Anatomic variations of the deltoid muscle insertion: a cadaveric study

Background

The deltoid is a trisegmented muscle with anterior, middle, and posterior components. While the clinical relevance of the presence of anatomic variations of the deltoid origin and insertion continues to be debated, the architecture of the deltoid muscle is more complex than initially believed. This study aimed to evaluate the gross anatomy of the deltoid muscle insertion by qualitatively and quantitatively characterizing the insertion and location of the deltoid muscle's anterior, middle, and posterior components. This information is valuable to surgeons as it raises awareness of potential variants that could be encountered during surgery, promotes mindfulness of neurovascular proximities, and reduces the likelihood of confusion between adjacent muscle fibers.

Methods

Eight nonpaired, fresh-frozen clavicle-to-fingertip cadaveric shoulders were acquired for the study (6 left, 2 right). The average age of the cadavers was 79.5 years (range: 64-92). The standard deltopectoral approach was carried out on all specimens. The planes dividing the anterior, middle, and posterior deltoid were identified and marked. Once complete exposure had been achieved, digital calipers were used to record the size of the deltoid insertion. The specimens were qualitatively assessed to characterize the style of insertion they demonstrated.

Results

The average length of the deltoid insertion was 39.45 ± 9.33 mm (n = 8). Six of the eight shoulders demonstrated an insertion style previously characterized in the literature. The remaining two shoulders highlighted an insertion pattern not previously described.

Conclusion

The current study demonstrates a novel insertion pattern for the deltoid muscle that has not been previously characterized. This "step-off" insertion pattern shows that the anterior, middle, and posterior tendons are inserted superior-medial, directly on, and inferior-lateral to the deltoid tuberosity and was found in 2/8 of our cadaveric specimens.

Mesenteric sparing approach for advanced nodal extent in small intestinal neuroendocrine tumors. Is there a limit to the vascular resection in order to avoid creating a short small bowel syndrome? An anatomic research study

PURPOSE

By selectively perfusing the first three jejunal arteries (JA), we aim to assess the individual perfusion length of small bowel (SB) and its impact on nodal resection in stage III-up small-intestinal neuroendocrine tumors (SI-NET).

METHODS

Our anatomical research protocol implies a midline laparotomy and three measures of the SB length. We then perform a classical anterior approach of the superior mesenteric vessels. We carry on with the complete dissection and checking of the superior mesenteric artery (SMA) in order to identify the first three JA. Then we selectively perfuse each artery with colored latex solutions and measure the length of small bowel perfused respectively.

RESULTS

We conducted our protocol on six cadaveric subjects. Mean(SD) SB length was 413(5.7), 535(13.2), 485(15), 353(25.1), 730(17.3) and 525(16° cm respectively from subject one to six. Most JA originated from the left side of the SMA. The first JA originated from its posterior wall in two subjects. Mean(SD) distance of origin of the first three JA was 4.6(1.3)cm, 6(1.1)cm and 7.1(0.9)cm respectively. Mean(SD) diameter of SMA was 10.8(3.3)mm. Mean diameter of the three first JA was 4(1.4)mm, 4(1.5)mm and 5(1.2)mm respectively. Mean(SD) SB length perfused by first and second JA was 224(14.9)cm, 175(8.6)cm, 238.3(7.6)cm, 84.3(5.1)cm, 233.3(5.8)cm and 218.3(10.4)cm respectively from subject one to six.

CONCLUSION

We observed a trend suggesting that the first and second JA may sustain a SB length beyond the viable 1.5 m limit, implying the feasibility of stage III-up SI-NET resection with just two JA.

Risk factors for diaphragmatic injury in subxiphoid video-assisted thoracoscopic surgery

BACKGROUND

Subxiphoid video-assisted thoracoscopic surgery (VATS) is considered a safe and feasible operation for anterior mediastinal mass resection. However, diaphragmatic injury, presented as tearing or puncturing, may occur during subxiphoid VATS despite of low incidence. This study aims to explore risk factors for diaphragmatic injury in subxiphoid VATS, as well as strategies to reduce occurrence of the injury.

METHODS

We retrospectively reviewed clinical records of 44 consecutive adult patients who underwent subxiphoid VATS. These patients were divided into two groups: diaphragmatic injury group and non-injury group. Perioperative outcomes and anatomic features derived from 3D CT reconstructions were compared between the two groups.

RESULTS

Significant differences were observed in operation time (223.25 ± 92.57 vs. 136.28 ± 53.05, P = 0.006), xiphoid length (6.47 ± 0.85 vs. 4.79 ± 1.04, P = 0.001) and length of the xiphoid below the attachment point on the diaphragm (24.86 ± 12.02 vs. 14.61 ± 9.25, P = 0.029). Odds ratio for the length of the xiphoid below the attachment point on the diaphragm was 1.09 (1.001-1.186), P = 0.048 by binary logistic regression analysis.

CONCLUSIONS

We identified the length of the xiphoid below the attachment point on the diaphragm as an independent risk factor for diaphragm injury during subxiphoid VATS. Prior to subxiphoid VATS, a 3D chest CT reconstruction is recommended to assess the patients' anatomic variations within the xiphoid process. For patients with longer xiphoid process, a higher incision at the middle and upper part of the xiphoid process, and partial xiphoid process resection or xiphoidectomy is preferred.

Superior mesenteric artery revisited using magnetic resonance angiography

PURPOSE

We aimed to examine the superior mesenteric artery in detail by magnetic resonance angiography to provide an alternative to other imaging methods, to reduce the exposure time of patients and physicians to X-rays and the time spent in catheter angiography, to determine the variations, positions, and locations of the celiac trunk, and to provide detailed information for surgeons and interventional radiologists using this method.

METHODS

The procedures were approved by the Kocaeli University Medical School Non-Interventional Clinical Research Ethics Committee (10.04.2023, approval number: 2021/51). MR angiography images of 185 patients with abdominal imaging in PACS (Picture Archiving Communication Systems) were retrospectively registered. The level of origin of the superior mesenteric artery according to the vertebral column, angle of origin, distance between the superior mesenteric artery and branches of the abdominal aorta, and branching pattern of the superior mesenteric artery were evaluated. Parameters were evaluated according to gender and age using SPSS version 25.

RESULTS

The distance between superior mesenteric artery-inferior mesenteric artery and superior mesenteric artery-aortic bifurcation in males was higher than in females, and the difference was statistically significant. In females and the whole study group, a low, positive and significant relationship was found between age and superior mesenteric artery-sagittal angle. The most common origin site for the superior mesenteric artery, according to the vertebral column was found to be at L1 middle for males and L1 upper for females. The most common superior mesenteric artery branching pattern was classical type in both genders.

CONCLUSION

Individual evaluation of the superior mesenteric artery could reduce the risks during surgical interventions, considering the relationship of the superior mesenteric artery, especially with distally located vessels, and the gender differences for the angle of origin. Furthermore, considering that interventional radiologists choose the catheter according to the angle of origin of the artery during catheter angiography procedures, individual evaluation of patients taking into account gender and age is of utmost importance.

Radiological Evaluation of Distal Tibiofibular Joint Anatomy Variations in Patients with and Without Syndesmotic Injury

Introduction

Syndesmosis injuries are a common and debilitating problem affecting the ankle joint, but the precise causes of these injuries remain unclear. In the current retrospective study, it was aimed to investigate the relationship between variations in the distal tibiofibular syndesmosis and surgically proven syndesmosis injuries.

Patients and Method

A total of 57 patients with surgically proven syndesmosis injuries and 51 patients without syndesmosis injuries were included as the control group. Computed tomography (CT) scans were used to measure six anatomical features 1 cm proximal to the tibiotalar joint, including the anterior facet length (a), posterior facet length (b), angle between the anterior and posterior facets (c), fibular incisura depth (d), tibia thickness (e), and fibula thickness (f).

Results

Comparing the measurements of the patients with and without syndesmosis injury, it was demonstrated that the anterior facet length (a) (p = 0.022) was shorter and the a-b difference (anterior facet length-posterior facet length difference) (p = 0.010) tended toward negative values. Pearson correlation analysis demonstrated that a (r = - 0.211, p < 0.033) and a-b (r = - 0.254, p = 0.010) measurements were strongly negatively correlated with syndesmosis injury.

