*Case Report* **Traumatic Hip Dislocation in Pediatric Patients: Clinical Case Series and a Narrative Review of the Literature with an Emphasis on Primary and Long-Term Complications**

**Eetu N. Suominen and Antti J. Saarinen \***

Department of Orthopedics and Traumatology, Helsinki University Hospital, 00260 Helsinki, Finland **\*** Correspondence<EMAIL_ADDRESS>
**Abstract:** Traumatic hip dislocation is a rare injury in pediatric populations. Dislocation may be associated with low-energy trauma, such as a minor fall. Traumatic hip dislocation is associated with severe complications, such as avascular necrosis of the femoral head. Timely diagnosis and reposition decrease the rate of complications. In this study we retrospectively assessed traumatic hip dislocations in pediatric patients during a 10-year timespan in a university hospital. There were eight cases of traumatic hip dislocations. All patients had a minimum follow-up of two years and were followed with MRI scans. One patient developed avascular necrosis during the follow-up which resolved conservatively. There were no other significant complications. In conclusion, traumatic hip dislocation is a rare injury which is associated with severe complications. Patients in our case series underwent a timely reposition. The complication rate was similar to previous reports.

**Keywords:** hip dislocation; pediatric trauma; pediatric injury; avascular necrosis

**Citation:** Suominen, E.N.; Saarinen, A.J. Traumatic Hip Dislocation in Pediatric Patients: Clinical Case Series and a Narrative Review of the Literature with an Emphasis on Primary and Long-Term Complications. *Children* **2023**, *10*, 107. https://doi.org/10.3390/ children10010107

Academic Editors: Axel A. Horsch, Maher A. Ghandour and Matthias Christoph M. Klotz

Received: 18 October 2022 Revised: 14 November 2022 Accepted: 16 November 2022 Published: 4 January 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

### **1. Introduction**

Traumatic hip dislocation is a rare injury among the pediatric population. Patients over 10 years of age typically require a major traumatic event for dislocation [1]. However, in younger children the dislocation may occur from a minor trauma as the traumatic energy required for hip dislocation increases with age [2–4]. Posterior dislocation is the most common type of injury, making up approximately 95% of traumatic dislocations [2]. Typical characteristics of posterior dislocation are adduction, flexion, internal rotation, and shortening of the dislocated limb [5]. Associated injuries increase with age and higher energy trauma. Associated acetabular and femoral fractures are uncommon in pediatric patients.

Closed reduction under moderate conscious anesthesia can be used in adolescent patients. Reduction is usually easy to achieve, but interfering fragments originating from the hip joint structures may prevent concentric reduction. In young children, a closed reduction in an operating room with readiness to convert to open reduction is recommendable [5]. If the operating room is unavailable, closed reduction should be performed in the emergency department. The successful reduction should be confirmed using fluoroscopy [6]. Widening of the injured joint space indicates unsuccessful reduction. If a congruent and stable hip joint is not achieved using the closed reduction, an open reduction is needed. After successful reduction, immobilization with a hip spica cast is recommended for children under 10 years. Protected weight bearing for 6–8 weeks is recommended for older patients [3].

Avascular necrosis (AVN) is the feared complication of hip dislocation. The only statistically proven risk factor is delay between dislocation and reduction. If the delay is greater than 6 h, the risk of avascular necrosis is increased 20-fold [2,3,6]. Reduction may happen spontaneously, especially in young children [3]. Magnetic resonance imaging (MRI) during the primary care is warranted for patients with suspected spontaneously reduction or with signs of unsuccessful reduction to assess soft tissue entrapments not visible on

radiographs [7]. As AVN may develop up to two years after the injury, follow-up clinical surveillance and control MRIs are warranted.

In this study, we describe a patient series from a tertiary university hospital during a ten-year period. We also present a narrative literature review with an emphasis on primary complications and complications during extended follow-up after traumatic hip dislocation in pediatric patients.

#### **2. Materials and Methods**

Institutional review board permission was obtained for the study. A consecutive case series of acute, traumatic hip dislocations in skeletally immature patients between 1 January 2009 and 31 December 2019 treated in the pediatric orthopedic department of Turku University Hospital, Finland were reviewed retrospectively. A retrospective cohort of patients was collected using the International Classification of Diseases (ICD) code for hip dislocation (S73) to identify the cases from the patient charts of our center. Inclusion criteria were the correct diagnosis of traumatic hip dislocation, skeletally immaturity, minimum of two years of follow-up, and adequate clinical and radiographic information. Non-traumatic dislocations were excluded from the study. No patients with traumatic dislocations were excluded.

Patient characteristics and the etiology of the injury were collected from the patient charts. Approximate time from injury to reduction was assessed. Associated injuries and successful reduction were assessed from radiographs. MRIs taken during the follow-up were evaluated. Complications were assessed during the follow-up. The mechanism of injury was defined as high energy if it was because of a motor-vehicle accident or a fall from a height of more than 3 m (10 feet). A low-energy injury was defined as a typical play activity or fall from a height of less than 3 m (10 feet) [8].

#### **3. Results**

During the study period, eight patients treated for traumatic hip dislocation were identified. Four patients were male and four female. The mean age at the time of the injury was 11.7 years (range from 4.4 to 16 years). Three patients had a dislocation after a low energy trauma. Two of these patients were aged four years, and one patient was seven years at the time of the accident. Five patients had a hip dislocation after a high energy trauma. These patients were 14 to 16 years old. Six patients had posterior and two had anterior dislocations. The detailed descriptions of the patients and accidents are presented in Table 1.

Three patients over 10-years old had associated fractures. One patient had a Hill– Sachs lesion of the femoral head with loose extra-articular osteochondral fragment at the caput–collum border. This patient had an anterior dislocation of the femoral head. Two patients had acetabulum fractures as an associated injury. In one of these patients, an MRI showed a posterocranial fracture of the acetabulum with a 7 mm lateral dislocation between acetabulum and ramus. In another patient, a caudal acetabulum fracture was observed with a 25 mm × 13 mm sized dislocated fragment. These fractures were treated conservatively. None of the patients developed complications during the follow-up. There were no recurrent dislocations.

The mean time to reduction was approximately 3 h (range from 2 to 5 h). During the follow-ups, there were no radiological or clinical evidence of growth disturbances, heterotrophic ossification, early epiphysis closure, or post-traumatic arthritis. None of the patients had abnormal neurological or vascular findings in the lower extremity. None of the patients required surgical intervention for reduction or associated injuries.

The mean duration of the follow-up was 7.9 years (range from 4.1 to 9.8 years). One patient presented with bone edema and flattening of the caput indicating AVN at 4 weeks after the injury (Patient 7 in Table 1). Time to successful reduction in this patient was five hours. The patient was treated conservatively with a 6-month weight bearing prohibition. AVN was resolved at 6 months MRI control and the patient was asymptomatic in the clinical examination.

**Table 1.** Clinical characteristics and etiology of the injuries.

#### **4. Discussion**

Several studies in recent history have studied the epidemiology, mechanism of injury, clinical presentation, diagnosis, and treatment of the traumatic hip dislocation in a pediatric population. The findings of our study are consistent with the results of the previous research. Traumatic hip dislocation in the pediatric population is an uncommon injury that requires timely diagnosis and intervention. Due to low traumatic energy or untypical etiology, pediatric hip dislocation may go unnoticed [9,10]. Special caution is needed with unconscious patients in whom the ambulatory status is unknown.

