Implementation of genomic medicine for rare disease in a tertiary healthcare system: Mayo Clinic Program for Rare and Undiagnosed Diseases (PRaUD)

BACKGROUND

In the United States, rare disease (RD) is defined as a condition that affects fewer than 200,000 individuals. Collectively, RD affects an estimated 30 million Americans. A significant portion of RD has an underlying genetic cause; however, this may go undiagnosed. To better serve these patients, the Mayo Clinic Program for Rare and Undiagnosed Diseases (PRaUD) was created under the auspices of the Center for Individualized Medicine (CIM) aiming to integrate genomics into subspecialty practice including targeted genetic testing, research, and education.

METHODS

Patients were identified by subspecialty healthcare providers from 11 clinical divisions/departments. Targeted multi-gene panels or custom exome/genome-based panels were utilized. To support the goals of PRaUD, a new clinical service model, the Genetic Testing and Counseling (GTAC) unit, was established to improve access and increase efficiency for genetic test facilitation. The GTAC unit includes genetic counselors, genetic counseling assistants, genetic nurses, and a medical geneticist. Patients receive abbreviated point-of-care genetic counseling and testing through a partnership with subspecialty providers.

RESULTS

Implementation of PRaUD began in 2018 and GTAC unit launched in 2020 to support program expansion. Currently, 29 RD clinical indications are included in 11 specialty divisions/departments with over 142 referring providers. To date, 1152 patients have been evaluated with an overall solved or likely solved rate of 17.5% and as high as 66.7% depending on the phenotype. Noteworthy, 42.7% of the solved or likely solved patients underwent changes in medical management and outcome based on genetic test results.

CONCLUSION

Implementation of PRaUD and GTAC have enabled subspecialty practices advance expertise in RD where genetic counselors have not historically been embedded in practice. Democratizing access to genetic testing and counseling can broaden the reach of patients with RD and increase the diagnostic yield of such indications leading to better medical management as well as expanding research opportunities.

Spasticity Interventions: Decision-Making and Management

Spasticity results from an abnormality of the central nervous system and is characterized by a velocity-dependent increase in muscle tone or stiffness. In children, it can cause functional impairments, delays in achieving developmental or motor milestones, participation restrictions, discomfort, and musculoskeletal differences. Unique to children is the ongoing process of a maturing central nervous system and body, which can create the appearance of worsening or changing spasticity. Treatment options include physical interventions such as stretching, serial casting, and bracing; oral and injectable medications; and neurosurgical procedures such as selective dorsal rhizotomy and intrathecal baclofen pump.

Current status and trends in subspecialty certification in physical medicine and rehabilitation

BACKGROUND

There is a need to better understand the overall state of sub-specialization in physical medicine and rehabilitation (PM&R).

OBJECTIVE

To examine the status and trends in subspecialty certification for each of the seven subspecialties approved for American Board of Physical Medicine and Rehabilitation (ABPMR) diplomates.

DESIGN/SETTING

Retrospective analysis of deidentified information from the ABPMR database.

PARTICIPANTS

Physicians certified by ABPMR through 2019.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

For each subspecialty, we examined: (1) the number of certificates issued to ABPMR diplomates; (2) the recertification rate; (3) the yearly trends for total active, new, and expired certificates; and (4) for ABPMR-administered subspecialties, recertification rates for those entering the subspecialty through fellowship completion versus a "grandfathered" practice pathway.

