The effect of COVID-19 on cancer incidences in the U.S

Fundamental data analysis assists in the evaluation of critical questions to discern essential facts and elicit formerly invisible evidence. In this article, we provide clarity into a subtle phenomenon observed in cancer incidences throughout the time of the COVID-19 pandemic. We analyzed the cancer incidence data from the American Cancer Society [1]. We partitioned the data into three groups: the pre-COVID-19 years (2017, 2018), during the COVID-19 years (2019, 2020, 2021), and the post-COVID-19 years (2022, 2023). In a novel manner, we applied principal components analysis (PCA), computed the angles between the cancer incidence vectors, and then added lognormal probability concepts in our analysis. Our analytic results revealed that the cancer incidences shifted within each era (pre, during, and post), with a meaningful change in the cancer incidences occurring in 2020, the peak of the COVID-19 era. We defined, computed, and interpreted the exceedance probability for a cancer type to have 1000 incidences in a future year among the breast, cervical, colorectal, uterine corpus, leukemia, lung & bronchus, melanoma, Hodgkin's lymphoma, prostate, and urinary cancers. We also defined, estimated, and illustrated indices for other cancer diagnoses from the vantage point of breast cancer in pre, during, and post-COVID-19 eras. The angle vectors post the COVID-19 were 72% less than pre-pandemic and 28% less than during the pandemic. The movement of cancer vectors was dynamic between these eras, and movement greatly differed by type of cancer. A trend chart of cervical cancer showed statistical anomalies in the years 2019 and 2021. Based on our findings, a few future research directions are pointed out.

Comparison of kinematics and electromyography in the last repetition during different maximum repetition sets in the barbell back squat

Background

The barbell squat is an exercise used to strengthen the lower limbs, with implications for both performance in sports and improving movement during everyday tasks. Although the exercise is being trained across a variety of repetition ranges, the technical requirements may vary, affecting appropriate repetition range for specific training goals.

Methods

A randomised within-subject design was used to compare kinematics and surface electromyography (EMG) in the lower extremities during different concentric phases (pre-, sticking- and post-sticking region) of the last repetition when performing squats at different repetition maximums (RMs). Thirteen strength-trained men (age: 23.6 ± 1.9 years; height: 181.1 ± 6.5 cm; body mass: 82.2 kg, 1RM: 122.8 ± 16.2, relative strength: 1.5 ± 0.2 x body mass in external load) performed a 1, 3, 6, and 10RM squat, in a randomised order.

Results

The main findings were that barbell-, ankle-, knee- and hip kinematics were similar across different repetition ranges, except for a smaller trunk lean at 1RM in the pre-sticking region compared to other repetitions and in the sticking region compared to 10RM (p ≤ 0.04). Furthermore, 1RM revealed significantly higher EMG amplitude in the vastus lateralis, gastrocnemius and soleus in the sticking and post-sticking regions when compared to 10RM. It was concluded that 10RM may locally fatigue the vastus lateralis and plantar flexors, explaining the lower EMG amplitude. The observed differences indicate that requirements vary for completing the final repetition of the 10RM compared to the 1RM, an important aspect to consider in training to enhance 1RM strength.

Sex-related differences in gait characteristics and their associations with symptoms in individuals with patellofemoral osteoarthritis

BACKGROUND

Patellofemoral osteoarthritis (OA) is an important subgroup of knee OA. However, the influence of sex on gait characteristics in patients with patellofemoral OA is unknown.

RESEARCH QUESTION

Compare gait characteristics in females and males with patellofemoral OA and investigate their associations with patellofemoral joint-related symptoms and limitations.

METHODS

Mixed effects polynomial regression models compared knee flexion-extension and adduction moments, knee flexion angles, and vertical ground reaction forces over 100% of stance between 26 females and 22 males with patellofemoral OA, with and without adjustment for walking speed and body mass. Multivariable linear regression models were then used to investigate the associations of gait characteristics with symptoms and limitations measured with the Knee injury and Osteoarthritis Outcome Score Patellofemoral Pain and Osteoarthritis (KOOS-PF) Subscale. Models included a sex-by-gait interaction term, and if significant, separate models were built for females and males.

RESULTS

While controlling for walking speed and body mass, females had lower knee flexion moment (6-19% and 97-100% of stance), knee extension moment (45-86% of stance), knee adduction moment (3-37% and 69-99% of stance), vertical ground reaction force (1-97% of stance) and knee flexion angle (90-100% of stance) compared with males, when fitted over 100% of stance. Lower cadence, lower knee flexion angular impulse, and higher peak knee flexion angle were associated with worse KOOS-PF scores. Associations were not modified by sex.

