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BACKGROUND: Although it is considered a sensitive indicator of shoulder disabilities, the scapulohumeral rhythm has not been investigated after anterior glenohumeral stabilization with open Latarjet procedure. This study aimed to assess the short-term influence of glenohumeral stabilization on scapulohumeral rhythm in patients who underwent open Latarjet procedure compared to asymptomatic individuals. METHODS: A group of male patients who underwent anterior glenohumeral stabilization by open Latarjet procedure and a healthy group were enrolled in this study. An electromagnetic device was used to record scapulothoracic and glenohumeral joint kinematics during dynamic arm elevation and depression in the scapular plane before and three months after surgery. Then, the three-dimensional dynamic scapulohumeral rhythm was computed bilaterally. SPM ANOVAs were used for statistical analysis. FINDINGS: Twenty-two participants per group were included. The scapulohumeral rhythm of the two groups increased from 1.88 [mean] ± 0.79 [standard deviation] to 2.83 ± 1.52 during the ascending phase, while a decrease followed by a slight increase in the scapulohumeral rhythm were observed during the descending phase. The scapulohumeral rhythm did not significantly differ between the operated and non-operated sides or before and after surgery. When pooling the sides for each group, no significant differences were observed between the groups. INTERPRETATION: The scapulohumeral rhythm in patients who underwent the Latarjet procedure is not modified three months after surgery and is similar to the scapulohumeral rhythm of asymptomatic individuals. These findings suggest that in addition to restoring glenohumeral stability, the open Latarjet procedure preserves shoulder joint coordination three months postoperatively.

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INTRODUCTION: Pathologies of the scapulothoracic articulation may lead to painful symptoms such as crepitus and bursitis. While conservative treatments are preferred, persistent symptoms may require image-guided injections. This study aims to determine the optimal hand positioning during ultrasound to maximize the distance between the scapula and thoracic wall, and improve its accessibility during injections. METHODS: This cross-sectional observational study included ten healthy adult volunteers without scapulothoracic issues or history of trauma/surgery. Two musculoskeletal radiologists independently measured the scapulothoracic distance on Ultrasound in three hand positions: 1. Hands under the head; 2. Hands by the side of the trunk; and 3. Hands hanging by the side of the couch. Data was analyzed using SPSS 24.0. Continuous variables were described using mean and standard deviation (SD), with significance set at p < 0.05. RESULTS: Measurements on 20 scapulothoracic articulations (10 volunteers) showed the following findings: Position 1: Baseline value of 1. Position 2: Distance increased by 1.515 mm ± 3.617 (95% CI [- 0.0178, 3.208]. Position 3: Distance increased by 2.175 mm ± 0.66 (95% CI [0.793, 3.557]. Statistical analysis indicated no significant difference (p = 0.39) between positions. However, both radiologists subjectively noted that positions 2 and 3 provided better access for interventions. CONCLUSION: This study highlights the importance of hand positioning in optimizing the scapulothoracic distance for therapeutic interventions. While no significant statistical differences were found, the results suggest potential benefits for clinical practice. Further research with larger samples is needed to establish evidence-based guidelines for scapulothoracic injections.

