Anterior-posterior Compression Research Articles

Diagnostic accuracy of MRI for detection of occult instability of type I anterior to posterior pelvic injuries

Type I Young and Burgess anterior posterior compression (APC) pelvic injuries have been classically managed non operatively due to theoretical integrity of sacroiliac joint ligaments (SIJL), though examination under anesthesia (EUA) has been proven occult mechanical instability in up to 50% of these injuries. We sought to determine the diagnostic accuracy of magnetic resonance (MRI) for detection of occult instability on APC-I injuries when compared to EUA.Methods: Diagnostic test study of prospectively recruited patients admitted with APC-I pelvic injuries between 2015 and 2022. All patients consented to participate in this study were subjected to MRI and EUA. The evaluators of each of these tests were blinded. On MRI evaluation, SIJL were considered compromised when unilateral injury to anterior SIJL was visualized in three or more consecutive images or in bilateral injuries, when injury to the anterior SIJL in two or more consecutive images on each side was observed. Positive EUA was considered a symphyseal diastasis over 25 mm on stress fluoroscopy. Demographic data was collected as recruited and sensitivity, specificity, accuracy, and positive and negative predictive values were calculated. Confidence interval was set at 95%. EUA was considered the gold standard in statistical analysis.Results: A total of 32 patients mean aged 36 (24–61) years were included. Mean symphyseal diastasis at admission was 17.58 (11 - 25) mm. The median time from injury to EUA was 5 (0–21) days. Positive EUA was observed on 20 patients and 25 patients presented compromised SIJL. MRI presented a sensitivity of 95% (75.13% - 99.87%), specificity of 50% (21.09% - 78.91%), positive-predictive value of 73% (60.61% to 82.93%), negative-predictive value of 87% (48.66% - 98.08%).Conclusion: Injury to SIJL on MRI presented an accuracy of 77% (58.29% - 89.64%) for the detection of occult pelvic instability on EUA.

Relationships Between Laryngoscopic Analysis Metrics of Supraglottic Compression and Vocal Effort in Primary Muscle Tension Dysphonia

Supraglottic compression is thought to underlie vocal effort in patients with primary muscle tension dysphonia (pMTD). However, the relationship between supraglottic compression and vocal effort in this clinical population remains unclear. Gold standard laryngoscopic assessment metrics for supraglottic compression are also lacking. The goals of this study were to identify metrics proposed in the literature that could distinguish patients diagnosed with pMTD from typical voice users and determine their relationships to the vocal effort. Flexible laryngeal endoscopy was performed on 50 participants (25 pMTD, 25 controls). The presence of supraglottic compression was characterized using a categorical (nominal) scale and severity was quantified on ordinal and continuous scales. The three laryngoscopic metrics were correlated with self-perceived ratings of vocal effort on a 100mm visual analog scale. Inter-rater reliability was strongest for the continuous scale (P's<0.0001) compared to categorical (P's<0.001) and ordinal (P's<0.001) scales. The presence of different supraglottic compression patterns varied in both groups, and there were no significant group differences on categorical (P's>0.05) scales. Mediolateral (M-L) supraglottic compression was significantly greater in the pMTD group (P<0.0001), and anteroposterior(A-P) compression was significantly greater in the control group (P=0.001) using continuous scales. There were no significant relationships between any of the three laryngoscopic metric types and vocal effort ratings (P's>0.05), except for a significantly positive relationship between anterior-posterior compression on the ordinal scale and vocal effort in the control group (P=0.047). Continuous scales are reliable and valid for distinguishing individuals with pMTD from those without voice disorders, especially occupational voice users. M-L supraglottic compression may be a better indicator of pMTD than A-P compression. However, the poor correlation between supraglottic compression and vocal effort suggests that one may not influence the other. Future studies should focus on other mechanisms underlying vocal effort in patients with pMTD.