SIGNIFICANCE

There are distinct sex-based differences in gait characteristics throughout stance with patellofemoral OA when adjusting for body mass and walking speed. Lower cadence and knee flexion angular impulse, and higher peak knee flexion angle were associated with more extreme patellofemoral joint-related symptoms and limitations.

Effect of Rhinoplasty on Various Angles of Nose on Ideal Position and Alignment in Indian Population

Study of anthropometric measurements of the nose makes possible a qualitative and quantitative analysis of surgical results. Analysis of pre- and post-operative changes in nasal tip projection, rotation and nasofrontal angle may also emphasize the fact of over correction or under correction of deformed nose to surgeon. Aim of our study to compare preoperative and postoperative nasal tip projection, rotation and nasofrontal angle after rhinoplasty. The present study was a 1.5 years prospective interventional study conducted at SMS Medical College, Jaipur, India from January 2021 to July 2022. Total 51 patients with external nasal deformity were included in our study. Pre-operative, immediate post-operative and 6 months follow-up nasofrontal, projection and nasolabial angle were recorded, compared and analyzed objectively. In our study significant improvements were observed in the nasolabial angle from 92.9 ± 16.4 to 101.6 ± 10.4 and 110.3 ± 9.8 and nasal tip projection from 0.74 ± 0.17 to 0.58 ± 0.11 and 0.52 ± 0.09 immediate post-op and at 6-months follow up respectively. Mean Nasofrontal angle at pre-op, intra-op and post-op 6 months was 132.5 ± 11.9, 135.4 ± 9.6 and 134.8 ± 9.4 and this difference was not found to be statistically significant. We would like to conclude that Indian noses which are predominantly small and shorter, our surgical procedure aimed at making them more prominent aesthetically on the face, so in the present study results were satisfactory in term of anthropometric parameter.

The Spittlebug Mahanarva tristis as a Senior Synonymy of Four Neotropical Species of Mahanarva (Hemiptera: Auchenorrhyncha: Cercopidae), and Considerations About M. tristis Subspecies

Mahanarva Distant, the neotropical spittlebug genus contains 48 species and many of them are only known from their original descriptions and one location. A group of species of this genus stand out due to their similarities and are studied here. Based on comparisons between 28 Mahanarva tristis (Fabricius) specimens and the original drawings of the other species, we demonstrate strong morphological similarities. Examinations of the tegmina showed a polymorphism with different dot and stripe patterns. Those patterns are not exclusive for one species and are found throughout the taxa. Again, studying the male genitals no species-specific characters can be found. Furthermore, differences of the parameres were explained by different angle positions of these genital plates which alter the resulting photos and drawings significantly. On the other hand, changes of the aedeagus can be explained due to its fragile structure and the resulting manipulations during handling. In addition, the overlapping known distribution of the taxa leads to the conclusion that the four species are in fact synonyms of M. tristis and that there is no evidence for the validity of the subspecies. We conclude that the New World spittlebug M. tristis is considered a senior synonym of Mahanarva fraseri (Distant) n. syn., Mahanarva mura (China & Myers) n. syn., Mahanarva raripila (Jacobi) n. syn., and Mahanarva trifissa (Jacobi) n. syn. Aside from that, there was no evidence for the validity of the M. tristis subspecies Mahanarva tristis guppyi (Urich) n. syn., Mahanarva tristis monagasi (Fennah) n. syn., Mahanarva tristis quadrimaculata (Fennah) n. syn., Mahanarva tristis suffusa (Walker) n. syn., and Mahanarva tristis walkeri (Lallemand) n. syn. Unfortunately, it was not possible to conclude the taxonomic state of Mahanarva tristis stalii (Lallemand) because there are no known specimens or types available. So, the subspecies is considered a species inquirenda.

Comparison between Weightbearing-CT semiautomatic and manual measurements in Hallux Valgus

BACKGROUND

Radiographic measurements are an essential tool to determine the appropriate surgical treatment and outcome for Hallux Valgus (HV). HV deformity is best evaluated by weight-bearing computed tomography (WBCT). The objective was (1) to assess the reliability of WBCT computer-assisted semi-automatic imaging measurements in HV, (2) to compare semi-automatic with manual measurements in the setting of an HV, and (3) to compare semi-automatic measurements between HV and control group.

