POTT’S PARAPLEGIA ANWAR R. GUIRGUIS, CAIRo, UNITED ARAB REPUBLIC From the Orthopaedic Hospital, Helwan, Cairo The Orthopaedic Hospital at Helwan lies about fifteen miles from Cairo and contains 365 beds, almost entirely devoted to the care of patients with tuberculosis of bones and joints. They are admitted either from the weekly out-patient clinic or referred from the anti-tuberculosis clinics and the orthopaedic surgeons in Upper Egypt. Although some patients can be supervised at Heiwan afterwards, most return to their own towns and villages and cannot be seen for review. Improvements in public health and in nutrition, and the development of anti-tuberculous drugs have produced a decline in the incidence of tuberculosis of bones and joints, but wherever there are patients suffering from spinal tuberculosis, there will be cases of paraplegia. The risk of paralysis developing is related to many factors, of which the following appear to be the most important. Inadequate care-Tuberculosis of the spine is a serious disease and, once diagnosed or even suspected, it should be treated by a surgeon with special experience in this type of work who has access to a centre devoted to the management of these patients. This is of particular importance in communities in which tuberculosis is not eradicated or under control, and in which the opportunities for domiciliary supervision are limited. Late diagnosis-The detection of tuberculosis of the spine in the early stages of the disease is often difficult because the characteristic radiological changes may not be present. It is better to make a provisional diagnosis of tuberculosis by excluding other spinal infections than to await the appearance of bone destruction, thus preventing patients from first presenting with paraplegia. Incorrect freatment-Adequate chemotherapy for the spinal lesion is necessary from the time of diagnosis. At least two antibiotics should be used at the same time, and every effort must be made to ensure that the patients actually take the drugs prescribed. In the presence of active spinal disease rest in bed is necessary, and when extensive bone destruction has occurred early spinal fusion, preferably from the front, may be necessary to stabilise the spine and to prevent pressure upon the cord. Premature cessation of treatment-Antibiotic treatment is necessary for at least six months after the spinal lesion appears healed. Failure to maintain treatment for an adequate time carries a grave risk of reactivation of the disease, and with it the risk of paraplegia. Development of drug resistance-It is often impossible to obtain material from a cold abscess or from the spine itself for culture, but any organism which can be grown should be tested for sensitivity to the standard antibiotics. Tubercle bacilli resistant to streptomycin and isoniazid are not common, but are prone to occur in patients who have previously received treatment with a single drug. Level of disease-Compression of the spinal cord may occur at any level from the foramen magnum to the upper lumbar region, but is most common in the thoracic spine. Here the spinal canal is narrow, and the cord occupies most of it, so that even a small abscess or sequestrum may produce cord pressure. In the cervical region infected material can track sideways along the fascial planes, and in the lumbar region along the psoas sheath to the groin, but in the thoracic region pus tends to collect beneath the anterior and posterior longitudinal ligaments under tension, and to spread upwards and downwards to form a paravertebral abscess. 658 THE JOURNAL OF BONE AND JOINT SURGERY
Transcript
POTT’S PARAPLEGIA
ANWAR R. GUIRGUIS, CAIRo, UNITED ARAB REPUBLIC
From the Orthopaedic Hospital, Helwan, Cairo
The Orthopaedic Hospital at Helwan lies about fifteen miles from Cairo and contains
365 beds, almost entirely devoted to the care of patients with tuberculosis of bones and joints.
They are admitted either from the weekly out-patient clinic or referred from the anti-tuberculosis
clinics and the orthopaedic surgeons in Upper Egypt. Although some patients can be supervised
at Heiwan afterwards, most return to their own towns and villages and cannot be seen for
review.
Improvements in public health and in nutrition, and the development of anti-tuberculous
drugs have produced a decline in the incidence of tuberculosis of bones and joints, but wherever
there are patients suffering from spinal tuberculosis, there will be cases of paraplegia. The risk
of paralysis developing is related to many factors, of which the following appear to be the
most important.
Inadequate care-Tuberculosis of the spine is a serious disease and, once diagnosed or even
suspected, it should be treated by a surgeon with special experience in this type of work who
has access to a centre devoted to the management of these patients. This is of particular
importance in communities in which tuberculosis is not eradicated or under control, and in
which the opportunities for domiciliary supervision are limited.
