Predominant Injury Research Articles

ASSOCIATION BETWEEN ANXIETY-DEPRESSIVE SPECTRUM DISORDERS AND JOINT DISEASE IN WOMEN

The frequency of anxiety-depressive spectrum disorders (ADSDs) in patients with rheumatic diseases (RDs) is much higher than that in the general population. ADSDs are known to be associated with pain intensity, disease activity, and functional limitations. However, the majority of available papers are limited by the framework of a certain disease. Objective: to investigate the association of ADSDs with the characteristics of joint damage beyond the nosological approach. Subjects and methods. The investigation enrolled 38 women aged 18 years and older who had different RDs and preserved reproductive function, were treated at round-the-clock hospitals, and had no clinically significant comorbid diseases. All the patients were divided into two subgroups: 1) those with predominant hand joint injury and 2) those with joint involvement at other sites. All the patients were evaluated for disease activity (DAS-28-ESR, ASDAS-ESR), pain (visual analogue scale), and functional status (HAQ). The Hospital Anxiety and Depression Scale (HADS) was used to detect ADSDs and the Hamilton Anxiety Rating Scale (HAM-A) and the Hamilton Depression Rating Scale were employed to rate the severity of anxiety and depression, respectively. Results and discussion. The frequency of anxiety disorders evaluated through the HADS and the HAM-A was 44.7 and 34.2%, that of depressions was 34.2 and 60.5% respectively. The clinically evident level of HADS anxiety (11+) in Subgroup 1 was detected 5 times more frequently (30.0%) than in Subgroup 2 (5.5%); and that of HAM-A anxiety (18+) was twice as often: 45.0 and 22.2%, respectively. The frequency of clinically significant depression according to HADS (11+) and HAM-D (14+) in Subgroup 1 was 30.0 and 40.0%, and that in Group 2 was 11.1 and 16.7% respectively. The probability of severe depressions (HAM-D 19+) in hand joint injury was twice higher (odds ratio, 2.2; 95% confidence interval, 1.51–3.19) than in arthritis at various sites. Thus, this investigation provides evidence for the high frequency of ADSDS in patients with RDs. Reproductive-aged women with hand joint injury are one of the most vulnerable groups.

Pattern of presentation of gastroesophageal reflux disease among patients with dyspepsia in Kano, Nigeria.

Background:Dyspepsia is a symptom complex rather than a specific disease entity. It can be caused by both organic and functional gastrointestinal (GI) disorders. Gastroesophageal reflux disease (GORD) though a common digestive disorder worldwide is scarcely reported in Nigeria. The aim of this study is to determine the pattern of presentation of GORD among patients with dyspepsia.Methods:One hundred and seventy dyspeptic patients were recruited consecutively as they were referred to the Gastroenterology Unit of Aminu Kano Teaching Hospital for upper GI endoscopy. A prepared questionnaire on relevant demographic and clinical history relating to GORD was administered. Upper GI endoscopy was then performed on each patient.Results:The prevalence of GORD was 24.1%, with a M:F ratio of 1:1.1. Endoscopy-positive variant accounted for 16 cases (9.4%), while endoscopy-negative variant accounted for 25 cases (14.7%), with of the total GORD patients, 26(63.4%) were males while 15(36.6%) were females. Los Angeles Grade A (37.5%) was the predominant endoscopic esophageal mucosal injury found in 6 cases. Barrett's esophagus and esophageal adenocarcinoma accounted 4.9% each and were considered to be rare. Extra-esophageal manifestations were also rare.Conclusions:Endoscopy-negative variant still remains the predominant endoscopic finding in GORD patients.

Maxillofacial fractures in a budding teaching hospital: a study of pattern of presentation and care.

