Respiratory events and obstructive sleep apnea in children with achondroplasia: investigation and treatment outcomes

Clinical outcomes and medical management of achondroplasia in Japanese children: A retrospective medical record review of clinical data

Achondroplasia (ACH) is a rare, autosomal dominant skeletal dysplasia characterized by short stature, characteristic facial configuration, and trident hands. Before vosoritide approval in Japan, patients with ACH could start growth hormone (GH) treatment at age 3 years. However, ACH and its treatment in young Japanese children have not been studied. This retrospective, longitudinal, medical records-based cohort study (before vosoritide approval) summarized symptoms, complications, monitoring, surgery/interventions, and height with/without GH in Japanese patients with ACH <5 years. Complications were observed in 89.2% of all 37 patients; 75.7% required surgery or intervention. All patients were monitored by magnetic resonance imaging; 73.0% had foramen magnum stenosis, while 54.1% had Achondroplasia Foramen Magnum Score 3 or 4. Of 28 GH-treated patients, 22 initiating at age 3 years were generally taller after 12 months versus 9 non-GH-treated patients. Mean annual growth velocity significantly increased from age 2 to 3 versus 3 to 4 years in GH-treated patients (4.37 vs. 7.23 cm/year; p = 0.0014), but not in non-GH-treated patients (4.94 vs. 4.20 cm/year). The mean height at age 4 years with/without GH was 83.6/79.8 cm. These results improve our understanding of young patients with ACH in Japan and confirm that early diagnosis of ACH and monitoring of complications help facilitate appropriate interventions.

A scoping review of nutrition issues and management strategies in individuals with skeletal dysplasia

PURPOSE

Skeletal dysplasia are heterogeneous conditions affecting the skeleton. Common nutrition issues include feeding difficulties, obesity, and metabolic complications. This systematic scoping review aimed to identify key nutrition issues, management strategies, and gaps in knowledge regarding nutrition in skeletal dysplasia.

METHODS

The databases Ovid MEDLINE, Ovid EMBASE, Ebsco CINAHL, Scopus, and Cochrane Central Register of Controlled Trials and Database of Systematic Reviews were searched. Reference lists and citing literature for included studies were searched. Eligible studies included participants with skeletal dysplasia and described: anthropometry, body composition, nutrition-related biochemistry, clinical issues, dietary intake, measured energy or nutrition requirements, or nutrition interventions.

RESULTS

The literature search identified 8509 references from which 138 studies were included (130 observational, 3 intervention, 2 systematic reviews, and 3 clinical guidelines). Across 17 diagnoses identified, most studies described osteogenesis imperfecta (n = 50) and achondroplasia or hypochondroplasia (n = 47). Nutrition-related clinical issues, biochemistry, obesity, and metabolic complications were most commonly reported, and few studies measured energy requirements (n = 5).

CONCLUSION

Nutrition-related comorbidities are documented in skeletal dysplasia; yet, evidence to guide management is scarce. Evidence describing nutrition in rarer skeletal dysplasia conditions is lacking. Advances in skeletal dysplasia nutrition knowledge is needed to optimize broader health outcomes.

Evaluation of polysomnography findings in children with genetic skeletal disorders

Children with genetic skeletal disorders have variable conditions that can lead to sleep-disordered breathing, and polysomnography is the gold standard for diagnosing this condition. We aimed to review polysomnography findings, to assess the severity of sleep apnea, and to investigate the clinical variables predictive of sleep-disordered breathing in these patients. We retrospectively collected the medical records of patients with genetic skeletal disorders who underwent polysomnography for 5 years. Twenty-seven children with various genetic skeletal disorders, including achondroplasia (14), Crouzon syndrome (3), acromesomelic dysplasia Maroteaux type (3), Apert syndrome (2), osteopetrosis (1), Jeune dysplasia (1), Desbuquois dysplasia (1), acrodysostosis (1), and spondyloepiphyseal dysplasia (1) were enrolled. The median age at the first polysomnography was 58 (1st-3rd quartile: 31-113) months. The overall sleep-disordered breathing results were: 19 (70.3%) had obstructive sleep apneas (OSA) (4 mild, 6 moderate, 9 severe), 2 (7.4%) had central apneas, 4 (14.8%) had nocturnal hypoventilation. There was a significant correlation between non-ambulatory status with both total AHI and OSA (p < 0.001, rho: -0.66/p = 0.04, rho: 0.38, respectively). Nine patients received positive airway pressure titration, and the oAHI values of all returned to the normal range. These patients were started with positive airway pressure treatment. Our cohort showed that the majority of the patients with skeletal dysplasia had sleep apnea syndrome characterised mainly by OSA, highlighting the importance of polysomnography screening for sleep disorders. Positive airway pressure therapy represents an effective treatment for sleep-disordered breathing in those patients.

Pediatric Sleep Respiratory Disorders: A Narrative Review of Epidemiology and Risk Factors

Sleep is a fundamental biological necessity, the lack of which has severe repercussions on the mental and physical well-being in individuals of all ages. The phrase "sleep-disordered breathing (SDB)" indicates a wide array of conditions characterized by snoring and/or respiratory distress due to increased upper airway resistance and pharyngeal collapsibility; these range from primary snoring to obstructive sleep apnea (OSA) and occur in all age groups. In the general pediatric population, the prevalence of OSA varies between 2% and 5%, but in some particular clinical conditions, it can be much higher. While adenotonsillar hypertrophy ("classic phenotype") is the main cause of OSA in preschool age (3-5 years), obesity ("adult phenotype") is the most common cause in adolescence. There is also a "congenital-structural" phenotype that is characterized by a high prevalence of OSA, appearing from the earliest ages of life, supported by morpho-structural abnormalities or craniofacial changes and associated with genetic syndromes such as Pierre Robin syndrome, Prader-Willi, achondroplasia, and Down syndrome. Neuromuscular disorders and lysosomal storage disorders are also frequently accompanied by a high prevalence of OSA in all life ages. Early recognition and proper treatment are crucial to avoid major neuro-cognitive, cardiovascular, and metabolic morbidities.

Comprehensive literature review on the prevalence of comorbid conditions in patients with achondroplasia

BACKGROUND

Achondroplasia (ACH) is a rare, genetic condition and is the most common skeletal dysplasia resulting in disproportionate short stature and numerous multi-systemic comorbidities. As we enter an era of new treatment options which may impact comorbidities, it is important to understand the background rates of these events to aid evaluation of potential treatment effects. Thus, the aim of this literature review was to provide a comprehensive quantification of prevalence estimates of comorbidities in achondroplasia by age for use as a compiled reference to assist in quantifying the risk/benefit of new treatment options and informing timely management of ACH.

METHODS

PubMed and Embase databases were searched, complemented by manual bibliography searching, for peer-reviewed articles published between 1975 and 2021, guided by PRISMA principles. Number of patients and the prevalence of specific comorbidities by age were extracted. We calculated exact 95 %-confidence limits for the proportion of affected patients (prevalence) and data were presented visually using forest plots. An a priori decision was made not to utilise meta-analytic techniques to pool estimates as we intended to understand the variability in comorbidities by displaying each estimate separately.

