A morphological study of the inferior phrenic arteries on multidetector computed tomography and angiography.

INTRODUCTION: The inferior phrenic artery is a paired artery with a variable origin and course, primarily supplying the diaphragm, but also the suprarenal glands, inferior vena cava, stomach, and oesophagus. The aim of this study is to investigate the origin and course of the inferior phrenic arteries on multidetector computed tomography and angiography. MATERIALS AND METHODS: The anatomy of the inferior phrenic artery was analysed on 2449 multidetector computed tomography scans. Three-dimensional reconstructions were made of the main variations. Additionally, the course and branching pattern of the inferior phrenic artery were descriptively analysed in a cohort of 28 angiograms. RESULTS: In 565 (23.1%) cases the inferior phrenic arteries arose as a common trunk and in 1884 (76.9%) cases as individual vessels. The most common origins of a common trunk were the coeliac trunk (n=303; 53.6%) and abdominal aorta (n=255; 45.1%). The most common origins of the right inferior phrenic artery were the coeliac trunk (n=965; 51.2%), abdominal aorta (n=562; 29.8%) and renal arteries (n=214; 11.4%). The most common origins of the left inferior phrenic artery were the coeliac trunk (n=1293; 68.6%) and abdominal aorta (n=403; 21.4%). CONCLUSION: The inferior phrenic artery has a very variable anatomy. The most common origins of the inferior phrenic artery are the coeliac trunk and its branches, the abdominal aorta, and the renal arteries.

Variant origins of the middle colic artery from the coeliac trunk and its branches.

The middle colic artery usually arises from the superior mesenteric artery, but in rare cases it may arise from the coeliac trunk or its branches. The aim of this study was to investigate variant origins of the middle colic artery on computed tomography and anatomical dissection. Variant middle colic arteries were identified on computed tomography as part of an ongoing study investigating anatomical variations of vessels of the upper abdomen. Three-dimensional reconstructions were made to demonstrate the variant findings. Cadaveric dissections were performed as part of a routine dissection course. We report five cases of rare variant origins of the middle colic artery arising from the coeliac axis. Among these sites of origin were the coeliac trunk, the gastrosplenic trunk, the splenic artery, and the common hepatic artery. Four cases were identified on multi-detector computed tomography and one in a cadaver. In all cases, the vessels passed posterior to the body of the pancreas before entering the transverse mesocolon. Knowledge of middle colic artery variations is important to prevent inadvertent injury in digestive surgery, especially in the hepatopancreatic area. Variant origins of the middle colic artery are rare, and their knowledge is crucial to prevent unnecessary iatrogenic injury during abdominal surgery.

Two arterial variations of the hand and wrist present bilaterally (persistent median artery and superficial dorsal branch of the radial artery): ultrasound findings.

PURPOSE: Arterial variations of the upper limb may bear high importance for many clinical procedures, including the use of flaps in plastic surgery. We present a feasible way for visualization and confirmation of presence of these variations. METHODS: All variations were detected by ultrasonography and confirmed by Color Doppler Imaging. Proper documentation was taken in order to present our findings. RESULTS: We report a case of a 19-year-old female who showed two concomitant arterial variations of the forearm and the hand bilaterally. These two variations were the persistent median artery and the superficial dorsal branch of the radial artery which both significantly contributed to the blood supply of the hand. All examinations were performed by the same investigator and all findings were reviewed by an experienced sonographist. CONCLUSION: An unusual arrangement of the arterial system can be easily detected. We present a feasible way to prevent iatrogenic injuries and increase utilization of anatomical variants knowledge in surgery by using ultrasound prior to planning surgical procedures.

Variations of the lumbrical muscles of the hand: Systematic review and meta-analysis.

PURPOSE: Lumbrical muscles of the upper limb belong to the middle group of intrinsic hand muscles. Their anatomical variability has been extensively studied with heterogeneous findings. Therefore, the aim of this study is to provide a systematic review and a meta-analysis of the lumbrical muscles variations in the human hand. METHODS: For this purpose, four major electronic databases were searched to identify eligible studies. Then, all relevant data were extracted, and statistical analysis performed. A new classification of lumbrical muscles variations is proposed to summarize and clearly define all described findings. We included 26 studies, making a total sample of 1340 dissected hands. FINDINGS: The most common variations for each muscle were an accessory belly for the first lumbrical muscle, a variable origin for the second lumbrical muscle, a variable innervation for the third lumbrical muscle and a variable insertion for the fourth lumbrical muscle with the prevalence 3.8%; 7.7%; 12% and 5.8%, respectively. CONCLUSIONS: We believe that results of our statistical analysis are suitable for both hand surgeons and other medical professionals dealing with hand injuries or functional problems in their daily routine.

An accessory muscle belly or an accessory muscle head? An unusual arrangement of muscles in the anterior compartment of the forearm.

