Maribel Miguel-Pérez

How to avoid injuries of the superior gluteal nerve.

BACKGROUND Injuries to the superior gluteal nerve are a common complication in hip replacement surgery. They can be avoided with a good anatomical knowledge of the course of the superior gluteal nerve. METHODS We dissected 29 half pelvises of adult cadavers. The distance and the angle from the entry points of branches of the superior gluteal nerve into the deep surface of the gluteus medium and minimus muscles to the midpoint of the superior border of the greater trochanter were measured. RESULTS The dissections revealed that the nerve divided into 2 branches (86.20%) or 3 branches (13.8%). The more caudal branch was responsible for innervation of the tensor fascia latae. CONCLUSIONS A 2-3-cm safe area above the greater trochanter is appropriate to prevent nerve damage.

Is interfascial block with ultrasound-guided puncture useful in treatment of myofascial pain of the trapezius muscle?

ObjectivesUltrasound-guided puncture is indispensable for the injection of local anesthetic in the interfascial space, the space between 2 muscle fasciae. Interfascial infiltration or block may be useful in treating myofascial pain in the trapezius muscle. Methods(1) In 5 cadavers, we studied the diffusion of a physiological saline and latex solution in the interfascial space of the upper muscles of the back, and performed a histological study of the fasciae. (2) We performed an interfascial block in 25 patients with myofascial pain in the trapezius muscle. Depending on the trigger point location, the block was performed between the trapezius and the levator scapulae or between the trapezius and the rhomboideus major. ResultsIn all cadavers, anatomical dissection showed the latex in the interfascial space. The histological study confirmed the presence of nerve structures in the fasciae and in the interfascial space itself. Pain was assessed in all patients on a visual analog scale (VAS) before and after the injection (at rest and in motion). Preinjection: mean VAS 6.4 (at rest) and 7.6 (in motion). Postinjection: mean VAS 1 (at rest) and 1.6 (in motion). DiscussionThe anatomical, histological, and ultrasound findings in the cadaver study confirmed the diffusion of the solution in the interfascial space. Study in patients confirms that the interfascial block in the back musculature can be as effective as in the abdominal musculature. The presence of nerve structures in this space, confirmed by the histological study, seems to explain the pain relief reported by the patients with this interfascial technique.

Anatomical and histological study of human deep fasciae development

PurposeTo characterize the connective tissue found between the subcutaneous adipose tissue and the underlying muscle tissue in different regions and at different stages of human fetal development. We aim to identify its structural similarities to adult deep fascia, and to establish its role in myofascial development.MethodsSamples from the arm, forearm, low back and thigh regions (from sites topographically homologous to the adult deep fascia) of five fetus body donors were obtained to perform gross anatomy dissection and histologic sections. Sections were stained with hematoxylin-eosin and Masson trichrome stain to observe their overall structure. Antiserum to protein S100 was used to analyze the presence and distribution of nerve fibers, and immunohistochemistry processing with Tcf4 marker was used to ensure fibroblast activity.ResultsGross anatomy and histological sections of fetal samples showed the presence of connective tissue topographically and morphologically equivalent to adult deep fasciae. Developing blood vessels and nerves were found evenly distributed within the connective tissue during early development and in the portion adjacent to the muscle at later stages. The presence of Tcf4+ fibroblasts was confirmed in all analyzed mesenchymal connective tissue.ConclusionsDeep fascia is present from week 21 of human development in the lower back and upper and lower limbs. Blood vessels and nerves develop parallel to it and occasionally cross it from the deep to superficial plane. The presence of Tcf4+ fibroblasts in the deep fascia suggests a crucial role for this structure in muscle morphogenesis.

An anatomical and histological study of the structures surrounding the proximal attachment of the hamstring muscles

INTRODUCTION The proximal attachment of hamstring muscles has a very high incidence of injuries due to a wide number of factors and its morphology may be one of the underlying factors as scientific literature points out. The connective tissue component of the attachment of hamstring muscles is not well known. For this reason the aim of this study is to describe the anatomy and histology surrounding the proximal attachment of the hamstring muscles (PAHM) and its direct anatomic relations. METHODS Forty-eight cryopreserved lower limbs have sequentially been studied by means of dissection, anatomical sections and histology. RESULTS All specimens studied presented an annular connective tissue structure that resembles a retinaculum, which covers and adapts to the attachment of hamstring muscles on the ischial tuberosity. CONCLUSION The results show how this retinaculum is continuous with the long head of biceps femoris muscle, however there is a layer of loose connective tissue between the retinaculum and the semitendinosus muscle. Furthermore, this structure receives expansions of the anterior epimysium of the gluteus maximus muscle (GIM).