RESULTS

The literature search identified 206 articles of which 73 were eligible for inclusion. The majority of studies (n = 34) had been conducted in the USA or in Europe (n = 20). Study designs were mostly retrospective chart reviews (n = 33) or small cohort studies (n = 19). The availability of literature on particular conditions varied but trended towards a focus on assessment and prevention of severe conditions, such as respiratory conditions in children (21 studies), neurological manifestations (16 studies) and upper spine compression (15 studies). There was substantial heterogeneity in study design, type of clinical setting, populations and use of definitions in reporting comorbidities which need to be considered when interpreting study results. Despite the variability of the studies, comorbidity patterns by age were recognizable. In infants, a high prevalence (>20 %) was found for kyphosis, a range of neurological manifestations and sleep apnea. There was also an excess mortality in infancy (4-7.8/100 person-years). Conditions identified in infancy continued to prevail in childhood. Genu varum was highly prevalent from the age children started to walk (9-75 %). Other conditions started to emerge in children; those with a high prevalence (>20 %) were hearing loss and pain. In adolescence, neurological manifestations in the arm, neck or leg were reported (~15 %), consistent with symptomatic spinal stenosis or spinal compression. Fewer studies were available in older populations, especially in adults; however limited data suggest that pain and cardiovascular conditions, particularly excess weight and obesity, became more prevalent into adulthood. Mortality rates increased again in older age-groups.

CONCLUSION

This review provides a reference base of current knowledge of the type and frequency of comorbidities in ACH. This not only allows future contextualisation of new treatment options but supports clinical decision-making on the timely medical management and intervention of ACH. This review also reflects the current medical priorities in the management of ACH, indicating a focus on pediatric care and the complex needs of individuals with ACH involving many different disciplines. Further studies into the natural history of this rare disease using more consistent definitions of comorbidities, especially into adulthood, are needed to elucidate the multi-systemic nature of this condition.

Airways and craniofacial assessment in children affected by achondroplasia with and without sleep-disordered breathing: quantitative magnetic resonance study

PURPOSE

To identify MRI-based quantitative craniofacial variables linked to airways narrowing and obstructive sleep apnea (OSA) development in children with achondroplasia.

METHODS

We evaluated skull base and midface MRI in two cohorts of children affected by achondroplasia, with (group 1) or without OSA (group 2). 3DFSPGR-T1weighted images were used to assess airways volume (nasopharynx, oropharynx, and laryngopharynx), jugular foramina (JF) and hypoglossal foramina (HF) areas, foramen magnum area, cervical cord area, and maxillary retrusion (SNA angle).

RESULTS

Nineteen out of 27 children with achondroplasia exhibited different degrees of obstructive respiratory impairment (n.4 mild, n.8 moderate, n.7 severe), while 8 children did not show OSA. Each group was compared with age-matched controls without neuroimaging abnormalities. Both groups showed reduced nasopharynx volume, JF areas, and SNA angle, while group 1 showed also reduced oropharynx volume, ratio of FM/cervical cord areas, and HF areas (p < 0.05). A positive correlation between nasopharynx volume and SNA angle was found in both groups, while a positive correlation among upper airways volume, JF and HF areas was found only in group 1. No correlation between upper airways volume and OSA severity was found.

CONCLUSION

In children with achondroplasia, multifaced craniofacial abnormalities contribute to airways volume reduction predisposing to sleep disordered breathing. MRI-based quantitative assessment allows the appraisal of craniofacial variables linked to the development of sleep-disordered breathing such as FM stenosis, jugular and hypoglossal foramina stenosis, and retruded maxillary position and may be a valuable tool for clinical surveillance.

International Consensus Statement on the diagnosis, multidisciplinary management and lifelong care of individuals with achondroplasia

Achondroplasia, the most common skeletal dysplasia, is characterized by a variety of medical, functional and psychosocial challenges across the lifespan. The condition is caused by a common, recurring, gain-of-function mutation in FGFR3, the gene that encodes fibroblast growth factor receptor 3. This mutation leads to impaired endochondral ossification of the human skeleton. The clinical and radiographic hallmarks of achondroplasia make accurate diagnosis possible in most patients. However, marked variability exists in the clinical care pathways and protocols practised by clinicians who manage children and adults with this condition. A group of 55 international experts from 16 countries and 5 continents have developed consensus statements and recommendations that aim to capture the key challenges and optimal management of achondroplasia across each major life stage and sub-specialty area, using a modified Delphi process. The primary purpose of this first International Consensus Statement is to facilitate the improvement and standardization of care for children and adults with achondroplasia worldwide in order to optimize their clinical outcomes and quality of life.

The (extended) achondroplasia foramen magnum score has good observer reliability

BACKGROUND

Achondroplasia is the most common skeletal dysplasia. A significant complication is foramen magnum stenosis. When severe, compression of the spinal cord may result in sleep apnea, sudden respiratory arrest and death. To avoid complications, surgical decompression of the craniocervical junction is offered in at-risk cases. However, practice varies among centres. To standardize magnetic resonance (MR) reporting, the achondroplasia foramen magnum score was recently developed. The reliability of the score has not been assessed.

OBJECTIVE

To assess the interobserver reliability of the achondroplasia foramen magnum score.

MATERIALS AND METHODS

Base of skull imaging of children with achondroplasia under the care of Sheffield Children's Hospital was retrospectively and independently reviewed by four observers using the achondroplasia foramen magnum score. Two-way random-effects intraclass coefficient (ICC) was used to assess inter- and intra-observer reliability.

RESULTS

Forty-nine eligible cases and five controls were included. Of these, 10 were scored normal, 17 had a median score of 1 (mild narrowing), 11 had a median score of 2 (effacement of cerebral spinal fluid), 10 had a score of 3 (compression of cord) and 6 had a median score of 4 (cord myelopathic change). Interobserver ICC was 0.72 (95% confidence interval = 0.62-0.81). Intra-observer ICC ranged from 0.60 to 0.86. Reasons for reader disagreement included flow void artefact, subtle T2 cord signal and myelopathic T2 cord change disproportionate to canal narrowing.

CONCLUSION

The achondroplasia foramen magnum score has good interobserver reliability. Imaging features leading to interobserver disagreement have been identified. Further research is required to prospectively validate the score against clinical outcomes.

ERS Statement on pediatric long term noninvasive respiratory support

Long term noninvasive respiratory support, comprising continuous positive airway pressure (CPAP) and noninvasive ventilation (NIV), in children is expanding worldwide, with increasing complexities of children being considered for this type of ventilator support and expanding indications such as palliative care. There have been improvements in equipment and interfaces. Despite growing experience, there are still gaps in a significant number of areas: there is a lack of validated criteria for CPAP/NIV initiation, optimal follow-up and monitoring; weaning and long term benefits have not been evaluated. Therapeutic education of the caregivers and the patient is of paramount importance, as well as continuous support and assistance, in order to achieve optimal adherence. The preservation or improvement of the quality of life of the patient and caregivers should be a concern for all children treated with long term CPAP/NIV. As NIV is a highly specialised treatment, patients are usually managed by an experienced pediatric multidisciplinary team. This Statement written by experts in the field of pediatric long term CPAP/NIV aims to emphasize on the most recent scientific input and should open up to new perspectives and research areas.

