hardship are prominent environmental variables that may hold promise for targeted intervention development and testing designed to support family adaptation after TBI.

A Systematic Review of Sleep-Wake Disturbances in Childhood Traumatic Brain Injury: Relationship with Fatigue, Depression, and Quality of Life Objective: To systematically appraise the literature on the prevalence, types, and predictors of sleep-wake disturbances (SWD), and on the relationship between SWD, fatigue, depression, and quality of life in children and adolescents with traumatic brain injury (TBI). Methods: MEDLINE, PubMed, PsychInfo, Web of Science, and EMBASE databases were searched, reference lists of retrieved articles were also searched for relevant articles, and study methods were evaluated for risk of bias. Results: Of the 620 articles assessed, 16 met inclusion criteria. Sleep-wake disturbances were common in childhood TBI. The most common types of SWD reported were insomnia and excessive daytime sleepiness, with mild TBI participants showing a trend toward more sleep maintenance insomnia, while sleep-onset insomnia was typical in those with moderate-severe TBI. Predictors of SWD reported in studies involving mild TBI participants included TBI severity, male sex, preexisting SWD, high body weight, and depression; while injury severity and internalizing problems were associated with SWD in moderate-severe TBI participants. Sleep-wake disturbances were also associated with fatigue and poor quality of life following TBI. Conclusion: Sleep-wake disturbances are highly prevalent in childhood TBI, regardless of injury severity. Routine assessments of SWD in survivors of childhood TBI are recommended.

Healthcare Utilization and Missed Workdays for Parents of Children With Traumatic Brain Injury Background: We enrolled patients in a prospective study in which we obtained estimates of the direct and indirect burden for families of children with traumatic brain injury (TBI) relative to a control group of families of children with orthopedic injury (OI). Methods: Parents were surveyed at 3 time points following injury: 3, 6, and 12 months. At each follow-up contact, we asked parents to list the number of workdays missed, number of miles traveled, amount of travel-related costs, and whether their child had an emergency department (ED) visit, hospital admission, any over-the-counter (OTC) medications, and any prescription medications during that time period. We assessed the difference in these outcomes between the TBI and OI groups using multivariable logistic and 2-part regression models to account for high concentrations of zero values. Results: Children with TBI had significantly greater odds of having an ED visit (3.04; 95% CI, 1.12-8.24), OTC medications (1.98; 95% CI, 1.34-2.94), and prescription medications (2.34; 95% CI, 1.19-4.59) than those with OI. In addition, parents of children with TBI missed significantly more days of work (19.91 days; 95% CI, 11.64-28.17) overall during the 12 months following injury than their OI counterparts. Conclusion: Extrapolating our results to the entire country, we estimate that pediatric TBI is associated with more than 670 000 lost workdays annually over the 12 months following injury, which translates into more than $150 million in lost productivity. These missed workdays and lost productivity may be prevented through safety efforts to reduce pediatric TBI.

Protocol for a Randomized Controlled Trial of CI Therapy for Rehabilitation of Upper Extremity Motor Deficit: The Bringing Rehabilitation to American Veterans Everywhere Project Constraint-induced movement therapy (CI therapy) has been shown to reduce disability for individuals with upper extremity (UE) hemiparesis following different neurologic injuries. This article describes the study design and methodological considerations of the Bringing Rehabilitation to American Veterans Everywhere (BRAVE) Project, a randomized controlled trial of CI therapy to improve the motor deficit of participants with chronic and subacute traumatic brain injury. Our CI therapy protocol comprises 4 major components: (1) intensive training of the more-affected UE for target of 3 hour/day for 10 consecutive weekdays, (2) a behavioral technique termed shaping during training, (3) a "transfer package," 0.5 hour/day, of behavioral techniques to transfer therapeutic gains from the treatment setting to the life situation, and (4) prolonged restraint of use of the UE not being trained. The primary endpoint is posttreatment change on the Motor Activity Log, which assesses the use of the more-affected arm outside the laboratory in everyday life situations. Data from a number of secondary outcome measures are also being collected and can be categorized as physical, genomic, biologic, fitness, cognitive/behavioral, quality of life, and neuroimaging measures.

Prevalence of Medical and Psychiatric Comorbidities Following Traumatic Brain Injury Objective: To examine the prevalence of selected medical and psychiatric comorbidities that existed prior to or up to 10 years following traumatic brain injury (TBI) requiring acute rehabilitation. Design: Retrospective cohort. Setting: Six TBI Model Systems (TBIMS) centers. Participants: In total, 404 participants in the TBIMS National Database who experienced TBI 10 years prior. Interventions: Not applicable. Main Outcome Measure: Self-reported medical and psychiatric comorbidities and the onset time of each endorsed comorbidity. Results: At 10 years postinjury, the most common comorbidities developing postinjury, in order, were back pain, depression, hypertension, anxiety, fractures, high blood cholesterol, sleep disorders, panic attacks, osteoarthritis, and diabetes. Comparing those 50 years and older to those younger than 50 years, diabetes (odds ratio [OR] = 3.54; P = .0016), high blood cholesterol (OR = 2.04; P = .0092), osteoarthritis (OR = 2.02; P = .0454), and hypertension (OR = 1.84; P = .0175) were significantly more prevalent in the older cohort while panic attacks (OR = 0.33; P = .0022) were significantly more prevalent in the younger cohort. No significant differences in prevalence rates between the older and younger cohorts were found for back pain, depression, anxiety, fractures, or sleep disorders. Conclusions: People with moderate-severe TBI experience other medical and mental health comorbidities during the long-term course of recovery and life after injury. The findings can inform further investigation into comorbidities associated with TBI and the role of medical care, surveillance, prevention, lifestyle, and healthy behaviors in potentially modifying their presence and/or prevalence over the life span.