136 Morphological Clusters of Chiari I Patients With Variable Response After Suboccipital Decompression

INTRODUCTION: Chiari malformation type I (CM-I) can cause debilitating neurologic symptoms, most notably distinctive headaches, and the only existing definitive treatment is suboccipital decompression. While CM-I is typically defined as ≥5 mm downward displacement of cerebellar tonsils, overall CM-I cerebellar morphology is highly heterogeneous, and it is uncertain if this variability represents distinct patient populations or influences clinical response to suboccipital decompression. METHODS: 186 adult CM-I patients with high-resolution T1-MRIs were retrospectively identified. Each patient’s cerebellum was non-linearly and diffeomorphically transformed to template brain, with this transformation’s inverse representing cerebellar deformation. A similarity matrix was generated between patients’ deformations using the Pearson correlation coefficient of their inverse transformations’ log Jacobian determinants within each cerebellar lobule. Spectral clustering was performed on this similarity matrix to identify patient clusters. Headache freedom after suboccipital decompression was compared between clusters by Kaplan-Meier analysis. RESULTS: Three morphological clusters of CM-I patients were identified. Cluster A is characterized by posteroinferior cerebellar fullness and platybasia; B by midline anterior-posterior compression; C solely by tonsillar descent. After suboccipital decompression, headaches were found to recur more frequently and sooner in Cluster B (p &lt; 0.01). CONCLUSIONS: These analyses suggest that CM-I encapsulates morphologically distinct subtypes, here identified as Cluster A and Cluster B, with Cluster C representing an intermediate phenotype. These clusters vary significantly in clinical response to suboccipital decompression, which may have implications for surgical patient selection or operative technique. Future research should involve independent validation of this cluster scheme and optimization of treatment for patients in Cluster B, which is found here to have poorer surgical outcomes.

A cadaveric biomechanical evaluation of anterior posterior compression II injuries

Pelvic fractures are associated with high morbidity and often require surgical intervention. An Anterior Posterior Compression (APC) II injury consists of disruption at the pubic symphysis and anterior sacroiliac joint. Studies investigating specific ligamentous contributions would aid in development of novel fixation techniques. The objective of this study is to determine the level of pelvic destabilization from progressive soft tissue disruptions associated with APC II injuries. Six fresh-frozen cadaveric pelvises were dissected of soft tissues, preserving joint capsules and ligaments. Each pelvis was secured in a double-leg stance and joint motion was tracked with the specimens cyclically loaded to 60% body weight. Each specimen was measured in the intact state and again following stepwise destabilization to an APC II injury model (PS: sectioned pubic symphysis, IPS JOINT: PS+ipsilateral anterior sacroiliac, sacrotuberous, sacrospinous ligaments sectioned, IPS LIGS: IPS JOINT+ipsilateral interosseous ligaments sectioned, IPS JOINT+CONT ASI: IPS LIGS+contralateral anterior sacroiliac ligament disruption). Compared to the intact state, there was a statistically significant increase in movement in the IPS JOINT (ipsilateral 177%, p<0.001; contralateral 46%, p<0.005) and IPS JOINT+CONT ASI (ipsilateral 184%, p<0.002; and contralateral 62%, p<0.002) states bilaterally. No significant change was demonstrated in the PS or IPS LIGS state. Disruption of ipsilateral ligamentous structures destabilized both sacroiliac joints. The interosseous and posterior sacroiliac ligaments provide the majority of stability of the sacroiliac joint and will likely benefit most from surgical stabilization. mechanism-based reasoning.

