Monday, July 4, 2011

Radial nerve rotation

Note 1: Maybe better word instead rotation should be "pronation", but I am not sure. Pronation means turning back of forearm to front (supposed that hand is down beside body). I have seen a pronation movement on medical software, but this movement seemed to me unlikely, because only forearm turned, but the humerus bone of upper arm did not rotated. So in this article I suppose that humerus bone rotates when you try to give hand in takate kote position.

Note 2: This article concerns only one vulnerable area, that is placed just under Deltoid muscle. Another vulnerable area for TK positions is placed just above elbow, and you can identify it from medical/anatomy pictures.

For those who are interested on radial nerve location (concerning TK safety):

Scheme of Humerus bone - size cca 2 cm:
sizes of the humerus

View on non rotated arm, radial nerve:
"back" view on the arm
"back" view on the arm
"back" view on the arm 2

My schemes to illustrate how much the radial nerve "position changes" during 45° rotation:

Test of rotation of "arm" / humerus bone:

I took a pole and paper and draw the lines on it. According scheme that I have. The red line is radial nerve (a piece of wire that I turned around according scheme).

Rotated and non rotated:

Back side of shoulder would be on left and elbow on right side. These two images I use to paste them in schema, so that the lines that I have drawn, would fix schema.
Area located between black lines no. 2 and no. 3 would seem to me safe for face-down suspension, but because the arm have to be rotated 45° in Takate Kote position, then the radial position moves more up, too close to rope.

Non rotated:



Non rotated - rotated:

The dangers area no. 1

Results of the test:

This demonstration should show how much the radial nerve "changes position". The area from black line no. 2 to no 3. is the area I still speak about.

If you see the vertical image - from the test is possible to see that the radial nerve appears to be close to right side.

The marked area black lines 2 - 3:
It seems to me that the lower 1/2 is dangerous for face down suspension. In the very edge of the Deltoid it could be really dangerous to have ropes for suspension. Then, in the upper 1/2 of marked area, it could be not so dangerous for F-D susp. but for safety reasons we should to place the ropes above this area.

For side suspension and back suspension the marked area in black lines 2 - 3 would be very dangerous area, where the ropes wouldn't be placed!

What danger?

The danger, that is related with incorrect rope placement or too tight tie, is the possibility that you can damage nerve. Too tight tie can cause nerve compression and this can hurt it. If we speak about radial nerve, which is placed in hand, then the injury causes impossibility to use toe or index finger. It can take few weeks to heal the nerve. To prevent this, we should place rope on body parts, which have muscles strong enough to prevent nerve damage. Rigger has to check ropes correct position and fixation or check it during the bondage play, if the tied person moves with ropes.

Sunday, July 3, 2011

Anatomy/Surgery images for those interested in bondage safety

These images are concerning vulnerable areas of limbs. It is good to be concerned in bondage safety. For example in Takate Kote ties we want to know which arteries we could restrain if we would tight the rope in incorrect place or too strong. Especially when some people are doing suspension they should know where the arteries and nerves are because it is possible to damage the nerves or to stop blood circulation in limbs. And because we don"t want anybody get hurt, we study anatomy and all the stuff around bondage safety.

If you click on thumbnails you open images that are hosted on this site - book Surgical Anatomy by Joseph Maclise.

You can find more on internet if you want to look, just search keywords like brachial, axillary, axillae, elbow, wrist. General problem when looking for anatomy images is that we would need special software that is not free, to get 3d images, animations etc, to see were nerves go from and to. Only good surgery images and software for surgery could provide that. Because for good orientation in the space man needs some points like muscles, arteries, veins.

Here is description of inner side of upper arm (not concertning radial nerve)
Upper arm: page

Upper arm & shoulder

Page Plate11
A. Subclavian vein;
   a, the axillary vein;
   a *, the basilic vein, having the internal cutaneous nerve lying on it.
B. Subclavian artery, lying on F, the first rib;
   b, the axillary artery;
  b *, the brachial artery, accompanied by the median nerve and venae comites.
C. Brachial plexus of nerves; c*, the median nerve.
S. Cephalic vein

This is Same page Plate 12 deeoer view to the same front area, when the arm is lifted & supported. You can see the Pectoralis minor (lesser Pectoral muscle: H,K) which is cut. Pectoralis minor lies under Pectoralis major (I), which is removed.

A. Axillary vein, cut and tied;
    a, the basilic vein, cut.
B. Axillary artery;
   b, brachial artery, in the upper part of its course, having h, the median nerve, lying rather to its outer side;
   b*, the artery in the lower part of its course, with the median nerve to its inner side.

Page Plate13

A. Axillary vein
  a - the common trunk of the venae comites, entering the axillary vein.
B. Axillary artery, crossed by one root of the median nerve;
   b - basilic vein,
   a- the axillary vein

Lower arm & upper arm above elbow: 

Page Plate15

H. Radial artery at its middle.
Upper arm inner side:
D. Cephalic vein, with the external cutaneous nerve (left, blue, big arc, outer side)
B. Basilic vein, with the internal cutaneous nerve. (right, blue, inner side)

Same page Plate 16

B. Basilic vein, cut.
C. Brachial artery.
D. Median nerve; d, the ulnar nerve.
F. Origin of radial artery.


page Plate 17:

B. Median nerve; its branches to the thumb and fin
D. Ulnar nerve; E e e, its continuation branching to the little and ring fingers

Same page Plate 18 
H. Ulnar nerve; h, superficial branches given to the fingers. I

Same page Plate 19
C. End of the radial nerve distributed over the back of the hand, to two of the fingers and the thumb.
D. Dorsal branch of the ulnar nerve supplying the back of the hand and the three ou

Legs - thighs

Page Plate27
f. The middle cutaneous nerve

d. A common venous trunk, formed by branches from the thigh and abdomen, and joining-- e
e. The saphenous vein.
g. Femoral lymphatic glands.
h. Superficial external iliac vein.
i. Superficial epigastric vein.

page plate28
M. The saphenous vein.N. A tributary vein coming from the fore part of the thigh.

same page Plate 29

I. The femoral vein.
K. The femoral artery.
O. The saphena vein.

page plate 30
N. The femoral artery; n, its profunda branch.
O. The femoral vein
P. The saphena vein

Schemes of veins and arteries
This image is from:

Other great sources:
Google translator - for translation of Latin names

Arteries, nerves and muscles of arm

Radiology site
many of images with descriptions here, but I miss upper arm and side views.

You can see there wonderful scans of arms, where also you see the important stuff of muscles (Deltoid, etc)

Also fascinating images (magnetic resonance) of circularity system:

And here high quality anatomy schemes: (sign up free).

Another good site with images of muscles right on bones:

Really Wonderful site - Magnetic resonance images of inside of human body