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PloS One 2017The bench press exercise (BP) plays an important role in recreational and professional training, in which muscle activity is an important multifactorial phenomenon. The... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The bench press exercise (BP) plays an important role in recreational and professional training, in which muscle activity is an important multifactorial phenomenon. The objective of this paper is to systematically review electromyography (EMG) studies performed on the barbell BP exercise to answer the following research questions: Which muscles show the greatest activity during the flat BP? Which changes in muscle activity are related to specific conditions under which the BP movement is performed?
STRATEGY
PubMed, Scopus, Web of Science and Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library were searched through June 10, 2016. A combination of the following search terms was used: bench press, chest press, board press, test, measure, assessment, dynamometer, kinematics and biomechanics. Only original, full-text articles were considered.
RESULTS
The search process resulted in 14 relevant studies that were included in the discussion. The triceps brachii (TB) and pectoralis major (PM) muscles were found to have similar activity during the BP, which was significantly higher than the activity of the anterior deltoid. During the BP movement, muscle activity changes with exercise intensity, velocity of movement, fatigue, mental focus, movement phase and stability conditions, such as bar vibration or unstable surfaces. Under these circumstances, TB is the most common object of activity change.
CONCLUSIONS
PM and TB EMG activity is more dominant and shows greater EMG amplitude than anterior deltoid during the BP. There are six factors that can influence muscle activity during the BP; however, the most important factor is exercise intensity, which interacts with all other factors. The research on muscle activity in the BP has several unresolved areas, such as clearly and strongly defined guidelines to perform EMG measurements (e.g., how to elaborate with surface EMG limits) or guidelines for the use of exact muscle models.
Topics: Electromyography; Exercise; Humans; Muscle Contraction; Muscle, Skeletal; Psychomotor Performance
PubMed: 28170449
DOI: 10.1371/journal.pone.0171632 -
Journal of Anatomy Jan 2019The moment arm of a muscle represents its leverage or torque-producing capacity, and is indicative of the role of the muscle in joint actuation. The objective of this...
The moment arm of a muscle represents its leverage or torque-producing capacity, and is indicative of the role of the muscle in joint actuation. The objective of this study was to undertake a systematic review of the moment arms of the major muscles spanning the glenohumeral joint during abduction, flexion and axial rotation. Moment arm data for the deltoid, pectoralis major, latissimus dorsi, teres major, supraspinatus, infraspinatus, subscapularis and teres minor were reported when measured using the geometric and tendon excursion methods. The anterior and middle sub-regions of the deltoid had the largest humeral elevator moment arm values of all muscles during coronal- and scapular-plane abduction, as well as during flexion. The pectoralis major, latissimus dorsi and teres major had the largest depressor moment arms, with each of these muscles exhibiting prominent leverage in shoulder adduction, and the latissimus dorsi and teres major also in extension. The rotator cuff muscles had the largest axial rotation moment arms regardless of the axial position of the humerus. The supraspinatus had the most prominent elevator moment arms during early abduction in both the coronal and scapular planes as well as in flexion. This systematic review shows that the rotator cuff muscles function as humeral rotators and weak humeral depressors or elevators, while the three sub-regions of the deltoid behave as substantial humeral elevators throughout the range of humeral motion. The pectoralis major, latissimus dorsi and teres major are significant shoulder depressors, particularly during abduction. This study provides muscle moment arm data on functionally relevant shoulder movements that are involved in tasks of daily living, including lifting and pushing. The results may be useful in quantifying shoulder muscle function during specific planes of movement, in designing and validating computational models of the shoulder, and in planning surgical procedures such as tendon transfer surgery.
Topics: Arm; Biomechanical Phenomena; Humans; Movement; Muscle, Skeletal; Range of Motion, Articular; Shoulder Joint
PubMed: 30411350
DOI: 10.1111/joa.12903 -
The Cochrane Database of Systematic... Dec 2019Strength training or aerobic exercise programmes, or both, might optimise muscle and cardiorespiratory function and prevent additional disuse atrophy and deconditioning... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Strength training or aerobic exercise programmes, or both, might optimise muscle and cardiorespiratory function and prevent additional disuse atrophy and deconditioning in people with a muscle disease. This is an update of a review first published in 2004 and last updated in 2013. We undertook an update to incorporate new evidence in this active area of research.
