Fig. 30.
Combined suspension for short stumps.
Fig. 28.—Complete appliance.
Fig. 29 and 30 show the value of a flexion pivot between the hip piece and the pelvic plate. If there is no such pivot, the T piece undoubtedly rotates upon the belt, but not to a sufficient extent to prevent the thigh piece in rising and pinching the abdominal wall (Fig. 29). If there is a double joint the hip piece becomes oblique, thrusting the thigh piece forward and allowing the patient to sit erect (Fig. 30).
In these cases also, to prevent the stump escaping from the bucket when the hip is flexed, the front of the thigh piece is carried as high as possible; but if the appliance is furnished with a metal T piece, such as has been described ([Fig. 29], see also [Fig. 23]), then this raised border prevents flexion of the hip by coming in contact with the abdominal wall when the patient sits down. This difficulty can be got over by making the top of the T piece movable; when the patient sits down the vertical piece of the T becomes oblique, the thigh piece comes forward, allows the stump to escape a little way and no longer presses against the abdominal wall ([Fig. 30]).
The belt may also be replaced by a leather corselet, having fixed to it the hip piece that we have just described.
The braces by themselves are a poor method of attachment for a short stump.
In the sitting position the stump easily escapes from the bucket.
When the patient is standing the stump remains abducted, whilst the apparatus, as the result of its own weight hangs vertically, in this swaying position the lower extremity of the stump presses against the outer side of the bucket, whilst the inner edge of the bucket cuts into the flesh at the top of the thigh.