Factors Influencing Primary Care Follow-Up After Pediatric Mild Traumatic Brain Injury Objective: To identify socioeconomic, demographic, and caregiver factors associated with children attending primary care provider (PCP) follow-up after emergency department (ED) evaluation for mild traumatic brain injury (mTBI). Setting: Pediatric trauma center ED. Participants: Children 8 to 18 years of age sustaining mTBI less than 48 hours prior to an ED visit. Mean age of the 183 participants was 12 years with no significant differences between those who attended follow-up and those who did not in race, ethnicity, insurance provider, or PCP office setting. Design: Thirty-day longitudinal cohort study. Main Measures: Insurance type, PCP practice setting, and a caregiver attitudes survey regarding mTBI recovery and management (5 questions each scored on a 5-point Likert scale). The primary outcome was attending a PCP follow-up visit within 1 month of injury. Results: Females were more likely than males to attend PCP follow-up (adjusted odds ratio: 2.27 [95% confidence interval: 1.00-5.18]). Increasing scores on the caregiver attitudes survey indicating greater concerns about recovery were significantly associated with attending PCP follow-up (adjusted odds ratio: 1.12 per unit increase in composite score [95% confidence interval: 1.02-1.23]). No other socioeconomic, demographic, or injury characteristics were associated with attending PCP follow-up. Conclusions: The ED counseling regarding PCP follow-up of mTBI should stress the importance of follow-up care to monitor recovery and identify presence of lingering symptoms.

Performance Validity in Collegiate Football Athletes at Baseline Neurocognitive Testing Objective: To assess the prevalence of invalid performance on baseline neurocognitive testing using embedded measures within computerized tests and individually administered neuropsychological measures, and to examine the influence of incentive status and performance validity on neuropsychological test scores. Setting: Sport-related concussion management program at a regionally accredited university. Participants: A total of 83 collegiate football athletes completing their preseason baseline assessment within the University's concussion management program and a control group of 140 nonathlete students. Design: Cross-sectional design based on differential incentive status: motivated to do poorly to return to play more quickly after sustaining a concussion (athletes) versus motivated to do well due to incentivizing performance (students). Main Measures: Immediate Post-Concussion and Cognitive Testing (ImPACT), performance validity tests, and measures of cognitive ability. Results: Half of the athletes failed at least 1 embedded validity indicator within ImPACT (51.8%), and the traditional neuropsychological tests (49.4%), with large effects for performance validity on cognitive test scores (d: 0.62-1.35), incentive status (athletes vs students; d: 0.36-1.15), and the combination of both factors (d: 1.07-2.20) on measures of attention and processing speed. Conclusion: Invalid performance on baseline assessment is common (50%), consistent across instruments (ImPACT or neuropsychological tests) and settings (one-on-one or group administration), increases as a function of incentive status (risk ratios: 1.3-4.0) and results in gross underestimates of the athletes' true ability level, complicating the clinical interpretation of the postinjury evaluation and potentially leading to premature return to play.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com

Spine

"Sailboats in Boothbay, Maine" No abstract available

Mechanical Function of the Nucleus Pulposus of the Intervertebral Disc Under High Rates of Loading Study Design. Bovine motion segments were used to investigate the high-rate compression response of intervertebral discs (IVD) before and after depressurising the nucleus pulposus (NP) by drilling a hole through the cranial endplate into it. Objective. To investigate the effect of depressurising the NP on the force–displacement response, and the energy absorption in IVDs when compressed at high strain rates. Summary of Background Data. The mechanical function of the gelatinous NP located in the center of the IVDs of the spine is unclear. Removal of the NP has been shown to affect the direction of bulge of the inner anulus fibrosus (AF), but at low loading rates removal of the NP pressure does not affect the IVD's stiffness. During sports or injurious events, IVDs are commonly exposed to high loading rates, however, no studies have investigated the mechanical function of the NP at these rates. Methods. Eight bovine motion segments were used to quantify the change in pressure caused by a hole drilled through the cranial endplate into the NP, and eight segments were used to investigate the high-rate response before and after a hole was drilled into the NP. Results. The hole caused a 28.5% drop in the NP pressure. No statistically significant difference was seen in peak force, peak displacement, or energy-absorption of the intact, and depressurized NP groups under impact loading. The IVDs absorbed 72% of the input energy, and there was no rate dependency in the percentage energy absorbed. Conclusion. These results demonstrate that the NP pressure does not affect the transfer of load through, or energy absorbed by, the IVD at high loading rates and the AF, rather than the NP, may play the most important role in transferring load, and absorbing energy at these rates. This should be considered when attempting surgically to restore IVD function. Level of Evidence: N/A

