Search

Hip and knee biomechanics measured during a drop vertical jump (DVJ) can be used to assess patients undergoing rehabilitation after anterior cruciate ligament (ACL) reconstruction. To confidently interpret such data for use as outcome measures, additional information about reliability and validity is required. Therefore, the objective of this study was to estimate the test-retest reliability and longitudinal validity of selected lower limb biomechanics assessed during a DVJ in patients undergoing rehabilitation after ACL reconstruction. Biomechanical analysis of the DVJ in primary unilateral ACL reconstruction patients (22.3 ± 5.5y) were tested twice within 1 week at 6 months post-surgery (n = 46), and again at 12 months post-surgery (n = 36). Peak and initial contact knee angles and moments, hip impulse, vertical ground reaction forces (VGRF), isokinetic knee extension and flexion strength, and global ratings of change (GRC) were assessed. Reliability was evaluated based on the 6-month post-surgery data using intraclass correlation coefficients (ICC 2,1 ), standard errors of measurement and minimum detectable change. Longitudinal validity was evaluated by assessing change from 6 to 12 months, using standardized response means (SRM), and by assessing the correlation (Pearson's r) of change in landing biomechanics with change in strength, and GRC. ICCs ranged from 0.58 to 0.90 for peak knee abduction and flexion moments, 0.44-0.85 for knee flexion and abduction angles, 0.82-0.93 for VGRFs, and 0.42-0.65 for hip impulse. SRMs and correlations of change ranged from 0.00 to 0.50. Reliability and longitudinal validity of DVJ measures varied, ranging from poor-to-excellent; the present results assist in their interpretation when assessed during rehabilitation after ACL reconstruction., 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 © 2024. Published by Elsevier Ltd.)

Objective: Operating room (OR) fires are considered "never events," but approximately 650 events occur annually in the United States. Our aim was to detail fires occurring during orthopedic procedures via a questionnaire because of the limited information present on this topic., Methods: A 25-question survey on witnessing surgical fires, hospital policies on surgical fires, and surgeons' perspective on OR fires was sent to 617 orthopedic surgeons in 18 institutions whose residency program is a member of the Collaborative Orthopaedic Educational Research Group. The response rate was 28%, with 172 surgeons having completed the survey., Results: Twelve of the 172 orthopedic surgeons surveyed reported witnessing at least 1 surgical fire in an OR setting. Electrocautery was the leading ignition source, causing fires in 7 events. A saw, laser, and light source were reported to have caused 1 fire each. Regarding fuel source for the fires, bone cement was a common culprit (n = 4), followed by gauze (n = 3). Oxygen delivery to patients was via a closed system in most cases (n = 9). No patient harm was reported in any of these cases.Just under half of the respondents (47.7%) reported not receiving any formal OR fire prevention or response training. The most common answer for frequency of concern about a surgical fire was "never" (42.4%)., Conclusions: Fires pose a risk in surgery, even in an orthopedics setting. Room oxygen can supply enough oxidizing power for a fire to occur, especially with the ubiquitous nature of ignition sources and fuels in the OR. Prevention is key with these events. Operating room personnel education must be sought, and surgeons should be mindful of the fire components in the OR., Competing Interests: B.A.P. holds stock or stock options in Help Lightning; is paid consultant and paid presenter or speaker of Tornier; and holds IP royalties in Wright Medical Technology, Inc. S.G. is a board or committee member of the American Academy of Orthopedic Surgeons Pediatric Orthopaedic Society of North America and the Alabama Orthopaedic Society. M.B. is a board or committee member of the AAOS and the American Orthopaedic Association; holds IP royalties in, is a paid consultant for, and received research support from Medacta; receives research support from the National Institutes of Health (National Institute of Arthritis and Musculoskeletal and Skin Diseases National Institute of Child Health and Human Development), Zimmer, Stryker, and Mako Surgical; and a paid consultant of Zimmer. J.W. is a board or committee member of the American Orthopaedic Association and a paid consultant of T&T Clinical Research Consulting. M.D.W. is a board or committee member of the AAOS, Alumni Association School of Medicine of Loma Linda University, Health Services International, and Neufeld Society (Alumni Association) and is a part of editorial or governing board of the Clinical Orthopaedics and Related Research. M.J. is a paid consultant of in2bones and ODI and receives research support from the Small Bone Innovations. M.K. is a board or committee member of AOTrauma. J.B.J. is a board or committee member of the AAOS and American Orthopaedic Foot and Ankle Society. J.M.S. receives research support from Aesculap/B. Braun. W.K.P. is part of editorial or governing board of the Journal of Bone & Joint Surgery–American. B.M. is a board or committee member of the Indiana Orthopaedic Society and the Orthopaedic Trauma Association and is a paid consultant of Kidde Consultants Inc. S.T.G. is a board or committee member of the AAOS, Michigan Orthopaedic Society, and Mid-America Orthopaedic Association. A.K.S. is a paid presenter or speaker of Globus Medical and Synthes and holds stock or stock options in Zimmer, and she and her husband are employees of Zimmer. C.J.G. is part of editorial or governing board of the American Journal of Sports Medicine, Clinical Orthopaedics and Related Research, and Journal of Bone & Joint Surgery–American; is paid consultant and paid presenter or speaker of and receives research support from the Musculoskeletal Transplant Foundation; and holds stock or stock options in Novopedics. A.R. is a board or committee member of the AAOS, American Orthopaedic Association, Clinical Orthopaedic Society, and New York State Orthopaedic Society. The other authors disclose no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