Otolaryngology Utilization in Patients With Achondroplasia: Results From the CLARITY Study

OBJECTIVES/HYPOTHESIS

To quantify otolaryngologic surgery utilization in patients with achondroplasia, and to identify any changes in utilization over the past four decades.

STUDY DESIGN

Retrospective cohort study.

METHODS

A retrospective cohort study of 1,374 patients with achondroplasia enrolled in the CLARITY retrospective cohort study at four centers of multi-specialty care for patients with achondroplasia. Otolaryngologic surgeries are presented by birth cohort decade. The main outcomes were number of primary and additional otolaryngologic procedures; age at surgery; likelihood of repeated surgery; temporal trends in surgical utilization.

RESULTS

In this cohort of 1,374 patients with achondroplasia, 620 (45.1%) had pharyngeal surgery at least once, 150 (10.9%) had pharyngeal surgery on more than one occasion, and patients who had adenoidectomy first were 2.68 times more likely to require a second pharyngeal surgery than those who had adenotonsillectomy. Seven hundred and seventy-nine (56.7%) had tympanostomy tubes placed at least once, and 447 (32.5%) had tympanostomy tubes placed more than one time. Age at first pharyngeal surgery decreased by 1.2 years per birth cohort decade, and age at tympanostomy tube placement decreased by 1.1 years per decade.

CONCLUSIONS

Patients with achondroplasia often require otolaryngologic surgery, particularly adenoidectomy and/or tonsillectomy as well as tympanostomy tube placement. Such surgery is performed now more frequently and at younger ages than in earlier decades. While otolaryngologic disease associated with achondroplasia is now recognized earlier and treated more frequently, long-term outcome studies are needed.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Sleep-Disordered Breathing and Cardiovascular Disease in Children and Adolescents: A Scientific Statement From the American Heart Association

Obstructive sleep apnea (OSA) is a known risk factor for cardiovascular disease in adults. It is associated with incident systemic hypertension, arrhythmia, stroke, coronary artery disease, and heart failure. OSA is common in children and adolescents, but there has been less focus on OSA as a primary risk factor for cardiovascular disease in children and adolescents. This scientific statement summarizes what is known regarding the impact of sleep‐disordered breathing and, in particular, OSA on the cardiovascular health of children and adolescents. This statement highlights what is known regarding the impact of OSA on the risk for hypertension, arrhythmia, abnormal ventricular morphology, impaired ventricular contractility, and elevated right heart pressure among children and adolescents. This scientific statement also summarizes current best practices for the diagnosis and evaluation of cardiovascular disease–related complications of OSA in children and adolescents with sleep apnea and highlights potential future research in the area of sleep‐disordered breathing and cardiovascular health during childhood and adolescence.

Obstructing Sleep Apnea in Children with Genetic Disorders-A Special Need for Early Multidisciplinary Diagnosis and Treatment

Background—Children with genetic disorders have multiple anatomical and physiological conditions that predispose them to obstructive sleep apnea syndrome (OSAS). They should have priority access to polysomnography (PSG) before establishing their therapeutic protocol. We analyzed the prevalence and the severity of OSAS in a particular group of children with genetic disorders and strengthened their need for a multidisciplinary diagnosis and adapted management. Methods—The retrospective analysis included children with genetic impairments and sleep disturbances that were referred for polysomnography. We collected respiratory parameters from sleep studies: apnea–hypopnea index (AHI), SatO₂ nadir, end-tidal CO₂, and transcutaneous CO₂. Subsequent management included non-invasive ventilation (NIV) or otorhinolaryngological (ENT) surgery of the upper airway. Results—We identified 108 patients with neuromuscular disorders or multiple congenital anomalies. OSAS was present in 87 patients (80.5%), 3 of whom received CPAP, 32 needed another form of NIV during sleep, and 15 patients were referred for ENT surgery. The post-therapeutic follow-up PSG parameters confirmed the success of the treatment. Conclusions—The upper airway obstruction diagnostics and management for children with complex genetic diseases need a multidisciplinary approach. Early detection and treatment of sleep-disordered breathing in children with genetic disorders is a priority for improving their quality of life.

Lifetime impact of achondroplasia: Current evidence and perspectives on the natural history

Achondroplasia, the most common form of disproportionate short stature, is caused by a variant in the fibroblast growth factor receptor 3 (FGFR3) gene. Advances in drug treatment for achondroplasia have underscored the need to better understand the natural history of this condition. This article provides a critical review and discussion of the natural history of achondroplasia based on current literature evidence and the perspectives of clinicians with extensive knowledge and practical experience in managing individuals with this diagnosis. This review draws evidence from recent and ongoing longitudinal natural history studies, supplemented with relevant cross-sectional studies where longitudinal research is lacking, to summarize the current knowledge on the nature, incidence, chronology, and interrelationships of achondroplasia-related comorbidities across the lifespan. When possible, data related to adults are presented separately from data specific to children and adolescents. Gaps in knowledge regarding clinical care are identified and areas for future research are recommended and discussed.

Obstructive sleep apnea in Norwegian adults with achondroplasia: a population-based study

Background

Previous studies have found a high prevalence of obstructive sleep apnea (OSA) in children with achondroplasia, but clinical studies on this complication in adults with achondroplasia are lacking.

Objectives

This population-based, cross-sectional study investigated the prevalence, severity, and predictive factors of OSA in Norwegian adults with achondroplasia.

Methods

We collected clinical data on 49 participants. Participants without a preexisting diagnosis of OSA had an overnight sleep registration. OSA was defined as an apnea–hypopnea index (AHI) ≥ 5 plus characteristic clinical symptoms, or AHI ≥ 15. We used the Berlin Questionnaire to assess clinical symptoms of OSA.

Results

OSA was found in 59% (29/49) of the participants (95% confidence interval 44 to 73%), of whom 59% (17/29) had moderate to severe OSA (AHI ≥ 15), and 48% (14/29) were previously undiagnosed. Variables predictive of OSA were: excessive daytime sleepiness; unrested sleep; loud snoring; observed nocturnal breathing stops; hypertension; age > 40 years; and BMI > 30 kg/m².

Conclusion

OSA was highly prevalent in Norwegian adults with achondroplasia, which we believe is representative of this population worldwide. Follow-up of adults with achondroplasia should include assessment of symptoms and signs of OSA, with a low threshold for conducting an overnight sleep registration if findings suggestive of OSA are present.

Management of obstructive sleep apnea in children with achondroplasia: Outcomes of surgical interventions

INTRODUCTION

Children with achondroplasia are predisposed to obstructive sleep apnea (OSA), however little is known regarding surgical interventions and outcomes for this condition. The aim of this study was to evaluate the severity of OSA in children with achondroplasia and report outcomes of surgical interventions using polysomnography (PSG) parameters.