OBJECTIVES
To assess the effects (benefits and harms) of strength training and aerobic exercise training in people with a muscle disease.
SEARCH METHODS
We searched Cochrane Neuromuscular's Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL in November 2018 and clinical trials registries in December 2018.
SELECTION CRITERIA
Randomised controlled trials (RCTs), quasi-RCTs or cross-over RCTs comparing strength or aerobic exercise training, or both lasting at least six weeks, to no training in people with a well-described muscle disease diagnosis.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures expected by Cochrane.
MAIN RESULTS
We included 14 trials of aerobic exercise, strength training, or both, with an exercise duration of eight to 52 weeks, which included 428 participants with facioscapulohumeral muscular dystrophy (FSHD), dermatomyositis, polymyositis, mitochondrial myopathy, Duchenne muscular dystrophy (DMD), or myotonic dystrophy. Risk of bias was variable, as blinding of participants was not possible, some trials did not blind outcome assessors, and some did not use an intention-to-treat analysis. Strength training compared to no training (3 trials) For participants with FSHD (35 participants), there was low-certainty evidence of little or no effect on dynamic strength of elbow flexors (MD 1.2 kgF, 95% CI -0.2 to 2.6), on isometric strength of elbow flexors (MD 0.5 kgF, 95% CI -0.7 to 1.8), and ankle dorsiflexors (MD 0.4 kgF, 95% CI -2.4 to 3.2), and on dynamic strength of ankle dorsiflexors (MD -0.4 kgF, 95% CI -2.3 to 1.4). For participants with myotonic dystrophy type 1 (35 participants), there was very low-certainty evidence of a slight improvement in isometric wrist extensor strength (MD 8.0 N, 95% CI 0.7 to 15.3) and of little or no effect on hand grip force (MD 6.0 N, 95% CI -6.7 to 18.7), pinch grip force (MD 1.0 N, 95% CI -3.3 to 5.3) and isometric wrist flexor force (MD 7.0 N, 95% CI -3.4 to 17.4). Aerobic exercise training compared to no training (5 trials) For participants with DMD there was very low-certainty evidence regarding the number of leg revolutions (MD 14.0, 95% CI -89.0 to 117.0; 23 participants) or arm revolutions (MD 34.8, 95% CI -68.2 to 137.8; 23 participants), during an assisted six-minute cycle test, and very low-certainty evidence regarding muscle strength (MD 1.7, 95% CI -1.9 to 5.3; 15 participants). For participants with FSHD, there was low-certainty evidence of improvement in aerobic capacity (MD 1.1 L/min, 95% CI 0.4 to 1.8, 38 participants) and of little or no effect on knee extension strength (MD 0.1 kg, 95% CI -0.7 to 0.9, 52 participants). For participants with dermatomyositis and polymyositis (14 participants), there was very low-certainty evidence regarding aerobic capacity (MD 14.6, 95% CI -1.0 to 30.2). Combined aerobic exercise and strength training compared to no training (6 trials) For participants with juvenile dermatomyositis (26 participants) there was low-certainty evidence of an improvement in knee extensor strength on the right (MD 36.0 N, 95% CI 25.0 to 47.1) and left (MD 17 N 95% CI 0.5 to 33.5), but low-certainty evidence of little or no effect on maximum force of hip flexors on the right (MD -9.0 N, 95% CI -22.4 to 4.4) or left (MD 6.0 N, 95% CI -6.6 to 18.6). This trial also provided low-certainty evidence of a slight decrease of aerobic capacity (MD -1.2 min, 95% CI -1.6 to 0.9). For participants with dermatomyositis and polymyositis (21 participants), we found very low-certainty evidence for slight increases in muscle strength as measured by dynamic strength of knee extensors on the right (MD 2.5 kg, 95% CI 1.8 to 3.3) and on the left (MD 2.7 kg, 95% CI 2.0 to 3.4) and no clear effect in isometric muscle strength of eight different muscles (MD 1.0, 95% CI -1.1 to 3.1). There was very low-certainty evidence that there may be an increase in aerobic capacity, as measured with time to exhaustion in an incremental cycle test (17.5 min, 95% CI 8.0 to 27.0) and power performed at VO max (maximal oxygen uptake) (18 W, 95% CI 15.0 to 21.0). For participants with mitochondrial myopathy (18 participants), we found very low-certainty evidence regarding shoulder muscle (MD -5.0 kg, 95% CI -14.7 to 4.7), pectoralis major muscle (MD 6.4 kg, 95% CI -2.9 to 15.7), and anterior arm muscle strength (MD 7.3 kg, 95% CI -2.9 to 17.5). We found very low-certainty evidence regarding aerobic capacity, as measured with mean time cycled (MD 23.7 min, 95% CI 2.6 to 44.8) and mean distance cycled until exhaustion (MD 9.7 km, 95% CI 1.5 to 17.9). One trial in myotonic dystrophy type 1 (35 participants) did not provide data on muscle strength or aerobic capacity following combined training. In this trial, muscle strength deteriorated in one person and one person had worse daytime sleepiness (very low-certainty evidence). For participants with FSHD (16 participants), we found very low-certainty evidence regarding muscle strength, aerobic capacity and VO peak; the results were very imprecise. Most trials reported no adverse events other than muscle soreness or joint complaints (low- to very low-certainty evidence).
