Optimal mass of the arm segments in throwing: A two-dimensional computer simulation study

The purpose was to quantify the contributions of the thrower's linear translation and segmental rotations to the speed of the javelin. Eight male finalists at the 1995 USA Track and Field Championships were filmed at 100Hz. The two longest throws for each athlete were analyzed and the DLT method was used to obtain three-dimensional coordinates of thrower and javelin landmarks. Data were smoothed using quintic spline functions and the first derivatives of these functions provided instantaneous linear velocity values. Segment angular velocities and instantaneous contributions to javelin speed were computed using methods similar to those reported by Feltner et al. (J. Applied Biomech, 1996, 359-382). The general patterns of component contributions to javelin speed were similar for all analyzed throws. At left foot plant and the start of the double support period prior to release, over 75% of the speed of the javelin (X=7.4 m/s) was due to the linear velocity of the thrower's center of mass (c.m.). During the double support phase, the speed of the javelin rapidly increased and reached its release speed (X=28.1 m/s). During double support and until approximately 0.035 s before release, the horizontal adduction angular velocity of the upper arm was a major contributor to the speed of the javelin. However, the horizontal adduction angular velocity rapidly decreased immediately prior to release. At release, the largest contributors to the speed of the javelin were elbow extension angular velocity(X=34.7±8.1%), upper arm internal rotation angular velocity (X=13.3±9.8%), trunk twist (X=11.9±6.3%), translation of the thrower's c.m. (X=11.8±2.4%) and javelin distortion and recoil(X=9.0±6.7%). All remaining terms independently contributed less than 4% to javelin speed. For each throw, the aforementioned five terms accounted for over 80% of the javelin's release speed. However, the relative magnitudes of each term's percent contribution to javelin speed at release differed for the throws indicating possible technique variations among the athletes.

Determination of body segment masses and centers of mass using a force plate method in individuals of different morphology

It is unknown whether or not the daily swim training distances of master swimmers (MS) affect the observed changes in skeletal muscle mass (SM) and physical function commonly associated with the aging process. Twenty-two male MS aged 52-82 years were divided into two groups based upon training distance: High MS (>3000 meters swim/session and 4.1 times/week; n=11) and moderate MS (1500-2800 meters swim/session and 3.4 times/week; n=11). Eleven age- and body mass index-matched older (aged 56-80 years) men served as controls (AMC). Subjects who performed resistance training were excluded in this study. Muscle thickness (MTH) was measured by ultrasound at nine sites on the anterior/posterior aspects of the body (forearm, upper arm, trunk, thigh, and lower leg), and from this, total and segmental SM mass values were estimated. Thigh MTH (anterior:posterior mid-thigh, A50:P50) ratio was calculated to assess the site-specific thigh muscle loss. Straight and zigzag walking performance and maximum knee extension/flexion strength were also measured. Arm SM was greater for high MS and moderate MS than for AMC. Total SM index was higher for high MS than for moderate MS and AMC. A50:P50 ratio was greater for high MS than for AMC. Absolute and relative knee extension strength, but not flexion strength, was greater in high MS than in AMC. The A50:P50 ratio inversely correlated (p<0.05) with zigzag walking time, whereas relative knee extension strength positively correlated (p<0.05) with both straight and zigzag walking performance. Training distance in older MS may be an important factor for maintaining muscle mass and function in the aging process.

Experimental recommendations for estimating lower extremity loading based on joint and activity

This paper reports a study of the optimal release of men's and women's new and old rule javelins involving modeling, simulation, optimization (including sensitivity analysis), and simulation evaluation. Because of the lack of repro-ducibility in earlier results of two-dimensional flight simulation research, the paper presents a continuation of the two-dimensional model used previously. As expected, each javelin was found to have a different optimal release for a given individual, and the optimal release varied with the thrower's nominal release speed. A limited degree of simulation evaluation was achieved by comparison of the model and simulation results with measured throws. Within the constraints of measurement error, this tended to support both the adequacy of the two-dimensional model and the results of the simulations for such high standard throws. However, further experimental studies to quantify the angle of yaw (sideslip) in measured wind conditions are recommended to assess any changes needed to the two-dimensional model of javelin throwing and to determine the advisability of including this three-dimensional aspect of javelin release in future simulations.

