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PubMed2005

Extrahepatic biliary anatomy at laparoscopic cholecystectomy: is aberrant anatomy important?

BACKGROUND: The prevention of major duct injury at cholecystectomy relies on the accurate dissection of the cystic duct and artery, and avoidance of major adjacent biliary and vascular structures. Innumerable variations in the anatomy of the extrahepatic biliary tree and associated vasculature have been reported from radiographical and anatomical studies, and are cited as a potential cause of bile duct injury at cholecystectomy. METHODS: A photographic study of the dissected anatomy of 186 consecutive cholecystectomies was undertaken and each photo analysed to assess the position of the cystic duct and artery, the common bile duct and any anomalous structures. RESULTS: The anatomy in the region of the gallbladder neck was relatively constant. Anatomical variations were uncommon and anomalous ducts were not seen. Vascular variations were the only significant abnormalities found in the present series. CONCLUSION: Anatomy in the region of the gallbladder neck varies mostly in vascular patterns. Aberrant ducts or duct abnormalities are rarely seen during cholecystectomy hightlighting the principle that careful dissection and identification is the key to safe cholecystectomy.

Cholangiography↗
PubMed1989

Axial loading studies of unstable intertrochanteric fractures of the femur.

An experimental four-part unstable intertrochanteric (IT) femoral fracture was created with either a large or small posteromedial fragment (PMF). Sixty-eight adult embalmed femoral anatomic specimens were fractured and subjected to axial loading after fixation. The maximum load prior to failure for femora from the same anatomic specimen was compared to differentiate between different methods of fixation. In the presence of the large PMF variation, anatomic reduction and fixation allowed the femur to resist an average maximum load 57% greater than identical fractures with the fragment excluded. Fixation of the small PMF increased construct strength by an average of 17% over no fixation. The PMF is the keystone to mechanical stability for IT fractures of the femur. When anatomic reduction is possible, its fixation becomes progressively more critical as its size increases.

Aged↗
PubMed2001

Variations of the position of the colon as applied to percutaneous nephrostomy.

The widespread and increasing usage of percutaneous nephrostomy procedures makes an awareness of the anatomical variations of the colon in relation to the kidney essential. Injury to the colon during this procedure is associated with significant morbidity. The aim of this study was to determine the relation of the colon to the insertion line used during a percutaneous nephrostomy and therefore determine whether the colon is at risk of injury. 333 CT-scans taken in a supine position were studied in order to determine the position of both the ascending and descending colon to the percutaneous nephrostomy insertion line on the level of the superior pole, hilum and inferior pole of the kidneys. In the majority of cases, the ascending and descending colon lie anterior to the line of insertion, and were therefore not at risk. However the descending colon was found to be at risk in 16.1% of cases and the ascending colon in 9.0% of cases on the level of the inferior pole of the kidney. The risk was significantly lower on the level of the hilum and superior pole of the kidneys on both sides. Age distribution analysis showed that the colon is rarely at risk under twenty years of age and the highest risk being in the age range above 40 years. Adequate radiographic evaluation is essential before performance of percutaneous nephrostomy procedures, especially to evaluate the position of the colon as related to the inferior poles of the kidneys.

Adolescent↗
PubMed1996

The Buford complex--a variation of normal shoulder anatomy: MR arthrographic imaging features.

OBJECTIVE: The purpose of this study was to show the MR arthrographic imaging features of a normal anatomic variation of the shoulder: the absence of the anterior superior labrum and the presence of a "cordlike" middle glenohumeral ligament,which together are known as the Buford complex. MATERIALS AND METHODS: We retrospectively analyzed the MR arthrographic examinations of 10 patients with arthroscopically proven Buford complexes. RESULTS: MR arthrographic examinations showed an absent anterior superior labrum and an associated cordlike middle glenohumeral ligament in all patients. No contiguous tear of the superior labrum or anterior inferior labrum was evident. Originally, this variation was mistakenly diagnosed as a labral avulsion in two of the 10 patients. Also, a differential diagnosis of a superior labral tear was mistakenly offered for four patients. CONCLUSION: An absent anterior superior labrum and an associated cordlike middle glenohumeral ligament represent the normal variation that is known as the Buford complex rather than an avulsed labrum. This normal variation may be mistaken for a detached labrum.