Late diagnosis-The detection of tuberculosis of the spine in the early stages of the disease
is often difficult because the characteristic radiological changes may not be present. It is
better to make a provisional diagnosis of tuberculosis by excluding other spinal infections
than to await the appearance of bone destruction, thus preventing patients from first presenting
with paraplegia.
Incorrect freatment-Adequate chemotherapy for the spinal lesion is necessary from the time
of diagnosis. At least two antibiotics should be used at the same time, and every effort must
be made to ensure that the patients actually take the drugs prescribed. In the presence of
active spinal disease rest in bed is necessary, and when extensive bone destruction has occurred
early spinal fusion, preferably from the front, may be necessary to stabilise the spine and to
prevent pressure upon the cord.
Premature cessation of treatment-Antibiotic treatment is necessary for at least six months
after the spinal lesion appears healed. Failure to maintain treatment for an adequate time
carries a grave risk of reactivation of the disease, and with it the risk of paraplegia.
Development of drug resistance-It is often impossible to obtain material from a cold abscess
or from the spine itself for culture, but any organism which can be grown should be tested
for sensitivity to the standard antibiotics. Tubercle bacilli resistant to streptomycin and
isoniazid are not common, but are prone to occur in patients who have previously received
treatment with a single drug.
Level of disease-Compression of the spinal cord may occur at any level from the foramen
magnum to the upper lumbar region, but is most common in the thoracic spine. Here the
spinal canal is narrow, and the cord occupies most of it, so that even a small abscess or
sequestrum may produce cord pressure. In the cervical region infected material can track
sideways along the fascial planes, and in the lumbar region along the psoas sheath to the
groin, but in the thoracic region pus tends to collect beneath the anterior and posterior
longitudinal ligaments under tension, and to spread upwards and downwards to form a
paravertebral abscess.
658 THE JOURNAL OF BONE AND JOINT SURGERY
Total number of discharges (or deaths) . . . 653
Cervical tuberculosis . . . 13
Thoracic tuberculosis . . . . 210
Lumbar tuberculosis . . . . . 86
Combined thoraco-lumbar tuberculosis . . . 11
Pott’s paraplegia . . . . . . . 78
NUMBER
o�PATIENTS
GRADE AT ONSET I III IV
POTT’S PARAPLEGIA 659
VOL. 49 B, NO. 4, NOVEMBER 1967
CLINICAL EXPERIENCE WITH POTT’S PARAPLEGIA
From July 1964 to August 1965, 653 patients completed their treatment in this hospital
or died there, and of this total 398 were suffering from spinal tuberculosis (Table 1). There
were seventy-eight patients with Pott’s paraplegia, of whom thirty were treated surgically.
TABLE I
PATIENTS DISCHARGED FROM THE ORTHOPAEDIC HOSPITAL, HELWAN,
FROM JULY 1964 TO AUGUST 1965
With greater experience we would now operate on a higher proportion. The remainder do
not represent true controls-no two cases can be directly comparable. They have, nevertheless,
been matched to some extent against the patients treated by operative methods ; they appeared
to make slower progress and a much less complete recovery.
At operation the affected area was exposed by the antero-lateral route, but some patients
had previously had other procedures which had failed to produce any improvement. Although
the main object of this operation must be to relieve
cord pressure, when the spine was unstable or the
disease very extensive an attempt was also made to
fuse the spine. The extent of the bony disease and
of the paraplegia, and the results achieved, are
indicated in Figure 1. It can be seen that there was
one death. This was in a boy of eleven with disease
of the fourth and fifth thoracic vertebrae, and
tuberculosis of the right hip. There was shock after
operation, at which no blood transfusion was given,
and the boy died an hour and a half later. Most of
the patients were aged between twenty and thirty-
five; the youngest was four and the oldest sixty
(Fig. 2).
Of the twenty-nine patients who survived
the operation, fourteen were discharged with the
disease in the spine under control and a complete
cure of the paraplegia, and three showed no signifi-
cant improvement, apart from the healing of bed-
sores. In order to study the changes in the rest, the
following classification of paraplegia was used:
Grade I-exaggerated reflexes but able to walk
unaided; Grade Il-marked altered gait needing
external support; