bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional Flexion Instability After Rotating-Platform Total Knee Arthroplasty
Authors: Quinlan Nicole Durig , Wu Yongren , Chiaramonti Alexander M. , Guess Sarah , Barfield William R. , Yao Hai , Pellegrini Vincent D. 
Published: August 2020

Background:
We sought to define “at risk” loading conditions associated with rotating-platform total knee arthroplasty (TKA-RP) implants that predispose to insert subluxation and spinout and to quantify tolerances for flexion-extension gap asymmetry and laxity in order to prevent these adverse events.

Methods:
Biomechanical testing was performed on 6 fresh-frozen cadaveric limbs with a TKA-RP implant with use of a gap-balancing technique, followed by sequential femoral component revision with variable-thickness polyethylene inserts to systematically represent 5 flexion-extension mismatch and asymmetry conditions. Each configuration was subjected to mechanical loading at 0°, 30°, and 60°. Rotational displacement of the insert on the tibial baseplate, lateral compartment separation, and insert concavity depth were measured with use of a digital caliper. Yield torque, a surrogate for ease of insert rotation and escape of the femoral component, was calculated with use of custom MATLAB code.

Results:
Design-intended insert rotation decreased with increasing knee flexion angles in each loading configuration. Likewise, yield torque increased with increasing joint flexion and decreased with increasing joint laxity in all testing configurations. Insert instability and femoral condyle displacement were reproduced in positions of increasing knee flexion and asymmetrical flexion gap laxity. The depth of lateral polyethylene insert concavity determined femoral condylar capture and defined a narrow tolerance of <2 mm in the smallest implant sizes for flexion gap asymmetry leading to rotational insert instability.

Conclusions:
Decreased femoral-tibial articular surface conformity with increasing knee flexion and asymmetrical flexion gap laxity enable paradoxical motion of the femoral component on the upper insert surface rather than the undersurface, as designed.

Clinical Relevance:
Mobile-bearing TKA-RP is a technically demanding procedure requiring a snug symmetrical flexion gap. As little as 2 mm of asymmetrical lateral flexion laxity can result in decreased conformity, condyle liftoff, and insert subluxation. Flexion beyond 30° decreases bearing surface contact area and predisposes to reduced insert rotation and mechanical malfunction.
Revision Following Cemented and Uncemented Oxford-III Primary Medial Unicompartmental Knee Replacements
Authors: Gupta Vikesh , Kejriwal Ritwik , Frampton Chris 
Published: August 2020

Background:
Oxford-III unicompartmental knee replacements (UKRs) are among the most commonly used prostheses to treat isolated medial compartment osteoarthritis (OA). However, the best mode of implant fixation for primary UKRs remains a source of debate. The hypothesis of this study was that the biologically superior fixation of uncemented Oxford-III primary UKRs would translate into a lower revision rate when compared with cemented Oxford-III primary UKRs used to treat isolated medial compartment OA.

Methods:
Data on all Oxford-III primary UKRs (n = 8,733) completed for isolated medial compartment OA from January 2000 to December 2018 were obtained from the New Zealand Joint Registry (NZJR). Revision rates were documented for each fixation type and analyzed for associations with patient sex and age at surgery. A multivariate Cox proportional-hazards analysis was completed to determine if type of fixation was an independent risk factor for revision of Oxford-III UKRs.

Results:
Statistical analysis revealed a >1.8-fold greater revision risk for cemented Oxford-III UKRs compared with uncemented Oxford-III UKRs (p = 0.001) when considered independently of other risk factors. Furthermore, compared with uncemented fixation, cemented fixation was associated with a 2.9-fold (p < 0.001) increase in revision risk for women <65 years old and a 1.7-fold (p = 0.008) increase in revision risk for men 55 to 74 years old. There was no significant difference in the risk of revision between fixation methods for women ≥65 years old and men ≥75 years old.

Conclusions:
We found that the type of fixation was an independent risk factor for revision of Oxford-III UKRs used in the treatment of isolated medial compartment OA. Uncemented Oxford-III primary UKRs had superior implant survivorship in women <65 years old and men 55 to 74 years old. Age and sex are important factors to consider when determining the type of fixation for Oxford-III primary UKRs used to treat isolated medial compartment OA.

