RESUMO
BACKGROUND: Recent evidence suggests that internal impingement, or rotator cuff tendon deformation against the glenoid, occurs during overhead motions and may therefore be a mechanism of pathology even in non-athletes. Clinically, knowing how movement impacts potential injury mechanisms would be useful to guide movement-based treatment strategies. OBJECTIVE: To compare the distance between the glenoid and rotator cuff footprint between two groups classified based on scapulothoracic upward rotation (UR) magnitude (i.e., low, high) at 90° humerothoracic elevation. METHODS: Shoulder kinematics were quantified during scapular plane abduction in 60 participants using single-plane fluoroscopy. Of these, 40 were subsequently classified as having high or low scapulothoracic UR based on the sample's distribution. The minimum distance between the glenoid and rotator cuff footprint was calculated along with the locations of closest proximity (i.e., proximity centers). Minimum distances and proximity center locations were compared between groups using 2-factor mixed-model ANOVAs. The prevalence of glenoid-to-footprint contact was also compared. RESULTS: Glenoid-to-footprint distances consistently decreased as humerothoracic elevation angle increased, and the anterior aspect of the footprint was closest to the posterosuperior glenoid. Minimum distances were not significantly different between UR groups (p≥0.16). However, group differences existed in proximity center locations (p<0.01). Glenoid-to-footprint contact was identified in 75.0% of participants at an average (SD) of 133.6° (3.2°) humerothoracic elevation. CONCLUSION: The results of this study suggest that decreased UR as classified and assessed in this study does not significantly impact glenoid-to-footprint distances but does alter the location of the contact, which occurred in most participants.
Assuntos
Síndrome de Colisão do Ombro , Articulação do Ombro , Humanos , Manguito Rotador , Rotação , Escápula , Fenômenos BiomecânicosRESUMO
BACKGROUND: Physical therapists use several evaluation measures to identify the most important factors related to disability. However, the degree to which these evaluation components explain shoulder disability is not well known and that may detract clinicians from the best clinical reasoning. OBJECTIVE: To determine how much evaluation components explain shoulder function. METHODS: Eighty-one individuals with unilateral shoulder pain for at least four weeks and meeting clinical exam criteria to exclude cervical referred pain, adhesive capsulitis, and shoulder instability, participated in this study. Several typical clinical evaluation components were assessed as potential independent variables in a regression model using the Disabilities of the Arm, Shoulder, and Hand (DASH) score as a proxy to shoulder function. Two multivariate models were built to include (1) evaluation components from physical exam plus clinical history and (2) a model considering all previous variables and magnetic resonance imaging (MRI) data. RESULTS: Pain catastrophizing was the best variable in the model explaining at least 10% of the DASH variance. Sex and lower trapezius muscle strength explained considerably less of shoulder function. The MRI data did not improve the model performance. CONCLUSION: The complexity of shoulder function is not independently explained by pathoanatomical abnormalities. Psychological aspects may explain more of shoulder function even when combined with physical components in some patients.
Assuntos
Instabilidade Articular , Articulação do Ombro , Estudos Transversais , Avaliação da Deficiência , Humanos , Ombro , Dor de OmbroRESUMO
BACKGROUND: Clinical laxity tests are commonly used together to identify individuals with multidirectional instability (MDI). However, their biomechanical validity in distinguishing distinct biomechanical characteristics consistent with MDI has not been demonstrated. OBJECTIVE: To determine if differences in glenohumeral (GH) joint laxity exist between individuals diagnosed with multidirectional instability (MDI) and asymptomatic matched controls without MDI. METHODS: Eighteen participants (9 swimmers with MDI, 9 non-swimming asymptomatic matched controls without MDI) participated in this observational study. Participants were classified as having MDI with a composite laxity score from three laxity tests (anterior/posterior drawer and sulcus tests). Single plane dynamic fluoroscopy captured joint motion with 2D-3D joint registration to derive 3D joint kinematics. Average GH translations occurring during the laxity tests were compared between groups using an independent sample's t-test. The relationship of composite laxity scores to overall translations was examined with a simple linear regression. Differences of each laxity test translation between groups were analyzed with a two-way repeated measures ANOVA. RESULTS: Mean composite translations for swimmers were 1.7 mm greater (p = 0.04, 95% Confidence Interval (CI): 0.1, 3.3 mm) compared to controls. A moderate association occurred (r2 = 0.40, p = 0.005) between composite laxity scores and composite translation. Greater translations for the posterior drawer (-2.4 mm, p = 0.04, 95% CI: -0.1, -4.6) and sulcus tests (-2.7 mm, p = 0.03, 95% CI: -0.3, -5.0) existed in swimmers compared to controls. CONCLUSION: Significant differences in composite translation existed between symptomatic swimmers with MDI and asymptomatic control participants without MDI during GH joint laxity tests. The results provide initial biomechanically based construct validity for the clinical criteria used to identify individuals with MDI.
Assuntos
Instabilidade Articular , Articulação do Ombro , Fenômenos Biomecânicos , Humanos , Instabilidade Articular/diagnóstico , Amplitude de Movimento ArticularRESUMO
BACKGROUND: Alterations in glenohumeral and scapulothoracic kinematics have been theorized to contribute to rotator cuff pathology by impacting the magnitude of the subacromial space. OBJECTIVE: The purpose of this review is to summarize what is currently known about the relationship between shoulder kinematics and subacromial proximities. CONCLUSIONS: A variety of methods have been used to quantify subacromial proximities including photographs, MR imaging, ultrasonography, and single- and bi-plane radiographs. Changes in glenohumeral and scapulothoracic kinematics are associated with changes in subacromial proximities. However, the magnitude and direction of a particular motion's impact on subacromial proximities often vary between studies, which likely reflects different methodologies and subject populations. Glenohumeral elevation angle has been consistently found to impact subacromial proximities. Plane of humeral elevation also impacts subacromial proximities but to a lesser degree than the elevation angle. The impact of decreased scapulothoracic upward rotation on subacromial proximities is not absolute, but instead depends on the angle of humerothoracic elevation. The effects of scapular dyskinesis and humeral and scapular axial rotations on subacromial proximities are less clear. Future research is needed to further investigate the relationship between kinematics and subacromial proximities using more homogenous groups, determine the extent to which compression and other factors contribute to rotator cuff pathology, and develop accurate and reliable clinical measures of shoulder motion.