A biomechanical comparison of superior ramus plating versus intramedullary screw fixation for unstable lateral compression pelvic ring injuries,,,

IntroductionManagement of the anterior component of unstable lateral compression (LC) pelvic ring injuries remains controversial. Common internal fixation options include plating and superior pubic ramus screws. These constructs have been evaluated in anterior-posterior compression (APC) fracture patterns, but no study has compared the two for unstable LC patterns, which is the purpose of this study. MethodsA rotationally unstable LC pelvic ring injury was modeled in 10 fresh frozen cadaver specimens by creating a complete sacral fracture, disruption of posterior ligaments, and ipsilateral superior and inferior rami osteotomies. All specimens were repaired posteriorly with two fully threaded 7 mm cannulated transiliac-transsacral screws through the S1 and S2 corridors. The superior ramus was repaired with either a 3.5 mm pelvic reconstruction plate (n = 5) or a bicortical 5.5 mm cannulated retrograde superior ramus screw (n = 5). Specimens were loaded axially in single leg support for 1000 cycles at 400 N followed by an additional 3 cycles at 800 N. Displacement and angulation of the superior and inferior rami osteotomies were measured with a three-dimensional (3D) motion tracker. The two fixation methods were then compared with Mann-Whitney U-Tests. ResultsRetrograde superior ramus screw fixation had lower average displacement and angulation than plate fixation in all categories, with the motion at the inferior ramus at 800 N of loading showing a statistically significant difference in angulation. ConclusionAlthough management of the anterior ring in unstable LC injuries remains controversial, indications for fixation are becoming more defined over time. In this study, the 5.5 mm cannulated retrograde superior ramus screw significantly outperformed the 3.5 mm reconstruction plate in angulation of the inferior ramus fracture at 800 N. No other significance was found, however the ramus screw demonstrated lower average displacements and angulations in all categories for both the inferior and superior ramus fractures.

Suprachoroidal Hemorrhage and Choroidal Rupture

Suprachoroidal hemorrhage (SCH) is a rare but potentially vision-threatening, feared complication of intraocular surgery. It is defined as the accumulation of blood in the potential space between the choroid and sclera by the rupture of the long or short posterior ciliary arteries or vortex veins due to sudden low intraocular pressure (IOP). Choroidal rupture is the rupture of the inner choroid, the overlying Bruchs membrane, and the RPE due to blunt eye trauma. After blunt trauma that causes anterior-posterior compression, the globe suddenly expands in the horizontal direction and crescent-shaped cracks are formed centered on the optic disc. In this section, suprachoroidal hemorrhage (SCH) and choroidal rupture will be mentioned.

The Influence of Voice Training on Vocal Learners’ Supraglottal Activities and Aerodynamic Evaluation

Among music majors with only 18 months of training, supraglottal activities and aerodynamic parameters were studied to facilitate understanding of the influence of voice training on characteristics of voice production. Twenty-three students at the Xiamen Music School were examined over the course of 18 months of singing training. Only 17 students completed all data collection sessions. All students had no previous voice training and were confirmed to be without organic voice disorders by a laryngologist but did present with supraglottal compression. Strobolaryngoscopy and aerodynamic assessment were performed every 6 months. Using the laryngoscopic images, anterior-posterior (A-P) compression and medial-lateral compression were analyzed. Aerodynamic assessment was carried out to measure maximum phonation time, phonation threshold flow, glottal resistance, subglottal pressure, phonation threshold pressure, and vocal efficiency. From these measurements, the mean was calculated along with a measurement of reliability. One-way ANOVA with Bonferroni post hoc test was used to evaluate the results between subjects at different time points. Kendall's W test was completed to assure consistency between and within laryngologists. Referring to the Strobolaryngoscopy Evaluation Rating Form, 4 of the 17 students had decreased A-P compression scores in the second measurement compared to the first (from 2.24 ± 0.20 to 2.12 ± 0.17, P = 0.100). After completion of the program, 6 of the 17 students' anterior-posterior compression scores further improved from the second measurement (from 2.12 ± 0.17 to 1.71 ± 0.17, P = 0.600). The A-P compression scores showed a gradual downward trend and was overall statistically significant (P = 0.004). In addition, there was an improvement of maximum phonation time (P​ ​= 0.016). Professional voice training can improve the supraglottal activities and maximum phonation time. These parameters have potential to be used for voice training evaluation and screening.

