-
Journal of Electromyography and... Aug 2023This study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position... (Observational Study)
Observational Study
PURPOSE
This study aimed to quantify the extent to which age was associated with joint position sense (JPS) of the asymptomatic shoulder as measured by joint position reproduction (JPR) tasks and assess the reproducibility of these tasks.
METHODS
120 Asymptomatic participants aged 18-70 years each performed 10 JPR-tasks. Both contralateral and ipsilateral JPR-tasks were evaluated on accuracy of JPR under active- and passive conditions at two levels within the shoulder forward flexion trajectory. Each task was performed three times. In a subgroup of 40 participants, the reproducibility of JPR-tasks was assessed one week after initial measurement. Reproducibility of JPR-tasks was evaluated by both reliability (intra-class correlation coefficients (ICC's)) and agreement (standard error of measurement (SEM)) measures.
RESULTS
Age was not associated with increased JPR-errors for any of the contralateral or ipsilateral JPR-tasks. ICC's ranged between 0.63 and 0.80 for contralateral JPR-tasks, and from 0.32 to 0.48 for ipsilateral tasks, except for one ipsilateral task where the reliability was similar to contralateral tasks (0.79). The SEM was comparable and small for all JPR-tasks, ranging between 1.1 and 2.1.
CONCLUSION
No age-related decline in JPS of the asymptomatic shoulder was found, and good agreement between test and re-test measurements for all JPR-tasks as indicated by the small SEM.
Topics: Humans; Aging; Muscle, Skeletal; Proprioception; Range of Motion, Articular; Reproducibility of Results; Shoulder; Shoulder Joint; Adolescent; Young Adult; Adult; Middle Aged; Aged
PubMed: 37267894
DOI: 10.1016/j.jelekin.2023.102792 -
PeerJ 2022Indoor climbing involves overloading the shoulder girdle, including the rotator cuff and upper trapezius muscles. This on the field study aimed to investigate the...
BACKGROUND
Indoor climbing involves overloading the shoulder girdle, including the rotator cuff and upper trapezius muscles. This on the field study aimed to investigate the effects of repeated climbing bouts on morphological and mechanical measures of the upper trapezius muscle.
MATERIALS AND METHODS
Fifteen experienced male climbers participated in the study. Rate of perceived exertion (RPE), blood lactate concentration ([La]), and stiffness and thickness over four points of the upper trapezius were assessed before and after a repeated climbing exercise. The procedure for the climbing exercise consisted of five climbs for a total time of 5-minutes per climb, followed by a 5-minute rest.
RESULTS
The analysis showed an increase from baseline to after the 3rd climb ( ≤ 0.01) for RPE and after the 5th climb for [La] ( ≤ 0.001). Muscle stiffness and thickness increased at all points (1-2-3-4) after the 5th climb ( ≤ 0.01). We found spatial heterogeneity in muscle stiffness and thickness; muscle stiffness was the highest at Point 4 ( ≤ 0.01), while muscle thickness reached the highest values at points 1-2 (both ≤ 0.01). Moreover, the analysis between the dominant and non-dominant shoulder showed greater stiffness after the 1 climb at Point 1 ( = 0.004) and after the 5 climb at Point 4 ( ≤ 0.001).
CONCLUSIONS
For muscle thickness, the analysis showed significant changes in time and location between the dominant and the non-dominant shoulder. Bilateral increases in upper trapezius muscle stiffness and thickness, with simultaneous increases in RPE and blood lactate in response to consecutive climbs eliciting fatigue.
Topics: Male; Humans; Superficial Back Muscles; Physical Endurance; Lactic Acid; Shoulder; Exercise
PubMed: 36523451
DOI: 10.7717/peerj.14409 -
European Radiology Mar 2023Quantitative MRI techniques, such as diffusion microstructure imaging (DMI), are increasingly applied for advanced tissue characterization. We determined its value in...
OBJECTIVES
Quantitative MRI techniques, such as diffusion microstructure imaging (DMI), are increasingly applied for advanced tissue characterization. We determined its value in rotator cuff (RC) muscle imaging by studying the association of DMI parameters to isometric strength and fat fraction (FF).