We attempt to clarify the factors that regulate the propagation and structure of gravity currents through evaluation of idealized theoretical models along with two-dimensional numerical model simulations. In particular, we seek to reconcile research based on hydraulic theory for gravity currents evolving from a known initial state with analyses of gravity currents that are assumed to be at steady state, and to compare these approaches with both numerical simulations and laboratory experiments. The time-dependent shallow-water solution for a gravity current propagating in a channel of finite depth reveals that the flow must remain subcritical behind the leading edge of the current (in a framework relative to the head). This constraint requires that hf/d ≤ 0.347, where hf is the height of the front and d is the channel depth. Thus, in the lock-exchange problem, inviscid solutions corresponding to hf/d = 0.5 are unphysical, and the actual currents have depth ratios of less than one half near their leading edge and require dissipation or are not steady. We evaluate the relevance of Benjamin's (1968) well-known formula for the propagation of steady gravity currents and clarify discrepancies with other theoretical and observed results. From two-dimensional simulations with a frictionless lower surface, we find that Benjamin's idealized flow-force balance provides a good description of the gravity-current propagation. Including surface friction reduces the propagation speed because it produces dissipation within the cold pool. Although shallow-water theory over-estimates the propagation speed of the leading edge of cold fluid in the ‘dam-break’ problem, this discrepancy appears to arise from the lack of mixing across the current interface rather than from deficiencies in Benjamin's front condition. If an opposing flow restricts the propagation of a gravity current away from its source, we show that the propagation of the current relative to the free stream may be faster than predicted by Benjamin's formula. However, in these situations the front propagation remains dependent upon the specific source conditions and cannot be generalized.