Traumatic posterior hip dislocation in children often presents with the classic lower limb deformity. The hip is in flexion, adduction, and internal rotation. The involved limb appears shorter than the contralateral limb and the femoral head can be palpated posteriorly. Radiographs should be obtained without delay after adequate pain medication. The presence of another fracture or injury can divert attention from hip dislocation and delay the diagnosis. The dislocation of the femoral head can be anterior or posterior. Similar to adult patients, the majority of hip dislocations are posterior [11]. Bilateral dislocations have been reported in the literature but are exceptional [12]. A prompt closed reduction with the patient under suitable anesthesia and analgesia is considered to be appropriate treatment. Closed reduction is usually accomplished via traction in line with the deformity. In cases in which the diagnosis of hip dislocation is delayed, some studies suggest a short period of skeletal traction after the successful reduction until pain is improved. However, the advantage of this in order to achieve easier reduction has been compromised [10].

The traumatic energy required for a traumatic hip dislocation increases with age [1,5,6]. This was also seen in our patient sample as patients younger than 10 years had minor traumatic events in contrast to adolescents, who all had high-energy trauma. When compared to adult patients, associated fractures are rare in pediatric patients after traumatic hip dislocation. Large posterior wall fractures or fractures with articular surface dislocation require internal fixation to prevent hip instability.

Radiographic assessment by anteroposterior, oblique, and lateral imaging of the pelvis is crucial before and after reduction. Plain radiographs and CT scans may not adequately show acetabulum fractures in young children due to unossified bone. In these patients an MRI is warranted [7,13,14]. MRIs also provides information on soft-tissue injuries, including labral and capsular tears along with cartilage and muscular injuries [7]. Widening of the articular space in radiographs can be caused by entrapment of soft-tissue and requires imaging with an MRI. Archer et al. reported a patient with unrecognized physeal injury in whom the attempted closed reduction resulted in a hip fracture requiring open reduction and internal fixation [5]. When any uncertainties exist regarding hip joint congruency, a CT or MRI scan should be performed to identify intra-articular bone fragments or interposed soft tissue. Concerning the additional injuries connected with traumatic hip dislocation in pediatric patients, an acetabular fracture can be underestimated with radiographs and CT scans [13].

In our patients, no severe complications occurred during the follow-up. One 4.6-yearold patient presented with AVN after a posterior dislocation after landing with the hip on abduction and flexion on a bouncing castle. Dislocation was reduced after approximately five hours from the injury with a closed reposition in the operating room after which the patient was fitted with a spica cast. AVN was discovered in a routine MRI scan at four weeks after the injury. After the imaging finding, the patient was assigned to non-weight bearing for six months. AVN resolved during the follow-up at six months and patient returned to normal activities without difficulties.

Reduction in the dislocated joint restores the normal blood flow to the femoral head. The risk of osteonecrosis is substantial and may occur in up to one-third of dislocations, depending on the severity of injury. AVN of the femoral head is the most feared and frequent serious complication related to traumatic hip dislocation. Symptoms of AVN include painless limp, pain, and restricted movement. The incidence of AVN in children younger than 18 years is reported to be 3% to 15% after an isolated hip dislocation [15,16]. AVN is caused when the arterial perforation is disturbed. Precise pathological process of the AVN remains unclear. In a cadaver study, Chung demonstrated incomplete anastomotic and transepiphyseal vessels in skeletally immature patients [17]. Undeveloped anastomotic perforation exposes the femoral head to ischemia during the dislocation [2,17]. AVN may lead to severe disability and need for a hip replacement. Evidence at present indicates an association between late hip reduction and higher rate of osteonecrosis of the femoral head in all traumatic hip dislocations [18]. Hence, all traumatic hip dislocations should be reduced as soon as possible to decrease the rate of osteonecrosis of the femoral head. When a traumatic hip dislocation is associated with femoral epiphysiolysis, the risk increases to 100% [19,20]. Because of the risk of AVN, patients should be routinely followed with MRI scans. In our study, timely reduction was achieved in all the patients and the patients were adequately followed after the dislocation.

Primary neurologic complications associated with pediatric hip dislocations are rare, presumably due to the low traumatic energy typical to these injuries. The peroneal branch of the sciatic nerve is the most likely peripheral nerve to be injured. Sciatic nerve injuries are reported in the literature with an incidence rate of approximately 5% [21]. Nerve injuries associated with traumatic hip dislocations are usually a neurapraxias and symptoms are most often transitory. The peroneal nerves are most commonly affected. Pre- and postreductive neurovascular status should always be examined. In our patient series, no neurologic complications occurred. Other uncommon complications of the traumatic hip dislocation in pediatric patients include recurrent dislocation, heterotrophic ossification, and development of coxa magna. Recurrent dislocation may be associated with a defect in the capsule or attenuation of the hip capsule without a tear. Acute redislocation, which occurs soon after reduction, implies that the reduction was not congruent and additional investigation with a CT scan is indicated with probable open exploration [11]. Proximal femoral head displacement (epiphyseolysis) during reduction in hip dislocation has been

reported in the literature [19]. The possibility of physeal fracture should be kept in mind in traumatic hip dislocation occurring in children and adolescents with an open physis.

The development of the complications in traumatic hip dislocation can be delayed several years. Older studies before follow-up with MRIs have reported avascular necrosis after three years of the injury [22]. Patients should be subjected to long-term follow-up.

Neglected or untreated traumatic hip dislocations are rare. There are few reports on neglected traumatic dislocation. Although previous studies and case reports have presented a wide variety of treatment, the optimal management remains unclear. At a time-interval between injury and reduction procedure beyond 3–4 weeks, a reductional operation should be performed [16,23]. Even if the open reduction is delayed, it may prevent deformity, and will maintain the length of the lower extremity [24]. Regarding the surgical technique, it has been proposed that the surgeon should release the adductor longus, lengthen the psoas tendon, and insert a K-wire [16]. As mentioned, the traumatic hip dislocation in children is, in majority of the patients, an isolated injury, without a concurrent acetabular fracture. Therefore, the surgical technique should be chosen so that the operation does not further compromise the articular cartilage or the vascular structures of the femoral head.

No study to date has been able to define the type of rest required or the length of time for which it should be applied and there is no evidence that this affects the long-term outcome. Early gentle range of motion and patient mobilization should be instituted. Under the age of 10 years, immobilization with a spica cast for 4 weeks, along with suitable rehabilitation is particularly important for the healing of surrounding soft tissues to make the joint become stable [1]. Yuksel et al. suggest that the non-weight bearing interval of 4 weeks and partial weight bearing after 6 weeks are appropriate periods to let the soft tissue heal [6]. According to Sahin et al., neither the type of the treatment (post-reduction traction or bed rest) nor the time from injury to full-weight bearing influenced outcomes significantly [25].

The small sample size of our patient series prevented us from performing statistical analyses. Most prior reports on traumatic hip dislocations in pediatric patients are case reports or small case series. We report a modern single center case series with extensive follow-up with routinely taken MRI scans.

