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JSES International May 2024The deltoid is a trisegmented muscle with anterior, middle, and posterior components. While the clinical relevance of the presence of anatomic variations of the deltoid...
BACKGROUND
The deltoid is a trisegmented muscle with anterior, middle, and posterior components. While the clinical relevance of the presence of anatomic variations of the deltoid origin and insertion continues to be debated, the architecture of the deltoid muscle is more complex than initially believed. This study aimed to evaluate the gross anatomy of the deltoid muscle insertion by qualitatively and quantitatively characterizing the insertion and location of the deltoid muscle's anterior, middle, and posterior components. This information is valuable to surgeons as it raises awareness of potential variants that could be encountered during surgery, promotes mindfulness of neurovascular proximities, and reduces the likelihood of confusion between adjacent muscle fibers.
METHODS
Eight nonpaired, fresh-frozen clavicle-to-fingertip cadaveric shoulders were acquired for the study (6 left, 2 right). The average age of the cadavers was 79.5 years (range: 64-92). The standard deltopectoral approach was carried out on all specimens. The planes dividing the anterior, middle, and posterior deltoid were identified and marked. Once complete exposure had been achieved, digital calipers were used to record the size of the deltoid insertion. The specimens were qualitatively assessed to characterize the style of insertion they demonstrated.
RESULTS
The average length of the deltoid insertion was 39.45 ± 9.33 mm (n = 8). Six of the eight shoulders demonstrated an insertion style previously characterized in the literature. The remaining two shoulders highlighted an insertion pattern not previously described.
CONCLUSION
The current study demonstrates a novel insertion pattern for the deltoid muscle that has not been previously characterized. This "step-off" insertion pattern shows that the anterior, middle, and posterior tendons are inserted superior-medial, directly on, and inferior-lateral to the deltoid tuberosity and was found in 2/8 of our cadaveric specimens.
PubMed: 38707574
DOI: 10.1016/j.jseint.2024.01.013 -
Annals of Nuclear Medicine Apr 2022Reactive FDG uptake in the axillary lymph nodes (ALN) and deltoid muscle (DM) after COVID-19 mRNA vaccination has been recognized, although the actual situation in the...
[F]FDG uptake in axillary lymph nodes and deltoid muscle after COVID-19 mRNA vaccination: a cohort study to determine incidence and contributing factors using a multivariate analysis.
PURPOSE
Reactive FDG uptake in the axillary lymph nodes (ALN) and deltoid muscle (DM) after COVID-19 mRNA vaccination has been recognized, although the actual situation in the Japanese population remains unknown. To determine the incidence of reactive FDG uptake and its contributing factors, we retrospectively studied a cohort of subjects who were vaccinated at our hospital.
METHODS
Whole-body FDG-PET/CT examinations performed in 237 subjects out of 240 subjects with a definite history of COVID-19 vaccination (BNT162b2; BioNTech-Pfizer) were analyzed. Positivity and SUVmax of FDG uptake in the ALN and DM ipsilateral to vaccination, various subject characteristics, and the grade of the pathological FDG-PET/CT findings were evaluated using a multivariate analysis.
RESULTS
FDG uptake in the ALN and DM ipsilateral to vaccination was seen in about 60% of the subjects even soon (0-4 days) after the first vaccination, with percentages reaching 87.5% and 75.0%, respectively, after the second vaccination. DM uptake had almost disappeared at around 2 weeks, while ALN uptake persisted for 3 weeks or longer. A multivariate analysis showed that a short duration since vaccination, a younger age, a female sex, and a low FDG-PET/CT grade (minimal pathological FDG uptake) contributed significantly to positive ALN uptake, while a short duration since vaccination and a female sex were the only significant contributors to positive DM uptake. This study is the first to identify factors contributing to positive FDG uptake in ALN and DM after COVID-19 vaccination.
CONCLUSION
A high incidence of FDG uptake in ALN and DM was observed after vaccination. ALN uptake seemed to be associated with a younger age, a female sex, and minimal pathological FDG uptake. After vaccination, an acute inflammatory reaction in DM followed by immune reaction in ALN linked to humoral immunity may be speculated.
Topics: BNT162 Vaccine; Breast Neoplasms; COVID-19; COVID-19 Vaccines; Cohort Studies; Deltoid Muscle; Female; Fluorodeoxyglucose F18; Humans; Incidence; Lymph Nodes; Multivariate Analysis; Positron Emission Tomography Computed Tomography; RNA, Messenger; Retrospective Studies; Vaccination
PubMed: 35098436
DOI: 10.1007/s12149-021-01711-7 -
BMC Musculoskeletal Disorders Apr 2023Supraspinatus (SSP) strength tests are an important shoulder examination tool for clinical evaluations of patients with a suspected SSP tear. While the empty can (EC)...
