Search

This study aimed to investigate the characteristics of lumbar lordosis angle and sacral slope angle during trunk extension in ballet dancers. The participants were 13 healthy female ballet dancers (ballet group) and 15 women with no ballet experience (non-ballet group). Lumbar lordosis and sacral slope angle in standing and maximum trunk extension were measured using lateral X-ray images of the lumbar spine. The amount of change in lumbar lordosis and sacral slope angle between standing and maximum trunk extension were calculated and compared between the two groups. The lumbar lordosis angle in static standing of the ballet group was lower than that of the non-ballet group. The ballet group showed a higher amount of change in lumbar lordosis angle and a lower amount of change in sacral slope angle than those of the non-ballet group. The extent of lumbar lordosis is suggested to increase from the standing to the maximum trunk extension position, which is a characteristic of the spinal motion of ballet dancers. [ABSTRACT FROM AUTHOR]

This study examined the impact of the COVID-19 pandemic on men's ice hockey in Kanagawa prefecture. We investigated the number and type of penalties and injuries that occurred in men's ice hockey league games in Kanagawa between September 2018 and March 2023. In total, data from 734 games were analyzed, and data were compared between seasons. The average number of penalties per game was 5.93 in the 2018-2019 season, 5.66 in the 2019-2020 season, 4.96 in 2020-2021, and 4.40 in 2021-2022, 4.64 in the 2022-2023 season, indicating that the number of penalties decreased during the COVID-19 pandemic. However, the number of penalties involving the stick increased. Injuries during games also increased during the COVID-19 pandemic, from 0 in the 20182019 (175 games) and 2019-2020 (191 games) seasons to 1 case in the 2020-2021 (73 games) season, 6 cases in the 2021-2022 (119 games) season and 2 cases in the 2022-2023 (176 games) season. The increased number of injuries observed may have been due to the closure of ice rinks by the state of emergency, which restricted on-ice training. As players avoided contact to prevent the spread of COVID-19, penalties caused by contact play decreased, whereas those involving sticks increased. [ABSTRACT FROM AUTHOR]

[Purpose] This study aimed to clarify the changes in the scapulothoracic joint and upper trunk angles and postural control during right-left hand-behind-back (HBB) movement. [Participants and Methods] The participants were 20 healthy right-handed men. We measured the HBB movement while standing using a three-dimensional motion capture system. Changes in the internal rotation angle of the scapulothoracic joint, upper trunk rotation angle, and center of pressure (COP) were examined to assess potential right-left differences between the analyzed positions. [Results] As the thumb touched the buttocks, upper trunk contralateral and scapulothoracic joint internal rotations were observed and the COP on the non-HBB side was significantly displaced laterally. There were no right-left differences in the changes between the analyzed positions for all measures. [Conclusion] Upper trunk contralateral rotation and postural control were conducted without right-left differences during HBB movement. These results suggest that upper trunk movement and standing postural control are involved in HBB movement. Therefore, it is useful to focus on the scapulothoracic joint angle, upper trunk rotation angle, and standing postural control during physical therapy evaluation and treatment with HBB movement., Competing Interests: The authors have no conflicts of interest to declare., (2024©by the Society of Physical Therapy Science. Published by IPEC Inc.)

Background: Few studies have investigated the kinematics after reverse total shoulder arthroplasty (RTSA). This study aimed to compare the shoulder kinematics in RTSA patients during shoulder abduction on the scapular plane with and without a load and yield information regarding the function of stabilizing the joints against gravity for the functional assessment of the shoulder after RTSA, which could lead to changes in postoperative rehabilitation treatment., Methods: Twenty RTSA patients (7 men, 13 women; mean age: 78.1 [64-90] years) were examined. First, active shoulder abduction in the scapular plane was captured using single-plane fluoroscopic X-ray images. Imaging was performed by stipulating that one shoulder abduction cycle should be completed in 6 s. Two trials were conducted: one under a load equivalent to 2% of body weight and one without a load. Next, a three-dimensional (3D) model of each humeral and scapular component was matched to the silhouette of the fluoroscopic image to estimate the 3D dynamics. By using the 3D dynamic model obtained, the kinematics of the glenosphere and humeral implant were calculated relative to the shoulder abduction angle on the scapular plane and were compared between groups with and without a load. A one-way analysis of variance and a post hoc paired t-test with a statistical significance level of 0.05 were performed., Results: The humeral internal rotation decreased with a load at shoulder abduction between 40° and 90° on the scapular plane (P < 0.01, effect size: 0.15). No significant differences in scapular upward rotation (P = 0.57, effect size: 0.022), external rotation (P = 0.83, effect size: 0.0083) and posterior tilting (P = 0.74, effect size: 0.013) were observed between groups with and without a load. The main effect was not observed with and without a load (P = 0.86, effect size: 0.0072). However, the scapulohumeral rhythm was significantly greater without a load during shoulder joint abduction between 40° and 60° on the scapular plane., Conclusion: In RTSA patients, the glenohumeral joint was less internally rotated, and the scapulohumeral rhythm decreased under loaded conditions. It was stabilized against the load through the mechanical advantage of the deltoid muscle and other muscles., (© 2023. Arthroplasty Society in Asia.)