#### **5. Conclusions**

Traumatic hip dislocation is a rare injury in pediatric patients and is often associated with low-energy trauma. Adequate diagnosis and repositioning prevent complications, such as avascular necrosis of the femoral head. Radiographs should be obtained when a pediatric patient is unambulatory after a traumatic event, such as a fall. A shortened leg held in adduction and internal rotation should prompt the emergency physician to consider ordering radiographs and provide analgesia for the child. Primary MRI scans might be warranted to exclude associated injuries. During follow-up, MRI scans should be routinely taken to rule out avascular necrosis. The possibility of other associated injuries should be taken into account, especially in the patients with high-energy trauma. With appropriate management, most children with traumatic hip dislocation treated promptly with closed reduction will have an excellent outcome.

**Author Contributions:** Conceptualization, E.N.S. and A.J.S.; methodology, E.N.S. and A.J.S.; investigation, E.N.S. and A.J.S.; resources, E.N.S. and A.J.S.; data curation, E.N.S. and A.J.S.; writing—original draft preparation, E.N.S.; writing—review and editing, A.J.S.; supervision, A.J.S.; funding acquisition, E.N.S. and A.J.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by The Päivikki and Sakari Sohlberg Foundation, University of Turku, and Clinical Research Institute HUCH.

**Institutional Review Board Statement:** The study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board of University of Turku.

**Informed Consent Statement:** Patient consent was waived due to the retrospective setting.

**Data Availability Statement:** Study data can be obtained from the corresponding author for a reasonable request.

**Acknowledgments:** Open Access funding provided by the University of Helsinki.

**Conflicts of Interest:** The authors declare no conflict of interests.

### **References**

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*4.5. Robustness Tests*

To further validate the results and test their consistency, several robustness checks were performed. Our robustness test mainly relates to three concerns. Firstly, one concern exists about the appropriateness of a proxy for R&D investment intensity. Referring to the method of Kao and Chen (2020) [111], we firstly substitute the R&D investment intensity with the proportion of R&D expenses in total assets (See Table 7). Secondly, another concern involves how existing extreme observations may influence the accuracy of our estimations. Therefore, all continuous variables are once again winsorized by 5% instead of 1% (See Table 8). Thirdly, the last concern relates to improper designation for the omitted dependent variable. Considering the incompleteness of data, some firms' R&D investments maybe not be disclosed and are treated as omitted observations. For a large number of omitted observations, we cannot distinguish between zeros that represent a true zero level of R&D activity and zeros that were created by the statistical authorities because no figures were recorded in the database. During the previous empirical process, these omitted observations are made to be zero. However, this designation may lead to an underestimation of coefficients. Therefore, we exclude these samples and carry out the regressions again (See Table 9). Overall the results were highly robust to these changes in specification.

**Table 7.** Variable Replacement test.

**Notes:** Standard errors are in parentheses. \*\*\* *p* < 0.01, \*\* *p* < 0.05, \* *p* < 0.1

Additionally, we address endogeneity issues in our analysis by applying an instrumental variable approach. Specifically, we analyze whether our mediator variable is exogenous in model (3). A recent contribution proposes that firm innovation inversely increases the firm information environment overall, subsequently stimulating firms' access to financing [112]. There may exist a problem of mutual cause and effect between firm overborrowing and the R&D investment intensity. In addition, the Hausman test [113] for endogeneity also shows that there exists endogeneity in overborrowing. To alleviate the endogeneity problem, we carry out the 2SLS regression test [114]. We take the mean of industrial overborrowing as the instrument variable of a firm's overborrowing. It is correlated with the firm's overborrowing, whereas it is unlikely to be affected by the firm's R&D investment intensity, thus meeting the basic requirements of correlation and exogeneity of instrument variables. The under-identification test (Anderson LM statistic is 903.83, *p* value is 0.00) also reflects that the instrument variable is correlated with the endogenous variable. The weak ID test statistics (Cragg–Donald Wald F is 1075.54) are far beyond the 10% Stock–Yogo weak critical values of 16.38, further rejecting that the instrument is weak. Our results in Table 10 show that the mediator—overborrowing—does cause firm's R&D intensity to drop down significantly.

**Table 8.** Winsorize Test (5%).

**Notes:** Standard errors are in parentheses. \*\*\* *p* < 0.01, \*\* *p* < 0.05, \* *p* < 0.1.

**Table 9.** Eliminating the default sample of R&D investment intensity.

**Notes:** Standard errors are in parentheses. \*\*\* *p* < 0.01, \*\* *p* < 0.05, \* *p* < 0.1.

**Table 10.** 2 SLS Regression Results.

**Notes:** Standard errors in parentheses. \*\*\* *p* < 0.01, \* *p* < 0.1.


*4.1. General Trends*

Recent technological developments have made wearable inertial sensors readily available. This has led to sport coaches integrating these devices into their training routines to obtain more measures of an athlete's sport performance in real time [48]. This review highlighted three major research disciplines that are implementing inertial sensors into a rowing setting. These are Biomechanics (*n* = 3), Sport Science and Medicine (*n* = 5), and Engineering and Technology (*n* = 28). The increased availability of inertial sensors is reflected by the rapid increase in the volume of research investigating the use of inertial sensors in rowing since 2004 (Figure 2b). There is a diverse geographic spread of rowing technology research. Countries such as Algeria, Australia, Canada, China, France, Germany, Greece, Italy, Malaysia, Netherlands, New Zealand, Portugal, Slovenia, Spain, Sweden, Switzerland, the United Kingdom, and the United States of America all reported the use of inertial sensors in rowing. The majority of research published originated from Italy (16.7%). Italy won six gold medals at the U23 world championships that may demonstrate the value of integrating sport technology into athlete training programs [49].


**2. Theoretical background**

Internet has made a vast range of activities accessible to a huge number of individuals. In contrast to other types of social exchange, the internet is quick, efficient, and direct, so that minimal efforts are required to accomplish goals. DC is thus important for conveying information and increasing contact with stakeholders. Even though computer-mediated

contact lacks the social and physical clues that are essential for good communication, individuals prefer to use DC as a medium with a social presence commensurate with the task they wish to accomplish (Hollingshead & Noshir, 2002), whether for employment, leisure, to broaden personal horizons, or for attaining social status (Cnaan, Handy & Wadsworth, 1996). These assumptions are at the core of the "functional" approach to DC that covers a wide range of aspects such as selective processing, channel complementation etc. (Dutta & Bodie, 2008). The common factor underlying this functional approach is "gratification", i.e. tailoring media features to individual needs.

Individuals who contribute to nonprofits may choose to make donations via DC, or participate in discussions and increase their levels of civil engagement. At the organizational level, it is clear that DC enables easy and quick access to information. In today's global economy, this is identified with improved organizational performance (Ducheneaut & Watts, 2005). Earlier studies in voluntary organizations in the United Kingdom (Burt & Taylor, 2003) showed increased use of DC to reconfigure key information flows in support of enhanced campaigning and more effective user services. There is also evidence that nonprofits are able to exploit opportunities for radical shifts in organizational arrangements and thereby increase their social, economic, and political spheres of influence. The authors pointed out that the use of advanced technological communication devices has improved both efficiency and potential by comparison with previous periods, as have levels of integration of information within organizations, while the level and quality of coordination have risen substantially as well. Combining individual levels of contribution through DC with organizational criteria of performance - DP - in nonprofit settings is thus possible as long as DC approaches the stakeholders' needs and expectations properly, so that nonprofit DP is possible by increasing either effectiveness or efficiency (Mano, 2009).

