Rib Cage Deformity Research Articles

Are the Spinal Changes in the Course of Scoliogeny Primary but Secondary?

In this opinion article, there is an analysis and discussion regarding the effects of growth on the spinal and rib cage deformities, the role of the rib cage in scoliogeny, the lateral spinal profile in adolescent idiopathic scoliosis (AIS), the genetics and epigenetics of AIS, and the interesting and novel field investigating the sleep impact at nighttime on AIS in relation to the sequence of the scoliogenetic changes in scoliotics. The expressed opinions are mainly based on the published peer-reviewed research of the author and his team of co-authors. Based on the analysis noted above, it can be postulated that the vertebral growth changes in the spine during initial idiopathic scoliosis (IS) development are not primary-intrinsic but secondary changes. The primary cause starting the deformity is not located within the vertebral bodies. Instead, the deformations seen in the vertebral bodies are the secondary effects of asymmetrical loads exerted upon them, due to muscular loads, growth, and gravity.

Thoracic Cage Deformity Correction in Patients with Lenke Type 1 Adolescent Idiopathic Scoliosis.

Whether the thoracic cage deformity in adolescent idiopathic scoliosis (AIS) can be sufficiently treated with vertebral derotation alone, has been quite controversial. Our aim is to control the hypothesis that the rib cage deformity (RCD) may be adequately corrected when only vertebral derotation is applied. We studied retrospectively patients treated for AIS with posterior spinal fusion without costoplasty. The RCD was assessed on lateral radiographs by rib index (RI). The correction of RI after surgery was calculated. Of the 103 patients that were finally included in our study, 29 patients (22 females and 7 males; mean age, 14.5 ± 2.1 years) represented Group A (Harrington rod instrumentation - no derotation), while 74 patients (61 females and 13 males; mean age, 14.1 ± 2.4 years) were operated with either a full pedicle screw system or a hybrid construct with hooks and pedicle screws (Group B-derotation). RI was significantly corrected after surgery in both groups. RI was significantly greater in Group A after surgery. Whatsoever, the correction of RI, thereby the RCD correction, did not significantly differ among groups. In conclusion, it cannot be suggested by the present study that vertebral derotation alone can offer an absolute correction of the deformity of the thoracic cage in patients with Lenke Type 1 AIS, and it seems also that the development of RCD may not exclusively result from the spinal deformity, thus questions can be further raised regarding scoliogeny per se.

Extracorporeal shock wave lithotripsy, ureterolithotripsy, and percutaneous nephrolithotripsy challenges in managing spinal cord neuropathy patients. Lessons learned from a scoping review.

We aim to review the outcomes of shock wave lithotripsy (SWL), ureteroscopy, and percutaneous nephrolithotripsy (PCNL) for renal and ureteral stones in spinal cord neuropathy patients (SNP). A literature search was performed on 8th March 2023 using PubMed, EMBASE, and Google Scholar with no date limit. Preclinical/animal studies, reviews, letters to the editor, case reports, and meeting abstracts were excluded. Only English papers were accepted. Thirty-five articles were accepted. Five studies focused on SWL, 17 on PCNL, and 6 on ureteroscopy. The remaining articles employed more than one procedure. Stone composition has shifted from struvite to the more common calcium phosphate. SWL showed a very poor stone-free rate (SFR) likely due to challenges in patient positioning, stone visualization, localization, and inability to pass fragments spontaneously. Flexible ureteroscopy and PCNL were associated with a high incidence of infectious complications, long hospital stays, high blood transfusion rate, and intensive care admissions. There were also cases of death. Both procedures were challenging due to genitourinary reconstruction, scoliosis and kyphosis, rib-cage deformity, lower limb contractures, and severe comorbidity which also affected anesthesia. SFR was lower than in non-neurological patients. SWL, ureterolithotripsy, and PCNL should be considered challenging procedures in SNP due to positioning issues, an increased risk of intra and peri-operative morbidity, and even mortality. Computed tomography should be recommended to assess residual fragments as it becomes imperative to minimize a re-intervention in SNP who should be preferably treated in referral centers.

