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A CW capable inline electron cyclotron emission (ECE) separation system for feedback control, featuring oversized corrugated waveguides, is commissioned on ASDEX upgrade (AUG). The system is based on a combination of a polarization independent, non-resonant, Mach-Zehnder diplexer equipped with dielectric plate beam splitters [2, 3] employed as corrugated oversized waveguide filter, and a resonant Fast Directional Switch, FADIS [4, 5, 6, 7] as ECE/ECCD separation system. This paper presents an overview of the system, the low power characterisation tests and first high power commissioning on AUG.

Background: Surgically repairing rotator cuff tears with a higher extent of fatty infiltration is controversial. Current evidence supports performing rotator cuff repair in patients exhibiting Goutallier stage 3-4 fatty infiltration. However, the presence of retraction complicates accurate assessment using the Goutallier Classification, particularly on the lateral Y-view. A shift towards classifying fatty infiltration in more medial regions may enhance the precision of tissue quality quantification. The objective of this study was to analyze the uniformity of fatty infiltration within the entire supraspinatus muscle using the Goutallier Classification across three scapular Y-view sections and to examine the association between Goutallier grade, tangent sign, and modified Patte stage., Methods: A retrospective evaluation was conducted on preoperative magnetic resonance imaging (MRI) scans from a consecutive series of 97 patients who had previously undergone arthroscopic rotator cuff repairs. Three supraspinatus sections on the MRI sagittal plane were identified: the lateral Y-view (section one), a medial section at the suprascapular notch anatomical landmark (section two), and a section 3 cm medial from the suprascapular notch Medial Scapular Body (section three). Goutallier grade, tangent sign, and modified Patte stage were used to evaluate fatty infiltration, muscle atrophy, and tendon retraction, respectively., Results: Section one had the highest Goutallier grade, while section three had the lowest. Intra-observer rest retest reliability analysis showed excellent consistency in all sections with section one (ICC=0.920, 95% CI), section two (ICC=0.917, 95% CI), and section three (ICC=0.923, 95% CI) for Goutallier grade. Inter-observer reliability analysis also revealed excellent consistency in sections one (ICC=0.951, 95% CI), section two (ICC=0.949, 95% CI), and section three (ICC=0.922, 95% CI) for Goutallier grade. A strong correlation was observed between Goutallier grade and modified Patte stage (τb=0.43-0.56, p=0.001), and between Goutallier grade and tangent sign (τb=0.43-0.54, p=0.001) across all sections., Conclusion: The severity of fatty infiltration within the supraspinatus muscle belly is inconsistent, with the lateral portion being the most severe and the medial portion the least severe. Goutallier grade demonstrates a strong correlation with tangent sign and modified Patte stage. This suggests that tendon retraction results in a potential overestimation in the amount of fatty infiltration defining some tears unjustly irreparable when measuring at the traditionally described lateral Y-view position compared with 3cm medial., (Copyright © 2024. Published by Elsevier Inc.)

