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BACKGROUND The reliability of methods for identifying the circumferential position of small lower esophageal lesions is unknown. We prospectively investigated a new method that presents lesion positions as times on a clock face. METHODS Eighty-seven patients were consecutively examined by endoscopy. After observing the esophagus, an endoscope was inserted into the stomach and fixed, and the greater curvature folds at the upper gastric corpus were set as horizontal on the endoscope monitor display. The scope was retrogressed into the lower esophagus. At this point, the right wall at the hiatus is at the 3 o'clock position (R-line). The scope was then retrogressed from the gastric angle to the cardia along the center of the lesser curvature in the retroflexed view to obtain the LC-line (the center of the lesser curvature at the cardia). The LC-line in the esophageal hiatus in the frontal view was then identified, and the angle between the R- and LC-lines (R-LC) was measured. RESULTS After excluding 7 patients with hernias >2 cm and 3 with esophageal stenosis, data from 77 patients were analyzed. The R-LC angle ranged from -38° to +35°. The mean R-LC angle was -0.3°± 15.9°, and its 95% confidence interval was [-4.0°, 3.3°] within [-15°, + 15°]. When indicating lesion locations as times on a clock face, there was an error of ±30 min (±15°); therefore, R- and LC-lines were shown to be identical on an equivalence test. CONCLUSIONS This new method allows the circumferential position of small lower esophageal lesions to be reliably represented as a clock face.

Purpose To explore whether patient position influences a surgeon’s ability to accurately judge anchor position on the glenoid. Materials and Methods Two anchors were inserted into the glenoid of 8 shoulders. Arthroscopic videos were taken from 3 views (posterior beach chair [pBC], posterior lateral decubitus [pLD], and anterosuperolateral decubitus [asLD]). The shoulders were disarticulated to identify “true” anchor position. Seventeen shoulder surgeons reviewed the videos and indicated anchor positions using the “clock face” method. Accuracy was measured within tolerances, ranging from zero (exact), 0.5 (half-hour), 1.0, and 1.5 hours of “true” position. Intra- and inter-rater agreement was calculated. Post hoc analyses explored for bias dependent on surgical side. Results The overall accuracy was 34.0%. At tolerances of 0.5, 1.0, and 1.5 hours, accuracy increased to 82.4%, 95.4%, and 98.0%. With a 30° scope, identification of exact position was more accurate in pBC than pLD (odds ratio [OR] = 1.397; P = .029) but not asLD (OR =1.341; P = .197). At a tolerance of 0.5 hour, the 30° scope was more accurate in pBC than both pLD (OR = 1.444; P = .011) and asLD (OR = 1.728; P = .009). In left shoulders, anchors were perceived as more inferior than true position in asLD and pLD. In right shoulders, anchors were perceived as more superior than true position from pBC and pLD. Inter- and intrarater agreement were highest in pBC with a 30° scope (30° scope weighted kappa = 0.783 and 70° scope weighted kappa = 0.853, respectively). Conclusion Judgment of anchor position on video is most accurate in a pBC view. Inter- and intrarater reliability were also highest from a pBC view.

Background: Over the past 30 years, the clock drawing test (CDT) has generated considerable interest due to its usefulness in the early detection of cognitive impairments, particularly those seen in neurodegenerative dementias (including Alzheimer’s disease), vascular dementia, and mixed dementia. The present study aimed to determine whether the results of the “30-Point Clock Face Test” (CFT-30), a standardized version of the CDT that uses a 30-point scale, correlate with those of the Mini-Mental State Examination (MMSE). Methods: This is a retrospective, observational study. All patients hospitalized in a Hospital-University Clinic Geriatrics Unit (Grenoble Alpes University Hospital, Grenoble, France), from January 1, 2017, to December 31, 2018, were included. Patient data and scores were retrieved from hospital archives, and the results of the two tests of interest, MMSE and the CFT-30, were analyzed. Results: We included 214 patients aged ≥75 years. The mean ± SD age was 86.4 ± 5.6 years, and 68.7% were female. A strongly positive, significant correlation was seen between the CFT-30 and MMSE ( r = 0.73, P < 0.001) scores. The total scores obtained by these two tests were identical ( t = 1.22, P = 0.22). Conclusion: CFT-30 is a good complement to the tools usually used in the investigation of cognitive impairments in older people. In addition to its metrological qualities, the standardized and normalized CFT-30 is extremely simple and very fast to use.

The article clarifies the possible sources of Osip Mandelstam’s poem “No, not the moon, but a bright clock-face...” (1912, first published 1913). A new interpretation of references to K. Batyushkov, which more than once attracted the attention of poet’s contemporaries and modern researchers, is proposed. According to the author of the article, Mandelstam, theoretically asserting the “thingness” (even super-lightness, quintessence of thingness) of surrounding world as the very essence of poetry, enters into a consistent debate with the mad poet, and through Batyushkov — with Symbolism as a certain world outlook and the artistic system reflecting it. The poem sets a contrast between the phenomena of life that live in real time of the shaky eternity of Symbolism, which fits into the general context of the book “Stone”. As a result of a detailed analysis, it is concluded that Mandelstam’s little poem “No, not the moon...” played a significant role in the history of Russian poetry. At the very initial stage, it reflected the opposition (struggle) of two most important poetic systems of the Silver Age — Symbolism and Acmeism.