METHODS
Healthy individuals prospectively underwent 3T-MRI of the shoulder using DMI and chemical shift encoding-based water-fat imaging. RC muscles were segmented and quantitative MRI metrics (V-ISO, free fluid; V-intra, compartment inside of muscle fibers; V-extra, compartment outside of muscle fibers, and FF) were extracted. Isometric shoulder strength was quantified using specific clinical tests. Sex-related differences were assessed with Student's t. Association of DMI-metrics, FF, and strength was tested. A factorial two-way ANOVA was performed to compare the main effects of sex and external/internal strength-ratio and their interaction effects on quantitative imaging parameters ratios of infraspinatus/subscapularis.
RESULTS
Among 22 participants (mean age: 26.7 ± 3.1 years, 50% female, mean BMI: 22.6 ± 1.9 kg/m), FF of the individual RC muscles did not correlate with strength or DMI parameters (all p > 0.05). Subjects with higher V-intra (r = 0.57 to 0.87, p < 0.01) and lower V-ISO (r = -0.6 to -0.88, p < 0.01) had higher internal and external rotation strength. Moreover, V-intra was higher and V-ISO was lower in all RC muscles in males compared to female subjects (all p < 0.01). There was a sex-independent association of external/internal strength-ratio with the ratio of V-extra of infraspinatus/subscapularis (p = 0.02).
CONCLUSIONS
Quantitative DMI parameters may provide incremental information about muscular function and microstructure in young athletes and may serve as a potential biomarker.
KEY POINTS
• Diffusion microstructure imaging was successfully applied to non-invasively assess the microstructure of rotator cuff muscles in healthy volunteers. • Sex-related differences in the microstructural composition of the rotator cuff were observed. • Muscular microstructural metrics correlated with rotator cuff strength and may serve as an imaging biomarker of muscular integrity and function.
Topics: Male; Humans; Female; Young Adult; Adult; Shoulder; Rotator Cuff; Shoulder Joint; Rotator Cuff Injuries; Magnetic Resonance Imaging; Radiology
PubMed: 36307552
DOI: 10.1007/s00330-022-09202-7 -
American Family Physician Feb 2021
Topics: Emergency Service, Hospital; Female; Humans; Pregnancy; Shoulder; Shoulder Dystocia; Symphysiotomy
PubMed: 33507057
DOI: No ID Found -
BMJ Open Jul 2023To investigate the effect of age-related rotator cuff tears on shoulder strength in a general population cohort. (Observational Study)
Observational Study
OBJECTIVES
To investigate the effect of age-related rotator cuff tears on shoulder strength in a general population cohort.
DESIGN
Cross sectional observational study.
SETTING
This study was set in an outpatient clinic setting in Chingford, North East London, and was a component of the 20 year visit of the Chingford 1000 women cohort.
PARTICIPANTS
Individuals were part of the Chingford 1000 women cohort, a 20-year-old longitudinal population study. This cohort has been extensively characterised as representative of the population of the UK. At the 20 year visit, 446 attended for shoulder assessment and were aged between 64 and 87.
PRIMARY AND SECONDARY OUTCOME MEASURES
Isometric shoulder abduction strength measured using a Nottingham Mecmesin Myometer and the presence of rotator cuff pathology, determined via ultrasound examination (GE voluson i portable ultrasound machine with a 10-16MHz linear probe). Shoulders were classified into normal, abnormal tendon/partial tear, full-thickness tears (>0 and ≤2.5 cm) and full-thickness tears (>2.5 cm). Symptoms were defined using the Oxford Shoulder Score, where an abnormal score was defined as symptomatic.
RESULTS
446 women (891 shoulders) aged 71 (range 65-84) were included in the study. Age, the presence of pain and the non-dominant arm were demonstrated to reduce strength. Rotator cuff tears and pathology had no isolated effect on shoulder strength in those aged under 70. However, in the over 70s full-thickness tears>0 and ≤2.5 cm, and >2.5 cm had mean reductions of 6.3 and 12.7 N, respectively (p<0.001).
CONCLUSION
Rotator cuff tears of all sizes in those aged under 70 were not associated with a loss of shoulder strength. In those aged over 70, strength was reduced by 30% with small and 40% with large full thickness tears. Loss in strength was associated a loss of ability to perform activities of daily living but only for large tears.
Topics: Aged; Humans; Female; Aged, 80 and over; Middle Aged; Young Adult; Adult; Shoulder; Rotator Cuff Injuries; Cross-Sectional Studies; Activities of Daily Living; Rotator Cuff
PubMed: 37460264
DOI: 10.1136/bmjopen-2023-071908 -
Sensors (Basel, Switzerland) Sep 2022Shoulder problems (pain and pathology) are highly prevalent in manual wheelchair users with spinal cord injury. These problems lead to limitations in activities of daily...
