Search Results (9)

Background/Objectives: Overhead athletes, including swimmers, are prone to shoulder adaptations and pathologies, such as scapular dyskinesis (SD) and glenohumeral internal rotation deficit (GIRD). While SD has been extensively studied in various overhead sports, its prevalence and clinical implications in swimmers remain unclear. This study aims to evaluate static scapular asymmetries (SAs), defined as differences in the observed position of the scapulae at rest or in a fixed position, in young elite swimmers and compare these findings with functional scapular dyskinesis (SD) tests, which assess alterations in scapular motion patterns during arm movement. It also assesses potential relationships between SA and SD. Methods: A cohort of 661 young elite swimmers (344 males, 317 females) was assessed during the National Young Swimming Championships. Scapular asymmetries were measured in two positions: at rest and at 90° abduction with internal rotation. The measurements included the following: (1) dHeight: Difference in superomedial scapular angle height from the C7 spinal process; (2) dDistance: Difference in the distance of the superomedial scapular angle from the body midline; (3) dAngle: Angular deviation of the medial scapular border from the plumb line, assessed using a goniometer. The presence of scapular dyskinesis (SD) was determined using a functional test, and SA findings were compared with SD results. Statistical analyses included ANOVA and chi-square tests, with significance set at p < 0.05. Results: Scapular asymmetries were observed in 3.63% to 15.43% of swimmers, with no significant associations with age, gender, BMI, training years, or swimming characteristics (p > 0.05). A significant difference was observed between dominant limb and scapular height in abduction (p < 0.05). In position 1 (resting position), SA was significantly more prevalent in swimmers without SD (p < 0.001 for dHeight, p = 0.016 for dDistance). In position 2 (abduction), SA was significantly associated with SD-negative subjects in dAngle (p = 0.014) and dDistance (p = 0.02), while dHeight was not significant (p > 0.05). These findings suggest that static scapular asymmetries do not necessarily correlate with dynamic scapular dysfunction (SD), and, indeed, a negative correlation was observed where SA was significantly more prevalent in swimmers without SD in several measures (position 1, p < 0.001 for dHeight and p = 0.016 for dDistance; position 2, p = 0.014 for dAngle and p = 0.02 for dDistance). Conclusions: Young elite swimmers exhibit a relatively symmetrical scapular positioning, with scapular asymmetries potentially representing normal adaptations rather than pathological findings. The lack of positive correlation between SA and SD, and the higher prevalence of SA in SD-negative subjects, suggests the need for caution when interpreting static scapular assessments in swimmers as SA may reflect sport-specific adaptations rather than pathology. Full article

Background and Objectives: The aim of this study was to investigate the relationship between the position of the humeral head relative to the glenoid and the occurrence of iatrogenic surgical neck fractures of the humerus during anterior glenohumeral dislocation reductions. Materials and Methods: Patients with first-time anterior shoulder dislocations without generalized joint hyperlaxity were included. The humeral head displacement ratio was calculated as the distance between the medial border of the humeral head and the anterior glenoid rim divided by the diameter of the humeral head. Demographic data, concomitant tuberculum majus fractures, and the deltoid tuberosity index were recorded. Patients were divided into three groups: Group 1 (iatrogenic fracture development during closed reduction (CR)), Group 2 (failed CR), and Group 3 (successful reduction without iatrogenic fracture). Complicated dislocations were included in Groups 1 and 2, while uncomplicated dislocations were those in Group 3. Results: The study included 89 patients with a mean age of 46.44 ± 19.02 years (64 males, 25 females). Concomitant tuberculum majus fractures occurred in 37 (41.6%) cases. Iatrogenic surgical neck fractures occurred in 10 patients (Group 1), and CR was unsuccessful in 8 patients (Group 2), totaling 18 cases of complicated dislocations. Reduction without iatrogenic fracture was achieved in 71 cases (Group 3). The mean humeral head displacement ratio was higher in the complex dislocation group (92.91 ± 15.34 vs. 75.01 ± 13.80; p < 0.001). Complicated dislocations were more frequent in patients with tuberculum majus fractures (p = 0.031). Subgroup analysis showed higher humeral head displacement ratios in Groups 1 and 2 compared to Group 3 (p = 0.010 and p = 0.06, respectively). Tuberculum majus fractures were more frequent in Group 1 compared to Group 3 (p = 0.013), with no significant difference between Groups 2 and 3. Conclusions: In patients experiencing first-time traumatic anterior shoulder dislocations, a greater medial displacement of the humeral head relative to the glenoid rim significantly increases the risk of iatrogenic humeral fractures and the likelihood of unsuccessful closed reduction attempts. Full article

