The Kolman PTB Casting Clamp
John L. Kolman, C.P.O. *
This successful device for taking PTB castings is unique and yet extremely simple to use. It produces a high quality cast with minimum distortion of the stump and requires vertually no modification of the cast. The pictures and the step by step procedure which follows illustrate the simplicity of the unit and its use.
No. 1 & 2
No. 1—Use a light cast sock applied to the amputee using a 1" elastic strap around the waist to maintain tension on the cast sock (see Fig. 1).
No. 2—Mark all bone prominences using an indelible pencil.
No. 3—Adjust casting clamp to the stump so that the popliteal pad is just lateral of the center of the stump or approximately parallel to the head of the fibula. Maintain the stump at an angle of about 30 degrees of flexion.
No. 4 (see Fig. 4)—Adjust the patellar buttons so that they fit on each side of the patellar tendon just distal of the patella.
No. 5—Press in anterior adjustable bar to obtain proper compression and set the locks straight. (See Fig. 3). Remove the clamp from the stump and mark the position of the AP adjustment so that it can be replaced in the same position after the cast has been wrapped.
No. 6—Take the cast using a moderately thin bandage so that it will not begin to set before the clamp is placed in position. Make sure that the cast is wrapped sufficiently above the patellar to insure good coverage in the popliteal area. A thin cast is all that is necessary and even distribution of the wrap is also desirable.
No. 7—Open the clamp and place it in position on the cast in the same position as it was during the test application. If your cast is relatively light, the new position of the AP bar will be within 1/4" of original mark.
No. 8—After the clamp is in place, continue to form the plaster cast to avoid any possibility of hollow spots.
No. 9—After the cast is set, remove the clamp. Mark it according to the normal PTB top shape and trim the cast to your line. When you trim, observe the position of the hamstrings and release accordingly. After the cast has been filled, cut the patellar tendon depression to intersect the top edge of the button marks. Do not go any deeper. No modification will be required in the popliteal area.
As you can see, casting technique is greatly simplified and will produce an excellent result.
The casting clamp is in production and will be available from Fluid Controls Inc., 623 South Central Avenue, Glendale, California.