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Journal of Clinical Medicine Feb 2024: The management of acromioclavicular joint injuries requires a thorough understanding of the anatomy and biomechanics of the joint, as well as knowledge of the... (Review)
Review
: The management of acromioclavicular joint injuries requires a thorough understanding of the anatomy and biomechanics of the joint, as well as knowledge of the pertinent physical exam findings and classification to determine an appropriate treatment approach, whether operative or nonoperative. In this article, we present a narrative review of the current state of understanding surrounding these issues. Although there are a large number of options for operative intervention, we additionally present our experience with anatomic coracoclavicular ligament reconstruction (ACCR) with imbrication of the deltoid fascia. : A retrospective review of prospectively collected data on a total of 45 patients who had undergone ACCR between 2003 and 2016 were collected. : We found that improvements were seen in American Shoulder and Elbow Surgeons Score (ASES) (53 ± 19 to 81 ± 23), Simple Shoulder Test (SST) (6 ± 3 to 12 ± 13), Constant-Murley (CM) (60 ± 18 to 92 ± 8), and Rowe (67 ± 14 to 89 ± 11) and the mean post-operative SANE score was 86 ± 17. : ACCR has the advantage of addressing both horizontal and vertical stability with good outcomes.
PubMed: 38592250
DOI: 10.3390/jcm13051413 -
Journal of Clinical Medicine Feb 2024Despite the importance of the deltoid to shoulder biomechanics, very few studies have quantified the three-dimensional shape, size, or quality of the deltoid muscle,...
Impact of Deltoid Computer Tomography Image Data on the Accuracy of Machine Learning Predictions of Clinical Outcomes after Anatomic and Reverse Total Shoulder Arthroplasty.
Despite the importance of the deltoid to shoulder biomechanics, very few studies have quantified the three-dimensional shape, size, or quality of the deltoid muscle, and no studies have correlated these measurements to clinical outcomes after anatomic (aTSA) and/or reverse (rTSA) total shoulder arthroplasty in any statistically/scientifically relevant manner. Preoperative computer tomography (CT) images from 1057 patients (585 female, 469 male; 799 primary rTSA and 258 primary aTSA) of a single platform shoulder arthroplasty prosthesis (Equinoxe; Exactech, Inc., Gainesville, FL) were analyzed in this study. A machine learning (ML) framework was used to segment the deltoid muscle for 1057 patients and quantify 15 different muscle characteristics, including volumetric (size, shape, etc.) and intensity-based Hounsfield (HU) measurements. These deltoid measurements were correlated to postoperative clinical outcomes and utilized as inputs to train/test ML algorithms used to predict postoperative outcomes at multiple postoperative timepoints (1 year, 2-3 years, and 3-5 years) for aTSA and rTSA. Numerous deltoid muscle measurements were demonstrated to significantly vary with age, gender, prosthesis type, and CT image kernel; notably, normalized deltoid volume and deltoid fatty infiltration were demonstrated to be relevant to preoperative and postoperative clinical outcomes after aTSA and rTSA. Incorporating deltoid image data into the ML models improved clinical outcome prediction accuracy relative to ML algorithms without image data, particularly for the prediction of abduction and forward elevation after aTSA and rTSA. Analyzing ML feature importance facilitated rank-ordering of the deltoid image measurements relevant to aTSA and rTSA clinical outcomes. Specifically, we identified that deltoid shape flatness, normalized deltoid volume, deltoid voxel skewness, and deltoid shape sphericity were the most predictive image-based features used to predict clinical outcomes after aTSA and rTSA. Many of these deltoid measurements were found to be more predictive of aTSA and rTSA postoperative outcomes than patient demographic data, comorbidity data, and diagnosis data. While future work is required to further refine the ML models, which include additional shoulder muscles, like the rotator cuff, our results show promise that the developed ML framework can be used to evolve traditional CT-based preoperative planning software into an evidence-based ML clinical decision support tool.
PubMed: 38592118
DOI: 10.3390/jcm13051273 -
Vaccine Apr 2024To improve the efficacy of Plasmodium falciparum malaria vaccine RTS,S/AS02, we conducted a study in 2001 in healthy, malaria-naïve adults administered RTS,S/AS02 in... (Randomized Controlled Trial)
Randomized Controlled Trial
A phase IIa, randomized, double-blind, safety, immunogenicity and efficacy trial of Plasmodium falciparum vaccine antigens merozoite surface protein 1 and RTS,S formulated with AS02 adjuvant in healthy, malaria-naïve adults.