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BACKGROUND: The debate surrounding the influence of the open Latarjet procedure on postoperative scapular motions persists, and there is no evidence regarding its effects on periscapular muscle activation. This study aimed to assess the short-term influence of the open Latarjet procedure on scapular kinematics and periscapular muscle activity during arm raising and lowering based on comparisons between patients and healthy athletes. METHODS: 22 healthy male athletes and 22 male athletes scheduled for glenohumeral stabilization surgery by the open Latarjet procedure were included. Scapular kinematics, periscapular muscle activities, and shoulder-related quality of life were recorded before surgery and 3 months postoperatively for the Latarjet group. For the healthy group, same assessments were performed 3 months apart. Bilateral differences in both scapular kinematics and periscapular muscle activation ratios and the Western Ontario Shoulder Instability (WOSI) index were defined as dependent variables. RESULTS: Scapular kinematics of the operated shoulder, namely scapular upward/downward rotation, internal/external rotation, and anterior/posterior tilt recorded between 20° and 120° of humerothoracic elevation, showed no alterations 3 months after surgery (P > .05) and did not differ from those observed in healthy athletes (P > .05). Similarly, all periscapular muscle activations were not different within time and between groups (P > .05). The WOSI index of the operated shoulder was significantly improved postoperatively (871.9 ± 443.7 vs. 1346.3 ± 552.3) but remained higher than the WOSI indices of the nonoperated shoulder or those of the healthy group (52.7 ± 75.6). CONCLUSIONS: This study emphasizes the short-term effects of the open Latarjet procedure, demonstrating an improvement in the shoulder-related quality of life 3 months after surgery. Notably, during this period, both kinematics and periscapular muscle activity remained consistent and similar to the patterns observed for healthy athletes.

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INTRODUCTION: The purpose of this study was to analyze the real range of motion (RoM) measured in patients operated on for reverse shoulder arthroplasty (RSA) and compare it to the virtual RoM provided by the preoperative planning software. HYPOTHESIS: There was a difference between virtual and real RoM, which can be explained by different factors, specifically the scapula-thoracic (ST) joint. METHODS: Twenty patients with RSA were assessed at a minimum follow-up of 18 months. Passive RoM in forward elevation abduction, without and with manually locking the ST joint, and in external rotation with arm at side were recorded. The humerus, scapula, and implants were manually segmented on post-operative CTs. Post-operative bony structures were registered to preoperative bony elements. From this registration, a post-operative plan corresponding to the real post-operative implant positioning was generated and the corresponding virtual RoM analysis was recorded. On the post-operative anteroposterior X-rays and 2D-CT coronal planning view, the glenoid horizontal line angle (GH), the metaphyseal horizontal line angle (MH), and the gleno-metaphyseal angle (GMA) were measured to assess the extrinsic glenoid inclination, as well as the relative position of the humeral and glenoid components. RESULTS: There were some significant differences between virtual and post-operative passive abduction and forward elevation, with (55° and 50°, p < 0.0001) or without ST joint participation (15° and 27°, p < 0.002). For external rotation with arm at side, there was no significant difference between planning (24° ± 26°) and post-operative clinical observation (19° ± 12°) (p = 0.38). For the angle measurements, the GMA was significantly higher (42.8° ± 15.2° vs. 29.1°± 18.2°, p < 0.0001), and the GH angle, significantly lower on the virtual planning (85.2° ± 8.8° vs. 99.5° ± 12.5°, p < 0.0001), while the MH was not different (p = 0.33). CONCLUSIONS: The virtual RoM given by the planning software used in this study differs from the real post-operative passive RoM, except for external rotation. This can be explained by the lack of ST joint and soft tissues simulation. However, in focusing on the virtual GH participation, the simulation looks informative. Some modifications between the glenoid and humerus starting positions before running the motion analysis could be provided for making it more realistic and predictive of the RSA functional results. LEVEL OF EVIDENCE: III.