“Peak Shift” usually occurs following intradimensional-discrimination training and involves a shift of the peak of the generalization gradient away from the original discriminative stimulus (S+) in a direction away from an S-. Two theoretical accounts of peak shift, the gradient interaction theory (GIT) and adaptation level theory (ALT), were compared. The effects of asymmetric test stimuli and the impact of instructions to participants for them to treat stimuli as members of categories on generalization gradients were investigated. In Experiment 1, the relation between peak shifts obtained when an extended asymmetric set of test stimuli was employed and the occurrence of categorization of the stimuli involved was investigated in four separate conditions. Two involved temporal discrimination, one involved line-angle discrimination, and one involved a compound line-angle and temporal cue discrimination. If participants treated the stimuli as belonging to discrete categories, such as hands-on a clock, rather than as being on continuous dimensions then responding to the compound cue was expected to result in attenuation of blocking of a peak shift. However, the peak shift obtained to the three cue types were the same. In Experiment 2, an independent group of participants was given explicit instructions to treat the line angles as if they were the hands of a clock face and this eliminated peak shift. The results from the present experiments support an ALT interpretation, although the peak shifts were significantly smaller in magnitude than predicted by this account.

Acetabular labral tear is a common pathology. In some clinical situations, primary labral repair may not be possible and labral reconstruction is indicated. Describe the anatomy of the indirect head of the rectus femoris (IHRF) tendon with clinical application in arthroscopic labral reconstruction surgery. Twenty-six cadaver hips were dissected. Thirteen measurements, each with clinical relevance to arthroscopic labral reconstruction using an IHRF tendon graft were taken on each hip. All measurements were taken in triplicate. Mean values, standard deviations and intra-observer reliability were calculated. The mean footprint of the direct head of the rectus femoris tendon was 10.6 mm × 19.6 mm. The width and thickness at the confluence of both heads were 10.9 mm and 6.9 mm, respectively. The mean total length of the footprint and “free portion” of the IHRF was 55.3 mm, the mean cranial to caudal footprint measured at the 12 o’clock, 1 o’clock, and 2 o’clock positions were 22.3 mm. The mean length of the Indirect Head footprint alone was 38.1 mm. The mean length of IHRF tendon suitable for grafting was 46.1 mm and the mean number of clock face sectors covered by this graft was 3.3 clock face sectors. Intra-observer reliability was ≥ 0.90 for all recorded measurements. The origin of the IHRF on the acetabulum fans out posteriorly, becoming thinner and wider as the origin travels posteriorly. The tendon footprint is firmly attached on the lateral wall of the ilium and becomes a free tendon overlying the acetabular bone as it travels anteriorly and distally towards its muscular attachment. The IHRF tendon is in an ideal location for harvesting and contains the appropriate thickness, length and triangular architecture to serve as a safe and local graft source for acetabular labral reconstruction surgery.

In this study, we contrasted two hypotheses theorizing the role of the global shape of a boundary in object location memory: People might differentiate reference points based on the global shape extracted from the environment configuration and choose appropriate parts for encoding a specific location, or, alternatively, only the number of reference points provided by a shape might be important for accurate encoding. We designed a location memory task in an immersive virtual environment in order to examine these two hypotheses. Participants first learned four target locations with a circular wall and a landmark array. During testing, participants recalled the locations with either one entire cue or part of one cue removed. Location memory was impaired when the testing cues did not form a circle, but it was not impaired when the testing configuration retained the circular shape. In Experiment 2, the circle formed by a landmark array and the circular wall did not share the same center during learning. Memory performance decreased when either the wall or the landmark array was removed during testing. These results indicated that participants might segment the shape of the circular wall into parts (similar to segmenting a clock face into 12 hours) and encode target locations relative to the differentiated parts. When such segmentation could be recovered from the testing configuration, object location memory was retained. Otherwise, impairment occurred during testing. These findings suggest that although the individual reference points on a boundary are important for encoding specific target locations, the global shape of the boundary nonetheless affects segmentation and the selection of individual reference points.

PURPOSE To use computer models and image analysis to identify the position on the head-neck junction visualized in 10 radiographic views used to quantify cam morphology. METHODS We generated 97 surface models of the proximal femur from computed tomography scans of 59 control femurs and 38 femurs with cam morphology-a flattening or convexity at the femoral head-neck junction. Each model was transformed to a position that represents the anteroposterior, Meyer lateral, 45° Dunn, modified false-profile, Espie frog-leg, modified 45° Dunn, frog-leg lateral, cross-table, 90° Dunn, and false-profile views. The position on the head-neck junction visualized from each view was identified on the surfaces. This position was then quantified by a clock face generated on the plane of the head-neck junction, in which the 12-o'clock position indicated the superior head-neck junction and the 3-o'clock position indicated the anterior head-neck junction. The mean visualized clock-face position was calculated for all subjects. Analysis was repeated to account for variability in femoral version. A general linear model with repeated measures was used to compare each radiographic view and anteversion angle. RESULTS Each radiographic view provided visualization of the mean clock-face position as follows: anteroposterior view, 12:01; Meyer lateral view, 1:08; 45° Dunn view, 1:40; modified false-profile view, 2:01; Espie frog-leg view, 2:14; modified 45° Dunn view, 2:35; frog-leg lateral view, 2:45; cross-table view, 3:00; 90° Dunn view, 3:13; and false-profile view, 3:44. Each view visualized a different position on the clock face (all P < .001). Increasing simulated femoral anteversion by 10° changed the visualized position of the head-neck junction to a more clockwise position (range, 0:07 to 0:29; all P < .001), whereas decreasing anteversion by 10° visualized a more counterclockwise position (range, -0:23 to -0:08; all P < .001). CONCLUSIONS Ten common radiographic views used to identify cam morphology visualized different clock-face positions of the head-neck junction. Our data will help clinicians to understand the position of the head-neck junction visualized for each radiographic view and make educated decisions in the selection of radiographs acquired in the clinic. CLINICAL RELEVANCE Our findings will aid clinicians in choosing a set of radiographs to capture cam morphology in the assessment of patients with hip pain.