Background: It is often assumed that body posture, standing vs. supine, changes shoulder muscle activation and range of motion, but these altered shoulder mechanics have not been objectively assessed. We expected the supine posture might facilitate scapular rotation and change subacromial pressure. The purpose of this study is to evaluate the influence of body posture on shoulder kinematics during arm elevation., Methods: Ten males and eight females with a mean age of 33 years participated in this study. Shoulder kinematics were assessed during scapular plane elevation in the standing and supine postures by using single-plane fluoroscopic images. Kinematics were measured using 3-dimensional to 2-dimensional model-image registration techniques: matching the 3-dimensional bone model derived from computed tomography onto each fluoroscopic image. Glenohumeral superior/inferior translation, acromiohumeral distance, and scapular rotations were compared between the postures. The effect of sex also was evaluated., Results: With the arm at the side position, the humeral head in the supine posture was located 0.5 mm superior compared to the standing posture ( P  < .001). During humeral elevation, the humeral head significantly shifted more inferiorly in the supine posture than in standing; the biggest mean difference was 0.6 mm, P  = .003. But acromiohumeral distance during elevation was not significantly affected by the body posture ( P  = .05). Scapular upward rotation and posterior tilt were significantly different between the postures ( P  < .001). Sex had statistically significant, but quantitatively small, effects on shoulder kinematics., Conclusions: Body postures affect shoulder kinematics during humeral elevation. This knowledge will be useful to optimize rehabilitation exercises and for diagnostic insight., (© 2021 The Authors.)

Regioselective difunctionalization of two different C-H bonds in one pot using a three-component coupling reaction is described. The reaction order is important for controlling the reactivity and regioselectivity, and the first silylation promotes the second borylation. The introduced formyl, silyl, and boryl functional groups could be independently converted to other functional groups, and the substitution pattern for the resulting benzenes is difficult to access by conventional methods.

Despite the utility of 9-silafluorenes as functional materials and as building blocks, methods for efficient functionalization of their backbone are rare, probably because of the presence of easily cleavable C-Si bonds. Although controlling the regioselectivity of iridium-catalyzed direct borylation of C-H bonds is difficult, we found that bromination and nitration of 2-methoxy-9-silafluorene under mild conditions occurred predominantly at the electron-rich position. The resulting product having methoxy and bromo groups can be utilized as a building block for the synthesis of unsymmetrically substituted 9-silafluorene-containing π-conjugated molecules.

Sleep disordered breathing (SDB) was more prevalent in adolescent athletes than expected, and several potential warning signs related to autonomic nerve activity appeared in SDB athletes. SDB screening may prevent associated downstream risks in the future. http://ow.ly/GQqK30nGm8r., Competing Interests: Conflict of interest: Y. Iso has nothing to disclose. Conflict of interest: H. Kitai has nothing to disclose. Conflict of interest: E. Kyuno has nothing to disclose. Conflict of interest: F. Tsunoda has nothing to disclose. Conflict of interest: N. Nishinaka has nothing to disclose. Conflict of interest: M. Funato has nothing to disclose. Conflict of interest: E. Nishimura has nothing to disclose. Conflict of interest: S. Akihiro has nothing to disclose. Conflict of interest: H. Tanuma has nothing to disclose. Conflict of interest: T. Yonechi has nothing to disclose. Conflict of interest: E. Geshi has nothing to disclose. Conflict of interest: T. Sambe has nothing to disclose. Conflict of interest: H. Suzuki has nothing to disclose.

