How Can Biomechanical Multibody Models of Scoliosis Be Accurate in Simulating Spine Movement Behavior While Neglecting the Changes of Spinal Length?

This paper studies how biomechanical multibody models of scoliosis can neglect the changes of spinal length and yet be accurate in reconstructing spinal columns. As these models with fixed length comprise rigid links interconnected by rotary joints, they resemble polygonal chains that approximate spine curves with a finite number of line segments. In mathematics, using more segments with shorter length can result in more accurate curve approximations. This raises the question of whether more accurate spine curve approximations by increasing the number of links/joints can yield more accurate spinal column reconstructions. For this, the accuracy of spine curve approximation was improved consistently by increasing the number of links/joints, and its effects on the accuracy of spinal column reconstruction were assessed. Positive correlation was found between the accuracy of spine reconstruction and curve approximation. It was shown that while increasing the accuracy of curve approximations, the representation of scoliosis concavity and its side-to-side deviations were improved. Moreover, reconstruction errors of the spine regions separated by the inflection vertebrae had minimal impacts on each other. Overall, multibody scoliosis models with fixed spinal length can benefit from the extra rotational joints that contribute towards the accuracy of spine curve approximation. The outcome of this study leads to concurrent accuracy improvement and simplification of multibody models; joint-link configurations can be independently defined for the regions separated by the inflection vertebrae, enabling local optimization of the models for higher accuracy without unnecessary added complexity to the whole model.

TRACHEAL INTUBATION DURING MANUAL INLINE STABILISATION: COMPARISON OF INTUBATING LARYNGEAL MASK AIRWAY™ VERSUS TRACHLIGHT®

Introduction: Airway management with unstable cervical spine is a major challenge to anesthetist. Conventional direct laryngoscopy causes substantial movement of cervical spine and can cause neurological decit. Newer devices like Intubating Laryngeal Mask Airway(ILMA) and Trachlight avoid cervical spine movement. To compare rate of successful tracheal Aim: intubation with Intubating Laryngeal Mask Airway™ with Trachlight® in anaesthetised and paralysed adults with manual in line stabilization Method and Materials: 50 patients were included in the study and allocated in two groups. In the ILMA group ,patients were ventilated and then intubated through the ILma. IN the Trachlight group, patients were intubated using trachlight. Success rate , time taken for intubation and post operative sore throat and hoarseness of voice were compared between the two groups. Results: In the ILMA group,21 patients could be adequately ventilated in the rst attempt and 4 in second attempt. 12 patients could be successfully intubated. 9 patients could be intubated in the rst attempt and 3 patients in second attempt. In the Trachlight , 24 patients could be intubated in the rst attempt and one patient in second attempt. Intubation time was 14.08 ± 2.23 seconds in the ILMA group whereas in Trachlight group it was 26.48 ± 9.13 seconds(p value of <0.0001) In healthy anaesthetized,paralysed adults with manual in line stabiliz Conclusion: ation Trachlight assistance at tracheal intubation provides high rst attempt success.ILMA is an effective ventilation device, but an unacceptably high failure rate at blind tracheal intubation.

Fiberoptic, Video Laryngoscope, and Nasal Airway Procedures

In patients with known or suspected difficult airways, advanced airway procedures such as fiberoptic laryngoscopy (under general anesthesia—with and without supraglottic airways—and sometimes in awake patients) as well as video laryngoscopy are invaluable. All may be particularly advantageous for use with patients who have limited or reduced cervical spine movement. Other advantages and disadvantages are addressed in this chapter. Techniques for nasotracheal intubation are also described. Flexible fiberoptic laryngoscopy is a means of indirectly visualizing airway structures by threading a fiberoptic scope with a camera at the end of the scope into the airway. The goal of fiberoptic laryngoscopy is endotracheal intubation using a Seldinger technique, whereby an endotracheal tube is guided into the trachea over the fiberoptic bronchoscope. Fiberoptic endotracheal intubation may be performed through the mouth or nose, or through a supraglottic airway (SGA). The use of the fiberoptic scope through an SGA is an especially useful technique in infants who suffer from airway obstruction at rest (e.g., infants with Pierre Robin syndrome). Video laryngoscopy employs a laryngoscope with a camera at the end of the blade to enable the user to indirectly visualize airway structures.