In women with placenta accreta spectrum (PAS), patient management may involve cesarean hysterectomy at delivery. Magnetic resonance imaging (MRI) has been used for further evaluation of PAS and surgical planning. This work tackles two prediction problems: predicting presence of PAS and predicting hysterectomy using MR images of pregnant patients. First, we extracted approximately 2,500 radiomic features from MR images with two regions of interest: the placenta and the uterus. In addition to analyzing two regions of interest, we dilated the placenta and uterus masks by 5, 10, 15, and 20 mm to gain insights from the myometrium, where the uterus and placenta overlap in the case of PAS. This study cohort includes 241 pregnant women. Of these women, 89 underwent hysterectomy while 152 did not; 141 with suspected PAS, and 100 without suspected PAS. We obtained an accuracy of 0.88 for predicting hysterectomy and an accuracy of 0.92 for classifying suspected PAS. The radiomic analysis tool is further validated, it can be useful for aiding clinicians in decision making on the care of pregnant women.

Hyperspectral imaging (HSI) and radiomics have the potential to improve the accuracy of tumor malignancy prediction and assessment. In this work, we extracted radiomic features of fresh surgical papillary thyroid carcinoma (PTC) specimen that were imaged with HSI. A total of 107 unique radiomic features were extracted. This study includes 72 ex-vivo tissue specimens from 44 patients with pathology-confirmed PTC. With the dilated hyperspectral images, the shape feature of least axis length was able to predict the tumor aggressiveness with a high accuracy. The HSI-based radiomic method may provide a useful tool to aid oncologists in determining tumors with intermediate to high risk and in clinical decision making.

In severe cases, placenta accreta spectrum (PAS) requires emergency hysterectomy, endangering the life of both mother and fetus. Early prediction may reduce complications and aid in management decisions in these high-risk pregnancies. In this work, we developed a novel convolutional network architecture to combine MRI volumes, radiomic features, and custom feature maps to predict PAS severe enough to result in hysterectomy after fetal delivery in pregnant women. We trained, optimized, and evaluated the networks using data from 241 patients, in groups of 157, 24, and 60 for training, validation, and testing, respectively. We found the network using all three paths produced the best performance, with an AUC of 87.8, accuracy 83.3%, sensitivity of 85.0, and specificity of 82.5. This deep learning algorithm, deployed in clinical settings, may identify women at risk before birth, resulting in improved patient outcomes., Competing Interests: DISCLOSURE The authors have no relevant financial interests in this article and no potential conflicts of interest to disclose.

Objective: To test the hypothesis that higher walking cadence is associated with lower knee loading, while controlling for walking speed, in patients with medial compartment tibiofemoral osteoarthritis (OA)., Methods: A total of 691 patients underwent quantitative gait analysis, including 3-dimensional knee moments and temporospatial parameters. Using multivariate linear regression, we tested the association of walking cadence with the knee adduction moment angular impulse (a surrogate measure of medial knee compartment load throughout the stance), while controlling for walking speed. We repeated the analysis while also adjusting for sex, age, body mass index, radiographic OA, knee pain, lateral trunk lean, foot progression angle, and mechanical axis angle, and while replacing the knee adduction moment angular impulse with other surrogate measures of knee loading., Results: While controlling for walking speed, we found that a lower cadence was associated with higher knee adduction moment angular impulse (standardized β = -0.396, P < 0.001), suggesting a 0.02% body weight × height × seconds (%BW × Ht × s) decrease in impulse for each step per minute increase in cadence (unstandardized β -0.020 %BW × Ht × s [95% confidence interval -0.027, -0.015]), and remained consistent after adjusting for covariates. A lower cadence was also associated with higher first (standardized β = -0.138, P = 0.010) and second peak knee adduction moment (standardized β = -0.132, P = 0.018), higher peak knee flexion moment (standardized β = -0.128, P = 0.049), and vertical ground reaction force (standardized β = -0.116, P = 0.035) in the adjusted analyses., Conclusion: When controlling for walking speed, we found that a lower cadence is associated with higher knee loading per step in patients with medial tibiofemoral OA. Future research should investigate the potential beneficial biomechanical and clinical effects of increasing walking cadence in patients with knee OA., (© 2020, American College of Rheumatology.)