Background: The degree of atrophy and fatty infiltration of rotator cuff muscle belly is a key predictor for cuff repairability. Traditionally, Goutallier grading of fatty infiltration is assessed at sagittal scapular Y-view. Massive rotator cuff tears are associated with tendon retraction and medial retraction of cuff musculature, resulting in medialization of the muscle bulk. Thus, standard Y-view can misrepresent the region of interest and may misguide clinicians when assessing repairability. It is hypothesized that by assessing the muscle belly with multiple medial sagittal magnetic resonance imaging (MRI) sections at the medial scapular body, the Medial Scapular Body-Goutallier Classification (MSB-GC) will improve reliability and repeatability, giving a more representative approximation to the degree of fatty infiltration, as compared with the original Y-view., Methods: Fatty infiltration of the rotator cuff muscles were classified based on the Goutallier grade (0-4) at 3 defined sections: section 1, original Y-view; section 2, level of suprascapular notch; and section 3, 3 cm medial to the suprascapular notch on MRI scans. Six subspecialist fellowship-trained shoulder surgeons and 3 musculoskeletal radiologists independently evaluated deidentified MRI scans of included patients., Results: Of 80 scans, 78% (n = 62) were massive cuff tears involving the supraspinatus, infraspinatus, and subscapularis tendons. Interobserver reliability (consistency between observers) for Goutallier grade was excellent for all 3 predefined sections (range: 0.87-0.95). Intraobserver reliability (repeatability) for Goutallier grade was excellent for all 3 sections and 4 rotator cuff muscles (range: 0.83-0.97). There was a moderate to strong positive correlation of Goutallier grades between sections 1 and 3 and between sections 2 and 3 and these were statistically significant (P < .001). There was a reduction in the severity of fatty infiltration on the Goutallier classification from sections 1 to 3 across all muscles: 42.5% of both supraspinatus and infraspinatus were downgraded by 1, 20% of supraspinatus and 3.8% of infraspinatus were downgraded by 2, and 2.5% of supraspinatus were downgraded by 3., Conclusion: This study found that applying the Goutallier classification to more medial MRI sections (MSB-GC) resulted in assignment of lower grades for all rotator cuff muscles. Additionally, this method demonstrated excellent test-retest reliability and repeatability. Inclusion of a more medial view or whole scapula on MRI, especially in advanced levels of tear retraction, could be more reliable and representative for assessment of the degree of fatty infiltration within the muscle bulk that could help predict tear repairability and therefore improve clinical decision making, which should be studied further in clinical studies., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Musculoskeletal conditions affect an estimated 1.7 billion people worldwide, causing intense pain and disability. These conditions lead to 30 million emergency room visits yearly, and the numbers are only increasing. However, diagnosing musculoskeletal issues can be challenging, especially in emergencies where quick decisions are necessary. Deep learning (DL) has shown promise in various medical applications. However, previous methods had poor performance and a lack of transparency in detecting shoulder abnormalities on X-ray images due to a lack of training data and better representation of features. This often resulted in overfitting, poor generalisation, and potential bias in decision-making. To address these issues, a new trustworthy DL framework has been proposed to detect shoulder abnormalities (such as fractures, deformities, and arthritis) using X-ray images. The framework consists of two parts: same-domain transfer learning (TL) to mitigate imageNet mismatch and feature fusion to reduce error rates and improve trust in the final result. Same-domain TL involves training pre-trained models on a large number of labelled X-ray images from various body parts and fine-tuning them on the target dataset of shoulder X-ray images. Feature fusion combines the extracted features with seven DL models to train several ML classifiers. The proposed framework achieved an excellent accuracy rate of 99.2%, F1Score of 99.2%, and Cohen's kappa of 98.5%. Furthermore, the accuracy of the results was validated using three visualisation tools, including gradient-based class activation heat map (Grad CAM), activation visualisation, and locally interpretable model-independent explanations (LIME). The proposed framework outperformed previous DL methods and three orthopaedic surgeons invited to classify the test set, who obtained an average accuracy of 79.1%. The proposed framework has proven effective and robust, improving generalisation and increasing trust in the final results., Competing Interests: NO authors have competing interests., (Copyright: © 2024 Alzubaidi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Total shoulder arthroplasty (TSA) has been the gold standard of care for end-stage glenohumeral arthritis. Outcomes are varied and have been affected by both patient and implant characteristics. Patient factors, such as age, preoperative diagnosis, and preoperative glenoid morphology, can affect the outcomes after TSA. Similarly, the different glenoid and humeral component designs significantly affect the