IntroductionPrevious reports indicated that there is geographic and sociodemographic variation in the epidemiology of maxillofacial fractures. Audit of maxillofacial injuries managed at any institution is therefore necessary to understand the trends and proffer strategies for prevention. We therefore embarked on this study to determine the pattern of maxillofacial fractures and concomitant injuries in our institution.MethodsWe carried out a retrospective review of information on demography, aetiology and type of maxillofacial fracture, patients' status, type of crash, level of consciousness and concomitant injuries. The data collected was analysed with SPSS Version 20.ResultsA total of 233 patients aged 2 to 66 years were reviewed. A higher male preponderance (M:F 3.4:1) was observed. Road traffic crashes (RTC) accounted for 78.5% of injuries. Motorcycle related crashes were responsible for 69.4% of RTC and 54.5% of all fractures. Fracture of the mandible (63.2% n=172) was the most predominant skeletal injury and the body (25% n=43) was the most common site of fracture while the zygoma (29%) was predominantly affected in the midface. Ninety three patients (40%) suffered loss of consciousness. The relationship between aetiology of injuries and consciousness level of the patients was statistically significant (p=0.001). Of the 43 patients who had concomitant injuries, craniocerebral affectation (60.5%) was the commonest.ConclusionRTC remains the major aetiology of maxillofacial fractures. The mandible was mostly affected and nearly half of the patients have associated loss of consciousness. There is need for continual advocacy and enforcement of laws on preventive measures among road users.

Peripheral neuropathy of a forelimb in horses: 27 cases (2000-2013).

OBJECTIVE To describe the clinical features, diagnostic procedures, management, and outcome of horses with peripheral neuropathy of a forelimb. DESIGN Retrospective case series. ANIMALS 27 horses. PROCEDURES Records from 2000 to 2013 were reviewed to identify horses with peripheral neuropathy of a forelimb. Horses were grouped as having predominant lesions of a suprascapular nerve, axillary nerve, or radial nerve (alone or in association with other brachial plexus nerves) on the basis of physical examination and diagnostic imaging findings. Treatments were primarily conservative. Signalment, history, lameness characteristics, diagnostic imaging features, case management, and outcomes were evaluated. RESULTS Predominant lesions of a suprascapular nerve, axillary nerve, and radial nerve were identified in 11, 2, and 14 horses, respectively. Eight horses with predominant suprascapular nerve injury and 9 with injury to a radial nerve alone or in association with other nerves returned to their previous activity level or intended use after mean recovery periods of 9.3 and 13.3 months, respectively; 2 horses with a predominant axillary nerve injury had this outcome after a mean 3.5-month recovery period. Ultrasonography was useful for evaluation of muscle atrophy and other injuries during the initial examination (in 27 horses) and the rehabilitation period (in 7 horses). CONCLUSIONS AND CLINICAL RELEVANCE Most horses with peripheral neuropathy of a forelimb returned to athletic soundness following an adequate period of rest. Horses with lesions of a radial nerve alone or in association with other nerves typically required longer recovery times than did those with predominant injuries of a suprascapular nerve.

MRI classification system (MRICS) for children with cerebral palsy: development, reliability, and recommendations.

To develop and evaluate a classification system for magnetic resonance imaging (MRI) findings of children with cerebral palsy (CP) that can be used in CP registers. The classification system was based on pathogenic patterns occurring in different periods of brain development. The MRI classification system (MRICS) consists of five main groups: maldevelopments, predominant white matter injury, predominant grey matter injury, miscellaneous, and normal findings. A detailed manual for the descriptions of these patterns was developed, including test cases (www.scpenetwork.eu/en/my-scpe/rtm/neuroimaging/cp-neuroimaging/). A literature review was performed and MRICS was compared with other classification systems. An exercise was carried out to check applicability and interrater reliability. Professionals working with children with CP or in CP registers were invited to participate in the exercise and chose to classify either 18 MRIs or MRI reports of children with CP. Classification systems in the literature were compatible with MRICS and harmonization possible. Interrater reliability was found to be good overall (k=0.69; 0.54-0.82) among the 41 participants and very good (k=0.81; 0.74-0.92) using the classification based on imaging reports. Surveillance of Cerebral Palsy in Europe (SCPE) proposes the MRICS as a reliable tool. Together with its manual it is simple to apply for CP registers.

MRI Findings of Injury to the Longus Colli Muscle in Patients With Neck Trauma.