RESULTS

Of 11,421 ABPMR diplomates in the United States in 2019, a total of 3560 (31.2%) had 3985 active subspecialty certificates. Pain Medicine (PM) was the most common subspecialty certification (15.5% of all ABPMR diplomates) followed by Sports Medicine (SM, 6.6%), Brain Injury Medicine (BIM, 4.8%), Spinal Cord Injury Medicine (SCIM, 4.2%), Pediatric Rehabilitation Medicine (PRM, 2.5%), Neuromuscular Medicine (NMM, 0.7%), and Hospice and Palliative Medicine (HPM, 0.5%). For diplomates with more than one subspecialty certification, PM and SM was the most frequent combination. Both the recertification rate and the end of practice track eligibility influenced certification trends differently for individual subspecialties. The average number of new certificates added annually for every subspecialty was higher before than after the temporary practice track-based eligibility ended; the difference was statistically significant (p < .05) for SCIM, PM, SM, and NMM. The recertification rate for all subspecialties combined was 73.4%. For the subspecialties (SCIM, PRM) for which these data were available, fellowship candidates had higher recertification rates than those grandfathered through a practice track.

CONCLUSION

This report informs stakeholders about the state and evolution of subspecialty certification in PM&R over time.

Physician distress: Where are we and what can be done

Depression, suicidal ideation, burnout, and moral injury are on the rise among physicians. Depression and suicidal ideation are mental health disorders that result from multiple interacting factors including biological vulnerabilities and acute stressors. Medical treatment for depression and suicidal ideation is critical to interrupt the potentially deadly progression to suicide that occurs when one's ability to find hope and other solutions is clouded by despair. Yet, stigma and perceived stigma of seeking treatment for mental health disorders still plagues medical providers. Transitions during medical training and practice can be particularly vulnerable time periods, though newer evidence suggests that overall, physicians are not at an increased risk of suicide compared to the general population. While burnout and moral injury are common among rehabilitation physicians, unlike depression, they are not directly associated with suicidal ideation. Opportunities for continued improvement in mental health resources and institutional support exist across the spectrum from medical student to staff physician. With wellness now increasingly supported and promoted by various medical organizations and recognition of the importance of access to effective mental health treatment, regaining hope and positivity while restoring resiliency in physicians, trainees, and medical students is possible.

Why Do Physical Medicine and Rehabilitation Physicians Lose American Board of Physical Medicine and Rehabilitation Board Certification?

OBJECTIVE

Physicians can lose board certification through revocation related to professionalism violations or expiration due to failure to complete continuing certification requirements. The purpose of this study was to analyze the causes of board certification loss for physicians with board certification through the American Board of Physical Medicine and Rehabilitation.

DESIGN

This retrospective cohort study analyzed the certification status of 5541 American Board of Physical Medicine and Rehabilitation diplomates between 1993 and 2019 to determine reasons for certification loss. A focused analysis of diplomates with expired certificates in 2019 was conducted to further examine reasons for certificate expiration.

RESULTS

Of 5541 physicians, 496 (9%) had certification expiration due to failure to meet continuing certification requirements and 60 (1%) had certification revocation due to disciplinary actions, without regaining certification across the study years. A focused analysis of physicians with expired certificates in 2019 revealed that the majority had failed to complete multiple components of continuing certification. Practice improvement was the single most common incomplete requirement. Failure to pass the knowledge assessment was an uncommon cause for certification loss.

CONCLUSIONS

Certification expiration through failure to complete all continuing certification requirements, versus revocation, is responsible for most instances of board certification loss. Practice improvement was the most common incomplete requirement.

American Board of Physical Medicine and Rehabilitation Diplomate Customization Choices on the Longitudinal Assessment for Physical Medicine and Rehabilitation: A First-Year Experience

ABSTRACT

The American Board of Physical Medicine and Rehabilitation began administering the longitudinal assessment for physical medicine and rehabilitation for continuing certification in 2020. The longitudinal assessment for physical medicine and rehabilitation digitally delivers quarterly short assessments of content and repeats missed items to facilitate learning as well as serve as a summative certification assessment. With a goal of offering content relevant to an individual's practice and learning needs, diplomates choose how to customize the domains or topic areas of their question content on an annual basis. This report describes the first year of experience with customization of longitudinal assessment for physical medicine and rehabilitation. The American Board of Physical Medicine and Rehabilitation diplomate customization data are grouped and compared in a variety of ways to ascertain whether there are differences in customization choices. While customization choices were similar across several domains, significant differences were seen when comparing groups with specific areas of practice or subspecialty certification. Smaller differences were also seen when comparing question domain allocation choice between sexes, age groups, and practice setting. The results from this first full year of experience confirm an alignment of this innovative assessment approach to individual physician practice, a significant step in improving the relevance of continuing certification overall for participating physicians.