survivorship of TSA. Significant evolution has occurred in the design of the glenoid component with the aim of decreasing the glenoid-sided causes of failure in TSA. On the other hand, focus on the humeral component has been increasing as well, with a trend towards using shorter humeral stems. This article aims to look at the outcomes of TSA as affected by the various patient characteristics and design options for the glenoid and the humeral components. This review also aims to compare survivorship data from global literature and the Australian joint replacement registry and to provide insights into the implant combination that may provide the best patient outcome., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Shoulder Injury Related to Vaccine Administration (SIRVA) is a rare disorder characterized by persistent shoulder pain and limited range of motion presenting within 48 h after vaccine administration. With the widespread distribution of the COVID-19 vaccine, the incidence of SIRVA is expected to rise. This sudden rise in vaccine administration presents an ideal opportunity to estimate the prevalence of SIRVA and to better characterize SIRVA., Objective: This study aims to investigate the prevalence of SIRVA following COVID-19 vaccine administration among hospital workers in the Netherlands., Methods: A questionnaire was sent to all hospital workers from a single non-academic hospital in the Netherlands. Respondents who had active SIRVA complaints were invited for an outpatient orthopaedic clinic assessment. Data was collected on participant characteristics and physical examination including assessment of active and passive range of motion (ROM). An ultrasound was performed to identify potential abnormalities., Results: 32 out of 981 (3.3%) respondents reported shoulder pain with limited ROM occurring within 48 h after vaccine administration lasting for at least 7 days. Of these 32 respondents with SIRVA, 18 (56.2%) still reported active symptoms at the time of the survey. Clinical examination of 13 (72.2%) respondents with active SIRVA complaints showed limited glenohumeral ROM, limitations in activities of daily living and injection site pain. Twelve out of thirteen (92.3%) respondents with active SIRVA complaints showed abnormalities of the soft-tissue of the shoulder on ultrasound. Physiotherapy was the most common treatment modality for persistent SIRVA complaints (38.9%)., Conclusions: The prevalence of SIRVA is estimated at 3% in the adult working population. Signs and symptoms of SIRVA are variable in severity, localization and timing. Soft-tissue abnormalities is the most common clinical sign. This study contributes to clinician's knowledge on SIRVA, aiding in early recognition and treatment, which are imperative for prevention of persistent and severe shoulder pathology., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Revision shoulder arthroplasty is increasing with the number of primary shoulder replacements rising globally. Complex primary and revisions of shoulder arthroplasties pose specific challenges for the surgeon, which must be addressed preoperatively and intraoperatively. This article aimed to present strategies for the management of revision of shoulder arthroplasties through a single-stage approach. Preoperatively, patient factors, such as age, comorbidities, and bone quality, should be considered. The use of planning software can aid in accurately evaluating implants in situ and predict bony anatomy that will remain after explantation during the revision surgery. The planning from such software can then be executed with the help of mixed reality technology to allow accurate implant placement. Single-stage revision is performed in two steps (debridement as first step, implantation and reconstruction as the second step), guided by the following principles: adequate debridement while preserving key soft tissue attachments (i.e., rotator cuff, pectoralis major, latissimus dorsi, deltoid), restoration of glenoid joint line using bone grafting, restoration of humeral length, reconstruction and/or reattachment of soft tissues, and strict compliance with the postoperative antibiotic regimen. Preliminary results of single-stage revision shoulder arthroplasty show improvement in patient outcomes (mean 1 year), successful treatment of infection for those diagnosed with periprosthetic joint infection, and improved cost-benefit parameters for the healthcare system.

Background: Since January 2021, over 24 million COVID-19 vaccines have been administered. Rarely vaccination in the deltoid muscle may lead to complications in the shoulder, called SIRVA (shoulder injury related to vaccine administration). General knowledge on SIRVA amongst doctors and other healthcare workers is lacking. However, due to the large amount of vaccinations which have been administered over the last year, SIRVA is seen more often., Case Report: In this report, two cases of SIRVA due to septic arthritis and a shoulder abscess after administration of a COVID-19 vaccination, are described., Conclusion: SIRVA should be considered in case of shoulder complaints which persist longer than 48 hours after vaccination. Timely diagnosis and treatment by either the general practitioner or orthopaedic surgeon should be conducted to prevent long-term damage to the shoulder joint. Use of the correct vaccination technique is important to prevent the occurrence of SIRVA.

