Laying Out Stirrups For Bending With and Without Deformities
Stirrups must be bent so that each upright is long enough to reach the ankle axis
Laying Out Stirrups For Bending With and Without Deformities To do so the correct length of the stirrup must be determined Measurements are then marked out on the stirrup to determine where to bend
Determining Stirrup Length Add the following measurements: Ankle axis to heel Sole thickness 1/8” bend allowance Multiply X 2 Add heel width 2 1/2” 3/8” 2 1/2” 3/8” 1/8” 3” X 2X 2 6” +2 3/4” total strirrup length 8 3/4 ” 2 3/4 Example
Laying Out Stirrup Without a Deformity Ankle Is In a Neutral Position
Laying Out Stirrup Without a Deformity Bisect the correctly sized stirrup through the ankle joint holes Measure the stirrup length between the hole centers Mark the midpoint of the stirrup on this line and centerpunch
Laying Out Stirrup Without a Deformity Mark out 1/2 the heel width on either side of center Measure out 1/8” from marks previously made and extend across the width. The stirrup will be bent on these lines Measure 1/2” down from center and centerpunch
Laying Out Stirrup With a Deformity Ankle Is In a Fixed Varus or Valgus Position
Laying Out Stirrup With Deformity When there is a fixed ankle deformity the stirrup uprights must be bent to unequal lengths This creates extra length for an upright to be more extensively contoured while maintaining a level joint axis
Laying Out Stirrup With Deformity Find the center of the stirrup as before Locate the measurement recorded when correcting the tracing (ankle center-heel center) Move the centerpoint 1/32” for each 1/4” of difference measured LM 3/4” ML
Laying Out Stirrup With Deformity The direction to move the centerpoint is determined by the deformity For a fixed varus deformity move the centerpoint medially LM 3/4” ML
Laying Out Stirrup With Deformity The direction to move the centerpoint is determined by the deformity For a fixed varus deformity move the centerpoint medially For a fixed valgus deformity move the centerpoint laterally LM 3/4” ML
Laying Out Stirrup With Deformity Continue to measure and mark out reference lines as before using the adjusted centermark ML
Laying Out Stirrup With Deformity Continue to measure and mark out reference lines as before using the adjusted centermark The stirrup is now ready to be bent up using the stirrup bending tool ML