Stakeholders are those individuals or groups who support an organization. According to Abzug and Webb (1999), stakeholders of NPOs include the community, competitors, clients, managers and employees, government suppliers, and private founders of organizational goals. Researchers of NPOs (Freeman, 1984; Winn & Keller, 2001) stress the dependence of the organization on its stakeholders, namely any group or individuals that may influence or be influenced by an organization working to achieve its goals. Similarly, Donaldson and Preston (1995) claimed that stakeholders are the investors (of financial or human resources) who have something to lose or gain as a result of organizational activities. Others view stakeholders as those with power, having legitimate and justified claims on an organization.

The stakeholders approach involves three dimensions: first, type of performance effectiveness vs .. efficiency; second, two types of stakeholders, i.e. public - recipients and providers of services at the national level; and private - i.e. all individual and organizational agents of support that does not involve public funding; and third, individual and organizational outcomes of DC. We apply the above dimensions to two basic types of nonprofits, namely service and advocacy.


**Low-Cost Sensors and Biological Signals**

Printed Edition of the Special Issue Published in *Sensors* Frédéric Dierick, Fabien Buisseret and Stéphanie Eggermont Edited by

www.mdpi.com/journal/sensors


**1. Introduction**

Sixty years ago, an article entitled *Adverse cerebral effects of anaesthesia on old people* by Dr. Bedfor was published in which he reported for the first time that general anaesthesia and surgery led to cognitive dysfunction in elderly patients [1]. This decline, known as postoperative cognitive dysfunction (POCD), typically persists for several weeks, sometimes a year, but in some people is permanent. Since then, the number of publications assessing POCD has been growing year by year, reflecting the increasing importance and the still remaining controversies over this condition [2].

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

One of the greatest achievements of modern medicine is the increase in life expectancy; however, as a consequence the world population is today ageing fast, with over 12.3% of the total being over 60 years old [3]. Moreover, life expectancy increased by 5 years between 2000 and 2015, the fastest growth since the 1960s [4]. Though it is one of our greatest achievements, it also poses big challenges as the ageing process is associated with biological and cognitive degeneration [5]. Recent advances in surgical, anaesthetic management and intensive care techniques are associated with a growing number of elderly people undergoing surgical procedures [6]. Consequently, complications associated with geriatric surgery, such as POCD, will become an increasingly common worldwide problem [7, 8]. Furthermore, POCD has been shown to be associated with long-term disability and higher health care costs. In addition, three-month POCD has been statistically associated with increased mortality [9].

POCD is difficult to define; in general it refers to a deterioration in cognition that occurs in the time period after surgery. To truly diagnose POCD, it is necessary to have tested the patient preoperatively (baseline) and determined how much of a decline occurred after surgery. As can be expected, in normal clinical contexts, patients do not usually undergo neuropsychological testing pre- and post-surgery [2, 10]. In consequence, there is a lack of accurate data and even the exact incidence of this condition is unknown [10]. Besides, behavioral responses to cognitive tests not only vary considerably in aged individuals compared with younger individuals, but also an enormous variability of cognitive decline exists across individuals [6, 11]. Additionally, the changes produced by the effects of ageing on cognitive function vary substantially through the different cognitive domains [11]. Likewise, different cognitive domains must be evaluated by specific tests [2]. Hence in order to diagnose and characterize POCD cases, it becomes necessary to carry out neuropsychological tests that assess different domains involved in cognitive function such as learning and memory, attention, psychomotor function and flexibility cognition [2, 10]. In addition, POCD is sometimes characterized by slight declines in cognitive function, making it essential that these tests should be sensitive enough to allow an accurate diagnosis based on the results of pre-and postoperative tests [10]. As a consequence, incidence rates reported may vary considerably according to the cognitive domains explored by different tests and timing [12].

POCD was initially associated with cardiac surgery and indeed was recognized as the most common complication in this intervention, presenting a high incidence [13, 14], although the incidence values vary considerably between different reports, ranging from approximately 30% to 80% at the time of discharge, 10–60% after 3–6 months and 20–60% after 6 months to 1 year [12–20]. This fact may be related to microembolic events that may cause focal cerebral infarcts during the use of the cardiopulmonary bypass pump [12, 21–24].

In recent times, in correlation with the continuingly increasing number of patients undergoing geriatric surgery, the interest in POCD has expanded to noncardiac surgery as well. So far, the major study assessing this condition was carried out by the International Study of Postoperative Cognitive Dysfunction and included 1218 patients older than 60 years old undergoing elective, noncardiac surgery [7]. Neuropsychological tests were administered before surgery and at 7 days and 3 months after intervention. This study reported a POCD incidence of 25% 1 week after surgery and 10% after 3 months. Additionally, the probability of POCD incidence in patients aged 70 and over at 3 months (14%) was two times higher than those aged 60 to 69 (7%). Hovens and collaborators [25] reported that the cognitive domains affected by cardiac surgery compared with noncardiac surgery seem to be different. While abdominal surgery affects hippocampal neuronal functioning and in consequence spatial memory, cardiac surgery seems to cause a more general change in inflammation and neuronal function [25].

Furthermore, there appears to exist an association between postoperative pain and cognitive impairment, exerting an influence over the patients' performance on certain cognitive tests [26–28]. Apart from the effect of the pain, the influence of postoperative analgesics should not be ruled out. In fact, successful postoperative pain management may be important in preventing POCD in elderly patients [35]. Additionally, cognitive impairment in elderly patients may also be influenced by stress produced by the hospitalization itself, the postoperative fatigue state, the unfamiliar environment and sleep deprivation [12, 28, 29].

The contribution of the anaesthesia to the development of POCD seems to be subject to discrepancies. When Silbert and colleagues [30] assessed general anaesthesia compared with spinal anaesthesia, no significant difference in the rates of POCD was found. In agreement with this, a meta-analysis carried on by Guay [31] did not find differences between general anaesthesia and regional anaesthesia with spontaneous breathing and sedation only in the development of permanent POCD after noncardiac surgery. Otherwise, another meta-analysis concluded that general anaesthesia, compared to other types of anaesthesia, may increase the risk of developing POCD [32]. This findings are supported by preclinical studies, which suggest that isoflurane anaesthesia administered at clinically relevant doses causes longterm cognitive impairment in unoperated animals [33–35]. However, other studies point towards an enhancement of the cognitive functions after anaesthesia inhalation [36–38].

Although major surgery is frequently associated with the development of POCD, minor surgery proved to decrease the cognitive function in the first postoperative week in elderly patients [39]. Moreover, independently from the nature of the surgical procedure, the only consistent risk factor that has been identified for POCD is advanced age [7, 9, 15, 39–41]. Apart from increasing age as a risk factor for POCD, other factors that can be enumerated are lower level of education, a history of previous cerebral vascular accident, a history of alcohol dependence, preoperative history of post-traumatic stress disorder, poor cognitive health, preceding development of POCD, respiratory complications, infectious complications and a second operation [9, 12, 41–43].


**2.2. Thermoelectric system of THU version 1.2**

Recently, an improved prototype of the THU v1.1 was designed, named THU v1.2. This second version mainly consists of three subsystems: a heating system, a ventilation system and a control system. The heating system is composed of 20 Peltier modules (Marlow Industries, Inc.) with a heat dissipation system. All Peltier modules are connected in parallel, require a voltage of 20 volts and have a heating capacity of 1 kW (1/4TR heating tonnage). The elements of heat dissipation system are composed of 20 finned heat sinks and four tangential fans. This second version has more insulation, better heat dissipation and lower power consumption. **Figure 2** shows the outside and inside views of THU v1.2 prototype.

