The morphologic and morphometric features of the triquetrum.

Fractures of the triquetrum are the second most common form of isolated carpal bone fracture after the scaphoid. However, data on triquetrum morphology and morphometry are sparse. The aim of this study was to describe the morphology of triquetrum using anatomical landmarks, evaluate its morphometric features, and determine its vascular entry points. The morphological and morphometrical features of 87 adult dry triquetral bones (39 left, 48 right) were determined by measuring length, width and thickness. The number and locations of nutrient foramina wider than 0.5 mm were recorded. Mean length, width and thickness were 17.37 mm (range, 14.26-22.13), 12.65 mm (range, 10.37-15.85) and 11.41 mm (range, 8.98-18.23), respectively. The facet articulating with the pisiform was oval in 40 bones, round in 8 and amorphous (neither round nor oval) in 39. The mean length of the interarticular ridge was 7.09 ± 0.9 mm. The mean number of nutrient foramina was significantly greater on the dorsal than on the other aspects. The dorsal predominance of nutrient foramina makes the bone weaker in the dorsal region, which could explain why fractures are more common in this region. Also, the dorsal aspect is rich in blood supply, which could explain why avascular necrosis is less common in triquetral fractures. As most of the vascularization is on the dorsal side, there is need for caution when performing triquetrum surgery. LEVEL OF EVIDENCE: Level 2.

Role of anatomic variations of paranasal sinuses on the prevalence of sinusitis: Computed tomography findings of 350 patients.

OBJECTIVE: The aim of this study was to determine the frequency of anatomic variations of the paranasal sinuses and their roles in the development of sinusitis. MATERIALS AND METHODS: Computed tomography of paranasal sinuses of 350 patients was assessed in terms of anatomic variations and inflammatory sinus pathology. The coexistence of anatomic variations with sinusitis was statistically investigated. RESULTS: At least one anatomical variation of paranasal sinuses was detected in 325 patients (92.9%). In 297 (91.4%) of these patients, sinusitis was observed at rates varying depending on the types of anatomic variations. A statistically significant relationship was found between agger nasi cells, Onodi cells, hypertrophy of middle concha, concha bullosa, uncinate bulla, and the medial and lateral deviations of uncinate process and sinusitis. On the other hand, there was no statistically significant relationship between septal deviation, paradoxical middle concha, secondary middle concha, great ethmoidal bulla, and sinusitis. CONCLUSION: Certain types of paranasal sinus variations create a susceptibility to sinusitis.

Medicolegal aspects of rhinology practice.

OBJECTIVE: To investigate rhinology-related malpractice claims with the aim of optimising safe practice. METHODS: The database of the National Institute of Forensic Medicine was reviewed. In total, 241 otorhinolaryngology malpractice case reports dating from 2005 to 2012 were evaluated, and 83 malpractice cases related to rhinology treatments were separated. RESULTS: There was no significant difference between the number of male (n = 42) and female (n = 41) claimants. The mean patient age was 32.07 ± 10.53 years (range, 10-75 years). Seventy-nine cases involved surgical treatment in rhinology. The most common complaints were: unsatisfactory cosmetic results (n = 30), optic nerve injury (n = 10), septal perforation (n = 9) and intracranial penetration (n = 4). Malpractice was detected in 21 cases (25.3 per cent). No delinquency was found in 62 cases (74.7 per cent). CONCLUSION: Physicians should be aware of legal consequences related to rhinology practice. Further study is needed on this topic, as well as interdisciplinary collaboration, to ensure best practices and to avoid litigation.

The topographic anatomy of the masseteric nerve: A cadaveric study with an emphasis on the effective zone of botulinum toxin A injections in masseter.

INTRODUCTION: Botulinum toxin injections are previously reported to be a noninvasive alternative method for treating masseteric hypertrophy. However, there is a debate on finding an ideal place for injection. The aim of this study is to document the anatomical landmarks for defining the motor nerve entry points (MNEPs) of the masseteric nerve in the masseter for effective botulinum toxin injections. MATERIALS AND METHODS: Twelve sides from six adult fixed cadavers were used for this study. The MNEPs of the masseteric nerve were defined according to standard landmark lines including the orbitomeatal line (OML) and the line (VL), which intersects the mid-distance of the OML to the tip of the angle of the mandible. RESULTS: All MNEPs were located 4.4 cm inferior to the OML. In addition, the average anterior distance of the MNEPs to the VL was 1.4 cm and the average posterior distance was 0.6 cm. CONCLUSION: The ideal site of Botox injection into the masseter is a rectangular area: 5 cm inferior to the OML, 1 cm anterior and posterior to the VL, and just above the periosteum. Based on the data of our study, injections to the parotid gland and branches of the facial nerve such as the marginal mandibular and buccal can be avoided. The masseteric nerve can easily be found approximately 1.0-1.5 cm inferior to the zygomatic arch, 1 cm medial to the temporomandibular joint capsule, and 1 cm superior to mandibular notch, which makes its use for facial reanimations more efficient.