Discussion

Our study findings suggest that the shortness of the anterior facet and the difference in length are related to syndesmosis injuries. To the best of our knowledge, this is the first study to report this relationship with syndesmosis. This study sheds light on the underlying mechanisms of syndesmosis injury, which could help clinicians in the diagnosis, treatment, and prevention of this common ankle injury.Level of evidence: Level 4: case-control study.

Anatomical variations in living donors for liver transplantation-prevalence and relationship

PURPOSE

Living donor liver transplantation (LDLT) is a widely accepted option to address the lack of a deceased liver program for transplantation. Understanding vascular and biliary anatomy and their variants is crucial for successful and safe graft harvesting. Anatomic variations are common, particularly in the right hepatic lobe. To provide evidence for screening potential liver transplant donors, the presence of vascular and biliary anatomic variations in Pakistan's preoperative assessment of transplantation donor candidates was explored.

METHODS

This retrospective cross-sectional study evaluated the hepatic artery, portal vein, hepatic vein, and biliary variations in living liver donors. The study included 400 living liver donors; data were collected from March 2019 to March 2023. We used a CT scan and MRCP to assess the anatomical variations.

RESULTS

The study examined 400 liver donors aged 18 to 53 years. Conventional arterial anatomy was the most common (65.8%), followed by replaced right hepatic artery (16%) and replaced left hepatic artery (10.8%). Conventional type 1 biliary anatomy was seen in 65.8% of cases. The dominant right hepatic vein was found in 13.3% of donors. There was a significant association between the prevalence of variant portal venous anatomy with variant biliary anatomy.

CONCLUSION

Variations of the hepatic arterial, portal venous, and biliary systems are frequent and should be carefully evaluated while selecting a suitable living donor. A strong relationship between variant portal venous and biliary anatomy was found. These findings can aid in selecting suitable candidates and improving surgical planning for liver transplantation.

Anatomy, embryology, and imaging of situs ambiguous with polysplenia and left IVC

The situs ambiguous or heterotaxy syndrome is a type of syndrome that involves multiple visceral abnormalities, vascular ones and associated with left isomerism. Malformation of gastroenterologic system includes polysplenia (segmented spleen or multiple splenules), agenesis (partial or complete) of the dorsal pancreas and anomalous of the inferior vena cava implantation. Here, we describe and show the anatomy of a patient with left side inferior vena cava, situs ambiguous (complete common mesentery), polysplenia, and short pancreas. We also discuss about the embryologic process and the implications of these anomalies during gynecologic, digestive, and liver surgeries.

Multidetector CT of the Nasal Cavity and Paranasal Sinuses Variations in 73 Patients

Detailed knowledge of the anatomy of the nasal cavity and paranasal sinuses is very important in the diagnosis of pathological processes, planning of endoscopic surgery, and radiologic guiding techniques during certain operations. Observational study. Clinic of Neurosurgery, Institute and Department of Anatomy and Pathology, Clinic and Department for Otorhinolaryngology and Maxillofacial Surgery, Faculty of Medicine. Two heads with brains were serially cut in the axial and coronal planes. 73 individuals, who were enrolled among 1848 patients, underwent examination by multidetector computerized tomography. A nasal septal deviation was seen in 65.8%, and septal pneumatization in 11%. Superior concha pneumatization was observed in 1.4% of patients, middle concha bullosa in 30.2%, and its hypoplasia in 1.4%. The lamina papyracea dehiscence was also present in 1.4%. The uncinate process was absent in 1.4%, and it was pneumatized in 4.2%. Agger nasi cells were noticed in 34.3%, and Haller and Onodi cells in 20.7% each. The olfactory fossa was shallow in 9.7%, deep in 31.6%, and very deep in 58.9%. Absence of the frontal sinus was seen in 9.7%. The presellar type of the sphenoidal sinus was present in 11%, the sellar in 35.7%, and the postsellar in 53.5%. Hypoplasia of the maxillary sinus was revealed in 1.4%, and hyperpneumatization in 4.2%. The sinus floor was usually below the level (60.3%), at the same level (20.7%), or above the level of the nasal floor (19.2%). The bony septum within the sinus was seen in 52.1%. The presented data are of a great significance in order to avoid a misdiagnosis of the anatomic variations, to make a proper diagnosis of certain diseases, and for safe endonasal operations.

The Anatomic Variations of the Nose and Paranasal Sinuses and Their Effect on Chronic Rhinosinusitis in Adult Patients

To find out the anatomic variations of nose/paranasal sinuses and how they affect the sinuses in chronic rhinosinusitis (CRS). This observational cross-sectional study included adults with CRS, refractory to optimum medical management, planned for functional endoscopic sinus surgery (FESS). Pre-operative naso-endoscopy and computed tomography (CT) were utilized to estimate the extent of CRS, and to note the anatomic variations of the sinuses. The findings were corroborated within the practical scope of FESS. The anatomic variations were evaluated to establish how they affected the related sinus(es). Most of the 53 patients were young adults presenting with nasal obstruction (77%), discharge (76%) and headache (68%). On diagnostic naso-endoscopy, prominent agger bulge (83% of the nasal sides), prominent uncinate (18%), inferior turbinate hypertrophy (34%), concha bullosa (38%), mucopus and polyp in the middle meatus (51%, 19%; respectively), and gross septal deviation (55%) were noted. The spheno-ethmoid and frontal recesses were predominantly unremarkable. CT revealed inferior turbinate hypertrophy (38% of the nasal sides), agger (100%), and lateralized/collapsed uncinate (8%). Ethmoids and maxillary sinuses were diseased in 50% and 65% respectively, with blocked ostiomeatal complex in 32% and prominent bulla in 48%. Frontal and sphenoid sinuses were least involved (10%, 2%; respectively). Enlarged agger caused maxillary sinusitis (87%), whereas anterior ethmoiditis resulted from enlarged agger (100%), bulla (89%) and frontal cells (51%). Identification of the anatomic variations of the nose/paranasal sinuses through CT and naso-endoscopy (diagnostic, per-operative) is crucial to understand the pattern, extent and severity of the involvement of sinuses in CRS.

Replaced right hepatic artery arising from the distal renal artery, a new variation

PURPOSE

Arterial irrigation of the liver is highly variable and widely studied due to its importance in the correct planification of the surgical or endovascular treatment of the hepatobilary area. Various classifications have been published of the common and uncommon anatomic variations of the hepatic arterial distribution. While the classic anatomic pattern of the proper hepatic artery-when it originates from the celiac trunk dividing into left and right branches-represents 50-83% of the described patterns, there are numerous uncommon distributions based on the presence of replaced or accessory hepatic arteries. In this article, we present a case of a replaced right hepatic artery originating from the right distal renal artery.

METHODS

Contrast enhanced computed tomography (CECT) examination was performed on a 67 years-old male patient with compensated alcoholic cirrhosis as part of the disease monitoring.

RESULTS

The replaced right hepatic artery of the patient arises from the right distal renal artery and-after its cranial course-enters the porta hepatis posterior to the main portal vein. After giving off the cystic artery, it irrigates the right hepatic lobe. The left hepatic artery does not show any variation.

CONCLUSION

We present CT angiography images of an extremely rare anatomic variation of the hepatic arterial irrigation in a cirrhotic patient.

Persistent trigeminal artery associated with an occipital arteriovenous malformation: a case report and literature review

BACKGROUND

Persistent trigeminal artery or persistent primitive trigeminal artery (PTA) is the most common carotid-basilar anastomosis in both cadaveric and live patient studies, followed by persistent hypoglossal and persistent otic arteries. Approximately 0.2% of all angiographies reported this finding.