METHODS

Retrospective chart review of children with achondroplasia with documented OSA from 2002 to 2018 that had pre- and post-operative PSG results. Additional data extracted included age, gender, and type of surgical interventions. The primary outcome was change in postoperative obstructive apnea hypopnea index (OAHI).

RESULTS

Twenty-two children with achondroplasia were identified that underwent formal PSG before and after confirmed OSA. The median age was 12 months (range 4 days-15.3 years, IQR 2 years) at time of initial PSG evaluation. The majority (72.7%) of patients had severe OSA with a median preoperative OAHI of 14.25 (IQR 9.4). The most common surgical intervention was adenotonsillectomy (n = 15). Multilevel surgical intervention was required in 9 (41.0%) patients. Post-operatively, 16 (72.7%) children experienced a reduction in OAHI, of which four (18.2%) had complete OSA resolution. OAHI scores increased in six (27.3%) children. Patients with the most severe OSA at baseline had greater improvements in post-operative OAHI (P < 0.01). Neither type nor number of surgical interventions was associated with improved outcomes (P = 0.51, P = 0.89 respectively).

CONCLUSIONS

Treatment of OSA in children with achondroplasia remains challenging. Although reduction of OAHI is possible, caregivers should be counseled about the likelihood of persistent OSA and the potential for multilevel airway surgery.

Birth prevalence of achondroplasia: A systematic literature review and meta-analysis

Achondroplasia is a genetic disorder that results in disproportionate short stature. The true prevalence of achondroplasia is unknown as estimates vary widely. This systematic literature review and meta‐analysis was conducted to better estimate worldwide achondroplasia birth prevalence. PubMed, Embase, Scielo, and Google Scholar were searched, complemented by manual searching, for peer‐reviewed articles published between 1950 and 2019. Eligible articles were identified by two independent researchers using predefined selection criteria. Birth prevalence estimates were extracted for analysis, and the quality of evidence was assessed. A meta‐analysis using a quality effects approach based on the inverse variance fixed effect model was conducted. The search identified 955 unique articles, of which 52 were eligible and included. Based on the meta‐analysis, the worldwide birth prevalence of achondroplasia was estimated to be 4.6 per 100,000. Substantial regional variation was observed with a considerably higher birth prevalence reported in North Africa and the Middle East compared to other regions, particularly Europe and the Americas. Higher birth prevalence was also reported in specialized care settings. Significant heterogeneity (Higgins I² of 84.3) was present and some indication of publication bias was detected, based on visual asymmetry of the Doi plot with a Furuya‐Kanamori index of 2.73. Analysis of pooled data from the current literature yields a worldwide achondroplasia birth prevalence of approximately 4.6 per 100,000, with considerable regional variation. Careful interpretation of these findings is advised as included studies are of broadly varying methodological quality.

Prophylactic Decompression for Cervical Stenosis in Jeune Syndrome: Report From a Single Institution

STUDY DESIGN

This is a level IV retrospective descriptive study at a single institution.

OBJECTIVE

The objective of the study was to determine the preoperative signs or symptoms prompting cervicomedullary imaging in Jeune syndrome.

SUMMARY OF BACKGROUND DATA

Jeune syndrome is a rare autosomal recessive disorder that results in pulmonary compromise from abnormal development of the thorax. Multiple medical comorbidities complicate timely diagnosis of cervicomedullary stenosis, which neurologically jeopardizes this patient population with regards to improper cervical manipulation. Currently, explicit screening of the cervicomedullary junction is not advocated in national guidelines.

METHODS

The User Reporting Workbench and Center for Thoracic Insufficiency Syndrome (CTIS) Safety Registry was queried for patients with Jeune syndrome under the age of 18 with cervicomedullary stenosis with or without suboccipital craniectomy/craniotomy evaluated at the authors' institution from January 1, 2007 to August 21, 2018. The primary outcome was the clinical reason for cervicomedullary screening. Secondary outcomes were: age at time of surgery, preoperative myelopathy (spasticity, urinary retention), hydrocephalus, postoperative deficits (respiratory, motor, swallowing difficulty), and need for cervical fusion.

RESULTS

Of 32 patients with Jeune syndrome, four (12.5%) had cervicomedullary stenosis requiring decompression. The average age at surgery was 5.25 months (2-9 mo). Two patients underwent imaging due to desaturation events while the other two patients were diagnosed with cervical stenosis as an incidental finding. No patients exhibited clinical myelopathy. Two patients had baseline preoperative swallowing difficulties. None of the patients postoperatively required cervical fusions, nor did they exhibit respiratory deficits, motor deficits, or worsening swallowing difficulties.

CONCLUSION

Jeune patients should be routinely screened for cervicomedullary stenosis and undergo subsequent prophylactic decompression to minimize or eliminate the development of irreversible neurologic compromise.

LEVEL OF EVIDENCE

4.

Clinical Practice Guidelines for Achondroplasia

Achondroplasia (ACH) is a skeletal dysplasia that presents with limb shortening, short stature, and characteristic facial configuration. ACH is caused by mutations of the FGFR3 gene, leading to constantly activated FGFR3 and activation of its downstream intracellular signaling pathway. This results in the suppression of chondrocyte differentiation and proliferation, which in turn impairs endochondral ossification and causes short-limb short stature. ACH also causes characteristic clinical symptoms, including foramen magnum narrowing, ventricular enlargement, sleep apnea, upper airway stenosis, otitis media, a narrow thorax, spinal canal stenosis, spinal kyphosis, and deformities of the lower extremities. Although outside Japan, papers on health supervision are available, they are based on reports and questionnaire survey results. Considering the scarcity of high levels of evidence and clinical guidelines for patients with ACH, clinical practical guidelines have been developed to assist both healthcare professionals and patients in making appropriate decisions in specific clinical situations. Eleven clinical questions were established and a systematic literature search was conducted using PubMed/MEDLINE. Evidence-based recommendations were developed, and the guidelines describe the recommendations related to the clinical management of ACH. We anticipate that these clinical practice guidelines for ACH will be useful for healthcare professionals and patients alike.

Long Term Continuous Positive Airway Pressure and Non-invasive Ventilation in Obstructive Sleep Apnea in Children With Obesity and Down Syndrome

This review will focus on non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP) therapy in children with obstructive sleep apnea (OSA) due to obesity and underlying syndromes. These children have a high prevalence of OSA and residual OSA after adenotonsillectomy. Therefore, a high proportion of these children are treated with CPAP or NIV. This review will focus on treatment selection tools and will subsequently cover specific issues on CPAP treatment in obese and syndromic children with a major focus on Down syndrome.

