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At least 1,279 records · Page 71Linked to original sources
PubMed2003

[Normal anatomical variants of the superior labrum biceps tendon anchor complex. Anatomical and magnetic resonance findings].

There are difficulties in diagnosing pathologies of the labrum-biceps tendon complex (LBTC) because of the great individual variability of this structure. Anatomical variations, such as the sublabral recess, are frequently found and can also be misinterpreted as Andrews or SLAP II lesions. The etiology and mechanisms of creating such a sublabral recess are not exactly known. The examination of 31 cadaveric shoulder specimens from an age group between 49.3 and 83.6 years showed a sublabral recess in 63.6-85%. This high frequency of sublabral detachment of the labrum in older patients indicates that according to the high range of motion of the humeral head and therefore the changing angle of the long biceps tendon (LBS) a certain mobility of the superior LBTC is physiological and should not necessarily be seen as a sign of instability. Besides mobility-increasing factors such as overhead professions and sports with high repetitive maximal abduction and external rotation and the individual age, the type of insertion of the LBT at the glenoid influences the development of sublabral recess. Accordingly, posterior oriented insertion types of the LBT determine deeper and more posterior oriented sublabral recesses whereas in cases of anterior directed types of insertions no or less deep recesses can be found. Anamnestic aspects, such as the mechanism of injury and overhead activities, these macroscopic and functional associations in MR arthrography and arthroscopic inspection have to be considered in order to differentiate between physiological and traumatic changes of the labrum-biceps tendon complex.

Aged↗
PubMed2002

The anterior inferior tibiofibular ligament and talar impingement: a cadaveric study.

Impingement by the distal fascicle of the anterior inferior tibiofibular ligament (AITFL) is a relatively new entity among the known causes of anterolateral impingement syndromes of the ankle. This study investigated the anatomy of the anterior inferior tibiofibular ligament and its possible role in talar impingement in 47 ankles of 27 cadavers. The length, width, insertion point to the fibula and the interactions with talus were noted, as was the relationship of the fascicle and talus during different ankle movements before and after incision of the lateral ligaments. A distal fascicle of the AITFL was found in 39 of the 47 ankles (83%) and appeared as a single-complete ligament in the remaining 8 ankles (17%). The fascicle averaged 16.1+/-2.94 mm in length (range 10-21) and 4.2+/-1.00 mm in width (range, 3-7). The insertion point of the fascicle on the fibula averaged 10.3+/-2.27 mm (5-13) distal to the joint level. Contact between the ligament and the lateral dome of the talus was observed in 42 specimens (89.3%). Bending of the fascicle was observed in 8 of these 42 ankles with forced dorsiflexion. These 8 specimens were significantly wider and longer than the specimens without bending of the fascicle. Incision of the anterior talofibular ligament led to bending in dorsiflexion in additional 11 ankles. The total 19 fascicles with bending after incision of the anterior talofibular ligament were significantly longer and inserted more distally than the remaining 20 fascisles without bending. Manual traction simulating distraction during arthroscopic procedures relieved the contact. These findings show that the presence of the distal fascicle of the AITFL and its contact with the talus is a normal finding. However, it may become pathological due to anatomical variations and/or instability of the ankle resulting from torn lateral ligaments. When observed during an ankle arthroscopy, the surgeon should look for the criteria described in the present study to decide whether it is pathological and needs to be resected.

Biomechanical Phenomena↗
PubMed2004

Endovascular treatment of the posterior inferior cerebellar artery aneurysms.

Aneurysms may arise at various locations along the course of the posterior inferior cerebellar artery. Brainstem and cranial nerves manipulation make the surgical approach to proximal aneurysms difficult, while the occlusion of the parent vessel is sometimes unavoidable in peripheral aneurysms. Endovascular treatment can be a good alternative, but also with this approach the location of the aneurysm is critical. If occlusion of the parent vessel is planned, anatomical variations and vascular territories of the brainstem should be considered. We report our experience with 18 consecutive aneurysms (12 proximal, 6 peripheral) treated by coils. Complete occlusion was achieved in 14 patients and subtotal in 4. In three patients the parent vessel had to be sacrificed. During treatment two perforations occurred; aneurysms were completely occluded without clinical consequences. Two small asymptomatic cerebellar infarctions were seen on postoperative computed tomography. Clinical outcome was good in 16 patients.