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Background: Existing kinematic studies of the shoulder girdle focus on humerothoracic movements. Isolated scapulothoracic movements are also performed during daily activities and rehabilitation but kinematic values are lacking. Methods: A kinematic analysis was performed in 14 cadaveric shoulders during protraction, retraction, and shrug. An optical navigation system was used to analyze sternoclavicular, scapulothoracic, and acromioclavicular motions. Results: In the sternoclavicular joint, shrug and retraction caused a posterior clavicular rotation of 5° (standard deviation [SD] 6°) and 3° (SD 2°), while protraction induced an anterior rotation of 3° (SD 2°). Shrug caused a large clavicular elevation of 25° (SD 5°). Shrug and retraction caused an increase in retraction of 17° (SD 5°) and 9° (SD 2°). Protraction induced an increase of 10° (SD 2°) toward protraction. In the scapulothoracic joint, shrug induced an increase of 3° (SD 2°) in anterior scapular tilt, and a lateral rotation of 26° (SD 4°). Retraction caused a lateral rotation of 4° (SD 3°). Protraction caused an increase of 7° (SD 2°) in the scapular protraction position, while shrug and retraction demonstrated a decrease of 9° (SD 2°) and 6° (SD 5°). In the acromioclavicular joint, posterior tilting of the scapula compared to the clavicle increased 23° (SD 6°) during shrug, while during protraction an increase of only 4° (SD 3°) was seen. During shrug, relative lateral rotation increased 13° (SD 4°). The protraction movement decreased the relative protraction position with 3° (SD 2°). Conclusion: This study provided normative kinematic values of scapulothoracic movements in the shoulder girdle.

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BACKGROUND: Shoulder external rotation in the throwing motion involves movement of the scapulothoracic and glenohumeral joints, thoracic spine, and the thorax. Restriction of thoracic expansion may decrease scapulothoracic joint motion and compensate by excessive glenohumeral joint motion. However, it is unclear how restricting the expansion of the thorax alters shoulder motion. OBJECTIVE: To elucidate changes in scapulothoracic and glenohumeral joint movements caused by restricted thoracic expansion. METHODS: Kinematic data were obtained using an electromagnetic tracking device (Liberty; Polhemus), from 18 male participants, during shoulder external rotation in the sitting position with and without restriction of thoracic expansion. The displacements from the start position to the maximum external rotation position were compared, and Pearson's correlation coefficient was calculated. RESULTS: A significant difference was observed in the scapulothoracic posterior tilt angle (P< 0.01) and glenohumeral external rotation angle (P< 0.01). A significant positive correlation existed between scapulothoracic posterior tilt and glenohumeral external rotation (P< 0.05) with and without restriction. CONCLUSIONS: Restriction of thoracic expansion decreased scapulothoracic motion and increased glenohumeral motion. Thus, a decrease in thoracic expansion may change scapulothoracic and glenohumeral movements, which may be a risk factor for throwing injuries.

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BACKGROUND: Though alignment of the spine and lower extremities in the standing neutral position has been evaluated, a few studies evaluating the alignment of the upper extremities have also been made. This study assessed the normal alignment of the upper extremities in the standing neutral position and clarified the three-dimensional angular rotations of the upper extremity joints. METHODS: Computed tomography (CT) images of 158 upper extremities from 79 healthy volunteers were prospectively acquired in the standing neutral position using an upright CT scanner. Three-dimensional coordinate systems of the thorax, scapula, humerus, and forearm were designated, and three-dimensional angular rotations of the scapulothoracic, glenohumeral, and elbow joints were calculated. RESULTS: The median angle of the scapulothoracic joint was 9.2° (interquartile range [IQR], 5.2°-12.5°) of upward rotation, 29.0° (IQR, 24.9°-33.3°) of internal rotation, and 7.9° (IQR, 4.3°-11.8°) of anterior tilt. The median angle of the glenohumeral joint was 4.5° (IQR, 0.9°-7.8°) of abduction, 9.0° (IQR, 2.2°-19.0°) of internal rotation, and 0.3° (IQR, - 2.6°-3.1°) of extension. The median angle of the elbow joint was 9.8° (IQR, 6.9°-12.4°) of valgus, 90.2° (IQR, 79.6°-99.4°) of pronation, and 15.5° (IQR, 13.2°-18.1°) of flexion. Correlations in angular rotation values were found between the right and left upper extremities and between joints. CONCLUSIONS: This study clarified the three-dimensional angular rotation of upper extremity joints in the standing neutral position using an upright CT scanner. Our results may provide important insights for the functional evaluation of upper extremity alignment.