Case: A 49-year-old man presented with apprehension of a repeat dislocation after a left shoulder dislocation, which was accompanied by pain and restricted active range of motion of the shoulder. We performed an arthroscopic Bankart repair as well as an arthroscopic superior capsular reconstruction (ASCR) with fascia lata for the irreparable massive rotator cuff tear. Two years postoperatively, there was no shoulder pain or repeat dislocation; the range of motion had improved., Conclusion: We regard ASCR in combination with a Bankart repair as a useful treatment for recurrent shoulder dislocation that is accompanied by an irreparable massive rotator cuff tear.

An iridium-catalyzed regioselective sequential silylation and borylation of heteroarenes was developed, which represents a rare example of unsymmetrical intermolecular C-H bond difunctionalization through the introduction of two different functionalities during a one-pot transformation. Although the substrate scope for the dehydrogenative silylation of heteroarenes has been limited mainly to electron-rich five-membered rings, the current reaction proceeds with both electron-rich and electron-deficient heteroarenes with the aid of heteroatom-directing C-H bond activation. The regioselectivity of the second borylation was controlled by both steric factors and the electronic effect of the silyl group installed in the first step. In combination with the classic cross-coupling reaction, this method provides rapid access to multisubstituted heteroarenes., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

While cyclopropanes have been explored as synthetically valuable building blocks, their transformation without conjugated substituents or directly substituted heteroatoms remains challenging. The current study describes the iridium-catalysed ring-opening hydrosilylation of cyclopropanes. A nitrogen-based directing group was found to control the reactivity of iridium active species as well as the regiochemistry of carbon-carbon bond cleavage and hydrosilylation.

Background: Advanced-stage osteochondritis dissecans of the capitellum affecting the lateral wall may result in osteoarthritis, and suitable treatment is needed to avoid permanent deformation and impaired function. We aimed to assess postoperative outcomes of costal osteochondral autograft for treatment of this condition., Methods: We included 22 young overhead athletes (mean age, 13.9 years) with advanced osteochondritis dissecans of the humeral capitellum who underwent costal osteochondral autograft. All patients had elbow pain and wide-range articular cartilage lesions. We evaluated clinical and radiographic outcomes at a mean follow-up of 27 months (range, 12-77 months)., Results: All patients achieved rapid functional improvement and returned to their former sports activity levels. The baseball players were able to play catch within 62 to 164 days (mean, 107 days) and returned to full pitching activity within 123 to 339 days (mean, 226 days). We assessed mean elbow function by the clinical rating system of Timmerman and Andrews and the Japanese Orthopaedic Association sports score; the scores improved from 121.5 and 53.7 points preoperatively to 169.2 points and 86.1 points, respectively, at the time of follow-up. Four patients required additional minor surgical procedures, including screw removal, loose body removal, and shaving off of spur formation. No patient showed obvious radiographic changes of osteoarthritis. All patients were satisfied with the final outcomes and had good functional recovery., Conclusion: Costal osteochondral autograft gave satisfactory results for advanced osteochondritis dissecans of the humeral capitellum with extensive lesions affecting the lateral wall., (Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Radiographic examination of the anterior part of the shoulder includes routine anterior-posterior imaging that enables easy visualization of traumatic injuries and true anterior-posterior imaging that enables the visualization of intra-articular injuries. The X-ray incident angle of true anterior-posterior imaging is affected by physique and posture. However, in many reports, the angle is uniformly determined on the basis of the antero-posterior axis and the horizontal plane. We previously reported that the glenohumeral joint can be visualized with good reproducibility by establishing a reference line on the basis of three points on the body as indicators, namely the posterior view of the under-surface of the acromion, the coracoid process, and the inferior angle of the scapula. However, visualizing the undersurface of the acromion using physical indicators to set the angle for imaging remains problematic. In previous reports, the angle was consistently set at 20° to the horizontal plane, regardless of physique or posture, which resulted in poor reproducibility. After examining the imaging techniques described in previous reports, we describe here an imaging technique using a reference line based on indicators on the surface of the scapula that enables the glenohumeral joint and the undersurface of the acromion to be visualized with good reproducibility.

Scapula-45 is an original roentogenographical technique to clarify objectively the function of the rotator cuff and scapulothoracic joint. This examination enables assessment of the function of the rotator cuff and scapulothoracic joint utilizing the radiographs of the glenohumeral joint. However, in the former technique, it was difficult for the technician to properly align the patient for the view of the true glenohumeral joint because of the individual postural difference of the patients, such as kyphosis. In the present study, we reported a new technique with the use of the acromion, coracoid process, and inferior angle of the scapula as a landmark to obtain the consistent radiographs of the glenohumeral joint.

