Diaphragm and Lung Transplantation.

Mutual interactions between the diaphragm and lung transplantation (LTx) are known to exist. Before LTx, many factors can exert notable impact on the diaphragmatic function, such as the underlying respiratory disease, the comorbidities, and the chronic treatments of the patient. In the post-LTx setting, even the surgical procedure itself can cause a stressful trauma to the diaphragm, potentially leading to morphological and functional alterations. Conversely, the diaphragm can significantly influence various aspects of the LTx process, ranging from graft-to-chest cavity size matching to the long-term postoperative respiratory performance of the recipient. Despite this, there are still no standard criteria for evaluating, defining, and managing diaphragmatic dysfunction in the context of LTx to date. This deficiency hampers the accurate assessment of those factors which affect the diaphragm and its reciprocal influence on LTx outcomes. The objective of this narrative review is to delve into the complex role the diaphragm plays in the different stages of LTx and into the modifications of this muscle following surgery.

Balance and visual reliance in post-COVID syndrome patients assessed with a robotic system: a multi-sensory integration deficit.

The symptoms of SARS-CoV-2 infection are not limited to the acute phase, with vertigo, peripheral neuropathies, headache, fatigue, memory loss, and depression being the most common post-acute clinical manifestations. Such post-COVID syndrome is a new clinically relevant challenge for diagnosis and therapy. Our goal was to quantify deficit in balance and proprioception related to post-COVID syndrome and, in this sense, we prospectively analyzed data of 66 post-COVID-19 outpatients (mean age 47.3 ± 11.1 years, 50 females, 25 hospitalized), evaluated using the robotic device hunova. The dynamic balance was assessed with open (OE) and closed eyes (CE) and three indexes, proportional to subject instability, were measured: the sway path and two oscillation ranges. Hospitalized group showed the worst performance with respect to non-hospitalized patients and normality range in both visual conditions for the sway path and the oscillation ranges, with the worst performance being with CE. When compared to normality ranges, post-COVID patients were significantly more distant from normality in the OE condition compared to the CE condition. These results suggest that independently from the severity of the disease experienced, post-COVID syndrome makes the elastic balance test performances more distant from the normality when the subject integrates vision, somatosensory information, and vestibular information. In the absence of visual feedback, patients seem to implement compensatory strategies, presumably seeking more significant feedback from the lower limbs, which improve their performance. These data suggest a new mechanism of the post-COVID syndrome that deserves further investigation for its potential impact on activities of daily living.

Diaphragm Involvement in Duchenne Muscular Dystrophy (DMD): An MRI Study.

BACKGROUND: Duchenne muscular dystrophy (DMD) is characterized by progressive weakness and wasting of skeletal, cardiac, and respiratory muscles, with consequent cardiopulmonary failure as the main cause of death. Reliable outcome measures able to demonstrate specific trends over disease progression are essential. PURPOSE: To investigate MRI as a noninvasive imaging modality to assess diaphragm impairment in DMD. In particular, we sought to correlate MRI measurement of diaphragm structure and function with pulmonary function tests and with the abdominal volumes (VAB ) measured by optoelectronic plethysmography, being an index of the action of the diaphragm. STUDY TYPE: Cross-sectional study. POPULATION: Twenty-six DMD patients (17.9 ± 6.2 years) and 12 age-matched controls (17.8 ± 5.9 years). FIELD STRENGTH/SEQUENCE: 3-Point gradient echo Dixon sequence at 3T. ASSESSMENT: Images were acquired in breath-hold at full-expiration (EXP) and full-inspiration (INSP). INSP and EXP lung volumes were segmented and the diaphragm surface was reconstructed as the bottom surface of the left and the right lung. The inspiratory and the expiratory diaphragm surfaces were aligned by a nonrigid iterative closest point algorithm. On MRI we measured: 1) craniocaudal diaphragmatic excursion; 2) diaphragm fatty infiltration. STATISTICAL TESTS: Three-parameter sigmoid regression, one-way analysis of variance (ANOVA), Spearman's correlation. RESULTS: In patients, diaphragm excursion decreased with age (r2 = 0.68, P < 0.0001) and fat fraction increased (r2 = 0.51, P = 0.0002). In healthy subjects, diaphragm excursion and fat fraction had no relationship with age. Diaphragm excursion decreased with decreasing FEV1 %pred (r = 0.78, P < 0.0001) and FVC %pred (r = 0.76, P < 0.0001) and correlated with VAB (r = 0.60, P = 0.0002). Fatty infiltration increased with decreasing FEV1 %pred (r = -0.88, P < 0.0001) and FVC %pred (r = -0.88, P < 0.0001). DATA CONCLUSION: The progressive structural and functional diaphragm impairment is highly related to pulmonary function tests and to VAB . The results suggest that MRI might represent a new and noninvasive tool for the functional and structural assessment of the diaphragm. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2020;51:461-471.