Level of Evidence:
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Function-Sparing Free Split Latissimus Dorsi Flap for Lower-Extremity Reconstruction
Authors: Chim Harvey , Cohen-Shohet Rachel , McLaughlin Mariel M. , Ehanire Tosan 
Published: August 2020

Background:
The free split latissimus dorsi flap for lower-extremity reconstruction has some advantages over the traditional latissimus dorsi flap. The flap is harvested with the patient in the supine position and is associated with minimal morbidity as the function of the remaining latissimus dorsi muscle is preserved through the posterior division of the thoracodorsal nerve.

Methods:
A consecutive single-surgeon 5-year series of free split latissimus dorsi muscle flaps for lower-extremity reconstruction (n = 42) was evaluated. Donor site morbidity was evaluated through assessment of the strength of the remaining latissimus dorsi at least 1 month after surgery. Shoulder function was evaluated postoperatively using the Disabilities of the Arm, Shoulder and Hand (DASH) score, American Shoulder and Elbow Surgeons (ASES) score, and Shoulder Pain and Disability Index (SPADI).

Results:
The mean age of the 42 patients was 40.7 years. The mean length and width of the flaps were 17.9 cm and 8.6 cm. The majority (71%) of the wounds were due to acute trauma. Of the 42 flap procedures performed, 95% (40) were successful. Assessment of remaining latissimus dorsi strength at least 1 month postoperatively, during 3 activities, showed a Medical Research Council (MRC) grade of 5 in all patients. The mean and median scores were 6.4 and 0 according to the DASH, 6.0/6.4 and 0/0 on the SPADI pain/disability scales, and 90.7 and 100 on the ASES.

Conclusions:
The free split latissimus dorsi flap is a large reliable muscle flap with negligible donor site morbidity that is particularly advantageous for lower-extremity resurfacing following trauma.

Level of Evidence:
Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Timing of Antimicrobial Prophylaxis and Tourniquet Inflation
Authors: Hanberg Pelle , Bue Mats , Öbrink-Hansen Kristina , Thomassen Maja , Søballe Kjeld , Stilling Maiken 
Published: August 2020

Background:
Tourniquets are widely used during extremity surgery. In order to prevent surgical site infection, correct timing of antimicrobial prophylaxis and tourniquet inflation is important. We aimed to evaluate the time for which the free drug concentration of cefuroxime is maintained above the minimum inhibitory concentration (t > MIC) in porcine subcutaneous adipose tissue and calcaneal cancellous bone during 3 clinically relevant tourniquet application scenarios.

Methods:
Twenty-four female Danish Landrace pigs were included. Microdialysis catheters were placed bilaterally for sampling of cefuroxime concentrations in calcaneal cancellous bone and subcutaneous adipose tissue, and a tourniquet was applied to a randomly picked leg of each pig. Subsequently, the pigs were randomized into 3 groups to receive 1.5 g of cefuroxime by intravenous injection 15 minutes prior to tourniquet inflation (Group A), 45 minutes prior to tourniquet inflation (Group B), and at the time of tourniquet release (Group C). The tourniquet duration was 90 minutes in all groups. Dialysates and venous blood samples were collected for 8 hours after cefuroxime administration. Cefuroxime and various ischemic marker concentrations were quantified.

Results:
Cefuroxime concentrations were maintained above the clinical breakpoint MIC for Staphylococcus aureus (4 µg/mL) in calcaneal cancellous bone and subcutaneous adipose tissue throughout the 90-minute tourniquet duration in Groups A and B. Cefuroxime administration at the time of tourniquet release (Group C) resulted in concentrations of >4 µg/mL for approximately of 3.5 hours in the tissues on the tourniquet side. Furthermore, tourniquet application induced ischemia (increased lactate:pyruvate ratio) and cell damage (increased glycerol) in subcutaneous adipose tissue and calcaneal cancellous bone. Tissue ischemia was sustained for 2.5 hours after tourniquet release in calcaneal cancellous bone.

Conclusions:
Administration of cefuroxime (1.5 g) in the 15 to 45-minute window prior to tourniquet inflation resulted in sufficient concentrations in calcaneal cancellous bone and subcutaneous adipose tissue throughout the 90-minute tourniquet application. Furthermore, tourniquet-induced tissue ischemia fully resolved 2.5 hours after tourniquet release.