Segmental Rib Index and Spinal Deformity: Scoliogenic Implications.

The aim of this report is to evaluate the segmental rib index (RI) from the T1 to T12 spinal levels in mild and moderate idiopathic scoliosis (IS) curves of thoracic, thoracolumbar and lumbar type by gender. The relationship of segmental RI to the frontal plane radiological deformity presented as the Cobb angle and to the posterior truncal surface deformity presented as the scoliometric readings of Angle of Trunk Rotation (ATR) in these patients is also assessed. Any statistically significant relationship between these parameters would be very important for biomechanical relations in rib cage (RC) deformity presented as rib hump deformity (RHD) and deformity in the spine, and would thus provide valuable information about scoliogeny. The segmental rib index (RI) is presented in 83 boys and girls with mild and moderate IS. The measurements include the scoliometric readings for truncal asymmetry (TA), the Cobb angle assessment and the segmental RI from T1-T12. The statistical package SPSS 23 was used for statistical analysis. The TA was documented and the Cobb angle is presented by gender and curve type. The segmental RI of thoracic, thoracolumbar and lumbar curves are presented for the first time. The correlations of the segmental RI to surface deformity presented as rib hump deformity (RHD) in all IS patients, and particularly in thoracic curves, to Cobb angle by gender and age and the comparison of the segmental RI index of asymmetric but not scoliotic children to the scoliotic peers by curve (in thoracic, thoracolumbar, lumbar curves) in boys and girls are presented. The findings emphasize the significant protagonistic role of thoracic asymmetry in relation to the spinal deformity, mainly in girls for the thoracic and in boys for the thoracolumbar curves. The cut-off point of age of the examined scoliotics was 14 years, which is when the RI shows a stronger correlation with spinal deformity, namely when thoracic deformity is decisively effective in the development of thoracic spinal deformity, in terms of Cobb angle. In summary, the results of this study may provide scoliogenic implications for IS, as far as the role of the thorax is concerned.

Getting It Right in Restrictive Lung Disease.

Restrictive lung disease (predominantly in patients with neuromuscular disease (NMD) and ribcage deformity) may induce chronic hypercapnic respiratory failure, which represents an absolute indication to start home NIV (HNIV). However, in the early phases of NMD, patients may present only diurnal symptoms or orthopnoea and sleep disturbances with normal diurnal gas exchange. The evaluation of respiratory function decline may predict the presence of sleep disturbances (SD) and nocturnal hypoventilation that can be respectively diagnosed with polygraphy and PCO2 transcutaneous monitoring. If nocturnal hypoventilation and/or apnoea/hypopnea syndrome are detected, HNIV should be introduced. Once HNIV has been started, adequate follow-up is mandatory. The ventilator's built-in software provides important information about patient adherence and eventual leaks to correct. Detailed data about pressure and flow curves may suggest the presence of upper airway obstruction (UAO) during NIV that may occur with or without decrease in respiratory drive. Etiology and treatment of these two different forms of UAO are different. For this reason, in some circumstances, it might be useful to perform a polygraph. PtCO2 monitoring, together with pulse-oximetry, seem to be very important tools to optimize HNIV. The role of HNIV in neuromuscular disease is to correct diurnal and nocturnal hypoventilation with the consequence of improving quality of life, symptoms, and survival.