Taking Leave During Residency: Types of Absences and Subsequent Delays and Variations in Physical Medicine and Rehabilitation Medical Board Pass Rates

ABSTRACT

There is limited literature examining the reasons physical medicine and rehabilitation residents take an extended leave of absence during residency and the impact of leave on board examination performance. Such information could better inform leave policies, help guide residency program directors, and potentially destigmatize taking leave. Study objectives were to describe the characteristics of physical medicine and rehabilitation residents who take leave during residency, compare differences in part I (written) and part II (oral) certification examination performance, and determine the prevalence of delays in taking board examinations. Study methodology was a retrospective analysis of deidentified information from the American Board of Physical Medicine and Rehabilitation database between 2008 and 2020. Results indicated four reasons for extended leave of absence: medical, parental, academic/remediation, and unspecified personal reasons. Residents who took an extended leave of absence for medical or parental reasons had similar or better odds of passing their part I and part II examinations compared with those without leave. Residents who took leave for academic/remediation concerns or unspecified personal reasons had lower odds of passing their board examinations. Examination delays for those taking parental or personal health leaves did not affect board pass rates. Further investigation is needed to identify how to support residents on academic/remediation and unspecified leaves during training.

Key Findings From Peer-Reviewed Published Research by the American Board of Physical Medicine and Rehabilitation in Review

ABSTRACT

Recognizing the dearth of published research on board certification in physical medicine and rehabilitation and its subspecialties, the American Board of Physical Medicine and Rehabilitation has increased efforts to conduct and disseminate research in this area. This report summarizes key findings of peer-reviewed studies published by American Board of Physical Medicine and Rehabilitation staff and leadership in the past 6 yrs, including those conducted in partnership with other entities. The reported studies are organized in three main categories: initial certification, continuing certification, and subspecialty certification in physical medicine and rehabilitation. Related findings are further grouped into subsections that include psychometric evaluation of certification examinations, association of candidate characteristics with certification performance, relationship of certification performance to other measures, and candidate reaction and feedback. Collectively, the summarized results provide evidence that the board certification process is reliable, statistically valid, and predictive of the risk of disciplinary action in subsequent years. These studies also describe facets of our specialty including degree of subspecialization, burnout, and how people maintain certification over time. We hope that physical medicine and rehabilitation trainees, diplomates, institutions, programs, and other stakeholders find this information useful and look forward to continuing research in these and other areas in the spirit of constant evidence-based improvement and feedback to our specialty.

Safety and efficacy of (+)-epicatechin in subjects with Friedreich's ataxia: A phase II, open-label, prospective study

BACKGROUND

(+)-Epicatechin (EPI) induces mitochondrial biogenesis and antioxidant metabolism in muscle fibers and neurons. We aimed to evaluate safety and efficacy of (+)-EPI in pediatric subjects with Friedreich's ataxia (FRDA).

METHODS

This was a phase II, open-label, baseline-controlled single-center trial including 10 participants ages 10 to 22 with confirmed FA diagnosis. (+)-EPI was administered orally at 75 mg/d for 24 weeks, with escalation to 150 mg/d at 12 weeks for subjects not showing improvement of neuromuscular, neurological or cardiac endpoints. Neurological endpoints were change from baseline in Friedreich's Ataxia Rating Scale (FARS) and 8-m timed walk. Cardiac endpoints were changes from baseline in left ventricular (LV) structure and function by cardiac magnetic resonance imaging (MRI) and echocardiogram, changes in cardiac electrophysiology, and changes in biomarkers for heart failure and hypertrophy.

