Light actuated remote control security system

A remote control security apparatus includes a lock element movable between locked and unlocked positions by an electrically actuated power device. The operator is provided with a portable transmitter adapted to generate light which is interrupted at a predetermined frequency so as to produce an encoded light signal. This signal is detected by a light transceiver which generates an independent signal at the same predetermined frequency and which compares the frequencies of the detected signal and independent signal. If these frequencies are substantially the same, the transceiver actuates the power means to move the lock element to its unlocked position. The security apparatus may be advantageously installed as a door lock, in which case a lock element receiving member is secured to the door. The signal detector is positioned at the exterior side of the door for receiving encoded signals from the transmitter and an override switch may be positioned at an interior side of the door for opening the lock without a transmitter. A contact switch is disclosed which maintains the lock element in the unlocked position whenever the door is open

Journal of Cardiovascular Magnetic Resonance ® , 3(4), 349–360 (2001) Mechanisms of the Effects of Nicorandil in the Isolated Rat Heart During Ischemia and Reperfusion: A 31 P-Nuclear Magnetic Resonance Study

Nicorandil (SG75) is a potent K �-channel activator with an additional nitro moiety. In the present study we investigated the potential mechanisms (K �-channel activation and nitric oxide [NO] release) for the effects of nicorandil on isolated perfused rat hearts during total global ischemia using 31 P-nuclear magnetic resonance. After a 10-min control perfusion, hearts were subjected to treatment with nicorandilcontaining (100, 300, or 1000 µM) buffer for 10 min, 15 min of total global ischemia, and 30 min of reperfusion. At high dose (10 �3 M), nicorandil reduced ATP depletion during ischemia by 26 % compared with untreated hearts. Blockade of K � channels by glibenclamide prevented this protective effect. At all doses (10 �4 to 10 �3 M), nicorandil reduced the accumulation of protons during ischemia compared with untreated hearts (pH 6.22 � 0.03 vs. 6.02 � 0.05 in untreated hearts at the end of ischemia). This effect was preserved after blockade of K � channels by glibenclamide. Hearts treated with nitroglycerine before ischemia also showed reduced proton accumulation. Therefore, NO release accompanied by increased coronary flow before ischemia, which is caused by the nitro moiety of nicorandil and nitroglycerine treatment, results in reduced proton accumulation. During reperfusion, a pro-arrhythmic effect was observed in hearts treated with the nonpharmacologically high dose of nicorandil (1000 µM). Thus, we conclude that the effects of nicorandil are caused Address correspondence and reprint requests to Michael Horn

Does the Spine Surgeon’s Experience Affect Fracture Classification, Assessment of Stability, and Treatment Plan in Thoracolumbar Injuries?

Study Design: Prospective survey-based study. Objectives: The AO Spine thoracolumbar injury classification has been shown to have good reproducibility among clinicians. However, the influence of spine surgeons’ clinical experience on fracture classification, stability assessment, and decision on management based on this classification has not been studied. Furthermore, the usefulness of varying imaging modalities including radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) in the decision process was also studied. Methods: Forty-one spine surgeons from different regions, acquainted with the AOSpine classification system, were provided with 30 thoracolumbar fractures in a 3-step assessment: first radiographs, followed by CT and MRI. Surgeons classified the fracture, evaluated stability, chose management, and identified reasons for any changes. The surgeons were divided into 2 groups based on years of clinical experience as \u3c10 years (n = 12) and \u3e10 years (n = 29). Results: There were no significant differences between the 2 groups in correctly classifying A1, B2, and C type fractures. Surgeons with less experience hadmore correct diagnosis in classifyingA3 (47.2% vs 38.5%in step 1, 73.6% vs 60.3% in step 2 and 77.8% vs 65.5% in step 3), A4 (16.7% vs 24.1% in step 1, 72.9% vs 57.8% in step 2 and 70.8% vs 56.0%in step3) and B1 injuries (31.9% vs 20.7% in step 1, 41.7% vs 36.8% in step 2 and 38.9% vs 33.9% in step 3). In the assessment of fracture stability and decision on treatment, the less and more experienced surgeons performed equally. The selection of a particular treatment plan varied in all subtypes except in A1 and C type injuries. Conclusion: Surgeons’ experience did not significantly affect overall fracture classification, evaluating stability and planning the treatment. Surgeons with less experience had a higher percentage of correct classification in A3 and A4 injuries. Despite variations between them in classification, the assessment of overall stability and management decisions were similar between the 2 groups. © The Author(s) 2017

Open Posterior Reduction and Stabilization of AO Spine C3 Sacral Fractures.