A Novel Method of Minimally Invasive Repair of Pectus Excavatum (MIRPE) in Patients with Bilateral Breast Prostheses: a Report of Two Patients

The literature on minimally invasive repair of pectus excavatum in patients with breast prostheses is very scarce, with only one report to date. We present two cases treated in our center in which this technique was performed without prior removal of the breast prostheses. In one of the patients, a sternal zenithal traction system was additionally used to facilitate retrosternal dissection. In this work, we present the technical details of the procedure. One of the patients presented with postoperative Dressler’s syndrome which resolved with conservative measures. We found no correlation between this complication and the presence of breast prostheses. After 4 and 2 years respectively, both patients are asymptomatic, with an adequate correction of the defect, and being followed up. Minimally invasive repair of pectus excavatum technique is safe and feasible in patients with bilateral breast prostheses. The placement of breast prostheses prior to the correction of rib cage deformities leads to an unpredictable aesthetic result in certain aspects, such as the exact positioning of the nipple areola complex. The approach to this pathology by a pediatric surgeon, who considers not only the aesthetic aspect but also the rib cage involvement and the potential presence of additional malformations (for example, a Poland sequence), is, in the authors’ opinion, beneficial to the overall outcome of these patients.

Constant score in asymptomatic shoulders varies with different demographic populations: derivation of adjusted score equation.

In the present study, the age- and sex-adjusted Constant score (CS) in a normal Indian population was calculated and any differences with other population cohorts assessed. The study participants were patients who visited the outpatient department for problems other than shoulder and healthy volunteers from the local population. Patients without shoulder pain/discomfort during activity were included in the study. Subjects with any problem that might affect shoulder function (e.g., cervical, thoracic spine, rib cage deformity, inflammatory arthritis) were excluded. Constant scoring of all participants was performed by trained senior residents under the supervision of the senior faculty. Shoulder range of movement and strength were measured following recommendations given by the research and Development Committee of the European Society for Shoulder and Elbow Surgery (2008). A fixed spring balance was used for strength measurement; one end was fixed on the floor and the other end tied with a strap to the wrist of the participant, arm in 90° abduction in scapular plane with palm facing down. Among the 248 subjects (496 shoulders), the average age was 37 years (range, 18-78 years), 65.7% were males (326 shoulders) and 34.3% females (170 shoulders). The mean CS was 84.6±2.9 (males, 86.1±3.0; females, 81.8±2.9). CS decreased significantly after 50 years of age in males and 40 years of age in females (p<0.05). The mean CS was lower than in previous studies for both males and females. Heavy occupation workers had higher mean CS (p<0.05). A linear standardized equation was estimated for calculating the adjusted CS for any age. Mean CS and its change with age differed from previous studies among various population cohorts.

Statistical changes of lung morphology in patients with adolescent idiopathic scoliosis after spinal fusion surgery-a prospective nonrandomized study based on low-dose biplanar X-ray imaging.

Adolescent idiopathic scoliosis (AIS) patients suffer from restrictive impairment of pulmonary function (PF) as a consequence of spinal and ribcage deformity. Statistic modelling of scoliotic geometry has been well-established based on low-dose biplanar X-ray device (EOS) imaging. However, the postoperative lung morphology change derived from EOS has not yet been studied adequately till now. Twenty-five female AIS patients with severe right-sided major thoracic curve (aged 13-31 years; Cobb angle 45°-92°) underwent posterior spinal fusion (PSF) were prospectively recruited for standing EOS imaging at preoperative, postoperative, and 1-year follow-up (1Y-FU) stages. EOS-based lung morphology at frontal and lateral view was measured respectively to assess serial statistical changes in area and height. At frontal view, left lung area significantly increased postoperatively (104.7 vs. 125.1 cm2; P<0.001) but without continuous increase at 1Y-FU (125.1 vs. 124.5 cm2; P=0.084), whereas right lung area showed a slight but insignificant interval increase (median: 143.8, 146.5, 148.4 cm2 at preoperative, postoperative, 1Y-FU stage, respectively; all P>0.05). At lateral view, the increase in left lung area was slight without statistically difference (median: 175.8, 178.4, 182.5 cm2 at preoperative, postoperative, 1Y-FU stage, respectively; all P>0.05), while right lung area did not significantly change postoperatively (median: 209.9, 206.7, 212.4 cm2 at preoperative, postoperative, 1Y-FU stage, respectively; all P>0.05). At both frontal and lateral view, left lung height significantly improved at both postoperative and 1Y-FU stage (all P<0.05), while preoperative right lung height was not significantly different from postoperative and 1Y-FU value (all P>0.05). EOS imaging demonstrates that left lung area in severe AIS may improve after PSF surgery. EOS may provide useful information about lung morphology change after PSF in severe AIS.