Background: Glenohumeral lateral distraction mobilisation (GLDM) is used in patients with shoulder mobility dysfunction. No one has examined the effect of scapular fixation during GLDM. The aim was to measure and compare the lateral movement of the humeral head and the rotational movement of the scapula when three different magnitudes of forces were applied during GLDM, with and without scapular fixation. Methods: Seventeen volunteers were recruited (n = 25 shoulders). Three magnitudes of GLDM force (low, medium, and high) were applied under fixation and non-fixation scapular conditions in the open-packed position. Lateral movement of the humeral head was assessed with ultrasound, and a universal goniometer assessed scapular rotation. Results: The most significant increase in the distance between the coracoid and the humeral head occurred in the scapular fixation condition at all three high-force magnitudes (3.72 mm; p < 0.001). More significant scapular rotation was observed in the non-scapular fixation condition (12.71°). A difference in scapula rotation (10.1°) was observed between scapular fixation and non-scapular fixation during high-force application. Conclusions: Scapular fixation resulted in more significant lateral movement of the humeral head than in the non-scapular fixation condition during three intensities of GLDM forces. The scapular position did not change during GLDM with the scapular fixation condition. Full article

Accurate measurement of the minimum distance between bony structures of the humeral head and the acromion or coracoid helps advance a better understanding of the shoulder anatomical features. Our goal was to precisely determine the minimum acromiohumeral distance (AHD), coracohumeral distance (CHD), and glenohumeral distance (GHD) in a sample of the Chinese population as an in vivo anatomical analysis. We retrospectively included 146 patients who underwent supine computed tomography (CT) examination of the shoulder joint. The minimum AHD, CHD, and GHD values were quantitatively measured using three-dimensional (3D) CT reconstruction techniques. The correlation between minimum AHD, CHD, and GHD value and age with different sexes was evaluated using Pearson Correlation Coefficient. The mean value of minimum AHD in males was greater than that in females (male 7.62 ± 0.98 mm versus female 7.27 ± 0.86 mm, p = 0.046). The CHD among different sexes differed significantly (male 10.75 ± 2.40 mm versus female 8.76 ± 1.38 mm, p < 0.001). However, we found no statistical differences in GHD with different sexes (male 2.00 ± 0.31 mm versus female 1.96 ± 0.36 mm, p > 0.05). In terms of age correlation, a negative curve correlation existed between age and AHD among the different sexes (male R² = 0.124, p = 0.030, female R² = 0.112, p = 0.005). A negative linear correlation was found in CHD among the different sexes (male R² = 0.164, p < 0.001, female R² = 0.122, p = 0.005). There were no differences between age and minimum GHD in both sexes. The 3D CT reconstruction model can accurately measure the minimum AHD, CHD, and GHD value in vivo and is worthy of further investigation for standard clinical anatomical assessment. Aging may correlate with AHD and CHD narrowing for both sexes. Full article

With the aging society, musculoskeletal degenerative diseases are becoming a burden on society, and rotator cuff disease is one of these degenerative diseases. The purpose of this study was to examine the incidence of shoulder osteoarthritis and the etiologic factors of rotator cuff disease in the Korean elderly population. A total of 102 patients performing ultrasonography were recruited, and their demographic factors were analyzed. As functional factors, visual analog scale and the peak torque of external and internal rotators of the shoulder using an isokinetic dynamometer were measured. As an anatomical factor, the acromiohumeral distance in the plain radiograph of the glenohumeral anterior-posterior view was used. There were more female patients (65.7%) than male patients (34.3%). The age range with the highest number of respondents was 50–59 years old. The mean visual analogue score was 4.09 (Min 1 to Max 9). Age and dominant hand side factors appear to be the crucial etiologic factors of the presence and severity of rotator cuff disease. The lower net value of the external rotator strength is weakly related to the presence of rotator cuff disease after adjusting for age, and this is the only modifiable factor in the study. Full article

Deadspace is the tissue and bony defect in a surgical wound after closure. This space is presumably poorly perfused favouring bacterial proliferation and biofilm formation. In arthroplasty surgery, an obligate deadspace surrounding the prosthesis is introduced and deadspace management, in combination with obtaining therapeutic prophylactic antibiotic concentrations, is important for limiting the risk of acquiring a periprosthetic joint infection (PJI). This study aimed to investigate cefuroxime distribution to an orthopaedic surgical deadspace in comparison with plasma and bone concentrations during two dosing intervals (8 h × 2). In a setup imitating shoulder arthroplasty surgery, but without insertion of a prosthesis, microdialysis catheters were placed for cefuroxime sampling in a deadspace in the glenohumeral joint and in cancellous bone of the scapular neck in eighteen pigs. Blood samples were collected as a reference. Cefuroxime was administered according to weight (20 mg/kg). The primary endpoint was time above the cefuroxime minimal inhibitory concentration of the free fraction of cefuroxime for Staphylococcus aureus (fT > MIC (4 μg/mL)). During the two dosing intervals, mean fT > MIC (4 μg/mL) was significantly longer in deadspace (605 min) compared with plasma (284 min) and bone (334 min). For deadspace, the mean time to reach 4 μg/mL was prolonged from the first dosing interval (8 min) to the second dosing interval (21 min), while the peak drug concentration was lower and half-life was longer in the second dosing interval. In conclusion, weight-adjusted cefuroxime fT > MIC (4 μg/mL) and elimination from the deadspace was longer in comparison to plasma and bone. Our results suggest a deadspace consolidation and a longer diffusions distance, resulting in a low cefuroxime turn-over. Based on theoretical targets, cefuroxime appears to be an appropriate prophylactic drug for the prevention of PJI. Full article