AO Spine C3 sacral fractures are defined by separation of the spine including S1 from the pelvic ring and are usually result of a high-energy injury. Besides their high biomechanical instability and high rate of associated neurological impairment, these fractures are often extremely difficult to reduce due to severe bony impaction and dislocation. Additional difficulties in management of these fractures arise from only a thin-layer of soft-tissue coverage overlying the injured area

AOSpine—Spine Trauma Classification System: The Value of Modifiers: A Narrative Review With Commentary on Evolving Descriptive Principles

Study Design: Narrative review. Objectives: To describe the current AOSpine Trauma Classification system for spinal trauma and highlight the value of patient-specific modifiers for facilitating communication and nuances in treatment. Methods: The classification for spine trauma previously developed by The AOSpine Knowledge Forum is reviewed and the importance of case modifiers in this system is discussed. Results: A successful classification system facilitates communication and agreement between physicians while also determining injury severity and provides guidance on prognosis and treatment. As each injury may be unique among different patients, the importance of considering patient-specific characteristics is highlighted in this review. In the current AOSpine Trauma Classification, the spinal column is divided into 4 regions: the upper cervical spine (C0-C2), subaxial cervical spine (C3-C7), thoracolumbar spine (T1-L5), and the sacral spine (S1-S5, including coccyx). Each region is classified according to a hierarchical system with increasing levels of injury or instability and represents the morphology of the injury, neurologic status, and clinical modifiers. Specifically, these clinical modifiers are denoted starting with M followed by a number. They describe unique conditions that may change treatment approach such as the presence of significant soft tissue damage, uncertainty about posterior tension band injury, or the presence of a critical disc herniation in a cervical bilateral facet dislocation. These characteristics are described in detail for each spinal region. Conclusions: Patient-specific modifiers in the AOSpine Trauma Classification highlight unique clinical characteristics for each injury and facilitate communication and treatment between surgeons

Variation in global treatment for subaxial cervical spine isolated unilateral facet fractures.

PURPOSE To determine the variation in the global treatment practices for subaxial unilateral cervical spine facet fractures based on surgeon experience, practice setting, and surgical subspecialty. METHODS A survey was sent to 272 members of the AO Spine Subaxial Injury Classification System Validation Group worldwide. Questions surveyed surgeon preferences with regard to diagnostic work-up and treatment of fracture types F1-F3, according to the AO Spine Subaxial Cervical Spine Injury Classification System, with various associated neurologic injuries. RESULTS A total of 161 responses were received. Academic surgeons use the facet portion of the AO Spine classification system less frequently (61.6%) compared to hospital-employed and private practice surgeons (81.1% and 81.8%, respectively) (p = 0.029). The overall consensus was in favor of operative treatment for any facet fracture with radicular symptoms (N2) and for any fractures categorized as F2N2 and above. For F3N0 fractures, significantly less surgeons from Africa/Asia/Middle East (49%) and Europe (59.2%) chose operative treatment than from North/Latin/South America (74.1%) (p = 0.025). For F3N1 fractures, significantly less surgeons from Africa/Asia/Middle East (52%) and Europe (63.3%) recommended operative treatment than from North/Latin/South America (84.5%) (p = 0.001). More than 95% of surgeons included CT in their work-up of facet fractures, regardless of the type. No statistically significant differences were seen in the need for MRI to decide treatment. CONCLUSION Considerable agreement exists between surgeon preferences with regard to unilateral facet fracture management with few exceptions. F2N2 fracture subtypes and subtypes with radiculopathy (N2) appear to be the threshold for operative treatment

Health professionals’ perspective on the applicability of AO Spine PROST (patient reported outcome Spine trauma) in people with a motor-complete traumatic or non-traumatic spinal cord injury

Purpose: The AO Spine PROST (Patient Reported Outcome Spine Trauma) was developed for people with spine trauma and minor or no neurological impairment. The purpose is to investigate health professionals’ perspective on the applicability of the AO Spine PROST for people with motor-complete traumatic or non-traumatic spinal cord injury (SCI), using a discussion meeting and international survey study. Methods: A discussion meeting with SCI rehabilitation physicians in the Netherlands was performed, followed by a worldwide online survey among the AO Spine International community, involved in the care of people with SCI. Participants rated the comprehensibility, relevance, acceptability, feasibility and completeness of the AO Spine PROST on a 1–5 point scale (5 most positive). Comments could be provided per question. Results: The discussion meeting was attended by 13 SCI rehabilitation physicians. The survey was completed by 196 participants. Comprehensibility (mean ± SD: 4.1 ± 0.8), acceptability (4.0 ± 0.8), relevance (3.9 ± 0.8), completeness (3.9 ± 0.8), and feasibility (4.1 ± 0.7) of the AO Spine PROST were rated positively for use in people with motor-complete traumatic or non-traumatic SCI. Only a few participants questioned the relevance of items on the lower extremities (e.g., walking) or missed items on pulmonary functioning and complications. Some recommendations were made for improvement in instructions, terminology and examples of the tool. Conclusion: Health professionals found the AO Spine PROST generally applicable for people with motor-complete traumatic or non-traumatic SCI. This study provides further evidence for the use of the AO Spine PROST in spine trauma care, rehabilitation and research, as well as suggestions for its further development.</p

An international validation of the AO spine subaxial injury classification system.