1085 Equestrian Related Pelvic and Acetabular Fractures – Experience from a Major Trauma Centre in England

Abstract Introduction Equestrianism is enjoyed by three million people in the UK; however, there is a lack of literature on pelvic and acetabular (P&amp;A) injuries incurred through the sport. We aim to describe P&amp;A injuries sustained in equestrian accidents, discuss management, and establish their outcomes. Method Data was extracted from a prospectively collected database of referrals to the P&amp;A Service of a Major Trauma Centre (MTC) from 01/01/2016 to 31/12/2020 and cross-referenced with medical records. Results 60 of the 1,218 P&amp;A referrals were secondary to horse-riding accidents. Mean age 45 (SD 16.59); 46 female; 33 managed non-operatively and 27 managed operatively at the MTC. There was sufficient information for 59 cases to be classified; 46 of the injuries were pelvic fractures (10 anterior-posterior compression; 29 lateral compression; 4 sacral and 3 pubic rami fractures) and 13 were acetabular (2 anterior column; 1 anterior wall; 2 associated both columns; 1 posterior column and posterior wall; 1 posterior wall; 2 T-shaped and 4 transverse fractures). The operative group were managed by examination under anaesthesia (n = 3), open reduction internal fixation (n = 22) or percutaneous fixation (n = 2). Mean hospitalisation was 9.2 days (SD 5.44). 81% were non-weight-bearing post-operatively and mean time to independent mobilisation was 12.6 weeks (SD 7.09). Return-to-riding information was available for 8 patients with a mean of 29.5 weeks (SD 11.55). Conclusions Equestrianism can result in significant P&amp;A injuries. Patients should be counselled that they may have a long recovery, a protracted return-to-riding time and some may never return to the sport.

Biomechanical strength dependence on mammalian airway length.

BackgroundThe trachea is the uppermost respiratory airway element connecting the larynx to the bronchi Airway reconstructions in humans are often developed from animal models but there is limited knowledge comparing tracheal biomechanics between species. We aimed to assess the structure and biomechanics of porcine, canine, caprine and human airways.MethodsTracheas from pigs (n=15), goats (n=9) and canines (n=9) were divided into three groups (4, 6 and 8-ringswhile human left principal brochi (n=12) were divided into two groups (3and-rings). Airway structures were compared using histology and scanning electron microscopy. Biomechanical properties were measured subjecting samples to uniaxial tension and compression, recording the elastic modulus and (tensile and compressive) strengths.ResultsThe structures of animal tracheal and human bronchia appeared similar. Biomechanical testing revealed that the elastic modulus of 8-ring tracheas was 1,190.48±363.68, 2,572.00±608.19 and 1,771.27±145.54 kPa, for porcine, canine and caprine samples, respectively, while corresponding tensile strengths were 437.63±191.41, 808.38±223.48 and 445.76±44.00 kPa. Comparable measures of anterior-posterior (A-P) compression strengths were 7.94±0.82, 7.54±0.07 and 8.10±1.87 N, respectively, whereas lateral compression strengths were 8.75±0.82, 14.55±2.29 and 11.12±0.40 N. Compression testing of human samples showed significant differences (P<0.05) between the 3-ring (A-P, 1.06±0.02 N; lateral, 0.55±0.06 N) and 5-ring groups (A-P, 1.08±0.64 N; lateral, 2.32±1.95 N).ConclusionsThe tensile and compressive strengths of mammalian airways show positive correlations with the cartilage ring number (length). On the basis of structural and biomechanical comparisons, porcine, canine and caprine species appear suitable models for the study of airway reconstruction in human.

