Anatomical considerations and clinical implications of bicipital aponeurosis: A magnetic resonance imaging study.

The bicipital aponeurosis (BA) is the distal aponeurosis of the biceps brachii which usually covers the median nerve (MN), and the brachial artery (BrA) and sometimes causes compression of these structures. Since these situations are rarely reported in the literature, BA frequently does not come to mind as a cause of such compression. Therefore, the diagnosis may be delayed. In this study, we aimed to investigate the morphometry of BA and its relationship with the surrounding neurovascular structures and to draw attention to BA as a structure that can cause entrapment of the MN and rarely, the BrA. We examined the MRIs of the elbow of 279 patients (107 women, 172 men) aged between 18 and 72 years. We measured the thickness, length and width of BA, and investigated the anatomical relationship between BA, BrA, and MN. The respective median thickness, width, and length of BA were 0.7 (0.4-1.8 mm), 18.0 (6.0-34.0 mm), and 32.0 (18.0-50.0 mm), respectively. In all sections examined, the BA covered the BrA and MN, and was located immediately anterior to the BrA. In 225 (80.6%) of 279 MRIs, the BrA was located anterior to the MN and posterior to the BA. In the remaining 54 (19.4%) MRIs, the MN was located anterior to the BrA and posterior to the BA. The respective median thickness, width, and length of the BA were 0.7 mm, 18.0 mm, and 32.0 mm, respectively. It covered the BrA and MN and was located immediately anterior to the BrA. The BA sometimes causes compression syndromes of these structures, therefore, for physicians, it is important to understand the anatomy of the BA.

Reevaluation of the topographical anatomy of the mid-thigh: A magnetic resonance and ultrasound imaging study.

Adductor canal (AC) and sciatic nerve (SN) blockades are commonly used during total knee arthroplasties for postoperative pain control. Medical professionals have begun to utilize single injection combined regional anesthesia methods due to increased patient comfort. In this study, we examined the topographical anatomy of the mid-thigh, which is recommended as the appropriate intervention level for combined AC and SN blockades, in order to provide a safe approach for clinicians. We examined 184 thigh magnetic resonance images (MRI) from 98 patients. We measured the diameter of the mid-thigh, anterior thigh muscle thickness, subcutaneous adipose tissue thickness, and SN depth on the MRIs. We obtained ultrasound (US) images of the vastoadductor membranes (VAM) of 26 volunteers, and measured the vertical distances between the greater trochanter and the adductor tubercle (A) and the greater trochanter and the upper edge of the VAM (B). We then proportioned B to A in order to determine in which part of the thigh the AC was located. The AC was in the distal third of the thigh, and the SN's depth was located in the third quarter of the thigh's diameter. Only the adductor magnus, and no neurovascular structure, was at risk of injury between the AC and the SN. The upper edge of the VAM was 6.5 cm below the mid-thigh, therefore it is not appropriate to suggest performing an AC blockade at mid-thigh. We think that it is safe to perform a combined AC and SN blockade in a single injection in selected patients.

Prevalence and clinical implications of the Gantzer's muscle.

PURPOSE: The Gantzer's muscle is considered to be the accessory head of the flexor pollicis longus. The prevalence of the Gantzer's muscle and its anatomical relations vary in the literature. So, we aimed to study its prevalence and anatomical relations on a broad population on magnetic resonance (MRI) and ultrasound (US) images. MATERIALS AND METHODS: We investigated a total of 473 upper extremities of 378 people (171 women, 207 men), aged between 18 and 73 years, by MRI and US. We investigated the prevalence and length of the Gantzer's muscle and its anatomical relationship with the median (MN) and anterior interosseous nerves (AIN). RESULTS: Of the 473 extremities, 96 had Gantzer's muscle (20.3%). Overall prevalence of the Gantzer's muscle was 21.9% (51 in 232) in women and 18.7% (45 in 241) in men. In the population we performed US, Gantzer's muscle was located 40.0% in only the right limb, 37.1% in only the left limb and 22.9% bilaterally. All the Gantzer's muscles originated from the coronoid process. Of the 43 Gantzer's muscles seen in US, thirty-four (79.1%) were attached to flexor pollicis longus and nine (20.9%) were attached to flexor digitorum superficialis. The mean length of the Gantzer's muscle was 29.7 (range 17.2-44.5) mm. MN was anterior to the Gantzer's muscle in all extremities except ten. In all extremities, AIN was located posterior to the Gantzer's muscle. CONCLUSION: Although it is seen at a rare rate of 20.3%, Gantzer's muscle should be considered in MN and AIN compressions due to its close proximity to these nerves.

Can Lateral Offset Be Used as a Predictive Marker for Proximal Femur Disorders?

