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At least 217 records · Page 12Linked to original sources
PubMed1986

Anatomical variations of the semilunar notch in elbow dislocations.

The anatomical relations of the semilunar notch of the ulna were studied in radiographs, taken in a strict lateral view, from 100 patients with elbow dislocations. The results were compared with those from a control group of 150 patients without dislocation or other radiographic pathology. We found that the coronoid process and an angle (a) formed between the axis of the ulna and a line going through the tip of the coronoid process and the tip of the olecranon were significantly smaller than those in the control group (P = 0.02). The central angle of the semilunar notch was significantly larger in the dislocation group than in the control group (P = 0.009). The smaller angle (a) and larger central angle in the dislocation group are a result of a lower coronoid process, but they are also due to the prominent tip of the olecranon. The results suggest that the dislocation mechanism is partly a hyperextension, with the tip of the olecranon as the pivot point.

Disease Susceptibility↗
PubMed1999

Anatomic variations in sensory innervation of the hand and digits.

Anatomic dissections under microscopic magnification were performed on 30 fresh cadaveric hands to depict the course and interconnections of the sensory nerves to the digits. The dissections included the median nerve, the ulnar nerve, the superficial branch of the radial nerve, the dorsal branch of the ulnar nerve, and the dorsal branch of the proper digital nerve. The communicating branches between the median and ulnar nerves in the palm were found in 20 of the 30 (67%) specimens. The dorsal branch of the proper digital nerve was found to arise at or proximal to the A1 pulley zone in 62% of the long digits, more proximally than previously reported. The dorsal sensory nerves (the terminal branch of radial or ulnar sensory nerves) extending to the nail bed area were found in 46% of the digits, thus confirming that sensory supply to the dorsum of the distal phalanx and nail bed also arises from the dorsal sensory nerves. Four types of palmar-dorsal interconnections, located in the middle of the proximal phalanx, were found in the digits but not in the thumb. The presence of these branches indicates dual innervation of the dorsal and palmar side of the distal areas of the digits. These anatomic findings may help hand surgeons interpret discrepancies in sensory loss after either dorsal or palmar injuries.

Adult↗
PubMed1988

Anatomical variation in the position of the proximal intercostal nerve.

Anatomical study of the proximal intercostal nerve in cadavers revealed three nerve forms, depending on the relation between the nerve and adjacent ribs. This was found in the classical subcostal position in 16.6%, in the midzone in 73% and in the inferior supracostal position in 10%.

Freezing↗
PubMed1998

Extracranial nerves in the posterior part of the head. Anatomic variations and their possible clinical significance.

STUDY DESIGN: An anatomic study of the peripheral nerves innervating the occipital region. OBJECTIVES: To study the topography of the extracranial occipital nerves, to define optimal locations for anesthetic nerve blockades, to provide guidelines to use with the suboccipital surgical approach, and to search for structures with putative pathogenetic implications in cases of unilateral headache. SUMMARY OF BACKGROUND DATA: There is little consensus in the literature concerning the sensory innervation of the scalp. Previous clinical and morphologic studies have not proven the existence of an entrapment mechanism in cases of unilateral head pain. Specific sites for anesthetic blockades have been defined only partly with reference to topographic landmarks. METHODS: The topography of the greater occipital (n = 20), the minor occipital (n = 19), and the greater auricular nerves (n = 17) was studied by dissection of 10 embalmed cadavers. Measurements of internerve distances and distances to defined landmarks were supplemented by drawings and photographs. RESULTS: A great variability in nerve topography was seen interindividually and intraindividually. The greater occipital nerve ascended between 5 mm and 28 mm from the midline along the intermastoid line. The minor occipital nerve was found between 32 mm and 90 mm from the midline along the same landmark. In most cases, both the greater occipital nerve and the minor occipital nerve pierced the aponeurosis after branching. Thirteen greater occipital nerves and eight minor occipital nerves also were embedded in this tissue. Twelve of the 20 greater occipital nerves formed a rich network around the occipital artery. However, anatomic structures with an imminent risk of causing entrapment were not observed. CONCLUSION: The results of this study suggest that optimal locations for blockade techniques should be reconsidered. The acquired knowledge concerning greater auricular and minor occipital nerves behind the sternocleidomastoid muscle may aid in preventing intraoperative injuries.

Female↗
PubMed1989

A cadaveric study of the anatomic variations of the recurrent motor branch of the median nerve.

Anatomic dissections were performed in 72 cadaveric upper extremities from 36 cadavers to determine the incidence of anomalous variations in the course of the median nerve and its branches. The classic recurrent motor branch anatomy was demonstrated in 86% of the dissections (62/72). Of the 10 variations noted (14% of all upper extremities), all were transretinacular branches that pierced the transverse carpal ligament 2 to 6 mm proximal to the distal edge. Of the six cadavers with anomalous branching, four (67%) had bilateral anomalies and two (33%) had unilateral branching.

Cadaver↗
PubMed1978

Analysis of the gross anatomical variations found in four cases of trisomy 13.

The variations and defects observed during detailed gross anatomical dissections of four cases of trisomy 13 are described. Emphasis is on the muscular system where previously undocumented variations, absences, and supernumerary elements were observed. A muscle phenotype which includes absence of palmaris longus, palmaris brevis, plantaris, and peroneus tertius, the presence of pectorodorsalis muscles and muscles from the central tendon of the diaphragm to the pericardium near the pulmonary veins, and variations in the extensor indicis, extensor carpi radialis longus and brevis, biceps, and suprahyoid muscles is discussed. The brain defects which include absent olfactory bulbs and tracts and hypoplastic commissures are compared to those defects seen in cases of alobar holoprosencephaly wherein severe defects of the ethmoid bone are concomitants. Previously well-documented defects of the viscera are included.

Abnormalities, Multiple↗
PubMed1980

Anatomic variations of the carotid bifurcation affecting doppler scan interpretation.

An anatomic variant for the position of the external carotid artery (ECA) at the carotid bifurcation was noted in 5.3 percent of patients studied by Doppler ultrasound and contrast angiography. The ECA is lateral to and posterior to the internal carotid artery (ICA) in these patients. Consideration of this important variant is mandatory for accurate ultrasound image correlation.

Angiography↗