In order to know the economical and thermal viability of the THU v1.2 prototype, an identical test room was built for a conventional air-conditioning system, as shown in **Figure 3**. The conventional air-conditioning system uses inverter technology to regulate the voltage, current and frequency of an air conditioner so that it consumes only the necessary energy. The used model in this work is the air-conditioning split (1X1 MSZ-HJ35VA Mitsubishi Split) with a heating capacity of 3.6 kW (1TR heating tonnage).

To provide a consistent baseline for comparative analysis, the authors show the technical information for the THU prototype and conventional air-conditioning system (**Table 1**).

#### **2.3. Design and operating principle**

The exterior image in this project is based on an opaque ventilated façade with an active mechanism (air grilles) that adapts to different environmental conditions and seeks maximum efficiency at all times. The activation mechanism adjusts the air chamber ventilation of the façade and the heating system. This means that during winter months, the grilles are shut to enhance the accumulation of heat inside a room. However, in the summer months, the grilles are opened to extract the excess heat from the system. It is relevant to mention that the initial configuration of the active ventilated façade is in accordance with the requirements under the regulation of the ventilation of the cavity of the ventilated façade. As is shown in **Table 2**, an enclosure of a light sheet metal, as a light element with low thermal inertia that allows an immediate response to external environmental conditions and a ventilation capacity of 50CFM in the room was selected.

The internal concept of the THU prototype consists of three layers, two air chamber and a HVAC system (thermoelectric system), as is shown in **Figure 4**. The first layer (external view) is composed of the metallic frame with two fans and a heat dissipation system. The fans allow the entrance of air to the external chamber (chamber connected to the outside environment), it passes through of the heat pipes and leaves external chamber eliminating the excess heat

**K/W)**

**Material Thicknesses (mm) Λ (W/mK) R (m2**

Sheet metal 0.8 — — Ventilated air chamber/sealed 100 — 0.18 Inner sheet 177.5 0.163 4.62 Semi-rigid rockwool panel 80 0.034 1.91 Sandwich panel 35 0.028 1.25 Rockwool panel 50 0.035 1.40 Plasterboard 12.5 0.25 0.05

**Table 2.** Technical parameters of the active ventilated façade THU v1.2.

**Figure 3.** Schematic diagram of conventional system v2.0: (a) top view, (b) inside view and (c) outside view.

Internal dimension (m) 4.0 × 2.4 × 2.5 3.75 × 2.10 × 2.0 3.75 × 2.1 × 2.0

Façade thickness (mm) 35 160 160 Dimension of chambers (cm) 100 × 10 100 × 10 No U of the façade (W/m2 K) 0.52 0.21 2.21 Double height No Yes Yes Roof thickness (mm) 35 127 127 U of the roof (W/m2 K) 0.52 0.21 0.21 Floor thickness (mm) 19 195 195 U of the floor (W/m2 K) 5.26 0.29 0.29

**Table 1.** Technical parameters of the prototypes.

**Parameter/component THU v1.0 THU v1.2 Conventional system V2.0**

Techno-Economic Analysis of a Peltier Heating Unit System Integrated into Ventilated Façade

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127

**Figure 2.** Integration of the thermoelectric system in THU v1.2: (a) top view, (b) inside view (air inlet and outlet and ceramic surface) and (c) outside view of the prototype with the grills to dissipate the heated/cooled air.

Techno-Economic Analysis of a Peltier Heating Unit System Integrated into Ventilated Façade http://dx.doi.org/10.5772/intechopen.76642 127

**Figure 3.** Schematic diagram of conventional system v2.0: (a) top view, (b) inside view and (c) outside view.

**Table 1.** Technical parameters of the prototypes.

**2.2. Thermoelectric system of THU version 1.2**

126 HVAC System

heating capacity of 3.6 kW (1TR heating tonnage).

**2.3. Design and operating principle**

ity of 50CFM in the room was selected.

**Figure 2** shows the outside and inside views of THU v1.2 prototype.

Recently, an improved prototype of the THU v1.1 was designed, named THU v1.2. This second version mainly consists of three subsystems: a heating system, a ventilation system and a control system. The heating system is composed of 20 Peltier modules (Marlow Industries, Inc.) with a heat dissipation system. All Peltier modules are connected in parallel, require a voltage of 20 volts and have a heating capacity of 1 kW (1/4TR heating tonnage). The elements of heat dissipation system are composed of 20 finned heat sinks and four tangential fans. This second version has more insulation, better heat dissipation and lower power consumption.

In order to know the economical and thermal viability of the THU v1.2 prototype, an identical test room was built for a conventional air-conditioning system, as shown in **Figure 3**. The conventional air-conditioning system uses inverter technology to regulate the voltage, current and frequency of an air conditioner so that it consumes only the necessary energy. The used model in this work is the air-conditioning split (1X1 MSZ-HJ35VA Mitsubishi Split) with a

To provide a consistent baseline for comparative analysis, the authors show the technical information for the THU prototype and conventional air-conditioning system (**Table 1**).

The exterior image in this project is based on an opaque ventilated façade with an active mechanism (air grilles) that adapts to different environmental conditions and seeks maximum efficiency at all times. The activation mechanism adjusts the air chamber ventilation of the façade and the heating system. This means that during winter months, the grilles are shut to enhance the accumulation of heat inside a room. However, in the summer months, the grilles are opened to extract the excess heat from the system. It is relevant to mention that the initial configuration of the active ventilated façade is in accordance with the requirements under the regulation of the ventilation of the cavity of the ventilated façade. As is shown in **Table 2**, an enclosure of a light sheet metal, as a light element with low thermal inertia that allows an immediate response to external environmental conditions and a ventilation capac-

**Figure 2.** Integration of the thermoelectric system in THU v1.2: (a) top view, (b) inside view (air inlet and outlet and

ceramic surface) and (c) outside view of the prototype with the grills to dissipate the heated/cooled air.

The internal concept of the THU prototype consists of three layers, two air chamber and a HVAC system (thermoelectric system), as is shown in **Figure 4**. The first layer (external view) is composed of the metallic frame with two fans and a heat dissipation system. The fans allow the entrance of air to the external chamber (chamber connected to the outside environment), it passes through of the heat pipes and leaves external chamber eliminating the excess heat

**Table 2.** Technical parameters of the active ventilated façade THU v1.2.

mainly govern the thermoelectric effect are the electric power and the heat flow. The electric power shows the difference between the heat dissipated on the hot side and the heat absorbed

Techno-Economic Analysis of a Peltier Heating Unit System Integrated into Ventilated Façade

*Pelect* = *qhot* − *qcold* = *V* ∙ *I* (1)

*qe*,*com* = *K*(*T* − *To*) (2)

*g T* − \_\_1 2 *I g*

*g T* + \_\_1 2 *I g*

where α is the total Seebeck coefficient (V/K), α = m(αp − αn), the subscripts p and n stand for p-type and n-type semiconductors, m is the number of Peltier cells, R is the total electrical resistance

S is the cross-sectional area of semiconductor arms, S is the cross-sectional area of semiconduc-

A key parameter used to measure the performance of any air-conditioning system is the COP, defined as the useful thermal power output per unit of heat power. Its mathematical expres-

The air-conditioned systems can be used in heating and cooling modes. In this work, the heating cycle is only considered, so the COP in heating mode for conventional system is given by [43]

*Ta* ′ − Δ *Tevap* ′ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ *Troom*

′ Δ *Tcond* ′ + *Tevap*

′ − *Ta*

is the ambient temperature outside the evaporator in the heating mode (° K), Troom

room air temperature outside the condenser in the heating mode (° K), Tcond

/Sn), ρ is the electrical resistivity, l is the length of the semiconductor arms,

is the operational electrical current of a multi-couple Peltier cell.