A biomechanics study on ligamentous injury in anterior-posterior compression type II pelvic injury

BackgroundAnterior-posterior compression (APC) type II pelvis fracture is caused by the destruction of pelvic ligaments. This study aims to explore ligaments injury in APC type II pelvic injury.MethodFourteen human cadaveric pelvis samples with sacrospinous ligament (SPL), sacrotuberous ligament (SBL), anterior sacroiliac ligament (ASL), and partial bone retaining unilaterally were acquired for this study. They were randomly divided into hemipelvis restricted and unrestricted groups. We recorded the separation distance of the pubic symphysis and anterior sacroiliac joint, external rotation angle, and force when ASL ruptured. We observed the external rotation damage to the pelvic bone and ligaments.ResultWhen ASL failed, there was no significant difference in pubic symphysis separation (28.6 ± 8.4 mm to 23.6 ± 8.2 mm, P = 0.11) and anterior sacroiliac joint separation (11.4 ± 3.8 mm to 9.7 ± 3.9 mm, P = 0.30) between restricted and unrestricted groups. The external rotation angle (33.9 ± 5.5° to 48.9 ± 5.2°, P < 0.01) and force (553.9 ± 82.6 N to 756.6 ± 41.4 N, P < 0.01) were significantly different. Pubic symphysis separation between two groups ranged from 14 to 40 mm. In the restricted group, both SBL and SPL were injured. SPL ruptured first, and then SBL and the interosseous sacroiliac ligament were damaged while the posterior ligament remained unharmed. In the unrestricted group, interosseous sacroiliac ligament and posterior sacroiliac ligaments were damaged, while SBL and SPL were not. When the ASL, SBL, and SPL all failed, pubic symphysis and anterior sacroiliac joint separation between two groups increased significantly (from 28.6 ± 8.4 to 42.0 ± 7.6 mm, 11.4 ± 3.8 to 16.7 ± 4.2 mm respectively, all P < 0.05).ConclusionPelvic external rotation injury is either hemipelvic restricted or unrestricted, which can result in different outcomes. When the ASL ruptures, the unrestricted group needs greater external rotation angle and force, without SBL or SPL injury, while both SBL and SPL were injured in another group. When ASL fails in two groups, pubic symphysis separation fluctuates considerably. Finally, when the ASL ruptures, SBL and SPL may be undamaged.

Epidemiology of surgically treated pelvis and acetabulum fractures in a Level-1 trauma centre in Oman

Objective: The purpose of this study is to analyze the epidemiological characteristics of operated pelvic and acetabular fractures at our institution and to compare them with epidemiological data from different parts of the world. Methods: This is a retrospective study of trauma data at Khoula Hospital from January 2010 to December 2016. Epidemiological data including age, gender, mode of trauma, presence of injuries, fracture classification, surgical approach, and associated complications were analyzed. Results: A total of 209 patients with a diagnosis of pelvis and acetabular fracture were included in this study. Young age group (mean: 35) and male gender (68%) were predominately affected. The main leading cause of the injury was road traffic accidents (96%). There were a total of 179 (86%) acetabular fractures and 30 (14%) pelvic fractures. Fracture of the posterior wall of the acetabulum was the most common pattern (39%), followed by transverse fracture (27%). Anterior–posterior compression type was clearly the most common type of pelvis fracture (40%). Six patients had postoperative sciatic nerve palsy, five patients had venous thromboembolism, and nine patients had wound infection. Conclusion: The great majority of the patients were victims of road traffic accidents, male, and young adults. The posterior wall fracture was the most common pattern, as shown in other studies as well. However, we identified some epidemiological differences in comparison with some studies from some other parts of the world. These include a higher contribution of road traffic accidents as a mode of injury and a high female-to-male ratio.

Association between Young-Burgess pelvic ring injury classification and concomitant injuries requiring urgent intervention