The gluteal sling: an anatomical study.

INTRODUCTION: Sciatic nerve palsy is a devastating complication which may be seen after acetabular exposure in total hip resurfacing via a posterior approach. An anatomical structure termed as the "gluteal sling" was suggested to play a role in sciatic nerve palsies during this operation. "Gluteal sling" is formed by the attachment of the deep fibers of the inferior part of the gluteus maximus on the gluteal tuberosity of the femur and the lateral intermuscular septum. It is suggested to be released to avoid such compressive injuries. The purpose of this study is to demonstrate how much of the gluteal sling should be released to decrease the tension on sciatic nerve during posterior hip arthroplasties. We also aimed to study the anatomical structures at risk during releasing procedure. MATERIALS AND METHODS: The gluteal sling was examined in 17 sides of 9 adult cadavers. Its relation with the sciatic nerve, first perforating artery, the tip of greater trochanter and the ischial tuberosity were evaluated. RESULTS: The closest distance between the gluteal sling and the sciatic nerve was measured as 1.9 ± 0.6 cm. This point was corresponding to the distal 2/3 part of the gluteal sling. The distance of the proximal edge of the gluteal sling to the first perforating artery was 3.7 ± 0.9 cm, while its ascending branch was closer, being 1.8 ± 0.8 cm. CONCLUSIONS: Theoretically, it is enough to release the proximal 2/3 of the gluteal sling to avoid its compression on the sciatic nerve. However, further clinical studies would need to be undertaken to properly determine the effects of this procedure.

A review of the T2 segment of the brachial plexus.

Although the complex architecture of the brachial plexus (BP) has been described for decades, recent literature still aims to elucidate the variation in nerve root contributions to the BP. Understanding this variability in the nerve morphology of the BP may assist physicians and surgeons in the diagnosis and management of certain clinical conditions that involve the BP, either directly or indirectly due to its close association with neighbouring structures. In this article, we review the current anatomical knowledge of the BP, focusing especially on its T2 contribution, and discuss the causes and consequences of some relevant BP pathologies.

Princeps pollicis artery arising from the superficial palmar arch.

We present a 48-year-old male cadaver in which the right superficial palmar arterial arch had no contribution from the radial artery and terminated by giving rise to a common trunk for the princeps pollicis and radialis indicis arteries. The dorsal radial artery of the thumb was absent and no arterial supply was provided by the radial artery. Accordingly, the entire arterial supply to the right thumb was provided by the superficial palmar arterial arch, which was composed solely of the ulnar artery, which received no collateral supply from the radial artery system. Considering that the arterial supply of the thumb in the present case was solely provided by the superficial palmar arch, a potential hazard could exist in the event of traumatic injury to the ulnar artery.

Morphologic variation of the diaphragmatic crura: a correlation with pathologic processes of the esophageal hiatus?

The contributions of muscle fibers from the right and left diaphragmatic crura to the formation of the esophageal hiatus have been documented in several studies, none coming to a complete consensus on the number of anatomic variations or the prevalence of these variations in the human population. These variations may play a role in the pathogenicity of specific diseases that involve the esophageal hiatus, such as hiatal hernias. We examined a total of two hundred adult cadavers during 2000-2007. The variations in the diaphragmatic crura, particularly their muscular contributions to the formation of the esophageal hiatus, were grossly examined and revealed a bilateral occurrence of diaphragmatic crura in all 200 specimens. The results of the various morphological patterns of circumferential muscle fibers forming the esophageal hiatus were classified into six groups. The most common type (Type I, 45%) formed the esophageal hiatus from muscular contributions arising solely from the right crus. In Type II (20%) the esophageal hiatus was formed by muscular contributions from the right and left crura. In Type III (15%), the right and left muscular contributions arose from the right crus with an additional band from the left crus. Type IV (10%) showed that the right and left muscular contributions arose from the right crus, with two additional (anterior and posterior) bands arising from the left crus. Type V (5%) demonstrated the contributions arising solely from the left crus. In Type VI (5%) the right and left contributions originated from the left crus with two additional bands, one from the right crus and one from the left crus. These variations may play a role in the pathogenicity of specific diseases that involve the esophageal hiatus such as hiatal hernia, gastroesophageal reflux disease and Dunbar's syndrome.