The longus colli muscle (LCM) forms the bulk of the deep flexor muscles of the neck. To our knowledge, very little information on the effects of trauma on this muscle group has been published. We describe MRI findings related to injury of the LCM in patients with a history of neck trauma. A radiology department database was searched to identify patient medical records from 2008 to 2013 that included the keywords "longus colli" and "deep flexors." Patients with fractures and ligament injuries were excluded. Patients with other obvious large soft-tissue injuries and nontraumatic conditions were also omitted. A total of 12 patients met the inclusion criterion of having an isolated or predominant injury to the LCM. Five patients had been involved in a motor vehicle accident, and seven patients had fallen. Eleven patients had undergone a CT examination before MRI was performed. No fractures were noted on CT. MRI examinations of the cervical spine were obtained for the following reasons: for increased prevertebral soft-tissue swelling noted on a CT scan plus neck pain (n = 6), for neck pain only (n = 4), or as part of a routine protocol for assessment of obtunded patients (n = 2). Eight of the 12 patients had isolated injury to the LCM. The remaining four patients also had minor injuries to the other neck muscles. The MR image showed swelling and T2 hyperintensity in the LCM and revealed free fluid in the prevertebral space. Isolated injury to the LCM may occur in neck injuries. The MRI findings indicating such injury include increased T2 signal, swelling of the muscle, and the presence of prevertebral fluid.

A Multicenter, Prospective, Randomized, Pilot Study of Outcomes for Digital Nerve Repair in the Hand Using Hollow Conduit Compared With Processed Allograft Nerve.

Current repair options for peripheral nerve injuries where tension-free gap closure is not possible include allograft, processed nerve allograft, and hollow tube conduit. Here we report on the outcomes from a multicenter prospective, randomized, patient- and evaluator-blinded, pilot study comparing processed nerve allograft and hollow conduit for digital nerve reconstructions in the hand. Across 4 centers, consented participants meeting inclusion criteria while not meeting exclusion criteria were randomized intraoperatively to either processed nerve allograft or hollow conduit. Standard sensory and safety assessments were conducted at baseline, 1, 3, 6, 9, and 12 months after reconstruction. The primary outcome was static 2-point discrimination (s2PD) testing. Participants and assessors were blinded to treatment. The contralateral digit served as the control. We randomized 23 participants with 31 digital nerve injuries. Sixteen participants with 20 repairs had at least 6 months of follow-up while 12-month follow-up was available for 15 repairs. There were no significant differences in participant and baseline characteristics between treatment groups. The predominant nerve injury was laceration/sharp transection. The mean ± SD length of the nerve gap prior to repair was 12 ± 4 mm (5-20 mm) for both groups. The average s2PD for processed allograft was 5 ± 1 mm (n = 6) compared with 8 ± 5 mm (n = 9) for hollow conduits. The average moving 2PD for processed allograft was 5 ± 1 mm compared with 7 ± 5 mm for hollow conduits. All injuries randomized to processed nerve allograft returned some degree of s2PD as compared with 75% of the repairs in the conduit group. Two hollow conduits and one allograft were lost due to infection during the study. In this pilot study, patients whose digital nerve reconstructions were performed with processed nerve allografts had significantly improved and more consistent functional sensory outcomes compared with hollow conduits.

Motorcycle Accident Profile in Manipal Teaching Hospital

This is a prospective descriptive study conducted at Manipal Teaching Hospital (MTH), where 140 patients seen at Emergency Room and OPD with a history of motorcycle accident from May 2015 to August 2015 were studied. Results showed that a high percentage of males 121 (86.4%) were involved in motorcycle accidents. Peak age range was 31-40 years old (61) (43.5%). Most of the motorcycles were manufactured in India (118) (84.2%). Single rider type of motorcycle accounted for 32(22.8%) of cases with a average speed of 50-70 km/hr (76.4%). The driver of the motorcycle was significantly involved in 106(75.7%) of cases. Alcohol intake was found in 40(28.6%) and non-license holder was 22 (15.7%) among accident victims. Abrasions 92(65.7%) was the predominant injury sustained followed by fractures 28(20%), lacerations 15(10.7%), and hematoma 10 (7.1%) in isolation or in combination. Combination of pain relievers128(91.4%), antibiotics 95(67.8%), suturing 18(12.8%), antitetanus 107(76.4%) and fracture management 21(15%) were the mode of management for these accidents. Most patients seen were discharged 116(82.8%) with home medications, wound care and follow-up, and only 24(17.2%) were admitted for observation and specific medical and surgical management.