Assuntos
Discinesias/fisiopatologia , Manguito Rotador/fisiopatologia , Ombro/fisiologia , Ultrassonografia/métodos , Humanos , Escápula/fisiologiaRESUMO
BACKGROUND: Magnetic resonance imaging (MRI) is commonly used to diagnose structural abnormalities in the shoulder. However, subsequent findings may not be the source of symptoms. The aim of this study was to determine comparative MRI findings across both shoulders of individuals with unilateral shoulder symptoms. MATERIALS AND METHODS: We prospectively evaluated 123 individuals from the community who had self-reported unilateral shoulder pain with no signs of adhesive capsulitis, no substantial range-of-motion deficit, no history of upper-limb fractures, no repeated shoulder dislocations, and no neck-related pain. Images in the coronal, sagittal, and axial planes with T1, T2, and proton density sequences were generated and independently and randomly interpreted by 2 examiners: a board-certified, fellowship-trained orthopedic shoulder surgeon and a musculoskeletal radiologist. Absolute and relative frequencies for each MRI finding were calculated and compared between symptomatic and asymptomatic shoulders. Agreement between the shoulder surgeon and the radiologist was also determined. RESULTS: Abnormal MRI findings were highly prevalent in both shoulders. Only the frequencies of full-thickness tears in the supraspinatus tendon and glenohumeral osteoarthritis were higher (approximately 10%) in the symptomatic shoulder according to the surgeon's findings. Agreement between the musculoskeletal radiologist and shoulder surgeon ranged from slight to moderate (0.00-0.51). CONCLUSION: Most abnormal MRI findings were not different in frequency between symptomatic and asymptomatic shoulders. Clinicians should be aware of the common anatomic findings on MRI when considering diagnostic and treatment planning.
Assuntos
Imageamento por Ressonância Magnética , Articulação do Ombro/diagnóstico por imagem , Dor de Ombro/etiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Osteoartrite/diagnóstico por imagem , Estudos Prospectivos , Radiologistas , Lesões do Ombro/diagnóstico por imagem , Cirurgiões , Sinovite/diagnóstico por imagem , Tendinopatia/diagnóstico por imagem , Traumatismos dos Tendões/diagnóstico por imagem , Adulto JovemRESUMO
OBJECTIVE: To assess concurrent validity, between and within-day reliability of scapular and clavicular digital inclinometer measures. DESIGN: Test-retest and concurrent validity. SETTING: Laboratory. PARTICIPANTS: Twenty-three participants with and without shoulder symptoms. MAIN OUTCOME MEASURES: Static positions of scapular upward rotation, anterior/posterior tilting and clavicular elevation were measured between days with an inclinometer and compared to a 3-dimensional electromagnetic tracking system in different positions of sagittal plane humeral elevation (neutral, 30°, 60°, 90°, 120°). The two methods were compared using a two-way Analysis of Variance. Linear regressions at each arm position were also performed to further assess concurrent validity. RESULTS: Between-day reliability demonstrated Intraclass Correlation Coefficients ≥ 0.50 for all comparisons. There were statistically significant differences between methods or interactions of method and arm position for clavicle elevation (p = 0.004, maximum offset between methods 7.7º in the neutral position), and scapular upward rotation (p = 0.001). For scapular upward rotation, the maximum difference between methods was less than 2° across all humeral positions. Clavicle elevation (r = 0.67-0.82) and scapular upward rotation (r = 0.57-0.81) demonstrated higher correlations between measurement methods than scapular anterior/posterior tilt (r = 0.10-0.67). CONCLUSIONS: Concurrent validity in assessing scapular upward rotation and clavicle elevation with an inclinometer was shown when compared with electromagnetic tracking. However, the inclinometer method may not have adequate concurrent validity to clinically measure scapular anterior/posterior tilting.
Assuntos
Clavícula/fisiologia , Modalidades de Fisioterapia/normas , Escápula/fisiologia , Adulto , Feminino , Humanos , Masculino , Modalidades de Fisioterapia/instrumentação , Reprodutibilidade dos TestesRESUMO
This study evaluated the effectiveness of a rehabilitation program performed during working hours on function and pain in workers with subacromial impingement syndrome. Fourteen male workers (31.93 +/- 5.86 years) in the school supply industry were assessed. The duration of their shoulder pain was 28.50 +/- 33.64 months, and their amount of time in this industry was 9.07 +/- 3.68 years. The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire evaluated function of the upper limbs. The Mc Gill Pain Questionnaire quantified the pain by the number of words chosen and the pain rating index (PRI). Subjects completed an 8-week rehabilitation program, twice a week, consisting of cryotherapy, strengthening, and stretching exercises. Subjects' outcome data were collected pre- and post-intervention. The results showed that DASH scores improved (p<0.05) and the number of words chosen and PRI decreased (p<0.05) on the McGill Pain Questionnaire at post-intervention. Results should be interpreted cautiously, considering the lack of a control group in the investigation. In conclusion, it is suggested that an intervention program consisting of cryotherapy, strengthening, and stretching applied during working hours and twice a week may be effective to decrease pain and physical impairment in male workers with subacromial impingement syndrome.