/l p + κn Sn /l n

is the heat absorbed at the cold side of the Peltier modules (W). The heat conduction

is the heat dissipated on the hot side (W)

http://dx.doi.org/10.5772/intechopen.76642

129

2 *R* + *K*(*T* − *To*) (3)

2 *R* + *K*(*T* − *To*) (4)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ *Input Power* (*kW*) (5)

, κ is the thermal conductivity of

′ (6)

′ is the

′ is the temperature

at the cold side of the Peltier modules, and this is given by

where I is the load current, V is the output voltage, qh

from the hot side to the cold side is given by

*q*1 = *I*

*q*1 = *I*

tor arms, K is the total thermal conductance, R = κp Sp

g

*COP*(*thermal*) = *Useful Power* (*kW*)

The heat flow is given by

and qc

and

(Ω), R = m(ρp I

where Ta ′ p /Sp + ρn I n

the semiconductor materials,I

sion can be given as follows [42]:

*COP*(*heat*) = 1 +

**Figure 4.** Schematic diagram of the design: (a) THU v1.1 prototype and (b) THU v1.2 prototype.

from the thermoelectric system. A relevant detail in the external view is that for THU v1.1, two axial fans were used, which were placed on the façade, while the second version THU v1.2 used two tangential fans, which were fixed in the lower part of the external chamber. This difference improves aesthetics and heat dissipation in the thermoelectric system.

The thermoelectric system is fixed in the second layer and its function is to separate the two chambers and supply heat to the room. Finally, the third layer connects the internal chamber with the room. This is composed of a group of heat sinks and two tangential fans (fixed in the lower part of the internal chamber). They allow the passage of air into the inner chamber for supplying hot air in the room. In this model, an air exit grill on the top of the wall was placed for extracting the cold air of the room.

#### **2.4. Mathematical model**

The Peltier modules consist of two or more elements of n-type- and p-type-doped semiconductor material that are electrically connected in series and thermally connected in parallel. These thermoelectric elements and their electrical interconnects are typically mounted between two ceramic substrates. Applying a voltage to a thermoelectric module creates a temperature difference. This temperature difference can be used to transfer heat from a cold side to a hot side and vice versa. Therefore, Peltier modules can be used to control the climate in rooms: to heat in winter and to cool in summer. In this regard, it is necessary to obtain a better heat transfer between the Peltier cells and the room air for increasing the heat transfer area of the ceramic plates with heat sinks [39, 40]. In this section, a brief overview of the basic equations that influence the functioning of a THU system is presented. The equations that mainly govern the thermoelectric effect are the electric power and the heat flow. The electric power shows the difference between the heat dissipated on the hot side and the heat absorbed at the cold side of the Peltier modules, and this is given by

$$P\_{\text{dett}} = q\_{\text{hot}} - q\_{\text{cold}} = V \cdot I \tag{1}$$

where I is the load current, V is the output voltage, qh is the heat dissipated on the hot side (W) and qc is the heat absorbed at the cold side of the Peltier modules (W). The heat conduction from the hot side to the cold side is given by

$$q\_{e,con} = \text{K}(T - T\_o) \tag{2}$$

The heat flow is given by

$$q\_1 = \ \text{al}\_g \ T - \frac{1}{2} I\_g^2 \ R + \text{K}(T - T\_o) \tag{3}$$

and

from the thermoelectric system. A relevant detail in the external view is that for THU v1.1, two axial fans were used, which were placed on the façade, while the second version THU v1.2 used two tangential fans, which were fixed in the lower part of the external chamber. This

The thermoelectric system is fixed in the second layer and its function is to separate the two chambers and supply heat to the room. Finally, the third layer connects the internal chamber with the room. This is composed of a group of heat sinks and two tangential fans (fixed in the lower part of the internal chamber). They allow the passage of air into the inner chamber for supplying hot air in the room. In this model, an air exit grill on the top of the wall was placed

The Peltier modules consist of two or more elements of n-type- and p-type-doped semiconductor material that are electrically connected in series and thermally connected in parallel. These thermoelectric elements and their electrical interconnects are typically mounted between two ceramic substrates. Applying a voltage to a thermoelectric module creates a temperature difference. This temperature difference can be used to transfer heat from a cold side to a hot side and vice versa. Therefore, Peltier modules can be used to control the climate in rooms: to heat in winter and to cool in summer. In this regard, it is necessary to obtain a better heat transfer between the Peltier cells and the room air for increasing the heat transfer area of the ceramic plates with heat sinks [39, 40]. In this section, a brief overview of the basic equations that influence the functioning of a THU system is presented. The equations that

difference improves aesthetics and heat dissipation in the thermoelectric system.

**Figure 4.** Schematic diagram of the design: (a) THU v1.1 prototype and (b) THU v1.2 prototype.

for extracting the cold air of the room.

**2.4. Mathematical model**

128 HVAC System

$$q\_1 = \ \text{aI}\_g \ T + \frac{1}{2} \text{I}\_g^{\text{-}} \text{R} + \text{K}(T - T\_o) \tag{4}$$

where α is the total Seebeck coefficient (V/K), α = m(αp − αn), the subscripts p and n stand for p-type and n-type semiconductors, m is the number of Peltier cells, R is the total electrical resistance (Ω), R = m(ρp I p /Sp + ρn I n /Sn), ρ is the electrical resistivity, l is the length of the semiconductor arms, S is the cross-sectional area of semiconductor arms, S is the cross-sectional area of semiconductor arms, K is the total thermal conductance, R = κp Sp /l p + κn Sn /l n , κ is the thermal conductivity of the semiconductor materials,I g is the operational electrical current of a multi-couple Peltier cell.

A key parameter used to measure the performance of any air-conditioning system is the COP, defined as the useful thermal power output per unit of heat power. Its mathematical expression can be given as follows [42]:

$$\text{U} = \text{S} \cdot \text{L}$$

$$\text{COP}\_{\text{(blerman)}} = \frac{\text{Us} \text{fefall Power (k}\text{W}\text{)}}{\text{Input Power (k}\text{W}\text{)}} \tag{5}$$

The air-conditioned systems can be used in heating and cooling modes. In this work, the heating cycle is only considered, so the COP in heating mode for conventional system is given by [43]

\_Yuc\_ кону сопусимлича, эм ше соп плівашан поме мо сичсимлов узсип з руслоу [ $\mu$ ]

$$\text{COP}\_{\text{(bat)}} = 1 + \frac{T\_s' - \Lambda \ T\_{sup}'}{T\_{sum}' - T\_s' \Lambda \ T\_{sup}' + T\_{sup}'} \tag{6}$$

where Ta ′ is the ambient temperature outside the evaporator in the heating mode (° K), Troom ′ is the room air temperature outside the condenser in the heating mode (° K), Tcond ′ is the temperature difference between refrigerant in condenser and ambient temperature (° K) and Tevap ′ is the temperature in the evaporator (° K).