Locally Applied Simvastatin as an Adjunct to Promote Spinal Fusion in Rats Study Design. Basic Science. Objective. To determine if locally delivered simvastatin can enhance bone formation in a rat spinal fusion model. Summary of Background Data. The bone-anabolic properties of statins in fracture healing are well established, however, few studies have evaluated the impact of locally delivered statins in spinal fusion. Methods. We formulated poly(lactic-co-glycolic acid) (PLGA) nanoparticles by adapting previously published techniques. Two types of nanoparticles were created: simvastatin nanoparticles (SimNP) and nanoparticles without simvastatin (BlankNP). Drug elution from SimNP was characterized. Osteoblastic differentiation was analyzed using MC3T3-E1 cells cultured in differentiation medium containing SimNP or BlankNP. Forty male 12 week old outbred Wistar rats underwent uninstrumented posterolateral fusion using iliac crest bone graft and BlankNP, SimNP or simvastatin drug. X-rays to assess bone formation were obtained at 4 weeks and 9 weeks post-operatively. Spines were explanted at 9 weeks for micro-CT analysis, and a blinded manual assessment of fusion (MAF). Results. SimNP achieved a release efficiency of 74.1% with ∼50% release occurring in the first day. Simvastatin and SimNP treated cells showed significantly greater expression of osteopontin (OPN) and osteocalcin (OCN). On micro-CT analysis, SimNP animals had higher bone volume and percent bone volume (bone volume/total volume) than control animals. SimNP rats had higher X-ray scores at 4 weeks (p=0.010) and 9 weeks (p<0.001) relative to BlankNP. MAF showed that SimNP had a higher fusion rate than BlankNP (42.9% vs. 0%, p=0.006). Conclusion. We were able to validate that sustained release of simvastatin via a PLGA nanoparticle. SimNP was able to induce an increase in mineralization as well as an increase in markers of bone formation. X-ray analysis, micro-CT quantification, and MAF assessment of SimNP treated rats showed significantly greater bone formation and fusion mass strength relative to vehicle treated animals. Simvastatin may be a safe, cost-effective bone anabolic agent for use in spinal fusion. Level of Evidence. N/A

AMP-Activated Protein Kinase Activation in Dorsal Root Ganglion Suppresses mTOR/p70S6K Signaling and Alleviates Painful Radiculopathies in Lumbar Disc Herniation Rat Model Study Design. Animal experiment: a rat model of lumbar disc herniation (LDH) induced painful radiculopathies. Objective. To investigate the role and mechanism of AMP-activated protein kinase (AMPK) in dorsal root ganglia (DRG) neurons in LDH-induced painful radiculopathies. Summary of Background Data. Overactivation of multiple pain signals in DRG neurons triggered by LDH is crucial to the development of radicular pain. AMPK is recognized as a cellular energy sensor, as well as a pain sensation modulator, but its function in LDH-induced pain hypersensitivity remains largely unknown. Methods. The LDH rat model was established by autologous nucleus pulposus transplantation into the right lumbar 5 (L5) nerve root. At different time points after AMPK agonist metformin (250 mg/kg/d) or mammalian target of rapamycin (mTOR) inhibitor rapamycin (5 mg/kg) intraperitoneal administration, thermal and mechanical sensitivity were evaluated by measuring paw withdrawal latency (PWL) and 50% paw withdrawal thresholds (PWT). The levels of AMPK, mTOR, and p70S6K phosphorylation were determined by Western blot. We also investigated the proportion of p-AMPK positive neurons in the right L5 DRG neurons using immunofluorescence. Results. LDH evoked persistent thermal hyperalgesia and mechanical allodynia on the ipsilateral paw, as indicated by the decreased PWL and 50% PWT. These pain hypersensitive behaviors were accompanied with significant inhibition of AMPK and activation of mTOR in the associated DRG neurons. Pharmacological activation of AMPK in the DRG neurons not only suppressed mTOR/p70S6K signaling, but also alleviated LDH-induced pain hypersensitive behaviors. Conclusion. We provide a molecular mechanism for the activation of pain signals based on AMPK-mTOR axis, as well as an intervention strategy by targeting AMPK-mTOR axis in LDH-induced painful radiculopathies. Level of Evidence: N/A

ERRFI1 Inhibits Proliferation and Inflammation of Nucleus Pulposus and Is Negatively Regulated by miR-2355-5p in Intervertebral Disc Degeneration Study Design. In vivo and in vitro studies of the role of miR-2355-5p and its possible targets in intervertebral disc degeneration (IVDD). Objective. To elucidate the regulatory role of miR-2355-5p in IVDD and the underlying mechanisms. Summary of Background Data. IVDD, which is caused by multiple factors, is the main cause of lower back pain with or without extremity pain. However, the underlying cellular mechanisms of IVDD pathogenesis are not well elucidated. Cell hyper-proliferation, inflammation, and epidermal growth factor receptor activation have been implicated in IVDD. Up-regulated miR-2355-5p level was identified to associate with IVDD. ERRFI1 (the product of mitogen-inducible gene 6 [MIG6]) was known to inhibit epidermal growth factor receptor activation. Methods. We monitored the expression of miR-2355-5p and ERRFI1 in IVDD tissues and lipopolysaccharides (LPS)-treated nucleus pulposus (NP) cells. We explored the effects of ERFFI1 on NP cells proliferation and LPS-induced pro-inflammatory cytokines production. We searched the targets of miR-2355-5p and explored the effects of miR-2355-5p on NP cells proliferation and cytokines production. Results. We identified the up-regulation of miR-2355-5p and down-regulation of ERFFI1 in IVDD samples and LPS-treated NP cells. ERFFI1 inhibited NP cells proliferation and LPS-induced pro-inflammatory cytokine production. MiR-2355-5p targeted ERFFI1 and negatively regulated ERFFI1 expression. MiR-2355-5p regulated IVDD by targeting ERFFI1. Conclusion. MiR-2355-5p negatively regulated ERFFI1 and prevented the effects of ERRFI1 on inhibiting NP cells proliferation and inflammation. Level of Evidence: N/A