Background: Surgical treatments have been selected to treat advanced osteochondritis dissecans (OCD) of the humeral capitellum., Purpose: To evaluate the clinical results of surgical treatments for advanced capitellar OCD lesion and to clarify problems of poor clinical results., Methods: Cases were reviewed for 27 patients with advanced OCD lesions treated operatively. All patients were male baseball players, with a mean of 13.3 years at the time of surgery. Drilling only was performed for 3 patients, fragment fixation for 13 patients, and removal of the detached fragment with drilling for four patients. Since 2004, reconstruction of the articular surface with use of osteochondral autograft from the rib has been performed for 7 patients with osteochondral defect. Mean follow-up was 37.4 months. Follow-up assessment included modified elbow rating system, evaluation of radiographs, and return to sports., Results: Mean subjective score improved significantly from 70 to 96 postoperatively. Mean objective score improved significantly 71 to 81 postoperatively. A postoperative return to baseball was achieved by 25 patients. On the final radiographs, 4 patients showed flattening of >70% of the capitellum or degenerative changes, including insufficient remodeling of the lateral margin of the capitellum. Although patients could return to baseball, postoperative total arc of the elbow was decreased compared with the preoperative total arc., Conclusion: Surgical treatments were useful to restore advanced OCD lesions. Our results suggest that reconstruction of the lateral margin of the capitellum is important for achieving good clinical results., Level of Evidence: Level 4.

Background: Spontaneous healing potential and progression of osteochondritis dissecans of the capitellum have been unclear., Hypothesis: Healing potential is high in the early stage of osteochondritis dissecans and low in the advanced stage., Study Design: Case series; Level of evidence, 4., Methods: This retrospective study examines 39 patients with osteochondritis dissecans of the capitellum who were treated conservatively. All patients were baseball players (mean age, 12.8 years). After initial examination, all patients were advised to stop heavy use of the elbow. Physical and radiographic examinations were regularly performed and assessed. Mean duration of follow-up was 14.4 months., Results: Early-stage lesions were present in 30 patients, while 9 patients were diagnosed with advanced lesions. Open capitellar growth plates were observed in 17 patients, and closed capitellar growth plates were seen in 22 patients. On final radiography, 25 of 30 early-stage lesions were assessed as healed. However, only 1 of 9 advanced-stage lesions was assessed as healed. The remaining 8 advanced lesions were unimproved or progressed. Healing of lesions was seen in 16 of 17 patients with an open growth plate and in 11 of 22 patients with a closed growth plate, representing a significant difference between patients with open and closed growth plates (P < .05)., Conclusion: Spontaneous healing potential of osteochondritis dissecans in early lesions, especially in patients with open capitellar growth plates, appears high, and nonoperative treatment is appropriate. Conversely, healing potential is extremely low in advanced osteochondritis dissecans lesions. Surgical intervention is recommended to achieve lesion healing in advanced cases.

Scapulohumeral rhythm (SHR) provides insight to neuromuscular control and fundamental biomechanics of the shoulder. This rhythm often is disrupted in pathologic shoulders. As the first step, we sought to quantify SHR in healthy subjects for diagnostic assessment of shoulder function. Ten healthy shoulders were studied. Three-dimensional models of the humerus and scapula were created from computed tomography scans. Dynamic shoulder motion was recorded by use of single-plane fluoroscopy during arm abduction with 0-kg and 3-kg handheld loads. Shoulder kinematics were quantified by use of model-based 3-dimensional-to-2-dimensional registration techniques. SHR decreased (more scapular motion) with increasing abduction. With a 3-kg load, scapulothoracic motion was significantly reduced through the range of 35 degrees to 45 degrees of glenohumeral motion. Muscular stabilization of the scapula increased with external loading, as shown by decreased SHR during early lifting. Dynamic scapular stabilization provides a critical platform for upper extremity activity.

The purpose of this study was to investigate glenohumeral translation in-vivo during active shoulder abduction in the scapular plane. Three-dimensional (3D) models of 9 shoulders were created from CT scans. Fluoroscopic views aligned to the plane of the scapula were recorded during active arm abduction with neutral rotation. 3D motions were determined using model-based 3D-to-two-dimensional (2D) registration. Humeral translation was referenced to the glenoid center in the superior/inferior direction. The humerus moved an average of 1.7 mm superior with arm abduction, from an inferior location to the glenoid center. The humeral head was centered within 1 mm from the glenoid center above 80 degrees abduction. Variability in glenohumeral translation between shoulders decreased significantly from initial to final arm abduction. Our findings agree with some authors' observations of inferior-to-central translation of the humerus and behavior as a congruent ball and socket. We believe this information will help improve the understanding of shoulder function.

