F- CLINICAL ASPECTS OF SPINAL CORD INJURIES
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grounds, narrow solid tyres are preferable, while pneumatic tyres are more suitable on
soft ground or loose gravel. Non-porous inner tubes with efficient valves do not, as a
rule, require inflating more than two or three times a year.
The Ministry has previously provided wooden handrims which, however, proved to
be unsatisfactory because of easy splintering. They have been replaced by nylon-coated
steel. Moreover, aluminium alloy or plastic material is also suitable and may diminish
the weight. For tetraplegics with paralysis of the fingers, the adjustment of capstans
facilitates self-propelling. These patients need protection of the palm of their hands by a
soft leather appliance.
Castors should not be less than 7 in for the small front wheels and should run on
well sealed ball bearings. Castors of smaller diameter, especially the 5 in castor, are less
satisfactory, as they run into difficulties in negotiating carpets, loose rugs and other small
obstacles such as kerbs. We have always preferred the 8 in spoked castor, as fitted to the
Everest-Jennings and Vessa chairs, to the 7 in solid castor of the Ministry's chair, as the
latter in spite of its smaller size is heavier than the former.
The footrest of an all-purpose folding chair must be divided and able to be folded
upwards to facilitate getting into and out of the chair. Moreover, it should be adjustable
for height to suit individuals of varying sizes. Another advantage is to be able to swing
each section of the footrest outwards, which reduces the overall length of the footrest
and facilitates easy operation. To prevent the feet from slipping off the footrest in patients
with troublesome spasticity, special adjustments are necessary, consisting of a rim on the
back where the heel of the shoe rests in combination with a strap across the foot.
The backrest for paraplegics with lumbar and thoracic lesions should not be higher than
20-22 in, but the chair should be constructed to take a clip-on extension to increase the
height of the backrest which will give adequate support for patients with higher lesions.
Only tetraplegics above
C6/j
will need a higher backrest permanently, some of them even
with head support. Moreover, semi-reclining and reclining fixtures may be necessary to
be included in the construction of the chairs for these high lesions.
Armrests should be easily removable and well padded to ensure easy transfer to and
from the wheelchair, thus avoiding injury to the insensitive hips and buttocks. Only
certain types of distal spinal cord lesions without disturbance of sensibility, such as polios,
do not need detachable armrests. Armrests in which the upper front angle is cut out,
called 'desk5 or 'domestic' armrests, to allow the chair to be brought up close to a desk or
table, are in many cases preferable to the conventional straight armrests.
Wheelchairs for paraplegics and tetraplegics must be provided with a 4 in sorbo-
rubber cushion, which is most essential for preventing pressure sores. In recent years,
electrically controlled ripple cushions (Talley Surgical Instruments Ltd, London)
have been advocated for preventing pressure sores in paraplegics. These are justified
only in tetraplegics with paralysis of their triceps muscles, as all other spinal paralysed
can and should lift themselves at regular intervals to relieve pressure from their buttocks,
and counteract the development of contractures in hips and knees. The disadvantage of
such an electrically controlled ripple cushion is the increase of weight of the chair
through its battery.
Proper brakes are most essential components of hand-propelled wheelchairs. They