CASE REPORT

We present the case of a 21-year-old male who arrived at the emergency department with tonic‒clonic seizures. After performing diagnostic contrast magnetic resonance imaging and digital subtraction angiography, the patient was diagnosed with a right occipital arteriovenous malformations (AVM) fed by the right calcarine artery associated with an ipsilateral PTA. After considering surgical and endovascular treatment options, the patient was selected for watchful waiting. We included a literature review of the PTA, the results of a PubMed search regarding the combined presence of these findings, and a brief discussion providing insight into the implications for treatment.

CONCLUSIONS

Although several studies have linked PTA to different vascular pathologies, such as cerebral aneurysms, the association between PTA and AVMs remains scarce. This case, along with the literature review, shows that further research is needed to characterize the relationship between these findings.

Right posterior bile duct stricture after central bisectionectomy or anterior sectionectomy

PURPOSE

Before performing anterior sectionectomy (AS) or central bisectionectomy (CBS), the anatomy of the right posterior bile duct (RPBD) must be cautiously assessed owing to the many variations of the RPBD and its variations could be related to bile duct injury.

METHODS

Clinical data of patients who underwent AS or CBS from 2009 to 2018 were reviewed. The bile duct anatomy according to Okubo's criteria and the right bile duct (RBD) length were evaluated using MRI, and we performed a risk factor analysis of the RPBD stricture (RPBDS).

RESULTS

A total of 68 patients were included. Type A bile ducts were the most common (n = 36, 52.9%). Five (7.2%) patients had RPBDS requiring intervention. RPBDS only occurred in patients with a type A bile duct and a type A portal vein undergoing surgery using the Glissonian sheath approach. Moreover, when the RBD length was > 12 mm, the sensitivity and specificity were 0.8 and 0.889, respectively. In multivariate analysis, RBD length of > 12 mm was significant.

CONCLUSION

A careful review of RPBD anatomy especially in patient with long RBD and caution when using the anterior Glissonian sheath approach might be helpful to prevent RPBDS during AS or CBS.

The middle glenohumeral ligament: a classification based on arthroscopic evaluation

BACKGROUND

Although middle glenohumeral ligament (MGHL) variations have been shown in the literature, their clinical effect and relationship with intra-articular pathologies have yet to be revealed, except for the Buford complex. This study was designed to classify MGHL and to reveal its relationship with clinical pathologies.

METHODS

A total of 843 consecutive shoulder arthroscopies were evaluated retrospectively, and a classification system was proposed for MGHL with regard to its structure and its relation to the anterior labrum. The associations of each MGHL type with superior labrum anterior-posterior (SLAP) lesions, subscapularis tears, and anterior instability were investigated.

RESULTS

MGHL variations were grouped into 6 types according to the classification. A significant difference in favor of type 6 MGHL (Buford complex) was observed in the distribution of SLAP lesions (P < .001). There was no significant difference between MGHL types and the distribution of anterior instability history (P = .131) and subscapularis tears (P = .324).

CONCLUSION

SLAP lesions accompany type 6 MGHLs (Buford complex) significantly more frequently than other types. There is also a negative relation between the anterior instability and thicker MGHL variants.

Anterior Cerebral Artery and Anterior Communicating Artery Variations: Assessment with Magnetic Resonance Angiography

BACKGROUND

Although anterior cerebral artery (ACA) and anterior communicating artery (AcomA) variations have been frequently investigated by contrast-enhanced angiography, the number of studies performed with magnetic resonance angiography is quite low. Our aim in this study is to investigate ACA and AcomA variations with time of flight magnetic resonance angiography (TOF MRA).

METHODS

Source and maximum intensity projection images of 581 adult patients (273 males, 308 females) who were scanned for intracranial arteries with the TOF MRA method were retrospectively analyzed.

RESULTS

We found the typical configuration rate of the ACA and AcomA complex to be 40.6%. The most common structural anatomic variations out of typical configuration were AcomA aplasia (18.9%) and AcomA hypoplasia (17.9%), respectively. The least frequent variation that we found was duplicated AcomA (0.9%). When we examined gender comparatively, unilateral A1 segment aplasia was found to be higher in males and azygos ACA was found to be higher in females (P = 0.001 and P = 0.029, respectively).

CONCLUSIONS

In this study, in which we used the TOF MRA technique, we detected high rates of anatomic variations of ACA and AcomA. This method, which is noninvasive, does not require contrast material and does not contain ionizing radiation, can be preferred especially in the evaluation of patients with kidney disease and contrast allergy.

Anatomy of the Dorsal Meningeal Artery Including Its Variations: Application to Skull Base Surgery and Diagnostic and Interventional Imaging

BACKGROUND

The blood supply to the skull base is important to surgeons and those performing interventional and diagnostic procedures in this region. However, 1 vessel with a vast distribution in this area, the dorsal meningeal artery (DMA), has had few anatomic studies performed to investigate not only its normal anatomy but also its variations. Therefore the current study aimed to analyze the DMA via cadaveric dissection.

METHODS

In 10 adults, latex-injected, cadaveric heads (20 sides), the DMA was dissected using a surgical microscope. This artery and its branches were documented and measured.

RESULTS

A DMA was identified on all sides. In the majority (85%), it was a branch of the meningohypophysial trunk or common stem with either the inferior hypophysial or tentorial arteries and always had branches that traversed the basilar venous plexus. Multiple branches of the DMA were identified and categorized as bony, dural, neural, and vascular.

CONCLUSIONS

Surgeons operating at the skull base or clinicians interpreting imaging of this area should have a good working knowledge of the DMA and its typical and variant anatomy.

Cone Beam CT Evaluation of Maxillary Sinus Floor and Alveolar Crest Anatomy for the Safe Placement of Implants

BACKGROUND

Alveolar bone height in the posterior maxillary region is very important and critical for dental implant planning and placement.

OBJECTIVES

This study aimed to evaluate the anatomy of the maxillary sinus floor in relation to the alveolar crest and to determine variations in the vertical measurements between the maxillary sinus floor and the alveolar bone crest tip in the posterior edentulous maxilla with the use of cone beam computerized tomography.

METHODS

This analysis enrolled 234 retrospectively selected patients (123 males with mean age 52.95±11.74 (range 32-76 years) and 111 females with mean age 58.14±11.92 (range 32-75 years)) with edentulous posterior maxillary regions. The maxillary sinus floor was divided into three anatomical segments (anterior, median and posterior) in relation to the transverse palatine suture. The measurements were performed on 3D surface rendered volumetric images by using rotation and translation of the views. Landmarks for measurement were specified by using a cursor driven pointer. Vertical lines were marked on the cross-sectional images between the alveolar ridge and the deepest point of the maxillary sinus floor for each of the three regions. P < 0.05 was regarded as statistically significant.

RESULTS

The mean distance values between the sinus floor and the alveolar crest in the anterior, median and posterior regions were 8.74±3.97 mm, 5.37±3.23 mm and 7.06±3.28 mm, respectively. Measurements in the anterior region were found to be high in both total and gender groups compared to other regions. Also, subsinus alveolar bone heights decreased with increasing age in both genders in all three regions.

CONCLUSION

This study emphasizes that the mean subsinus alveolar bone height is highest in the anterior segment of the edentulous posterior maxilla. These results may guide clinicians to make the decision of implant placement area and lead to less invasive alternative surgery methods for edentulous posterior segments.

Arterial Vascular Structures Running Through Retrotransverse Foramen and Retrotransverse Groove of the Atlas Vertebrae

OBJECTIVE

Retrotransverse foramen (RTF) and retrotransverse groove (RTG) are anatomic variations of the atlas (C1) vertebrae. RTF contains an anastomotic vein connecting atlanto-occipital and atlanto-axodian venous sinuses. The purpose of this study was to analyze the arterial vascular structures running though the RTF and RTG.

METHODS

Three-dimensional volume rendered computed tomography angiography (3D VR CTA) images of 427 patients (264 men, 163 women; age 17-87 years) were reviewed and evaluated using the RadiAnt DICOM Viewer (version 5.0.2; Medixant, Poznan, Poland). The incidence of RTF or RTG, the incidence of the V3 segment of vertebral artery variants, and the artery vascular structures inside the RTF and RTG anatomic variation of C1 were analyzed.