Evolution of respiratory function in Duchenne muscular dystrophy from childhood to adulthood.

In Duchenne muscular dystrophy (DMD), it is still to be determined if specific timepoints can be identified during the natural evolution of respiratory dysfunction from childhood to adulthood and if scoliosis, steroid therapy and nocturnal noninvasive mechanical ventilation (NIMV) have any effect on it.In a 7-year retrospective study performed on 115 DMD patients (6-24 years), evaluated once or twice per year, with 574 visits in total, evolution mean curves of spirometry, lung volumes, spontaneous breathing and thoraco-abdominal pattern (measured by optoelectronic plethysmography) parameters were obtained by nonlinear regression model analysis.While predicted values of forced vital capacity, forced expiratory volume in 1 s, and peak expiratory flow decline continuously since childhood, during spontaneous breathing the following parameters become significantly different than normal in sequence: abdominal contribution to tidal volume (lower after 14.8 years), tidal volume (lower after 17.2 years), minute ventilation (lower after 18.1 years) and respiratory rate (higher after 22.1 years). Restrictive lung pattern and diaphragmatic impairment are exacerbated by scoliosis severity, slowed by steroids treatment and significantly affected by NIMV.Spirometry, lung volumes, breathing pattern and thoraco-abdominal contributions show different evolution curves over time. Specific timepoints of respiratory impairment are identified during disease progression. These should be considered when defining outcome measures in clinical trials and treatment strategies in DMD.

Respiratory muscle endurance training reduces the O2 cost of cycling and perceived exertion in obese adolescents.

In obesity, the increased O2 cost of breathing negatively affects the O2 cost of exercise and exercise tolerance. The purpose of the study was to determine whether, in obese adolescents, the addition of respiratory muscle endurance training (RMET) (isocapnic hyperpnea) to a standard body mass reduction program decreases the O2 cost of exercise and perceived exertion. Nine male obese adolescents [16.0 ± 1.4 yr (x ± SD), body mass 114.4 ± 22.3 kg] underwent 3 wk of RMET (5 days/week) in addition to a standard body mass reduction program. Eight age- and sex-matched obese adolescents underwent only the standard program (CTRL). Before and after interventions, patients performed on a cycle ergometer: incremental exercise; 12-min exercises at a constant work rate (CWR) of 65% and 120% at the gas exchange threshold (GET) determined before the intervention. Breath-by-breath pulmonary ventilation (V̇e) and O2 uptake (V̇o2), heart rate (HR), and ratings of perceived exertion for dyspnea/respiratory discomfort (RPER) and leg effort (RPEL) were determined. Body mass decreased (by ~3.0 kg) after both RMET (P = 0.003) and CTRL (P = 0.002). Peak V̇o2 was not affected by both interventions. Peak work rate was slightly, but significantly (P = 0.04), greater after RMET but not after CTRL. During CWR < GET, no changes were observed after both interventions. During CWR > GET, the O2 cost of cycling at the end of exercise (P = 0.02), the slope of V̇o2 vs. time (3-12 min) (P = 0.01), RPER (P = 0.01), and RPEL (P = 0.01) decreased following RMET, but not following CTRL. HR decreased after both RMET (P = 0.02) and CTRL (P = 0.03), whereas V̇e did not change. In obese adolescents RMET, superimposed on a standard body mass reduction program, lowered the O2 cost of cycling and perceived exertion during constant heavy-intensity exercise.

Sleep Disordered Breathing in Duchenne Muscular Dystrophy.

This review aims to explain the inevitable imbalance between respiratory load, drive, and muscular force that occurs in the natural aging of Duchenne muscular dystrophy and that predisposes these patients to sleep disordered breathing (SDB). In DMD, SDB is characterized by oxygen desaturation, apneas, hypercapnia, and hypoventilation during sleep and ultimately develops into respiratory failure during wakefulness. It can be present in all age groups. Young patients risk obstructive apneas because of weight gain, secondary to progressive physical inactivity and prolonged corticosteroid therapy; older patients hypoventilate and desaturate because of respiratory muscle weakness, in particular the diaphragm. These conditions are further exacerbated during REM sleep, the phase of maximal muscle hypotonia during which the diaphragm has to provide most of the ventilation. Evidence is given to the daytime predictors of early symptoms of SDB, important indicators for the proper time to initiate mechanical ventilation.