Non-invasive Ventilation and CPAP Failure in Children and Indications for Invasive Ventilation

Non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP) are effective treatments for children with severe sleep disordered breathing (SBD). However, some patients may present too severe SDB that do not respond to NIV/CPAP or insufficient compliance to treatment. A careful revaluation of the interface and of ventilator settings should be performed before considering alternative treatments. In patients with obstructive sleep apnea (OSA), alternatives to CPAP/NIV rely on the underlying disease. Ear-nose-throat (ENT) surgery such as adeno-tonsillectomy (AT), turbinectomy or supraglottoplasty represent an effective treatment in selected patients before starting CPAP/NIV and should be reconsidered in case of CPAP failure. Rapid maxillary expansion (RME) is restricted to children with OSA and a narrow palate who have little adenotonsillar tissue, or for those with residual OSA after AT. Weight loss is the first line therapy for obese children with OSA before starting CPAP and should remain a priority in the long-term. Selected patients may benefit from maxillo-facial surgery such as mandibular distraction osteogenesis (MDO) or from neurosurgery procedures like fronto-facial monobloc advancement. Nasopharyngeal airway (NPA) or high flow nasal cannula (HFNC) may constitute efficient alternatives to CPAP in selected patients. Hypoglossal nerve stimulation has been proposed in children with Down syndrome not tolerant to CPAP. Ultimately, tracheostomy represents the unique alternative in case of failure of all the above-mentioned treatments. All these treatments require a multidisciplinary approach with a personalized treatment tailored on the different diseases and sites of obstruction. In patients with neuromuscular, neurological or lung disorders, non-invasive management in case of NIV failure is more challenging. Diaphragmatic pacing has been proposed for some patients with central congenital hypoventilation syndrome (CCHS) or neurological disorders, however its experience in children is limited. Finally, invasive ventilation via tracheotomy represents again the ultimate alternative for children with severe disease and little or no ventilatory autonomy. However, ethical considerations weighting the efficacy against the burden of this treatment should be discussed before choosing this last option.

Current knowledge of medical complications in adults with achondroplasia: A scoping review

This article provides an overview of the current knowledge on medical complications, health characteristics, and psychosocial issues in adults with achondroplasia. We have used a scoping review methodology particularly recommended for mapping and summarizing existing research evidence, and to identify knowledge gaps. The review process was conducted in accordance with the PRISMA‐ScR guidelines (Preferred Reporting Items for Systematic reviews and Meta‐Analyses Extension for Scoping Reviews). The selection of studies was based on criteria predefined in a review protocol. Twenty‐nine publications were included; 2 reviews, and 27 primary studies. Key information such as reference details, study characteristics, topics of interest, main findings and the study author's conclusion are presented in text and tables. Over the past decades, there has only been a slight increase in publications on adults with achondroplasia. The reported morbidity rates and prevalence of medical complications are often based on a few studies where the methodology and representativeness can be questioned. Studies on sleep‐related disorders and pregnancy‐related complications were lacking. Multicenter natural history studies have recently been initiated. Future studies should report in accordance to methodological reference standards, to strengthen the reliability and generalizability of the findings, and to increase the relevance for implementing in clinical practice.

Polysomnography as an indicator for cervicomedullary decompression to treat foramen magnum stenosis in achondroplasia

OBJECTIVE

Management of cervicomedullary compression due to foramen magnum stenosis in achondroplasia remains controversial, especially for patients with no symptoms or mild symptoms. We examined the effectiveness of polysomnography (PSG) as an indicator for cervicomedullary decompression treatment.

METHODS

We retrospectively reviewed nine achondroplasia cases (mean age 1 year and 9 months) treated from 2008 to 2015. All patients were examined by PSG, magnetic resonance imaging (MRI), and otolaryngeal fibroscopy. We analyzed demographic data, clinical presentation, degree and type of respiratory impairment, severity of foramen magnum stenosis and concomitant cervicomedullary compression, treatment (conservative or surgical), and clinical outcome.

RESULTS

Eight of nine patients presented with no severe symptoms in the daytime. However, MRI revealed four severe, four moderate, and one mild case of cervicomedullary compression, and PSG demonstrated severe sleep apnea in four cases and moderate sleep apnea in five cases. All sleep apnea cases were obstructive or obstructive-dominant. Fibroscopy revealed no upper airway stenosis in six cases and mild stenosis in three cases. Four patients who had severe sleep-related respiratory disturbance on PSG and severe or moderate cervicomedullary compression were treated by cervicomedullary decompression. Three of these patients demonstrated improved sleep respiration soon after surgery, while one required temporary tracheostomy due to bilateral vocal cord paralysis caused by compression during intratracheal intubation.

CONCLUSION

Polysomnography can be a useful indicator for cervicomedullary decompression surgery, especially in cases of seemingly asymptomatic achondroplasia with severe foramen magnum stenosis.

Sleep-disordered breathing in paediatric setting: existing and upcoming of the genetic disorders

Childhood obstructive sleep apnea syndrome (OSAS) is characterized by anatomical and functional upper airway abnormalities as pathophysiological determinants, and clinical symptoms are frequently clear. OSAS is widely described in rare genetic disorders, such as achondroplasia, Down syndrome, Prader-Willi syndrome, Pierre Robin sequence, and mucopolysaccharidosis. Craniofacial and upper airway involvement is frequently morbid conditions. In children with genetic diseases, the clinical symptoms of OSAS are often slight or absent, and related morbidities are usually more severe and can be observed at any age. The present review is aimed to updating the discoveries regarding OSAS on Achondroplasia, Down syndrome, Prader-Willi syndrome, Pierre Robin sequence, Sickle cell disease, or encountered in our clinical practice (Ehlers-Danlos syndrome, Ellis-van Creveld syndrome, Noonan syndrome). Two additional groups of genetic disorders will be focused (mucopolysaccharidoses and osteogenesis imperfecta). The flowing items are covered for each disease: (I) what is the pathophysiology of OSAS? (II) What is the incidence/prevalence of OSAS? (III) What result from the management and prognosis? (IV) What are the recommendations? Considering the worries of OSAS, such as inattention and behavioural problems, daytime sleepiness, failure to thrive, cardiological and metabolic complications, the benefit of a widespread screening and the treatment in children with genetic diseases is undoubtful. The goals of the further efforts can be the inclusion of various genetic diseases into guidelines for the screening of OSAS, updating the shreds of evidence based on the research progression.

Long-term Non-Invasive Ventilation in Infants: A Systematic Review and Meta-Analysis

BACKGROUND

The use of long-term non-invasive ventilation (NIV) to treat sleep and breathing disorders in children has increased substantially in the last decade; however, less data exist about its use in infants. Given that infants have distinct sleep and breathing patterns when compared to older children, the outcomes of infants on long-term NIV may differ as well. The aim of this study is to systematically review the use and outcomes of long-term NIV in infants.

METHODS

Ovid Medline, Ovid Embase, CINAHL (via EbscoHOST), PubMed, and Wiley Cochrane Library were systematically searched from January 1990 to July 2017. Studies on infants using long-term NIV outside of an acute care setting were included. Data were extracted on study design, population characteristics, and NIV outcomes.

RESULTS

A total of 327 studies were full-text reviewed, with final inclusion of 60. Studies were distributed across airway (40%), neuromuscular (28%), central nervous system (10%), cardio-respiratory (2%), and multiple (20%) disease categories. Of the 18 airway studies reporting on NIV outcomes, 13 (72%) reported improvements in respiratory parameters. Of the 12 neuromuscular studies exclusively on spinal muscular atrophy type 1 (SMA1), six (50%) reported decreased hospitalizations and nine (75%) reported on mortality outcomes. Risk of bias was moderate to serious, and quality of the evidence was low to very low for all studies. Most studies had an observational design with no control group, limiting the potential for a meta-analysis.