A Novel Classification of 3D Rib Cage Deformity in Subjects With Adolescent Idiopathic Scoliosis.

This was a multicentric cross-sectional descriptive study. To analyze patterns of 3D rib cage deformity in subjects with adolescent idiopathic scoliosis (AIS) and their relationship with the spinal deformity. Subjects with AIS present with rib cage deformity that can affect respiratory functions. The 3D rib cage deformities in AIS and their relationship to the spinal deformity are still unelucidated. A total of 200 AIS and 71 controls underwent low-dose biplanar x-rays and had their spine and rib cage reconstructed in 3-dimensional (D). Classic spinopelvic parameters were calculated in 3D and: rib cage gibbosity, thickness, width, volume and volumetric spinal penetration index (VSPI). Subjects with AIS were classified as: group I with mild rib cage deformity (n=88), group II with severe rib cage deformity (n=112) subgrouped into IIa (high gibbosity, n=48), IIb (high VSPI, n=48), and IIc (both high gibbosity and VSPI, n=16). Groups IIa and IIb had a higher Cobb angle (33 vs. 54 degrees and 46 degrees, respectively) and torsion index (11 vs. 14 degrees and 13 degrees, respectively) than group I. Group IIb showed more severe hypokyphosis (IIb=21 degrees; IIa=33 degrees; I=36 degrees; control=42 degrees) with a reduced rib cage volume (IIb=4731 cm3; IIa=4985 cm3; I=5257 cm3; control=5254 cm3) and thickness (IIb=135 mm; IIa=148 mm; I=144 mm; control=144 mm). Group IIa showed an increasingly large local gibbosity descending from proximal to distal levels and did not follow the axial rotation of the spine. Group IIc showed characteristics of both groups IIa and IIb. This new classification of 3D rib cage deformity in AIS shows that the management of cases with high VSPI (groups IIb and IIc) should focus on restoring as much kyphosis as possible to avoid respiratory repercussions. Treatment indications in groups I and IIa would follow the consensual basic principles reported in the literature regarding bracing and surgery.

A novel classification of 3D rib cage deformity in subjects with adolescent idiopathic scoliosis

Study design This was a multicentric cross-sectional descriptive study. Objective To analyze patterns of 3D rib cage deformity in subjects with adolescent idiopathic scoliosis (AIS) and their relationship with the spinal deformity. Summary of background data Subjects with AIS present with rib cage deformity that can affect respiratory functions. The 3D rib cage deformities in AIS and their relationship to the spinal deformity are still unelucidated. Methods A total of 200 AIS and 71 controls underwent low-dose biplanar x-rays and had their spine and rib cage reconstructed in 3-dimensional (D). Classic spinopelvic parameters were calculated in 3D and: rib cage gibbosity, thickness, width, volume and volumetric spinal penetration index (VSPI). Subjects with AIS were classified as: group I with mild rib cage deformity (n=88), group II with severe rib cage deformity (n=112) subgrouped into IIa (high gibbosity, n=48), IIb (high VSPI, n=48), and IIc (both high gibbosity and VSPI, n=16). Results Groups IIa and IIb had a higher Cobb angle (33 vs. 54 degrees and 46 degrees, respectively) and torsion index (11 vs. 14 degrees and 13 degrees, respectively) than group I. Group IIb showed more severe hypokyphosis (IIb=21 degrees; IIa=33 degrees; I=36 degrees; control=42 degrees) with a reduced rib cage volume (IIb=4731 cm3; IIa=4985 cm3; I=5257 cm3; control=5254 cm3) and thickness (IIb=135 mm; IIa=148 mm; I=144 mm; control=144 mm). Group IIa showed an increasingly large local gibbosity descending from proximal to distal levels and did not follow the axial rotation of the spine. Group IIc showed characteristics of both groups IIa and IIb. Conclusions This new classification of 3D rib cage deformity in AIS shows that the management of cases with high VSPI (groups IIb and IIc) should focus on restoring as much kyphosis as possible to avoid respiratory repercussions. Treatment indications in groups I and IIa would follow the consensual basic principles reported in the literature regarding bracing and surgery.