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BACKGROUND: In Sprengel's deformity, loss of shoulder motion has been attributed exclusively to scapulothoracic stiffness. The purposes of this study were to evaluate passive glenohumeral (GH) joint motion in these children. METHODS: A prospective evaluation of 23 children was performed. Obtained data were demographics, Cavendish grade, bilateral active global shoulder elevation, and multidirectional passive GH range of motion, including: (a) GH internal rotation in abduction and GH cross-body adduction to assess for posterior GH contracture; (b) spinohumeral abduction angle (SHABD) to assess for inferior GH contracture; (c) spinohumeral adduction angle to assess for superior GH contracture; and (d) passive external rotation in shoulder adduction and abduction to assess for anterior GH contracture. Paired t tests and both Pearson's and Spearman's correlation analyses were performed. RESULTS: The mean patient age was 8.1 years (range, 1.4-16.7 years), with 13.4% of deformities Cavendish grade 1, 52.2% grade 2, 13.4% grade 3, and 21.7% grade 4. The involved shoulder showed a statistically significant decrease in mean active global shoulder elevation (117.4° vs. 176.1°), SHABD (14.6° vs. 41.5°), cross-body adduction (43° vs. 71.3°), and internal rotation in abduction (17.8° vs. 49.4°), all at P < .001. Strong inverse correlations were noted between Cavendish grade and both global shoulder elevation (r, -0.784) and SHABD (r, -0.669). Cavendish grade IV patients showed a mean decrease of 45° (range, 40°-60°) of SHABD. CONCLUSION: Shoulder elevation is also impaired by GH joint contractures.

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BACKGROUND: Although humans spend most of their day in a standing or sitting position, it is difficult to accurately evaluate the alignment of the shoulder girdle during daily activity, and its alignment changes between positions. The purpose of this study was to evaluate the 3-dimensional alignment of the shoulder girdle in the supine and standing positions by computed tomography (CT) and to assess the alignment changes of the shoulder girdle between these two positions. METHODS: CT scans of both shoulders of 100 healthy volunteers were prospectively taken in both supine and standing positions on the same day. The local 3-dimensional coordinate systems of the thorax, clavicle, and scapula were defined from the specific bony landmarks, and 3-dimensional angular rotations and positions of the clavicle and scapula were calculated. Differences in rotations and positions of the clavicle and scapula were evaluated between the supine and standing positions. RESULTS: Compared with the supine position, the clavicle showed significantly less elevation and greater retraction, and the scapula showed significantly less upward rotation, anterior tilting, and internal rotation in the standing position. Compared with the supine position, the clavicle center was located more inferiorly, posteriorly, and laterally, and the scapula center was located more inferiorly, posteriorly, and medially in the standing position. CONCLUSIONS: The present study showed that angular rotations and positions of the clavicle and scapula change significantly with position due to the effect of gravity.

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BACKGROUND: The trapezius is an extensive muscle subdivided into upper, middle, and lower parts. This muscle is a dominant stabilizer of the scapula, normally operating synergistically with other scapular muscles, most notably the serratus anterior. Altered activation, poor control, or reduced strength of the different parts of the trapezius have been linked with abnormal scapular movements, often associated with pain. Several exercises have been designed and studied that specifically target the different parts of the trapezius, with the goal of developing exercises that optimize scapular position and scapulohumeral rhythm that reduce pain and increase function. METHODS: This paper describes the anatomy, kinesiology, and pathokinesiology of the trapezius as well as exercises that selectively target the activation of the different parts of this complex muscle. CONCLUSIONS: This review provides the anatomy and kinesiology of the trapezius muscle with the underlying intention of understanding how this muscle contributes to the normal mechanics of the scapula as well as the entire shoulder region. This paper can guide the clinician with planning exercises that specifically target the different parts of the trapezius. It is recommended that this paper be read as a companion to another paper: Kinesiologic considerations for targeting activation of scapulothoracic muscles - part 1: serratus anterior.