Introduced in China in the late 1990s, Peripherally Inserted Central Catheters (PICCs) have undergone rapid development and are widely used to deliver chemotherapy for cancer treatment and to establish adult postoperative parenteral nutrition pathways (Zhong, 2007). The technologies and methods related to PICC insertion have also developed rapidly. The United States Infusion Nurses Society and Oncology Nurses Society have published a number of clinical nursing practice guidelines for vascular access devices (Alexander, 2011; Camp-Sorrell, 2011), which present the best practice evidence for multiple steps of the PICC insertion process, such as the selection and preparation of the puncture site and catheter insertion. Such guidelines aim to standardize the procedures, effectively utilize limited health resources, and protect the patients’ interests. The current PICC insertion procedure in our hospital was developed from experience-based standards and processes are mechanically executed. To address this practice problem, we conducted a project to explore how to effectively implement the best practice of PICC insertion in our hospital. Our hospital is a tertiary cancer care center, affiliated with Fudan University with approximately 400 PICC insertion cases per month. The vascular access care outpatient clinic is led by PICCs specialty nurses and currently staffed with 1 chief nurse, 5 full-time PICC insertion nurses, and 11 full-time point-of-care nurses. This clinic is also equipped with three vascular ultrasound systems. The PICO (Population, Intervention, Comparison, Outcome) question that guided the project was as follows: In patients receiving a PICC line insertion (P) how does use of best practice affect insertion procedures, (I) how does it compare to experience-based insertion procedures, (C) how does it affect patient outcomes and nursing outcomes (O)? Between October and December 2012, the following databases were systematically reviewed: The Joanna Briggs Institute Library (1998–2012), EMbase, Elsevier (1990 to present), Web of Knowledge, Ovid, China National Knowledge Infrastructure (CNKI, 1990–2011) and the Chinese Wanfang database. A Web-based review of relevant guideline websites and professional websites, including the National Guideline Clearinghouse (NGC) and the Registered Nurses' Association of Ontario (RNAO), were also conducted. Five PICCs insertion-related guidelines that were currently in use in the United States, the United Kingdom, and Canada (Alexander, 2011; Camp-Sorrell, 2011; O'Grady et al., 2011; Pratt et al., 2007; Registered Nurses' Association of Ontario, 2008) were obtained. The key terms used in this project included peripherally inserted central catheters or PICCs and best practice or ultraso* or modified Seldinger technique or insertion or chlorhexidine or maximum sterile barrier or catheter tip location and position or complications. Fudan University Evidence-based Nursing Center is one of the cooperation centers of Joanna Briggs Institute (JBI) so the JBI evidence grading system version 2010 in Chinese was used for appraisal (Yan Hu, 2012). When determining appropriate catheter length, a PICC insertion nurse should use a measuring tape to measure from the point of venipuncture, over the course of the selected venous pathway, across the shoulder to the right side of the sternal notch, and down to the third intercostal space (Level III; Camp-Sorrell, 2011; Claasz & Chorley, 2007). Two percent of chlorhexidine gluconate ethanol solution is recommended to disinfect the skin at the catheterization site (Level I; Camp-Sorrell, 2011; Registered Nurses’ Association of Ontario, 2008). During the PICC insertion process, a maximum sterile barrier should be established. The operators should wear masks, hats, sterile powder-free gloves, a sterile gown and spread large, sterile sheets; the patients should wear masks and hats, and their entire body should be covered with sterile sheets (Level I; Alexander, 2011; O'Grady et al., 2011; Pratt et al., 2007). Vascular ultrasound guidance combined with the modified Seldinger technique should be used to insert the PICC catheter into the upper arm, especially the right upper arm, which lead to improved puncture and catheterization success rates and reduced complications related to mechanical damages (Level I; Li, Yan, & Zhang, 2013; Zhang et al., 2011). The optimal position for the catheter tip is from the lower third of the superior vena cava to cavoatrial junction; however, the catheter tip should not enter the right atrium (Level I; Infusion Nurses Society, 2006; National Association for Vascular Access Networks, 1998). Markers for determining the optimal position of the PICC tip on chest X-ray films include the carina of the trachea, the right main bronchus angle, and the upper right edge of the heart shadow, and position 4 cm or two thoracic vertebrae below the carina of trachea are considered appropriate (Level III; Baskin, Jimenez, Cahill, Jawad, & Towbin, 2008; Liu, Zhao, & Wang, 2011; Mahlon & Yoon, 2007). When the PICC have been inserted to the predicted length, an ultrasound probe can be used to detect the jugular vein on the catheterization side to exclude the possibility that the catheter tip entered the jugular vein and to facilitate timely adjustment (Level II; Bullock-Corkhill, 2010; Schweickert et al., 2009). Vascular ultrasound system is recommended to distinguish arteries, veins and nerves or nerve bundles to prevent the accidental perforation of arteries or nerves (Level II; Jin, 2005). The steps of the PICC insertion procedure in our hospital were formed based on the nurses’ experiences. This situation was not conducive to establishing and implementing a best practice. In order to ensure the safety of patients and improve the quality of care, we needed to use the current, best scientific evidence that was available to guide our PICC insertion practices. Before applying the body of evidence to our practice, we formed the project team. The team was led by the nurse researcher, directed by the head nurse of the clinic and supported by the director of hospital nursing service department. The seven-member team ultimately included PICCs insertion nurses, the head nurse, the director of the nursing department, a diagnostic radiologist and an interventional radiologist. The process utilized for integrating the evidence into practice included five steps. A situational assessment and analysis was conducted prior to the clinical implementation of the evidence: (a) an assessment of hospital resources and facilities, current rules or processes, the staff workload, the use of related materials; (b) interviews were conducted with the head nurses and PICC insertion nurses related to attitudes toward the existing PICC insertion process, the practical difficulties expected for evidence implementation, and director's support for and attention to the process; (c) an assessment of the feasibility and complexity of the planned implementation of best evidence for PICC insertion in hospitals, with or without an increase in the workload of the PICC insertion nurses and the nurses’ acceptance of the practices. Based on the assessment of evidence from the literature and our existing procedure, supports or barriers were identified and analyzed, and strategies of maximum resources utilization and evidence-based implementation were developed. For example, the mark, which used to detect the PICC tip position in our hospital, was the count of the rib on X-ray images. It was quite different from the best evidence synthesized at the beginning of the project. Therefore, the recommended detection of the PICC tip position was one of the revised items in PICCs insertion procedure. Additional evidence-based changes were: The implementation of 2% chlorhexidine for disinfectants and a maximum sterile barrier for patients; the