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Purpose: The present study aimed to demonstrate the intramuscular nerve distribution of the levator scapulae muscle that is responsible for pain and to use this anatomic data to propose possible injection sites. Methods: Twenty levator scapulae muscles were dissected from 16 Korean embalmed cadavers. The intramuscular nerve distribution of the levator scapulae muscle was identified by whole-mount nerve staining to preserve and stain the nerve fibers without damage. Results: The posterior ramus of spinal nerves C3, C4, and C5 innervated the levator scapulae muscles. When the origin and insertion of the muscle were set to 0% and 100%, respectively, most of the intramuscular nerve terminals were located between 30 and 70%. This area may correspond to the cricoid cartilage of the sixth cervical vertebra. Conclusion: Most intramuscular nerve terminals can be found in the middle and distal portions of the levator scapulae muscle. Our findings improve our understanding of the intramuscular nerve distribution of the levator scapulae muscle and will aid in pain management in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the stiffness of the dorsal scapular muscles before and after computer work between individuals with and without neck and shoulder complaints.Methods: Thirty subjects were divided into patient (n = 18) and control (n = 12) groups. The stiffness of the upper trapezius, levator scapulae, and rhomboid major was measured using ultrasound elastography before and after a 30-min typing task. The strain ratio of the muscle to an acoustic coupler was calculated (a lower strain ratio value indicates greater muscle stiffness).Results: At baseline, the strain ratio of the upper trapezius in the patient group (3.762 ± 1.679) (mean ± SD) was significantly lower than that of the control group (7.763 ± 5.921) (p = 0.041). No significant change in the strain ratio of the upper trapezius after the typing task was observed in the patient group (4.158 ± 3.465) (p = 0.549). A significant decrease in the strain ratio of the levator scapulae after the typing task was observed in the patient group (before: 9.006 ± 7.079, after: 5.718 ± 2.847) (p = 0.022), whereas there was no significant change in the control group (p = 0.436).Conclusions: The increase in stiffness of the upper trapezius is an objective finding and may be a persistently altered condition in individuals with neck and shoulder complaints. The patterns of change in stiffness of the levator scapulae are different between individuals with and without neck and shoulder complaints. [ABSTRACT FROM AUTHOR]

Background: The structure and function of the serratus anterior muscle are partitioned into three parts. If the morphological characteristics in each part can be demonstrated in more detail, the cause of dysfunction will probably be identifiable more accurately. The purpose of this study was to demonstrate the details of the structure and innervation in each part of the serratus anterior muscle. Materials and methods: This macroscopic anatomic study was conducted using ten sides from five cadavers. The structure and innervation in each part of this muscle were examined. Results: In the superior part, the independent branch was divided from a branch innervating the levator scapulae muscle. In the middle part, the long thoracic nerve descended on one-third of the anterior region between the origin and insertion. In the inferior part, the long thoracic nerve which ramified into many branches and branches from the intercostal nerves were distributed on all sides. Conclusion: This study demonstrated that the innervation of the serratus anterior muscle was different in each part. The difference indicates that the superior part has an intimate relation with the levator scapulae muscle while the middle and inferior parts could be the actual serratus anterior muscle. Moreover, the distribution of branches from the intercostal nerves shows that the inferior part has a connection with some trunk elements. Understanding these characteristics of innervation is useful to identify the cause of dysfunction. In addition, we assert that the constant distribution of branches from the intercostal nerves is significant for the morphology. [ABSTRACT FROM AUTHOR]