RESULTS

Fifty (11.7%) atlases presented RTF anatomical variant; 113 (26.5%) atlases presented RTG anatomical variants. The incidence of the V3 segment of vertebral artery variants was 0.94% (4 of 427). Three (0.7%) were persistent first intersegmental artery and 1 (0.2%) was the fenestration of the vertebral artery on left side. In 4 cases of C1 vertebral artery V3 segmental variants, there were no RTF and RTG. No artery vascular structure was found in RTF or RTG.

CONCLUSIONS

The RTF or RTG of C1 was a common anatomical variant. No arterial vascular structure runs though the RTF or RTG. The presence of C1 RTF and RTG variants had no effect on the V3 segmental course of the vertebral artery. Preoperative understanding of these variations using 3D CTA are helpful for the safe execution of the upper cervical posterior approach surgeries.

Anatomical Variations of the Vertebral Artery: Analysis by Three-Dimensional Computed Tomography Angiography in Chinese Population

OBJECTIVE

To analyze the anatomical variations of V3 and V2 segments of the vertebral artery in the Chinese population.

METHODS

The current retrospective study was an observational, anatomical, radiological research. Between 1 January 2018 to 31 December 2019, the data of 589 continuous head-and-neck three-dimensional computed tomography angiography were observed and analyzed using the open-source software of Horos. There were 415 males and 174 females with an average age of 44.63 ± 2.5(18-74) years. The variations of the V3 segment were defined as persistent first intersegmental artery (PFIA) and paracondylar processes (PP). The variations of V2 segments were unusual vertebral artery entrance transverse foreman (UE-V2S) and midline migration (MM). The incidences of all variations were summarized and the gender, side characters were compared.

RESULTS

Among the patients, 4.34% (18/415) males and 4.60% (8/174) females were with the variation of PFIA. Meanwhile, 12.29% (51/415) males and 10.92% (19/174) females were with the variation of PP. Then 18.80% (78/415) males and 16.67% (29/174) females were with UE-V2S. All the variations above were not different in genders. As for the variation of MM, 3.86% (16/415) males and 8.62% (15/174) females were identified, and the difference of genders was significant for this type of variation (P < 0.05). The differences between each side were also observed and analyzed for all variations and no differences were found.

CONCLUSION

There are several variations of V3 and V2 segments of the vertebral artery are associated with the cervical surgeries, most were without differences in genders and sides, except the variation of MM.

Gluteoperinealis muscle: a surgically important variation

BACKGROUND

Anatomical variations are common in gluteal region. This report presents two cases of gluteoperinealis muscles detected during radiological imaging.

CASE PRESENTATION

Our study was conducted on two patients. This report describes an accessory muscle detected in the gluteal region on MRI examination of a patient who admitted to our clinic after a firearm injury and a second patient examined with CT imaging who had signs of pelvic infection. In the first case, this accessory muscle originated bilaterally from the fascia of the gluteus maximus throughout its posteromedial side and was attached to the perineal body. In the second case, it extended forward from the fascia of the gluteus maximus muscle and inserted to the cavernous body of penis on the left side and to the perineal body on the right. In the literature, this accessory muscle has been described as the gluteoperinealis muscle being a rare variation.

CONCLUSION

Considering the origin and insertion of the muscle, this variation may be important during the surgical operations of the gluteal and perineal regions.

Retroesophageal right subclavian artery associated with a bicarotid trunk and an ectopic origin of vertebral arteries

A rare branching pattern of the aortic arch in a female cadaver is reported. An aberrant right subclavian artery originated from the distal part of the aortic arch and following a retroesophageal course was recognized. Next to it, from the left to the right, the left subclavian artery and a short bicarotid trunk originating the left and the right common carotid artery were recognized. An unusual origin of the vertebral arteries was also identified. The left vertebral artery originated directly from the aortic arch, whereas the right vertebral artery originated directly from the right common carotid artery. Retroesophageal right subclavian artery associated with a bicarotid trunk and ectopic origin of vertebral arteries represents an exceptional and noteworthy case.

Two novel hepatic arterial variations in a living liver donor detected by multidetector computed tomography angiography

PURPOSE

Considering that the knowledge of variations in the hepatic vascular structure is essential for hepatic surgery and liver transplantation, we aimed to present a rare case of the anatomic variation of arterial blood supply to the liver to help prevent complications and choose suitable donors.

METHODS

We present a novel variant in this case report (living liver donor), an accessory right hepatic artery (supplying segment 6) originating from the dorsal pancreatic artery and a middle hepatic artery (supplying segment 4) arising from the pancreaticoduodenal artery (first branch of the gastroduodenal artery). Preoperative diagnosis was made using computed tomography angiography (CTA) with multiplanar reformate (MPR) images, curved planar reformate (CPR), maximum intensity projection (MIP) images and three-dimensional volume renderings (3D VR).

RESULTS

To the best of our knowledge, this is the first case in the English literature describing this type of variation. A search for new donors began since the living liver donor was not suitable due to the very thin segment 4 artery, posing potential risks for the donor and the thin segment 6 artery being a complicating factor for anastomosis.

CONCLUSIONS

The preoperative knowledge of liver blood supply has great importance in planning surgery and transplantation. CTA, reformate and reconstruction techniques allow for the evaluation of difficult and complex anatomic variations.

A case of Right Hepatic Artery anterior to the common hepatic duct: A not so rare variation

•

Anatomical variations in the RHA may concern its number, origin or route.

•

A prebiliary course of the RHA has been described with a prevalence ranging from 15 to 25%.

•

CT Angiography is the exam of choice to establish a complete vascular mapping.

•

The RHA remains an essential anatomical landmark that all surgeons must keep in mind in order to avoid any unfortunate incidents.

Introduction and importance

The hepatic arteries may be subject to anatomical variations that can cause operating difficulties with a risk of iatrogenic vascular injuries. A perfect knowledge of anatomy is an essential prerequisite for both surgeons and interventional radiologists.

Case presentation

During a duodenopancreatectomy for a pancreatic head tumor in a 46-year-old man, we observed an anatomical variation regarding the course of the right hepatic artery (RHA). Indeed, RHA arose from the proper hepatic artery (PHA) at the left edge of the hepatoduodenal ligament and instead of crossing the common hepatic duct (CHD) posteriorly which is the usual course, it passed overhead before ascending and finishing its course in the liver hilum.

Clinical discussion

Anatomical variations of the hepatic arteries can be explained by the partial or complete persistence of the fetal model. Variations in the RHA may concern its number, origin or route. A prebiliary course of the RHA has been described with a prevalence ranging from 15 to 25% depending on series. The high sensitivity of Multidetector Computed Tomographic Angiography (MCTA) allows performing a complete vascular mapping, which remains essential before any Hepato-Pancreato-Biliary (HPB) surgery.

Conclusion

This case confirms once again the frequency of anatomical variations of the hepatic arteries, and underlines the value of CT Angiography to detect them in order to best plan any HPB surgery, where RHA remains an essential anatomical landmark that all surgeons must keep in mind in order to avoid any unfortunate incidents.

Multidisciplinary Approach for the Management of Mandibular Canines with Rare Configuration

It is very rare (2%–6% cases) for a mandibular canine to have two root canals and the incidence of finding two roots with two root canals in a mandibular canine that too bilaterally is almost negligible. This case report discusses the presence and multidisciplinary management of such rarest configuration in both mandibular canines of a female patient. This case shows the importance of recognition of anatomical variations in successful accomplishment of root canal treatment.

Assessment of posterior urethra in benign prostatic hyperplasia and after its surgery

Introduction:

Surgical management of benign prostatic hyperplasia (BPH) primarily consists of transurethral resection of the prostate (TURP). Due to BPH and after surgical intervention, anatomic variations in the posterior urethra are expected. Due to the paucity of information regarding posterior urethral anatomic variations in these conditions and its aftermath, this study was undertaken to evaluate the anatomic variations in the posterior urethra after TURP.