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BACKGROUND: The serratus anterior (SA) is capable of a wide range of actions across the scapulothoracic joint. Furthermore, the lack of control, strength, or activation of this important muscle is believed to be associated with several painful conditions involving the shoulder complex. Studies and clinical intuition have therefore identified several exercises that selectively target the activation of the SA. METHODS: This paper reviews the anatomy, innervation, testing, and complex actions of the SA. In addition, this paper describes the classic signs and symptoms of weakness or reduced activation of the SA. Several exercises are described and illustrated that purportedly target the activation of the SA, with the intention of optimizing muscular control and encouraging pain free shoulder motion. CONCLUSIONS: This review provides the theoretical background and literature-based evidence that can help explain the SA's complex pathokinesiology, as well as guide the clinician to further develop exercises that likely challenge the muscle. This paper is written along with a companion paper entitled: Kinesiologic considerations for targeting activation of scapulothoracic muscles: part 2: trapezius. Both papers prepare the reader to expand their pallet of exercises that target and challenge these two dominant muscles, with a goal of improving function of the shoulder for several painful conditions caused by their reduced or altered activation pattern.

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CONTEXT: Several studies have shown that the kinematics of the scapula is altered in many disorders that affect the shoulder. Description of scapular motion in the chest continues to be a scientific and clinical challenge. OBJECTIVE: To check the validity and reliability of a new, minimally invasive method of tracking the internal and external rotation of the scapula using ultrasound imaging combined with the signal provided by a 3-dimensional electromagnetic sensor. DESIGN: A cross-sectional study with a repeated-measures descriptive test-retest design was employed to evaluate this new tracking method. The new method was validated in vitro and the reliability of data over repeated measures between scapula positions was calculated in vivo. SETTING: University laboratory. PARTICIPANTS: A total of 30 healthy men and women. MAIN OUTCOME MEASURE: The validation of the scapula rotation tracking using the in vitro model was calculated by Pearson correlation test between a 2-dimensional cross-correlation algorithm of the new method and another software image. The reliability of the tracking of the scapula rotation was measured using the intraclass correlation coefficient. RESULTS: In the validation in vitro, the correlation of rotations obtained by the 2 methods was good (r = .77, P = .01). The reliability in vivo had excellent results (intraclass correlation coefficient = .88; 95% confidence interval, .82-.93) in the test-retest analysis of 8 measures. The intrarater analysis of variance test showed no significant differences between the measures (P = .85, F = 0.46). CONCLUSION: Ultrasound imaging combined with a motion sensor to track the scapula has been shown to be a reliable and valid method for measuring internal and external rotation during separation of the upper limb.

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INTRODUCTION: Scapulothoracic articulation has several bursae which allow a sliding movement of the scapulothoracic joint. The two major anatomical bursae are the supraserratus bursa and infraserratus bursa. PRESENTATION OF CASE: It was a case of a 59 year-old female patient with a professional load and a clinical finding of bilateral subscapular resistances of the thorax. The finding of bilateral collections in the intermuscular spaces between external intercostal muscles and heads of serratus anterior muscle was verified by magnetic resonance. CONCLUSION: Due to progressively increasing bilateral findings an open surgical resection was implemented, with good result.

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[Purpose] The glenohumeral, scapular, and thoracic angles at maximum shoulder external rotation during shadow pitching were evaluated and compared with those observed during normal pitching. [Participants and Methods] Our study included 13 healthy males with experience in pitcher activity. All participants performed both, shadow pitching using a towel and normal pitching using a ball. The external rotation of the glenohumeral joint, scapular posterior tilting, and thoracic extension angles in the cocking phase were measured using a 3-dimensional motion analysis system. The ratios of the glenohumeral external rotation angle to the scapular posterior tilting and/or thoracic extension angle were calculated to evaluate the contribution of the scapulothoracic joint at maximum external rotation during throwing/pitching activity. [Results] The glenohumeral external rotation angle at maximum shoulder external rotation was significantly smaller during shadow pitching than during normal pitching. The ratio of the glenohumeral external rotation angle to the scapular posterior tilting and/or thoracic extension angle showed no statistically significant difference. [Conclusion] We conclude that shadow pitching can reduce the external rotation motion of the glenohumeral joint compared to that during normal pitching and might be a useful pre-throwing program beneficial in the rehabilitation of those presenting with throwing injuries.

