Concrete use of the joint coordinate system for the quantification of articular rotations in the digital joints of the horse. (1/3)

A method is detailed allowing the computation of three-dimensional (3D) joint angles. Each joint of the equine digit is modelled as a sequence of three single axis rotary joints. The Joint Coordinate System was used; it involves a specific sequence of cardanic angles. The decomposition of the angles was chosen so that the three elementary angles coincide with the flexion/extension, passive abduction/adduction and lateral/medial rotations. The algorithms and kinematic procedures were described for the equine front digital joints. This method was tested in vitro on four forelimbs. For each limb, angle values were measured while the member was loaded by a press (from 500 to 6000 N). These tests were repeated while a wedge raised one part of the hoof (toe, heel, lateral and medial sides) in order to induce modifications of the angular patterns of the joints. This method allowed a precise quantitative determination of 3D joint movements. The modifications occurring with the wedges are clearly identified and confirm some previously published semi-quantitative observations. Moreover, this method provides a way to collect objective data on the functional anatomy of joints and could be used to study connective shoeing thoroughly. It may be directly applied to other species and may be used by researchers interested in discreet articular movements, especially occurring in other planes than the sagittal one.  (+info)

A veterinary digital anatomical database. (2/3)

This paper describes the Veterinary Digital Anatomical Database Project. The purpose of the project is to investigate the construction and use of digitally stored anatomical models. We will be discussing the overall project goals and the results to date. Digital anatomical models are 3 dimensional, solid model representations of normal anatomy. The digital representations are electronically stored and can be manipulated and displayed on a computer graphics workstation. A digital database of anatomical structures can be used in conjunction with gross dissection in teaching normal anatomy to first year students in the professional curriculum. The computer model gives students the opportunity to "discover" relationships between anatomical structures that may have been destroyed or may not be obvious in the gross dissection. By using a digital database, the student will have the ability to view and manipulate anatomical structures in ways that are not available through interactive video disk (IVD). IVD constrains the student to preselected views and sections stored on the disk.  (+info)

Lateral sellar compartment O.T. (cavernous sinus): history, anatomy, terminology. (3/3)

Claudios Galen (119-199 a.d.) dissected lower animals with parasellar carotid retia bathed in venous blood and transposed his findings to human anatomy. Andreas Vesalius (1514-1564) corrected most of Galen's errors but apparently never looked into this small, extradural compartment, nor, apparently, did Winslow (Exposition Anatomique de la Structure du Corps Humain. London: N. Prevast, 1734), who christened it the "cavernous sinus," (CS) presumably thinking that it would resemble the corpora cavernosa of the penis. Multiple surgical explorations, gross dissections, microscopic views, and vascular casts from early fetuses to an 81 year old have been examined and reviewed. The CS is not a dural sinus nor is it cavernous. The compartment is extradural, and the venous structures contained within consist of a greatly variable plexus of extremely thin-walled veins. The name, CS, is a barrier to the understanding of the structure and function of this extradural anatomical jewel box, which contains fat, myelinated and nonmyelinated nerves, arteries, and a plexus of veins. It is proposed that this name be changed, because it is inaccurate and misleading. The replacement should leave no doubt about its meaning. The lateral sellar compartment is descriptive and accurate. The veins within are a parasellar plexus.  (+info)