AUTHORS' CONCLUSIONS
The evidence regarding strength training and aerobic exercise interventions remains uncertain. Evidence suggests that strength training alone may have little or no effect, and that aerobic exercise training alone may lead to a possible improvement in aerobic capacity, but only for participants with FSHD. For combined aerobic exercise and strength training, there may be slight increases in muscle strength and aerobic capacity for people with dermatomyositis and polymyositis, and a slight decrease in aerobic capacity and increase in muscle strength for people with juvenile dermatomyositis. More research with robust methodology and greater numbers of participants is still required.
Topics: Dermatomyositis; Exercise; Exercise Tolerance; Humans; Muscle Strength; Muscular Diseases; Muscular Dystrophies; Muscular Dystrophy, Facioscapulohumeral; Myotonic Dystrophy; Physical Fitness; Polymyositis; Randomized Controlled Trials as Topic; Resistance Training
PubMed: 31808555
DOI: 10.1002/14651858.CD003907.pub5 -
PloS One 2023Blood flow restriction combined with low load resistance training (LL-BFRT) is associated with increases in upper limb muscle strength and size. The effect of LL-BFRT on... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Blood flow restriction combined with low load resistance training (LL-BFRT) is associated with increases in upper limb muscle strength and size. The effect of LL-BFRT on upper limb muscles located proximal to the BFR cuff application is unclear.
OBJECTIVE
The aim of this systematic review was to evaluate the effect of LL-BFRT compared to low load, or high load resistance training (LL-RT, HL-RT) on musculature located proximal to cuff placement.
METHODS
Six electronic databases were searched for randomized controlled trials (RCTs). Two reviewers independently evaluated the risk of bias using the PEDro scale. We performed a meta-analysis using a random effects model, or calculated mean differences (fixed-effect) where appropriate. We judged the certainty of evidence using the GRADE approach.
RESULTS
The systematic literature searched yielded 346 articles, of which 9 studies were eligible. The evidence for all outcomes was of very low to low certainty. Across all comparisons, a significant increase in bench press and shoulder flexion strength was found in favor of LL-BFRT compared to LL-RT, and in shoulder lean mass and pectoralis major thickness in favor of the LL-BFRT compared to LL-RT and HL-RT, respectively. No significant differences were found between LL-BFRT and HL-RT in muscle strength.
CONCLUSION
With low certainty LL-BFRT appears to be equally effective to HL-RT for improving muscle strength in upper body muscles located proximal to the BFR stimulus in healthy adults. Furthermore, LL-BFRT may induce muscle size increase, but these adaptations are not superior to LL-RT or HL-RT.