BACKGROUND
To improve the efficacy of Plasmodium falciparum malaria vaccine RTS,S/AS02, we conducted a study in 2001 in healthy, malaria-naïve adults administered RTS,S/AS02 in combination with FMP1, a recombinant merozoite surface-protein-1, C-terminal 42kD fragment.
METHODS
A double-blind Phase I/IIa study randomized N = 60 subjects 1:1:1:1 to one of four groups, N = 15/group, to evaluate safety, immunogenicity, and efficacy of intra-deltoid half-doses of RTS,S/AS02 and FMP1/AS02 administered in the contralateral (RTS,S + FMP1-separate) or same (RTS,S + FMP1-same) sites, or FMP1/AS02 alone (FMP1-alone), or RTS,S/AS02 alone (RTS,S-alone) on a 0-, 1-, 3-month schedule. Subjects receiving three doses of vaccine and non-immunized controls (N = 11) were infected with homologous P. falciparum 3D7 sporozoites by Controlled Human Malaria Infection (CHMI).
RESULTS
Subjects in all vaccination groups experienced mostly mild or moderate local and general adverse events that resolved within eight days. Anti-circumsporozoite antibody levels were lower when FMP1 and RTS,S were co-administered at the same site (35.0 µg/mL: 95 % CI 20.3-63), versus separate arms (57.4 µg/mL: 95 % CI 32.3-102) or RTS,S alone (62.0 µg/mL: 95 % CI: 37.8-101.8). RTS,S-specific lymphoproliferative responses and ex vivo ELISpot CSP-specific interferon-gamma (IFN-γ) responses were indistinguishable among groups receiving RTS,S/AS02. There was no difference in antibody to FMP1 among groups receiving FMP1/AS02. After CHMI, groups immunized with a RTS,S-containing regimen had ∼ 30 % sterile protection against parasitemia, and equivalent delays in time-to-parasitemia. The FMP1/AS02 alone group showed no sterile immunity or delay in parasitemia.
CONCLUSION
Co-administration of RTS,S and FMP1/AS02 reduced anti-RTS,S antibody, but did not affect tolerability, cellular immunity, or efficacy in a stringent CHMI model. Absence of efficacy or delay of patency in the sporozoite challenge model in the FMP1/AS02 group did not rule out efficacy of FMP1/AS02 in an endemic population. However, a Phase IIb trial of FMP1/AS02 in children in malaria-endemic Kenya did not demonstrate efficacy against natural infection.
CLINICALTRIALS
gov identifier: NCT01556945.
Topics: Adult; Child; Humans; Adjuvants, Immunologic; Antibodies, Protozoan; Antigens, Protozoan; Malaria; Malaria Vaccines; Malaria, Falciparum; Merozoite Surface Protein 1; Parasitemia; Plasmodium falciparum; Protozoan Proteins; Double-Blind Method
PubMed: 38584058
DOI: 10.1016/j.vaccine.2024.03.072 -
International Journal of Sports... 2024A strong body of literature has been published outlining muscle activity differences during sports performance in groups of overhead athletes. However, there are limited...
BACKGROUND
A strong body of literature has been published outlining muscle activity differences during sports performance in groups of overhead athletes. However, there are limited studies that have directly compared the muscle activity in overhead athletes with and without history of shoulder injury during functional everyday tasks.
PURPOSE
This study aimed to identify muscle activities across fourteen upper extremity and core muscles during three functional everyday movements in athletes with and without history of shoulder injury.
STUDY DESIGN
Cross-Sectional Study.
METHODS
Thirty-two male overhead throwing athletes (fifteen healthy and seventeen injured) were recruited and completed three everyday functional movements of high elevation, low elevation, and rotation, using their dominant arm to move an object between two fixed positions. Electromyography (EMG) was recorded for fourteen muscles including: biceps brachii, deltoids (anterior, medial, and posterior), trapezius (upper and lower), pectoralis major, latissimus dorsi, serratus anterior, infraspinatus, external obliques, and gluteus maximus (all surface electrodes) and supraspinatus (fine wire electrode). Mixed model repeated measures ANOVA and post-hoc analysis assessed mean muscle activity (%MVC) between groups and each movement phase.
RESULTS
Upper trapezius elicited higher mean activity in healthy athletes during both phases of the arm rotation task (p \< 0.05). No differences between groups were evident for arm elevation tasks. Qualitative analysis of muscle patterns during functional tasks reflected a temporal shift in muscle activation timings and magnitudes between athlete groups, suggesting potential compensatory mechanisms in injured athletes.
CONCLUSION
Injured overhead athletes appear to utilize other upper limb and shoulder girdle muscles to compensate for lower upper trapezius activity during functional everyday tasks.
LEVEL OF EVIDENCE
3.