Popliteal artery aneurysms: a review.

Popliteal artery aneurysms (PAAs) are the most common form of peripheral arterial aneurysms. The popliteal artery is the continuation of the femoral artery and represents the major source of blood to the leg. Thrombus formation as a result of PAA may reduce blood flow, leading to limb-threatening ischemia and potential limb amputation. Popliteal artery aneurysms are predominantly seen in males (95-99% of cases), presumably owing to their predisposition for arteriosclerosis, which is also a major factor for PAA predisposition. Additionally, it is not uncommon to see an abdominal aortic aneurysm associated with a PAA (30-50% of cases) or bilateral presentation of PAA (approximately 50% of cases). A consequence of a PAA and thrombus located in the popliteal fossa is an inflammatory reaction, potentially involving adjacent structures in the fossa. This may present clinically as pain in the leg and/or edema. Treatment of PAA involves either a conservative management protocol or a more aggressive intervention such as surgery. Proponents of conservative management will regulate the diameter of the aneurysm by ultrasound, while those in favor of surgical intervention will repair the aneurysm through a number of open surgical methods or by endovascular stent grafting. This review summarizes the historical points related to PAA and analyzes the pertinent anatomical implications, clinical findings and treatment methods for PAA.

Evaluation of the anterior and posterior ethmoidal canal by computed tomography.

AIM: To examine the anatomy, length and angulation of the anterior and posterior ethmoidal canals (AECs and PECs) using computed tomography (CT), and to determine the anatomical landmarks in which the canals are expected to be seen in transverse and coronal planes. MATERIALS AND METHODS: CT images of 150 patients were analysed. One, 2, and 3 mm thick sections were obtained separately in axial and coronal images. The frequency of visualization of the AECs and PECs, and if present, a third canal, was noted. The course and the angulation of the AEC and the PEC in transverse and coronal planes were recorded. On axial sections the distance between the AEC and PEC and the previously defined landmarks were measured. On coronal images, the distances were calculated from the thickness of the cross-section and the number of sections between the various structures. RESULTS: The AEC was identified as a separate canal in 84% of patients, and was embedded in the ethmoid roof in 16%. The PEC was seen as a separate canal in 8% and was present in the ethmoid roof in 92%. On the 1 mm thick coronal and transverse sections, a third canal was identified at the junction of the middle and posterior third of the AEC-PEC distance in both of the images. The average lengths of these canals were 4-12 mm (mean 8.2 mm) for the AEC, and 2-13 mm (mean 7.6 mm) for the PEC. CONCLUSIONS: To avoid the complications that can develop during endoscopic sinus surgery; the course, length and the angulations of the anterior and posterior ethmoidal arteries and their canals can be identified by CT in standard positions if a sufficiently thin section thickness is used. The present study has shown the exact CT localization of the AECs and PECS, which are frequently overlooked when evaluating para-nasal sinuses.

Implantation of novel small-diameter polyurethane vascular prostheses interposed in canine femoral and carotid arteries.

OBJECTIVES: The performance of small-diameter (3-5-mm) vascular grafts still poses a challenge in the field of vascular surgery. We present here our preliminary experience with implanting unique small-sized polycarbonate urethane vascular grafts in 7 dogs. MATERIAL AND METHODS: Each animal was implanted with 4 interposition grafts, 2 femoral and 2 carotid. No anti-thrombotic medication was administered. Doppler sonography was performed at 3-month intervals to examine for patency and flow characteristics. Animals were sacrificed electively at 3, 6 and 12 months. RESULTS: At 3 months, all grafts were patent. After 6 months, 3 grafts occluded and at 1 year a further 6 grafts occluded. Hence 9 of 28 grafts occluded (67.9% patency). During the study, no correlation could be established between flow velocity or resistance index and occlusion. Histopathology showed intimal hyperplasia to be the cause of occlusion. CONCLUSIONS: Compared to literature data on small-diameter grafts in the same position, ADIAM's Biomechanical grafts performed clearly better. Compliance data suggest a correlation between elastic compliance and patency.

Beneficial effects of iloprost during experimentally induced hemorrhagic shock.