Clinical Relevance:
Cefuroxime administration 15 to 45 minutes prior to tourniquet inflation seems to be a safe window. If the goal is to maintain postoperative cefuroxime concentrations above relevant MIC values, our results suggest that a second dose of cefuroxime should be administered at the time of tourniquet release.
Hip Muscle Forces and Contact Loading During Squatting After Cam-Type FAI Surgery
Authors: Catelli Danilo S. , Ng K.C. Geoffrey , Wesseling Mariska , Kowalski Erik , Jonkers Ilse , Beaulé Paul E. , Lamontagne Mario 
Published: August 2020

Background:The purpose of this study was to compare muscle forces and hip contact forces (HCFs) during squatting in patients with cam-type femoroacetabular impingement (cam-FAI) before and after hip corrective surgery and with healthy control participants.Methods:Ten symptomatic male patients with cam-FAI performed deep squatting preoperatively and at 2 years postoperatively. Patients were matched by age and body mass index to 10 male control participants. Full-body kinematics and kinetics were computed, and muscle forces and HCFs were estimated using a musculoskeletal model and static optimization. Normalized squat cycle (%SC) trials were compared using statistical nonparametric mapping (SnPM).Results:Postoperatively, patients with cam-FAI squatted down with higher anterior pelvic tilt, higher hip flexion, and greater hip extension moments than preoperatively. Preoperative patients demonstrated lower anterior pelvic tilt and lower hip flexion compared with the participants in the control group. Postoperative patients showed increased semimembranosus force compared with their preoperative values. Preoperative forces were lower than the control group for the adductor magnus, the psoas major, and the semimembranosus; however, the preoperative patients showed greater inferior gluteus maximus forces than the patients in the control group, whereas the postoperative patients did not differ from the control patients. Higher posterior, superior, and resultant HCF magnitudes were identified postoperatively in comparison with the preoperative values. Preoperative posterior HCF was lower than in the control group, whereas the postoperative posterior HCF did not differ from those in the control group.Conclusions:Higher postoperative anterior pelvic tilt was associated with an indication of return to closer to normal pelvic motion, which resembled data from the control group. Lower preoperative anterior pelvic tilt was associated with muscle force imbalance, indicated by decreased semimembranosus and increased gluteus maximus forces. The overall increased postoperative muscle forces were associated with improved pelvic mobility and increased HCFs that were comparable with the control-group standards.Clinical Relevance:Muscle forces and HCFs may be indicative of postoperative joint health restoration and alleviated symptoms.
Safety of Single-Stage Bilateral Versus Unilateral Anterior Total Hip Arthroplasty
Authors: Vanbiervliet Jens , Dobransky Johanna , Poitras Stéphane , Beaulé Paul E. 
Published: August 2020

Background:
Limited data exist on patient safety after single-stage bilateral and unilateral total hip arthroplasty (THA) through the anterior approach (AA). Therefore, the aim of this study was to compare length of stay (LOS), operative time, 90-day adverse events, 90-day readmission rate, and 1-year revision rate after single-stage bilateral and unilateral THA in matched patients.

Methods:
This was a retrospective matched cohort study of prospectively collected data from 2008 to 2018 of a single-surgeon practice. We used the built-in propensity score matching formula in SPSS software and matched bilateral and unilateral patient groups on the relevant covariates of age, sex, and body mass index. This resulted in 60 patients undergoing bilateral THA and 60 patients undergoing unilateral THA.

Results:
The average LOS was 4.7 days (interquartile range [IQR], 3 to 5 days; range, 2 to 21 days) after bilateral THA and 3.0 days (IQR, 2 to 4 days; range, 1 to 13 days) after unilateral THA (p < 0.001). The mean operative time was 140 minutes for bilateral THA and 69 minutes for unilateral THA (p < 0.001). The adverse event rate was 6.7% after bilateral THA and 5.0% after unilateral THA (p = 0.660). The 90-day readmission rate was 3.3% after bilateral THA and 5.0% after unilateral THA (p = 0.321), which also accounted for all of the revisions within the first year.

