PMC9768330_01
Ultrasound probe placement and image of the pectoralis major muscle. The pectoralis major muscle is shown at the top of the ultrasound image separated by white "rips" (this fibrillar pattern indicates that the probe and muscle fibers are parallel to each other), and the pleura is shown at the bottom. Asking your patient to breathe in and out helps to identify the pleura which must be avoided when injecting. Turning the ultrasound probe through 90 degrees reveals the different fiber orientation of the pectoralis major and pectoralis minor muscles (pectoralis minor shown in the middle of the ultrasound image, which has small white dots:a starry sky appearance:indicating that the probe is somewhat perpendicular to the direction of muscle fibers.
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F1
Ultrasound probe placement for imaging these muscles is shown in Figures 1, 4, 5.
Ultrasound probe placement and image of the intermediate deltoid (pars acromialis) muscle. The deltoid has a monomorphic appearance with stripes, when the ultrasound probe is placed longitudinally, and dots with facias/tendon-like structures, when the probe is transversally orientated. The injection target to treat retroversion and extension is the posterior part of the deltoid muscle. In the figure, the probe is compressing the arm to show the deltoid muscle at the top and humerus muscle at the bottom of the ultrasound image. To visualize and inject the anterior deltoid, the probe should be slid anteriorly from the position shown; to visualize and inject the posterior deltoid, the probe should be slid posteriorly.
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F2
Ultrasound probe placement for the target muscles is described in Figures 2-4.
Ultrasound probe placement and image of the teres major muscle. The round muscle in the middle of the ultrasound image is the teres major muscle. The ultrasound probe can be turned through 90 degrees to help identification, with the teres major muscle having a striped appearance when the ultrasound probe is placed longitudinally.
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F3
Ultrasound probe placement for the target muscles is described in Figures 2-4.
Ultrasound probe placement and image of the latissimus dorsi muscle. The latissimus dorsi muscle can be located by beginning at the posterior axillary fold and then moving the ultrasound probe down the thorax, about halfway toward the lower thoracic vertebrae. To better distinguish the muscle from the subcutaneous tissue, the probe should be parallel to muscle fiber orientation, thus making its fibrillar pattern apparent. In this anatomical location, the latissimus dorsi will be the most superficial muscle, as shown in the image. Underneath it lies the serratus anterior muscle, also shown in the ultrasound image. Just under the serratus anterior muscle, it is also possible to see one rounder hyperechoic line on the bottom right, which corresponds to a rib, and a more linear hyperechoic line on the bottom left, which corresponds to the pleura. The injection can be performed with the probe either in the longitudinal or transversal orientations, but longitudinal is preferred due to the proximity of the pleura. Multiple injections (two or three) are recommended for the latissimus dorsi due to the size and strength of the muscle.
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F4
Ultrasound probe placement for the target muscles is described in Figures 2-4.
Ultrasound probe placement and image of the subscapularis muscle. The subscapularis is the strongest inner rotator of the shoulder muscles. As the subscapularis muscle is located under the shoulder blade, ultrasound location requires elevation of the arm with probe placement in the axilla pointing toward the shoulder blade. The subscapularis muscle is visible as the striped structure in the ultrasound image, below the subcutaneous tissue at the top of the image. Injection of the subscapularis muscle requires two people:one to hold the arm while the patient is lying supine and one to hold the ultrasound probe and inject. Injecting behind the probe location shown above, aiming away from the thorax and toward the scapula, is the only safe approach as the ultrasound probe protects the thorax, and on the other side of the subscapularis lies the scapula, which cannot be harmed when injecting.
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F5
Ultrasound probe placement for imaging these muscles is shown in Figures 1, 4, 5.
PMC9768330_02
Ultrasound probe placement and image of the intermediate deltoid (pars acromialis) muscle. The deltoid has a monomorphic appearance with stripes, when the ultrasound probe is placed longitudinally, and dots with facias/tendon-like structures, when the probe is transversally orientated. The injection target to treat retroversion and extension is the posterior part of the deltoid muscle. In the figure, the probe is compressing the arm to show the deltoid muscle at the top and humerus muscle at the bottom of the ultrasound image. To visualize and inject the anterior deltoid, the probe should be slid anteriorly from the position shown; to visualize and inject the posterior deltoid, the probe should be slid posteriorly.
fneur-13-1022549-g0002.jpg
PMC9768330_02_fneur-13-1022549-g0002.jpg
F2
Ultrasound probe placement for the target muscles is described in Figures 2-4.
Ultrasound probe placement and image of the teres major muscle. The round muscle in the middle of the ultrasound image is the teres major muscle. The ultrasound probe can be turned through 90 degrees to help identification, with the teres major muscle having a striped appearance when the ultrasound probe is placed longitudinally.
fneur-13-1022549-g0003.jpg
PMC9768330_02_fneur-13-1022549-g0003.jpg
F3
Ultrasound probe placement for the target muscles is described in Figures 2-4.
Ultrasound probe placement and image of the latissimus dorsi muscle. The latissimus dorsi muscle can be located by beginning at the posterior axillary fold and then moving the ultrasound probe down the thorax, about halfway toward the lower thoracic vertebrae. To better distinguish the muscle from the subcutaneous tissue, the probe should be parallel to muscle fiber orientation, thus making its fibrillar pattern apparent. In this anatomical location, the latissimus dorsi will be the most superficial muscle, as shown in the image. Underneath it lies the serratus anterior muscle, also shown in the ultrasound image. Just under the serratus anterior muscle, it is also possible to see one rounder hyperechoic line on the bottom right, which corresponds to a rib, and a more linear hyperechoic line on the bottom left, which corresponds to the pleura. The injection can be performed with the probe either in the longitudinal or transversal orientations, but longitudinal is preferred due to the proximity of the pleura. Multiple injections (two or three) are recommended for the latissimus dorsi due to the size and strength of the muscle.
fneur-13-1022549-g0004.jpg
PMC9768330_02_fneur-13-1022549-g0004.jpg
F4
Ultrasound probe placement for the target muscles is described in Figures 2-4.