Rib Hump Deformity Correction in Patients with Adolescent Idiopathic Scoliosis: A Comparison of Three Spinal Fusion Systems.

The aim of the present study is to control the hypothesis that the rib hump deformity can be adequately corrected when applying vertebral derotation. We retrospectively studied patients treated with full pedicle screw systems (group A), hybrid constructs (group B), and Harrington rod instrumentation (group C). No costoplasties were performed in the patients included in our study. Derotation was applied in groups A and B. The rib hump deformity was assessed on lateral radiographic studies by rib index (RI). Of the 72 patients that were finally included in our study, 30 patients (24 females and 6 males; mean age, 14.5 ± 2.2 years) were treated with a full pedicle screw system, 23 patients (19 females and 4 males; mean age, 13.8 ± 1.9 years) were treated with a hybrid construct, and 19 patients (16 females and 3 males; mean age, 14.3 ± 2 years) received the Harrington rod instrumentation. In all groups RI was significantly corrected after surgery. Before surgery no difference in RI was found among groups; however, after surgery RI was found significantly higher in group C as compared to groups A and B. The between-group analysis revealed that the correction of RI, and thereby the rib hump deformity correction, did not significantly differ among the three patient groups. In conclusion, it cannot be suggested based on the present study that vertebral derotation alone can offer an adequate correction of the rib hump deformity. Further, the development of rib cage deformity and its degree of interdependence with the scoliotic spinal deformity has to be further investigated and assessed, as it seems that it may not necessarily result directly from the primary vertebral deformity.

Biomechanical Evaluation of Intercostal Muscles in Healthy Children and Adolescent Idiopathic Scoliosis: A Preliminary Study

Spine deformity during adolescent idiopathic scoliosis can induce a rib-cage deformity. This bone deformity can have direct consequences on the chest-wall muscles, including intercostal muscles, leading to respiratory impairments in individuals with severe cases. The aim of this study was to determine whether shear-wave elastography can be used to measure intercostal-muscle shear-wave speed (SWS) in healthy children and those with adolescent idiopathic scoliosis (AIS). Nineteen healthy participants and 16 with AIS took part. SWS measurements were taken by three operators, twice each. Average SWS was 2.3 ± 0.4 m/s, and inter-operator reproducibility was 0.2 m/s. SWS was significantly higher during apnea than in normal breathing (p < 0.01) in both groups. No significant difference was observed between groups in apnea or in normal breathing. Characterization of the intercostal muscles by ultrasound elastography is therefore feasible and reliable for children and adolescents with and without scoliosis.

Three-Dimensional Analysis of Preoperative and Postoperative Rib Cage Parameters by Simultaneous Biplanar Radiographic Scanning Technique in Adolescent Idiopathic Scoliosis: Minimum 2-Year Follow-Up.