Adolescent↗
PubMed2001

Rare variations of the mylohyoid muscle: case study.

The mylohyoid is a muscular diaphragm in the floor of the oral cavity. Its superficial and deep surfaces have important anatomical relationships. The submandibular gland is uniquely related to both surfaces at the posterior free edge of the muscle. It is here that the submandibular and sublingual tissue spaces become continuous. This case report describes an unusual range of anatomical variations of the mylohyoid muscle and reviews their clinical significance.

Aged↗
PubMed2005

Are there age induced morphologic variations of the superior glenoid labrum? About 100 shoulder arthroscopies.

Different anterosuperior aspects of the glenoid labrum have already been described and are thought to be normal anatomical variations. The goals of this study were first to characterize these anterosuperior labral morphologies and then to analyze their variations in function of the patients' age. One hundred shoulder arthroscopies were recorded to study the macroscopic characteristics of the anterosuperior labrum of the glenohumeral joint and its relationships with the proximal insertion of the tendon of the long head of the biceps. Then, patients were divided into two groups in function of their age (below and over 30 years old). Morphological modifications of the labrum were found in function of the age of the patient with an increase of the nonpathologic "mobile labrum" type after 30 years (P=0.0423). Therefore a mobile and loosely attached superior labrum should not always be considered as abnormal, especially in case of patient older than 30 years.

Adolescent↗
PubMed1978

[The pulmonary ligament (pulmo-diaphragmatic ligament) (author's transl)].

The paper considers the appearances of the contour of the diaphragm and of the normal irregularities of the diaphragm. The hitherto existing opinion of ill defined or tented diaphragmatic outlines always being the result of pleurodiaphragmatic implications in inflammatory or fibrotic processes in the basis of the lung needs to be corrected: In a great number of p.a. chest roentgenograms of healthy persons a more or less obvious ill definition or tenting of the medial part of the diaphragma can be found, caused by a variation of the pulmonary ligament characterized by its connection with the diaphragmatic pleura. Ill definition and tenting of the diaphragmatic outline caused by this variation of the pulmonary ligament are called physiological alterations, contrary to similar pathological (e.g. adhesive) ones. Only if this anatomical variation exists a pulmonary ligament can be roentgenologically visualized directly.

Diaphragm↗
PubMed1996

Lower limb morphology and risk of overuse injury among male infantry trainees.

The effect of anatomic variation on the risk of overuse injuries has not been adequately evaluated. To determine the association of several common anatomic characteristics (genu varum, genu valgum, genu recurvatum, and lower limb length differences) with risk of overuse injury, we made prospective morphologic measurements of young men prior to beginning 12 week of Army infantry training. The training included frequent running, marching, calisthenics, and other vigorous activities. Lower extremity anatomic landmarks were high-lighted, and front- and side-view photographic slides were taken of the 294 study volunteers. The slides were compute digitized, and the following measures calculated: pelvic width to knee width ratio (to assess genu valgum/varum), quadriceps angle (Q-angle), knee angle at full extension, and lower limb length differences. The cumulative incidence of lower limb overuse injury was 30%. Relative risk of (RR) of overuse injury was significantly higher among participants with the most valgus knees (RR = 1.9). Those with Q-angle of more than 15 degrees had significantly increased risk specifically for stress fractures (RR = 5.4). Anatomic characteristics were associated with several other types of injuries, including pain and nonacute muscle strain due to overuse. This pilot study provides evidence that some lower limb morphologic characteristics may place individuals at increased risk of overuse injuries.

Chi-Square Distribution↗
PubMed2001

The hepatic artery in liver transplantation and surgery: vascular anomalies in 701 cases.