use of vascular ultrasound technology; the identification of artery, vein, nerve and the catheter migration into the jugular vein using vascular ultrasound. The vascular access management software was improved by adding information about the catheter tip location, the one-puncture success rate, the tube insertion success rate, and the incidence of complications during catheterization, such as primary catheter malposition. The preliminary investigation conducted before the evidence-based changes were implemented revealed that although the nurses had received the Shanghai Institute of Nursing PICC insertion competency certificate, their training had mainly focused on technical operations; the nurses lacked theoretical training, and their basic knowledge of evidence-based nursing was relatively weak. Before the evidence was implemented, PICC insertion nurses and managers who participated in this project were educated on the updated evidence related to PICCs, new PICC insertion process and relevant documentation requirements. A video demonstrating the new PICC insertion process was produced for training PICC insertion nurses. As a result, full preparation for the transition to the new, evidence-based PICC insertion practice was provided. After receiving permission from the hospital's institutional ethics review board, the PICC insertion checklist and newly revised PICC insertion process was implemented in clinical practice. Core team members were available to answer questions, address issues that arose during the implementation, and provide timely feedback and solutions. It was vital to build in structures and processes to ensure continued and appropriate use of the interventions. A PICC insertion checklist was developed to monitor the quality of PICC insertions conducted by the nurses. This documentation form included the patient ID number and patient identity verification and recorded all the steps according to the PICC insertion process and each item could be marked as “conform” or “did not conform.” The checklist was spot-checked and completed by the chief nurse on the unit. Meanwhile, case study meetings were organized to discuss prevention and treatment measures for common complications that arose during the catheterization processes. After the completion of the clinical implementation, the managers and all PICC insertion nurses met for a discussion and summary to determine areas for further improvement. The data for 867 patients who underwent PICC insertion in the vascular access care outpatient clinic was collected in July and August 2013 before the evidence-based practices were implemented. The period from October 2013 to February 2014 was the implementation phase for evidence-based PICC procedures. The data with 742 patients were recorded and then compared with those before the implementation of the evidence-based protocol. With the provision of additional education, the average knowledge score of nursing staff increased from 110.7 to 118.3 out of a possible total score of 120 on a PICC line insertion knowledge test designed by the team. As part of the education program, all five PICC insertion nurses were trained about PICC insertion updated knowledge about upper arm catheterization under ultrasound guidance combined with the modified-Seldinger technique. The implementation of this evidence-based intervention improved the quality of care in the vascular access outpatient care clinic, as reflected in the following patient outcome indicators: The percentage of patients who chose the upper arm instead of traditional forearm catheterization increased from 98.96% (858/867) before the implementation of evidence-based practices to 99.87% (741/742) after the implementation. The result of Fisher exact probability method showed the difference to be significant (p < .05). The PICC insertion nurses’ updated knowledge related to selection of the catheterization arm also improved patient outcomes. The results of the chi-square test indicated that the percentage of patients (81.4%, 604/742) whose PICC catheter tip reached the optimum position was significantly higher than that (75.78%, 657/867) before the changes (p < .05). Finally, implementing improvements in the methods for measuring the PICC catheter insertion in vitro improved the patient outcome of accurate targeting of the PICC catheter tip in the lower 1/3 of the superior vena cava or cavoatrial junction, and not into the right atrium. Before the changes were implemented, the nurses adjusted the catheter in 19.39% (32/165) cases with the PICC catheter tip positioned too deep. The percentage increased to 47.37% (45/95) cases after the evidence-based practice change. This finding was statistically significant (p < .001). The results showed that the ability of nurses to detect the PICC tip position on X-ray image significantly improved when the catheter tip was positioned too deep. One difficulty in the implementation of evidence-based practices is the normalization of such practices. In addition to training, an effective way to continuously strengthen practices is to integrate them into the daily work of nursing. In this study, we revised the PICC insertion procedures and conducted training to integrate evidence-based practices into the operational procedures. The operational procedures could change the behaviors of the nurses and ultimately enable them to achieve mastery of evidence in their daily work while normalizing the new practices. Continuous strengthening of the evidence and monitoring of implementation measures are key factors in normalizing best practices (Aitken et al., 2011). The primary role of monitoring is to ensure the effective implementation of the evidence-based measures, and the normalization of the changes. In addition, continuous monitoring could reveal whether the current measures required modification or whether new measures needed to be added. The implementation of evidence-based innovations in this project was monitored by the chief nurse using the PICC insertion checklist. During the group discussion on evidence implementation that was part of this project, the nurse researcher and PICC insertion nurses found that some barriers influenced the adherence to evidence-based PICC procedure, such as the inconsistencies between what “they knew” and what “they do.” The key to overcoming this barrier and reduce these inconsistencies was to allow the learned knowledge to be effectively applied in clinical practice. The evidence informs the practitioners about what to do, but the specific procedures still need to be further refined and developed by researchers and practitioners according to specific clinical scenarios, including details pertaining to time, frequency, objects, methods, approaches, recording, and feedback. It is important to progress from experience-based practice to evidence-based practice, and use scientific evidence to guide our practices, to ensure the safety of our patients and improve quality of our care. During the best practices implementation process, it was essential to take full advantage of the functional roles played by researchers, care managers and PICC insertion nurses; apply effective strategies consistent with the clinical context; and make efforts to apply the evidence to daily work to ensure effective implementation. The outcomes of the implementation project were reported to the nurses in the clinic, the IV-team members, and the nursing quality supervisors in our hospital. The implementation protocol was introduced across the hospitals affiliated with Fudan University. Project results were disseminated through oral presentations at four regional and international doctoral student forums and oncology nursing conference. The best evidence on PICCs insertion developed in this project will be published on the website of Fudan University Evidence-based Nursing Center.