An Unexplained Case of Progressive Spastic Paraparesis in an Individual with Known DiGeorge Syndrome

DiGeorge syndrome (22q11.2 deletion) is associated with several neurologic disorders including structural abnormalities involving brain and spine, movement disorders, and epilepsy. Progressive spastic paraparesis has not been reported with DiGeorge syndrome. We report an individual in which DiGeorge syndrome was associated with progressive spastic paraparesis. This report extends the clinical phenotype of DiGeorge syndrome and presents the differential diagnosis of progressive spastic paraparesis in individuals with DiGeorge syndrome which provides insight into the clinical evaluation of such individuals.

Remaining Cervical Spine Movement Under Different Immobilization Techniques

Background:Immobilization of the cervical spine by Emergency Medical Services (EMS) personnel is a standard procedure. In most EMS, multiple immobilization tools are available.The aim of this study is the analysis of residual spine motion under different types of cervical spine immobilization.Methods:In this explorative biomechanical study, different immobilization techniques were performed on three healthy subjects. The test subjects’ heads were then passively moved to cause standardized spinal motion. The primary endpoints were the remaining range of motion for flexion, extension, bending, and rotation measured with a wireless human motion detector.Results:In the case of immobilization of the test person (TP) on a straight (0°) vacuum mattress, the remaining rotation of the cervical spine could be reduced from 7° to 3° by additional headblocks. Also, the remaining flexion and extension were reduced from 14° to 3° and from 15° to 6°, respectively. The subjects’ immobilization was best on a spine board using a headlock system and the Spider Strap belt system (MIH-Medical; Georgsmarienhütte, Germany). However, the remaining cervical spine extension increased from 1° to 9° if a Speedclip belt system was used (Laerdal; Stavanger, Norway). The additional use of a cervical collar was not advantageous in reducing cervical spine movement with a spine board or vacuum mattress.Conclusions:The remaining movement of the cervical spine is minimal when the patient is immobilized on a spine board with a headlock system and a Spider Strap harness system or on a vacuum mattress with additional headblocks. The remaining movement of the cervical spine could not be reduced by the additional use of a cervical collar.

Video Laryngoscopic Intubation Using the King VisionTM Laryngoscope in a Simulated Cervical Spine Trauma: A Comparison Between Non-Channeled and Channeled Disposable Blades

Videolaryngoscopes may reduce cervical spine movement during tracheal intubation in patients with neck trauma. This manikin study aimed to compare the performance of disposable non-channeled and channeled blades of the King Vision™ videolaryngoscope in simulated cervical spine injury. Fifty-eight anesthesiologists in training intubated the TruMan manikin with the neck immobilized using each blade in a randomized order. The primary outcome was the time needed for tracheal intubation, secondary aims included total success rate, the time required for visualization of the larynx, number of attempts, view of the vocal cords, and subjective assessment of both methods. Intubation time with the channeled blade was shorter, with a median time of 13 s (IQR 9–19) vs. 23 s (14.5–37.5), p < 0.001, while times to visualization of the larynx were similar in both groups (p = 0.54). Success rates were similar in both groups, but intubation with the non-channeled blade required more attempts (1.52 vs. 1.05; p < 0.001). The participants scored the intubation features of the channeled blade significantly higher, while visualization features were scored similarly in both groups. Both blades of the King Vision™ videolaryngoscope are reliable intubation devices in a simulated cervical spine injury in a manikin model when inserted by non-experienced operators. The channeled blade allowed faster intubation of the trachea.

Dynamical determinants of different spine movements and gait speeds in rotary and transverse gallops

Quadruped gallop is categorized into two types: rotary and transverse. While the rotary gallop involves two types of flight with different spine movements, the transverse gallop involves only one type of flight. The rotary gallop can achieve faster locomotion than the transverse gallop. To clarify these mechanisms from a dynamic viewpoint, we developed a simple model and derived periodic solutions by focusing on cheetahs and horses. The solutions gave a criterion to determine the flight type: while the ground reaction force does not change the direction of the spine movement for the rotary gallop, it changes for the transverse gallop, which was verified with the help of animal data. Furthermore, the criterion provided the mechanism by which the rotary gallop achieves higher-speed than the transverse gallop based on the flight duration. These findings improve our understanding of the mechanisms underlying different gaits that animals use.