Risk Factors for Fall-Related Injuries Leading to Hospitalization Among Community-Dwelling Older Persons: A Hospital-Based Case-Control Study in Thiruvananthapuram, Kerala, India.

This study intended to identify the risk factors for injurious falls that led to hospitalization of older persons living in the community. A hospital-based unmatched incident case-control study was done among 251 cases and 250 controls admitted at a tertiary care centre in Kerala. Mean age of cases was 71.6 ± 9.13 years and that of controls was 67.02 ± 6.17 years. Hip fractures were the predominant injury following falls. Falls were mostly a result of intrinsic causes. After adjusting for other variabes, the risk factors for all injuries were age above 70 years (odds ratio [OR] = 2.25; 95% confidence interval [CI] = 1.46-3.46), previous fall history (OR = 2.76; 95% CI = 1.08-7.08), impaired vision (OR = 4.49; 95% CI = 2.77-7.30), not living with spouse (OR = 1.97; 95% CI = 1.31-2.97), door thresholds (OR = 1.52; 95% CI = 1.01-2.29), and slippery floor (OR = 2.37; 95% CI = 1.31-4.32). The risk factors for hip fractures and other injuries were identified separately. Fall prevention strategies among older persons are warranted in Kerala.

Is There Evidence to Support the Use of the Angle of Peak Torque as a Marker of Hamstring Injury and Re-Injury Risk?

Hamstring strain injuries are the predominant injury in many sports, costing athletes and clubs a significant financial and performance burden; therefore, the ability to identify and intervene with individuals who are considered at high risk of injury is important. One measure that has grown in popularity as an outcome variable following hamstring intervention/prevention studies and rehabilitation is the angle of peak knee flexor torque. This current opinion article will firstly introduce the measure and the processes behind it. Second, the article will summarise how the angle of peak knee flexor torque has been suggested to measure hamstring strain injury risk. Finally, the numerous limitations will be presented and the article will outline how these limitations may influence the usefulness of the angle of peak knee flexor torque measure. These include the lack of muscle specificity, the common concentric contraction mode of assessment, reliability of the measure, various neural contributions (such as rate of force development and neuromuscular inhibition), as well as the lack of prospective data showing any predictive value in the measure.

Volar Plate Avulsion of Pip Joint: An Unusual Fielding Injury in Cricket

ABSTRACT Fielding injuries are the predominant contact injury in cricket, with the fingers taking the blunt of the trauma due to direct hit by the ball while taking catches. Many types of hand and finger injuries like soft tissue contusions, fractures/dislocations and ligament and joint sprains have been observed in this popular team sport. One of the unique kind of hand injuries associated with cricket is the avulsion of the volar plate of the proximal interphalangeal joint (PIP). Here, we report this unusual injury in a 24-year-old cricketer, its management and 3-month follow-up along with a review of hand injuries in cricket. How to cite this article Prabhakar S, Dhillon HS, Syam K, Dhillon SS, Dhillon MS. Volar Plate Avulsion of Pip Joint; An Unusual Fielding Injury in Cricket. J Postgrad Med Edu Res 2015;49(4):209-212.

The Mechanics of Injury Production and Wounding Forces in Judicial Context

An injury is defined as illegally caused harm to any person’s body, mind reputation or property. In practice, injuries often consist of combination of several basic injury types and usually classified according the predominant injury type. The wounding process and distribution of injuring force are governed by equations of motion physics. However, the purpose Legal judgment demands the forensic medical expert, as an independent witness, to explain those complex biophysical remedies in the context of the common legal sense, which can be easily understood by the courts. Therefore, we suggest the following simple biomechanical classification of wounding process that could serve the purpose; light force, moderately heavy force and heavy force injuries.

In vivo detection of nerve injury in familial amyloid polyneuropathy by magnetic resonance neurography.