RESULTS

Mean FARS/modified (m)FARS scores showed nonstatistically significant improvement by both group and individual analysis. FARS/mFARS scores improved in 5/9 subjects (56%), 8-m walk in 3/9 (33%), 9-peg hole test in 6/10 (60%). LV mass index by cardiac MRI was significantly reduced at 12 weeks (P = .045), and was improved in 7/10 (70%) subjects at 24 weeks. Mean LV ejection fraction was increased at 24 weeks (P = .008) compared to baseline. Mean maximal septal thickness by echocardiography was increased at 24 weeks (P = .031). There were no serious adverse events.

CONCLUSION

(+)-EPI was well tolerated over 24 weeks at up to 150 mg/d. Improvement was observed in cardiac structure and function in subset of subjects with FRDA without statistically significant improvement in primary neurological outcomes.

SYNOPSIS

A (+)-epicatechin showed improvement of cardiac function, nonsignificant reduction of FARS/mFARS scores, and sustained significant upregulation of muscle-regeneration biomarker follistatin.

The Telemedicine Musculoskeletal Examination

Telemedicine uses modern telecommunication technology to exchange medical information and provide clinical care to individuals at a distance. Initially intended to improve health care for patients in remote settings, telemedicine now has a broad clinical scope with the general purpose of providing convenient, safe, and time- and cost-efficient care. The coronavirus disease 2019 pandemic has created marked nationwide changes in health care access and delivery. Elective appointments and procedures have been canceled or delayed, and multiple states still have some degree of shelter-in-place orders. Many institutions are now relying more heavily on telehealth services to continue to provide medical care to individuals while also preserving the safety of health care professionals and patients. Telemedicine can also help reduce the surge in health care needs and visits as restrictions are lifted. In recent weeks, there has been a significant amount of information and advice on how to best approach telemedicine visits. Given the frequent presentation of individuals with musculoskeletal complaints to the medical practitioner, it is important to have a framework for the virtual musculoskeletal physical examination. This will be of importance as telemedicine continues to evolve, even after coronavirus disease 2019 restrictions are lifted. This article will provide the medical practitioner performing a virtual musculoskeletal examination with a specific set of guidelines, both written and visual, to enhance the information obtained when evaluating the shoulder, hip, knee, ankle, and cervical and lumbar spine. In addition to photographs, accompanying videos are included to facilitate and demonstrate specific physical examination techniques that the patient can self-perform.

Pediatric telerehabilitation medicine: Making your virtual visits efficient, effective and fun

The COVID-19 pandemic has accelerated many changes in medicine including the transition from providing care in person to providing care via technology enabled telemedicine. The benefits of telemedicine visits with a Pediatric Rehabilitation Medicine (PRM) provider, also known as telerehabilitation medicine visits, are numerous. Telerehabilitation medicine provides an opportunity to deliver timely, patient and family-centric rehabilitation care while maintaining physical distance and reducing potential COVID-19 exposure for our patients, their caregivers and medical providers. Telerehabilitation medicine also allows for access to PRM care in rural areas or areas without medical specialty, virtual in-home equipment evaluation, and reduced travel burden. Because of these and many other benefits, telerehabilitation medicine will likely become part of our ongoing model of care if barriers to telemedicine continue to be lowered or removed. This paper is intended to establish a foundation for pediatric telerehabilitation medicine visit efficiency and effectiveness in our current environment and into the future.

Posterior Vertebral Endplate Fractures: A Retrospective Study on a Rare Etiology of Back Pain in Youth and Young Adults

BACKGROUND

Posterior lumbar vertebral endplate fracture occurs with avulsion of the ring apophysis from the posterior vertebral body. Although this has been described in adolescents and young adults, proper diagnosis is often delayed or missed entirely. Surgery may be curative.

OBJECTIVE

To determine the common clinical features and treatment outcomes in youth and young adults with posterior lumbar vertebral endplate fractures.

DESIGN

Retrospective case series.

SETTING

Academic medical institution.