BACKGROUND
Supraspinatus (SSP) strength tests are an important shoulder examination tool for clinical evaluations of patients with a suspected SSP tear. While the empty can (EC) test is widely used to diagnose SSP dysfunction, the test cannot selectively activate SSP activity. The aim of this study was to access the electromyographic (EMG) activity within SSP, deltoid, and surrounding periscapular muscles after resisted abduction force to determine which shoulder position helps best isolate SSP from deltoid activity.
METHODS
A controlled laboratory EMG study was conducted. Specifically, we conducted an EMG analysis of the seven periscapular muscles (i.e., the middle deltoid, anterior deltoid, SSP, upper trapezius, posterior deltoid, infraspinatus, and pectoralis major) in 21 healthy participants, without any history of shoulder disorder, aged 29 ± 0.9 years old with a dominant-right arm. EMG activities were measured during resisted abduction force according to comprehensive shoulder positions in abduction, horizontal flexion, and humeral rotation. The supraspinatus to middle deltoid (S:D) ratio was calculated using the standardized weighted EMG and the maximum voluntary isometric contraction of the SSP and middle deltoid muscles, for each shoulder position to determine the best isolated SSP muscle strength test position. Results were analyzed with the Kruskal-Wallis test for non-normally distributed data.
RESULTS
Shoulder abduction, horizontal flexion, and humeral rotation significantly affected the activity of the middle deltoid, SSP, and S:D ratio (P < 0.05). The S:D ratio increased significantly in lower degrees of shoulder abduction, lower degrees of horizontal flexion, and external humeral rotation over internal rotation. The greatest S:D ratio (3.4 (0.5-9.1)) occurred at the shoulder position of 30° shoulder abduction combined with 30° horizontal flexion and external humeral rotation. Conversely, the classic EC position manifested nearly the smallest S:D ratio (0.8 (0.2-1.2)).
CONCLUSION
Application of the SSP strength test in the shoulder position of 30 degrees abduction, 30 degrees horizontal flexion, and external humeral rotation offers the best position to isolate the abducting activity of the SSP from that of the deltoid, which could help with diagnosis among patients with chronic shoulder pain with a suspected SSP tear condition.
Topics: Humans; Adult; Shoulder; Rotator Cuff; Shoulder Joint; Electromyography; Arm
PubMed: 37013546
DOI: 10.1186/s12891-023-06372-3 -
Vaccine: X Apr 2023To estimate the proportion of adult diabetics with a skin to deltoid muscle distance (SDMD) of > 25 mm, representing a distance greater than the standard needle...
OBJECTIVES
To estimate the proportion of adult diabetics with a skin to deltoid muscle distance (SDMD) of > 25 mm, representing a distance greater than the standard needle length used for intramuscular COVID-19 vaccination, and to assess whether anthropometric measurements predict ultrasound SDMD measurements.
DESIGN
Non-interventional cross-sectional study.
SETTING
Single site, non-clinical setting, Wellington, New Zealand.
PARTICIPANTS
One hundred participants (50 females) aged at least 18 years diagnosis with diabetes. All participants completed the study.
MAIN OUTCOME MEASURES
The proportions of participants with a SDMD > 25 mm and a SDMD > 20 mm (indicating that the needle would not have penetrated at least 5 mm into the deltoid, which is considered necessary to ensure deposition of vaccine into muscle); the relationship between anthropometric measurements (body weight, body height, body mass index (BMI), skinfold thickness, arm circumference) and SDMD measured by ultrasound.
RESULTS
The proportion (95 %CI) of participants with a SDMD > 25 mm was 6/100; 6 % (2.2 to 12.6), and the proportion with a SDMD > 20 mm was 11 % (5.6 to 18.8), of which 9/11 had a BMI ≥ 30 kg/m and 9/11 were female. The strongest relationships between anthropometric measurements and SDMD were with arm circumference (r = 0.76, P < 0.001) and BMI (r = 0.73, P < 0.001). Arm circumference and BMI were the best predictors of SDMD measurements with AUC for ROC curves of 0.99 and 0.94 above the 25 mm cut point, 0.97 and 0.89 above the 20 mm cut point respectively.
CONCLUSIONS
The standard needle length of 25 mm is likely to be insufficient to ensure deposition of COVID-19 vaccine within the deltoid muscle in a small but important proportion of obese adults with diabetes. Arm circumference and BMI are simple measurements that could identify those that need a long needle to ensure successful intramuscular vaccine administration.
FUNDING
Ruth Maud Ring Spencer Estate; Health Research Council of New Zealand (Independent Research Organisation).