In the case of thermoelectric system, the ideal COP in the heating mode is given by [43]

$$\text{COP}\_{\text{(heat)}} = \frac{T\_h}{T\_h - T\_c} \left( 1 - 2 \frac{1 + Z \, T\_{w=1}}{Z \, T\_m} \right) \tag{7}$$

the operational lifetime of thermoelectric device reported by Marlow Industries. Inc. [41] is in the range of 20,000–350,000 h at normal conditions, and Mitsubishi Company guarantees 15 years for inverter air-conditioning [44]. It is estimated that the physical lifetime of the structure is 30–40 years because the structural design combines durability, resistance and anti-corrosive materials. Also, it is assumed that the technological lifetime of the THU system is as long as the lifespan of the building (30–40 years), since it has a digital display that allows controlling the Peltier system and a sophisticated PLC that can be reprogrammed to the user necessities.

In addition to an economic assessment, the THU systems have social benefits that play an important role in taking care of the environment. In other words, the benefits associated with the use of THU systems are mainly related to reducing carbon dioxide emission. THU sys-

systems, because they do not have a working fluid. Therefore, THU systems are a good option for avoiding greenhouse gas emissions. Their electronic components can also be recycled. Moreover, a photovoltaic system could be added into this system to generate electricity and

The investment costs of the THU v1.2 prototype and conventional air-conditioning system are reported in **Table 3**. The results show that the overall cost of this protect was approximately 84,860 Euros. This cost is because the authors considered the architectural and engineering aspects of both prototypes. Also, it can be observed that the highest value was for the engineering costs at 69.27% of the total investment cost, so that it is suggested that the designer

The improvements of THU v1.1 prototype reduced the total investment cost by 30%. This percentage is directed directly related to the design, manufacture process and size of the prototype. On the other hand, **Table 3** shows that the supply/handing cost represented no more than 18.89% of the investment cost and that the auxiliary cost contributed only 14.54%, as it was expected. The above data indicate that the design plays an important role in engineering aspects. This means that the designer should select appropriate construction materials, the number of Peltier cells and the distribution of each system considering their cost. Also, the results indicate that the conventional v2.0 system is more economically viable than THU v1.2 because the THU system is the first product built in a prefabricated module. This prototype

would be more viable if a considerable number of THU systems were manufactured.

Concerning manufacturing process of heating system, it was noted that investment costs are directly influenced by the size and number of Peltier modules, that is, an increase of Peltier modules increases the number of finned heat sinks, so that the investment costs increase. Also, the use of heat pipe sinks increases the investment costs by 30%. Although the heat pipe sinks offer better performance in terms of heat dissipation, the manufacturing process of a finned heat sink is less complicated than that of a heat pipe sink, so that the finned heat sink

could reduce the annual operational costs, according to [14, 15].

has to pay attention for proposing competitive and viable prototypes.

in the operational and maintenance phase as inverter air-conditioning

Techno-Economic Analysis of a Peltier Heating Unit System Integrated into Ventilated Façade

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131

**3.3. Environmental benefits**

**4. Results and discussion**

tems do not emit CO2

where Th is the hot side temperature at ceramic plate location in a thermoelectric module (° K), Tc is the cold side temperature at ceramic plate location in a thermoelectric module (° K), Z is the figure of merit of thermocouple and Tm is the arithmetical average temperature of a thermocouple(° K) .


**10. Focus on pediatric stroke**

Pediatric stroke is classified into infant and childhood stroke. Infant (neonatal or perinatal) stroke is defined as occurring between 28 weeks gestation and 28 days of postnatal age. The incidence is estimated as one in every four thousand live birth per year in the United Sates81. Ischemic stroke is twice as common as hemorrhagic stroke. According to a retrospective review, the most common discharge diagnoses conjunction with neonatal stroke included infection, cardiac disorders, and blood disorders. Less than 5% was associated with birth asphyxia81.

Abnormal muscle tone leads to abnormal positioning and abnormal movement pattern, and vice versa. To break this vicious cycle, comprehensive rehabilitation should include muscle tone management, proper bracing and positioning, and stimulation control. Repetitive task training is a commonly used in current rehabilitation therapy, but a literature review

Constraint-induced movement therapy (CIMT or CIT) was introduced with a hypothesis of forceful usage of paralytic arm facilitate neuroplasticity of the brain, which in turn leads to recovery of the arm motor function64. There are many supportive reports to its effectiveness65, 66, however, there is a lack of large randomized controlled study67. CIMT is indicated for subjects who have no significant spasticity and some strength of the paralyzed

Development in neruoscience and computer technology provides novel ideas to overcome the limitation of traditional rehabilitation for stroke. Originally, robotic treatment was introduced to alleviate the labor-intensive aspects of physical therapy by preinstalled programs to perform a goal-directed movement autonoumously or semi-autonomously69. It induces movement of paralyzed limbs by activation of the motor cortex of the side of the lesion and the movement of the limb also activates the motor cortex in a positive feedback. Most of devices are designed to lead task-oriented movement by intensive repetitive patterns. Functional brain MRI studies of robotic treatments, demonstrated an increased activation of the sensorimotor cortex during grasping tasks greater than non-practiced tasks70. However, the effectiveness of robotic treatment is still in question71-73. It is likely effective for shoulder and elbow function recovery, but may lack effectiveness of hand

EEG/MEG-based motor imagery brain-computer interface utilizes neuronal activities of the motor cortex of lesion side while performing motor imagery74, 75. Currently combined brain-

Virtual reality training, although needs further study, appears to be effective in

Generally, poor prognostic factors include prolonged flaccidity of paralyzed limb, right hemisphere lesion with hemi-neglect, cognitive impairment, old age (>74 years), anterior circulation, and large lesion size. Also spouse at home, hypothermia at acute phase, and

Pediatric stroke is classified into infant and childhood stroke. Infant (neonatal or perinatal) stroke is defined as occurring between 28 weeks gestation and 28 days of postnatal age. The incidence is estimated as one in every four thousand live birth per year in the United Sates81. Ischemic stroke is twice as common as hemorrhagic stroke. According to a retrospective review, the most common discharge diagnoses conjunction with neonatal stroke included infection, cardiac disorders, and blood disorders. Less than 5% was associated with birth

reported it is not effective in upper extremity motor function63.

upper extremity. It is not effective in acute phase of stroke68.

computer interface with robotic feedback technique is being tried76.

function improvement.

**9. Prognostic factors**

asphyxia81.

improvement of motor function77, 78.

**10. Focus on pediatric stroke**

absent co-morbidities are good predictors79, 80.