The light-protective effectiveness of titanium dioxide polylactic acid (TiO 2 PLA) nanocomposite films (T-PLA) and oleic-acid-modified (OA&#95;TiO 2 PLA) nanocomposite films was investigated in ready-to-drink (RTD) green tea infusions in oxygen-impermeable glass packaging. The stability of (-)-epigallocatechin gallate (EGCG) was evaluated in RTD green tea infusions in glass packaging covered with PLA (polylactic acid), T-PLA and OT-PLA under fluorescent light during 20 days of storage at 4 °C. Levels of EGCG and color change of RTD green tea infusions were determined. In addition, sensory tests for difference were conducted on green tea infusions in glass packaging without and with complete light protection during 10 days of storage at 4 °C. Of the panelists, 60% noticed sensory differences in the RTD green tea infusion in two different packaging conditions during 10 days of storage under fluorescent light by a triangle test ( p < 0.05). During 20 days of storage, levels of EGCG with complete light protection decreased by 10.8% (0.73 mg/mL), and there was a 42.2% loss of EGCG (0.48 mg/mL) in RTD green tea infusions in the glass packaging covered by PLA film. Finally, 3% T-PLA preserved higher levels of EGCG in RTD green tea infusions compared to 1% T-PLA and OT-PLA.

To review and synthesize the biomechanical effects of valgus knee bracing for patients with medial knee osteoarthritis (OA). Electronic databases were searched from their inception to May 2014. Two reviewers independently determined study eligibility, rated study quality and extracted data. Where possible, data were combined into meta-analyses and pooled estimates with 95% confidence intervals (CI) for standardized mean differences (SMD) were calculated. Thirty studies were included with 478 subjects tested while using a valgus knee brace. Various biomechanical methods suggested valgus braces can decrease direct measures of medial knee compressive force, indirect measures representing the mediolateral distribution of load across the knee, quadriceps/hamstring and quadriceps/gastrocnemius co-contraction ratios, and increase medial joint space during gait. Meta-analysis from 17 studies suggested a statistically significant decrease in the external knee adduction moment (KAM) during walking, with a moderate-to-high effect size (SMD = 0.61; 95% CI: 0.39, 0.83; P < 0.001). Meta-regression identified a near-significant association for the KAM effect size and duration of brace use only (β, -0.01; 95% CI: -0.03, 0.0001; P = 0.06); with longer durations of brace use associated with smaller treatment effects. Minor complications were commonly reported during brace use and included slipping, discomfort and poor fit, blisters and skin irritation. Systematic review and meta-analysis suggests valgus knee braces can alter knee joint loads through a combination of mechanisms, with moderate-to-high effect sizes in biomechanical outcomes., (Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Objectives: (1) Test the hypothesis that walking poles decrease the external knee adduction moment during gait in patients with varus gonarthrosis, and (2) explore potential mechanisms., Design: Thirty-four patients with medial compartment knee osteoarthritis (OA) and varus alignment underwent three dimensional (3D) gait analysis with and without using walking poles. Conditions were randomized and walking speed was maintained ±5% of the self-selected speed of the initial condition. The pole held in the hand of the unaffected side was instrumented with a compression load cell., Results: Student's t tests for paired samples indicated small but statistically significant increases (P < 0.001) in knee adduction moment (calculated from inverse dynamics) for its first peak, second peak and angular impulse when using the poles; mean increases (95% confidence interval - CI) were 0.17%BW*Ht (0.08, 0.27), 0.17%BW*Ht (0.04, 0.30) and 0.15%BW*Ht*s (0.09, 0.22), respectively. There was a decrease (P = 0.015) in vertical ground reaction force (-0.02 BW (-0.04, -0.01)), yet increase (P < 0.001) in its frontal plane lever arm about the knee (0.30 cm (0.15, 0.44)), at the time of the first peak knee adduction moment. Pole force in the vertical direction was inversely related (r = -0.34, P = 0.05) to the increase in first peak adduction moment., Conclusion: Although results are variable among patients, and may be related to individual technique, these overall findings suggest that walking poles do not decrease knee adduction moments, and therefore likely do not decrease medial compartment loads, in patients with varus gonarthrosis. Decreases in knee joint loading should not be used as rationale for walking pole use in these patients., (Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