CONCLUSION

The outcomes reported in studies differed by the disease category being studied. Studies on airway conditions showed improvements in respiratory parameters for infants using NIV. Studies on neuromuscular disorder, which were almost exclusively on SMA1, reported decreased hospitalizations and prolonged survival. Overall, it appears that NIV is an effective long-term therapy for infants. However, the high risk of bias and low quality of the available evidence limited strong conclusions.

Sleep-Disordered Breathing in Children with Rare Skeletal Disorders: A Survey of Clinical Records

OBJECTIVE

Craniofacial disharmony in skeletal diseases is strongly associated with sleep-disordered breathing. This study was aimed at studying the sleep respiratory patterns in young children with rare skeletal disorders.

DESIGN

This retrospective study included children with achondroplasia (ACH), osteogenesis imperfecta (OI) and Ellis van Creveld Syndrome. Our subjects underwent an in-laboratory overnight respiratory polygraph between January 2012 and April 2016. All medical records were reviewed and brain Magnetic Resonance Imaging was conducted on patients with ACH, nasopharynx, oropharynx and laryngopharynx spaces.

PATIENTS

Twenty-four children were enrolled, 13 with ACH, 2 with spondyloepiphyseal dysplasia, 1 with odontochondrodysplasia, 6 with OI and 2 with Ellis van Creveld Syndrome.

RESULTS

Children with ACH, who had adenotonsillectomy, showed fewer sleep respiratory involvement than untreated children. Among 13 patients with ACH, brain magnetic resonance imaging was available in 10 subjects and significant negative correlation was found between sleep respiratory patterns, nasopharynx and oropharynx space (p < 0.05). In 2 patients with spondyloepiphyseal dysplasia, mild-to-moderate sleep respiratory involvement was found. Both subjects had a history of adenotonsillectomy. Mild sleep respiratory involvement was also observed in 4 out of 6 patients with OI. One patient with Ellis van Creveld syndrome had mild sleep respiratory disturbance.

CONCLUSIONS

Sleep respiratory disturbances were detected in children with ACH, and with less severity also in OI and Ellis van Creveld syndrome. Adenotonsillectomy was successful in ACH in reducing symptoms. In light of our findings, multicenter studies are needed to obtain further information on these rare skeletal diseases.

ERS statement on obstructive sleep disordered breathing in 1- to 23-month-old children

The present statement was produced by a European Respiratory Society Task Force to summarise the evidence and current practice on the diagnosis and management of obstructive sleep disordered breathing (SDB) in children aged 1-23 months. A systematic literature search was completed and 159 articles were summarised to answer clinically relevant questions. SDB is suspected when symptoms or abnormalities related to upper airway obstruction are identified. Morbidity (pulmonary hypertension, growth delay, behavioural problems) and coexisting conditions (feeding difficulties, recurrent otitis media) may be present. SDB severity is measured objectively, preferably by polysomnography, or alternatively polygraphy or nocturnal oximetry. Children with apparent upper airway obstruction during wakefulness, those with abnormal sleep study in combination with SDB symptoms (e.g. snoring) and/or conditions predisposing to SDB (e.g. mandibular hypoplasia) as well as children with SDB and complex conditions (e.g. Down syndrome, Prader-Willi syndrome) will benefit from treatment. Adenotonsillectomy and continuous positive airway pressure are the most frequently used treatment measures along with interventions targeting specific conditions (e.g. supraglottoplasty for laryngomalacia or nasopharyngeal airway for mandibular hypoplasia). Hence, obstructive SDB in children aged 1-23 months is a multifactorial disorder that requires objective assessment and treatment of all underlying abnormalities that contribute to upper airway obstruction during sleep.

Adenotonsillectomy to treat obstructive sleep apnea: Is it enough?

Although adenotonsillectomy is the first line treatment for children with obstructive sleep apnea syndrome (0SAS),¹ improvement in objectively documented outcomes is often inadequate and a substantial number of children have residual disease. Early recognition and treatment of children with persistent OSAS is required to prevent long-term morbidity. The management of these children is frequently complex and a multidisciplinary approach is required as most of them have additional risk factors for OSAS and comorbidities. In this paper, we first provide an overview of children at risk for persistent disease following adenotonsillectomy. Thereafter, we discuss different diagnostic modalities to evaluate the sites of persistent upper airway obstruction and the currently available treatment options. Pediatr Pulmonol. 2017;52:699-709. © 2016 Wiley Periodicals, Inc.

Current Care and Investigational Therapies in Achondroplasia

PURPOSE OF REVIEW

The goal of this review is to evaluate the management options for achondroplasia, the most common non-lethal skeletal dysplasia. This disease is characterized by short stature and a variety of complications, some of which can be quite severe.

RECENT FINDINGS

Despite several attempts to standardize care, there is still no widely accepted consensus. This is in part due to absence of concrete data on the incidence of sudden unexplained death in infants with achondroplasia and the best investigation for ascertaining which individuals could benefit from foramen magnum decompression surgery. In this review, we identify the different options of care and management for the various orthopedic, neurologic, and respiratory complications. In parallel, several innovative or drug repositioning therapies are being investigated that would restore bone growth but may also prevent complications. Achondroplasia is the most common non-lethal skeletal dysplasia. It is characterized by short stature and a variety of complications, some of which can be quite severe. Despite several attempts to standardize care, there is still no widely accepted consensus. This is in part due to absence of concrete data on the incidence of sudden unexplained death in infants with achondroplasia and the best investigation for ascertaining which individuals could benefit from foramen magnum decompression surgery. In this review, we identify the different options of care and management for the various orthopedic, neurologic, and respiratory complications. In parallel, several innovative or drug repositioning therapies are being investigated that would restore bone growth but may also prevent complications.

Sleep-disordered breathing and its management in children with achondroplasia

Sleep-disordered breathing is a common feature in children with achondroplasia. The aim of our study was to review the poly(somno)graphic (P(S)G) findings and consequent treatments in children with achondroplasia followed in the national reference center for skeletal dysplasia. A retrospective review of the clinical charts and P(S)G of 43 consecutive children (mean age 3.9 ± 3.5 years) with achondroplasia seen over a period of 2 years was performed. Twenty four (59%) children had obstructive sleep apnea (OSA). Thirteen children had an obstructive apnea-hypopnea index (OAHI) < 5/hr, four had an OAHI between 5 and 10/hr, and seven had an OAHI ≥ 10/hr. Ten of the 15 children who had previous upper airway surgery still had an abnormal P(S)G. All the patients with an AHI ≥ 10/hr were under 7 years of age and none had a prior tonsillectomy. The children who underwent adeno-tonsillectomy, coupled in most cases with turbinectomy, were significantly older (mean age 7.5 ± 3.5 vs. 3.5 ± 1.7 years old, P = 0.015) and had significantly better P(S)G results than those who underwent only adeno-turbinectomy. No correlation was observed between the mean AHI value at the baseline P(S)G and the type of academic course (standard, supported or specialized). In conclusion, OSA is common in children with achondroplasia. The observation of a reduced prevalence of OSA after (adeno-)tonsillectomy is in favor of this type of surgery when possible.