Background: A companion paper (Crowley et al., 2020) reports on the neuroimaging and neuropsychological profiles of statistically determined idiopathic non-dementia Parkinson’s disease (PD). Objective: The current investigation sought to further examine subtle behavioral clock drawing differences within the same PD cohort by comparing 1) PD to non-PD peers on digitally acquired clock drawing latency and graphomotor metrics, and 2) PD memory, executive, and cognitively well phenotypes on the same variables. Methods: 230 matched participants (115 PD, 115 non-PD) completed neuropsychological tests and dCDT. Statistically-derived PD cognitive phenotypes characterized PD participants as PD low executive (PDExe; n = 25), PD low memory (PDMem; n = 34), PD cognitively well (PDWell; n = 56). Using a Bayesian framework and based on apriori hypotheses, we compared groups on: total completion time (TCT), pre-first hand latency (PFHL), post-clock face latency (PCFL), total clock face area (TCFA), and total number of pen strokes. Results: Fewer strokes and slower performance to command were associated with higher odds of PD diagnosis, while a larger clock face in the copy condition was associated with lower odds of PD diagnosis. Within PD cognitive phenotypes, slower performance (TCT, PCFL) and smaller clock face to command were associated with higher odds of being PDExe than PDWell, whereas larger clock faces associated with higher odds of being PDMem than PDWell. Longer disease duration, more pen strokes (command) and smaller clocks (command) associated with higher odds of being PDExe than PDWell. Conclusion: Digitally-acquired clock drawing profiles differ between PD and non-PD peers, and distinguish PD cognitive phenotypes.

Background: A digital version of the clock drawing test (dCDT) provides new latency and graphomotor behavioral measurements. These variables have yet to be validated with external neuropsychological domains in non-demented adults. Objective: The current investigation reports on cognitive constructs associated with selected dCDT latency and graphomotor variables and compares performances between individuals with mild cognitive impairment (MCI) and non-MCI peers. Methods: 202 non-demented older adults (age 68.79 ± 6.18, 46% female, education years 16.02 ± 2.70) completed the dCDT and a comprehensive neuropsychological protocol. dCDT variables of interest included: total completion time (TCT), pre-first hand latency (PFHL), post-clock face latency (PCFL), and clock face area (CFA). We also explored variables of percent time drawing (i.e., 'ink time') versus percent time not drawing (i.e., 'think time'). Neuropsychological domains of interest included processing speed, working memory, language, and declarative memory. Results: Adjusting for age and premorbid cognitive reserve metrics, command TCT positively correlated with multiple cognitive domains; PFHL and PCFL negatively associated with worse performance on working memory and processing speed tests. For Copy, TCT, PCFL, and PFHL negatively correlated with processing speed, and CFA negatively correlated with language. Between-group analyses show MCI participants generated slower command TCT, produced smaller CFA, and required more command 'think' (% Think) than 'ink' (% Ink) time. Conclusion: Command dCDT variables of interest were primarily processing speed and working memory dependent. MCI participants showed dCDT differences relative to non-MCI peers, suggesting the dCDT may assist with classification. Results document cognitive construct validation to digital metrics of clock drawing., National Science Foundation (Grant 1404333)

Background: The clock-drawing test (CDT) is a neuropsychological screening tool largely used to explore cognitive functioning. It requires participants to draw an analog clock face. Many studies have reported a good correlation between the CDT and the Mini-Mental State Examination (MMSE). The CDT has also showed a variable specificity. There are, however, some inconsistencies concerning the effect of sociodemographic variables (sex, age, education) on clock-drawing abilities. The present study aimed at examining these issues in a sample of middle-aged/young-old healthy adults. Method: Participants (n = 97) performed the MMSE and CDT. Clock drawings were assessed by five formal scoring systems (Wolf-Klein, Watson, Freedman, Manos, Shulman). In addition, three naïve raters provided a dichotomous judgment (normal vs. abnormal) for each clock. Results: Sociodemographic variables did not affect CDT performance. Unlike earlier studies, CDT scores did not correlate with MMSE. Moreover, test specificity was appropriate only for Freedman’s, Shulman’s, and Wolf-Klein’s methods. Interestingly, some participants drew clocks with numbers as they appear in digital clocks. By re-running the statistical analyses after removing these atypical clocks, four out of the five formal scores showed a significant correlation with MMSE; furthermore, CDT specificity slightly increased for all scoring systems including naïve ratings. Conclusions: CDT is not affected by sociodemographic variables. The finding of some clocks with digitally represented numbers suggests the need to align neuropsychological assessments with demands from an increasing digitalized environment. Moreover, the occurrence of high false-positives and possible digital contaminations suggest great caution in interpreting the clinical significance of CDT.