PubMed: 38576830
DOI: 10.26603/001c.94604 -
Cureus Mar 2024Idiopathic inflammatory myopathies are a widely heterogeneous group of muscle diseases and encompass multiple clinicopathologic entities. Our case presentation describes...
Idiopathic inflammatory myopathies are a widely heterogeneous group of muscle diseases and encompass multiple clinicopathologic entities. Our case presentation describes a 70-year-old male who presented with progressively worsening dyspnea, along with worsening proximal muscle weakness in the bilateral lower extremities. Extensive clinical evaluation revealed a creatine kinase level of 105 IU/L, severe and chronic widespread myopathy seen on electromyography (EMG), and asymmetric but widespread muscle atrophy with fibro-fatty replacement seen on ultrasonography. Muscle biopsy specimen from the left deltoid was suboptimal but demonstrated characteristics that could be consistent with several clinicopathologic diagnoses, including sporadic inclusion body myositis (sIBM), immune-mediated necrotizing myositis (IMNM), antisynthetase syndrome (AS), and direct toxin-induced myopathy. Electron microscopy revealed tubulofilamentous inclusion associated with autophagic debris, finally rendering an accurate diagnosis. This case summary highlights the testing workflow required to diagnose a patient with an inflammatory myopathy and outlines the difficulty in establishing a diagnosis when the workup for an inflammatory myopathy is delayed and the muscle biopsy is suboptimal.
PubMed: 38576668
DOI: 10.7759/cureus.55580 -
The American Surgeon Apr 2024Compartment syndrome (CS) is a well-known surgical emergency with high morbidity including potential long-term disability and limb loss. The most important factor...
Compartment syndrome (CS) is a well-known surgical emergency with high morbidity including potential long-term disability and limb loss. The most important factor determining the degree of morbidity with CS is time to treatment; therefore, early diagnosis and surgery are vital. We present a patient who fell off his bicycle and sustained cervical spine fractures causing near complete quadriplegia. He was found by the road over 12 hours later, so his creatine phosphokinase (CPK) was trended and serial examinations were performed. We identified tight deltoid, trapezius, and latissimus compartments and brought him to the operating room for fasciotomies. Although lab values and compartment pressures can be helpful, they should not guide treatment. It is important to consider atypical sites for CS and complete a head to toe physical examination. Patients should proceed to the operating room if clinical suspicion exists for CS because of the morbidity associated with a missed diagnosis.
PubMed: 38567401
DOI: 10.1177/00031348241241741 -
Clinics in Orthopedic Surgery Apr 2024Glenoid position and inclination are important factors in protecting against scapular notching, which is the most common complication that directly affects the longevity...
BACKGROUND
Glenoid position and inclination are important factors in protecting against scapular notching, which is the most common complication that directly affects the longevity of reverse shoulder arthroplasty (RSA). This study aimed to investigate the biomechanical characteristics of glenosphere orientation, comparing neutral tilt, inferior overhang with an eccentric glenosphere at the same placement of baseplate, and inferior tilt after 10° inferior reaming in the lower part of the glenoid in RSA.
METHODS
Nine cadaveric shoulders were tested with 5 combinations of customized glenoid components: a centric glenosphere was combined with a standard baseplate (group A); an eccentric glenosphere to provide 4-mm inferior overhang than the centric glenosphere was combined with a standard baseplate (group B); a centric glenosphere was combined with a wedge-shaped baseplate tilted inferiorly by 10° with the same center of rotation (group C); an eccentric glenosphere was attached to a wedge-shaped baseplate (group D); and 10° inferior reaming was performed on the lower part of the glenoid to apply 10° inferior tilt, with a centric glenosphere secured to the standard baseplate for simulation of clinical tilt (group E). Impingement-free angles for adduction, abduction, forward flexion, external rotation, and internal rotation were measured. The capability of the deltoid moment arm for abduction and forward flexion, deltoid length, and geometric analysis for adduction engagement were evaluated.
RESULTS
Compared with neutral tilt, inferior tilt at the same position showed no significant difference in impingement-free angle, moment arm capability, and deltoid length. However, group D resulted in better biomechanical properties than a central position, regardless of inferior tilt. Group E demonstrated a greater range of adduction, internal and external rotation, and higher abduction and forward flexion capability with distalization, compared to corresponding parameters for inferior tilt with a customized wedge-shaped baseplate.
CONCLUSIONS
A 10° inferior tilt of the glenosphere, without changing the position of the baseplate, had no benefit in terms of the impingement-free angle and deltoid moment arm. However, an eccentric glenosphere had a significant advantage, regardless of inferior tilt. Inferior tilt through 10° inferior reaming showed better biomechanical results than neutral tilt due to the distalization effect.