Muscular strength, including dynamic (isotonic) and static (isometric) forms, is critical for athletic performance and is commonly assessed through maximal effort tests. The javelin throw differs from other throwing events due to its higher release velocity and very short execution time, requiring athletes to generate maximal force rapidly. Consequently, event-specific training is essential. The purpose of this study was to examine the relationship between upper arm strength and throwing velocity in university-level male javelin throwers. Eight male university javelin throwers (mean age=21.50±1.20 years) performed the seated medicine ball throw (5-kg) to assess upper arm strength and three maximal javelin throws to measure throwing velocity. The highest score from each test was used for analysis. Pearson’s correlation examined the relationship between upper arm strength and throwing velocity (p&lt;0.05). University-level male javelin throwers demonstrated a mean seated medicine ball throw of 2.88±0.35 m and a mean throwing velocity of 87.78±1.94 km/hour. A Pearson correlation showed a very strong positive relationship between upper arm strength and javelin throwing velocity, r (8)=0.916, p=0.001. The findings indicate that greater upper arm strength is strongly associated with higher javelin throwing velocity. This underscores the importance of upper arm strength in javelin performance, while also suggesting that other factors may contribute to throwing velocity and merit further investigation.

Single frequency bioelectrical impedance analysis is an inexpensive, quickand painless means of estimating body composition. However, current approachesto estimating body composition from segment resistivity have some drawbacks.The purpose of this study was to overcome these limitations by developing abetter model of the relationship between resistivity and body composition. Athree-compartment model of body mass and body segment resistivity is presentedand calibrated to predict %Fat estimated by underwater weighing. The subjectpopulation from which the data were obtained was heterogeneous. Both sexeswere represented, as were a range of ages (21-44 years), ethnic backgrounds,body masses (47.0-129.0 kg) and body compositions (%Fat = 8.7-50.7%).Based on resistivity measurements from the upper arm and upper leg, andmeasurements of subject height and weight, the model predicted %Fat witherrors comparable to those reported for other methods based on segmentalresistivity. All the terms in the calibrated model represented a physicalcomponent of the body and show reasonable agreement with resistivity measuredin tissue samples. In short, predicting %Fat from resistivity of the proximalarm and leg segments compares favourably with other methods based on segmentresistivity.