Transthyretin familial amyloid polyneuropathy is a rare, autosomal-dominant inherited multisystem disorder usually manifesting with a rapidly progressive, axonal, distally-symmetric polyneuropathy. The detection of nerve injury by nerve conduction studies is limited, due to preferential involvement of small-fibres in early stages. We investigated whether lower limb nerve-injury can be detected, localized and quantified in vivo by high-resolution magnetic resonance neurography. We prospectively included 20 patients (12 male and eight female patients, mean age 47.9 years, range 26-66) with confirmed mutation in the transthyretin gene: 13 with symptomatic polyneuropathy and seven asymptomatic gene carriers. A large age- and sex-matched cohort of healthy volunteers served as controls (20 male and 20 female, mean age 48.1 years, range 30-73). All patients received detailed neurological and electrophysiological examinations and were scored using the Neuropathy Impairment Score-Lower Limbs, Neuropathy Deficit and Neuropathy Symptom Score. Magnetic resonance neurography (3 T) was performed with large longitudinal coverage from proximal thigh to ankle-level and separately for each leg (140 axial slices/leg) by using axial T2-weighted (repetition time/echo time = 5970/55 ms) and dual echo (repetition time 5210 ms, echo times 12 and 73 ms) turbo spin echo 2D sequences with spectral fat saturation. A 3D T2-weighted inversion-recovery sequence (repetition time/echo time 3000/202 ms) was acquired for imaging of the spinal nerves and lumbar plexus (50 axial slice reformations). Precise manual segmentation of the spinal/sciatic/tibial/common peroneal nerves was performed on each slice. Histogram-based normalization of nerve-voxel signal intensities was performed using the age- and sex-matched control group as normative reference. Nerve-voxels were subsequently classified as lesion-voxels if a threshold of >1.2 (normalized signal-intensity) was exceeded. At distal thigh level, where a predominant nerve-lesion-voxel burden was observed, signal quantification was performed by calculating proton spin density and T2-relaxation time as microstructural markers of nerve tissue integrity. The total number of nerve-lesion voxels (cumulated from proximal-to-distal) was significantly higher in symptomatic patients (20 405 ± 1586) versus asymptomatic gene carriers (12 294 ± 3199; P = 0.036) and versus controls (6536 ± 467; P < 0.0001). It was also higher in asymptomatic carriers compared to controls (P = 0.043). The number of nerve-lesion voxels was significantly higher at thigh level compared to more distal levels (lower leg/ankle) of the lower extremities (f-value = 279.22, P < 0.0001). Further signal-quantification at this proximal site (thigh level) revealed a significant increase of proton-density (P < 0.0001) and T2-relaxation-time (P = 0.0011) in symptomatic patients, whereas asymptomatic gene-carriers presented with a significant increase of proton-density only. Lower limb nerve injury could be detected and quantified in vivo on microstructural level by magnetic resonance neurography in symptomatic familial amyloid polyneuropathy, and also in yet asymptomatic gene carriers, in whom imaging detection precedes clinical and electrophysiological manifestation. Although symptoms start and prevail distally, the focus of predominant nerve injury and injury progression was found proximally at thigh level with strong and unambiguous lesion-contrast. Imaging of proximal nerve lesions, which are difficult to detect by nerve conduction studies, may have future implications also for other distally-symmetric polyneuropathies.

Choice of a nonsteroidal anti-inflammatory drug in ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic systemic disease with predominant axial skeleton injury, peripheral articular and entheseal involvements, and extra-skeletal manifestations. 8–10 years elapse since the first manifestations of AC to its diagnosis, leading to delays in adequate therapy, to the progression of structural and functional impairments in the axial skeleton and peripheral joints and to the development of complications. According to the international and Russia's Association of Rheumatologists guidelines, nonsteroidal anti-inflammatory drugs (NSAIDs) are an important component of AS therapy. It is necessary to carefully choose the safest NSAID for these patients, by taking into consideration that AS therapy should be long-term and continuous. The trial previously performed by the authors evaluated comorbidity in 220 AS patients long receiving nimesulide. Its long-term administration was shown to cause no increase in the level of liver enzymes. Esophagogastroduodenoscopy revealed antral gastritis in 23.6% of the patients, gastric mucosal erosions in 13, and gastric ulcer disease without an exacerbation in 3.6%. It was noted that the physicians had not prescribed gastroprotectors to the patients. Nimesulide caused no blood pressure (BP) elevation even in patients who had baseline hypertension. Elevated BP occurred in 2.5% of the patients. There was no clear association of higher BP with nimesulide intake since the patients had previously used other NSAIDs, mainly diclofenac, to treat severe pain syndrome. These findings suggest that in addition to its analgesic activity, nimesulide shows good tolerability in patients with AS, which permits its long-term use, but in this case the gastrointestinal tract and BD should be carefully monitored, which will be able to prevent the possible adverse events characteristic of the entire group of NSAIDs.