BackgroundYoung-Burgess classification (YB) is a mechanistic system which classifies pelvic ring injuries into anterior-posterior compression (APC), lateral compression (LC), vertical shear (VS) injuries, and combined mechanism (CM). The objective of this study was to identify associated injuries which require urgent operative intervention by YB classification. We hypothesize that YB classification is associated with 1) need for urgent intervention for pelvic fracture-related hemorrhage and 2) patterns of injury complexes requiring surgery. MethodsThis is a retrospective study of severely injured trauma patients with pelvic ring injuries who presented to an urban Level-1 trauma center from 2007 to 2017. Associated injuries and procedures were determined by Abbreviated Injury Scale (AIS) and ICD-9/10 codes. YB classes were compared, followed by a cluster analysis to identify injury patterns and association with YB classifications. ResultsOverall, 135 patients were included. 98 (72%) of patients presented with LC, 16 (12%) with APC, 8 (6%) with VS, and 13 (10%) with CM. VS and APC groups had higher rates of REBOA use compared to LC and CM groups (38% and 31% versus 11% and 0%, respectively, p = 0.01). The CM group, compared to LC, APC, and VS, had higher rates of urgent operative intervention for bleeding control (69% versus 32%, 50% and 43%, respectively, p = 0.01). 39 (29%) patients had a concomitant injury which was identified by CT scan in initial trauma work up and altered management, 46% which merited urgent intervention. On cluster analysis, there were no distinct injury complexes which required urgent operative intervention by YB class. ConclusionsThese data failed to identify unique injury complexes which merit urgent operative intervention by YB class. Nearly one in four patients had injuries identified by initial CT imaging which altered initial management, demonstrating the importance of early, full body CT imaging in severely injured patients with pelvic ring injuries.

Maternal Fetal Health

Maternal Fetal Health

Similar patient reported outcomes at long-term follow-up after external fixation versus internal fixation of the anterior ring component of APC injuries

Purpose: Unstable pelvic ring injuries produced by external rotation of the hemipelvis and a symphyseal disruption are most often treated with internal fixation of the anterior ring, with percutaneous treatment of the posterior ring as needed. In some clinical situations, patients are treated with external fixation for their anterior injuries and the long-term functional outcomes associated with external fixation are not well understood. We ask if there is a difference in functional outcome, between treatment of these injuries with internal versus external fixation, when measured at a minimum of three years after injury.Method: This was a retrospective cohort study performed at a level one regional trauma center. Trauma database review identified 128 patients, with 70 subsequently excluded, with unstable anterior posterior compression (APC) pelvic ring injuries (OTA 61B2.3 & 61C1.2) treated with surgery with minimum three years of follow-up. An intervention of internal fixation versus external fixation of anterior pelvic ring was performed, and depending on the injury, supplemented with posterior iliosacral screw fixation. Main outcome was measured with the Majeed functional outcome score (0-100).Results: Patients treated with external fixation reported a Majeed score of 70 (95% CI 28-100) compared to 79 (95% CI 36-100) in those with internal fixation (p-value 0.28). Subgroups of the Majeed score were not significantly different (p value > 0.05). Open fractures, severity of injury, and ISS were worse in those treated with external fixation. There was no differential loss to follow-up.Conclusion Patients with unstable pelvic ring injuries with symphyseal disruptions treated with external fixation as definitive treatment versus internal fixation may fare no different in the long term.

The use of external fixation in the emergency department: applications, common errors, complications and their treatment.

The use of an external fixator (EF) in the emergency department (ED) or the emergency theatre in the ED is reserved for critically ill patients in a life-saving attempt. Hence, usually only fixation/stabilization of the pelvis, tibia, femur and humerus are performed. All other external fixation methods are not indicated in an ED and thus should be performed in the operating room with a sterile environment.Anterior EF is used in unstable pelvic lesions due to anterior-posterior compression, and in stable pelvic fractures in haemodynamically unstable patients.Patients with multiple trauma should be stabilized quickly with EF.The C-clamp has been designed to be used in the ED to stabilize fractures of the sacrum or alterations of the sacroiliac joint in patients with circulatory instability.Choose a modular EF that allows for the free placement of the pins, is radiolucent and is compatible with magnetic resonance imaging (MRI).Planning the type of framework to be used is crucial.Avoid mistakes in the placement of EF.Cite this article: EFORT Open Rev 2020;5:204-214. DOI: 10.1302/2058-5241.5.190029

Feasibility of Early Definitive Internal Fixation of Pelvic Bone Fractures in Therapeutic Open Abdomen