Childhood stroke is defined as occurring between 30 days of postnatal age and 18 years old. The incidence is reported 2-3/100,000 per year in US81, 2.7/100,000 in Canada (ischemic stroke only)82, and 13/100,000 in France83. Its mortality rate is reported 7-28% and higher in males than females and in blacks than white, respectively. Stroke is less common in children than in adults, but is one of the top ten causes of death in children in the US. It results in one of the leading causes of disability in young generations. The pathophysiology of childhood stroke is same as adults, but underlying premorbidities or etiologies are different. Most of adult stroke patients have pre-existing medical conditions, such as hypertension, diabetes mellitus, hyperlipidemia, arteriosclerosis, heart disease, or obesity, but in contrast one third of child stroke patients do not have any evident pre-existing medical conditions. In childhood stroke, congenital heart disease is the most common known etiology (about 30%), and sickle cell disease is the leading cause of stroke in African American ethnic group. Arteriovenous malformation is the leading cause of hemorrhagic stroke in childhood. Various coagulation disorders-factor V Leiden and prothrombin mutation, protein C and S deficiency, anti-phospholipid antibody, and inherited coagulation abnormalities and arterial vasculitis are related to pediatric strokes. Venous stroke is not uncommon in children. Venous:arterial stroke ratio is 1:4-6 in non-hemorrhagic stroke84. Venous stroke develops, when cerebral venous drainage to the internal jugular veins is significantly obstructed by thrombosis in the cerebral venous sinus (sinus venous thrombosis). The obstructed venous drainage consequently impedes arterial supply to the brain. Progressive insufficient arterial supply to the brain eventually leads to ischemia. Because of this slow process, compared with arterial stroke, clinical symptoms and signs progress slowly in venous stroke. High risks of sinus venous thrombosis are head and neck infection (meningitis, mastoiditis), dehydration, coagulation disorder, and perinatal complications. The outcome of a venous stroke is excellent.

The ratio of hemorrhagic to nonhemorrhagic stroke in childhood stroke is about 5:3 in the US85 . It is understood that the incidence of homorrhagic stroke is higher than adult, but it is similar to a recent stroke registry data3. Diagnostic interventions of pediatric stroke are similar to those of adult stroke. In addition, hematologic and metabolic work up for coagulopathy is important. It is not easy to recognize neonatal stroke because of limited clinical presentations. It is partially plausible to explain that patients with hemiplegic cerebral palsy might have unrecognized neonatal stroke. It is supported by the fact that patients with hemiplegic cerebral palsy showed elevated antiphospholipid and/or factor V Leiden mutation than normal control86-87. Patients with sickle cell disease has 200-400 times high risk and 50% of recurrence risk by three years.

In order to prevent stroke recurrence, aspirin is recommended for high risk of stroke patients in both adult and children. Apirin used for stroke prophylaxis does not complicate Reye's syndrome in children. Regular brain MRA is suggested to patient with hemorrhagic stroke secondary to aneurysm.

Since human cerebral hemispheres are already specialized at an early stage of development, pediatric stroke patients also demonstrate adult pattern of side specificity for brain lesions88- 89. Therefore clinical features are side specific and similar to adult stroke.

Outcomes vary among studies because of differences in population characteristics, stroke type, duration of follow-up, and outcomes measurement tools. Long-term outcome study

Stroke Rehabilitation 31

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[9] Howard G, Till JS, Toole JF, Matthews C, Truscott BL. Factors influencing return to work

[10] Mosch SC, Max JE, Tranel D. A matched lesion analysis of childhood versus adult-onset brain injury due to unilateral stroke. Cog Behav Neurol 18(1):5-17, 2005. [11] Kwakkel G, Kollen BJ, van der Grond J, Prevo AJH. Probability of regaining dexterity in

[12] Stone SP, Patel P, Greenwood RJ, Halligan PW. Measuring visual neglect in acute stroke

[13] Bowen A, McKenna K, Tallis R. Reasons for variability in the reported rate of occurrence of unilateral spatial neglect after stroke. Stroke 30:1196-1202, 1999. [14] Katz N, Hartman-Maeir A, ring H, Soroker N. Functional disability and rehabilitation

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[16] Jehkonen M, Ahonen J-P, Dastidar P, Koivisto A-M, Laippala P, Vilkki J, Molnar G,

[17] Jorgensen HS, Nakayama H, Raaschou HO, Olsen TS. Intracerebral hemorrhage versus

[18] Leung AW, Cheng SK, Mak AK, Leung KK, Li LS, Lee TM. Functional gain in

[19] Katrak PH, Black D, Peeva V. Do stroke patients with intracerebral hemorrhage have a

[20] Paolucci S, Antonucci G, Grasso MG, Bragoni M, Coiro P. Functional outcome of

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Investigators. Dose hemispheric lateralization influence functional and cardiovascular outcomes after stroke?: an analysis of placebo-treated patients from

the flaccid upper extremity: impact of severity of paresis and time since onset in

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outcome in right hemisphere damage patients with and without unilateral spatial

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showed complete recovery rate without residual impairment in 14% of patients with nonhemorrhagic stroke90 and 25% in hemorrhagic stroke91, respectively. In adult strokes, hemorrhagic stroke has higher mortality (23%) than non-hemorrhagic stroke91.

In the long-term, cognitive impairment is significant in childhood stroke, and IQ (Intellectual Quotation) ranges widely and is lower than average90, 92, 93. As imagined, VIQ (Verbal IQ) is higher than PIQ (Performance IQ) in children with right hemisphere lesion, and PIQ is higher than VIQ in left hemisphere lesion90, 93. In spite of cognitive impairment, most of children return to mainstream school with/without support57, 90. Regardless of residual impairments and disabilities, they feel healthy and happy as normal children would94.

General survival rate of pediatric stroke is better than adults95, 96. 5 year survival rate is 85%, and residual neurological deficits of 75% (hemiparesis, epilepsy, learning disabilities, visual field deficits, mental retardation)97. Idiopathic stroke have better prognosis than stroke associated with cardiac disease98. It is controversial but generally age is also an important prognostic factor98. The functional outcome of childhood stroke is more favorable than that of adult one. However, it is reported that infant stroke has poorer outcome than childhood stroke.

Poor outcome predictors are multiple cortical dysfunction, initial symptoms with altered level of consciousness with/without seizure, middle cerebral artery lesion, infant age onset, persistence of hemiparesis 1 month after stroke, and bilateral hemisphere lesions57,90, 93,99, 100.

School re-entry is the final rehabilitation goal for children with stroke. A neuropsychological test including IQ indicates the details of the cognitive impairments. Based on the test results, school re-entry might be planned. Depending on medical conditions and the test results, home bound education, part time student, full time student, or classroom modification might be advised.


*Article* **Orthodoxy and Evangelicalism: An Overview of Their Relationship from the Perspective of Moral Values**

**Daniel Buda 1,2**

**Abstract:** Orthodox–Evangelical relationships are dominated by proselytism (at least in Eastern Europe and in the former Soviet Union). This is understood as church conversion practiced through unfair means among people who are already Christians, belonging to so-called "historical churches." However, beyond it, there is a real potential for cooperation using moral values as a starting point. As there is an increasing disagreement between the Orthodox and mainline Protestant on moral values, the Orthodox and Evangelicals might increase their cooperation as they witness traditional values of Christianity. This kind of cooperation might be partially contextual, but it is based on Biblicism, which both Orthodox and Evangelicals share as a core value. As this cooperation, based on shared moral values, certainly has real potential, and has to be used for the good of Christianity, it might also have its limitations. Orthodox Christians and Evangelicals have shared common moral values, but each one of them might interpret the content of these values differently. One of the differences in interpreting and explaining the content of moral values might be given by the different interpretations of what is called church tradition.

**Keywords:** orthodox and evangelicals; ecumenical movement; proselytism; World Council of Churches; moral values