Shoulder problems (pain and pathology) are highly prevalent in manual wheelchair users with spinal cord injury. These problems lead to limitations in activities of daily life (ADL), labor- and leisure participation, and increase the health care costs. Shoulder problems are often associated with the long-term reliance on the upper limbs, and the accompanying "shoulder load". To make an estimation of daily shoulder load, it is crucial to know which ADL are performed and how these are executed in the free-living environment (in terms of magnitude, frequency, and duration). The aim of this study was to develop and validate methodology for the classification of wheelchair related shoulder loading ADL (SL-ADL) from wearable sensor data. Ten able bodied participants equipped with five Shimmer sensors on a wheelchair and upper extremity performed eight relevant SL-ADL. Deep learning networks using bidirectional long short-term memory networks were trained on sensor data (acceleration, gyroscope signals and EMG), using video annotated activities as the target. Overall, the trained algorithm performed well, with an accuracy of 98% and specificity of 99%. When reducing the input for training the network to data from only one sensor, the overall performance decreased to around 80% for all performance measures. The use of only forearm sensor data led to a better performance than the use of the upper arm sensor data. It can be concluded that a generalizable algorithm could be trained by a deep learning network to classify wheelchair related SL-ADL from the wearable sensor data.
Topics: Humans; Machine Learning; Shoulder; Upper Extremity; Wearable Electronic Devices; Wheelchairs
PubMed: 36236503
DOI: 10.3390/s22197404 -
PloS One 2023Although young adults regularly perform tablet writing, biomechanics during the tablet writing with different tilt angles has not been studied. The objective of this... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Although young adults regularly perform tablet writing, biomechanics during the tablet writing with different tilt angles has not been studied. The objective of this study was to compare posture, muscle activity, and discomfort at the neck and shoulder between tablet writing with 0° (horizontal) and 30° tablet tilt angles over 40 minutes in healthy young adults.
METHODS
Twenty participants wrote continuously for 40 minutes on a tablet with both tilt angles in a randomized order. Between conditions, there was a 5-minute activity break. Differences in neck and shoulder posture, muscle activity, and discomfort between both tablet tilt angles and changes in the outcomes every 10 minutes over 40 minutes were investigated.
RESULTS
With the tilted tablet, there were lower neck flexion (Z = -4.637, P<0.001), lower shoulder extension (Z = -3.734, P<0.001), and lower neck Visual Analogue Scale (VAS) (left; Z = -4.699, P<0.001 and right; Z = -3.874, P<0.001) as compared to the no tilt condition. However, the right upper trapezius muscle activity was higher in the tilted condition as compared to the no tilt one. Over 40 minutes, the neck VAS (left; χ2(4) = 30.235, P<0.001 and right; χ2(4) = 32.560, P<0.001) and heart rate variability (χ2(4) = 12.906, P = 0.012) showed notable increases after 20 minutes compared to baseline.
CONCLUSION
In conclusion, adjusting the tablet tilt to 30° and limiting time spent to 20 minutes are recommended for young adults during the tablet writing to prevent neck problems.
Topics: Humans; Young Adult; Electromyography; Muscles; Neck; Posture; Shoulder
PubMed: 36952497
DOI: 10.1371/journal.pone.0283521 -
Scientific Reports Jun 2022The acromiohumeral interval (AHI) is a measurement used to determine the superior migration of the humeral head in rotator cuff (RC) tear patients. The purpose of this...
The acromiohumeral interval (AHI) is a measurement used to determine the superior migration of the humeral head in rotator cuff (RC) tear patients. The purpose of this study was to compare the AHI of; supine, upright shoulder radiographs, and magnetic resonance imaging (MRI) of the shoulder. The 86 shoulders were divided into 3 groups that included; (1) non-full thickness tear (50%), (2) full thickness (FT) tear ≤3 cm (33.7%), and (3) FT tear > 3 cm (16.3%). The mean difference of AHI noted was significantly lower in the supine radiographs and MRIs than with the upright (1.34-1.37 mm, 1.62-1.87 mm, respectively). Upright AHI ≤ 7.0 mm had 27.9% sensitivity and 100% specificity in diagnosing FT tears with 64% accuracy (p < 0.001). The supine AHI ≤ 6.5 mm had 32.6% sensitivity, 100.0% specificity, and 66.3% accuracy (p < 0.01). The results revealed the AHI in supine radiographs were significantly lower than upright shoulder radiographs. For AHI ≤ 7 mm in upright shoulder radiographs, this remains as an appropriate diagnostic test for ruling in shoulders with full thickness rotator cuff tears. This value was not relevant for use as the cut point in the supine radiographs and MRIs.