Topics: Adult; Humans; Blood Flow Restriction Therapy; Regional Blood Flow; Muscle, Skeletal; Quadriceps Muscle; Exercise Therapy; Muscle Strength; Resistance Training
PubMed: 36952451
DOI: 10.1371/journal.pone.0283309 -
Cureus Oct 2023The pathology of the shoulder is among the most widespread medical presentations and may be a result of existing anatomical variations. Therefore, the knowledge of the... (Review)
Review
The pathology of the shoulder is among the most widespread medical presentations and may be a result of existing anatomical variations. Therefore, the knowledge of the variations is vital for physicians and clinicians, tasked with treating patients presenting similar complaints to minimize misdiagnosis and prevent iatrogenic injuries. Therefore, the main objective of the present systematic review the variations in pectoralis minor muscle origin and insertion/attachment point. The study also seeks to better inform physicians and clinicians of the task of treating patients with various pathology problems and to ascertain that, upon identification, the pectoralis minor muscle variants are aptly appreciated. The search method used in this systematic review entails the use of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, and the searching of several online databases, for studies focusing on variations in pectoralis minor muscles. The author reviewer evaluated the studies for eligibility, and the selection criteria for the studies used are described below. This systematic review has disclosed that, in some individuals, the pectoralis minor muscles have their origins in the second, third, and fourth ribs, even as others have their origin in the third and fourth ribs. Still, the systematic review has disclosed that, in certain individuals, the insertion of the pectoralis minor muscle occurs at the supraspinatus tendon, even as there are anomalies in the pectoralis minor insertion points linked to subacromial impingement, possible compression of the brachial plexus anteromedial and the axillary artery, and the subcoracoid impingement.
PubMed: 37916251
DOI: 10.7759/cureus.46329 -
Anesthesiology Sep 2019Thoracic paravertebral block is the preferred regional anesthetic technique for breast cancer surgery, but concerns over its invasiveness and risks have prompted search... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Thoracic paravertebral block is the preferred regional anesthetic technique for breast cancer surgery, but concerns over its invasiveness and risks have prompted search for alternatives. Pectoralis-II block is a promising analgesic technique and potential alternative to paravertebral block, but evidence of its absolute and relative effectiveness versus systemic analgesia (Control) and paravertebral block, respectively, is conflicting. This meta-analysis evaluates the analgesic effectiveness of Pectoralis-II versus Control and paravertebral block for breast cancer surgery.
METHODS
Databases were searched for breast cancer surgery trials comparing Pectoralis-II with Control or paravertebral block. Postoperative oral morphine consumption and difference in area under curve for pooled rest pain scores more than 24 h were designated as coprimary outcomes. Opioid-related side effects, effects on long-term outcomes, such as chronic pain and opioid dependence, were also examined. Results were pooled using random-effects modeling.
RESULTS
Fourteen randomized trials (887 patients) were analyzed. Compared with Control, Pectoralis-II provided clinically important reductions in 24-h morphine consumption (at least 30.0 mg), by a weighted mean difference [95% CI] of -30.5 mg [-42.2, -18.8] (P < 0.00001), and in rest pain area under the curve more than 24 h, by -4.7cm · h [-5.1, -4.2] or -1.2cm [-1.3, -1.1] per measurement. Compared with paravertebral block, Pectoralis-II was not statistically worse (not different) for 24-h morphine consumption, and not clinically worse for rest pain area under curve more than 24 h. No differences were observed in opioid-related side effects or any other outcomes.
CONCLUSIONS
We found that Pectoralis-II reduces pain intensity and morphine consumption during the first 24 h postoperatively when compared with systemic analgesia alone; and it also offers analgesic benefits noninferior to those of paravertebral block after breast cancer surgery. Evidence supports incorporating Pectoralis-II into multimodal analgesia and also using it as a paravertebral block alternative in this population.
Topics: Analgesia; Breast Neoplasms; Female; Humans; Nerve Block; Pain, Postoperative; Pectoralis Muscles
PubMed: 31408448
DOI: 10.1097/ALN.0000000000002822 -
Sports Health 2019Pectoralis major tendon ruptures are becoming increasingly common due to the growing prevalence of active lifestyles. Studies investigating the efficacy of pectoralis...
CONTEXT:
Pectoralis major tendon ruptures are becoming increasingly common due to the growing prevalence of active lifestyles. Studies investigating the efficacy of pectoralis major tendon repair have limited sample sizes and offer mixed results, while existing reviews do not explore postoperative activity outcomes for patients.