Influence of Tracheal Obstruction on the Efficacy of Superimposed High-frequency Jet Ventilation and Single-frequency Jet Ventilation.

BACKGROUND: Both superimposed high-frequency jet ventilation (SHFJV) and single-frequency (high-frequency) jet ventilation (HFJV) have been used with success for airway surgery, but SHFJV has been found to provide higher lung volumes and better gas exchange than HFJV in unobstructed airways. The authors systematically compared the ventilation efficacy of SHFJV and HFJV at different ventilation frequencies in a model of tracheal obstruction and describe the frequency and obstruction dependence of SHFJV efficacy. METHODS: Ten anesthetized animals (weight 25 to 31.5 kg) were alternately ventilated with SHFJV and HFJV at a set of different fHF from 50 to 600 min. Obstruction was created by insertion of interchangeable stents with ID 2 to 8 mm into the trachea. Chest wall volume was measured using optoelectronic plethysmography, airway pressures were recorded, and blood gases were analyzed repeatedly. RESULTS: SHFJV provided greater than 1.6 times higher end-expiratory chest wall volume than HFJV, and tidal volume (VT) was always greater than 200 ml with SHFJV. Increase of fHF from 50 to 600 min during HFJV resulted in a more than 30-fold VT decrease from 112 ml (97 to 130 ml) to negligible values and resulted in severe hypoxia and hypercapnia. During SHFJV, stent ID reduction from 8 to 2 mm increased end-expiratory chest wall volume by up to 3 times from approximately 100 to 300 ml and decreased VT by up to 4.2 times from approximately 470 to 110 ml. Oxygenation and ventilation were acceptable for 4 mm ID or more, but hypercapnia occurred with the 2 mm stent. CONCLUSION: In this in vivo porcine model of variable severe tracheal stenosis, SHFJV effectively increased lung volumes and maintained gas exchange and may be advantageous in severe airway obstruction.

20 years of neuromuscular electrical stimulation in COPD.

Although a lung disease, COPD is also associated with extrapulmonary manifestations including, among others, limb muscle dysfunction. Limb muscle dysfunction is a key systemic consequence of COPD that impacts patients' physical activity, exercise tolerance, quality of life and survival. Deconditioning is the main mechanism underlying the development of limb muscle dysfunction in COPD, which can be partially improved with exercise. However, some patients may not be able to tolerate exercise because of incapacitating breathlessness or unwillingness to undertake whole-body exercise. Alternative training modalities that do not give rise to dyspnoea, such as neuromuscular electrical stimulation (NMES), are urged. Over the past 20 years, NMES in COPD has presented conflicting conclusions in meta-analysis. In this review, we try to understand the reason for this result by analysing possible biases and factors that brought conflicting conclusions. We discuss the population (the intervention group, but also the control group), the outcome measures, the frequency of stimulation, the rehabilitation protocol (i.e. NMES alone versus standard care/rehabilitation or NMES plus conventional exercise training versus conventional exercise training alone or NMES versus sham treatment) and the trial design. The main reason for this discrepancy is the lack of dedicated guidelines for NMES. Further research is urged to determine the optimal parameters for an NMES programme. Despite this, NMES appears to be an effective means of enhancing quadriceps strength and exercise capacity in COPD with the potential to break the vicious circle induced by the disease and COPD patients' lifestyle.

Three-dimensional geometric morphometric shape analysis of chest wall kinematics in different breathing conditions.

Breathing motion is based on the differential activity of the thoracic, diaphragmatic and abdominal muscles. Muscle contributions differ between rest and exercise conditions and depend on posture and other factors. Traditionally, these changes are investigated on volumetric data using optoelectronic plethysmography (OEP). OEP offers insight into size variations of different chest wall (CW) compartments but does not provide three-dimensional visualization methods of CW breathing kinematics. Here we explore the use of three-dimensional geometric morphometrics to analyse size and shape changes caused by spontaneous breathing motion during quiet (QB), and recovery breathing (REC, immediately after heavy exercise) in two different postures (SIT, sitting on cycle ergometer; STA, standing position). Our findings show that size and shape differ significantly between inspiration and expiration and that differences are greater in REC than in QB. However, this is achieved by stronger expiration in SIT but by greater expiratory and inspiratory movements in STA. Shape analysis suggests that these differences may be attributed to constrained mobility of the shoulder girdle and a minor thoracic spine extension during inspiration owing to position on the ergometer. Breathing motion in STA seems biomechanically less constrained. Geometric morphometrics analyses can provide additional insights into data obtained by OEP.