Prospective study. This study aimed to investigate the changes in rib cage deformity in adolescent idiopathic scoliosis (AIS) by comparing the preoperative and postoperative three-dimensional (3D) reconstruction images using simultaneous biplanar radiographic scanning technique (EOS) (EOS Imaging, Paris, France). EOS data are limited for the analyses of preoperative and postoperative rib cage deformity. A total of 67 Lenke type 1 or 2 AIS patients who underwent surgery (59 females and 8 males) were enrolled in this study. The mean patient age was 14.4 years (range: 11-17 yr). In all patients, posterior corrective fusion was performed with a rod rotation maneuver based on segmental pedicle fixation. Spinal parameters (scoliosis and kyphosis) and rib cage parameters (max thickness, thoracic index (TI), rib hump (RH), surface spinal penetration index (sSPI), end thoracic hump ratio, vertebra-sternum angle, rib vertebral angle difference at the apex, and vertebral lateral decentering), were measured. 3D images were assessed preoperatively and postoperatively at 2-year follow-up. Both main thoracic (MT) and proximal thoracic scoliosis were significantly corrected (51° to 15°, 30° to 17°, P < 0.0001). The rotation of MT apical vertebrae was also significantly corrected (12° to 5°, P < 0.0001). Thoracic kyphosis (T4-T12) significantly increased (13° to 18°, P < 0.0001). Besides, max thickness, TI, and RH demonstrated significant differences between preoperative and postoperative images (P < 0.01). T8-10 sSPI and end thoracic hump ratio decreased significantly postoperatively (P < 0.05). Although surgery significantly decreased vertebra-sternum angle (P < 0.0001), no significant difference was observed between the preoperative and postoperative rib vertebral angle difference (P = 0.32). Following the surgery, vertebral lateral decentering and rib cage volume were significantly increased (P < 0.0001). 3D reconstruction of the rib cage using biplanar standing stereoradiography is useful to evaluate preoperative and postoperative rib cage deformity in patients with AIS.Level of Evidence: 2.

Thoracic mobility and its relation to pulmonary function and rib-cage deformity in patients with early onset idiopathic scoliosis: a long-term follow-up

Study designA group of adult patients with idiopathic scoliosis, diagnosed before the age of ten, at a mean of 26.5 years after treatment with either brace or surgery during childhood and adolescence attended a clinical follow-up.ObjectivesTo evaluate the relation between thoracic mobility, rib-cage deformity, and pulmonary function.Summary of background dataLong-term studies of pulmonary function in relation to thoracic mobility after treatment in this patient group have not been published.MethodsA total of 106 patients, 57 braced and 49 operated patients, attended the follow-up. We examined thoracic mobility (range of motion of the thoracic spine, thorax expansion, and breathing movements) and rib-cage deformity (curve size and trunk deformity) as well as pulmonary function, especially total lung capacity (TLC). Respiratory muscle strength was evaluated in a subgroup.ResultsThoracic range of motion was significantly less among the surgically treated patients compared with both the brace-treated and comparison group. Thorax expansion and breathing movements during maximal breathing were significantly reduced in the scoliotic patients compared with the reference values, with no significant differences between the treatment groups. The brace-treated group had better pulmonary function than the operated group, as measured by the TLC, forced vital capacity (FVC), and forced expiratory volume in one second (FEV1) (percentage of predicted values). The respiratory muscle strength was significantly lower only in the surgically treated patients when compared with reference values. The results of a multivariate analysis revealed that the strongest factors explaining TLC percentage of predicted were gender, brace model, and smoking habits.ConclusionsThoracic mobility was significantly reduced at mean 26.5 years after completed treatment in both brace-treated and surgically treated patients with early onset scoliosis, compared with the reference values, which did not influence TLC as strongly as gender, brace model, and smoking habits.Levels of evidenceLevel III.

Reliability measure of the rib cage deformity by a postural assessment software in patients with adolescent idiopathic scoliosis

Abstract Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine that generates changes in the biomechanics of the rib cage. Digital photogrammetry enables the recording of subtle changes and the interrelationship between parts of the human body that are difficult to measure by other means. The aim of this study was to create angles and thoracic distances and to evaluate the interobserver and intraobserver reliability of these measurements using the Software de Avaliação Postural (SAPO) in patients with AIS. This cross-sectional study evaluated 30 individuals aged between 11 and 18 years with AIS. We used SAPO with the thoracic markers in the form of angles (A) and distances (D) with involves structures like acromion, manubrium, xiphoid process, lower angle of the scapula, last false rib, anterior iliac spine process. Two experienced observers (A and B) analyzed the photos and all followed the same routine of analysis. Intraobserver and interobserver reproducibility was assessed by the Bland-Altman plot and intraclass correlation coefficient (ICC), while intraobserver and interobserver reliability was assessed by the T-Test and Wilcoxon's Test. A high repeatability index was obtained among the evaluations, with twelve of the sixteen variables considered as reliable in all statistical tests. The interobserver analyzes presented excellent correlation coefficients (ICC), showing good reliability for six of the sixteen variables proposed. The SAPO method presented good reproducibility and reliability for most of the thoracic markers created, showing that photogrammetry may be a complementary tool in the evaluation of thoracic alterations in patients with AIS.