BACKGROUND: The aim of the study was to evaluate the efficacy of iloprost on myocardial insufficiency associated with hypovolemic shock in dogs. We designed the study as a controlled randomized study. METHODS: Sixteen mixed-breed dogs were included into the study and divided into two equal groups as the control and iloprost groups. Mean arterial pressure was reduced to 45 mmHg by withdrawing the arterial blood into citrated bags. The control group did not receive any drug but the other group received iloprost at a rate of 20 ng/kg/min by an infusion pump. Iloprost infusion was started 30 min after the blood pressure was reduced to 45 mmHg. All measurements were made before removal of blood, 45 min after exsanguination and at 1 hour intervals for 3 hours. Left ventricular stroke work index was measured 72 hours after the study. The hemodynamic and biochemical parameters and blood gas analysis were obtained. RESULTS: After hemorrhage, cardiac index (CI) decreased significantly from 132 +/- 14 to 51 +/- 8 ml/kg/min in the control group and from 128 +/- 11 ml/kg/min to 47 +/- 13 ml/kg/min in the iloprost group, respectively but at the end of the third hour it was 81 +/- 8 ml/kg/min in the control group and 105 +/- 6 ml/kg/min in the iloprost group (p < 0.05). Tumor necrosis factor-alpha (TNF alpha) was 41 +/- 8 pg/ml in the control group and 18 +/- 6 in the iloprost group 3 hours after bleeding (p < 0.05). Tumor necrosis factor-alpha concentration was significantly higher in the control group than in the iloprost group. There was no significant difference in pH between the groups but actual bicarbonate concentrations were different between the groups (p < 0.05). At the end of the third hour total body oxygen consumption was 105 +/- 11 ml/min in the control group and 132 +/- 12 ml/min in the iloprost group (p < 0.05). Oxygen delivery 3 hours after hemorrhage was 201 +/- 19 ml/min in the control group and 252 +/- 24 ml/min in the iloprost group (p > 0.05). Left ventricular stroke work index was higher in the iloprost group (p < 0.05). CONCLUSIONS: Hemorrhagic shock causes tumor necrosis factor-alpha release which may lead to multiple organ failure. Organ dysfunction still persists even after the appropriate treatment. Iloprost attenuates the release of tumor necrosis factor-alpha which may improve the adverse effects of hemorrhagic shock.

Prevention of intimal hyperplasia by single-dose pre-insertion external radiation in canine-vein interposition grafts.

OBJECTIVES: to evaluate the efficacy of single-dose pre-insertion gamma radiation of vein grafts in the prevention of intimal hyperplasia. METHODS: femoral artery interposition grafts with internal jugular vein were inserted in 12 mongrel dogs. The animals were randomly divided into two groups. Immediately before graft replacement, jugular veins were treated with a single dose of cobalt-60 radiation at 14 Gy or received no radiation (control group). Six weeks after graft insertion, the vein grafts were pressure-perfusion fixed and harvested for the histomorphometric analysis. Quantitative data on anastomotic stenosis were calculated from Gilman parameters after cross-sectional image analysis. RESULTS: vein grafts treated with radiation demonstrated significantly decreased neointima formation compared with grafts in the control group. The mean Gilman parameter for the control group was 1.09 S.E.M. 0.34 mm and for the radiotherapy group was 0.65 S.E. M. 0.23 mm (p<0.05). All vein grafts in the radiotherapy group had a decreased amount of intimal and cellular infiltration. CONCLUSION: single-dose external pre-insertion gamma radiation of vein grafts reduced the amount of intimal hyperplasia in this animal model.

Reduction of the infarcted area with the use of simplified coronary sinus retroperfusion during experimental coronary artery occlusion.

This study examined if the use of simplified coronary sinus retroperfusion would lead to any reduction in the infarcted area associated with improved right and left ventricular function. Twelve mongrel dogs were entered in this study. Following anesthesia, a fast response thermistor was placed on the pulmonary artery via the jugular vein and aorta via the left ventricular apex. The left anterior descending artery (LAD) was separated from the vein. A retrograde cardioplegia catheter was inserted into the coronary sinus. Following these procedures, LAD was occluded for a period of 3.5 h. After 30 min ischemia, the aorta-coronary sinus connection was established. The animals were divided into two equal groups. One group was not treated and was considered the control group (six animals). In the remaining group (six animals), retroperfusion was used and was considered the retroperfusion group. At the end of the study, the left ventricular ejection fraction was 65+/-15% in the retroperfusion group and 48+/-5% in the control group (P<0.05). The left ventricular stroke work index was 0.44+/-0.04 (g m/kg) in the retroperfusion group and 0.31+/-0.05 (g m/kg) in the control group (P<0.05). Cardiac output was 1650+/-75 ml/min in the retroperfusion group and 1250+/-125 ml/min in the control group. The ratio of the infarct size to the area at risk was 49+/-5% in the control group and 7+/-3% in the retroperfusion group. In light of these studies, we conclude that simplified coronary sinus retroperfusion appears to be an effective method that must be taken into consideration.