Golf swing analysis is common in both recreational and professional levels where players are searching for improvements in shot accuracy and distance. The use of motion analysis systems such as the portable Polhemus Liberty system is gaining interest by coaches and players; however, to date, no research has examined the usefulness of the Polhemus Liberty system for golf swing analysis. Therefore, the purpose of this study was to determine the reliability of the Polhemus Liberty system and validity compared to the VICON Nexus motion analysis system when assessing segment (pelvis and thorax) and joint (shoulder, elbow and wrist) angular kinematics during a golf swing at key events (address, top of backswing and impact). Fifteen elite amateur/professional golfers performed ten golf swing trials within specified bounds using their 5-iron club. Reliability was assessed using interclass coefficient, effect size and t-test statistics by all participants completing two separate testing sessions on separate days following the same experimental protocol. Validity was assessed using effect size, Pearson correlation and t-test statistics by comparing swings captured using both Polhemus Liberty and VICON Nexus concurrently. Results demonstrated no difference in ball outcome results using the Trackman launch monitor (P > 0.05) and that the Polhemus Liberty system was reliable across the two sessions for all segment (pelvis and thorax) and joint (lead shoulder (gleno-humeral joint), elbow and wrist) angular kinematics (P > 0.05). Validity analysis showed that the Polhemus Liberty system for the segments (pelvis and thorax) and joints (lead shoulder and wrist) were different compared to the VICON Nexus data at key events during the golf swing. Although validity could not be confirmed against VICON Nexus modeling, the Polhemus Liberty system may still be useful for golf swing analysis across training sessions. However, caution should be applied when comparing data from the system to published research data using different motion analysis methods. Full article

Background and Objectives: Sleeper stretching (SS) can improve the shoulder’s range of motion (ROM) for pitchers with glenohumeral internal rotation deficit (GIRD). However, no evidence has proven the effect of Kinesio taping (KT) on shoulder strength and ROM. Therefore, this study compared the effects of SS and KT on shoulder rotation ROM, muscle strength, and sub-acromial distance in pitchers with GIRD. Materials and Methods: Thirty-one pitchers with GIRD were allocated into control, KT, and SS groups. Shoulder rotation ROM, muscle strength, and sub-acromial space were measured before and after treatment with SS or KT. Results: The results revealed that KT and SS significantly enhanced shoulder rotation ROM in pitchers with GIRD. External rotator strength significantly increased following KT but significantly decreased after SS. KT and SS exerted no effects on the sub-acromial space. Conclusions: KT and SS improve shoulder rotation ROM in pitchers with GIRD. In addition, KT improves shoulder external rotator strength, and SS reduces it. Full article

Background: Kinematic changes of the scapulothoracic joint may influence the relative position of the glenoid fossa and, consequently, the glenohumeral joint. As the alignment of the scapula relative to the thorax differs between individuals, such variability may be another factor in the development of posterior head subluxation. The purpose of this study was to compare scapulothoracic alignment in pathologic type B shoulders with contralateral healthy shoulders. Methods: Seven adult volunteers with unilateral type B glenohumeral osteoarthritis (OA) underwent bilateral computed tomography (CT) scans of the shoulders and arms. A patient-specific, three-dimensional measurement technique that coupled medical imaging (i.e., CT) and optical motion capture was used. Results: The scapulothoracic distance at the trigonum was 75 ± 15 mm for pathologic shoulders and 78 ± 11 mm for healthy shoulders (p = 0.583), while at the inferior angle, it was 102 ± 18 mm for pathologic shoulders and 108 ± 12 mm for healthy shoulders (p = 0.466). Conclusion: Scapula positioning at a resting position did not differ between pathologic and healthy shoulders. However, pathologic shoulders tended to be limited in maximal glenohumeral motion and exhibited greater anterior tilt of the scapula in internal rotation at 90 degrees, which may be adaptive to the restricted glenohumeral motion. Full article