Preoperative Evaluation of Pediatric Patients with Muscle Disorders

The preoperative assessment of pediatric patients with myopathy begins with a description of which muscle groups are impacted and the degree of disability present. Particular focus on respiratory status is necessary, as weak muscles of respiration can cause ventilatory insufficiency. This is exacerbated by swallowing difficulty, poor clearance of secretions, inadequate cough, and spinal and rib cage deformity. Restrictive lung disease may be severe. Cardiac dysfunction often accompanies skeletal muscle disease. Cardiomyopathy and conduction defects are prevalent in patients with muscle disorders and require preoperative evaluation. There is wide phenotypic variability among patients with muscle disease. By grouping myopathies according to pathophysiology, we can understand both the presentation and the most significant comorbidities associated with specific types of muscle disease. Finally, we can consider the specific anesthesia considerations that are pertinent to each, highlighting the risks of malignant hyperthermia and anesthesia-induced rhabdomyolysis. This review contains 3 tables and 38 references. Keywords: anesthesia considerations, congenital myopathy, malignant hyperthermia, mitochondrial disorders, muscular dystrophy, myotonia, succinylcholine, anesthesia-induced rhabdomyolysis

Combining Bilateral Magnetically Controlled Implants Inserted Parallel to the Spine With Rib to Pelvis Fixation: Surgical Technique and Early Results.

Spine-based fixation of magnetically controlled lengthening devices has been successfully performed for children with early-onset scoliosis. However, spinal manipulation may lead to ossifications, stiffness, and autofusion as previously described. To avoid these problems, a surgical technique combining bilateral externally controlled magnetic device implantation with a rib cradle and pelvic hook fixation was introduced by us in 2011. By using a bilateral single-rib or double-rib cradle fixation and a pelvic hook, the magnetic device is percutaneously inserted. The spine corrects indirectly without further manipulation. In small rib diameter or severe osteoporosis, double-rib cradles are used. Our introduced technique enables modification of the rib vertebral angle, which may be beneficial in children with spinal muscular atrophy and rib-cage deformity. This nonrandomized prospective study describes 18 children with neuromuscular scoliosis treated first by this method. All patients followed the same protocol, with expansion procedures being performed 5 months after surgery and every 3 months thereafter. Clinical, radiologic, and complication data were analyzed, showing a significant reduction in scoliosis and pelvic obliquity and an increase in spinal length, which could be maintained over a follow-up period of 1.2 years. The overall complication rate was lower than previously described, with 8%, 2 of them requiring surgery.

Ribcage deformity and the altered breathing pattern in children with osteogenesis imperfecta.

Osteogenesis Imperfecta (OI) is a genetic disease characterized by bones fragility and progressive deformity. Life expectancy is reduced in the non-lethal most severe type III form before the age of 10 years. The main cause of death in OI is respiratory insufficiency resulting from impaired thoracic function worsened by ribcage deformity and scoliosis. We used opto-electronic plethysmography to study chest geometry, the ventilatory, and the thoraco-abdominal pattern at rest in supine position in children younger than 10 years. Radiographic measurements were used to describe spinal deformity. Eight severe OI (sOI), seven affected by other moderate forms (mOI), and nine healthy controls (CTR) were analyzed. sOI were characterized by Pectus carinatum (sternal angle: 165.2°, CTR: 183.1°; P < 0.01), rapid and shallow breathing (RSBi: 267.4 L-1 min-1 , CTR: 150.7 L-1 min-1 ; P < 0.05) and reduced pulmonary rib cage contribution to tidal volume (5.1%, CTR: 14.6%; P < 0.001) that evolved with age approaching the paradoxical inspiratory inward movement previously found in adults. mOI showed almost normal ventilatory pattern (RSBi: 189.2-1 min-1 ) and absence of sternal deformity (sternal angle: 176.8°). Platyspondyly and kyphosis were common features in all OI children. An altered breathing pattern in severe OI is present since childhood and it worsens with age. This is caused by the combination of pectus carinatum, brittle ribs and spinal deformity that put the ribcage muscles in mechanical disadvantage. These results suggest that in severe OI the assessment of the respiratory function should start in early childhood in order to try to reduce the incidence of premature death.