Incidence, mechanism and risk factors for injury in youth rock climbers

BackgroundRock-climbing participation has grown globally in recent years, and the sport was officially recognised by the International Olympic Committee in 2010. The epidemiology of climbing injuries in adults has been...

Pedestrian Injuries in the Most Densely Populated City in Nigeria—An Epidemic Calling for Control

Objectives: Since the first pedestrian road fatality of 1896, pedestrians still remain vulnerable, with fatalities in Africa being 55% of global statistics. Many previous reports from Nigeria have emphasized passengers and drivers over pedestrians; this study was done in the most densely populated Nigerian city with no previous publication exclusively dedicated to pedestrians—the megacity has been projected by the World Bank to be the third largest in the world by 2015 (after Tokyo and Mumbai), so the study results would aid injury control and reduce morbidity and mortality.Methods: This is a one-year prospective study on pedestrians attending the surgical emergency room of the busiest referral hospital in Lagos, Nigeria, detailing age, sex, occupation, regions injured, injury mechanism, incident vehicles, highway collisions, and immediate outcomes.Results: Some 702 pedestrians were seen, including 494 (70%) males with overall peak incidence in the third decade, but the peak incidence among females is lower and in the first decade. Common injuries sustained were to the head (40%), lower limbs (35%), upper limbs (9%), multiple regions (6%), pelvis (3%), and others (7%). Gender differences also were noted—the predominant injury location in males was the head, followed by lower limbs; the opposite was true for females, though both regional injuries were fewer in females than in males. Students were 20% of the entire pedestrians, with nearly half of them injured by a motorcycle. The mechanism of injury included crossing a highway (63%), walking along the pavement (17%), standing by a bus stop (12%), at a shop/house (5%), and others (3%). However, 76% injuries occurred on highways, 22% on inner city roads, and 2% elsewhere. Vehicles included motorcycles (33%), cars (27%), buses (22%), trucks (6%), tricycles (2.4%), and other (9%). Overall fatality was 10% and about half were due to being knocked down by buses and cars.Conclusions: This study suggests a high incidence and significant underreporting of pedestrian injuries. A reduction in morbidity and mortality is possible (from head and lower limb injuries) by traffic calming techniques in crossing the highway, especially injuries due to being struck by motorcycles, cars, and buses.

Novel protocol including liver biopsy to identify and treat CD8+ T-cell predominant acute hepatitis and liver failure.

In the majority of children with ALF, the etiology is unknown and liver transplantation is often needed for survival. A patient case prompted us to consider that immune dysregulation may be the cause of indeterminate acute hepatitis and liver failure in children. Our study includes nine pediatric patients treated under a multidisciplinary clinical protocol to identify and treat immune-mediated acute liver injury. Patients with evidence of inflammation and no active infection on biopsy received treatment with intravenous immune globulin and methylprednisolone. Seven patients had at least one positive immune marker before or after treatment. All patients had a CD8+ T-cell predominant liver injury that completely or partially responded to immune therapy. Five of the nine patients recovered liver function and did not require liver transplantation. Three of these patients subsequently developed bone marrow failure and were treated with either immunosuppression or stem cell transplant. This series highlights the importance of this tissue-based approach to diagnosis and treatment that may improve transplant-free survival. Further research is necessary to better characterize the immune injury and to predict the subset of patients at risk for bone marrow failure who may benefit from earlier and stronger immunosuppressive therapy.