PATIENTS

Patients 10 to 25 years old from 2000 through 2012 with posterior vertebral endplate fracture diagnosis.

MAIN OUTCOME MEASUREMENTS

Demographic characteristics, diagnostic studies, interventions, and change in symptoms postoperatively.

RESULTS

A total of 16 patients had posterior vertebral endplate fractures (8 male patients; mean age, 15.2 years)-8.3% of 192 patients with inclusion age range undergoing spinal surgery for causes unrelated to trauma, scoliosis, or malignancy. The most common signs and symptoms were low back and radiating leg pain, positive straight leg raise, hamstring contracture, and abnormal gait. Cause was sports related for 12 patients (75%). Mean (range) time to diagnosis was 13.0 (3.0-63.0) months. Diagnosis was most commonly made with lumbar magnetic resonance imaging (n = 6). Most fractures occurred at L5 (n = 8, 50%) and L4 (n = 5, 31.3%). Conservative measures were trialed before surgery. Nine patients had "complete relief" following surgery and seven "improved."

CONCLUSIONS

Posterior vertebral endplate fracture should be considered in differential diagnosis of a youth or young adult with back pain, radiating leg pain, and limited knee extension, regardless of symptom onset. For patients in whom conservative management fails, consultation with an experienced physician whose practice specializes in spine medicine is recommended.

LEVEL OF EVIDENCE

IV.

Should There Be A Part II ABPMR Examination?: A Psychometric Inquiry

BACKGROUND

Certification by the American Board of Physical Medicine and Rehabilitation (ABPMR) requires passing both a written multiple choice examination (Part I) and an oral examination (Part II), but it has been unclear whether the two examinations measure the same or different dimensions of knowledge.

OBJECTIVE

To evaluate the concordance between the Part I and Part II examinations for ABPMR initial certification with regard to candidate performance on the examinations and their subsets. Our question is whether the Part II examination provides additional assessment of a candidate beyond what Part I provides.

DESIGN

Retrospective psychometric evaluation of deidentified board examination scores.

SETTING

ABPMR database of Part I and Part II examination scores.

PARTICIPANTS

Candidates for the ABPMR Part I and Part II examinations after 2005, with a more detailed analysis of candidates for the Part I examination from 2014 to 2016. Examination scores of candidates who took the Part II examination both before and after the examination was standardized in 2005 were also used for an additional analysis.

METHODS

Correlations, simple linear regressions, and principal components analysis.

MAIN OUTCOME MEASUREMENTS

Correlation coefficients, variance analysis, and unexplained variance in the principal components analysis.

RESULTS

There is a weak to moderate correlation between performance on the Part I and Part II examinations: r = 0.33, P < .001. There is an additional dimension of assessment that is demonstrated on the Part II examination, with this being primarily in the domains of systems-based practice and interpersonal communication skills.

CONCLUSION

The Part I and Part II examinations, although with some overlap, contribute different and meaningful components to the overall evaluation of candidates for board certification in PM&R.

LEVEL OF EVIDENCE

III.

Interdisciplinary aerodigestive care model improves risk, cost, and efficiency

OBJECTIVE

This study sought to evaluate the impact of an interdisciplinary care model for pediatric aerodigestive patients in terms of efficiency, risk exposure, and cost.

METHODS

Patients meeting a standard clinical inclusion definition were studied before and after implementation of the aerodigestive program.

RESULTS

Aerodigestive patients seen in the interdisciplinary clinic structure achieved a reduction in time to diagnosis (6 vs 150 days) with fewer required specialist consultations (5 vs 11) as compared to those seen in the same institution prior. Post-implementation patients also experienced a significant reduction in risk, with fewer radiation exposures (2 vs 4) and fewer anesthetic episodes (1 vs 2). Total cost associated with the diagnostic evaluation was significantly reduced from a median of $10,374 to $6055.