Topics: Humans; Arthroplasty, Replacement, Shoulder; Shoulder Joint; Shoulder Prosthesis; Shoulder; Scapula; Range of Motion, Articular; Biomechanical Phenomena
PubMed: 38562639
DOI: 10.4055/cios23217 -
Orthopedic Reviews 2024The deltoid muscle is impacted by common injuries and clinical procedures. This study aims to summarize the anatomy, injuries, and clinical considerations involving the...
BACKGROUND/OBJECTIVE
The deltoid muscle is impacted by common injuries and clinical procedures. This study aims to summarize the anatomy, injuries, and clinical considerations involving the deltoid muscle.
METHOD
A literature search was performed using PubMed and Google Scholar using keywords that focused on the deltoid muscle in the shoulder. Primary research articles and appropriate summary articles were selected for review.
RESULTS
Reduced deltoid muscle function can be caused by axillary nerve injury, rupture of the deltoid itself, or iatrogenic damage to the muscle. The deltoid muscle has an intimate relationship with the axillary nerve and neighboring rotator cuff muscles. Injury to these nearby structures may be masked by compensating deltoid strength. Examination maneuvers in clinic such as the Akimbo Test should be used to isolate the deltoid muscle to determine if the presenting weakness is from the deltoid itself or from other surrounding injury. Additionally, prior to performing clinical procedures, it is important to be cognitive of the injuries that can occur. For example, incisions that extend distally from the acromion should not extend beyond 5-7 cm as this is the common location of the axillary nerve and vaccine administration should take measures to avoid misplaced injections to avoid unnecessary trauma.
CONCLUSION
Deficiency of the deltoid muscle can be debilitating to patients and it is best clinical practice be aware of the anatomy, various causes, tests, and avoidance measures to help diagnose, restore or preserve normal functioning.
PubMed: 38562147
DOI: 10.52965/001c.115352 -
Cureus Feb 2024The anterior subtype of shoulder dislocations constitutes the vast majority that either reduces instantly or is reduced at the point of care with no serious...
The anterior subtype of shoulder dislocations constitutes the vast majority that either reduces instantly or is reduced at the point of care with no serious complexities. The posterior ones are infrequent and inferior and superior dislocations are even more rare. Rupture of the deltoid is considered to be linked with superior dislocation; regardless, very few articles are available pertaining to the mechanism of onset and the management of a superior shoulder dislocation. In the line of traumatic shoulder dislocations, we present a one-year-old neglected case of a 23-year-old male who sustained an open injury over the right outstretched upper arm, abducted at an angle of approximately 45° due to a fall from a height of approximately 18 feet. This unique report outlines the various surgical modalities available, given the patient's late presentation due to neglect.
PubMed: 38558628
DOI: 10.7759/cureus.55245 -
Indian Journal of Orthopaedics Apr 2024The reduction and fixation of Medial humeral calcar is difficult in the treatment of elderly proximal humerus Neer 3 and 4-part fractures with a single lateral locking...
Application of Intramedullary Calcar Support Plate and Lateral Locking Plate in Elderly Patients with Neer 3 and 4-Part Fractures of Proximal Humerus Through a Deltoid Splitting Approach.
BACKGROUND
The reduction and fixation of Medial humeral calcar is difficult in the treatment of elderly proximal humerus Neer 3 and 4-part fractures with a single lateral locking plate. Our study investigated the efficacy of an intramedullary calcar supporting plate combined with a lateral locking plate for the treatment of 3- and 4-part fractures of the proximal humerus in the elderly through a deltoid splitting approach.
METHODS
From June 2022 to December 2022, we treated six elderly patients with Neer 3 and 4-part fractures using proximal humeral intramedullary calcar support plate in combination with lateral locking plate through a deltoid splitting approach. Follow-up time was 6-12 months. Assessment indicators included fracture union, quality of reduction, and complication rate. The Constant-Murley score was used to record shoulder function at 6 months postoperatively.
RESULTS
All 6 patients showed fracture union and anatomic reduction. Constant-Murley score was 79.5 (70-90) at 6 months postoperatively. There was no incision non-healing, internal fixation failure, bone non-union or surgical site infection, secondary surgery, or death. Shoulder impingement occurred in 1 case.
CONCLUSION
Proximal humeral intramedullary calcar support plate combined with lateral locking plate fixation through a deltoid splitting approach can effectively maintain fracture reduction, prevent inversion collapse of humeral head and internal fixation failure, and provide satisfactory clinical results at an early stage.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s43465-024-01098-3.
PubMed: 38544541
DOI: 10.1007/s43465-024-01098-3