Purpose. To present an advanced ultrasound (US) technique and propose its use as a screening diagnostic tool for temporomandibular joint (TMJ) internal derangement. Materials and Methods. The technique is based on maintaining the US probe parallel to the articular disc, rather than traditional axial and coronal views, with the position described relative to a clock face. Validation was achieved by direct comparison with magnetic resonance imaging (MRI). A total of 61 patients, with age ranging from 13 to 67 years, were prescreened for TMJ pain and internal derangement, underwent US imaging for screening, and MRI evaluation for final diagnosis. Results. 29 of the 61 patients had disc pathology on MRI. US screening produced no false positive results and only 6 false negative results, corresponding to a sensitivity of 79% and specificity of 100%. Half of the false negative cases involved disc pathology with a medial component to the disc displacement. Conclusion. US is both a sensitive and a specific screening tool for TMJ dysfunction when used by an appropriately trained operator, with the exception of medially displaced discs. If TMJ assessment is found to be abnormal, the patient should be referred for MRI, and any patient scheduled for surgery must have the diagnosis confirmed by MRI. If a component of medial disc displacement is suspected, MRI should be performed despite a normal screening US.

Though controversial, the “clock face view” of the intercondylar notch remains a way some surgeons communicate regarding placement of the femoral tunnel in anterior cruciate ligament reconstruction. The purpose of this study was to quantify the differences in angle measurement between several previous descriptions of the clock face view by using a new reference standard. Three-Tesla magnetic resonance imaging (MRI) was used to scan 10 human knees to create three-dimensional MRI-based bony models which were used for measurements. A standardized clock face view was developed with the knee flexed to 90° using the junction of the cartilage and cortex of the medial and lateral surfaces of medial and lateral femoral condyles as the 3 o'clock and 9 o'clock, respectively, with the 12 o'clock established as the midpoint of the roof of the intercondylar notch. With the knee viewed at 90° of flexion, an “idealized” femoral tunnel position was plotted on the medial wall of the lateral femoral condyle at 30° (corresponding to the 10 o'clock or 2 o'clock position). The clock faces as described by Edwards et al, Heming et al, and Mochizuki et al were each then overlaid on this same model and the difference in measurement calculated. The average angles measured when the previously described clock faces were projected onto the idealized clock face view comparing a mark made at 30° were 47.7°, 7.2°, and 49.8° for the methods described by Edwards et al, Heming et al, and Mochizuki et al, respectively (all p

Background: Relative to the abundance of publications on dementia and clock drawing, there is limited literature operationalizing ‘normal’ clock production. Objective: To operationalize subtle behavioral patterns seen in normal digital clock drawing to command and copy conditions. Methods: From two research cohorts of cognitively-well participants age 55 plus who completed digital clock drawing to command and copy conditions (n = 430), we examined variables operationalizing clock face construction, digit placement, clock hand construction, and a variety of time-based, latency measures. Data are stratified by age, education, handedness, and number anchoring. Results: Normative data are provided in supplementary tables. Typical errors reported in clock research with dementia were largely absent. Adults age 55 plus produce symmetric clock faces with one stroke, with minimal overshoot and digit misplacement, and hands with expected hour hand to minute hand ratio. Data suggest digitally acquired graphomotor and latency differences based on handedness, age, education, and anchoring. Conclusion: Data provide useful benchmarks from which to assess digital clock drawing performance in Alzheimer’s disease and related dementias.

Background When performing the clock-drawing test healthy participants often draw the clock face using a counter clockwise movement. The reason for this circular directional bias is not known. These actions may be related to the development of motor or attentional programs that associate leftward with downward movements, and rightward with upward movements. Methods To further examine this down-left, up-right programming hypothesis, we examined the direction of circular movements made during cursive writing by dividing the first curved movements into the following pairs, up versus down, and leftward versus rightward. Results and conclusions With almost all the letters analyzed, when initially moving upward there was a simultaneous rightward movement and when initially moving downward a leftward movement. The results suggest that there appears to be a relationship between downward and leftward movements as well as between upward and right rightward movements. In addition, there is some evidence to suggest that the right-upward movements may be mediated by the left hemisphere and left-downward movements by the right hemisphere. Although our results suggest motor or spatial attentional programs may account for counter clockwise face drawing, activities such as learned writing direction may influence this spatial bias. Therefore, additional research is needed to better understand if these spatial biases are learned or intrinsic and the neuropsychological mechanisms that might account for these asymmetries.

Femoroacetabular impingement syndrome is a common hip pathology significantly affecting not only the intra- and extra-articular structures but also the biomechanical function of the joint. Cam and pincer bony lesions have been extensively studied. However, during recent years, other types of extra-articular impingement between the pelvic and femoral bone have been investigated. When a prominent or morphologically abnormal anterior-inferior iliac spine (AIIS) impinges repetitively on the femoral side during motion, the subspinal acetabular region becomes prominent and extends toward the intra-articular part of the joint. This results in restriction of the range of motion of the hip and pain, especially with flexion. Therefore, during hip arthroscopy, it is necessary to evaluate the subspinal region (triangular area located at 1:30 to 2:30 o'clock using the acetabular clock face system). For the correction of the acetabular bone pathology to be complete, the surgeon should focus both on the pincer and subspinal impingement lesions. This article describes our preferred technique to successfully address subspinal and pincer acetabular impingement during hip arthroscopy. The pearls and pitfalls of this technique are discussed.