Maternal or neonatal infection: association with neonatal encephalopathy outcomes

BackgroundPerinatal infection may potentiate brain injury among children born preterm. The objective of this study was to examine whether maternal and/or neonatal infection are associated with adverse outcomes among term neonates with encephalopathy.MethodsCohort study of 258 term newborns with encephalopathy whose clinical records were examined for signs of maternal infection (chorioamnionitis) and infant infection (sepsis). Multivariate regression was used to assess associations between infection, pattern and severity of injury on neonatal MRI, as well as neurodevelopment at 30 months (neuromotor exam, or Bayley Scales of Infant Development II MDI <70 or Bayley III cognitive score <85).ResultsChorioamnionitis was associated with lower risk of moderate-severe brain injury (adjusted OR 0.3; 95% CI 0.1–0.7, P=0.004), and adverse cognitive outcome in children when compared to no chorioamnionitis. Children with signs of neonatal sepsis were more likely to exhibit watershed predominant injury than those without (P=0.007).ConclusionsAmong neonates with encephalopathy, chorioamnionitis was associated with a lower risk of brain injury and adverse outcomes, whereas signs of neonatal sepsis carried an elevated risk. The etiology of encephalopathy and timing of infection and its associated inflammatory response may influence whether infection potentiates or mitigates injury in term newborns.

Lung Metabolism During Ventilator-Induced Lung Injury

Concerns about pulmonary complications of positive pressure ventilation (1) are at least as old as the description of the Acute Respiratory Distress Syndrome (ARDS) (2). Yet, it took about a decade until experimental findings (3) shifted the focus from air leaks and oxygen toxicity to the biological effects of large excursions of the lung parenchyma (4). The demonstration that mechanical ventilation with high peak inspiratory pressures and low positive end-expiratory pressure (PEEP) could produce edema, increased alveolo-capillary permeability, leukocyte infiltration, and inflammation in normal lungs established the current understanding of ventilator-induced lung injury (VILI) (4, 5). The clinical relevance of VILI was confirmed by the demonstration of a 22% decrease in mortality of ARDS patients when lung stretch was reduced through lower tidal volumes (VT). (6). In addition to excessive lung stretch due to large VT, it has been recognized that VILI can also be caused by low end-expiratory lung volumes, even at low airway pressures. Mechanisms proposed to explain such injury include concentration of stresses in the heterogeneously expanding lung parenchyma (7), and propagation and rupture of liquid plugs producing injurious fluid mechanical stresses during cyclic recruitment-derecruitment of distal lung units (8, 9). Mitigation of these low-volume phenomena by optimizing lung recruitment with higher PEEP levels (10) and proning (11) has been beneficial in patients with moderate and severe ARDS. However, despite the large number of experimental and clinical studies, uncertainty persists about the relative contribution of overdistension versus low-volume injury to the ultimate lung damage produced by VILI (12). Topographically, in supine patients, nondependent (ventral) injury would be expected if overdistension would predominate (13), whereas dependent (dorsal) damage would be expected for predominant low-volume injury (14). The clinical relevance of the topic has been emphasized by the suggestion that the mass of opening-closing lung is an independent risk factor for death in patients with ARDS (15), and that regional forces during mechanical ventilation determine lung parenchyma abnormalities found in ARDS survivors (16).

Unmyelinated axon loss with postnatal hypertonia after fetal hypoxia.

White matter (WM) injury due to myelination defects is believed to be responsible for the motor deficits seen in cerebral palsy. We tested the hypothesis that the predominant injury is to functional electrical connectivity in unmyelinated WM fibers by conducting a longitudinal study of central WM tracts in newborn rabbit kits with hypertonia in our model of cerebral palsy. Pregnant rabbits at 70% gestation underwent 40-minute uterine ischemia. Motor deficits in newborn kits, including muscle hypertonia, were assessed by neurobehavioral testing. Major central WM tracts, including internal capsule, corpus callosum, anterior commissure, and fimbria hippocampi, were investigated for structural and functional injury using diffusion tensor magnetic resonance imaging (MRI), electrophysiological recordings of fiber conductivity in perfused brain slices, electron microscopy, and immunohistochemistry of oligodendrocyte lineage. Motor deficits were observed on postnatal day 1 (P1) when WM tracts were unmyelinated. Myelination occurred later and was obvious by P18. Hypertonia was associated with microstructural WM injury and unmyelinated axon loss at P1, diagnosed by diffusion tensor MRI and electron microscopy. Axonal conductivity from electrophysiological recordings in hypertonic P18 kits decreased only in unmyelinated fibers, despite a loss in both myelinated and unmyelinated axons. Motor deficits in cerebral palsy were associated with loss of unmyelinated WM tracts. The contribution of injury to myelinated fibers that was observed at P18 is probably a secondary etiological factor in the motor and sensory deficits in the rabbit model of cerebral palsy.