Adult↗
PubMed2006

Anatomical study of the confluence of the sinuses with contrast-enhanced magnetic resonance venography.

INTRODUCTION: It is important that each dural sinus can be recognized during brain surgery and that the venous route can be used for interventional procedures. In this study, the anatomical features and patterns of the confluence of the sinuses were analyzed. METHODS: The technique of contrast-enhanced three-dimensional magnetic resonance venography was used in 549 patients. RESULTS: There were many anatomical variations in the confluence of the sinuses. Most cases had wide communication between the right and left transverse sinuses. CONCLUSION: Careful examination of the confluence of the sinuses is essential for the preoperative evaluation of posterior cranial fossa lesions and interventional procedures using the venous route.

Adolescent↗
PubMed2002

Magnetic resonance imaging of the shoulder: a review of potential sources of diagnostic errors.

Shoulder magnetic resonance (MR) imaging and MR arthrography are frequently utilized in the evaluation of shoulder pain and instability. The clinical scenario and imaging findings may be confusing to clinicians and radiologists and may present diagnostic challenges for those involved in evaluating and treating shoulder pathology. Often rotator cuff and labral abnormalities may be coexistent, clinical manifestations of denervation syndromes may be confusing to clinicians, and normal anatomic variations, imaging pitfalls, and various artifacts may cause dilemmas for the radiologist. This article will review the most frequently encountered mimickers and pitfalls of MR imaging of the shoulder.

Artifacts↗
PubMed1997

Malposition of the tibial tubercle during flexion in knees with patellofemoral arthritis.

OBJECTIVE: To assess the mechanisms contributing to the induction of patellofemoral arthritis (PF-OA). DESIGN AND PATIENTS: A computed tomography scan was taken at three levels of the lower extremity in full extension and at 30 degrees of flexion. The cuts were superimposed and 12 parameters were compared in 17 PF-OA knees and 27 normal knees to assess the rotation angle of the tibial tubercle. RESULTS: Although the tibial tubercle was in almost the same position in full extension in the normal and PF-OA knees, it was positioned significantly laterally at 30 degrees of flexion in PF-OA knees. Also the articular surface of the lateral femoral condyle was significantly narrower or steeper in PF-OA knees. CONCLUSION: Anatomic variations and mechanical abnormalities were identified in the PF-OA knees.

Adult↗
PubMedDate not supplied

Secretin-stimulated MRCP.

Secretin-stimulated magnetic resonance cholangiopancreatography not only facilitate the depiction of anatomic variations or morphologic changes of the pancreatic duct in the normal and diseased pancreas but also help assessing functional abnormalities of the exocrine pancreas. In this article, we illustrate findings of normal pancreas and various pancreatic diseases on magnetic resonance cholangiopancreatography after secretin stimulation.

Cholangiopancreatography, Magnetic Resonance↗
PubMed2006

Using the ovarian vein to find the ovary.

Computed tomograms of 68 adult women who had undergone contrast-enhanced, 5-mm helical computed tomography of the abdomen and pelvis were retrospectively reviewed to determine whether the ovarian vein could be used to locate the ovary. Subjects were 17 to 84 years of age (mean 45 years); 31 scans were normal, and 37 showed pelvic masses. Both ovarian veins were identified at their termination and were followed into the pelvis by scrolling through the set of venous phase images with a manual cine-paging tool. All 68 left ovarian veins and 67 of 68 right ovarian veins were identified. All visualized ovarian veins led to a normal ovary or to an ovarian mass. There were no anatomic variations. In 13 ovaries displaced by pathology in the pelvis, the ovarian vein was correspondingly displaced and indicated the altered ovarian position. In all 14 patients with non-ovarian pelvic masses, ovarian veins led to the normal ovary; the vein and ovary were markedly displaced in three of these patients. On computed tomography, the ovarian vein can be consistently identified. By tracing the vein into the pelvis, the ovarian or non-ovarian nature of a pelvic mass can be determined.

Adolescent↗
PubMedDate not supplied

CT of Nissen's fundoplication.