Objectives The aim was to validate a computational patient specific model of Zenith® fenestrated device deployment in abdominal aortic aneurysms to predict fenestration positions. Methods This was a retrospective analysis of the accuracy of numerical simulation for fenestrated stent graft sizing. Finite element computational simulation was performed in 51 consecutive patients that underwent successful endovascular repair with Zenith® fenestrated stent grafts in two vascular surgery units with a high volume of aortic procedures. Longitudinal and rotational clock positions of fenestrations were measured on the simulated models. These measurements were compared with those obtained by (i) an independent observer on the post-operative computed tomography (CT) scan and (ii) by the stent graft manufacturer planning team on the pre-operative CT scan. (iii) Pre- and post-operative positions were also compared. Longitudinal distance and clock face discrepancies >3 mm and 15°, respectively, were considered significant. Reproducibility was assessed using Bland–Altman and linear regression analysis. Results A total of 195 target arteries were analysed. Both Bland–Altman and linear regression showed good reproducibility between the three measurement techniques performed. The median absolute difference between the simulation and post-operative CT scan was 1.0 ± 1.1 mm for longitudinal distance measurements and 6.9 ± 6.1° for clock positions. The median absolute difference between the planning centre and post-operative CT scan was 0.8 ± 0.8 mm for longitudinal distance measurements and 5.1 ± 5.0° for clock positions. Finally, the median absolute difference between the simulation and the planning centre was 0.96 ± 0.97 mm for longitudinal distance measurements and 4.8 ± 3.6° for clock positions. Conclusions The numerical model of deployed fenestrated stent grafts is accurate for planning position of fenestrations. It has been validated in 51 patients, for whom fenestration locations were similar to the sizing performed by physicians and the planning centre.

Labelled human comfort data can be a valuable resource in optimising the built environment, and improving the wellbeing of individual occupants. The acquisition of labelled data however remains a challenge. This paper presents a methodology for the collection of in-situ occupant feedback data using a Fitbit smartwatch. The clock-face application cozie can be downloaded free-of-charge on the Fitbit store and tailored to fit a range of occupant comfort related experiments. In the initial trial of the app, fifteen users were given a smartwatch for one month and were prompted to give feedback on their thermal preferences. In one month, with minimal administrative overhead, 1460 labelled responses were collected. This paper demonstrates how these large data sets of human feedback can be analysed to reveal a range of results from building anomalies, occupant behaviour, occupant personality clustering, and general feedback related to the building. The paper also discusses limitations in the approach and the next phase of design of the platform.

Background For shoulder arthroscopy, few anatomical landmarks are available and inexperienced surgeons tend to be adrift due to the limited visual field of the scope. The purpose of this study was to demonstrate the useful landmarks around the glenoid for accurate orientation, and also the safe distance to avoid suprascapular nerve injury during surgical procedures around the glenoid. Methods In 15 human solution-fixed cadavers, a cross-section of the shoulder joint on the labrum surface was created. The positions of the principal anatomical structures surrounding the glenoid were marked on the labrum and measured using our clock face indication system. In 9 shoulders the distances from the labral surface to the spinoglenoid notch were recorded. As an indicator of the scapula size, the distances between the superior and inferior angles of the scapula were also measured. Results The average landmark positions in the right shoulder were as follows: center of the attachment of the long tendon 11:59, anterior edge of the supraspinatus 11:59, posterior edge of the base of the coracoid process 12:13, superior edge of the subscapularis 1:03, anterior edge of the base of the coracoid process 1:25, inferior edge of the subscapularis 5:27, inferior edge of the teres minor 6:21, border of the infraspinatus and teres minor 7:43, center of the scapula spine 10:06, border of the supra and infraspinatus 10:27. The average distance from the labral surface to the spinoglenoid notch was 23.17 mm, and that from the superior to inferior angle was 144.93 mm. The Pearson correlation coefficient for these distances was 0.007. Conclusions The locations of anatomical landmarks surrounding the glenoid were reliably demonstrated using our clock face indication system. The expected distance from the labral surface to the suprascapular nerve was approximately 23 mm, irrespective of the size of the scapula.

STUDY DESIGN Retrospective Chart and CT Scan Review. OBJECTIVE To define the relationship of the pre-vertebral structures for each level to assist in easier intraoperative visualization. SUMMARY OF BACKGROUND DATA Vascular and visceral injuries from pedicle screws are well-known. This study will define the relationship of the pre-vertebral structures for each level to assist in avoiding potential complications. METHODS Pre- and post-operative CT scans were reviewed to define the pre-vertebral structures in relation to a clock-face. On reformatted axial slices, a clock-face was superimposed so that the left transverse process (TP) represented 8 o'clock and the right TP represented 4 o'clock. The positions of the TP on the clock-face did not change with rotation of the vertebra. RESULTS 108 patients had pre-operative CT scans. 78 had post-operative CT scans. Median age was 15 years, median Cobb angle was 50°, fused were 12, with 21 fixation points. 6324 axial CT slices were reformatted and analyzed. The trachea was located at 12 o'clock at T1, 1 o'clock at T2-T4, and between 12 and 1 o'clock at T5. The esophagus starts as a midline structure at 12 o'clock from T1-T2, moves to 11 o'clock from T3-T6, and further to 10 o'clock from T7-T9. The aorta starts at 10 o'clock at T5-T6, moves left at T7-T8 to 9 o'clock, and returns to 10 o'clock from T9-T11. It appears at 11'clock at T12, and at 12 o'clock from L1-L4. In about a third of cases, it is at 1 o'clock from L1 to L4, where it bifurcates. CONCLUSIONS This CT-based anatomical study provides a simple reference frame to help surgeons visualize the vital structures at each level. This three-dimensional visualization is facilitated by fixing the position of TP on the clock-face. Knowledge of this anatomical relationship can help avoid direct injury, and is easier to recall intra-operatively. LEVEL OF EVIDENCE 3.