Objective: The objective of this study is to study familial inheritance for Blount disease to create better understanding of the aetiology of Blount disease., Methods: After reviewing patient files and conventional roentgenologic imaging, 139 patients with Blount disease were included in this cross-sectional study, of which 102 patients were interviewed. During the interviews, patient characteristics and family history were collected. Blood samples were taken from five patients and three families and a whole exome sequencing was performed., Results: Although patients came from all over the country, 90% of the patients belonged to the Akan tribe. A positive family history was found in 63 families (62%), of which, almost two-third had a positive family history in a first-degree family member. In most of the cases (64%), the varus legs resolved over time. In 9%, severe bowing remained 'just like the patient'. The results of the whole exome sequencing did not show a genetic predisposition., Conclusion: This study describes a large group of Blount patients. Because of the high numbers of positive family history and the centralisation of patients in the Akan region, a familial predisposition is suggested. Further genetic research is essential for better understanding of the possible multifactorial aetiology in Blount disease., Competing Interests: Competing interests: No, there are no competing interests., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To assess the interchangeability of various existing answering scales within the subjective part of the Constant-Murley Score (CMS) and to determine the effect of the different answering scales on the inter- and intraobserver reliability., Methods: In this prospective, single-center, cross-sectional trial, patients with shoulder problems were included from June to September 2018. Subjects recruited were 18 years or older, presented various shoulder complaints, e.g., diagnosis of osteoarthritis, subacromial pain syndrome, rotator cuff or biceps tendon problems, or frozen shoulder. An extended version of the CMS was prepared including the same questions multiple times but with varying answer scales. Six versions were made with random order of the questions. The answering scales were a verbal and paper based visual analog scale (VAS), smiley face scale, Numeric Rating Scale (NRS), and categories. Internal consistency of the various CMS, Spearman correlation coefficients, intraobserver, and interobserver agreement was assessed (ICC)., Results: In total, 93 patients were included. The total CMS using the paper-based VAS, smiley face score, and NRS were 46.9 ± 19.4, 45.2 ± 18.5, and 45.0 ± 18.7. Correlations of the total scores of the different versions varied from 0.98 to 0.99. CMS-category versus CMS-smiley face score and CMS-category versus CMS-NRS pain were significantly different ( P  = .02 and P  = .01). Good internal consistency (0.76-0.79) and acceptable inter- and intraobserver reliability were found (ICC: 0.89-0.97, 0.98-0.99; P < .001)., Conclusions: The different answering scales for the subjective subscales within the CMS for pain, work, and recreational activity were not interchangeable on item level and significantly influenced the total CMS score. Differences were below the smallest detectable change and interpreted as not clinically relevant. Particularly on item level, data from different studies cannot be pooled and compared when different answering scales are being used. The inter- and intraobserver reliability were excellent., Level of Evidence: Level I, prospective cross-sectional study., (© 2021 by the Arthroscopy Association of North America. Published by Elsevier Inc.)

Blount's disease or bowed leg deformity, is a unilateral or bilateral growth deformity of the medial proximal tibia that leads to a tibial varus deformity. A distinction can be made in an early and late onset type. The disease seems to have a predisposition for certain descends. Since the first publication of Blount's disease, different hypotheses on the aetiology are proposed but no consensus exists. The objective of this study is to provide an overview of the available hypotheses on the aetiology of Blount's disease since its first description and assessment of the available level of evidence, the quality of evidence and the occurrence of bias supporting these individual hypotheses. A systematic search according to the PRISMA statement was conducted using PubMed, MEDLINE, EMBASE and the Cochrane Library using a broad combination of terminology to ascertain a complete selection. Proper MESH search criteria were formulated and the bibliographic search was limited to English and Dutch language articles. Articles with no mention of aetiology or a disease related to Blount's were excluded. Level of evidence and types of bias were assessed. Thirty-two articles that discuss the aetiology of Blount's disease were selected. A variety of hypotheses was postulated in these articles with most research in the field of increased mechanical pressure (obesity, early walking age) and race (descend). Blount's disease most likely has a multifactorial origin with influence of genetic and racial predisposition, increased mechanical pressure on the growth plate as a consequence of obesity or early walking age and possibly also nutrition. However, the exact aetiology remains unclear, the probable explanation is that multifactorial factors are all contributing to the development of Blount's disease. Histological research has shown that a disorganization of bone and cartilage structures on the medial side of the proximal tibial physis is present in patients with Blount's disease. Based on the available evidence on the aetiology of Blount's disease, we conclude that it is multifactorial. Most papers focus only on one hypotheses of Blount's disease occurrence and all are characterized as low level of evidence. There seems to be a preference for certain descends. Further research on especially genetic predisposition is needed to provide more insight in this factor of Blount's disease.