PubMed: 36536872
DOI: 10.1016/j.jvacx.2022.100248 -
American Journal of Physical Medicine &... Jun 2023Of the many bizarre complications of administration of the COVID 19 vaccine, adhesive capsulitis is almost unheard of, although shoulder injury related to vaccine...
Of the many bizarre complications of administration of the COVID 19 vaccine, adhesive capsulitis is almost unheard of, although shoulder injury related to vaccine administration, which by definition has symptom onset within 48 hrs and is caused by faulty injection technique, has been rarely reported. Nine cases of adhesive capsulitis, five males and four females with a mean age of 48.7 ± 12.7 yrs, presenting within 1 mo of intramuscular Covishield vaccine on the ipsilateral deltoid and fulfilling the standard UK FROST Multicenter Study diagnostic criteria are reported. The mean time interval from vaccination until symptom onset was 12.3 ± 3.1 days, and mean symptom duration was 9.4 ± 2.4 wks. Conventional treatment with nonsteroidal anti-inflammatory drugs, followed by intra-articular steroid injection coupled with suprascapular nerve steroid block, improved the pain score and range of movement in 8 wks. The exact pathogenesis remains an enigma, although mechanisms such as local spread via deltoid muscle microvasculature, nerves, or shoulder injury related to vaccine administration causing secondary adhesive capsulitis have been hypothesized. While adhesive capsulitis is a very common diagnosis in the physiatric outpatient setting, the possible association with Covishield vaccination, the Indian version of the Oxford AstraZeneca recombinant ChAdOx1 nCoV-19 vaccine, is almost absent in existing literature and hence likely to be missed by clinicians, which necessitates this report.
Topics: Male; Female; Humans; Adult; Middle Aged; COVID-19 Vaccines; ChAdOx1 nCoV-19; COVID-19; Bursitis; Shoulder Joint; Vaccination; Shoulder Injuries; Range of Motion, Articular
PubMed: 36722847
DOI: 10.1097/PHM.0000000000002194 -
Molecular Genetics and Metabolism... Sep 2020Glycogen storage disease type XV (GSD XV) is a recently described muscle glycogenosis due to glycogenin-1 () deficiency characterized by the presence of polyglucosan...
Glycogen storage disease type XV (GSD XV) is a recently described muscle glycogenosis due to glycogenin-1 () deficiency characterized by the presence of polyglucosan bodies on muscle biopsy (Polyglucosan body myopathy-2, PGBM2). Here we describe a 44 year-old man with limb-girdle muscle weakness mimicking a limb-girdle muscular dystrophy (LGMD), and early onset exertional myalgia. Neurologic examination revealed a waddling gait with hyperlordosis, bilateral asymmetric scapular winging, mild asymmetric deltoid and biceps brachii weakness, and pelvic-girdle weakness involving the gluteal muscles and, to a lesser extent, the quadriceps. Serum creatine kinase levels were slightly elevated. Electrophysiological examination showed a myopathic pattern. There was no cardiac or respiratory involvement. Whole-body muscle MRI revealed atrophy and fat replacement of the tongue, biceps brachii, pelvic girdle and erector spinae. A deltoid muscle biopsy showed the presence of PAS-positive inclusions that remained non-digested with alpha-amylase treatment. Electron microscopy studies confirmed the presence of polyglucosan bodies. A diagnostic gene panel designed by the Genetic Diagnosis Laboratory of Strasbourg University Hospital (France) for 210 muscular disorders genes disclosed two heterozygous, pathogenic gene mutations (c.304G>C;p.(Asp102His) + c.164_165del). Considering the clinical heterogeneity found in the previously described 38 GYG-1 deficient patients, we suggest that should be systematically included in targeted NGS gene panels for LGMDs, distal myopathies, and metabolic myopathies.
PubMed: 32477874
DOI: 10.1016/j.ymgmr.2020.100597 -
Clinical Anatomy (New York, N.Y.) Nov 2020The innervation pattern of the clavicular head of the deltoid muscle and its corresponding topography was investigated via cadaveric dissection in the present study,...
INTRODUCTION
The innervation pattern of the clavicular head of the deltoid muscle and its corresponding topography was investigated via cadaveric dissection in the present study, focusing on the lateral pectoral nerve.
MATERIALS AND METHODS
Fifty-eight upper extremities were dissected and the nerve supplies to the deltoid muscle and the variability of the lateral pectoral and axillary nerves, including their topographical patterns, were noted.
RESULTS
The clavicular portion of the deltoid muscle received a deltoid branch from the lateral pectoral nerve in 86.2% of cases. Two topographical patterns of the lateral pectoral nerve were observed, depending on the branching level from the brachial plexus: a proximal variant, where the nerve entered the pectoral region under the clavicle, and a distal variant, where the nerve entered the pectoral region from the axillary fossa around the caudal border of the pectoralis minor. These dissection findings were supported by histological confirmation of peripheral nerve tissue entering the clavicular part of the deltoid muscle.