Prevalence and Predictive Factors of Concurrent Cervical Spinal Cord Compression in Adult Spinal Deformity Study Design. Retrospective cross-sectional cohort. Objective. To investigate the prevalence and predictive factors of concurrent cervical spinal cord compression (CSCC) in patients with adult spinal deformity (ASD). Summary of Background Data. In patients with ASD undergoing major thoracolumbar realignment surgery, concurrent CSCC potentially increases the risk of progression of myelopathy or cervical cord injury due to various perioperative factors including poor intraoperative neck positioning and hypotension. However, the prevalence of CSCC in ASD patients has not been previously studied. Methods. This study included ASD patients who were indicated for major thoracolumbar corrective surgery (>5 levels). The presence of CSCC was determined using the modified Cord Compression Index (Grades 0–3) based on the cervical magnetic resonance imaging (MRI). Significant CSCC was defined as Grade>2, and the distribution of compression level as well as the number of Grade>2 segments were investigated in each patient. A multivariate regression analysis was performed to identify the predictors of CSCC with variables being the patients' characteristics including radiographic sagittal alignment parameters. Results. Of 121 patients with ASD, 41 patients (33.8%) demonstrated significant CSCC on MRI. Intramedullary T2 hyper-intensity (myelomalacia) was present in eight patients (6.6%). Thirty-five of 41 patients were asymptomatic or with myelopathy that is difficult to detect. Significant CSCC was most commonly observed at C4/5 level. Four patients (3.3%) underwent cervical decompression and fusion prior to thoracolumbar reconstruction. Multivariate regression analysis revealed old age, increased body mass index (BMI), and PI-LL mismatch independently predicted the CSCC grade. Conclusion. The prevalence of concurrent significant cervical cord compression in patients with ASD is relatively high at 33.8%. Preoperative evaluation of cervical MRI and examinations for signs/symptoms of myelopathy are essential for patients with (1) older age, (2) increased BMI, and (3) high PI-LL mismatch to avoid progressive myelopathy or cord injury during ASD surgery. Level of Evidence: 4

Sagittal Alignment Outcomes in Lordotic Cervical Spine: Does Three-Level Anterior Cervical Discectomy and Fusion Outperform Laminoplasty? Study Design. A prospective cohort study. Objective. To compare the radiological outcomes between three-level anterior cervical discectomy and fusion (ACDF) and plate-only open-door laminoplasty (LAMP) in patients with lordotic cervical spine. Summary of Background Data. Both three-level ACDF and LAMP are important surgical methods for multilevel cervical spondylotic myelopathy, but the cervical sagittal alignment outcomes and the lordosis preserving abilities between the two specific approaches have not been carefully compared. Methods. Sixty patients, all of whom had lordotic cervical spines and underwent three-level ACDF (n = 22) or LAMP (n = 38) for the treatment of multilevel cervical spondylotic myelopathy, were prospectively studied. Upright neutral cervical lateral radiographs were assessed preoperatively, at 3 days after surgery, and at the last follow-up (1.5 years). The primary radiological outcomes are C2–7 Cobb angle, and the secondary outcomes include C2–7 sagittal vertical axis , disc height, Harrison angle, and Ishihara index. The relationship between preoperative parameters and follow-up outcomes were assessed. Results. Preoperative cervical sagittal alignment parameters were similar between the two groups. Patients in the ACDF group obtained larger C2–7 Cobb angles than those the LAMP group early after surgery. However, the lordosis in the ACDF group decreased significantly during follow-up, leading to similar outcomes between the two groups. The lordosis-preserving ability of ACDF is significantly poorer than that of LAMP. Secondary radiological parameters also showed similar trends. In both groups, the preoperated Ishihara index was significantly related to follow-up C2–7 Cobb angles. For patients with Ishihara index less than 20, ACDF is more likely to produce a larger C2–7 Cobb angled at the time of follow-up. Conclusion. In patients with lordotic cervical spine, the sagittal alignment outcomes of the two approaches were similar, and the lordosis-preserving ability was poorer in ACDF. Further research should focus on the factors related to the lordosis-preserving ability of multilevel ACDF. Level of Evidence: 3

Pain Intensity and Fear Avoidance Explain Disability Related to Chronic Low Back Pain in a Saudi Arabian Population Study Design. A cross-sectional study. Objective. The aim of this study was to describe multi-dimensional profiles for people with chronic low back pain (CLBP) and to examine the associations between CLBP-related disability and individual, psychosocial and physical factors in a Saudi population. Summary of Background Data. CLBP-related disability is a multidimensional phenomenon. There is growing interest in exploring factors associated with CLBP-related disability in Saudi Arabia but research is limited in comparison to other countries. Methods. Participants completed questionnaires covering demographics, pain intensity, back beliefs, fear avoidance, psychological distress, and physical activity. Oswestry Disability Index (ODI) was used to measure disability. Participants also performed a standardized sequence of physical performance tests and a Pain Behavior Scale was used to evaluate pain behaviors during performance of these tests. The relationships between disability and all variables were explored using univariate and multivariate regression analyses. Results. One hundred and fifteen participants were included, 63% of whom were female. Participants demonstrated moderate disability (mean [SD]: 26.6 [13.5]). The mean (SD) back beliefs score was 28.6 (7.3). Mean depression, anxiety, and stress (DASS 21) scores indicated mild distress; however, 26% to 39% scored in the moderate to severe range for at least one subscale. In univariate analyses, pain intensity and fear avoidance beliefs (physical activity and work) were moderately associated with disability (r = 0.56, 0.49, 0.52, respectively, P < 0.001), with all other factors demonstrating weak association. Multivariate regression revealed that pain intensity, fear avoidance beliefs, psychological distress, and participants' age were all found to be associated with disability, accounting for 52.9% (adjusted R2 = 0.529) of variability. Conclusion. This study provides a unique insight into the clinical profile of people with CLBP in a Saudi Arabian population. Pain and psychosocial factors were significantly associated with disability. This study supports the contention that CLBP-related disability is a multifactorial biopsychosocial condition across different cultures. Level of Evidence: 3