Introduction: For patients who are diagnosed with lesions of the rotator cuff that present advanced levels of fatty degeneration, arthroscopic repair of the rotator cuff remains controversial. This controversy can be attributed to the frequently reported high failure rate of the tendon fixation and the fact that it remains unclear why repair for these tears results in significant clinical improvement independent of the occurrence of such a re-tear. Recent publications have reported comparable clinical improvements when merely a tenotomy of the long head of the biceps tendon was performed and the rotator cuff tear was left untreated. These observations raise questions on the value of performing the more extensive cuff repairs in degenerative cuff tears. Even more, rehabilitation after an isolated tenotomy is much less cumbersome as compared with rehabilitation after rotator cuff repair and, therefore, might result in improved patient satisfaction. The goal of this trial is to study function and quality-of-life of patients undergoing arthroscopic biceps tenotomy with or without an additional cuff repair and to include an economic evaluation., Methods and Analysis: This multicentre randomised controlled non-inferiority trial, including an economic evaluation, is designed to compare the short-term and long-term outcome of patients who underwent an arthroscopic tenotomy of the long head of the biceps tendon with or without a cuff repair. We will include 172 patients with stage 2-3 Goutallier fatty infiltration cuff tears and with clinical symptoms of biceps pathology. Primary outcome is the rotator cuff specific quality-of-life (Western Ontario Rotator Cuff index) on the short term (6 months postoperatively). Secondary outcomes are quality-of-life 1, 2 and 5 year postoperatively and function (Constant-Murley score, glenohumeral range of motion), recovery status, pain (visual analogue scale), economic evaluation, satisfaction of treatment on the short-term and long-term and re-tear rate at 6 months determined with an ultrasound., Ethics and Dissemination: This trial has been approved by the Medical Research Ethics Committees United (MEC-U), Nieuwegein, the Netherlands (NL54313.100.15) and will be performed in accordance with the Declaration of Helsinki with the Medical Research Involving Human Subjects Act (WMO). The results of this study will be reported in peer-reviewed journals and at (inter)national conferences. Furthermore, we will share our findings with the appropriate guideline committees., Trial Registration Number: The Dutch Trial Registry (NL4010)., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Fatty infiltration is an important prognostic factor for cuff healing after rotator cuff repair. Treatment options for stage 2-3 Goutallier rotator cuff tears vary widely and there is lack of decent comparative studies., Purposes: The objective of this study was 1) to give an overview of the treatment options of stage 2-3 Goutallier rotator cuff tears and their clinical outcome and 2) to give a recommendation of the optimal treatment within this specific subgroup., Methods: We searched the databases of Medline, Embase, Cochrane library, NHS Centre for Reviews and Dissemination, PEDro from inception to December 12th, 2016. Two authors, F.H. and N.W., selected the studies after consensus. Data was extracted by one author (F.H.) and checked for completeness by a second author (N.W.). Our primary outcome was physical function, measured by shoulder-specific patient reported outcomes. Secondary outcomes were cuff integrity after rotator cuff repair, shoulder pain, general health, quality of life, activity level and adverse events., Results: For the first research question 28 prospective as well as retrospective studies were included. For the clinical outcome of these treatments three randomized controlled trials were included., Conclusions: Despite the high reported retear rate, rotator cuff repair has comparable results (clinical improvement) as partial repair and isolated bicepstenotomy or tenodesis. These findings suggest that the additional effect of rotator cuff repair compared to the less extensive treatment options like isolated bicepstenotomy or tenodesis should be studied, as these might form a good alternative treatment based on this systematic review., Level of Evidence: Level IV; systematic review.