OBJECTIVE:
To summarize and synthesize the clinical outcomes and rate of return to activity after isolated pectoralis major tendon repair.
DATA SOURCES:
Four databases (MEDLINE, EMBASE, PubMed, and CINAHL) were searched from database inception through March 7, 2018.
STUDY SELECTION:
Studies reporting outcomes of isolated pectoralis major tendon repair for pectoralis major tendon rupture were included.
STUDY DESIGN:
Systematic review.
LEVEL OF EVIDENCE:
Level 4.
DATA EXTRACTION:
Data including patient demographics, intervention details, and clinical outcomes were extracted. The methodological quality of included studies was evaluated.
RESULTS:
Of 2332 retrieved articles, 18 studies were included, with a total of 536 patients. A majority (90%; 134/149) of patients undergoing pectoralis major tendon repair successfully returned to sport at a mean 6.1 ± 1.7 months postsurgery, of which 74% (95/128) successfully returned to their preinjury level of sport. The majority (95%; 269/284) of patients returned to work at a mean 6.9 ± 1 months. Postsurgically, 81% (83/102) of patients experienced complete pain relief after the surgery, and 19% (21/109) had cosmetic complaints after pectoralis major repair. Of the 10 studies that reported complications, 18% (75/423) of patients had postoperative complications, including reruptures and wound infections; 7% (30/423) of patients required reoperation for their complications.
CONCLUSION:
Pectoralis major tendon repair is an effective treatment that results in a high rate of return to sport and work, pain relief, and improved cosmetic appearance, albeit with a significant rate of complication. The evidence supporting all outcomes was limited by the rarity of the injury, the variable surgical techniques, and outcome assessment criteria.
Topics: Esthetics; Humans; Musculoskeletal Pain; Patient Satisfaction; Pectoralis Muscles; Postoperative Complications; Return to Sport; Rupture; Tendon Injuries; Treatment Outcome
PubMed: 30543493
DOI: 10.1177/1941738118818060 -
Annals of Vascular Surgery Oct 2023The optimal diagnostic and treatment algorithm for patients with suspected thoracic outlet syndrome (TOS) remains challenging. Botulinum toxin (BTX) muscle injections... (Review)
Review
BACKGROUND
The optimal diagnostic and treatment algorithm for patients with suspected thoracic outlet syndrome (TOS) remains challenging. Botulinum toxin (BTX) muscle injections have been suggested to shrink muscles in the thoracic outlet reducing neurovascular compression. This systematic review evaluates the diagnostic and therapeutic value of BTX injections in TOS.
METHODS
A systematic review of studies reporting BTX as a diagnostic or therapeutic tool in TOS (or pectoralis minor syndrome as TOS subtype) was conducted in PubMed, Embase, and CENTRAL databases on May 26, 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed. Primary end point was symptom reduction after primary procedure. Secondary end points were symptom reduction after repeated procedures, the degree of symptom reduction, complications, and duration of clinical effect.
RESULTS
Eight studies (1 randomized controlled trial [RCT], 1 prospective cohort study, and 6 retrospective cohort studies) were included reporting 716 procedures in at least 497 patients (at minimum 350 primary and 25 repeated procedures, residual unclear) diagnosed with presumably only neurogenic TOS. Except for the RCT, the methodological quality was fair to poor. All studies were designed on an intention to treat basis, one also investigated BTX as a diagnostic tool to differentiate pectoralis minor syndrome from costoclavicular compression. Reduction of symptoms was reported in 46-63% of primary procedures; no significant difference was found in the RCT. The effect of repeated procedures could not be determined. Degree of symptom reduction was reported by up to 30-42% on the Short-form McGill Pain scale and up to 40 mm on a visual analog scale. Complication rates varied among studies, no major complications were reported. Symptom relief ranged from 1 to 6 months.
CONCLUSIONS
Based on limited quality evidence, BTX may provide short-lasting symptom relief in some neurogenic TOS patients but remains overall undecided. The role of BTX for treatment of vascular TOS and as a diagnostic tool in TOS is currently unexploited.