The aim of this study was to determine the most appropriate approaches for fixation of each type and fragment of posterior malleolar fractures.A retrospective analysis of a prospectively collected database was performed on 141 posterior malleolar fractures. On the CT scan axial slice, a clock face was drawn using the posterolateral corner of the tibia as the centre and the Achilles tendon as the 6 o'clock axis. A box was then drawn from the fracture plane, with 90-degree lines corresponding to the medial perpendicular line (MPL) and lateral perpendicular line (LPL) extremity of the fracture and a central perpendicular line (CPL) (i.e. orthogonal central plane, for optimum screw placement). It was recorded where the MPL, LPL and CPL exited the clock face. All fracture patterns were further assessed by both senior authors regarding their choice of approach based on CPL and all variances resolved by discussion.The LPL was equivalent across the groups (except for the 2B medial fragments), indicating a consistent posterolateral corner fragment throughout the posterior malleolar sub types (p = 0.25). The medial aspect (MPL) of the type 1, type 2A and posterolateral fragments of type 2B were equivalent. The MPL of type 3 fractures was significantly more medial than type 1 and 2A fractures (p0.05), with the medial extremes of the type 2B posteromedial fragment being further medial. The majority of type 2B fractures (2/3rds) were determined to be best accessed through a combined posterolateral and medial posteromedial approach, with the other third via the posteromedial approach. Almost all type 3 fractures could be appropriately accessed through the PM approach.This study concludes that the extent of each subtype of posterior malleolar fractures are consistent. To fully expose each fracture differing incisions are necessary and should be in the skill mix for surgeons treating these fractures.4.

Alarm clocks are important aids that helps us keep a regular routine. This study explores two time-picking interfaces available on Android Smartphones, namely the digit-wheel and dial time-pickers. The digit-wheel time-picker exploits the traditional digit alarm clock metaphor where one cycles through a wheel of hours and a wheel of minutes using multiple small gestures. The dial time-picker is inspired by the analogue clock face and utilizes the real estate of the touch display though single gestures. A mixed experimental design was carried out to compare the efficiency of the two interfaces. The results show that on the first attempt, the digit-wheel time-picker is faster than the dial time-picker, but after a few attempts, the dial time-picker becomes significantly faster than the digit-wheel time-picker. Prior experience with the dial interface had only an interaction effect on the results.

Background The accuracy of surgeons in utilizing the clock face method for anchor placement has never been investigated. Our hypothesis was that shoulder arthroscopy surgeons would be able to place suture anchors at predetermined positions with accuracy and reliability. Methods Ten cadaveric shoulders were used. Five fellowship-trained shoulder arthroscopy surgeons were directed to place a suture anchor at 3:30, 4:30, and 5:30 clock in two shoulders each. The position of the anchors was determined with computed tomography. The accuracy of placement was calculated and data analyzed with one-way analysis of variance. The intraclass correlation coefficients were calculated. Results The overall accuracy was 57%. The accuracy of anchor placement at the 3:30 position was 40% (average position 2:24 o’clock), it was 50% at the 4:30 position (average position 3:42 o’clock) and 80% at the 5:30 position (average position 5:03 o’clock). No statistical difference in accuracy between the placement of the superior, middle, and inferior anchors (p = 0.145) was seen. The intraclass correlation coefficient for inter-surgeon reliability was 0.4 (fair) while the intraclass correlation coefficient for intra-surgeon reliability was 0.6 (moderate). Discussion The findings of this study suggest a moderate degree of accuracy and fair to moderate inter- and intra-surgeon reliability when using the clock face system to guide anchor placement.

Purpose The location of capitellar osteochondritis dissecans (OCD) lesions in the sagittal plane guides the surgical approach, and lesion location in the coronal plane influences surgical management. Although most lesions have been reported to occur between 4 o'clock and 4:30 (120° to 135° anterior to the humerus), some lesions are located elsewhere in the capitellum. The primary aim was to define the region of the capitellum affected by OCD lesions using a novel clock-face localization system. Methods We reviewed 104 magnetic resonance imaging examinations diagnosing a nontraumatic capitellar OCD lesion. In the sagittal plane, lesion margins were recorded as degrees on the capitellum and converted into a clock-face format in which 0° corresponds to 12:00 with the forearm facing to the right. The 0° axis (12-o'clock axis) was defined as a line parallel to the anterior humeral line that intersects the capitellum center. The following coronal measurements were recorded: lesion width, capitellar width, and distance between the lateral capitellum and lateral lesion. Two independent observers took measurements. Results In the sagittal plane, average lesion location was 92° to 150° (3:04–5:00, clock face) and ranged from 52.1° to 249.5° (1:44–8:19, clock face). Average lesion dimensions were 10.7 mm (mediolateral width) and 5.2 mm (anteroposterior depth). Interrater reliability was high (intraclass correlation coefficient = 0.98). Conclusions Using a magnetic resonance imaging–based clock-face localization system, we found that capitellar OCD lesions affect a broad region of the capitellum in the sagittal plane. Clinical relevance The clock-face localization system allows for precise description of capitellar OCD lesion location, which may facilitate intraoperative decision and longitudinal monitoring.