Topics: Humans; Magnetic Resonance Imaging; Radiography; Rotator Cuff Injuries; Shoulder; Shoulder Joint
PubMed: 35672458
DOI: 10.1038/s41598-022-13632-0 -
Journal of Orthopaedic Research :... Sep 2022Neonatal brachial plexus palsy (NBPP) occurs in approximately 1.5 of every 1,000 live births. The majority of children with NBPP recover function of the shoulder....
Neonatal brachial plexus palsy (NBPP) occurs in approximately 1.5 of every 1,000 live births. The majority of children with NBPP recover function of the shoulder. However, the long-term risk of osteoarthritis (OA) in this population is unknown. The purpose of this study was to investigate the development of OA in a mouse model of transient neonatal shoulder paralysis. Neonatal mice were injected twice per week for 4 weeks with saline in the right supraspinatus muscle (Saline, control) and botulinum toxin A (BtxA, transient paralysis) in the left supraspinatus muscle, and then allowed to recover for 20 or 36 weeks. Control mice received no injections, and all mice were sacrificed at 24 or 40 weeks. BtxA mice exhibited abnormalities in gait compared to controls through 10 weeks of age, but these differences did not persist into adulthood. BtxA shoulders had decreased bone volume (-9%) and abnormal trabecular microstructure compared to controls. Histomorphometry analysis demonstrated that BtxA shoulders had higher murine shoulder arthritis scale scores (+30%), and therefore more shoulder OA compared to controls. Articular cartilage of BtxA shoulders demonstrated stiffening of the tissue. Compared with controls, articular cartilage from BtxA shoulders had 2-fold and 10-fold decreases in Dkk1 and BMP2 expression, respectively, and 3-fold and 14-fold increases in Col10A1 and BGLAP expression, respectively, consistent with established models of OA. In summary, a brief period of paralysis of the neonatal mouse shoulder was sufficient to generate early signs of OA in adult cartilage and bone.
Topics: Animals; Animals, Newborn; Botulinum Toxins, Type A; Disease Models, Animal; Mice; Osteoarthritis; Paralysis; Rotator Cuff; Shoulder
PubMed: 34812543
DOI: 10.1002/jor.25225 -
Journal of Orthopaedic Research :... Oct 2022The Patient-Reported Outcomes Measurement Information System Upper Extremity Computer Adaptive Test (PROMIS UE CAT) is a newer patient-reported outcome measure for upper...
The Patient-Reported Outcomes Measurement Information System Upper Extremity Computer Adaptive Test (PROMIS UE CAT) is a newer patient-reported outcome measure for upper extremity physical function. To date, no longitudinal study exists assessing PROMIS UE CAT responsiveness in patients undergoing shoulder arthroplasty. The purpose of this prospective longitudinal study is to report PROMIS UE CAT responsiveness to change and correlation to legacy instruments in patients undergoing total shoulder arthroplasty (TSA). Ninety-six patients (97 shoulders) undergoing TSA completed the PROMIS UE, Oxford Shoulder Score (OSS), American Shoulder and Elbow Surgeons (ASES), and Simple Shoulder Test (SST) preoperatively and postoperatively at 6 weeks, 12 weeks, and after 6 months. Spearman's correlation coefficients (r) were calculated between PROMIS UE and other scores at each time-point. Responsiveness to change was assessed using the effect size (Cohen's d) and standardized response mean compared with the preoperative time-point. Floor and ceiling effects were also assessed. PROMIS UE CAT demonstrated positive responsiveness at all time-points after TSA. It demonstrated excellent correlation (range: 0.68-0.84) with ASES, SST, and OSS at all postoperative time-points, but the correlation was weaker (r < 0.6, except OSS) preoperatively. Only OSS and SST showed ceiling effects at the 6-12-month time-point (16.8% and 18.2%, respectively). PROMIS UE CAT responsiveness to change and strength of correlation with legacy instruments improves with time elapsed after TSA. Further quantification of meaningful responsiveness to change will require estimation of the minimal clinically important difference and substantial clinical benefit for PROMIS UE CAT.
Topics: Arthroplasty, Replacement, Shoulder; Patient Reported Outcome Measures; Prospective Studies; Shoulder; United States
PubMed: 35060155
DOI: 10.1002/jor.25263