The aim of this work is to describe the computed tomographic (CT) anatomy in patients who underwent Nissen's fundoplication. Forty patients (mean age = 61 years) with peptic esophagitis (nine cases), refractory gastroesophageal reflux (11 cases), and hiatal hernia (20 cases) were studied. Examinations were performed by third-generation CT equipment, with patients in the prone position after the ingestion of gastrovison and barium paste. In 34 patients, the examination demonstrated anatomical variations related to surgery, that is, the presence of a soft tissue mass at the level of the distal third of the esophagus. In four patients, a functional incompetence of the fundoplication (three cases) and a recurrent hiatal hernia (one case) were demonstrated. Our results suggest a possible application for CT study in postoperative follow up of patients who undergo Nissen's fundoplication, complementary to endoscopy and functional exams.

Case-Control Studies↗
PubMed2001

Endoscopic carpal tunnel release and nerve conduction studies.

We investigated the outcome of endoscopic carpal tunnel release (ECTR) for patients with carpal tunnel syndrome (CTS) in comparison with the results of preoperative nerve conduction studies. The compound muscle action potential (CMAP) of the abductor pollicis brevis muscle (APB) and the second lumbrical muscle (L2) was recorded following median nerve stimulation at the wrist. A total of 38 hands in 35 patients were classified into four categories. Hands with a similarly prolonged distal motor latency for the APB and L2 were classified as type I (n=25), while those with a more prolonged distal motor latency for the APB than for the L2 (>0.7 ms) were classified as type 2 (n=10). Hands with a CMAP for the APB, but not L2, were classified as type 3 (n=1), and hands with no CMAP for either the APB or L2 were classified as type 4 (n=2). After ECTR, all of the type 1 and 2 hands were improved. Patients with type 3 and type 4 hands did not show satisfactory improvement, which may have been due to anatomical variation of the recurrent motor branch of the median nerve.

Action Potentials↗
PubMed2007

Computer-assisted operative planning in adult living donor liver transplantation: a new way to resolve the dilemma of the middle hepatic vein.

An adequate venous outflow is essential for securing viability of both graft and remnant in adult living donor liver transplantation (ALDLT). Seventy-five potential live liver donors were evaluated for LDLT by means of an "all-in-one" CT, which defined the biliary tree, portal vein, hepatic artery, and hepatic vein anatomy. The acquired data sets were further analysed by means of the software HepaVision (MeVis, Germany). Only a minority (29%) of potential donors were found to have a vascular and biliary anatomy consistent with the classically described "normal" patterns. The vast majority (71%) had "anatomical variations". Thirty-nine (52%) donors underwent ALDLT hepatectomy. The right hepatic vein was dominant in 64 cases, representing 48 +/- 6% of the total liver volume (TLV). The middle hepatic vein was dominant in 11 cases, making up 40 +/- 8% of the TLV. The left hepatic vein was never dominant. The volume contribution of the middle hepatic vein (MHV) was 114-782 ml for the right and 87-419 ml for the left hemiliver. Computer-assisted planning allows for the 3D reconstruction of the vascular and biliary anatomy, automatic calculation of the total and territorial liver volumes, and risk analysis of hepatic vein dominance relationships. This comprehensive data acquisition supports preoperative evaluation and provides a high degree of safety for donors and improved outcomes for recipients.

Adolescent↗
PubMedDate not supplied

A proposed anatomic typing of the right internal spermatic vein: importance for percutaneous sclerotherapy of varicocele.

PURPOSE: To classify the anatomic types of the right internal spermatic vein (ISV). METHODS: We evaluated venograms obtained in 150 consecutive patients with idiopathic varicocele referred for transfemoral sclerotherapy. RESULTS: Six anatomic types of the right internal spermatic vein (ISV) were recognized. These were classified by the location of their orifices and the tributary venous patterns. In roughly half the patients (53%), the ISV appeared as a simple vein with no remarkable retroperitoneal interconnections. In the remainder, complex retroperitoneal anastomoses were encountered. CONCLUSION: By understanding these anatomic variations, the angiographer can approach treatment of right-sided varicocele with foreknowledge of the nature of these types and the presence of valves and collaterals.

Adult↗
PubMed2000

A surgical approach to the ventral aspect of the lumbar vertebrae in the sheep model.