Scoliosis and Cardiopulmonary Outcomes in Osteogenesis Imperfecta Patients Study Design. Retrospective clinical study of individuals with osteogenesis imperfecta (OI). Objective. To assess the relationship between severity of scoliosis and pulmonary function, and to assess the relationship between restrictive lung disease and self-reported quality of life in individuals with OI. Summary of Background Data. OI is a heritable connective tissue disorder characterized by osteopenia and a predisposition to fracture. Respiratory insufficiency is a leading cause of mortality. Literature on pulmonary function in this population has shown a negative correlation between percent-predicted vital capacity and severity of scoliosis. However, it has been suggested that decreased pulmonary function in OI may be due to intrinsic pulmonary disease, in addition to the impact of vertebral compression fractures and scoliosis. Methods. Anterior-posterior spine radiographs and pulmonary function tests from 30 individuals with OI were reviewed. Radiographs were evaluated for scoliosis, defined as a curve ≥ 10°. If more than one curve was present, the largest curve was used. Pulmonary function was defined as the forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio. Restrictive pulmonary disease was defined as FEV1/FVC > 80%, while obstructive disease was defined as FEV1/FVC < 70%. Bivariate correlation analysis was performed, using Spearman rho correlation coefficient (P < 0.05). Quality of life was assessed by SF-36. Results. The mean age was 27.6 years (range: 12–42 yrs). 57.6% were female. OI type IV was the most common (46.7%), followed by OI type III (33.3%), OI type I (10%), OI type IX (6.67% each), and OI type VIII (3.33%). Pulmonary comorbidity was present in 40% of individuals, while 6.67% had a cardiac comorbidity. The correlation between scoliosis and pulmonary function was weak and not significant (R = −0.059, P = 0.747). Conclusion. Pulmonary function is not significantly correlated with scoliosis, supporting the hypothesis that decreased pulmonary function is intrinsic to OI and/or chest wall deformities, rather than secondary to scoliosis. Level of Evidence: 4

The Change in Sway and Neuromuscular Activity in Adult Degenerative Scoliosis Patients Pre and Post Surgery Compared With Controls Study Design. Prospective cohort study. Objective. The purpose of this study is to quantify the extent of change in sway associated with maintaining a balanced posture within the cone of economy (CoE), in a group of adult degenerative scoliosis (ADS) patients' pre and postsurgery and compare them to matched non-scoliotic controls. Summary of Background Data. Patients with spinal deformities adopt a variety of postural changes in the spine, pelvis, and lower extremities in their effort to compensate for the anterior shift in the gravity line. ADS patients are known to exhibit an increased sway within their CoE. Greater sway expends more energy while standing when compared with healthy controls. Spinal alignment surgery has been shown to improve sagittal vertical axis and balance. Methods. Thirty-three ADS patients and performed a series of functional balance tests a week before and 3 months after surgery along with 20 non-scoliotic control. Results. ADS patients demonstrated more initial CoM (P = 0.001) and head (P = 0.011) displacements. Postoperatively ADS patients exhibited less CoM sway (P = 0.043) and head sway (P = 0.050), in comparison to their presurgery measures. Postsurgical ADS patients demonstrated more CoM (P = 0.002) and head (P = 0.012) displacements and increased muscle activity in comparison to non-scoliotic controls. Conclusion. Surgical alignment reduced the amount of sway, reduced the center of mass displacement, and reduced spine and lower extremity energy expenditure in ADS' patients. In symptomatic preoperative ADS patients, sagittal sway increased along with greater lumbar spine and lower extremity neuromuscular activity in comparison to a non-scoliotic control. Although surgical alignment improved ADS functional parameters during a dynamic balance test, these parameters approached but did not fully achieve non-scoliotic control parameters when measured 3 months after surgery. Level of Evidence: 3

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com

Medicine & Science in Sports & Exercise

Persistent Impairment in Cardiopulmonary Fitness after Breast Cancer Chemotherapy Purpose Anthracycline chemotherapy (AC) is associated with acute reductions in cardiopulmonary fitness (V˙O2peak). We sought to determine whether changes in V˙O2peak and cardiac function persisted at 12 months post-AC completion, and whether changes in cardiac function explain the heightened long-term heart failure risk. Methods Women with breast cancer scheduled for AC (n = 28) who participated in a nonrandomized trial of exercise training (ET; n = 14) or usual care (UC; n = 14) during AC completed a follow-up evaluation 12 months post-AC completion (16 months from baseline). At baseline, 4 months, and 16 months, participants underwent a resting echocardiogram (left ventricular ejection fraction; global longitudinal strain), a blood sample (troponin; B-type natriuretic peptide), a cardiopulmonary exercise test, and cardiac MRI measures of stroke volume (SV), heart rate, and cardiac output (Qc) at rest and during intense exercise. Results Seventeen women (UC, n = 8; ET, n = 9) completed evaluation at baseline, 4 months, and 16 months. At 4 months, AC was associated with 18% and 6% reductions in V˙O2peak in the UC and ET groups, respectively, which persisted at 16 months (UC, −16%; ET, −7%) and was not attenuated by ET (interaction, P = 0.10). Exercise Qc was lower at 16 months compared with baseline and 4 months (P < 0.001), which was due to a blunted augmentation of SV during exercise (P = 0.032; a 14% reduction in peak SV), with no changes in heart rate response. There was a small reduction in resting left ventricular ejection fraction (baseline to 4 months) and global longitudinal strain (between 4 and 16 months) and an increase in troponin (baseline to 4 months), but only exercise Qc was associated with V˙O2peak (R2 = 0.47, P < 0.01). Conclusion Marked reductions in V˙O2peak persisted 12 months after anthracycline-based chemotherapy, which was associated with impaired exercise cardiac function. Clinical Trial Registration: ACTRN12616001602415.