Sarcopenia and Multisensory Integration Deficit in Post-COVID Syndrome Patients: The Clinical, Ultrasound and Robotic Evaluation Protocol in a Cross-sectional Study.

INTRODUCTION: Post-COVID syndrome affects relatively young outpatients with fatigue as the mostly reported symptom. We wondered whether sarcopenia could play a role. METHODS: Seventy-four outpatients (median age: 53.8 yrs, 45 females), reporting fatigue and persistent mild neurological/motor deficits, completed the Clinical, Ultrasound and Robotic Evaluation protocol 4.8 mos after the infection. RESULTS: The incidence of sarcopenia was 41%. Sarcopenic patients were older (62.7 vs. 46.4 yrs, P < 0.001), they experienced longer infection (33 vs. 24 days, P = 0.006) and higher incidence of hospitalization (86.6 vs. 29.5%, P < 0.001), they did not report more fatigue (44.5 vs. 48, P = 0.424), but they walked slower (1.27 vs. 1.5 m/sec, P = 0.027).After multivariable adjustment using multiple logistic regression, sarcopenia was dependent on age (odds ratio = 1.09) and on the duration of the disease (odds ratio = 1.04).When expressed as z score, in 79% of patients, the sway path during elastic balance shifted significantly toward negative values with closed eye, indicating multisensory integration deficit. CONCLUSIONS: Post-COVID syndrome in relatively young outpatients complaining mild motor deficit is associated with high incidence of sarcopenia. In addition, they have multisensory integration deficit that further contributes to symptoms. The Clinical, Ultrasound and Robotic Evaluation protocol is able to objectivize symptoms that common diagnostic tool cannot reveal. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME. CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) Determine the best diagnostic algorithm for the diagnosis of sarcopenia; (2) Identify and treat two additional factors that help to explain and understand the symptoms reported by relatively young post-COVID syndrome patients; and (3) Extend their diagnostic capability through the use of technology. LEVEL: Advanced. ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s) ™. Physicians should only claim credit commensurate with the extent of their participation in the activity. LEVEL: Advanced. ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s) ™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Limb Volume Measurements: A Comparison of Circumferential Techniques and Optoelectronic Systems against Water Displacement.

BACKGROUND: Accurate measurements of limb volumes are important for clinical reasons. We aimed to assess the reliability and validity of two centimetric and two optoelectronic techniques for limb volume measurements against water volumetry, defined as the gold standard. METHODS: Five different measurement methods were executed on the same day for each participant, namely water displacement, fixed-height (circumferences measured every 5 (10) cm for the upper (lower limb) centimetric technique, segmental centimetric technique (circumferences measured according to proportional height), optoelectronic plethysmography (OEP, based on a motion analysis system), and IGOODI Gate body scanner technology (which creates an accurate 3D avatar). RESULTS: A population of 22 (15 lower limbs, 11 upper limbs, 8 unilateral upper limb lymphoedema, and 6 unilateral lower limb lymphoedema) participants was selected. Compared to water displacement, the fixed-height centimetric method, the segmental centimetric method, the OEP, and the IGOODI technique resulted in mean errors of 1.2, 0.86, -16.0, and 0.71%, respectively. The corresponding slopes (and regression coefficients) of the linear regression lines were 1.0002 (0.98), 1.0047 (0.99), 0.874 (0.94) and 0.9966 (0.99). CONCLUSION: The centimetric methods and the IGOODI system are accurate in measuring limb volume with an error of <2%. It is important to evaluate new objective and reliable techniques to improve diagnostic and follow-up possibilities.

Spinal Postures and Mobility in Children with Achondroplasia vs. Age- and Sex-Matched Healthy Individuals: A Preliminary Report.