In this paper, we have developed a motion capture method based on data collected by MYO armband. The method can be applied on any healthy operator wearing two MYO armbands on both upper and lower arms, respectively. The first MYO armband is worn near the centre of the operator's upper arm, the other is worn near the centre of the forearm. MYO armband has built-in eight bioelectrical sensors as well as a 9-axis IMU. The IMU sensors of the MYO are used to detect and reconstruct physical motion of shoulder and elbow joints, while the bioelectrical sensors are used to collect electromyography (EMG) signals associated with wrist motion. This hybrid method enable us to fully capture the motion of the 6-DOF (degree of freedom) of the arm. To test the proposed method, hardware-in-loop simulations studies are performed, with both physiological and physical signals received and processed in MATLAB/Simulink via a low-power bluetooth interface. Results demonstrate the validness and effectiveness of the proposed method.

PURPOSE: The use of Kinesio Tape (KT) is gaining popularity throughout the allied health professions and claims to have several benefits such as increasing blood and lymphatic flow, strengthening of weak muscles, decreasing pain, increasing proprioception and repositioning of subluxed joints. However, little to no scientific research has been performed to validate any of these claims. One claim is that KT increases blood flow to the taped area in order to help expedite the healing process. Thus, the purpose of this study was to determine if blood flow changes occurred in the upper arm with KT application compared to regular athletic tape (AT). METHODS: Ten healthy subjects (age: 21.1 ± 1.6 yrs; height: 172.2 ± 13.4 cm; mass: 72.3 ± 24.0 kg) volunteered for the study. All subjects completed two experimental trials (KT or AT) on separate days performed in a counter-balanced order. Each experimental trial consisted of three sessions and an exercise regimen. The first session was a 20 minute baseline period (seated-rest, no tape), the second session consisted of a 20 minute period after the application of tape (seated-rest, AT or KT). A submaximal exercise regimen (standing bicep curls, 3 sets × 10 reps with a pre-determined dumbbell weight with a one-minute rest between sets) followed session two. Each subject's dumbbell weight was determined in an orientation visit, where they chose a weight in which they could perform 3 sets × 10 reps with fatigue occurring at the end of the third set. Finally, the third session consisted of a 20 minute recovery period following the exercise regimen (seated-rest, AT or KT). During the experimental sessions, skin blood flow was measured continuously via a LASER Doppler probe adhered over the biceps brachii. Skin blood flow data were expressed as a percent change from the baseline value and were not reported during the exercise session due to motion artifacts. A two-way (condition × time) ANOVA with repeated measures on both factors was used to test for statistical significance. RESULTS: There was no condition X time interaction or main effect for condition; however there was a main effect for time (F(1.3,9.3) = 4.34, P = 0.05). Pairwise comparisons using a LSD adjustment showed that skin blood flow was significantly lower (−4.9%) after tape application compared to baseline (P = 0.05). In addition, there was a tendency for skin blood flow to be greater (36.0 %) during the post-exercise recovery period compared to baseline (P = 0.06) (See Figure 1). Conclusion: Our results show that there was no difference in blood flow with either tape or conditions. Practical Application: Using KT for increasing blood flow for rehabilitating or strengthening muscles of athletes may not be more beneficial than regular AT. It appears that the application of either tape may change blood flow to the targeted area, but most likely as a result of prior exercise.