METHODS

In this retrospective IRB (ID# 201904825) approved study, we assessed patients with hallux valgus deformity. The sample size calculation was based on the hallux valgus angle (HVA). Thus to obtain the 0.8 power, including 26 feet with HV in this study, was necessary. Our control group consisted of 19 feet from 19 patients without HV. Raw multiplanar data was evaluated using software CubeVue®. In the axial plane, hallux valgus angle (HVA), intermetatarsal angle (IMA), and interphalangeal angle (IPA) were measured. The semiautomatic 3D measurements were performed using the Bonelogic®Software. Inter-rater reliabilities were performed using ICC. Agreement between methods was tested using the Bland-Altman plots. The difference between Patologic and Control cases using semi-automatic measurements was assessed with the Wilcoxon signed-rank test. Alpha risk was set to 5% (α = 0.05). P ≤ 0.05 were considered significant.

RESULTS

Reliabilities utilizing ICC were over 0.80 for WBCT manual measurements and WBCT semi-automatic readings. Inter and intraobserver agreement for Manual and Semi-automatic WBCT measurements demonstrated excellent reliability.

CONCLUSIONS

Semi-automatic measurements are reproducible and comparable to measurements performed manually. The software differentiated pathological from non-pathological conditions when subjected to semi-automatic measurements. The development of advanced semi-automatic segmentation software with minimal user intervention is essential for the establishment of big data and can be integrated into clinical practice, facilitating decision-making.

Preoperative calculation of angles of vision and working area in laparoscopic surgery to treat a giant hiatal hernia

BACKGROUND

Giant hiatal hernias still pose a major challenge to digestive surgeons, and their repair is sometimes a highly complex task. This is usually performed by laparoscopy, while the role of the thoracoscopic approach has yet to be clearly defined.

AIM

To preoperatively detect patients with a giant hiatal hernia in whom it would not be safe to perform laparoscopic surgery and who, therefore, would be candidates for a thoracoscopic approach.

METHODS

In the present study, using imaging test we preoperatively simulate the field of vision of the camera and the working area (instrumental access) that can be obtained in each patient when the laparoscopic approach is used.

RESULTS

From data obtained, we can calculate the access angles that will be obtained in a preoperative computerised axial tomography coronal section, according to the location of the trocar. We also provide the formula for performing the angle calculations If the trocars are placed in loss common situations, thus enabling us to determine the visibility and manoeuvrability for any position of the trocars.

CONCLUSION

The working area determines the cases in which we can operate safely and those in which certain areas of the hernia cannot be accessed, which is when the thoracoscopic approach would be safer.

The relationship of tear osmolarity with tear meniscus curvature and contact angles in healthy subjects: anterior segment optical coherence tomography study

PURPOSE

To evaluate the relationship of tear osmolarity (TO) with tear meniscus curvature and contact angles by anterior segment optical coherence tomography (AS-OCT) in healthy subjects.

METHODS

The right eyes of 64 consecutive healthy subjects were included in the study. The eyes were scanned by AS-OCT for the measurements of upper and lower tear menisci. The geometrical components of the upper and lower menisci, including height, depth, area, and radius of the menisci, cornea-meniscus angle (α-angle), meniscus-eyelid angle (β-angle), and curvature angle (θ-angle) were measured. TO was obtained by TearLab. All participants were administered Ocular Surface Disease Index questionnaires (OSDI), and tear film break-up time (TBUT), Schirmer I and II test measurements were also performed.

RESULTS

There was no association of TO with height, depth, and area of both menisci while TO was negatively correlated to θ-angle and radius of the lower eyelid meniscus (r = - 0.41, P < 0.001 and r = - 0.40, P < 0.01, respectively). The θ-angle and the radius of the lower meniscus were also significantly associated with OSDI score, TBUT, Schirmer I and II (P < 0.01 for all). There was a statistically strong correlation between the θ-angle and the radius of the lower meniscus (r = 0.91, P < 0.001).

CONCLUSION

The curvature angle and radius of the lower meniscus are significantly associated with TO. The curvature angle of the lower meniscus is a useful non-contact measure that may provide information indirectly about the osmolarity and the quality of the tear.

Segmented lordotic angles to assess lumbosacral transitional vertebra on EOS

PURPOSE

To test the vertical posterior vertebral angles (VPVA) of the most caudal lumbar segments measured on EOS to identify and classify the lumbosacral transitional vertebra (LSTV).

METHODS

We reviewed the EOS examinations of 906 patients to measure the VPVA at the most caudal lumbar segment (cVPVA) and at the immediately proximal segment (pVPVA), with dVPVA being the result of their difference. Mann-Whitney, Chi-square, and ROC curve statistics were used.