Purpose: When the lateral offset (LO) changes, the forces acting on the head and neck of the femur change. Increase or decrease in LO can cause instability and possible dislocation of the implant. In addition, when the offset is reduced, more force is needed to balance the pelvis by the abductor muscles, and the force that occurs along the hip joint increases and causes wear and tear. In this study we aimed to investigate whether there is a correlation between LO and proximal femur morphology, and according to the results we aimed to investigate whether the LO can be used as a predictive marker for the risk of femoral neck fractures, osteoarthritis or femoroacetabular impingement. Methods: Femur length, femur neck length, femoral neck-shaft angle (NSA), anteroposterior (a-p) and superoinferior (s-i) diameters of femoral head and neck, and LO were measured on 82 dry adult femora of unknown age and gender from Turkish population. Results: There was no statistically significant correlation between the LO and a-p and s-i diameters of femoral head or neck. However, there was found statistically significant correlation between LO and femoral NSA (p < 0.01), femoral neck length (p < 0.05) and femur length (p < 0.01). Conclusion: High LO values can be used as an indicator for neck fractures, a negative marker for OA, but LO does not appear to be used as an indicator for FAI.

Examination of inner ear structures: a micro-CT study.

BACKGROUND: We investigated the inner ear anatomy accurately in detail by microcomputed tomography (micro-CT) to contribute to the data related to the inner ear anatomy and the potential clinical contribution of these data in the treatment of the inner ear's pathologies. AIMS/OBJECTIVES: This study aimed to define a range for normal measurements of the VA, vestibule, lateral semicircular canal, and cochlea. We scanned temporal dry bone samples at high resolution using micro-CT. MATERIAL AND METHODS: Forty dry temporal bones used in anatomy student education were included in this study with a micro-CT device. All measurements were made on sections in the axial plane with micro-CT programs. RESULTS: The operculum and the vestibular aqueduct middle diameters median values were 0.487 mm and 0.294 mm, respectively. The median value of middle diameters for the nonampullated section of lateral semicircular canal was 1.103 mm. The mean height of the cochlea was 3.417 mm and the width of the cochlea was 5.615 mm. The mean length of the vestibule was 6.085 mm and the width of the vestibule was 3.002 mm. CONCLUSIONS AND SIGNIFICANCE: We present a database that clinicians can consider in their studies by creating normal anatomical values measured with high precision for the bone labyrinth.

Morphological characteristics of the posterior neck muscles and anatomical landmarks for botulinum toxin injections.

PURPOSE: Cervical dystonia is a common movement disorder for which botulinum toxin (BoNT) is the first choice treatment. Injecting the specific neck muscles can be challenging because of their thin morphology and deep locations. We, therefore, designed a study to investigate the locations of the posterior neck muscles to help the physician predict the locations of the targeted neck muscles and to protect the vertebral vessels from injury during deep injections. METHODS: The posterior neck region was divided into four quadrants by imaginary lines passing vertically and transversely through the spinous process of C2 vertebra (C2sp). The thicknesses and depth of the posterior neck muscles were measured in ten formaldehyde-fixed adult male cadavers. These muscles were located and a projection of them was drawn on the neck. Using the measurements, colored latex in place of BoNT was injected into them in one cadaver. The cadaver was dissected to investigate whether the muscles were colored. RESULTS: 2 cm above the C2sp, trapezius, splenius capitis (SPC) and semispinalis capitis (SSC) were colored at depths of 10.70 mm, 11.88 mm and 15.91 mm, respectively. 2 cm below the C2sp, the trapezius, SPC and SSC were colored at depths of 20.89 mm, 23.25 mm and 27.63 mm, respectively. The posterior neck muscles were had taken up their assigned colors when they were injected according to the results obtained in this study. The vertebral vessels were not colored. CONCLUSIONS: Although BoNT injection into the posterior neck muscles is challenging, we think that it can be practically and safely applied using the measurements obtained in this study.

Re-defining the anatomical structures for blocking the nerves in adductor canal and sciatic nerve through the same injection site: an anatomical study.

PURPOSE: The aim of this study is to re-define the anatomical structures which are important for blocking the sciatic nerve and the nerves within the adductor canal which innervate the knee joint through the same injection site. We also aimed to investigate the spread of the anesthetic toward the areas in which the mentioned nerves lie on cadavers. METHODS: This study was performed on 16 lower extremities of formaldehyde-embalmed eight adult cadavers. The anatomy of adductor canal, courses of the nerves within the canal and the relationships of the saphenous, medial femoral cutaneous, medial retinacular, posterior branch of the obturator and sciatic nerves with each other and with the fascial compartments were investigated. Transverse sections that crossed the superior border of vastoadductor membrane were taken to reach the sciatic nerve in the shortest way. Colored latex was injected to demonstrate the anesthetic blockage of the targeted nerves. The structures along the needle's way were investigated. RESULTS: The saphenous, medial femoral cutaneous and at its distal part posterior branch of the obturator nerve were colored with latex within the adductor canal. The nerve to vastus medialis (in other words, the medial retinacular nerve) lay beneath the fascia of vastus medialis and did not enter the adductor canal. There was a fascial plane which did not allow the passage of colored latex toward the sciatic nerve. To traverse this fascial structure, it was found out to be necessary to insert the needle perpendicular to both the vertical and transverse axes of the thigh and then advance it along 2/3 of diameter of the thigh. Thus, the colored latex was observed to fill the compartment where the sciatic nerve lay within. CONCLUSIONS: Blocking the sciatic nerve and the nerves within the adductor canal which innervate the knee joint through the same injection site seems anatomically possible without injuring any neurovascular structures.