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Anconeus Quintus
See Triceps Brachii
Variation archive
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See Triceps Brachii
Adductor brevis is frequently divided into two or three parts. It may be inseparable from adductor brevis. Syn.: m. adductor femoris brevis; adductor triceps, caput brevis or secundum.
See Trapezius
See Latissimus dorsi.
See Obliquus internus (Internal oblique)
See Abductor pollicis brevis
See Scalenus anterior or Anterior scalene
See Flexor digitorum superficialis (Sublimis)
See Flexor hallucis longus
See Flexor digitorum profundus
See Abductor digiti minimi
See Triceps brachii
See Abductor pollicis longus
Variations in the muscles of the thumb have been reported to occur in one of every six subjects dissected. The most common variations occur in the long abductor and consist of an extensive cleavage of its tendon, or even the whole muscle, into separate parts. The belly of the muscle may be doubled. The long abductor may be reduced to a small slip arising only from the radius. The abductor pollicis longus may also arise from both the ulna and the mediolateral aspect of the radius.
This muscle is small and arises from the lateral tubercle of the calcaneus and inserts onto the tuberosity of the fifth metatarsal bone. Reference Wood, J. (1864) On some varieties in human myology. Proc. Roy. Soc. Lond. B 13:299-303.
See abductor digiti minimi (manus).
This is a rare muscle that arises from the lateral process of the tuber calcanei and inserts onto the lateral surface of the base of the proximal phalanx of the little toe. See m. abductor digiti minimi (pedis).
Radiographs of the dorsal spine of a 3 year old female, showing absence of the posterior arches of D4-D7 (T4-T7), with marked widening of the spinal canal and multiple hemivertebrae involving the bodies of D6, 7 and 8 (T6-T8). Courtesy of Dr. Rafic Melhem, Dept. of Radiology, American University of Beirut, Beirut, Lebanon, May, 1980.
The usual grouping formula of 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal vertebrae is found in only about 20% of individuals studied. The cervical region is reported to be the most constant, the coccygeal the most variable. The number of elements of the vertebral column has been reported to vary between 32 and 35. Addition to a group is frequently seen, which occurs through the reduction in number of vertebrae of an adjacent group, the total number being unchanged. In this variation, the vertebra added is usually intermediate in form between the adjacent groups.
The body of the first thoracic vertebra may bear, on one or both sides, two costal pits resembling the usual thoracic type. The articulation of the head of the first rib is completed by a costal pit on the body of the seventh cervical vertebra. In rare cases the first thoracic rib may be rudimentary and similar in appearance to cervical ribs. The body of the second thoracic vertebra usually exhibits an identifying tubercle marking the attachment of a fasciculus of the medial portion of the longus colli muscle (Krmpotic).