Data about effects of exercise training in adolescents with intellectual disability (ID) are very limited. This study investigated the effect of 2 different frequencies of the same intensity and total training volume of combined exercise training on indices of body composition, physical fitness, and lipid profile in overweight and obese adolescents with ID. A total of 45 overweight and obese adolescents with ID aged 14-22 years with a total IQ 45-70 received combined exercise training 3 times a week (CET3) for 30 sessions (10 weeks; n = 15), twice a week (CET2) for 30 sessions (15 weeks; n = 15), or no training (10 weeks; n = 15). Groups were matched for age, sex, and education form. Before and after the intervention period, indices of body composition, physical fitness and lipid profile have been evaluated. Compared to the control group, CET3 resulted in a significant improvement of physical fitness, obesity indices, and lipid profile of the participants. Comparing CET2 with CET3, no significantly different evolutions were noticed, except for lower limb strength in favor of exercising 3 times a week. In conclusion, exercising 2 times a week, which is more feasible and practical for participants and guidance, has the same health beneficial effects as 3 times per week in overweight and obese adolescents with ID in short-term training.

Three-phase fluid migration with solubilities in a two-dimensional basin simulation model

We introduce a new fully automated breast mass segmentation method from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). The method is based on globally optimal inference in a continuous space (GOCS) using a shape prior computed from a semantic segmentation produced by a deep learning (DL) model. We propose this approach because the limited amount of annotated training samples does not allow the implementation of a robust DL model that could produce accurate segmentation results on its own. Furthermore, GOCS does not need precise initialisation compared to locally optimal methods on a continuous space (e.g., Mumford-Shah based level set methods); also, GOCS has smaller memory complexity compared to globally optimal inference on a discrete space (e.g., graph cuts). Experimental results show that the proposed method produces the current state-of-the-art mass segmentation (from DCEMRI) results, achieving a mean Dice coefficient of 0.77 for the test set.

Fibrous hamartoma of infancy (FHI) is a rare benign soft tissue lesion of infants and young children. It usually occurs within the first 2years of life at the superficial layer of the axilla, trunk, upper arm, and external genitalia. FHI in the central nervous system (CNS) is extremely rare. So far, only two spinal cord FHI cases have been reported. We present a case of a 1-month-old girl who presented with a skin dimple in the coccygeal area. Her MRI showed a substantial intramedullary mass in the thoracolumbar area with a sacral soft tissue mass and a track between the skin lesion to the coccygeal tip. Her normal neurological status halted immediate surgical resection. A skin lesion biopsy was first performed, revealing limited information with no malignant cells. A short-term follow-up was performed until the intramedullary mass had enlarged on the 5-month follow-up MRI. Based on the frozen biopsy result of benign to low-grade spindle cell mesenchymal tumor, subtotal resection of the mass was done, minimizing damage to the functioning neural tissue. Both the skin lesion and the intramedullary mass were diagnosed as FHI. Postoperative 5.5-year follow-up MRI revealed minimal size change of the residual mass. Despite being diagnosed with a neurogenic bladder, the patient maintained her ability to void spontaneously, managed infrequent UTIs, and continued toilet training, all while demonstrating good mobility and no motor weakness. This case is unique because the lesion resembled the secondary neurulation structures, such as the conus and the filum, along with a related congenital anomaly of the dimple.