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OBJECTIVES: The purpose of this study was to investigate the effects of additional 6-week scapular stabilization training in patients with nonspecific neck pain (NNP). MATERIALS AND METHODS: A total of 30 patients with NNP were randomly allocated to the study. Fifteen participants in the intervention group received neck-focused exercise and scapular stabilization training, whereas 15 participants in the control group received neck-focused exercise training. All groups were evaluated at baseline and after 6 weeks of rehabilitation. The pain intensity on the neck was measured with the visual analog scale (VAS). The self-reported disability status was measured with the neck disability index (NDI). Three-dimensional scapular kinematics were recorded during dynamic shoulder elevation trials using an electromagnetic tracking device, and data were further analyzed at 30°, 60°, 90°, and 120° of humerothoracic elevations. RESULTS: Comparisons revealed that, regardless of the received treatment, after 6 weeks of training both groups showed significant improvements in VAS (P < .001) and NDI (P < .001) scores. Both VAS and NDI outcomes have a large effect size (r = .618 and r = .619, respectively). For scapular kinematics, there were no group differences, especially for scapular upward-downward rotation and anterior-posterior tilt (P > .05). However, in the intervention group, the scapula was more externally rotated at 120° humerothoracic elevation (P = .04). CONCLUSION: Findings of this study showed that both manual therapy and active interventions, including neck-focused exercise and scapular stabilization training, are effective in decreasing pain and disability level in patients with NNP. More comprehensive studies with longer follow-up durations are needed to better understand the potential effects of scapular stabilization training in patients with NNP.

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BACKGROUND: The physical signs of obstetrical brachial plexus palsy range from temporary upper-limb dysfunction to a lifelong impairment and deformity in one arm. The aim of this study was to analyze the kinematics of the upper limb and to evaluate the contribution of glenohumeral and scapulothoracic joints of obstetrical brachial plexus palsy children. METHODS: Six children participated in this study: 2 males and 4 females with a mean age of 11.7years. Three patients had a C5, C6 lesion and 3 had a C5, C6, C7 lesion. They were asked to perform five tasks based on the Mallet scale and the kinematic data were collected using the Fastrak electromagnetic tracking device. FINDINGS: The scapulothoracic protraction and posterior tilt were significantly increased in the involved limb during the hand to mouth task (p=0.006 and p=0.015 respectively). The scapulothoracic Protraction/glenohumeral Elevation ratio was significantly increased in the involved limb during the hand to neck task (p=0.041) and the elevation task (p=0.015). The ratios of scapulothoracic Tilt on the three glenohumeral excursion angles were significantly increased during the hand to mouth task (p≤0.041). The scapulothoracic Mediolateral/glenohumeral Elevation ratio was significantly increased in the involved limb during the elevation task (p=0.038). The glenohumeral elevation excursion was significantly decreased in the involved limb during the hand to neck task (p<0.001) and the elevation task (p=0.0003). INTERPRETATION: This study gives us information about the greater contribution of the scapulothoracic joint to shoulder motion for affected arm of obstetrical brachial plexus palsy patients compared to their unaffected arm. Kinematic analysis could be useful in shoulder motion evaluation during the Mallet score and to evaluate outcomes after surgery.