Sleep disordered breathing in children with achondroplasia

BACKGROUND

Children with achondroplasia often have breathing problems, especially during sleep. The most important treatments are adenotonsillectomy (for treating upper obstruction) and/or neurosurgery (for resolving cervicomedullar junction stenosis).

DATA SOURCES

We reviewed the scientific literature on polysomnographic investigations which assessed the severity of respiratory disorders during sleep.

RESULTS

Recent findings have highlighted the importance of clinical investigations in patients with achondroplasia, differentiating between those that look for neurological patterns and those that look for respiratory problems during sleep. In particular, magnetic resonance imaging (MRI) and somatosensory evoked potentials are the main tools to evaluate necessary neurosurgery and over myelopathy, respectively.

CONCLUSIONS

The use of polysomnography enables clinicians to identify children with upper airway obstruction and to quantify disease severity; it is not suitable for MRI and/or neurosurgery considerations.

Obstructive sleep disordered breathing in 2- to 18-year-old children: diagnosis and management

This document summarises the conclusions of a European Respiratory Society Task Force on the diagnosis and management of obstructive sleep disordered breathing (SDB) in childhood and refers to children aged 2-18 years. Prospective cohort studies describing the natural history of SDB or randomised, double-blind, placebo-controlled trials regarding its management are scarce. Selected evidence (362 articles) can be consolidated into seven management steps. SDB is suspected when symptoms or abnormalities related to upper airway obstruction are present (step 1). Central nervous or cardiovascular system morbidity, growth failure or enuresis and predictors of SDB persistence in the long-term are recognised (steps 2 and 3), and SDB severity is determined objectively preferably using polysomnography (step 4). Children with an apnoea-hypopnoea index (AHI) >5 episodes·h(-1), those with an AHI of 1-5 episodes·h(-1) and the presence of morbidity or factors predicting SDB persistence, and children with complex conditions (e.g. Down syndrome and Prader-Willi syndrome) all appear to benefit from treatment (step 5). Treatment interventions are usually implemented in a stepwise fashion addressing all abnormalities that predispose to SDB (step 6) with re-evaluation after each intervention to detect residual disease and to determine the need for additional treatment (step 7).

Best practices in the evaluation and treatment of foramen magnum stenosis in achondroplasia during infancy

Achondroplasia is the most common inherited disorder of bone growth (skeletal dysplasia). Despite this fact, consistent and evidence-based management approaches to recognized, life-threatening complications, such as foramen magnum stenosis, are lacking. This study aims to outline best practice, based on evidence and expert consensus, regarding the diagnosis, assessment, and management of foramen magnum stenosis in achondroplasia during infancy. A panel of 11 multidisciplinary international experts on skeletal dysplasia was invited to participate in a Delphi process. They were: 1) presented with a list of 26 indications and a thorough literature review, 2) given the opportunity to anonymously rate the indications and discuss in face to face discussion; 3) edit the list and rate it in a second round. Those indications with more than 80% agreement were considered as consensual. After two rounds of rating and a face-to-face meeting, consensus was reached to support 22 recommendations for the evaluation and treatment of foramen magnum stenosis in infants with achondroplasia. These recommendations include indications for surgical decompression, ventriculomegaly, and hydrocephalus, sleep-disordered breathing, physical exams and the use of polysomnography and imaging in this condition. We present a consensus-based best practice guidelines consisting of 22 recommendations. It is hoped that these guidelines will lead to more uniform and structured evaluation, standardizing care pathways, and improving mortality and morbidity outcomes for this cohort.

Is there a correlation between sleep disordered breathing and foramen magnum stenosis in children with achondroplasia?

Children with achondroplasia have midface hypoplasia, frontal bossing, spinal stenosis, rhizomelia, and a small foramen magnum. Central sleep apnea, with potential resultant sudden death, is thought to be related to compression of the spinal cord at the cervicomedullary junction in these patients. Screening polysomnography and/or cervical spine MRI are often performed for infants with achondroplasia. Decompressive suboccipital craniectomy has been performed in selected cases. We aim to better delineate the relationship between polysomnography, cervical spine MRI, and indications for surgical decompression in achondroplasia.We retrospectively review electronic medical records of all children with achondroplasia in our IRB-approved skeletal dysplasia registry who had received screening polysomnography and cervical spine MRI examination was performed. We explored correlations of polysomnography, MRI parameters, and need for decompressive surgery. Seventeen patients with both polysomnography and MRI of the cervical spine met inclusion criteria. The average age at time of the sleep study was 2.4 ± 3.6 years. An abnormal apnea-hypopnea index was found in all patients, with central sleep apnea found in 6/17. Five patients (29%) required foramen magnum decompression. We found no statistically significant correlation between central sleep apnea and abnormal MRI findings suggestive of foramen magnum stenosis. Screening polysomnography is an important tool but does not appear to correlate with MRI findings of foramen magnum stenosis. Cord compression, with either associated T2 cord signal abnormality or clinical findings of clonus, was most predictive of subsequent surgical decompression.

Surgical treatment for cervicomedullary compression among infants with achondroplasia

PURPOSE

Achondroplasia is the most common form of dwarfism. Respiratory failure is responsible for most deaths among these children and is often related to cervicomedullary compression (CMC). We present our experience with early cervicomedullary decompression in infants with achondroplasia.

METHODS

Data was retrospectively collected for infants with achondroplasia who underwent CMC decompression between 1998 and 2013. Data included presurgical and postsurgical neurological examinations, MRI scans, and sleep study results.

RESULTS

Ten infants were included. Ages at surgery were 4 to 23 months (12.5 ± 6.88 months). All infants displayed neurological findings prior to surgery, although often subtle. All infants underwent a foramen magnum opening with a wide C1 laminectomy. Following surgery, seven patients (70 %) demonstrated improved neurological status, and one displayed neurological deterioration. Seven patients demonstrated improved sleep quality 1 year after surgery. These patients had a good or improved neurological status following surgery. Preoperative radiological findings included abnormal hyperintense T2 changes in all children (improved following surgery in six children), brainstem distortion in four children (improved in all), and diminished cerebrospinal fluid (CSF) spaces at the level of the foramen magnum in eight children (improved in seven). One child with extensive preoperative T2 changes accompanied by neurological and respiratory decline, deteriorated following surgery, and remains chronically ventilated.

CONCLUSIONS

Infants with achondroplasia are prone to neurological and respiratory symptoms. We believe that early diagnosis and early surgery for decompression of the foramen magnum and C1 lamina can alleviate respiratory symptoms, improve neurological status, and perhaps prevent sudden infant death in this population.

