Muscle body

Abstract: Background/Aim. The detailed knowledge of the architecture of the upper eyelid is very important in numerous upper eyelid corrective surgeries. The article deals with the detailed anatomy of the major components of the upper lid, which are commonly seen in surgical practice. Methods. This study was conducted on 19 human cadavers (12 adults and 7 infants) without pathologic changes in the orbital region and eyelids. Anatomic microdissection of the contents of the orbita was performed bilaterally on 12 orbits from 6 unfixed cadavers (3 male and 3 female). Micromorphologic investigations of the orbital tissue were performed on 8 en bloc excised and formalin-fixed orbits of infant cadavers. Specimens were fixed according to the Duvernoy method. An intra-arterial injection of 5% mixture of melt formalin and black ink was administered into the carotid arterial system. Using routine fixation, decalcination, dehydration, illumination, impregnation and molding procedures in paraplast, specimens were prepared for cross-sections. Results. The measurement of the muscle length and diameter in situ in 6 nonfixed cadavers (12 orbits) showed an average length of the levator palpbrae superioris (LPS) muscle body of the 42.0 ± 1.41 mm on the right, and 40.3 ± 1.63 mm on the left side. In all the cases, the LPS had blood supply from 4 different arterial systems: the lacrimal, supratrochlear, and supraorbital artery and muscle branches of the ophthalmic artery. The LPS muscle in all the specimens was supplied by the superior medial branch of the oculomotor nerve. The connective tissue associated with the LPS muscle contains two transverse ligaments: the superior (Whitnall’s) and intermuscular transverse ligaments (ITL). The orbital septum in all the specimens originated from the arcus marginalis of the frontal bone, and consisted of two layers - the superficial and the inner layer. In addition, a detailed histological analysis revealed that the upper eyelid’s crease was formed by the conjoined fascia including the fascia of the orbicularis muscle, the superficial layer of the orbital septum, and the aponeurosis of the LPS muscle, as well as the pretarsal fascia. Conclusion. The conducted study provided a valuable morphological basis for biomechanical and clinical considerations regarding blepharoptosis surgery.

Abstract: During routine anatomical dissections two cases of unusually structured abductor digiti minimi muscle were discovered. In the first case, the variant muscle body was composed of three well-defined portions: lateral, intermediate and medial. The three portions fused in a common muscular body that attached to the ulnar side of the base of the fifth proximal phalanx. In the second case, the aberrant muscle was composed of two portions: lateral and medial. Distally, they fused in a common muscular body that distally inserted as in previous case. Because in each one of the cases a portion from the aberrant muscle crossed over the ulnar nerve and artery in the Guyon's canal, both variant abductor digiti minimi muscles could be of clinical interest in differential diagnosis of ulnar nerve entrapment. © IJAV. 2010; 3: 67-69.

Abstract: The main objective of this study was to define and verify anatomo-sonographic landmarks for ultrasound-guided injection of botulinum toxin into the longissimus capitis (LC) and splenius cervicis (SC) muscles. After a preliminary work of anatomical description of the LC and SC muscles, we identified these muscles on two cadavers and then on a healthy volunteer using ultrasound and magnetic resonance imaging (MRI) to establish a radio-anatomical correlation. We defined an anatomo-sonographic landmark for the injection of each of these muscles. The correct positioning of vascular glue into the LC muscle and a metal clip into the SC muscle of a fresh cadaver as verified by dissection confirmed the utility of the selected landmarks. For the LC muscle, the intramuscular tendon of the cranial part of the muscle appears to be a reliable anatomical landmark. The ultrasound-guided injection can be performed within the cranial portion of the muscle, between the intra-muscular tendon and insertion into the mastoid process at dens of the axis level. For the SC muscle, the surface topographic landmarks of the spinous processes of the C4–C5 vertebrae and the muscle body of the levator scapulae muscle seem to be reliable landmarks. From these, the ultrasound-guided injection can be carried out laterally by transfixing the body of the levator scapulae. The study defined two cervical anatomo-sonographic landmarks for injecting the LC and SC muscles.

Abstract: Aims Pubovisceral (PV) muscle tears are associated with pelvic floor disorders. The goal of this study was to determine whether index finger palpatory assessment of PV muscle body integrity through the lateral vaginal wall is a reliable indicator of PV muscle tear severity diagnosed by magnetic resonance imaging (MRI). Methods We studied 85 women, 7 weeks after vaginal birth. All had at least one risk factor for obstetric-related PV muscle tear. The ordinal outcome measure of MRI-documented PV muscle tear was defined as: none, less than 50% unilateral tear, 50% or greater unilateral tear or less than 50% bilateral tear, and 50% or greater bilateral tear. PV muscle body integrity by palpatory assessment was scored on a matrix, with each side scored independently and classified as PV muscle body "present" (assuredly felt), "equivocal" (not sure if felt), or "absent" (assuredly not felt). Proportional odds models were constructed to estimate the relationship between PV muscle body integrity palpatory assessment and MRI-documented PV muscle tears. Results Thirty-five percent of study participants exhibited varying degrees of MRI-documented PV muscle tears. Using palpatory assessment, we identified "PV muscle body present bilaterally" in 20%, "equivocal unilaterally or present contralaterally" in 8%, "equivocal or absent unilaterally" or "equivocal bilaterally" in 62%, and "absent bilaterally" in 9%. The odds ratio for estimating MRI results from palpatory assessment was 3.62 (95% confidence interval = 1.70-7.73, P = 0.001). Conclusions A rapid and inexpensive palpatory assessment in the clinic was highly associated with the risk of MRI-documented PV muscle tear and is a useful component of a clinical assessment.