The purpose of this study is to report the variations in hepatic arterial supply of a mixed population of organ donors in which the anatomy was individually examined during the bench surgery, and patients who underwent a selective angiogram of the celiac axis and superior mesenteric artery. We reviewed the donor forms and/or angiograms of 701 patients. The donor forms were completed personally by one of the authors, while all the radiology images were obtained through studies performed by one single radiologist. The arterial anatomy was anomalous in 296 out of 701 cases with an overall incidence of hepatic artery anomalies of 42.22%. In this paper we describe previously unreported arterial anomalies of the hepatic artery, collecting the second largest series of hepatic artery anatomical variations of the English literature. This anatomical update can be useful for transplant and general surgeons, as well as vascular radiologists.

Female↗
PubMed2004

Sonographic imaging of the sciatic nerve and its division in the popliteal fossa in children.

BACKGROUND: High resolution ultrasound is a possible option for anesthetists to detect nerves. We tested the possibility of imaging the sciatic nerve and its division into the tibial and peroneal part using high resolution ultrasound in children. METHODS: Twelve children up to 45 kg body weight were randomly selected. Using a handheld ultrasound system with a 10 MHz linear array probe the popliteal fossa and the back of the thigh were examined and measured. The sciatic nerve and its division were depicted by ultrasound. RESULTS: The sciatic nerve and its division could be displayed in all children. The position of the nerve division showed large anatomical variation. CONCLUSIONS: Ultrasound opens a window to detect the anatomy of the sciatic nerve in children. In addition, the surrounding anatomical structures can also be depicted. The results suggest a possibility of safe placement of a cannula for blockade of the sciatic nerve under visual control.

Child↗
PubMed1990

Subtle variations in tubal anatomy in infertile women.

The frequency of tubal variations was recorded in 100 infertile and 100 fertile women at cesarean section. The infertile women had significantly more tubal/pelvic anatomical variation than did their fertile counterparts. Fimbrial agglutinations (25%), accessory tubes (13%), accessory ostia (10%), phimoses (13%), and sacculations (7%) were found more commonly in the infertile women. Paratubal cysts were found with equal numbers in both groups. There was no statistical difference in history of sexually transmitted disease/pelvic inflammatory disease (PID) or endometriosis. No significant relationship between a positive PID history and fimbrial agglutination was found; the majority of agglutinations were present with no associated adhesions.

Fallopian Tubes↗
PubMed1983

[Correlation between standard radiology and computed tomography in the demonstration of mediastinal lines].

The mediastinal lines correspond to the contours of the middle and upper mediastinum, and represent the edges of a dense, pleural covered structure marginated by the air within the lung. The mediastinal lines derive their names from the adjacent organs: 1) The posterior mediastinal junction line (where both lungs meet posteriorly, just before the vertebral column). 2) The anterior mediastinal junction line (where both lungs meet anteriorly, behind the sternum). 3) The right paratracheal stripe (where the right lung meets the trachea). 4) The esophageal-pleural stripe (which disappears at the level of the arch of the Azygos vein that divides the right lung from the esophagus. 5) The Azygos-pleural line (where the arch of the Azygos vein meets the right lung). 6) The esophageal-pleural line (where the right esophageal wall meets the right lung). 7) The para-aortic line (that is the most constant). 8) and 9) The left and right paraspinous lines (whereof the right is the most often visible). The absence of one of the mediastinal lines is sometimes insignificant, since it can be caused by anatomical variations or by the conditions of the picture. C.T. explains the formation's mechanism of these mediastinal lines, explains the anatomic reasons for their possible absence or displacement and often provides us with their etiology. C.T. offers a simple, reliable and atraumatic method in cases of displaced or vanished mediastinal lines, and should replace standard tomography of the mediastinum.

Humans↗
PubMed2005

Topographic variations of the relationship of the sciatic nerve and the piriformis muscle and its relevance to palsy after total hip arthroplasty.

