The lever may be round or flat to suit different cases. Another mode of using the scamnum was to raise two posts at the middle of the sides, and to insert into them a transverse bar like the step of a ladder, to act as a horizontal perineal bar.
[Figure 10] shows the machine constructed from this description by Littré.
A figure of the machine, by Vidius, is somewhat different, ([Fig. 11]) square holes taking the place of the longitudinal grooves described by Hippocrates.
I shall now proceed to give a few descriptions of actual applications of the machine to reduction of different dislocations, which, it is hoped, will be readily understood by the aid of the accompanying figures, which are mainly taken from drawings by Vidius in illustration of a chapter by Heliodorus. One cannot help thinking that this machine must originally have given the idea for the instrument of torture known as the rack. This was well known in the time of Cicero.
Celsus says that the scamnum was quite powerful enough to produce rupture of the muscles.
[Fig. 12] shows the machine in use for dislocation forwards of the astragalus. Extension and counterextension are being made by thongs fastened below the knee and above the ankle.
[Fig. 13] shows an attempt at reduction of the spine. Extension is being made below the seat of the lesion by a thong passed round the abdomen above the crest of the pelvis, while counterextension is maintained by a thong passed under the armpits.
The operator’s assistant is levering down the gibbosity with a flat board used as a lever.
[Fig. 14] shows the reduction of a dislocated elbow. The forearm is pulled down by a thong passed over its middle, while counterextension is maintained by thongs attached to the humerus and the forearm near the wrist.