CONCLUSIONS
The topographical variations of the lateral pectoral nerve are relevant for orthopedic and trauma surgeons and neurologists. These new data could revise the interpretation of deltoid muscle atrophy and of thoracic outlet and pectoralis minor compression syndromes. They could also explain the residual anteversion function of the arm after axillary nerve injury and deficiency, which is often thought to be related to biceps brachii muscle function.
Topics: Aged; Aged, 80 and over; Clavicle; Deltoid Muscle; Female; Humans; Male; Thoracic Nerves
PubMed: 31894613
DOI: 10.1002/ca.23555 -
Journal of Human Kinetics Oct 2020The aims of this study were to compare muscle activity of the anterior deltoid, medial deltoid, and posterior deltoid in the bench press, dumbbell fly, shoulder press,...
The aims of this study were to compare muscle activity of the anterior deltoid, medial deltoid, and posterior deltoid in the bench press, dumbbell fly, shoulder press, and lateral raise exercises. Thirteen men experienced in strength training volunteered for the study. Muscle activation was recorded during maximum isometric voluntary contraction (MVIC) for data normalization, and during one set of 12 repetitions with the load of 60% 1RM in all exercises proposed. One-way repeated-measures ANOVA with Bonferroni's posthoc was applied using a 5% significance level. For anterior deltoid, the shoulder press (33.3% MVIC) presented a significantly higher level of activation when compared to other exercises. Also, no significant difference was found between the bench press (21.4% MVIC), lateral raise (21.2% MVIC), and dumbbell fly (18.8% MVIC). For the medial deltoid, the lateral raise (30.3% MVIC) and shoulder press (27.9% MVIC) presented a significantly higher level of activity than the bench press (5% MVIC) and dumbbell fly (3.4% MVIC). Besides, no significant difference was found between the bench press and the dumbbell fly. For the posterior deltoid, the lateral raise (24% MVIC) presented a significantly higher level of activation when compared to other exercises. For the posterior deltoid portion, the shoulder press (11.4% MVIC) was significantly more active than the bench press (3.5% MVIC) and dumbbell fly (2.5% MVIC). Moreover, no significant difference was found between the bench press and the dumbbell fly. In conclusion, the shoulder press and lateral raise exercises showed a higher level of muscle activation in the anterior deltoid and medial deltoid when compared to the bench press and dumbbell fly exercises.
PubMed: 33312291
DOI: 10.2478/hukin-2020-0033 -
Bulletin Du Cancer Jun 2021
Topics: Aged; Antineoplastic Combined Chemotherapy Protocols; Axilla; BNT162 Vaccine; Deltoid Muscle; Female; Fluorodeoxyglucose F18; Humans; Immunization, Secondary; Incidental Findings; Lymphadenopathy; Neoplasm Recurrence, Local; Ovarian Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals
PubMed: 33972089
DOI: 10.1016/j.bulcan.2021.04.002 -
JSES International Sep 2020Rotator cuff (RC) tears are associated with RC muscle atrophy and changes in composition that are crucial to the prognosis of RC repair. The aim of this study was to...
BACKGROUND
Rotator cuff (RC) tears are associated with RC muscle atrophy and changes in composition that are crucial to the prognosis of RC repair. The aim of this study was to characterize muscle fiber composition in the supraspinatus (SS) muscle under tear conditions.
METHODS
Muscle biopsies were obtained from 21 patients undergoing surgery for an RC tendon tear. Biopsies were obtained from the musculotendinous junction of the SS muscle, and control biopsies were harvested from the deltoid muscle (DT). Biopsies were immunohistochemically processed for detection of type 1 (slow type) and type 2 (fast type) fibers and analyzed using unbiased, stereological principles. We counted the total numbers of type 1 and 2 muscle fibers/mm, and fiber diameter was used to estimate muscle fiber atrophy and hypertrophy.
RESULTS
We found significantly more type 2 cells/mm in the SS compared with the DT ( < .01). In addition, we found a significantly higher fraction of type 1 fibers than type 2 fibers in the DT ( < .01), whereas both fiber types were equally present in the SS. The diameters of SS cells were generally smaller than those of DT cells. Atrophy of especially SS type 2 fibers was also demonstrated. Fiber atrophy was more pronounced in men than women.
CONCLUSION
The changes in the composition of SS muscle cell types suggest a shift from type 1 to type 2 muscle fibers and atrophy of both type 1 and 2 fibers. This composition indicates loss of endurance and rapid fatigue of the SS muscle under RC tear conditions.
PubMed: 32939464
DOI: 10.1016/j.jseint.2020.04.016