PURPOSE: Knowledge of the unusual arrangement of the flexor pollicis longus (FPL) muscle is important as the variable tendon may be a rare cause of carpal tunnel syndrome. METHODS: During a routine dissection at the Department of Anatomy, an unusual formation of the FPL muscle was observed in a formalin embalmed Central European cadaver. RESULTS: This report presents a variation of the FPL muscle, where the muscle split and formed a separate accessory head inserting into the first lumbrical muscle. Moreover, a tendinous interconnection was present between the FPL muscle tendon and the tendon of the aberrant muscle head. CONCLUSION: The cases described by previous literature, concerning the Linburg-Comstock variation or the accessory head of the first lumbrical muscle originating from the FPL muscle, are closest to the present case. Such variation has a clinical significance ranging from the functional limitation of the thumb and index finger movement to the potential median nerve compression.

A meta-analysis on the anatomical variability of the brachial plexus: Part III - Branching of the infraclavicular part.

INTRODUCTION: The anatomy of the brachial plexus has been a subject of interest to many researchers over time resulting in an inconsistent amount of data. Previously, our team had published two evidence-based studies on the anatomical variations involving the brachial plexus, therefore the aim of this study was to analyze the findings regarding the infraclavicular part of the brachial plexus with the use of meta-analytic techniques to complete the comprehensive series. MATERIAL AND METHODS: Major scientific databases were extensively searched to compile anatomical studies investigating the morphology of the infraclavicular part of the brachial plexus. Extracted data were classified based on our proposed classification system and subsequently analyzed with the use of random effects meta-analysis to state the pooled prevalence estimates of the distinct variation patterns. RESULTS: A total of 75 studies (4772 upper limbs) were selected for the meta-analysis. The branches of the lateral cord, including the lateral pectoral nerve and musculocutaneous nerve, resembled their usual origin in 76.8% (95% CI 50-96%) and 98.8% (95% CI 98-100%), respectively. The medial pectoral nerve, medial brachial cutaneous nerves, medial antebrachial cutaneous nerve and ulnar nerve emerging from the medial cord were observed originating from their usual origins in 90.9% (95% CI 68-100%), 90.7% (95% CI 73-100%), 87.9% (95% CI 67-99%) and 97.7% (95% CI 94-100%), respectively. Lastly, nerves branching from the posterior cord, including the superior and inferior subscapular nerves, thoracodorsal nerve, axillary nerve and radial nerve, originated as per textbook description in 90.7% (95% CI 80-98%), 76.1% (95% CI 61-89%), 90.1% (95% CI 84-95%), 79.8% (95% CI 68-90%) and 99.0% (95% CI 96-100%), respectively. Moreover, the usual origin of the median nerve from the lateral and medial cord via the corresponding roots was encountered in 89.7% (95% CI 84-95%) of cases. CONCLUSIONS: The nerves originating from the infraclavicular part of the brachial plexus exhibit a wide spectrum of possible origins. However, the usual patterns were significantly the most common types present in more than three quarters of cases. Especially clinicians might profit from the enhanced understanding of the brachial plexus anatomy presented herein, since we offer a strong guide for handling the anatomically challenging pathologies in this specific area.

The dorsal pancreatic artery: A meta-analysis with clinical correlations.

BACKGROUND/OBJECTIVES: The dorsal pancreatic artery is the main artery of the body and tail of the pancreas. Its origin and branching is highly variable. The aim of this study was to perform a meta-analysis to generate pooled prevalence data on the presence and origin of the dorsal pancreatic artery. Clinically important aspects of the dorsal pancreatic artery were summarised during the literature review. METHODS: Major medical databases were searched. Data on the presence and point of origin of the dorsal pancreatic artery were extracted and quantitatively synthesised. The obtained data of anatomical based studies and computed tomography based studies were statistically analysed. RESULTS: In total, 30 studies, comprising 2322 anatomical and computed tomography based cases were included. The dorsal pancreatic artery was present in 95.8% of cases. It originated from the splenic artery in 37.6% of cases, common hepatic artery in 18.3% of cases, coeliac trunk in 11.9% of cases and the superior mesenteric artery in 23.9% of cases. Other rare origins were present in 2.77% of cases. Multiple dorsal pancreatic arteries were found in 1,7% of cases. There was no significant difference in the presence or origin of the dorsal pancreatic artery between anatomical and computed tomography based studies. CONCLUSION: The dorsal pancreatic artery is present in the vast majority of cases. Its origin and branching are highly variable. Multiplicity of the dorsal pancreatic artery is infrequent.

A meta-analysis on the anatomical variability of the brachial plexus: Part II - Branching of the supraclavicular part.

