Trans-vocalic coronal consonant coarticulation in Central Arrernte: An electro-palatographic study

This study examines trans-vocalic CVC coarticulation of the coronal (dental, alveolar, retroflex and (alveo-)palatal) stop, nasal and lateral consonants of Arrernte, an Aboriginal language of Central Australia, using electro-palatographic (EPG) recordings of continuous speech. Coronal consonants are known to be more coarticulatorily resistant than peripheral consonants such as bilabials and velars, and this study teases out the coarticulatory differences between these four coronal places of articulation. Results confirm findings from previous studies that laminal consonants (dental and alveo-palatal) are broadly more coarticulatorily aggressive than apical consonants (alveolars and retroflexes), with the alveolars the least resistant to coarticulation. Dental consonants exert fronting effects on both preceding and following consonants, a result consistent with previous acoustic results for these sounds. Similarly, alveo-palatal consonants show both anticipatory and carryover effects, though their exact coarticulatory effect depends on the affected consonant place and manner. The retroflex consonants exert strong fronting effects on the following consonant, and it is suggested that this is due to the anterior release of retroflexes following ballistic forward movement during closure. There is also some evidence of a retraction effect of retroflexes on preceding consonants. Despite this evidence of coarticulatory aggression, retroflexes are particularly affected by preceding and following palatals: in these cases, the retroflex articulation becomes more forward, and dorsal contact for the retroflex is increased. In sum, by examining speech in an understudied language, we learn that there are still greater complexities in the co-ordination of consonants produced using the tongue tip and blade.

A novel posterior multiple screws distraction reducer system versus anterior release, posterior internal distraction, and subsequent spinal fusion for severe scoliosis

Purpose We previously reported anterior release, posterior internal distraction, and subsequent spinal fusion (ARPIDF) for the correction of severe scoliosis with a satisfactory correction rate. However, surgical procedures were completed in 2–3 stages. Here we compare Cobb angle of ≥90° in scoliosis correction between a novel posterior multiple screws distraction reducer (MSDR) system and ARPIDF. Methods Thirty-six patients with severe scoliosis treated by MSDR or ARPIDF (n = 18 in both groups). We retrospectively analyzed and compared outcome measures between the two groups over a minimum follow-up duration of 2 years. The following variables were compared between the two groups: age at surgery, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, operation time, estimated blood loss, hospitalization time, follow-up duration, various radiological parameters, complication rate, and Scoliosis Research Society-30 score. Results There were no significant between-group differences with respect to age, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, and follow-up duration. Further, there was no significant difference in terms of preoperative, postoperative, and final follow-up findings of the radiographic data. However, the ARPIDF group had longer operation and hospitalization times and greater blood loss. In the ARPIDF group, 4 patient developed complications (infection, intraoperative neuromonitoring changes, transient dyspnea); none of these events occurred in the MSDR group. Conclusion The use of MSDR helped achieve greater scoliosis correction with a shorter operation time, lower blood loss, and lower complication rate than the use of ARPIDF. MSDR facilitates safer and easier correction of severe scoliosis without increasing surgical risk.

Management of pediatric patients with irreducible atlantoaxial dislocation: transoral anterior release, reduction, and fixation

OBJECTIVEAlthough transoral atlantoaxial reduction plate (TARP) surgery has been confirmed to be safe and effective for adults who have irreducible atlantoaxial dislocation (IAAD) with or without basilar invagination or upper cervical revision surgery, it is rarely used to treat these disorders in children. The authors of this study aimed to report on the use of the anterior technique in treating pediatric IAAD.METHODSIn this retrospective study, the authors identified 8 consecutive patients with IAAD who had undergone surgical reduction at a single institution in the period between January 2011 and June 2104. The patients consisted of 5 males and 3 females. Three had os odontoideum, 2 had basilar invagination, and the other 3 experienced atlantoaxial rotatory fixed dislocation (AARFD). They were all treated using transoral anterior release, reduction, and fusion with the TARP. Preoperative and postoperative CT scans and MR images were obtained. American Spinal Injury Association (ASIA) Impairment Scale grades were determined.RESULTSAll symptoms were relieved in all 8 patients but to varying degrees. Intraoperative loose reduction and fixation of C1–2 were achieved in one stage. The 4 patients with preoperative neurological deficits were significantly improved after surgery, and their latest follow-ups indicated that their ASIA Impairment Scale grades had improved to E. Postoperative pneumonia occurred in 1 patient but was under complete control after anti-infective therapy and fiber optic–guided sputum suction.CONCLUSIONSOne-stage transoral anterior release, reduction, and fixation is an effective, reliable, and safe means of treating pediatric IAAD. The midterm clinical results are satisfactory, with the technique eliminating the need for interval traction and/or second-stage posterior instrumentation and fusion.

PREOPERATIVE HALO-GRAVITY TRACTION WITH AND WITHOUT ANTERIOR RELEASE FOR SEVERE SCOLIOSIS

ABSTRACT Objective: This study aims to compare the use of halo-gravity traction (HGT) with and without previous anterior release, in terms of curve reduction, for the treatment of pediatric severe spinal deformity. Methods: From 2010 to 2016, all patients treated with HGT prior to instrumentation for scoliosis and kyphoscoliosis were reviewed. They were assessed by deformity etiology, previous anterior release, instrumentation procedure used, traction protocol, major Cobb angle before traction, after the protocol, and after the instrumentation procedure. Twelve patients met these criteria and constituted the sample groups: Group I (n=7) with anterior release and Group II (n=5) without anterior release. Results: The average pre-traction major curve Cobb angles were 114.9o and 108.4º for Group I and II, respectively (P>0.05). After HGT, both groups achieved a significant reduction in curve angle (P<0.05). Group I presented an average Cobb angle of 95.0o after HGT, representing a 17.3% (19.8o) curve reduction. Group II presented a Cobb angle of 80.1o, representing a 25.2% (28.4o) curve reduction. The difference between the two groups in relation to the reduction of major curve after HGT was not statistically significant (P=0.073). After the surgical procedure, the correction achieved was significantly improved (P<0.05), without statistically significant difference between the two groups (P>0.05). No major HGT related complications were reported. Conclusions: Anterior release prior to HGT did not increase major curve correction after posterior surgery for severe pediatric idiopathic and syndromic scoliosis. HGT is an effective and safe technique, though it frequently presents minor and transitory complications. Level of Evidence III; Retrospective Comparative Study.