[Obstructive sleep apnea-hypopnea syndrome in children: beyond adenotonsillar hypertrophy]

The prevalence of obstructive sleep apnea-hypopnea syndrome in the general childhood population is 1-2% and the most common cause is adenotonsillar hypertrophy. However, beyond adenotonsillar hypertrophy, there are other highly prevalent causes of this syndrome in children. The causes are often multifactorial and include muscular hypotonia, dentofacial abnormalities, soft tissue hypertrophy of the airway, and neurological disorders). Collaboration between different specialties involved in the care of these children is essential, given the wide variability of conditions and how frequently different factors are involved in their genesis, as well as the different treatments to be applied. We carried out a wide literature review of other causes of obstructive sleep apnea-hypopnea syndrome in children, beyond adenotonsillar hypertrophy. We organised the prevalence of this syndrome in each pathology and the reasons that cause it, as well as their interactions and management, in a consistent manner.

Optimal management of complications associated with achondroplasia

Achondroplasia is the most common form of skeletal dysplasia, resulting in disproportionate short stature, and affects over 250,000 people worldwide. Individuals with achondroplasia demonstrate a number of well-recognized anatomical features that impact on growth and development, with a complex array of medical issues that are best managed through a multidisciplinary team approach. The complexity of this presentation, whereby individual impairments may impact upon multiple activity and participation areas, requires consideration and discussion under a broad framework to gain a more thorough understanding of the experience of this condition for individuals with achondroplasia. This paper examines the general literature and research evidence on the medical and health aspects of individuals with achondroplasia and presents a pictorial model of achondroplasia based on The International Classification of Functioning, Disability, and Health (ICF). An expanded model of the ICF will be used to review and present the current literature pertaining to the musculoskeletal, neurological, cardiorespiratory, and ear, nose, and throat impairments and complications across the lifespan, with discussion on the impact of these impairments upon activity and participation performance. Further research is required to fully identify factors influencing participation and to help develop strategies to address these factors.

Airway malacia in children with achondroplasia

This study was undertaken to assess the frequency of airway malacia in infants and young children with achondroplasia, a population well known to be at risk for a variety of respiratory problems. We also wished to evaluate what, if any, contribution airway malacia makes to the complex respiratory issues that may be present in those with achondroplasia. Retrospective chart review of all infants and young children with achondroplasia who were assessed through the Midwest Regional Bone Dysplasia Clinics from 1985 through 2012 (n = 236) was completed. Records of comprehensive clinical examinations, polysomnographic assessments, and airway visualization were reviewed and abstracted using a data collection form. Analyses were completed comparing the group with and those without evidence for airway malacia. Thirteen of 236 patients (5.5%) were found to have airway malacia. Most of those affected had lower airway involvement (9/13). The presence of airway malacia was correlated with an increased occurrence of obstructive sleep apnea as well as need for oxygen supplementation, airway surgeries and tracheostomy placement. Although estimates of the frequency of airway malacia in the general population are limited, its frequency in children with achondroplasia appears to be much higher than any published general population estimate. The presence of airway malacia appears to confound other breathing abnormalities in this population and results in the need for more invasive airway treatments.

Respiratory difficulties and breathing disorders in achondroplasia

Respiratory difficulties and breathing disorders in achondroplasia are thought to underlie the increased risk for sudden infant death and neuropsychological deficits seen in this condition. This review evaluates literature regarding respiratory dysfunctions and their sequelae in patients with achondroplasia. The limited number of prospective studies of respiratory disease in achondroplasia means that observational studies and case series provide a large proportion of the data regarding the spectrum of respiratory diseases in achondroplasia and their treatments. Amongst clinical respiratory problems described, snoring is the commonest observed abnormality, but the reported incidence of obstructive sleep apnoea (OSA) shows wide variance (10% to 75%). Reported treatments of OSA include adenotonsillectomy, the use of CPAP, and surgical improvement of the airway, including mid-face advancement. Otolaryngologic manifestations are also common. Respiratory failure due to small thoracic volumes is reported, but uncommon. Mortality rate at all ages was 2.27 (CI: 1.7-3.0) with age-specific mortality increased at all ages. Sudden death was most common in infants and children. Cardiovascular events are the main cause of mortality in adults. Despite earlier recognition and treatment of respiratory complications of achondroplasia, increased mortality rates and other complications remain high. Future and ongoing evaluation of the prevalence and impact of respiratory disorders, particularly OSA, in achondroplasia is recommended.

Managing snoring and obstructive sleep apnoea in childhood

Snoring assessment and its differentiation from obstructive sleep apnoea are difficult based upon a parent history and physical examination of the size of the tonsils. Not only is the presence of obstructive sleep apnoea important to diagnose, but confirming its severity is the key determinant in prioritising treatment in a resource-limited setting. This review provides current knowledge on the utility of common diagnostic tests, results of treatment options available and implications of treatment and unrecognised or untreated obstructive sleep apnoea.

Otolaryngologic manifestations of skeletal dysplasias in children

This article reviews some of the otolaryngologic manifestations of skeletal dysplasias. Achondroplasia is discussed most comprehensively. Skeletal dysplasias are bone and cartilage disorders that disrupt the development of the long bones, craniofacial skeleton, and vertebral column, with the most notable characteristic being short stature. Children with skeletal dysplasias have various medical problems. These children often develop head and neck manifestations of their disorders. Hearing loss, middle ear disease, and respiratory difficulties are seen in these children. Otolaryngologists must be knowledgeable about these disorders to diagnose, treat, and appropriately refer children with skeletal dysplasias.

Medical management of children with achondroplasia: evaluation of an Australasian cohort aged 0-5 years

AIMS

Achondroplasia is the most common form of osteochondrodysplasia and is associated with a number of life-threatening complications. The complexity of the condition led to the development of Heath Supervision Guidelines published by the American Academy of Pediatrics in 1995 and revised in 2005. There remains limited population-based information on utilisation of medical and therapy services for children with achondroplasia. Increased information regarding use of these services will assist in future service development.

METHODS

Data regarding frequency and timing of medical and allied health consultations, investigations and interventions were collected from 53 Australasian families via questionnaire, based on recommendations of the Health Supervision Guidelines, an expert reference group and literature review.

RESULTS

Rates varied with age for medical consultations (geneticist, paediatric rehabilitation physician/paediatrician, respiratory physician, orthopaedic consultant, neurologist, neurosurgeon), medical investigations (sleep study, magnetic resonance imaging/computed tomography), operative procedures (brain-stem decompression, tonsillectomy/adenoidectomy, shunt insertion, shunt revision and insertion of grommets) and allied health consultations (physiotherapist, occupational therapist, speech pathologist, dietician and orthotist).

CONCLUSIONS

Access to geneticists and paediatricians within the first year is high as recommended by the 2005 American Academy of Pediatrics guidelines. Utilisation of craniocervical magnetic resonance imaging/computed tomography, polysomnography studies and formal speech review appears low, reflecting more emphasis on clinical monitoring for cervical cord compression and disordered sleep breathing as well as possible difficulties in accessing services for polysomnography and speech pathology. Grommet insertion, tonsillectomy/adenoidectomy and cervicomedullary decompression rates are similar to results reported previously. Over half of the children accessed physiotherapy and/or occupational therapy services, warranting consideration of these professionals in future guideline recommendations.