The sheep model is frequently used for pre-clinical trials of spinal implants and vertebral interbody fusion devices. The lack of a well-documented multisegmental approach to the ventral aspect of the lumbar vertebrae has limited these trials to a posterior approach to the spine. A retroperitoneal approach to the sheep lumbar vertebrae was established and tested. One hundred and five sheep underwent the surgery. No major complications are reported. Major anatomical differences between sheep and humans were observed and documented. Anatomical variations in the sheep segmental vessel anatomy were also observed. Comprehensive knowledge of the retroperitoneal approach in sheep will facilitate pre-clinical studies testing ventral spinal implants or fusion techniques.

Animals↗
PubMed2000

An accessory belly of the abductor digiti minimi muscle: a case report and embryologic aspects.

Accessory fasciculi of the hypothenar muscles have been involved in vascular and nerve compressions. During a routine dissection an accessory belly of the abductor digiti minimi muscle arising from the tendon of the palmaris longus muscle was found in the lower third of the forearm. The accessory fasciculus ran through Guyon's canal enclosing the ulnar nerve and vessels. It was attached by means of two tendons where the fibres of the abductor digiti minimi muscle ended in a single pennate form. This anatomic variation was associated with a marked reduction of the caliber of the fourth tendon of the flexor digitorum superficialis muscle and a split of the median nerve. The nerve supply arose from the ulnar nerve. A fibrous band originating from this accessory muscular belly was found covering the median nerve. Based on the development of muscles and fibrous structures within the hand and forearm, as well as on our results, we consider the present anomalies as an unusual persistence of an undifferentiated group of mesenchymal cells. These belong to the superficial muscular anlagen layer of the hand, just between the flexor digitorum superficialis muscle blastema (which has the capacity of migration) and that for the abductor digiti minimi muscle.

Aged↗
PubMed2001

Bilateral origin of the internal thoracic artery from the third part of the subclavian artery: a case report.

The routine use of the internal thoracic artery (ITA) as a conduit in coronary artery bypass grafting surgery has highlighted the need to appreciate this vessel's anatomic variations. The usual origin of this vessel is from the first part of the subclavian artery, occasionally from the second and rarely from the third. Henriques-Pino and Prates described a unilateral origin from the third part on the left and Vorster et al on the right. Our cadaveric case report presents an unusual bilateral origin of the ITA arising from the third part of the subclavian artery in a 25-year-old Black South African female. The ITA arose from the ventral aspect, 7.3 cm on the right side and 8.5 cm on the left side from the origin of the subclavian artery, and inclined acutely inferiorly and medially, anterior to the distal attachment of the scalenus anterior m., followed the inner border of the first rib for a short distance and, thereafter, continued its usual course in the thorax. This appears to be the first case report presenting a bilateral origin of the ITA from the third part of the subclavian artery.

Adult↗
PubMed2001

Thyrolingual trunk arising from the common carotid artery: a case report.

During a cadaver dissection in the anatomy department of the University of Liege, Belgium, an anatomic variation of the superior thyroid and lingual arteries was observed on the right side in a 68-year-old woman. Both arteries arose from a common trunk located 30 mm beneath the carotid bifurcation. After a 5.2 mm course, the thyrolingual trunk divided into superior thyroid and lingual arteries which followed an unusual course towards their respective organs. Knowledge of this anomaly is important for those who are involved with neck surgery and anatomy.

Aged↗
PubMed2001

Bilateral case of superficial ulnar artery originating from axillary artery.

During the dissection of an 86-year-old male human cadaver, superficial ulnar arteries were found in both upper limbs. These arteries branched from the axillary arteries. In the left arm, the artery crossed ventral to the medial root of the median nerve before running towards the medial part of the arm. The persistence of the median artery was noted. In the right arm, the ulnar artery had a common origin with the subscapular artery. It crossed anterior to the lateral root of the median nerve and then, in the arm, ran alongside the anterolateral aspect of the median nerve, near the biceps brachii muscle, which was supplied by this superficial ulnar artery. Then the artery crossed the median nerve and the brachial artery. The embryology, incidence and clinical relevance of this anatomical variation are discussed. So this was a rare case where the ulnar arteries originated from the axillary artery on both sides, but then followed different courses in the arm and, on the right side, the superficial ulnar artery partly supplied the biceps brachii muscle.

Aged↗