RESULTS

172/906 patients (19%) had LSTV (112 females, mean age: 43 ± 21 years), and 89/172 had type I LSTV (52%), 42/172 type II (24%), 33/172 type III (19%), and 8/172 type IV (5%). The cVPVA and dVPVA in non-articulated patients were significantly higher than those of patients with LSTV, patients with only accessory articulations, and patients with only bony fusion (all p < .001). The cVPVA and dVPVA in L5 sacralization were significantly higher than in S1 lumbarization (p < .001). The following optimal cutoff was found: cVPVA of 28.2° (AUC = 0.797) and dVPVA of 11.1° (AUC = 0.782) to identify LSTV; cVPVA of 28.2° (AUC = 0.665) and dVPVA of 8° (AUC = 0.718) to identify type II LSTV; cVPVA of 25.5° (AUC = 0.797) and dVPVA of - 7.5° (AUC = 0.831) to identify type III-IV LSTV; cVPVA of 20.4° (AUC = 0.693) and dVPVA of - 1.8° (AUC = 0.665) to differentiate type II from III-IV LSTV; cVPVA of 17.9° (AUC = 0.741) and dVPVA of - 4.5° (AUC = 0.774) to differentiate L5 sacralization from S1 lumbarization.

CONCLUSION

The cVPVA and dVPVA measured on EOS showed good diagnostic performance to identify LSTV, to correctly classify it, and to differentiate L5 sacralization from S1 lumbarization.

Effect of cylinder-liner rotation on wear rate: An experimental study

In rotating cylinder-piston system, the largest losses source is frictional losses, accounting for 50% of the total frictional losses, thus it is important to optimize. Effect of incremental rotation of a cylinder liner on its wear rate was investigated. The engine speed, load and the cylinder rotating angle were the main parameter. The results showed that the wear rate may be reduced to the half simply by rotating cylinder liner every six hours’ time interval of working. The test was carried out in pairs using a piston cylinder with movable liner and compared to a standard cylinder liner (fixed liner). Angles of 60^o, 120^o, 180^o, 240^o, and 300^o were used for incremental movement. The same operating conditions for two cylinders were maintained for the purpose of comparison. Beneficial effects of reducing the wear rate for all components of the piston-cylinder arrangement associated with incremental rotational movement of a cylinder linear were noticed. A decrease in wear rate was obvious in the cylinder liner in rotation angles of 120^o and 240^o and it is almost one-fourth of the wear that occurs in the stationary cylinder liner.

Effect of PLIF and TLIF on sagittal spinopelvic balance of patients with degenerative spondylolisthesis

OBJECTIVE

The aim of this study was to evaluate the effects of PLIF and TLIF on sagittal spinopelvic balance and to compare radiological results of two surgical procedures with regard to spinopelvic parameters.

METHODS

Thirty-five patients (34 female and 1 male; mean age: 52.29 ± 13.08 (range: 35-75)) with degenerative spondylolisthesis cases were included in the study. Patients were divided into two groups according to surgical technique: PLIF and TLIF. The level and the severity of listhesis according to Meyerding classification were assessed and spinopelvic parameters including sacral slope, pelvic tilt, pelvic incidence (PI), lumbar lordosis, and segmental lumbar lordosis were measured on digital X-rays. All preoperative and postoperative parameters and the results were compared between two groups.

RESULTS

The age distribution was similar in both groups (p = 0.825) and there was no difference between the mean PI of the groups (p = 0.616). In 15 patients, spondylolisthesis level were at the L5-S1 level (PLIF: 8, TLIF: 7), in 16 patients at the L4-L5 level (PLIF: 6, TLIF: 10) and in 4 patients at the L3-L4 level (PLIF: 2, TLIF: 2). According to Meyerding classification, before the operation, the sliding grades were 0 in 4 patients, 1 in 21 patients, 2 in 7 patients, and 3 in 3 patients. The grades changed into 0 in 28 patients, 1 in 5 patients, and 2 in 2 patients after surgery. There were no differences in the grade of listhesis between PLIF and TLIF groups preoperatively (p = 0.190) and postoperatively (p = 0.208). In both groups, the spondylolisthesis-related deformities of patients were significantly corrected after surgery (p < 0.001).

CONCLUSION

PLIF and TLIF techniques have similar radiological results in restoring the sagittal spinopelvic balance in patients with degenerative spondylolisthesis. Both techniques are good options to achieve reduction and fusion in patients with degenerative spondylolisthesis, but have no advantage over each other for restoring spinopelvic balance.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