CONCLUSION

This is the first study to utilize a pre-post cohort to evaluate the reduction in diagnostic time, risk exposure, and cost attributable to the reorganization of existing resources into an interdisciplinary care model. This suggests that such a model yields improvements in care quality and value for aerodigestive patients, and likely for other pediatric patients with chronic complex conditions.

Predictors of Performance on the American Board of Physical Medicine and Rehabilitation Maintenance of Certification Examination

BACKGROUND

Maintenance of certification (MOC) in Physical Medicine and Rehabilitation is a process of lifelong learning that begins after successfully completing an Accreditation Council for Graduate Medical Education (ACGME)-accredited residency and passing the American Board of Physical Medicine and Rehabilitation (ABPMR) Part I and Part II Examinations. We seek to identify factors predictive of successful MOC Examination performance.

OBJECTIVE

To identify characteristics predictive of successful completion on the ABPMR MOC Examination.

DESIGN

Retrospective review.

SETTING

American Board of Physical Medicine and Rehabilitation database review.

PARTICIPANTS

4,545 diplomates who completed the MOC Examination between January 2006 and December 2017.

METHODS

MOC Examination performance was the primary outcome variable. Performance on Part I and Part II Examinations were independent variables. Additional potential predictors evaluated included year of MOC cycle in which examination was taken, years of practice since residency completion, age, and subspecialty certification.

MAIN OUTCOME MEASURES

Performance on MOC Examination.

RESULTS

Age at time of MOC Examination was inversely correlated with examination score (r = -0.14, P < .001). Similarly, as time since completion of residency training increased, MOC scores declined. Passing the Part I Examination on first attempt predicted a 98% MOC pass rate, compared to 90% for those who failed initially. MOC performance was highly correlated with Part I performance (r = 0.59, P < .001) and Part II performance (r = 0.32, P < .001). Although MOC performance was similar for those taking the examination in years 7 - 10 of their cycle (97% pass rate), those taking the examination after more than 10 years of the cycle had a significantly lower performance (85% pass rate, P < .01).

CONCLUSIONS

Better performance on the MOC Examination is associated with better performance on Part I and Part II Examinations, taking the examination earlier in the 10 year cycle, younger age, and less time since completion of training. Diplomates who are at higher risk for failing the examination may need to prepare differently for MOC Exam than those who are more likely to pass.

LEVEL OF EVIDENCE

III.

Performance of Pediatric Rehabilitation Medicine Candidates on the Subspecialty Board Certification Examination from 2003 to 2015

BACKGROUND

Pediatric rehabilitation medicine (PRM) physicians enter the field via several pathways. It is unknown whether different training pathways impact performance on the American Board of Physical Medicine and Rehabilitation (ABPMR) PRM Examination and Maintenance of Certification (MOC) Examination.

OBJECTIVES

To describe the examination performance of candidates on the ABPMR PRM Examination according to their type of training (physiatrists with a clinical PRM focus, accredited or unaccredited fellowship training, separate pediatric and physical medicine and rehabilitation residencies, or combined pediatrics/physical medicine and rehabilitation residencies) and to compare candidates' performance on the PRM Examination with their initial ABPMR certification and MOC Examinations.

DESIGN

A retrospective cohort study.

SETTING

American Board of Physical Medicine and Rehabilitation office.

PARTICIPANTS

A total of 250 candidates taking the PRM subspecialty certification examination from 2003 to 2015.

METHODS

Scaled scores on the PRM Examination were compared to the examinees' initial certification scores as well as their admissibility criteria. Pass rates and scaled scores also were compared for those taking their initial PRM certification versus MOC.

MAIN OUTCOME MEASUREMENTS

Board pass rates and mean scaled scores for initial PRM Examination and MOC.

RESULTS

The 250 physiatrists who took the subspecialty PRM Examination had an overall first-time pass rate of 89%. There was no significant difference between first-time PRM pass rates or mean scaled scores for individuals who completed an Accreditation Council for Graduate Medical Education-accredited fellowship versus those who did not. First time PRM pass rates were greatest among those who were also certified by the American Board of Pediatrics (100%). Performance on Parts I and II of the initial ABPMR Certification Examination significantly predicted PRM Examination scores. There was no difference in mean scaled scores for initial PRM certification versus taking the PRM Examination for MOC.