Conclusions:
When considering single-stage versus staged bilateral AA total hip replacement, patients can expect the same clinical outcome. Because the operative time is longer with bilateral THA, the main advantages are that the patient avoids a second anesthesia session and has an overall shorter recovery time.

Level of Evidence:
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Surgical Interventions for Cervical Radiculopathy without Myelopathy
Authors: Broekema Anne E.H. , Groen Rob J.M. , Simões de Souza Nádia F. , Smidt Nynke , Reneman Michiel F. , Soer Remko , Kuijlen Jos M.A. 
Published: August 2020

Background:
The effectiveness of surgical interventions for cervical degenerative disorders has been investigated in multiple systematic reviews. Differences in study population (e.g., patients with myelopathy and/or radiculopathy) were often neglected. Therefore, the objective of this study was to investigate the effectiveness of surgical interventions for patients with symptoms of cervical radiculopathy without myelopathy by conducting a systematic review and meta-analysis based on randomized controlled trials (RCTs).

Methods:
A comprehensive systematic search was conducted in MEDLINE, Embase, and CENTRAL (Cochrane Central Register of Controlled Trials) to identify RCTs that investigated the effectiveness of surgical interventions using an anterior or posterior approach compared with other interventions for patients with pure cervical radiculopathy. Outcomes were success rates (Odom criteria, similar rating scales, or percentage of patients who improved), complication and reoperation rates, work status, disability (Neck Disability Index), and pain (arm and neck). The Cochrane risk-of-bias tool was used to assess the likelihood of the risk of bias. A random-effects model was used. Heterogeneity among study results (I
2
≥ 50% or p < 0.05) was explored by conducting subgroup analyses. Funnel plots were used to assess the likelihood of publication bias.

Results:
A total of 21 RCTs were included, comprising 1,567 patients. For all outcomes, among all surgical techniques, only 1 pooled estimate showed a significant effect on success rate, which was in favor of anterior cervical discectomy with fusion compared with anterior cervical discectomy without an intervertebral spacer (p = 0.02; risk ratio [RR] = 0.87; 95% confidence interval [CI] = 0.77 to 0.98). Complication rates were higher when autologous bone graft from the iliac crest was used as an intervertebral spacer (p < 0.01; RR = 3.40; 95% CI = 1.56 to 7.43), related to donor-site morbidity.

Conclusions:
This meta-analysis demonstrated consistent results regarding clinical outcome for pure cervical radiculopathy among all studied interventions. Complication and reoperation rates were also similar, with the exception of higher complication rates in patients in whom autologous bone grafts were used. On the basis of clinical outcome and safety, there is no superior surgical intervention for pure cervical radiculopathy.

Level of Evidence:
Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.
Needs assessment for a curriculum for difficult conversations -A survey from 5 Chinese accredited neurology residency training programs
Authors: Zhou Lixin , Wu Bo , Wu Liyong , Cheng Xin , Hu Bo , Yao Ming , Zhu Yicheng , Peng Bin , Cui Liying , Ni Jun 
Published: August 2020

Abstract
Background: Communication skill is a core competency in neurology residency training. Specific training in this area at the residency level is often lacking, especially regarding difficult conversations. The aim of this study is to evaluate the current state in teaching residents about difficult conversations in 5 Chinese accredited neurology residency training programs and determine whether there is a perceived need for a formalized curriculum in this field.Methods: An anonymous, 27-question, cross-sectional online survey addressing difficult conversations for neurological residents were distributed to five grade-A, class-3 hospitals selected from the affiliated teaching hospitals of medical schools qualified to provide neurology residency training in China.Results: A total of 182 residents responded to the survey, and the response rate was 67.16% (182/271). Of the participants, 84.6% were female and the average age was 26.8 years. The majority of respondent residents (n=168; 92.31%) reported being exposed to at least one difficult conversation in their medical careers. Only 43 (23.63%) participants reported having previously received formal communication skills training. In comparison with residents without previous training, those with previous training indicated significantly more confidence（P=0.003）and were under lower pressure（P=0.037）in managing difficult conversations. Only 97 (53.3%) residents indicated interest in receiving formal training. Time, lack of enthusiasm, lack of educational materials and faculty expertise were commonly cited barriers to formalized training.Conclusion: This survey provides a preliminary assessment of the current status of education on the topic of difficult conversations in five accredited Chinese neurology residency training programs. Our results suggest that there is an unmet need to further develop and implement educational activities by teaching residents to lead difficult conversations. Future efforts should be made to establish and promote a standard and targeted communication curriculum in difficult conversation for Chinese neurological residents.
14-type HPV mRNA test in triage of HPV DNA positive postmenopausal women with normal cytology
Authors: Asciutto Katrin Christine , Borgfeldt Christer , Forslund Ola 
Published: August 2020