Liang et al. (2017) demonstrate how neuropeptides from two groups of clock cells appear to be responsible for the fly's circadian neurons becoming active at different times of day. By delaying the activity of their clock cell targets, they give rise to morning and evening behavior.

In 1900 signs, whether for giving information or as advertisements, had to be either paint on boards or print on paper—the traditional poster. Variable information presented even greater problems and here the choice was to use pointers over some form of fixed scale; the most obvious versions being the clock face and the electrical voltmeter and its variants. More random information needed manual intervention, such as the station master changing the painted wooden board to show the destination of the next train.

Winters, Kari-Lynn and Lori Sherritt-Fleming. Hungry For Math: Poems to Munch On, illustrated by Peggy Collins. Fitzhenry & Whiteside, 2015.Winters and Sherritt-Fleming seemingly intend this picture book to introduce those mathematical skills and concepts that children learn in their first years of schooling: shape recognition, counting, telling time, and using money. The authors append a glossary that defines such terms as “Base Ten,” “Ordinal numbers,” and “Rhombus.” Having raised our expectations that this will be a mathematically informative book, they get off to a bad start in a rhyme entitled “The Balanced Bee.” “Three circles, tall not wide,”Now, surely, if we are going to define a rhombus for the picture book crowd, we can also allow that a circle is a closed curve with all points on that curve equidistant from the centre. (In other words, it cannot be “tall not wide.”) Their presentation of the concept of time uses a variation on an old standby: “Hickory, Dickory Dock” in “Move Around the Clock.” At one time, the original rhyme was relevant to children because it referenced the nature of a clock. Sometimes, that clock had a pendulum or a sweep second hand to mark the passing seconds; always, it had hands that pointed to the minutes and the hours. Not all clocks chimed, but one could at least see the hands “strike” the hours. Most importantly, the numbers one to twelve circled the clock face and, thus, provided a visual clue to their sequence. Children learned of this sequence without being particularly aware of their learning.For today’s young child the typical “clock” is a digital strip on a microwave, or a smart phone, or an adult’s wrist strap. The numbers on it change either second by second or minute by minute. Staring at this strip which might, for example, read “1:30 p.m.”, how does a child know that “1:00 p.m.” arrived a half hour earlier, that “2:00 p.m.” will arrive a half hour hence, and that “12:30 a.m.” will arrive in a further eleven hours? The concept is no longer visually obvious. This book does not illuminate it. Despite a text which reads, “The mouse ran up the clock,” the mouse in Peggy Collins’ illustration does not run “up” anything: it hops along insouciantly through the gears and springs and winding key of a technology now unknown to children. Nor does the mouse progress systematically through the hours. The text accompanying its romp reads, “…three o’clock, four-thirty, seven o’clock…nine-thirty” …etc. Primary school teacherswould have to struggle to relate anything in this story sequence to the daily rotation of the earth, and humankind’s decision to mark its course in hours, minutes and seconds. Equally unhelpful is the rhymed story of the Spendosaur who wastes all his pennies at the candy store. The penny was discontinued in Canada two years before the publication of this book. The coin’s time honoured usefulness as a counting device or an introduction to base ten is kaput. Increasingly, we use credit cards at the shops. We buy online using computers and hand-held devices. We need not count change; we can simply enter a figure representing the cost of our purchase on a digital screen. In sum, Canadian children of primary school age scarcely remember that their parents once carried pennies in their pockets, let alone that they actually used the copper coins to make purchases. “One penny buys a chocolate-dipped pickle.” becomes merely a line of amusing nonsense.In part, uncertainty of intent may have led to this picture book’s various problems. It attempts to be both an entertaining fantasy and an engaging teaching tool. The blurring of purposes here has not quite succeeded. Reviewer: Leslie AitkenNot recommended: 1 star out of 4Leslie Aitken’s long career in librarianship included selection of books for school, public, special and academic libraries. She is a former Curriculum Librarian for the University of Alberta.

Purpose To assess interobserver and intraobserver agreement of estimating anterior cruciate ligament (ACL) femoral tunnel positioning arthroscopically using circular and linear (noncircular) estimation methods and to determine whether overlay template visual aids improve agreement. Methods Standardized intraoperative pictures of femoral tunnel pilot holes (taken with a 30° arthroscope through an anterolateral portal at 90° of knee flexion with horizontal being parallel to the tibial surface) in 27 patients undergoing single-bundle ACL reconstruction were presented to 3 fellowship-trained arthroscopists on 2 separate occasions. On both viewings, each surgeon estimated the femoral tunnel pilot hole location to the nearest half-hour mark using a whole clock face and half clock face, to the nearest 15° using a whole compass and half compass, in the top or bottom half of a linear quadrant, and in the top or bottom half of a linear trisector. Evaluations were performed first without and then with an overlay template of each estimation method. Results The average difference among reviewers was quite similar for all 4 circular methods with the use of visual aids. Without overlay template visual aids, pair-wise κ statistic values for interobserver agreement ranged from −0.14 to 0.56 for the whole clock face and from 0.16 to 0.42 for the half clock face. With overlay visual guides, interobserver agreement ranged from 0.29 to 0.63 for the whole clock face and from 0.17 to 0.66 for the half clock face. The quadrant method's interobserver agreement ranged from 0.22 to 0.60, and that of the trisection method ranged from 0.17 to 0.57. Neither linear estimation method's reliability uniformly improved with the use of overlay templates. Intraobserver agreement without overlay templates ranged from 0.17 to 0.49 for the whole clock face, 0.11 to 0.47 for the half clock face, 0.01 to 0.66 for the quadrant method, and 0.20 to 0.57 for the trisection method. Use of overlay templates did not uniformly improve intraobserver agreement for any estimation method. Conclusions There does not appear to be any advantage of using a half clock face or compass for estimating femoral tunnel position compared with a whole clock-face analogy. Visual reference aids appear to improve interobserver agreement (reliability) of circular analogies. The linear quadrant appears to be the most reliable method (fair to moderate agreement) for estimating femoral tunnel position without a visual aid for reference, but even better reliability, ranging from fair to good agreement, may be obtained by using the whole clock-face analogy with a visual aid. Clinical Relevance Increasing femoral tunnel position reliability may improve outcomes of ACL reconstruction surgery.