PURPOSE To validate the AO Spine Subaxial Injury Classification System with participants of various experience levels, subspecialties, and geographic regions. METHODS A live webinar was organized in 2020 for validation of the AO Spine Subaxial Injury Classification System. The validation consisted of 41 unique subaxial cervical spine injuries with associated computed tomography scans and key images. Intraobserver reproducibility and interobserver reliability of the AO Spine Subaxial Injury Classification System were calculated for injury morphology, injury subtype, and facet injury. The reliability and reproducibility of the classification system were categorized as slight (ƙ = 0-0.20), fair (ƙ = 0.21-0.40), moderate (ƙ = 0.41-0.60), substantial (ƙ = 0.61-0.80), or excellent (ƙ = > 0.80) as determined by the Landis and Koch classification. RESULTS A total of 203 AO Spine members participated in the AO Spine Subaxial Injury Classification System validation. The percent of participants accurately classifying each injury was over 90% for fracture morphology and fracture subtype on both assessments. The interobserver reliability for fracture morphology was excellent (ƙ = 0.87), while fracture subtype (ƙ = 0.80) and facet injury were substantial (ƙ = 0.74). The intraobserver reproducibility for fracture morphology and subtype were excellent (ƙ = 0.85, 0.88, respectively), while reproducibility for facet injuries was substantial (ƙ = 0.76). CONCLUSION The AO Spine Subaxial Injury Classification System demonstrated excellent interobserver reliability and intraobserver reproducibility for fracture morphology, substantial reliability and reproducibility for facet injuries, and excellent reproducibility with substantial reliability for injury subtype

Development of Online Technique for International Validation of the AO Spine Subaxial Injury Classification System.

STUDY DESIGN Global cross-sectional survey. OBJECTIVE To develop and refine the techniques for web-based international validation of fracture classification systems. METHODS A live webinar was organized in 2018 for validation of the AO Spine Subaxial Injury Classification System, consisting of 35 unique computed tomography (CT) scans and key images with subaxial spine injuries. Interobserver reliability and intraobserver reproducibility was calculated for injury morphology, subtype, and facet injury according to the classification system. Based on the experiences from this webinar and incorporating rater feedback, adjustments were made in the organization and techniques used and in 2020 a repeat validation webinar was performed, evaluating images of 41 unique subaxial spine injuries. RESULTS In the 2018 session, the AO Spine Subaxial Injury Classification System demonstrated fair interobserver reliability for fracture subtype (κ = 0.35) and moderate reliability for fracture morphology and facet injury (κ=0.45, 0.43, respectively). However, in 2020, the interobserver reliability for fracture morphology (κ = 0.87) and fracture subtype (κ = 0.80) was excellent, while facet injury was substantial (κ = 0.74). Intraobserver reproducibility for injury morphology (κ =0.49) and injury subtype/facet injury were moderate (κ = 0.42) in 2018. In 2020, fracture morphology and subtype reproducibility were excellent (κ =0.85, 0.88, respectively) while reproducibility for facet injuries was substantial (κ = 0.76). CONCLUSION With optimized webinar-based validation techniques, the AO Spine Subaxial Injury Classification System demonstrated vast improvements in intraobserver reproducibility and interobserver reliability. Stringent fracture classification methodology is integral in obtaining accurate classification results

Establishing the Injury Severity of Subaxial Cervical Spine Trauma: Validating the Hierarchical Nature of the AO Spine Subaxial Cervical Spine Injury Classification System.

STUDY DESIGN Global cross-sectional survey. OBJECTIVE To validate the AO Spine Subaxial Cervical Spine Injury Classification by examining the perceived injury severity by surgeon across AO geographical regions and practice experience. SUMMARY OF BACKGROUND DATA Previous subaxial cervical spine injury classifications have been limited by subpar interobserver reliability and clinical applicability. In an attempt to create a universally validated scheme with prognostic value, AO Spine established a subaxial cervical spine injury classification involving four elements: (1) injury morphology, (2) facet injury involvement, (3) neurologic status, and (4) case-specific modifiers. METHODS A survey was sent to 272 AO Spine members across all geographic regions and with a variety of practice experience. Respondents graded the severity of each variable of the classification system on a scale from zero (low severity) to 100 (high severity). Primary outcome was to assess differences in perceived injury severity for each injury type over geographic regions and level of practice experience. RESULTS A total of 189 responses were received. Overall, the classification system exhibited a hierarchical progression in subtype injury severity scores. Only three subtypes showed a significant difference in injury severity score among geographic regions: F3 (floating lateral mass fracture, p:0.04), N3 (incomplete spinal cord injury, p:0.03), and M2 (critical disk herniation, p:0.04). When stratified by surgeon experience, pairwise comparison showed only 2 morphological subtypes, B1 (bony posterior tension band injury, p:0.02) and F2 (unstable facet fracture, p:0.03), and one neurologic subtype (N3, p:0.02) exhibited a significant difference in injury severity score. CONCLUSIONS The AO Spine Subaxial Cervical Spine Injury Classification System has shown to be reliable and suitable for proper patient management. The study shows this classification is substantially generalizable by geographic region and surgeon experience; and provides a consistent method of communication among physicians while covering the majority of subaxial cervical spine traumatic injuries.Level of Evidence: 4