Abstract
Background: During 2013 and 2016 the Region of Skåne, Sweden, started to analyse human papillomavirus (HPV) and cytology in postmenopausal women 60-65 years of age. Our aim was to evaluate high-risk (HR) HPV mRNA testing for the triage of HPV DNA positive postmenopausal women with normal cytology.Methods: A total of 271 women, 60-65 years of age, underwent liquid based cytology (LBC) and HPV testing by using the HR-HPV DNA MGP-PCR-Luminex assay. HR-HPV DNA-positive women with normal cytology underwent complimentary HPV mRNA testing (Aptima, Hologic Inc.). Over a period of 49 months (SD 11.0) the women received regular follow-up at intervals of 12-18 months. Women with abnormal cytology and/or a positive HR-HPV DNA and/or mRNA result at two subsequent visits were scheduled for colposcopy and clinical examination. Results: Over the surveillance period, 3.6% (10/271) of the HR-HPV DNA positive women developed histologically confirmed high-grade squamous intraepithelial lesions (HSILs) or worse. The cumulative incidence rates (CIR) were 29.7% (CI 24.8-30.1) for HSIL or worse among HPV mRNA-positive women at enrolment (39.5% 107/271) and 0% among HPV mRNA negative women (60.5%, 164/271), (p=0.002). Conclusions: Postmenopausal women with normal cytology along with the presence of HR-HPV mRNA are at increased risk for development of severe cervical dysplasia, in contrast to those women with negative HR-HPV mRNA. The HR-HPV mRNA APTIMA assay detecting 14 HR-HPV types may be a useful triage method among HPV DNA positive postmenopausal women with normal cytology.
Inhibitory effects of iron depletion plus eribulin on the breast cancer microenvironment
Authors: Goto Wataru , Kashiwagi Shinichiro , Asano Yuka , Takada Koji , Morisaki Tamami , Takahashi Katsuyuki , Fujita Hisakazu , Shibutani Masatsune , Amano Ryosuke , Takashima Tsutomu , Tomita Shuhei , Hirakawa Kosei , Ohira Masaichi 
Published: August 2020

Abstract
Background: Iron is required for the proliferation of cancer cells, and its depletion suppresses tumor growth. Eribulin mesylate (eribulin), a non-taxane microtubule inhibitor, disrupts the tumor microenvironment via vascular remodeling and obstruction of the epithelial-mesenchymal transition (EMT). Herein, we investigated the effects of the iron chelator on tumor-related properties of breast cancer cells and the effects of iron chelator plus eribulin on tumor growth in vivo.Methods: Two triple-negative breast cancer (TNBC) cell lines, MDA-MB-231 and BT-549, and one hormone-receptor positive breast cancer cell line, MCF-7, were used in our study. Cell proliferation, cell migration, cell cycle position, and gene expression were analyzed via MTT assays, wound-healing assays, flow cytometry, and quantitative real-time-polymerase chain reaction, respectively. For the in vivo experiments, mice with breast cancer xenografts were treated with the inhibitors, alone or together, and tumor volume was determined.Results: Iron chelator inhibited breast cancer cell proliferation and decreased the proportion of S-phase cells. Conversely, it induced hypoxia, angiogenesis, EMT, and immune checkpoints, as determined by quantifying the expression of marker mRNAs in MDA-MB-231 and MCF-7 cells. Eribulin suppressed the expression of the hypoxia and EMT related marker mRNAs in the presence of iron chelator. Iron chelator plus eribulin inhibited tumor growth in vivo to a greater extent than did either inhibitor alone.Conclusions: Although iron chelator induces oncogenic events (hypoxia, angiogenesis, EMT, and immune checkpoints), it may be an effective treatment for breast cancer when administered in combination with eribulin.