Video Objective The aim was to design a reproducible, easy to adopt method for teaching laparoscopic suturing and intracorporeal knot tying. The novel use of a clock face to guide the steps is proposed to simplify & accelerate skill acquisition. The technique appears far easier to conceptualize than many others and has been very positively received during laparoscopic masterclasses conducted at the Centre for Advanced Reproductive Endo-surgery in Sydney, Australia. Setting Laparoscopic suturing requires very different and more advanced skill sets compared to suturing at open procedures. Proficiency with these skills is essential for the completion of advanced minimally invasive gynecological procedures such as hysterectomy, myomectomy and sacrocolpopexy. Inadequate laparoscopic suturing skills have been identified as a key factor impeding the use and greater adoption of minimally invasive techniques for most gynecologists. Laparoscopic suturing is one of the most difficult skills in minimally invasive surgery due to multiple factors including a constrained working field, altered depth perception, the need for counterintuitive movements and also the lack of a standardized teaching technique. Interventions This video uses images and footage from a simulation laboratory to clearly illustrate the steps involved in mastering laparoscopic suturing and intracorporeal knot tying using novel clock face directions to guide the movements. Conclusion This technique has been successfully incorporated into masterclasses run at the Centre, where anecdotally participants have grasped the concepts involved in laparoscopic suturing more quickly than with previous techniques. A prospective study is planned to compare the use of the novel clock face instructional teaching to more conventional terminology.

Objective: The Clock Drawing Test (CDT) is widely used as a screening tool for discriminating cognitively normal individuals from patients with mild dementia. The aim of present study was to provide normative values for a 10-point quantitative scoring system proposed by Rouleau and colleagues (1992), including CDT total score and subscales score assessing representation of clock face (RC), layout of numbers (LN), and position of hands (PH), in a large sample of Italian healthy individuals. Method: Eight hundred and seventy-two Italian healthy participants (483 women; age range 20–94 years) with educational level from primary school to university underwent CDT and Mini Mental State Examination (MMSE). Results: Multiple linear regression analysis revealed that age and education significantly influenced CDT total score and its subscale scores. Moreover, a significant effect of gender was found only in RC subscale. From the derived linear equation, a correction grid for raw scores was built. Inferential cut-off values were estimated using a non-parametric technique and equivalent scores (ES) were computed. Correlation analysis showed a weakly significant correlation between adjusted CDT total score and adjusted MMSE scores. Conclusions: The present study provided normative data for the Rouleau and colleagues version of CDT in an Italian sample, useful for clinical and research purposes.

Purpose To investigate glenoid fixation for superior capsule reconstruction (SCR) and evaluate anchor positions, intraosseous trajectories, and proximity to the suprascapular nerve (SSN) and glenoid fossa. The secondary purpose was to provide technical pearls and pitfalls for anchor insertion on the superior glenoid during SCR. Methods Three beath pins were arthroscopically inserted into 12 (n = 12) nonpaired human cadaveric shoulders through Neviaser, anterior, and posterior portals to simulate anchor placement on the superior glenoid during SCR. Computed tomography scans were performed to evaluate anchor positioning and insertion trajectories. Specimens were then dissected to delineate the anatomic relations of the beath pins to the SSN and glenoid fossa. Results The superior glenoid anchor position was a mean 15.0 ± 4.0 mm to the SSN and 6.5 ± 1.7 mm to the glenoid fossa. The posterior glenoid anchor position was a mean 11.8 ± 2.1 mm to the SSN and 2.9 ± 2.9 mm to the glenoid fossa. On average, the superior pin was placed at 12:30 ± 0:30 (left-sided glenoid clock face) and inserted at 19° ± 9° with respect to the sagittal plane of the glenoid, the anterior pin was placed at 11:00 ± 0:30 and inserted 40° ± 17° off the glenoid, and the posterior pin was placed at 3:00 ± 1:00 and inserted at 52° ± 12° off the glenoid. Conclusions The results of the present cadaveric study showed that glenoid fixation was safe with respect to the SSN and delineated technical guidelines and trajectories for inserting 3 anchors into the glenoid. Clinical Relevance This study shows that 3 anchors can be inserted into the glenoid without a risk of SSN damage and delineates technical guidelines for anchor insertion.