Background: Achondroplasia is a rare genetic disease, yet the most common form of dwarfism, characterized by limb shortening and disproportionate short stature along with musculoskeletal changes, such as postural deviations. Although postural changes in the spine in children with achondroplasia have been well investigated, little is known about the association of achondroplasia with spinal movements/mobility. Methods: This preliminary study aims to explore the association of achondroplasia with spinal mobility in children with achondroplasia compared to age- and sex-matched healthy individuals. Spinal posture and mobility were assessed using a radiation-free back scan, the Idiag M360 (Idiag, Fehraltorf, Switzerland). Between-group differences were determined using a two-way analysis of variance. Results: Children with achondroplasia had smaller thoracic lateral flexion [difference between groups (Δ) = 20.4°, 95% CI 0.1°-40.6°, p = 0.04], lumbar flexion (Δ = 17.4°, 95% CI 5.5°-29.4°, p = 0.006), lumbar extension (Δ = 14.2°, 95% CI 5.7°-22.8°, p = 0.002) and lumbar lateral flexion (Δ = 19.6°, 95% CI 10.7°-28.4°, p < 0.001) than age- and sex-matched healthy individuals, except for thoracic extension (Δ = 16.5°, 95% CI 4.4°-28.7°, p = 0.009) which was greater in children with achondroplasia. No differences were observed in global spinal postures between the two groups. Conclusions: Spinal mobility appears to be more influenced by achondroplasia than global spinal postures in childhood. These results also highlight the importance of considering the musculoskeletal assessment of segmental spinal postures and rehabilitative interventions aimed at promoting spinal flexibility in children with achondroplasia.

Urologic latency time during uroflow stop test with electromyography: an incontinence detector in rehabilitation after robotic radical prostatectomy.

BACKGROUND: Stress urinary incontinence (UI) is the most common presentation following robot-assisted radical prostatectomy (RARP), but a postoperative non-invasive and objective test is still lacking. To assess pelvic floor integrity after RARP, we recently proposed Uroflow Stop Test (UST) with surface electromyography (EMG). AIM: Here we provide two new clinical parameters: the neurologic latency time (NLT) and the urologic latency time (ULT) derived from UST-EMG Test. Principal outcome was to evaluate their variation during one year follow-up and ULT ability to predict post-RARP UI. DESIGN: Observational and longitudinal study. SETTING: Interdivisional Urology Clinic (Perugia-Terni, Italy). POPULATION: Patients with prostate cancer treated with a full nerve-sparing RARP who underwent postoperative pelvic floor muscles training (PFMT): a diurnal functional home program and a weekly hospital program with the use of biofeedback, between 1 and 3 months postoperatively. METHODS: All patients consecutively performed a UST-EMG test at one, three, six, and twelve months after surgery. At each follow-up visit we collected NLT values, ULT values, 5-item 26-Expanded Prostate Cancer Index (EPIC), Incontinence Developed on Incontinence Questionnaire (ICIQ-UI) Short Form and International Prostate Symptom Score (IPSS). We analysed statistically significant differences in NLT and ULT between continent and incontinent patients and we evaluate the diagnostic ability of 1-month post-surgery ULT value to diagnose the presence of postoperative UI. RESULTS: Sixty patients were enrolled. The mean time to PFMT was 31.08 (range: 30-35) days. Overall IPSS, NLT and ULT had similar trends: progressive decrease until the six months after surgery (1-month vs. 3 months vs. 6 months, P<0.05) to plateau thereafter. When considering the two group of patients, IPSS and NLT were significantly higher in the incontinent group only one month after surgery, while ULT became similar between the two groups at 6 months after surgery. The best cut-off of 1-month ULT values that maximized the Youden function at 12-months resulted 3.13 second. CONCLUSIONS: NLT and ULT may respectively account for the nerve and the urethral closure system integrity post-RARP. In the first month after RARP, both NLT and ULT differs between incontinent vs. continent patients. NLT become similar between two group after one month, confirming the recovery from neuropraxia, but ULT remains statistically significant different until 3 months postoperatively. The value of 1-month ULT resulted a valid tool to predict incontinence status at 12 months. CLINICAL REHABILITATION IMPACT: ULT and NLT may be also useful tools to monitor the continence progressive recovery after RARP and they may help rehabilitation specialists to evaluate the ongoing results during postoperative follow-up.

Key4OI Recommendations for Lung Function Guidance in Osteogenesis Imperfecta: Based on an Internationally Performed Comprehensive International Consortium for Health Outcomes Measurement Procedure.