Purpose: Damage control laparotomy has contributed to improved survival rates for severe abdominal injuries. A large part of severe abdominal injury occurs with a concomitant pelvic bone fracture. The safety and effectiveness of internal fixation of pelvic bone fracture(s) has not been established. The aim of the present study was to evaluate infection risk in the pelvic surgical site in patients who underwent emergent abdominal surgery. Methods: This single-center retrospective observational study was based on data collected from a prospectively maintained registry between January 2015 and June 2019. Patients who underwent laparotomy and pelvic internal fixation were included. Individuals <18 and ≥80 years of age, those with no microbiological investigations, and those who underwent one-stage abdominal surgery were excluded. Comprehensive statistical comparative analysis was not performed due to the small number of enrolled patients. Results: A total of six patients met the inclusion criteria, and the most common injury mechanism was anterior-posterior compression (67%). The average duration of open abdomen was 98 hours (range, 44-198), and the time interval between abdominal closure and pelvic surgery was 98 hours. One patient (16.7%) died due to multi-organ dysfunction syndrome. Micro-organisms were identified in the abdominal surgical site in five patients (83%), with no micro-organisms in pelvic surgical sites. There was no unplanned implant removal. Conclusions: Internal fixation of pelvic bone fracture(s) could be performed in the state of open abdomen, and the advantages of early fixation may countervail the risks for cross contamination.

Chest Injury-football

HISTORY: 17 year old high school football wide receiver presented with left back and rib pain. He sustained a hit in that region during a football game the night before. He was taken out of the game due to pain and difficulty breathing which ultimately kept him from finishing the game. After the game he continued to have pain for which he took a muscle relaxant that he had from a previous injury and over the counter pain medication with minimal pain relief. The pain persisted through the night and into the following morning. His pain was worse with deep breathing and any pressure on his chest. He denied any shortness of breath, dyspnea with exertion, cough, wheezing or hemoptysis. PHYSICAL EXAMINATION: Appeared in no acute distress, Ecchymosis over the posterior lateral aspect of left lower ribs with tenderness to palpation, No crepitus, No palpable deformity, Symmetric chest expansion, posterior rib/back pain reproduced with deep inspiration, Equal bilateral breath sounds, No hyper-resonance to percussion, Normal respiratory rate, Negative anterior posterior compression test, Positive lateral compression test, Full AROM of the back DIFFERENTIAL DIAGNOSIS: Rib fracture, Pneumothorax, Pulmonary contusion, Pulmonary embolism TEST AND RESULTS: X-ray Rib series: Small left apical pneumothorax involving approximately 20% of the hemi thorax. Suspected nondisplaced fractures involving the posterolateral left eighth and ninth ribs with small linear lucencies within these regions. Chest CT scan: Small left-sided pneumothorax approximately 20%. No acute osseous injury. FINAL WORKING DIAGNOSIS: Pneumothorax TREATMENT AND OUTCOMES: The patient was sent to ER after being seen in clinic to expedite getting a CT scan done after the X-rays. After the CT scan was obtained it was decided by the ED to admit the patient for observation. He obtained a subsequent x-ray that evening 12 hours after is initial which showed a slightly smaller left apical pneumothorax. He was discharged the next day. Repeat chest x-ray done three days after discharge showed improving pneumothorax. Patient was seen in clinic 2 weeks after his discharge from the hospital and was started on a graded exercise program with repeat x-ray at 1 week after clinic visit showed resolution of pneumothorax. He returned to full game play at 4 weeks after his initial injury.