Anatomical study of petrous and cavernous parts of internal carotid artery

The petrous and cavernous parts of internal carotid artery (ICA) are obscure and are not readily accessible to observation/imaging. These parts have broad biological and medical interest because of their peculiar shape. Given the their clinical importance and the scarce data available based mostly on imaging, the present study was aimed at studying these parts of ICA by dissection. The study was carried out on 56 ICAs obtained from embalmed adult cadavers and 10 ICAs from five fetuses. The foetal ICAs were studied in situ. The morphometric analysis of the adult ICA was done after its removal from cranial cavity to gain an insight into the geometry of the vessel, i.e., length, various bends, and diameters at various locations. ICAs in fetuses ran a relatively straighter course taking gentle curves at three positions (two intrapetrous, one cavernous). Adult ICAs were more tortuous and exhibited greater variability in length and angulations. The length of respective portions of the ICA correlate negatively with the measure of angles. The angles in the petrous and cavernous parts were positively correlated to each other. The carotid siphon was positively, highly significantly correlated to other angles. Longer vessels are more tortuous with acute bends. An acute carotid siphon is an indication of more tortuous ICA. The findings of the present study have created a reference data of unsuspected adult population and has potential implications for studying cause/effect relationship of vessel geometry and hemodynamic factors.

Morphometric analysis of posterior fossa in Indian CP angle acoustic schwannoma patients

AIM

To study the morphometry of posterior fossa in Indian CP angle schwannoma patients in order to know its influence on the extent of excision of the CP angle acoustic schwannomas.

MATERIALS AND METHODS

One hundred cases of cerebellopontine angle schwannomas treated surgically by the senior author and 20 controls between January 2006 and June 2011 were consecutively investigated with computed tomography (CT) using the high-resolution CT bone windows before surgery. Evaluation of anatomic parameters of the petrous bone and posterior fossa cavity were done in all patients and controls. Data were entered in Excel software and were analyzed using NCSS software. All possible regression analysis was done to select the important variables to be included in the model to predict the excision of tumor with these variables. A prediction model was developed defining the binary outcome as total excision or subtotal excision as dependent variable and the morphometric data and grading of tumor as independent variables.

RESULTS

Interpetrous distance (IP) is the distance between the two petrous apices. Sigmoid distance (IS) distance is the distance between the two sigmoid points. Sigmoid point is the point at which the scalloped impression of the sigmoid sinus straightens to join the occipital bone posteriorly. SAG is the distance between the mid IP point and the mid-point on the inner wall of the occipital bone. The PM angle was 47.8±4.14 degrees (38-58), the PA angle was 42.68±4.47 degrees (34-53), the IP distance was 2.07±0.13 cm (1.5-2.8), the sagittal diameter of posterior fossa was 6.22±0.73 cm (5.1-9.8) and the intersigmoid distance was 9.45±0.73 cm (7.4-11). There was no significant gender difference in the posterior fossa morphometry between patients and controls. Inter-sigmoid distance and the petrous-apex angle were more in the Indians when compared to the European population mentioned in the Mathies and Samii study.

CONCLUSIONS

The posterior fossa morphological parameters of the Indian and European population differ significantly. Inter-sigmoid distance and the petrous-apex angle were more in the Indians when compared to the Europeans. There is no significant gender difference in the morphometry of the Indians. There is no significant difference between the patients and the control groups. In our study the adhesions with surrounding structures along with the posterior fossa morphometry significantly affect the extent of excision.

Estimation of radiographic angles and distances in coronal part of mandibular molars: A study of panoramic radiographs using EMAGO software

Objective:

This study was designed to investigate radiographically the effects of age and external irritating stimuli on the morphology and thickness of the pulp chamber ceiling and floor in mandibular molars.

Materials and Methods:

A total of 234 panoramic radiographs were recruited and 494 mandibular molars were examined in this study. The sample was divided into six age groups: Group 1, <20 years; Group 2, 20-29 years; Group 3, 30-39 years; Group 4, 40-49 years; Group 5, 50-59 years and Group 6, >60 years. Each group was subdivided into two subgroups with regard to the tooth condition (intact or non-intact teeth). Four distances, two angles and two ratios were measured, in order to estimate the dimensions of the pulp chamber and the thickness of the pulp chamber ceiling and floor.

Results:

The thickness of the pulp chamber ceiling and floor increased significantly from Group 1 to 6. The pulp chamber floor angle presented progressive sharpness from Group 1 to 6 whereas the pulp chamber ceiling angle presented progressive bluntness from Group 1 to 5 and sharpness from Group 5 to 6. Significant differences were identified in the thickness of the pulp chamber ceiling, the thickness of the pulp chamber floor and the ceiling-floor distance between intact and non-intact teeth.

Conclusion:

Based on those results, there are differences in the location of secondary dentin formation between the two pulp chamber walls. Age is related to diminished pulp chamber size. The increase rate of the pulp chamber ceiling thickness is similar to that of the pulp chamber floor thickness. Furthermore, external irritating stimuli have an effect on the pulp chamber dimensional changes.