A composite 3D printed model of the midcarpal joint.

Three-dimensional (3D) printing has recently been developed as a resource for teaching human anatomy through the accurate reproduction of anatomical specimens. Using a composite 3D printed model with the incorporation of metal and magnets, we were able to demonstrate and analyse movements at the midcarpal joint during the 'dart thrower's motion', which is an important motion in daily activities involving the use of the hand. The hand component with the distal row of carpal bones was subjected to flexion and extension at the midcarpal joint and observed for simultaneous abduction/adduction.

Medial pretarsal adipose tissue in the Asian upper eyelid.

Purpose: To report the presence of a localized pad of adipose tissue in the medial anterior tarsal surface of the Asian upper eyelid.

Methods: Clinicohistologic case series. The presence and extent of a localized pad of adipose tissue in the medial pretarsal area were documented: 1) intraoperatively for 51 consecutive upper eyelid surgeries; and 2) in the histologic study of 10 cadaveric upper eyelid specimens.

The cervical sympathetic trunk--a new hypothesis.

There is a sympathetic ganglion, in relation to most if not all thoracic and lumbar segments whereas there are only 3 or 4 sympathetic ganglia in the cervical region. Thus it may be inferred that sympathetic ganglia are not directly related to spinal nerves. Therefore, the hypothesis is put forward that sympathetic ganglia are associated chiefly with intersegmental vessels such as the intercostal and lumbar arteries and that the differences seen in the neck region are due to the disappearance of most of the cervical intersegmental arteries and the subsequent modifications that follow during development.