How Does Cage Lordosis Influence Postoperative Segmental Lordosis in Lumbar Interbody Fusion

Consideration of sagittal alignment is an integral part of spinal fusion surgery correlating with superior outcomes. Segmental lordosis is an important contributor to sagittal alignment. This study assessed surgical factors influencing segmental lordosis in a 360° fusion model, including cage dimensions, anterior longitudinal ligament resection, facetectomy, and posterior compression. Six L3-4 synthetic spinal motion segments were used in a repeated measures design. Each sample was sequentially instrumented with lateral cages of increasing height and angle. Lordosis was assessed from lateral radiographs of intact and each instrumented condition. The effect of anterior longitudinal ligament resection, posterior compression with pedicle screws, and bilateral facetectomy was additionally examined. A linear relationship between segmental lordosis and cage height was found. This effect was greater with the anterior longitudinal ligament divided. In cages of the same anterior height, increased intrinsic cage lordosis did not result in increased segmental lordosis; cages with no intrinsic lordosis resulted in the highest segmental lordosis. In examining this finding, it was shown that posterior cage height had a larger influence on segmental lordosis. Posterior compression with pedicle screws and bilateral facetectomy increased the segmental lordosis by a further 3.4° and 2.6°, respectively. Cage height was a key factor, with posterior compression further increasing lordosis. The finding that 0° cages results in the most segmental lordosis was an unexpected finding and highlights the importance of appropriate sizing on resulting lordosis. These findings are relevant to cage selection but require further study prior to applying to clinical practice and may influence future cage design.

Unstable Pelvic Ring Injuries: How Soon Can Patients Safely Bear Weight?

To determine if time to weight bearing (WB) is associated with complications in operatively treated pelvic ring injuries. Retrospective cohort study. Academic Level I trauma hospital. Two hundred eighty-six patients with pelvic ring injuries treated operatively over a 10-year period [OTA/AO 61-B1-3, 61-C1-3; Young-Burgess lateral compression (LC) 1-3, anterior-posterior compression (APC) 1-3, and vertical shear] were included. Patients were stratified into early (≤8 weeks) and late (>8 weeks) time to full WB groups. Composite outcome of implant failure [broken screw(s)/plate(s), screw(s) loosening], revision surgery, and malunion. We identified 286 patients with a mean age of 39.9 years (range: 18-81 years) and an average follow-up of 1.2 years (1.0-9 years). There were 132 and 154 patients in the early and late WB groups, respectively. A total of 142 Young-Burgess LC-1, 48 LC-2, 23 LC-3, 10 APC-1, 45 APC-2, 8 APC-3, and 8 vertical shear injuries were noted. Complications were noted in 47 patients (16%). Complications included 18 implant failures, 16 malunions, and 13 patients who required revision operations for loss of reduction. Time to WB was not associated with composite complication rates (P = 0.24). APC-2, LC-3, and injuries with bilateral rami fractures were noted to have a higher complication rates independent of time to WB (P = 0.005, 0.03, and 0.03, respectively). No difference in implant failure, malunion, or early loss of reduction between operatively treated pelvic ring injuries allowed to WB as tolerated before 8 weeks compared with those who remained on protected WB protocol for any time greater than 8 weeks was noted. These data may provide information to support early WB protocols. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Effect of knee positions on cardiac compression variables in cardiopulmonary resuscitation of rescuer; Manikin study

The aim of the study was to analyze the effect of knee positions on cardiac compression variables in cardiopulmonary resuscitation (CPR) using the manikin. Adult with career of CPR instructor (n=9; mean age, 27.11±6.60 years; mean heights, 177.39±4.40 cm; mean weights, 69.45±14.85 kg) participated in the experiment, and each participant performed cardiac compression from two different knee positions. Cardiac compression was 30 times per minute for each position with order of position randomized. The results obtained from variables of cardiac compression force were composed of compression velocity, elapsed time, decay rate, and loading rate in maximum and minimum medial-lateral, anterior-posterior (AP), vertical direction respectively. The above variables in 20.3 cm of knee position showed effective result than that of 50 cm of knee position, while maximum AP compression force increased. Given the often predictable setting of sports and exercise rehabilitation related with cardiac arrest, CPR relative to change of knee position were significantly associated with more efficient cardiac compression variables. These data have significant implications for health services program in fields of sports and exercise rehabilitation.