CONCLUSIONS

Several pathways to admissibility to the PRM Examination afforded similar opportunity for diplomates to gain the knowledge necessary to pass the PRM Examination. Once certified, physicians taking the PRM Examination for MOC have a high success rate of passing again in years 7-10 of their certification cycle.

LEVEL OF EVIDENCE

III.

Adolescent fatigue, POTS, and recovery: a guide for clinicians

Many teenagers who struggle with chronic fatigue have symptoms suggestive of autonomic dysfunction that may include lightheadedness, headaches, palpitations, nausea, and abdominal pain. Inadequate sleep habits and psychological conditions can contribute to fatigue, as can concurrent medical conditions. One type of autonomic dysfunction, postural orthostatic tachycardia syndrome, is increasingly being identified in adolescents with its constellation of fatigue, orthostatic intolerance, and excessive postural tachycardia (more than 40 beats/min). A family-based approach to care with support from a multidisciplinary team can diagnose, treat, educate, and encourage patients. Full recovery is possible with multi-faceted treatment. The daily treatment plan should consist of increased fluid and salt intake, aerobic exercise, and regular sleep and meal schedules; some medications can be helpful. Psychological support is critical and often includes biobehavioral strategies and cognitive-behavioral therapy to help with symptom management. More intensive recovery plans can be implemented when necessary.

Orthostatic heart rate and blood pressure in adolescents: reference ranges

This descriptive population study of 307 public high school students, ages 15 to 17 years, was performed to establish reference ranges for orthostatic changes in heart rate and blood pressure in adolescents, and to identify influential variables. Noninvasive measurements of blood pressure and heart rate were obtained. Reference ranges for orthostatic heart rate change in this population at 2 minutes were -2 to +41 beats per minute and at 5 minutes were -1 to +48 beats per minute. Orthostatic blood pressure changes were within the adult range for 98% of adolescents tested. One-third of participants experienced orthostatic symptoms during testing. In conclusion, this study shows that orthostatic symptoms and large orthostatic heart rate changes occur in adolescents. This suggests that the current orthostatic heart rate criterion aiding the diagnosis of adult orthostatic intolerance syndromes is likely not appropriate for adolescents and should be reevaluated.

Musculoskeletal complications of neuromuscular disease in children

A wide variety of neuromuscular diseases affect children, including central nervous system disorders such as cerebral palsy and spinal cord injury; motor neuron disorders such as spinal muscular atrophy; peripheral nerve disorders such as Charcot-Marie-Tooth disease; neuromuscular junction disorders such as congenital myasthenia gravis; and muscle fiber disorders such as Duchenne's muscular dystrophy. Although the origins and clinical syndromes vary significantly, outcomes related to musculoskeletal complications are often shared. The most frequently encountered musculoskeletal complications of neuromuscular disorders in children are scoliosis, bony rotational deformities, and hip dysplasia. Management is often challenging to those who work with children who have neuromuscular disorders.

Cellular origin and evolution of neochondrogenesis in major full-thickness defects of a joint surface treated by free autogenous periosteal grafts and subjected to continuous passive motion in rabbits

A graft of periosteum from the tibia of 27 rabbits was incubated in vitro with tritiated thymidine for 24 hours and then transplanted into a full-thickness defect in the patellar groove. The rabbits were managed after the operation on continuous passive motion (CPM), and the joints excised at intervals of two to 21 days. After one week the cells had begun to synthesize glycosaminoglycan and by two weeks the tissue resembled immature hyaline cartilage. Thymidine-labeled cells were seen throughout the entire regenerated tissue. The cellular origin of the hyaline-like tissue that filled the defects was the progenitor cells of the periosteal graft.