Materials and Methods:

This prospective observational study was conducted over 2 years at the Department of Surgery and Radiodiagnosis, University College of Medical Sciences, Delhi. All consenting patients undergoing TURP for BPH were included in the study. We assessed the posterior urethral changes in BPH before and 3 months after the procedure. Diagnostic modalities used were urethrocystoscopy, micturating cystourethrogram, and retrograde urethrogram. Furthermore, the prostate volume and postvoid residual volume of urine were compared before and after its surgery using ultrasonography. Urodynamic studies were used to calculate total voided volume (TVV), peak flow rate (PFR), voiding time (VT), and hesitancy.

Results:

Mean age of the patients was 68.12 ± 7.83 years. Lengthening in posterior urethra was seen in BPH patients with a mean of 4.24 ± 1.012 cm. Postprocedure, there was a mean reduction of 2.6 ± 1.225 cm in length of the posterior urethra (P < 0.0001). Prostatic urethral angle was increased in patients suffering from BPH, and it decreased after undergoing surgical management (P < 0.679). All patients enrolled in our study had prostatic lobes enlargement, and after surgery, this enlargement was reduced in most of the patients with 21 having no prostatic enlargement, and in four patients, bilateral lateral lobe was not completely reduced (P = 1.000). Stricture in prostatic urethra was observed in 2 out of 25 (8%) patients operated for BPH. Evaluation of various parameters of urodynamic studies revealed the net improvement in the TVV of 157.746 ± 120.999 ml, as before the procedure, this value was 176.715 ± 72.272 ml, and after surgery, it was 334.46 ± 78.588 ml (P < 0.001). VT taken by patients before surgery was 57.377 ± 16.858 s, and postprocedure, this value was 33.31 ± 8.807 s. This net reduction of 24.069 ± 14.88 s was statistically significant (P < 0.0001). PFR before the procedure was 6.177 ± 3.5067, and postprocedure, this value was 26.43 ± 7.112 ml/s with a net improvement of 20.253 ± 9.226 ml/s (P < 0.0001). Hesitancy in BPH patients before the procedure was 23.908 ± 15.521 s. Postprocedure, hesitancy decreased to a value of 6.79 ± 4.435 s with a net reduction of mean 17.115 ± 15.817 s (P < 0.002).

Conclusion:

By our findings, we conclude that BPH is associated with anatomic variations in posterior urethra such as lengthening of the length of the posterior urethra and increased posterior urethral elevation, which is measured by an increase in posterior urethral angle (PUA). Whereas post-TURP, there is a shortening of posterior urethra, decrease in PUA, decrease in prostatic volume, postvoid residual urine volume, and improvement in uroflowmetric parameters.

Double origin of the extensor hallucis longus muscle: a case report

Most of the anatomic variations of the extensor hallucis longus (EHL) muscle are related to the tendon of insertion. We show a double origin of the EHL from the medial aspect of the fibula and the lateral aspect of the tibia. A 27-year-old male with a double closed fracture of tibia and fibula showed an involuntary extension of the big toe during foot plantar flexion after surgery. A tendon fibrosis by the fixation plates could be the cause of the foot functional alteration. Interestingly, the anatomic variation described could be related to the postsurgical foot dysfunction, since when the fibrotic tissue was removed the normal extension of big toe recovered. As illustrated in this case report, knowledge of anatomic variations is very useful, particularly in the context of foot surgery.

Variations in Hook of Hamate Morphology: A Cadaveric Analysis

PURPOSE

The hook of the hamate is an anatomical structure that separates the ulnar border of the carpal tunnel from Guyon's canal and serves as a landmark for surgeons. The hook of the hamate is also subject to fracture from injury. We hypothesize that there are variations in the hook of the hamate in the general population.

METHODS

One thousand pairs of hamates (2,000 hamates) from the Hamann-Todd Collection at the Cleveland Natural History Museum were analyzed. The height of the hook of the hamate and the total height of the hamate bone were measured using digital calipers. The hook height ratio was defined as the hook height divided by the total height of the hamate. Statistical analysis was performed using unpaired Student's t test to determine differences in sex and race.

RESULTS

The mean hook height was 9.8 ± 1.4 mm (range, 2.5-15.9 mm), whereas the mean hook height ratio was 0.42 ± 0.04 (range, 0.15-0.56). There was a 3.1% (62/2,000) incidence of abnormally small hooks, which we classified as hypoplastic and aplastic. Of the hypoplastic hooks, 55% (24/44) were bilateral, whereas 44% (8/18) of the aplastic hooks were bilateral. The incidence of variation in size in the hook of the hamate was highest in white females (9.3%) and lowest in black males (1.4%).

CONCLUSIONS

Abnormalities in hook of hamate anatomy are common in the general population, especially in white females.

CLINICAL RELEVANCE

Knowledge of anatomic variation in the hook of the hamate may provide additional insight into surgeons' palpation of bony anatomy, interpretation of imaging studies, and use of the hook as a landmark during surgery.

Possible Clinical Implications of Geographic Differences in Prevalence of Double Transverse Foramen

BACKGROUND

The double transverse foramen (DBLTF) is a cervical spine anatomic variant. Current literature has presented prevalence values of DBLTF in Caucasian Mediterranean subjects that seem to be higher than those observed in other samples of subjects. Therefore we aimed to test if Caucasian Mediterranean subjects present a higher prevalence of the DBLTF than sub-Saharan African subjects.

METHODS

We analyzed the presence of DBLTF in cervical spines of 100 skeletons from Caucasian Mediterranean subjects and 91 skeletons from sub-Saharan African subjects, resulting in a total of 1337 cervical vertebrae having been studied.

RESULTS

No DBLTF was found in vertebrae C1, C2, and C3. The pattern of prevalence observed in all samples analyzed indicated the prevalence ranged from exhibiting the most to the least prevalence as C6 > C5 > C7 > C4. The sub-Saharan African subjects presented a significant reduced DBLTF prevalence of 2.2%, 14.3%, 19.8%, and 3.3% in C4 (P = 0.043), C5 (P = 0.004), C6 (P < 0.001), and C7 (P = 0.041), respectively, than that presented by Caucasian Mediterranean subjects (9.0%, 32.0%, 45.0%, 11.0% in C4, C5, C6, and C7, respectively).

CONCLUSIONS

Our study has revealed that this anatomic variation is more frequently found in Caucasian Mediterranean subjects than in sub-Saharan African subjects.

Aberrant splenic artery rising from the superior mesenteric artery: a rare but important anatomical variation

Aberrant splenic artery originating from the superior mesenteric artery (SMA) is extremely rare and recognition of this anomaly is important in the pre-operative planning of complex surgery such as pancreatic surgery, liver transplantation and vascular surgery. We present the case of an 80-year-old female diagnosed as septic shock due to mesenteric ischemia and obstructive pyelonephritis. Her splenic artery was originating from the SMA and the anomaly was readily appreciated on the pre-operative CT images. An explorative laparotomy associating extensive small bowel resection with endarterectomy of the proximal part of the SMA was performed. During intra-operative SMA control, we confirmed the aberrant splenic artery arising from SMA, and successfully avoid any arterial injury on the splenic artery with isolation and separated proximal and distal clamping. The anatomical vascular variation should be recognized in the pre-operative work-up of a determined surgical procedure to avoid potential intra-operative arterial injuries.

Rare anatomic variation of the hepatic arterial blood supply: case report and literature review

PURPOSE

Our aim is to present a rare case of anatomic variation of the arterial blood supply to the liver because preoperative knowledge of hepatic vascular variations is mandatory in hepatic surgery and liver transplantation.

METHODS

We present a case of unusual arterial blood supply to the liver, a right hepatic artery coming from the splenic artery, associated to a classical common hepatic artery and a left hepatic artery from the left gastric artery. Preoperative diagnosis was made using CT-scan and 3D reconstruction.

RESULTS

The right hepatic artery was found behind the portal vein and its diameter showed its importance in the vascularisation of the liver. To our knowledge this type of variation has only twice been described before. The accuracy of the 3D reconstruction allowed us to adopt the best surgical strategy to avoid lesions of the two accessory arteries which proved important sources of blood supply.