Effect of Creatine Supplementation on the Airways of Youth Elite Soccer Players Introduction Owing to its well-established ergogenic potential, creatine is a highly popular food supplement in sports. As an oral supplement, creatine is considered safe and ethical. However, no data exist on the safety of creatine on lung function in athletes. The aim of this project was to evaluate the effects of a standard course of creatine on the airways of youth elite athletes. Methods Nineteen elite soccer players, 16–21 yr old, completed a stratified, randomized, double-blind, placebo-controlled, parallel-group trial. The creatine group (n = 9) ingested 0.3 g·kg−1⋅d−1 of creatine monohydrate (CM) for 1 wk (loading phase) and 5 g·d−1 for 7 wk (maintenance phase), and the placebo group (n = 10) received the same dosages of maltodextrin. Airway inflammation (assessed by exhaled nitric oxide, FENO) and airway responsiveness (to dry air hyperpnoea) were measured pre- and postsupplementation. Results Mild, unfavorable changes in FENO were noticed by trend over the supplementation period in the CM group only (P = 0.056 for interaction, η2 = 0.199), with a mean group change of 9 ± 13 ppb in the CM group versus −5 ± 16 ppb in the placebo group (P = 0.056, d = 0.695). Further, the maximum fall in forced expiratory volume in 1 s after dry air hyperpnoea was larger by trend postsupplementation in the CM group compared with the placebo group: 9.7% ± 7.5% vs 4.4% ± 1.4%, respectively (P = 0.070, d = 0.975). These adverse effects were more pronounced when atopic players only (n = 15) were considered. Conclusion On the basis of the observed trends and medium to large effect sizes, we cannot exclude that creatine supplementation has an adverse effect on the airways of elite athletes, particularly in those with allergic sensitization. Further safety profiling of the ergogenic food supplement is warranted.

Testosterone and Resistance Training Improve Muscle Quality in Spinal Cord Injury Purpose Spinal cord injury (SCI) negatively impacts muscle quality and testosterone levels. Resistance training (RT) has been shown to increase muscle cross-sectional area (CSA) after SCI, whereas testosterone replacement therapy (TRT) has been shown to improve muscle quality in other populations. The purpose of this pilot study was to examine if the combined effects of these interventions, TRT + RT, may maximize the beneficial effects on muscle quality after SCI. Methods Twenty-two SCI subjects randomized into either a TRT + RT (n = 11) or TRT (n = 11) intervention for 16 wk. Muscle quality measured by peak torque (PT) at speeds of 0°·s−1 (PT-0°), 60°·s−1 (PT-60°), 90°·s−1 (PT-90°), and 180°·s−1 (PT-180°), knee extensor CSA, specific tension, and contractile speed (rise time [RTi], and half-time to relaxation [½TiR]) was assessed for each limb at baseline and postintervention using 2 × 2 mixed models. Results After 16 wk, subjects in the TRT + RT group increased PT-0° (48.4%, P = 0.017), knee extensor CSA (30.8%, P < 0.0001), and RTi (17.7%, P = 0.012); with no significant changes observed in the TRT group. Regardless of the intervention, changes to PT-60° (28.4%, P = 0.020), PT-90° (26.1%, P = 0.055), and PT-180° (20.6%, P = 0.09) for each group were similar. Conclusions The addition of mechanical stress via RT to TRT maximizes improvements to muscle quality after complete SCI when compared with TRT administered alone. Our evidence shows that this intervention increases muscle size and strength while also improving muscle contractile properties.

Bone Biomarker Response to Walking under Different Thermal Conditions in Older Adults Endurance exercise can cause a decrease in serum ionized calcium (iCa) and increases in parathyroid hormone (PTH) and c-terminal telopeptide of type I collagen (CTX), which may be due to Ca loss in sweat. Purpose This study aimed to determine whether exercise in a warm environment exaggerates the decrease in iCa and increases in PTH and CTX compared with a cool environment in older adults. Methods Twelve women and men 61–78 yr old performed two identical 60-min treadmill bouts at ~75% of maximal heart rate under warm and cool conditions. Serum iCa, PTH, and CTX were measured every 15 min starting 15 min before and continuing for 60 min after exercise. Sweat Ca loss was estimated from sweat volume and sweat Ca concentration. Results Sweat volume was low and variable; there were no differences in sweat volume or Ca concentration between conditions. iCa decreased after 15 min of exercise, and the change was similar in both conditions. Increases in PTH (warm: 16.4, 95% confidence interval [CI] = 6.2, 26.5 pg·mL−1; cool: 17.3, 95% CI = 8.1, 26.4 pg·mL−1) and CTX (warm: 0.08, 95% CI = 0.05, 0.11 ng·mL−1; cool: 0.08, 95% CI = 0.01, 0.16 ng·mL−1) from before to immediately after exercise were statistically significant and similar between conditions. Adjusting for plasma volume shifts did not change the results. Conclusion The increases in PTH and CTX, despite the low sweat volume, suggest that dermal Ca loss is not a major factor in the decrease in iCa and increases in PTH and CTX observed during exercise in older adults.