Background: Fractures of the proximal humerus are common and the repair of displaced fractures generally requires an operative approach. In elderly patients, osteoporosis makes internal fixation problematic and frequently contributes to failed fixation and poor clinical results. We have developed a new intramedullary nail (pin lock nail) for the repair of surgical neck fractures of the proximal humerus in patients with osteoporotic bones. A retrospective review is presented of the cases of 19 elderly patients with two-part or three-part fractures of the proximal humerus treated using the pin lock nail., Methods: We treated 19 elderly patients with a mean age of 70.5 years. There were 13 two-part surgical neck fractures, 3 two-part surgical neck fractures with non-displaced greater tuberosity fracture, and 3 three-part surgical neck fractures with greater tuberosity fracture. All fractures were treated using the pin lock nail. Clinical results were evaluated using the Japanese Orthopaedic Association score at the last follow-up examination. On radiographic evaluation, duration to bone union of the fracture, backing out of the pin and screw, penetration of the proximal pin, and varus angulations of the humeral neck were examined., Results: Mean duration of follow-up was 14 months (range 6-54 months). All fractures had united at an average of 3.3 months after surgery. No backing out of the pin and screw or penetration of the proximal locking pin was seen at the time of last follow-up. Thirteen of the 16 patients had no or minimal varus angulations of the humeral neck (< or =10 degrees). The mean overall JOA score was 84.3 points (range 65.5-100)., Conclusions: Our data show that using the pin lock nail for the treatment of two-part and three-part humeral fractures is a reliable procedure, providing good results with careful postoperative management.

Most of the neurogenesis take place during the embryonic stage; the genes expressed predominantly in this stage may play important roles in the control of development of the central nervous system. Using a differential display method, we identified the novel rat gene, brain development-related molecule 2 (Bdm2), that is expressed more abundantly in the embryonic brain than in the adult brain. Full-length Bdm2 cDNA consists of 1842 base pairs (bp) and contains an open reading frame of 1260 bp. Northern blot analysis demonstrated that Bdm2 was strongly expressed in the late embryonic brain and was still detected at lower levels in an early postnatal period; in adults, Bdm2 mRNA was decreased to an undetectable level in brain, though the expression of this mRNA was revealed in other tissues. Level of Bdm2 mRNA was maintained during neuronal differentiation of mouse embryonal carcinoma cell P19, but decreased during the differentiation to glial and unidentified non-neuronal cells. In situ hybridization study demonstrated the wide distribution of Bdm2 mRNA in the embryonic brain; in the adult brain, the hybridization signals became more restricted to the hippocampus, olfactory bulb, cerebellum, and neocortex, almost coinciding with the regions where nascent and immature neurons are present. Thus, it appears likely that Bdm2 encodes a protein that is involved in both the regulation of growth of undifferentiated neural cells and the terminal differentiation of neuronal cells.

Postnatal development, such as synapse refinement, is necessary for the establishment of a mature and functional central nervous system (CNS). Using differential display analysis, we identified a novel gene, termed Bdm1, that is more abundantly expressed in the adult brain than in the embryonic brain. The full-length Bdm1 cDNA is 2718 base pairs long and contains an open reading frame of 1059 base pairs encoding a 38-kDa protein. Northern blot analysis revealed that expression of Bdm1 mRNA in the brain was weak on embryonic days and increased in the early postnatal period. Bdm1 mRNA was significantly expressed in the brain and heart, but there was no or little expression in other tissues. During the differentiation of mouse carcinoma cells P19 to neuron-like cells by retinoic acid, Bdm1 mRNA was up-regulated almost parallel to neurofilament mRNA. Expression of Bdm1 mRNA was observed appreciably in PC12 cells after neuronal differentiation but not in the nonneural cell lines examined. In situ hybridization demonstrated that Bdm1 was expressed widely in the olfactory bulb, cerebral cortex, hippocampus, cerebellum, thalamus, and medulla oblongata. Taken together, these data suggest that Bdm1 gene plays a role in the early postnatal development and function of neuronal cells., (Copyright 1999 Elsevier Science B.V.)