Topics: Humans; Treatment Outcome; Thoracic Outlet Syndrome; Algorithms; Databases, Factual; Botulinum Toxins
PubMed: 37236533
DOI: 10.1016/j.avsg.2023.05.009 -
JSES Reviews, Reports, and Techniques Nov 2022There is no consensus on whether to repair the subscapularis in the setting of reverse total shoulder arthroplasty (rTSA). There have been an assortment of studies... (Review)
Review
HYPOTHESIS/BACKGROUND
There is no consensus on whether to repair the subscapularis in the setting of reverse total shoulder arthroplasty (rTSA). There have been an assortment of studies showing mixed results regarding shoulder stability and postoperative strength outcomes when looking at subscapularis repair in rTSA. The purpose of this systematic review was to investigate differences in biomechanical strength outcomes of cadaveric subscapularis repair vs. no repair in rTSA.Increased force will be required to move the shoulder through normal range of motion (ROM) in cadaveric rTSA shoulders with the subscapularis repaired when compared with no subscapularis repair.
METHODS
A comprehensive literature review was conducted in accordance with the 2009 Preferred Reporting Items for Systematic Review and Meta-Analysis statement. The databases used to search the keywords used for the concepts of subscapularis, reverse total shoulder arthroplasty, and muscle strength were PubMed (includes MEDLINE), Embase, Web of Science, Cochrane Reviews and Trials, and Scopus. Original, English-language cadaveric studies evaluating rTSA and subscapularis management were included, with subscapularis repair surgical techniques and strength outcomes being evaluated for each article meeting inclusion criteria.
RESULTS
The search yielded 4113 articles that were screened for inclusion criteria by 4 authors. Two articles met inclusion criteria and were subsequently included in the final full-text review. A total of 11 shoulders were represented between these 2 studies. Heterogeneity of the data across the 2 studies did not allow for meta-analysis. Hansen et al found that repair of the subscapularis with rTSA significantly increased the mean joint reaction force and the force required by the posterior deltoid, total deltoid, infraspinatus, teres minor, total posterior rotator cuff, and pectoralis major muscles. Giles et al found that rotator cuff repair and glenosphere lateralization both increased total joint load.
CONCLUSION
The present review of biomechanical literature shows that repair of the subscapularis in the setting of rTSA can effectively restore shoulder strength by increasing joint reactive forces and ROM force requirements of other rotator cuff muscles and of the deltoid muscle. Available biomechanical evidence is limited, and further biomechanical studies evaluating the strength of various subscapularis repair techniques are needed to evaluate the effects of these techniques on joint reactive forces and muscle forces required for ROM.
PubMed: 37588468
DOI: 10.1016/j.xrrt.2022.05.006 -
In Vivo (Athens, Greece) 2023Silicone implants or tissue expanders placed under the pectoralis major (PM) muscle are often used for breast reconstruction. However, the disruption of PM insertions,... (Review)
Review
Silicone implants or tissue expanders placed under the pectoralis major (PM) muscle are often used for breast reconstruction. However, the disruption of PM insertions, which is often an inevitable part of the surgical procedure, is known to cause PM morbidity and, subsequently, problems with the use of the ipsilateral arm. In this systematic review, we present current knowledge regarding the effect of submuscular silicone-based breast reconstruction on the function of PM and the ipsilateral arm. A search of the relevant English literature was performed through PubMed and ten eligible studies were identified. Articles reporting breast augmentation were accepted as the techniques of implant insertion are similar to reconstruction. Questionnaires reporting the status of the arm, analysis of the range of motion of the shoulder with 3-D video, isometric or isokinetic dynamometry, ultrasound shear-wave elastography, volumetric MRI, electromyography and light and electron microscopy of the PM fibers were used for the assessment of PM and arm status. The insertion of implants under the PM, especially when combined with dissection of some of its insertions, seems to be associated with measurable abnormal microscopic, imaging, and dynamometric findings. However, the intact part of the muscle and possibly other nearby muscular structures are able to compensate for the lost part of PM. Thus, the insertion of implants fully or partially under the PM seems to have no or little effect on the function of the ipsilateral upper limb in daily life.
Topics: Pectoralis Muscles; Silicones; Mammaplasty; Prostheses and Implants; Magnetic Resonance Imaging; Breast Implants
PubMed: 37652471
DOI: 10.21873/invivo.13289