Pulmonary and diaphragmatic pathology in collagen type I α1 mutant mice with osteogenesis imperfecta.

BackgroundOsteogenesis imperfecta (OI) is most often caused by mutations in type I collagen genes. Respiratory complications have been largely attributed to spine and ribcage deformities. We hypothesized that direct involvement of the pulmonary parenchyma and/or diaphragm by the disease may occur.MethodsIn Col1a1Jrt/+ mice, a model of severe dominant OI, mean linear intercept length (Lm) was used to assess the distal airspace size. Cross-sectional area (CSA) and myosin heavy chain (MyHC) phenotype of the diaphragm muscle fibers, as well as contractile properties, were determined. OI mice were also treated with neutralizing antibodies against transforming growth factor-β (TGF-β).ResultsDistal airspace enlargement occurred in OI mice (Lm +27%). Diaphragmatic thickness and fiber number were reduced, with increases in fast-twitch type IIx/IIb MyHC fibers. Ex vivo force generation (normalized for CSA) of the diaphragm was also significantly reduced. The increased Lm values found in OI mice were not prevented by anti-TGF-β antibody treatment.ConclusionsThe Col1a1Jrt/+ mouse model of OI demonstrates: (1) pulmonary airspace enlargement not driven by TGF-β; and (2) reduced muscle mass and intrinsic contractile weakness of the diaphragm. These results suggest a complex and multifaceted basis for respiratory complications in OI that cannot be solely attributed to bone manifestations.

Stage specific requirement of platelet-derived growth factor receptor-α in embryonic development.

BackgroundPlatelet-derived growth factor receptor alpha (PDGFRα) is a cell-surface receptor tyrosine kinase for platelet-derived growth factors. Correct timing and level of Pdgfra expression is crucial for embryo development, and deletion of Pdgfra caused developmental defects of multiple endoderm and mesoderm derived structures, resulting in a complex phenotypes including orofacial cleft, spina bifida, rib deformities, and omphalocele in mice. However, it is not clear if deletion of Pdgfra at different embryonic stages differentially affects these structures.PurposeTo address the temporal requirement of Pdgfra in embryonic development.MethodsWe have deleted the Pdgfra in Pdgfra-expressing tissues at different embryonic stages in mice, examined and quantified the developmental anomalies.ResultsCurrent study showed that (i) conditional deletion of Pdgfra at different embryonic days (between E7.5 and E10.5) resulted in orofacial cleft, spina bifida, rib cage deformities, and omphalocele, and (ii) the day of Pdgfra deletion influenced the combinations, incidence and severities of these anomalies. Deletion of Pdgfra caused apoptosis of Pdgfra-expressing tissues, and developmental defects of their derivatives.ConclusionOrofacial cleft, spina bifida and omphalocele are among the commonest skeletal and abdominal wall defects of newborns, but their genetic etiologies are largely unknown. The remarkable resemblance of our conditional Pdgfra knockout embryos to theses human congenital anomalies, suggesting that dysregulated PDGFRA expression could cause these anomalies in human. Future work should aim at defining (a) the regulatory elements for the expression of the human PDGFRA during embryonic development, and (b) if mutations / sequence variations of these regulatory elements cause these anomalies.