CONCLUSIONS

Precise preoperative evaluation of liver blood supply has great importance on surgical, transplantation strategy and outcome and rare anatomic variations have to be known to avoid lesions of potentially important arteries. New techniques of 3D reconstruction can ease the preoperative recognition of such difficult anatomic variations.

Prevalence of anatomic variations of the atlas vertebra

BACKGROUND CONTEXT

The retrotransverse foramen (RTF), arcuate foramen (AF), unclosed transverse foramen (UTF) and posterior atlas arch defects (PAAD) are anatomic variations of the atlas vertebra that surgeons must be aware of before spine surgery is performed.

PURPOSE

To analyze the prevalence of the AF, RTF, UTF, and PAAD.

STUDY DESIGN

Ex-vivo anatomical study.

PATIENT SAMPLE

Two hundred eighteen atlas vertebrae obtained from 100 Caucasian subjects and 118 sub-Saharan African subjects (48 Sotho subjects, 35 Xhosa subjects and 35 Zulu subjects).

METHODS

We studied 218 atlas vertebrae from skeletons of the Raymond A. Dart Collection in order to analyze the prevalence of AF, RTF, UTF, and PAAD in both Caucasian and sub-Saharan African subjects.

OUTCOME MEASURES

Not applicable.

RESULTS

Sixty-nine (31.2%) atlases presented anatomical variants: 64 (29.3%) presented one anatomical variant, 4 (1.8%) presented two, and 1 (0.5%) presented three. AF, RTF, UTF, Type A and Type E defects were present in 35 (16.1%), 17 (7.8%), 17 (7.8%), 5 (2.3%), and 1 (0.5%) vertebrae, respectively. The vertebrae with two anatomical variants presented a bilateral UTF and a Type A defect, a bilateral AF and a Type A defect, a right UTF and a left AF, and a right UTF and a Type E defect. The vertebra with three anatomical variants presented a bilateral RTF, a left UTF, and a left AF. No sex differences in prevalence of the RTF (p=.775), AF (p=.605), UTF (p=.408) and Type A defects (p=1.000) were found in the sub-Saharan African and Caucasian groups (RTF, p=.306; AF, p=.346; UTF, p=.121; Type A defects, p=.561). Comparison between the sub-Saharan African (all subjects) and the Caucasian group revealed no differences in the UTF (p=.105), AF (p=.144), RTF (p=.542) and Type A defects (p=.521) prevalence. Also, no differences in the prevalence of the UTF (p=.515), AF (p=.278), and RTF (p=.857) between Zulu, Xhosa and Sotho subjects were found. Neither were found sex differences in the prevalence of UTF, RTF and AF in Zulu (p=.805, p=.234, p=.129), Xhosa (p=.269, p=.181, p=.309), and Sotho subjects (p=.062, p=.590, p=.106).

CONCLUSIONS

The present study has revealed no sex differences in the prevalence of AF, UTF, RTF or PAAD in both Caucasian and sub-Saharan African subjects. This research has also indicated no differences in the prevalence of the UTF, AF and RTF between Zulu, Xhosa and Sotho subjects. In addition, this study has revealed no differences in the Type A, UTF, AF, and RTF prevalence between the sub-Saharan African (all subjects) and the Caucasian subjects. These variations may be known by surgeons before spine surgery for better planning.

Neurovascular Surgical Keys Related to Sphenoid Window: Radiologic Study of Egyptian's Sphenoid

OBJECTIVES

The anatomic variations of the sphenoid sinus and its relation to the surrounding neurovascular structures are a subject of interest. The purpose of this study was to radiologically assess the frequency of protrusion/dehiscence of key neurovascular landmarks surrounding the Egyptians' sphenoid.

METHODS

This is a cross-sectional descriptive study of sinonasal computed tomography of the sphenoid sinus in 500 adult Egyptians, conducted at Mansoura University Hospitals; Egypt, over a period of 1 year. Two archives were used for collecting the data; the hard archive and the electronic archive. Variables of interest included the extent of sphenoid sinus pneumatization; intersphenoid septation pattern; protrusion/dehiscence of the internal carotid artery, optic nerve, maxillary nerve, and vidian nerve; and detection of the Onodi cell.

RESULTS

Population of this study included 265 women and 235 men. Their ages ranged from 18-68 years. The bilateral sellar-type pneumatization was shown as the most common pneumatization type (96.8%). Pneumatizations of the pterygoid process, anterior clinoid process, and greater wing of the sphenoid were identified in 9.3%, 8.9%, and 31.8% consequently. A single intersphenoid septum was detected in 85.2%, whereas multiple intersphenoid septums were noted in 11.6%. Protrusion of the internal carotid artery, optic nerve, vidian nerve, and maxillary nerve was recorded in 8.5%, 9.1%, 6.6%, and 3.4% consequently, while dehiscence was reported in 7.2%, 15%, 11.9%, and 4.2% consequently as well. Onodi cell was recognized in 18%.

CONCLUSIONS

This radiologic study highlights significant variations of surgically important anatomic structures related to the sphenoid sinus in Egyptians.

Additional muscular slip of the flexor digitorum longus muscle to the fifth toe

Despite the fact that there are numerous reports on muscular variations in the sole of the foot, routine dissection in a formaldehyde-fixed cadaver revealed an accessory flexor digiti quinti muscle, which to the best of our knowledge is a very unusual variant. This was in the form of a slender, 38 mm long muscular slip, with a proximal and distal tendon extending from the common flexor digitorum longus tendinous plate out to the distal phalanx of the fifth toe. An associated finding was the absence of the musculotendinous portion of the flexor digitorum brevis to the same toe. A developmental explanation for this variation is presented. Clinical implications with regard to this anatomical condition may result in clawing of the fifth toe.

The Celiac Trunk and Its Anatomical Variations: A Cadaveric Study

Background

The celiac artery, celiac axis or celiac trunk is the first major abdominal branch of the aorta. Anatomic variations and accessory vessels have been reported with variable percentages. The purpose of this study was to report the pattern of the celiac trunk and its anatomic variations in a sample of Mexican population.

Methods

Celiac trunk dissection was performed in 140 fresh cadavers. Cadavers of Mexican subjects aged 18 years and older were included. Cadavers with previous upper abdominal surgery, abdominal trauma, disease process that distorted the arterial anatomy or signs of putrefaction were excluded. Celiac trunk variations and external diameter, accessory vessels, and vertebral level of origin were described. Celiac trunk patterns were reported according to the Panagouli classification. This study was reviewed and approved by the Ethics Committee of our Hospital.

Results

The celiac trunk derived in a common hepatic artery, a left gastric artery and a splenic artery (type I) in 43.6% of dissections. A true tripod was found in 7.1% and a false tripod in 36.4%. Celiac trunk bifurcation (type II) was found in 7.1%. Additional branches (type III) were observed in 47.9%. One or both phrenic arteries originated from the celiac trunk in 41.4% of dissections. Celiac trunk tetrafurcation was observed in 12.9%, pentafurcation in 12.9%, hexafurcation in 1.4%, and heptafurcation in 0.7%. The mean diameter of the celiac trunk ranged from 6 to 12 mm, with a mean diameter of 7.2 mm (SD = 1.39 mm). No significant difference was found between the diameters of the different types of celiac trunk (P > 0.05). The celiac trunk originated between the 12th thoracic and first lumbar vertebral bodies in 90% of dissections.

Conclusions

Trifurcation of the celiac trunk was lower than previously reported. A high proportion of cases with additional vessels were found.

Accessory subscapularis muscle - A forgotten variation?

The quadrangular space is a space in the axilla bounded by the inferior margin of the teres minor muscle, the superior margin of the teres major muscle, the lateral margin of the long head of the triceps brachii muscle and the surgical neck of the humerus, medially. The axillary nerve (C5-C6) and the posterior circumflex humeral artery and veins pass through this space in order to supply their territories. The subscapularis muscle is situated into the scapular fossa and inserts itself into the lesser tubercle of the humerus, thus helping stabilize the shoulder joint. A supernumerary muscle known as accessory subscapularis muscle originates from the anterior surface of the muscle and usually inserts itself into the shoulder joint. It is a rare variation with few reports of its existence and incidence. We present a case of the accessory subscapularis muscle in a male cadaver fixated with a 10% formalin solution. The muscle passed anteriorly to the axillary nerve, thus, predisposing an individual to quadrangular space compression syndrome. We perform a review of the literature and address its clinical, anthropological and anatomical significance.