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Objetivo: Descrever cinco casos de elastofibroma dorsi (quatro unilateral e um bilateral) em pacientes que foram tratados previamente como tendinopatia do ombro. Materiais e métodos: Os pacientes referiam dor na região do trapézio, além de história, testes clínicos e exames de imagem positivos para tendinopatia do manguito rotador. Foram tratados previamente de forma não cirúrgica, por meio de medicamentos e fisioterapia, sendo encaminhados para tratamento artroscópico (descompressão subacromial e reparo do manguito rotador). Ao procurarem nosso serviço, em todos os casos se notou ao exame físico: discinesia escapulotorácica, ressalto e crepitação. Resultados: Optou-se pelo tratamento cirúrgico de forma aberta (ressecção tumoral), após diagnóstico por imagem compatível com elastofibroma dorsi. Realizou-se a ressecção da tumoração em três pacientes, pois dois recusaram o tratamento cirúrgico. Nos casos operados, o exame anatomopatológico confirmou o diagnóstico. Todos os pacientes operados obtiveram melhora do quadro de síndrome do impacto non-outlet. Conclusão: Os autores destacam que, embora rara, essa afecção deva ser considerada como diagnóstico diferencial da síndrome do impacto subacromial e salientam a importância do exame físico, em especial da articulação escapulotorácica para o correto diagnóstico desta lesão pseudotumoral.

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CONTEXT: During gymnastic exercises, considerable force output is required in the shoulder girdle muscles. Isokinetic performance of the scapular muscles in young, elite gymnasts has not been examined. OBJECTIVE: To compare the isokinetic muscle performance of the scapular muscles between elite adolescent gymnasts and nonathletic adolescents to identify differences in strength, endurance, and muscle balance based on high-level sport participation. DESIGN: Single-session, repeated-measures design. SETTING: University human research laboratory. PATIENTS OR OTHER PARTICIPANTS: Sixteen young, elite gymnasts and 26 age-matched nonathletic subjects participated in the study. INTERVENTION(S): Linear protraction-retraction movement in the scapular plane at 2 velocities (12.2 cm/s and 36.6 cm/s). MAIN OUTCOME MEASURE(S): Isokinetic strength and endurance values, peak force/body mass, work/body mass, fatigue index (difference between the work performed in the first third and the last third of the test), and protraction to retraction strength ratios. RESULTS: Elite gymnasts demonstrated higher values for the protraction peak force/body mass than the control group demonstrated (P < .05), and they demonstrated higher protraction to retraction ratios on the nondominant side than on the dominant side (P < .05 at low velocity, P < .001 at high velocity). Work/body mass and fatigue index values were not statistically different between the groups. Side differences (P = .003) for retraction strength with lower protraction to retraction ratios (P < .001) were apparent in the gymnast group on the dominant side. CONCLUSIONS: Scapular muscle performance in elite, young gymnasts is characterized by increased protraction strength and altered muscular balance around the scapula compared with nonathletic adolescents.

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PURPOSE: We expected the motion fraction could be checked, with simple radiographic examination, according to the guide-line of fluoroscopic technique, and recovery of the function also could be correlated with the improvement of the motion fraction. MATERIALS AND METHODS: We measured the motion fraction of the glenohumeral and scapulothoracic movement using fluoroscope in 30-degree intervals of arm elevation in the scapular plane. The ratio of glenohumeral to scapulothoracic movement (thetaGH/thetaST) was 1.6 for the full range of motion in scapular plane. During arm elevation, scapular tilting from the coronal plane was decreased from 42 degrees to 20 degrees tilting as well as internal rotation (scapular extension). We also measured the motion fraction (thetaGH/thetaST) and functional recovery of the shoulder in 11 patients after operative treatment of the shoulder instability in 15 patients from December 1996 to August 1997. RESULTS: We could find out a significant correlation between the recovery of motion fraction and shoulder function. These results would be applied in planing rehabilitation program after treatment of the shoulder instability. CONCLUSIONS: The measuring technique of glenohumeral to scapulothoracic movement (thetaGH/thetaST) with fluoroscopy could be applied to the simple radiographic measurement at the out-patient clinic in order to identify the pathology and recovery of shoulder motion after treatment

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