The aim of this paper was to study the anatomical relationship between the piriformis muscle and the sciatic nerve with regard to the possibility of neurological deficit after THA. The incidence of anatomical variation of both structures is 15-30% in the literature. The authors studied 91 cadavers and found an atypical relationship in 19 cases (20.9%). In this study individual variations were found with the following frequency: The sciatic nerve exits below the piriformis muscle in 79.1% of the cases. The sciatic nerve separates into two divisions above the piriformis, one branch passing through the muscle, the other below it (14.3%). An unsplit nerve passes through the piriformis muscle in 2.2%. The nerve separates into two divisions above the piriformis, one branch exiting above the muscle and passing along its dorsal aspect, the second exiting distally below the muscle in 4.4%. The most common reasons for sciatic nerve injury in surgery of the hip joint are direct injuries, ischemia of the nerve tissue, compression or excessive distraction of the nerve, compression by bone cement, thermal damage during cement polymerization, injury during THA dislocation, compression by hematoma, bone prominence or an implanted acetabular component. According to the presented anatomical study, overstretching of the nerve itself or its branches in the area of the pelvitrochanteric muscles after their release from their origin can be another mechanism. Such overstretching can appear in the presence of some of the aforementioned anatomical variants.

Arthroplasty, Replacement, Hip↗
PubMed1995

The radial sensory nerve entrapped between the two slips of a split brachioradialis tendon: a rare aspect of Wartenberg's syndrome.

A retrospective study was designed to verify how often an anatomic variation caused the radial sensory nerve entrapment at the forearm (Wartenberg's syndrome). This variation, in which the superficial branch of the radial nerve emerges from under the fascia between two slips of a split brachioradialis tendon, was mentioned once in a clinical textbook as a basis for nerve entrapment but was found to occur in 5 of 150 dissected arms in 4 of 75 cadavers (3.3% of the investigated arms) in a recent anatomic study. To evaluate the incidence of this variation, 143 operative reports from patients who had Wartenberg's syndrome were reviewed. The variation was observed in seven patients. We conclude that any operation for Wartenberg's syndrome should include a thorough investigation of the site where the radial sensory nerve emerges from under the fascia and, if the nerve emerges through a split brachioradialis tendon, the anomalous tendon slip should be divided.

Forearm↗
PubMed2001

Technical challenges of hepatic venous outflow reconstruction in right lobe adult living donor liver transplantation.

A right lobe graft that is drained by the right hepatic vein (RHV) is obtained by transecting the liver on the right side of the middle hepatic vein (MHV). On occasion, a small RHV that only drains a portion of the right lobe, with the predominant outflow achieved by the MHV, is encountered. If such variation is not recognized while performing right lobe liver transplantation and the RHV only is used for reconstruction, venous outflow obstruction with subsequent graft congestion and eventual graft failure will occur. Additionally, preservation of the main MHV and its branch drainage of the left lobe is crucial to avoid outflow blockage to the remaining segment 4 in the donor. We report 4 cases showing a variant type of small RHV and large MHV branch that drain not only segments 5 and 8, but also segments 6 and 7. These variations were simultaneously associated with a large-caliber inferior RHV that also required reconstruction. The methods used to diagnose such anatomic variations and the techniques for reconstruction in the donor and recipient are described.

Adult↗
PubMed2004

A variation of the radial artery and its clinical implications for coronary artery bypass grafting.

Since the radial artery is increasingly harvested as a bypass graft, surgeons are confronted with its anatomical variations. We report on a radial artery running laterally around the distal part of the radius, while a superficial palmar branch is running straight down. The radial artery can be dissected distally to get enough length for the bypass graft, but attention has to be paid to the superficial branch of the radial nerve running nearby to prevent postoperative paresthesias and numbness. The superficial palmar branch of the radial artery can be ligated. Allen's test in such a case is not valid because it is always negative.

Aged↗
PubMedDate not supplied

A critical re-appraisal of lymph-venous shunt in the management of massive ascites.

Lymph-venous shunt is one of most investigated procedures in the management of intractable ascites. However, there is considerable variation in the reported results. Personal experience with twenty-one operated cases reveals a dubious role for this intervention. Frequent anatomical variations and uncertain role and incidence of duct-end stenosis, in our opinion, reduces the efficacy of the procedure.

Adult↗