INTRODUCTION: Pulmonary involvement in Osteogenesis Imperfecta (OI) can be severe but may be overlooked in milder cases. The Care4BrittleBones Foundation initiated this project to develop a set of global outcome measures focusing on respiratory-related issues in patients with OI. The objective was to reach an international consensus for a standardized set of outcomes and associated measuring instruments for the pulmonary care of individuals with OI. Based on the initial tests and questionnaires, we suggest parameters for when pulmonologists should seek guidance from the growing literature on OI pulmonary care and/or recognized experts in the field. STUDY DESIGN AND METHODS: The project team consisted of a multidisciplinary mix of 12 people from six countries, including an OI patient representative, and facilitated by the Care4BrittleBones Foundation director. The International Consortium for Health Outcomes Measurement (ICHOM) process was followed, which includes the Delphi method, used to collect the opinions of the expert team. Patient input was present in each meeting due to the inclusion of a patient representative. In addition, online focus groups were held. They consisted of adults with OI from different countries, and they determined which questions matter the most to the OI community worldwide. RESULTS: After three Delphi rounds, the expert team reached a consensus on the final set of measuring instruments, which included pulmonary function testing and patient self-reporting of symptoms related to breathing and sleep. Two questionnaires were decided upon: St. George's Respiratory Questionnaire (shortened version) and four questions regarding sleep. Patients should be screened for a history of pneumonia. Advanced testing for select patients by a pulmonologist would include further pulmonary function tests and a chest radiograph. CONCLUSIONS: A standardized set of outcome measures related to pulmonary care of individuals with OI was determined based on what is important to both experts and patients. This included patient-reported outcome measures and basic pulmonary function testing. Using these outcome measures, it can be determined which patients are at high risk for pulmonary complications.

Respiratory physiology in pregnancy and assessment of pulmonary function.

A progressive chest wall adaptation occurs during pregnancy driven by the hormones and the expanding uterus. The effect of the former is more prevalent in the first weeks of pregnancy, while the latter is more evident in the last trimester. The combination of the hormonal-induced joint loosening together with the progressively enlarging uterus produces changes in the whole chest wall geometry, with the thoracic alterations being the most fundamental. The ribcage changes in size, but not in volume, secondary to an upward bucket handle shift centred in the xiphoidal process so that the lung is not restricted. A virtuous cycle of stretching and muscle conditioning seems to be established between the enlarging uterus, the diaphragm, and the abdominal muscles to prepare these muscles for the expulsive phase. From the respiratory point of view, the supine position seems to hinder the action of the abdominal muscles during forced expiration at the end of pregnancy.

Lung and chest wall volume during vital capacity manoeuvre in Osteogenesis Imperfecta.

BACKGROUND: Although Osteogenesis Imperfecta (OI) affects the connective tissue, pulmonary function might be compromised because of thoracic deformities. OI is known to be a restrictive lung disease, but spirometry provides global measurement without localizing the site of the restriction. Opto-electronic plethysmography (OEP), is a non-invasive method able to underline altered respiratory function as well as ventilatory thoraco-abdominal paradoxes during spontaneous breathing. We aimed to reconstruct the thoraco-abdominal surface, to perform local analyses of trunk motion and to make quantitative comparison of trunk shape and respiratory kinematics according to OI severity, particularly during maximal inspiratory and expiratory expansions. This is a cross-sectional study where we have studied the thoraco-abdominal compartmental analysis in 26 adult OI patients (14 Type III) at rest and during vital capacity manoeuvre using OEP. We have also applied a new method that created realistic and accurate 3D models to perform local analyses of trunk motion and to make quantitative comparison of trunk shape and respiratory kinematics. RESULTS: Type III patients were characterized by lower spirometric lung volume, by lower sleep quality, by a more compressed thoracic configuration aggravated by severe scoliosis, by reduced global expansion at rest and during maximal maneuvers because of the reduced expansion of the pulmonary ribcage at rest (12% vs. 65% in healthy subjects), during maximal inspiration (37% vs. 69%) and expiration (16% vs. 68%) with local paradoxical movement occurring on the side of the ribcage region. CONCLUSION: The kinematics of the trunk changed to compensate for the severe structural deformities by shifting the expansion in the abdomen both at rest and during maximal manoeuvre because of a restricted thorax. For the first time, we have quantified and localized the site of the restriction in OI patients in the lateral part of the thorax. The 3D analysis proposed seemed a promising graphical immediate new method for pathophysiology study of chest wall restriction.