This retrospective study examined whether a delay of greater than 12 hours is associated with an increased risk of perioperative complications in the operative treatment of supracondylar humerus fractures in children. Of 150 consecutive children with supracondylar fractures, 50 underwent surgery in less than 12 hours and 100 underwent surgery greater than 12 hours after injury. There was no significant difference between groups in rate of open reduction (P = 0.55), pin tract infection (P = 1.0), iatrogenic nerve injury (P = 1.0), vascular complication (P = 0.33), or compartment syndrome (P = 1.0), including when Gartland type III fractures were analyzed independently. There was no iatrogenic nerve injury, no compartment syndrome, and one pin tract infection in 150 patients. The study confirms previous retrospective studies finding no significant difference in perioperative complications or rate of open reduction in children undergoing early versus delayed surgical treatment of supracondylar humerus fractures.

Background and Objectives: The purpose of this study was to compare the complications and functional outcome associated with the use of an irradiated allograft-implant composite or a bone-ingrowth modular tumor prosthesis for replacement of the knee joint after resection of a bone sarcoma from the distal femur or proximal tibia., Methods: Eleven patients initially received an allograft reconstruction, followed by 64 treated with a tumor prosthesis. The primary analysis concerned reconstructive failure, defined by the requirement for removal of the original construct. Functional outcome was assessed by using the 1987 Musculoskeletal Tumor Society rating system., Results: Reconstructive failure occurred in 6 of 11 (55%) allograft constructs compared with 10 of 64 (16%) tumor prostheses (P = 0.009). Failures were due to infection (2 of 11 allografts versus 4 of 64 prostheses; P = 0.2) or mechanical complications (4 of 11 allograft fractures versus 5 of 64 broken prosthetic stems and 1 aseptically loose prosthesis; P = 0.03). The limb salvage rate was 95% (61 of 64) for patients with a tumor prosthesis compared with 64% (7 of 11) for those with an allograft (P = 0.007). Patients with a tumor prosthesis had a better functional outcome with a mean score of 75% compared with 57% for those with an allograft reconstruction (P = 0.006)., Conclusions: This comparative study suggests that limb salvage surgery at the knee has a better and more predictable outcome with a tumor prosthesis than with an allograft-implant reconstruction., (Copyright 2001 Wiley-Liss, Inc.)

Hypothesis: Financial incentives are the only form of compensation that will motivate surgeons at an academic health sciences center to perform the tasks outlined in the hospital's mission statement., Design: A questionnaire divided into 5 sections: demographics, compensation, time allocation, benefits and incentives, and motivational factors., Setting: The Department of Surgery, The Toronto Hospital, Toronto, Ontario., Participants: All academic surgeons (N=64) practicing at The Toronto Hospital in July 1997., Results: Of the 64 eligible mailed surveys, there were responses for 59. Of these 59 surgeons, 48 (81%) receive compensation through a fee-for-service method. However, only 32 (54%) of the surgeons prefer the fee-for-service method, while 18 (31%) prefer salary and 9 (15%) prefer an alternative system. On average, these academic surgeons spend 44% of their time teaching or performing research, for which they receive 14% of their total income. Of the motivational factors assessed, financial bonuses are a positive motivational factor for all "surgeon tasks." In addition, task-specific motivational factors were established for research, teaching, and operating, including research facilities, mentorship and prestige, and interesting case types, respectively., Conclusions: Surgeons are not appropriately renumerated for time spent on academic activities, and many would prefer an alternative form of compensation to the fee-for-service method. Knowledge that surgeons are receptive to tasks supporting the hospital's mission statement leads us to conclude that appropriate motivation can shape the activity of academic surgeons. Financial rewards ranked the highest as a motivational factor for all surgeon tasks; however, task-specific motivational factors were identified. Overall, multiple factors, specifically targeted to the individual, will serve to motivate. Thus, compensation packages based on individual preferences and personal motivational factors will be the most successful.

The gel test, first reported in 1988, can be used for most areas of blood group serology, but this report deals specifically with ABO/Rh typing and antibody screening and investigation. The technique is simple and quick to perform and the reading of results is standardised and clean with no false-positive reactions being found in antiglobulin tests. Since gel anti-human globulin tests require no washing and the test cards may be sealed during centrifugation, the system is particularly advantageous for 'loosely bound' antibodies and 'high-risk' samples.

The study of domestic accidents, which includes accidents in and around the home and in institutions, is of increasing importance. The mortality statistics are shown in Table 1. In 1974, 18,335 people died from accidents in the UK (RoSPA, 1974) equivalent to the population of a reasonably sized town. Accidents form one of the four main causes of death in this country and have become relatively more common in recent years. Analysis of the causes of home accidents make it possible to plan ways of preventing them. General practitioners and their colleagues in the primary health care team have the principal responsibility.