Objectively Measured Physical Activity Is Associated with Vertebral Size in Midlife Background Vertebral fractures reduce the quality of life and are a major burden to the health care sector. Small vertebral size is associated with increased vertebral fracture risk. Previous studies have investigated the relationship between physical activity (PA) and vertebral size, but their results seem somewhat contradictory. In this population-based birth cohort study, we aimed to evaluate the relationship between objectively measured PA and vertebral size. Methods The study population consisted of 1202 cohort participants who underwent PA and vertebral size measurements at the age of 46 to 48 yr. Moderate-to-vigorous PA (MVPA, ≥3.5 METs) was measured by a wrist-worn accelerometer (Polar Active; Polar Electro, Finland) for 14 d. The vertebral axial cross-sectional area (CSA) of the L4 vertebra was measured and calculated from lumbar magnetic resonance imaging scans at 46 to 48 yr. We analyzed the association between the daily amount of MVPA (min·d−1) and vertebral CSA using multivariable linear regression analysis. Results The daily amount of MVPA was significantly and positively associated with CSA in both sexes. For every minute per day of MVPA, men had 0.71 mm2 (95% confidence interval, 0.36–1.06) and women 0.90 mm2 (95% confidence interval, 0.58–1.21) larger CSA. Conclusions Physical activity of at least moderate intensity is positively associated with vertebral size and may thus prevent future vertebral fractures.

Sedentary Time and White Matter Hyperintensity Volume in Older Adults Purpose Cerebrovascular disease in the form of white matter hyperintensities (WMH) increases with age and is associated separately with sedentary time and reduced kidney function. A better understanding of the relationships among these variables would help clarify whether sedentary time should be considered more closely in older adults at particular levels of kidney function to reduce the risk of WMH. Methods We analyzed information from 94 healthy community-dwelling older adults to determine the association of sedentary time and WMH in nondemented, nondepressed older adults, and whether level of kidney function was an effect modifier of the relationship between sedentary time and WMH. Sedentary behavior was measured using the Sedentary Behavior Questionnaire. White matter hyperintensity was assessed using whole-brain 3T magnetic resonance imaging T1- and T2-weighted images. Kidney function was calculated by the epi-chronic kidney disease formula for estimated glomerular filtration rate (eGFR). Exposures or predictors were sedentary time, age, sex, education in years, Framingham stroke risk 10-yr prediction score, and eGFR. The analytical approach was multiple linear regression. Results Adjusting for age, sex, education in years, Framingham stroke risk 10-yr prediction score, greater sedentary time was associated with greater WMH but this effect was dependent on level of eGFR (sedentary time–eGFR interaction b = −0.0005, P = 0.022). At eGFR values of 69, 81, and 93 mL·min−1 per 1.73 m2 (the 25th, 50th, and 75th percentiles), sedentary time b coefficients were b = 0.021 (95% confidence interval [CI], 0.011–0.031), b = 0.015 (95% CI, 0.008–0.022), and b = 0.009 (95% CI, 0.003–0.016). The effect weakened linearly as eGFR increased, with no significant association at eGFR ≥97 mL·min−1 per 1.73 m2. Conclusions Findings suggest that sedentary time is associated with WMH in persons with an eGFR ≤96 mL·min−1 per 1.73 m2 and that this association is stronger with lower levels of kidney function.

Shared Neuromuscular Performance Traits in Military Personnel with Prior Concussion Concussions are common in military personnel and may result in increased risk of musculoskeletal injury. One plausible explanation for this risk could be that neuromotor deficiencies enhance injury risk after a concussion through altered muscular activation/contraction timing. Purpose To compare military personnel with at least one concussion during the past 1 month to 2 yr (CONCUSSED) to military branch-matched, age-matched, and Special Operations Forces group–matched controls (CONTROL) on physiological, musculoskeletal, and biomechanical performance. Methods A total of 48 (24 CONCUSSED, 24 CONTROL) male Air Force and Naval Special Warfare Operators age 19 to 34 yr participated in the study. Participants self-reported demographics/injury history and completed the following assessments: 1) physiological—body composition, anaerobic power and capacity, aerobic capacity and lactate threshold; 2) musculoskeletal—lower extremity isokinetic strength testing, including time to peak torque; and 3) biomechanical—single-leg jump and landing task, including landing kinematics of the hip, knee and ankle. A machine learning decision tree algorithm (C5.0) and one-way ANOVA were used to compare the two groups on these outcomes. Results Despite nonsignificant differences using ANOVA, the C5.0 algorithm revealed CONCUSSED demonstrated quicker time to peak knee flexion angle during the single-leg landing task (≤0.170 s; CONCUSSED: n = 22 vs CONTROL: n = 14), longer time to peak torque in knee extension isokinetic strength testing (>500 ms; CONCUSSED: n = 18 vs CONTROL: n = 4) and larger knee flexion angle at initial contact (>7.7°; CONCUSSED: n = 18 vs CONTROL: n = 2). Conclusion The findings supported the hypothesis that CONCUSSED military personnel would demonstrate altered neuromuscular control in landing strategies and muscular activation. Future research should assess prospectively neuromuscular changes after a concussion and determine if these changes increase risk of subsequent musculoskeletal injuries.