INTRODUCTION: The anatomy of the supraclavicular part of the brachial plexus is highly variable, therefore the aim of this study was to perform a systematic review and meta-analysis of the various origins of the long thoracic, dorsal scapular, suprascapular and subclavian nerves. MATERIALS AND METHODS: Major electronic databases were searched to identify all cadaveric studies investigating the morphology of the supraclavicular part of the brachial plexus. Data on the origins of these nerves were extracted and classified. A random effects meta-analysis was performed to state the pooled prevalence estimates. RESULTS: A total of 26 studies, constituting a total of 1021 cases, were deemed eligible for inclusion into the meta-analysis. The usual origin of the long thoracic nerve from the C5, C6 and C7 roots was observed in 78.1% (95% CI 69.4-86.7%) of cases and 21.9% (95% CI 13.3-30.6%) had unusual origins. An accessory long thoracic nerve occurred in 0.3% (95% CI 0-0.7%) of cases. The overall prevalence of the dorsal scapular nerve arising from its usual origin the C5 root was found in 85.2% (95% CI 75.7-94.6%) of cases, while 14.8% (95% CI 5.4-24.3%) appeared abnormal. The suprascapular nerve emerged from its usual point on the superior trunk in 89.8% (95% CI 85.1-94.4%) of cases and in 10.2% (95% CI 5.6-14.9%) of cases had a variable origin. An accessory suprascapular nerve was present in 0.2% (95% CI 0-0.6%). Two possible sites of origin of the subclavian nerve were noted and the typical origin from the superior trunk was found in 98.3% (95% CI 96.3-100%) of cases and variable origin from the C5 root in 1.7% (95% CI 0-3.7%). All unusual origins of each nerve were much less common. CONCLUSIONS: The nerves emerging from the supraclavicular part of the brachial plexus express a wide spectrum of potential origins. Based on their various origins, a new classification system for all the nerves belonging to the supraclavicular part was proposed. Knowledge of these variations and their prevalence data is important to prevent iatrogenic injuries and to state useful landmarks for interventions in the axilla.

A meta-analysis on the anatomical variability of the brachial plexus: Part I - Roots, trunks, divisions and cords.

INTRODUCTION: The brachial plexus is a complex anatomical structure that gives rise to all the nerves of the upper limb. Its variability is frequently observed and represents a challenge for interventions in the lower neck and axilla. The aim of this study was to present a comprehensive and evidence-based review with meta-analytic techniques on the variability of roots, trunks, divisions and cords of the brachial plexus. MATERIALS AND METHODS: Major medical databases were searched to identify all anatomical studies investigating the variability in the formation of the brachial plexus. Data extracted consisted of demographic information, morphometric parameters, the arrangement of the brachial plexus at the level of the roots, trunks, divisions and cords and the relationship of the brachial plexus to the axillary artery and scalene muscles. The different configurations of the brachial plexus were put into a new classification, and the pooled prevalence of each case was calculated using a random effects model. A sub-analysis on age and geographical location was also performed. RESULTS: A total of 40 studies (3055 upper limbs) were included in the meta-analysis. The regular arrangement of roots forming trunks was identified in 84% (95% CI 79-89%) of cases. The overall prevalence of the prefixed and postfixed brachial plexus was 11% (95% CI 6-17%) and 1% (95% CI 0-1%), respectively and in less than 0.1% of cases the brachial plexus received a branch from both C4 and T2. For divisions forming cords, the regular arrangement was observed in 96% (95% CI 93-98%) of cases. Additional communicating branches between the components of the brachial plexus appeared in 5% (95% CI 3-7%) of cases. The relationship of the brachial plexus to the axillary artery and scalene muscles was considered regular in 96% (95% CI 89-100%) and 86% (95% CI 66-98%) of cases, respectively. Analysis of the morphometric parameters revealed the proportional consistency between the components forming the plexus during aging. CONCLUSIONS: Knowledge of anatomical variations of the brachial plexus is important for examinations and interventions in the lower neck and axilla. The variability was observed especially in the roots forming trunks, while divisions forming cords showed quite stable appearance. The results of this evidence-based review and meta-analysis can be applied in many different medical disciplines.

Absence of flexor digitorum profundus muscle and variation of flexor digitorum superficialis muscle in a little finger: two case reports.

PURPOSE: Knowledge of rare variants of the FDP is of high clinical importance for physicians examining patients for tendon lacerations and especially for hand surgeons operating tendon injuries. METHODS: During routine dissection at our Department of Anatomy both cases were observed. RESULTS: Variations of flexor digitorum superficialis and flexor digitorum profundus muscles of the little finger were observed in two cadavers. In both cases, the flexor digitorum profundus muscle for the little finger was absent. Moreover, in the first case, the flexor digitorum superficialis muscle for the little finger was hypoplastic and in the second case it featured variable insertion. CONCLUSION: There were found only four cases in previous literature describing absent flexor digitorum profundus tendon without any muscle attachment to the base of the distal phalanx. Furthermore, all previously described cases were observed in living patients. To our best knowledge, a case report in cadaver has yet not been reported and is of high importance for hand surgeons examining the hand for tendon injuries.