Effect of Trauma to Primary Tooth on Permanent Maxillary Incisors: A Clinical Case Report

Trauma to primary tooth leads to abnormal variations in crown and root canals of permanent teeth that presents a challenge in diagnosis and clinical management to the practitioner. This article presents a detailed case report of the endodontic treatment of a three canalled maxillary central incisor and maxillary lateral incisor having single canal with open apex linked with periodontal defect. Root canals were prepared with hand files and canals were irrigated with 2.5% sodium hypochlorite solution. Calcium hydroxide was placed as an intracanal medicament. As the expected healing did not occur even after one month of calcium hydroxide therapy, so periapical endodontic surgery was performed using Platelet Rich Plasma (PRP). Satisfactory clinical and radiographic results were obtained at 12 months. Detailed knowledge of the anatomical variations in the root canal and awareness of their configuration is essential for the success of such cases.

Anatomic variation of the abducens nerve in a single cadaver dissection: the "petrobasilar canal"

Anatomic variations of the petrosphenoid ligament, Dorello's canal and the course of the abducens nerve have been extensively described over the past years. In the present report of a single cadaver dissection, we describe an unusual course of the abducens nerve at the level of the petrous bone. The right abducens nerve did not enter Dorello's canal, but ran below the petrous bone through a narrow canal in the petrobasilar suture, which we called the "petrobasilar canal". No anatomic variations of the left abducens nerve were noted.

Commentary on: “Evaluation of variations in sinonasal region with computed tomography”

This letter is a commentary on the article titled “Evaluation of variations in sinonasal region with computed tomography”, published in the January 2016 issue of World Journal of Radiology. The authors definition of the secondary middle turbinate is incorrect. The authors stated that the secondary middle turbinate is an accessory turbinate that is seen between the superior and middle turbinates. It should originate from the middle meatus posterosuperior to the ethmoid infundibulum.

A combined variation of Palmaris longus and Flexor digitorum superficialis: Case report and review of literature

The muscles of the anterior compartment of the forearm often exhibit anatomic variations. During dissection of the upper right limb of a preserved cadaver, morphological variations in the Palmaris longus and Flexor digitorum superficialis muscles were found. The Palmaris longus muscular fibers converged to a tendon that passed beneath the Flexor retinaculum, and inserted at the base of the middle phalanx of the fourth digit, replacing the tendon of Flexor digitorum superficialis. The Flexor digitorum superficialis was divided into two muscular heads: a digastric medial head giving tendons to the second and fifth digits, and a lateral head giving one tendon to the third digit. All these tendons were inserted in the respective digits by two bundles between which were located the tendon of the Flexor digitorum profundus muscle. Variations of flexor muscles must be documented because of their clinical significance and their potential use of these muscles in orthopaedic and reconstructive surgery.

Bilateral Three Rooted Mandibular Premolars and Four Rooted Mandibular First and Second Molar: A Rare Anatomical Variant

The mandibular premolars and molars exhibit wide variations in the form of roots and root canals. A bilateral symmetry of three rooted mandibular first and second premolar and four rooted mandibular first and second molar in a same patient is a rare entity and one such case is presented in this case report.

Anatomic Variant of Liver, Gall Bladder and Inferior Vena Cava

The morphology and relations of liver, gall bladder and inferior vena cava are cardinal. Their anatomical variations may be a reason for the adverse surgical outcome. During routine anatomy dissection of an abdomen, we noticed a variant liver, gall bladder and inferior vena cava in a 63-year-old male cadaver. In the specimen, a retrohepatic segment of inferior vena cava was found to be intrahepatic. On dissection, it was observed that inferior vena cava was covered entirely by a liver tissue on its dorsal aspect. In the same specimen, the gall bladder had undulated inferior surface. On dissection of the gall bladder, numerous mucosal folds were present in the interior. A band of fibrous tissue was found, which was extending from the right side of the gall bladder to the falciform ligament. Hence, preoperative scanning of congenital variations of the liver, gall bladder and inferior vena cava may be compassionate in planning safe surgeries and interventional abdominal procedures.

Extralaryngeal branching of the recurrent laryngeal nerve: a meta-analysis of 28,387 nerves

Introduction

The recurrent laryngeal nerves (RLN) are branches of the vagus nerve that go on to innervate most of the intrinsic muscles of the larynx. Historically, the RLN has been considered to branch after it enters the larynx, but numerous studies have demonstrated that it often branches before. The wide variability of this extralaryngeal branching (ELB) has significant implications for the risk of iatrogenic injury. We aimed to assess the anatomical characteristics of ELB comprehensively.

Methods

Articles on the ELB of the RLN were identified by a comprehensive database search. Relevant data were extracted and pooled into a meta-analysis of the prevalence of branching, branching pattern, distance of ELB point from the larynx, and presence of positive motor signals in anterior and posterior ELB branches.

Results

A total of 69 articles (n = 28,387 nerves) from both intraoperative and cadaveric modalities were included in the meta-analysis. The overall pooled prevalence of ELB was 60.0 % (95 % CI 52.0–67.7). Cadaveric and intraoperative subgroups differed with prevalence rates of 73.3 % (95 % CI 61.0–84.0) and 39.2 % (95 % CI 29.0–49.9), respectively. Cadavers most often presented with a ELB pattern of bifurcation, with a prevalence of 61.1 %, followed by no branching at 23.4 %. Branching of the RLN occurred most often at a distance of 1–2 cm (74.8 % of cases) prior to entering the larynx. A positive motor signal was most often noted in anterior RLN branches (99.9 %) but only in 1.5 % of posterior branches.

Conclusions

The anatomy of the RLN is highly variable, and ELB is likely to have been underreported in intraoperative studies. Because of its high likelihood, the possibility of ELB needs to be assessed in patients to prevent iatrogenic injury and long-term postoperative complications.

Electronic supplementary material

The online version of this article (doi:10.1007/s00423-016-1455-7) contains supplementary material, which is available to authorized users.

Root and Root Canal Morphology of Maxillary First Premolars: A Literature Review and Clinical Considerations

INTRODUCTION

Sound knowledge of the external and internal morphology of the different teeth groups is essential to ensure a successful outcome of root canal treatment. The aims of this study were to review the available literature with respect to the root and root canal morphology of maxillary first premolars and discuss the clinical considerations of this morphology on the various dental procedures.

METHODS

The MEDLINE/PubMed and Scopus databases were searched for relevant literature. The identified publications were classified into anatomic studies and clinical case reports. The data extracted from anatomic studies were tabulated, and weighted averages for certain internal and external morphologic features were calculated. The anatomic and developmental variations in the clinical case reports were summarized.

RESULTS

A total of 92 studies (45 anatomic studies and 47 case reports) including a total of 11,299 teeth were identified. The majority of maxillary first premolars had 1 root (41.7%) or 2 roots (56.6%). Regardless of the number of roots, the vast majority (86.6%) had 2 root canals, with type IV (2-2) being the most common canal configuration (64.8%). The majority of the apical foramina (66.6%) did not coincide with the apical root tip. About 38% of the teeth had lateral canals, 12.3% had apical deltas, and 16.0% had isthmi. The clinical case reports showed that the 3-rooted variant was the most common anatomic variation, and developmental anomalies were rarely reported.

CONCLUSIONS

The maxillary first premolars are predominantly 2-rooted teeth with 2 root canals. However, the clinician should be aware about the possible anatomic variations of these teeth and their relationship with the adjacent anatomic structures while planning and performing endodontic, restorative, periodontal, and surgical procedures.