Purpose: To study the effects on pain as the main outcome parameter and on function and cuff integrity as the secondary outcome parameters after arthroscopic rotator cuff repair in the short term comparing the abduction brace with an antirotation sling for postoperative shoulder immobilization., Methods: Eligible patients were between the ages of 18 and 75 years who were diagnosed with a traumatic or degenerative tear of the supraspinatus and/or infraspinatus tendon, confirmed by magnetic resonance imaging, for which an arthroscopic footprint repair was indicated and performed. Patients were randomly allocated to the antirotation sling or abduction brace group. Postoperative pain and use of analgesics were accurately registered up to 3 months after surgery using a patient diary. Follow-up examinations including the Constant-Murley score, Western Ontario Rotator Cuff index, and glenohumeral range of motion were scheduled 6 weeks, 3 and 6 months, and 1 year after surgery., Results: The average level of pain measured directly postoperation up to 1 year after surgery was not significant different between groups. Postoperatively, function scores and glenohumeral range of motion improved significantly for both groups; however, no differences were observed between groups. No retears were observed on ultrasonograph 3 months after surgery., Conclusions: In the short term, the level of pain, function, and quality of life were not significantly different between the use of an abduction brace and that of an antirotation sling after arthroscopic rotator cuff repair. Based on these findings, the abduction brace used in this study does not seem to be the solution for decreasing the pain experienced in the first postoperative weeks after arthroscopic rotator cuff repair, and both are recommendable., Level of Evidence: Level I, randomized controlled trial., (Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Hypothesis: This study determined the response shift in patients undergoing rotator cuff repair using the Western Ontario Rotator Cuff index (WORC), a disease-specific quality of life questionnaire. We hypothesized there would be a response shift with a positive recalibration (overestimated their preoperative disability) on the WORC and increases over time., Methods: The study prospectively included 36 patients undergoing arthroscopic rotator cuff repair. At baseline, 3 months (T1), and 1 year (T2) after surgery the WORC, EuroQol (EQ)-5D-3L, and the patient's level of satisfaction after surgery were scored. To evaluate the response shift, patients also completed the WORC at 3 months (Pre-T1) and 1 year (Pre-T2) as how they perceived themselves to have been before surgery., Results: The result on Pre-T1 and Pre-T2 results revealed that patients retrospectively rated their overall WORC score comparable with the baseline WORC score (Pre-T0; T0 = 40.5 ± 18.4, Pre-T1 = 45.0 ± 22.7, Pre-T2 = 34.3 ± 21.3). No response shift was observed on all domains except a negative recalibrated response shift for emotional disability on T1 (P = .04)., Conclusions: No significant group-level response shift was observed using the WORC, except for the subdomain emotional disability at 3 months after arthroscopic rotator cuff repair. With the absence of any shift in patient's perception on the self-administered quality of life-related WORC questionnaire, this study suggests one could retrospectively reliably conduct group-level preoperative baseline information on quality of life up to 1 year after surgery., (Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Postoperative urinary retention is a common complication after major orthopedic procedures of the lower limb. In total hip arthroplasty and total knee arthroplasty, the incidence ranges from 7% to 84%. In this study, the incidence and risk factors for postoperative urinary retention were described in a cohort of 376 men undergoing total hip arthroplasty. Postoperative urinary retention was defined as the inability to void after surgery for which single or indwelling catheterization was performed. Risk factors were identified using multivariate regression analysis. Following total hip arthroplasty, 150 (39.9%) of the 376 men developed urinary retention. Patient-controlled analgesia (odds ratio, 4.10; 95% confidence interval, 1.79-9.40), use of spinal anesthesia (odds ratio, 1.79; 95% confidence interval, 1.07-2.99), and age 70 years or older (odds ratio, 1.77; 95% confidence interval, 1.06-2.95) were independent risk factors for urinary retention. Potential risk factors that were not confirmed included body mass index, American Society of Anesthesiologists physical status (Class I-III), hypertension, diabetes mellitus, prostate pathology, smoking, average pain during the first 24 hours after surgery, and length of surgery. Two of the 150 patients with urinary retention (1.3%) for which a catheter has been inserted developed a urinary tract infection vs none of the patients without urinary retention. The risk of urinary retention after total hip arthroplasty is increased in men older than 70 years, those receiving spinal anesthesia, and those with patient-controlled analgesia postoperatively., (Copyright 2015, SLACK Incorporated.)