Loading Behaviors Do Not Match Loading Abilities Postanterior Cruciate Ligament Reconstruction Purpose Strategies that underload the surgical limb after anterior cruciate ligament reconstruction (ACLr) are observed in submaximal tasks. It is not known what underlies these strategies in early rehabilitation. The purpose of this study was to determine if underloading can be attributed to the inability to meet task demands with and without attention to limb loading or learned behavior. Methods Twenty individuals (110.6 [18.1] days) post-ACLr and 20 healthy individuals (CTRL) participated in this study. Participants performed standing, sit-to-stand, and squat tasks under natural, instructed, and feedback conditions. Limb-loading symmetry was calculated as the between-limb ratio of vertical ground reaction force impulse during each task. General Linear Model repeated-measures analysis, 2 (group) × 3 (condition), determined the effects of group and condition on limb-loading symmetry for each task. Results Significant interactions were observed for each task (all P < 0.001). Compared with CTRL, ACLr exhibited greater asymmetry during natural (deficits: standing, 10%, P = 0.001; sit-to-stand, 25%, P < 0.001; squat, 15%, P < 0.001) and instructed (deficits: sit-to-stand, 13%, P = 0.001; squat, 8%, P = 0.04), but not feedback conditions. The CTRL maintained symmetry across conditions and tasks. Anterior cruciate ligament reconstruction exhibited greater asymmetry in natural compared with instructed (deficits: standing, 11%, P < 0.001; sit-to-stand, 14%, P < 0.001; squat, 8%, P = 0.001) and feedback (deficits: standing, 10%, P = 0.001; sit-to-stand, 21%, P < 0.001; squat, 15%, P < 0.001) conditions. Conclusions The presence of loading asymmetries in natural but not feedback conditions indicates that individuals 3 months post-ACLr shift loading away from surgical limb despite the ability to meet task demands which may be suggestive of nonuse behavior. Even when instructed to load symmetrically, individuals continued to exhibit some degree of asymmetry.

Effects of Exercise on Stress-induced Attenuation of Vaccination Responses in Mice Studies suggest that exercise can improve vaccination responses in humans. Chronic stress can lead to immunosuppression, and there may be a role for exercise in augmenting immune responses. Purpose To investigate the effects of acute eccentric exercise (ECC) and voluntary wheel exercise training (VWR) on antibody and cell-mediated immune responses to vaccination in chronically stressed mice. We hypothesized that both ECC and VWR would attenuate chronic stress-induced reductions in vaccination responses. Methods Mice were randomized into four groups: control (CON), stress (S)-ECC, S-VWR, and S-sedentary (SED). Stressed groups received chronic restraint stress for 6 h·d−1, 5 d·wk−1 for 3 wk. After the first week of stress, S-ECC were exercised at 17 m·min−1 speed at −20% grade for 45 min on a treadmill and then intramuscularly injected with 100 μg of ovalbumin (OVA) and 200 μg of alum adjuvant. All other groups were also vaccinated at this time. Stress-VWR mice voluntarily ran on a wheel for the entire experiment. Plasma was collected before, and at 1, 2, and 4 wk postvaccination. Enzyme-linked immunosorbent assay was performed to analyze anti-OVA IgG and IgM antibodies. After 3 wk of chronic stress, all mice were injected with OVA into the ear to determine the delayed-type hypersensitivity. Results We found that chronic restraint stress significantly reduced body weight and caused adrenal hypertrophy. We also found both S-ECC and S-VWR groups had significantly elevated anti-OVA IgG (P < 0.05), whereas no significant differences between the two exercise groups. Neither S-ECC nor S-VWR altered anti-OVA IgM or delayed-type hypersensitivity responses compared with S-SED group. Conclusions Acute eccentric exercise and voluntary exercise training alleviated the chronic stress-induced anti-OVA IgG reductions in vaccination responses.

Neuromuscular Fatigue and Metabolism during High-Intensity Intermittent Exercise Purpose To examine the degree of neuromuscular fatigue development along with changes in muscle metabolism during two work-matched high-intensity intermittent exercise protocols in trained individuals. Methods In a randomized, counter-balanced, crossover design, 11 endurance-trained men performed high-intensity intermittent cycle exercise protocols matched for total work and including either multiple short-duration (18 × 5 s; SS) or long-duration (6 × 20 s; LS) sprints. Neuromuscular fatigue was determined by preexercise to postexercise changes in maximal voluntary contraction force, voluntary activation level and contractile properties of the quadriceps muscle. Metabolites and pH were measured in vastus lateralis muscle biopsies taken before and after the first and last sprint of each exercise protocol. Results Peak power output (11% ± 2% vs 16% ± 8%, P < 0.01), maximal voluntary contraction (10% ± 5% vs 25% ± 6%, P < 0.05), and peak twitch force (34% ± 5% vs 67% ± 5%, P < 0.01) declined to a lesser extent in SS than LS, whereas voluntary activation level decreased similarly in SS and LS (10% ± 2% vs 11% ± 4%). Muscle [phosphocreatine] before the last sprint was 1.5-fold lower in SS than LS (P < 0.001). Preexercise to postexercise intramuscular accumulation of lactate and H+ was twofold and threefold lower, respectively, in SS than LS (P < 0.001), whereas muscle glycogen depletion was similar in SS and LS. Rate of muscle glycolysis was similar in SS and LS during the first sprint, but twofold higher in SS than LS during the last sprint (P < 0.05). Conclusions These findings indicate that, in endurance-trained individuals, multiple long-sprints induce larger impairments in performance along with greater degrees of peripheral fatigue compared to work-matched multiple short-sprints, with these differences being possibly attributed to more extensive intramuscular accumulation of lactate/H+ and to lower rates of glycolysis during multiple long-sprint exercise.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com