Role of Anatomic variations of Uncinate Process in Frontal Sinusitis

The osteomeatal complex plays an important role in the development of Chronic rhinosinusitis. The ethmoidal infundibulum is bordered medially by the uncinate process, and the anatomic relationship between the ethmoidal infundibulum and the frontal recess may depend upon the types of attachment of the uncinate process. The osteomeatal complex is the main area targeted in chronic rhinosinusitis and within it uncinate process is the first anatomical structure encountered. The aim of this study was to evaluate the types of attachment of the uncinate process and its implications in the development of sinus inflammation. The significance of anatomical variations of uncinate process in chronic sinusitis were evaluated. A prospective CT scan study on 64 patients of chronic sinusitis (128 uncinate processes) was done. The results were tabulated and analyzed using Statistical Package for Social Science 16.0. Type I superior attachment of uncinate process into the lamina papyracea was the most common variety in all ages and both sexes and a statistically significant association between Type 1 Uncinate process and frontal sinusitis was found. (P < 0.05). The superior attachment of uncinate process alters the frontal sinus drainage and causes the frontal sinusitis.

Prevalence of Elongated Styloid Process in a Central Brazilian Population

BACKGROUND

Eagle's syndrome comprises a rare disorder caused by compression of an elongated or deformed styloid process or ossified/calcified stylohyoid ligament on neural and vascular structures. It is characterized by facial and neck pain and can be confused with a wide variety of facial neuralgias, oral and dental diseases and temporomandibular disorders. An imaging evaluation associated with a careful clinical examination, are mandatory in structuring a correct differential diagnosis and in the establishment of a proper therapeutic protocol.

AIM

To investigate the prevalence of the elongated styloid process in a Central Brazilian population and its relation to gender, age and side.

MATERIALS AND METHODS

Digital panoramic radiographs of 736 patients (412 female and 324 male, with a mean age of 35.03 years) were consecutively selected from a private radiology clinic's secondary database. The apparent length of the styloid process was measured from the point where the styloid left the tympanic plate to the tip of the process by two specialists in dental radiology, with the help of the measuring tools on the accompanying software. Styloid process measuring more than 30 mm was considered elongated. The statistical analysis included frequency distribution and cross tabulation. The data were analysed by using Chi-squared tests. The level of significance was set at 5% for all analyses.

RESULTS

A total of 323 (43.89%) radiographic images were suggestive of elongated styloid process. No statistically significant difference was found between the genders, although a higher prevalence was noticed in female participants. Approximately, 31% of the elongated styloid process was observed in 18-53-year-old participants (p < 0.05). Two hundred and sixty seven styloid processes (36.28%) were elongated on both right and left sides.

CONCLUSION

The prevalence of elongated styloid process was high and no statistically significant correlation was found between the presence of elongated styloid process and the studied variables with the exception of the age.

Ultrasound diagnosis of a ganglion cyst within an extensor digitorum brevis manus muscle

A unique case of a ganglion cyst within the extensor digitorum brevis manus muscle diagnosed by ultrasound in an 18-year-old girl is presented. Different anatomical variations and the clinical importance of this accessory muscle are also discussed.

Right hepatic artery crossing the common hepatic artery: an unusual blood supply to the liver

To perform hepatic surgery a precise preoperative and intraoperative study of liver vascular supply is mandatory. Detecting vascular variations may have great importance on surgical strategy and outcome, and details of anatomy do not concern only academical knowledge but become deeply involved in practice. We present a case of unusual blood supply to the liver, the common hepatic artery was directed to the right liver and a right hepatic artery originating from the superior mesenteric artery was directed to the left liver. The right hepatic artery crossed the common hepatic artery in the proximal part of the hepatic pedicle, anterior to the portal vein. To our knowledge this type of anatomical variation has not been described before and it represents a rare finding that has to be kept in mind, especially in case of major hepatectomies and more demanding splitting liver procedures such as A.L.P.P.S., in situ split, ex situ split and living donor liver transplantation.

"Dysphagia lusoria" - Right subclavian retroesophageal artery causing intermitent esophageal compression and eventual dysphagia - A case report and literature review

•

Case report of a right subclavian retroesophageal artery (RSRA) found occasionaly on a chest CT.

•

The malformation caused intermittent dysphagia.

•

Patient presented with long history of upper digestive symptoms and gastroesophageal reflux disease.

We report a case of an uncommon anatomical anomaly in which a right subclavian retroesophageal artery (RSRA) was discovered during a routine chest CT scan in a patient with intermittent upper digestive symptoms (occasional dysphagia for solids, the so called “globus hystericus”). Subclavian arteries vary in their origin, course or length. RSRA is a relatively common embryological anomaly of the aortic arch. In this case we report a single carotid trunk. This variation is due to interruption of the fourth right aortic arch between the origins to the common carotid artery and subclavian artery, while the fourth left arch is intact. The regression of the proximal portion of the right subclavian artery occurs and the retroesophageal aortic arch persists, rarely leading to symptoms, as were present in this case.

Three superficial veins coursing over the clavicles: a case report

We report a unique bilateral combination of multiple variations in the superficial venous system of the neck of a 77-year-old male cadaver. On the right side of the neck, the external jugular vein (EJV) crossed superficial to the lateral third of the clavicle constituting a common trunk with the cephalic vein (CV) that drained into the subclavian vein (SCV). On the left side the EJV descended distally, passed over the anterior surface of the medial third of the clavicle and drained into the SCV. The posterior external jugular vein (PEJV) crossed superficial to the lateral third of the clavicle and terminated into the CV, providing an additional communicating branch to the EJV. Knowledge of both normal and abnormal anatomy of the veins of the neck plays an important role for anesthesiologists or cardiologists doing catheterization, orthopedic surgeons treating clavicle fractures and general surgeons performing head and neck surgery, to avoid inadvertent injury to these vascular structures.

An analysis of the anatomic variations of the paranasal sinuses and ethmoid roof using computed tomography

OBJECTIVE

To determine the Keros classification and asymmetrical distribution rates of the ethmoid roof and the frequency of anatomic variations of the paranasal sinuses.

MATERIALS AND METHODS

Paranasal sinus scans of 500 patients obtained using computed tomography were evaluated retrospectively. Measurements were performed using a coronal plan with right-left comparison and with distance measurement techniques. The depth of the lateral lamella was calculated by subtracting the depth of the cribriform plate from the depth of the medial ethmoid roof. The results were classified according to their Keros classification. Any asymmetries in the ethmoid roof depth and fovea ethmoidalis configuration were examined. The anatomic variations frequently encountered in paranasal sinuses (pneumatized middle concha, paradoxical middle concha, agger nasi cells, Haller cells, Onodi cells, etc.) were defined.

RESULTS

The mean height of the lateral lamella cribriform plate (LLCP) was 4.92±1.70 mm. The cases were classified as 13.4% Keros Type I, 76.1% Keros Type II, and 10.5% Keros Type III. There was asymmetry in the LLCP depths of 80% of the cases, and a configuration asymmetry in the fovea in 35% of the cases. In 32% of the cases with fovea configuration asymmetry, there was also asymmetry in the height of the right and left LLCP. The most frequent variations were nasal septum deviation (81.8%), agger nasi cells (63.8%), intralamellar air cells (45%), and concha bullosa (30%).

CONCLUSION

Using the Keros classification for LLCP height, higher rates of Keros Type I were found in other studies than in our study. The most frequent classification was Keros Type II. The paranasal sinus variations in each patient should be carefully evaluated. The data obtained from these evaluations can prevent probable complications by informing rhinologists performing endoscopic sinus surgery about preoperative and intraoperative processes.

CBCT diagnosis and endodontic management of a maxillary first molar with unusual anatomy of two palatal canals: A case report

It is crucial for any clinician to have a thorough knowledge about the normal anatomy of tooth and always be vigilant for any variations to ensure endodontic success. An anatomic variant like additional canals in the palatal root of maxillary molar is not commonly reported. This clinical case report presents the application of cone beam computed tomography as a useful imaging technique in endodontics for the management of teeth with aberrant anatomy. Here, maxillary first molar having two canals in the palatal root, two canals in mesiobuccal root and one canal in distobuccal root was managed successfully using cone beam computed tomography scan as a diagnostic aid.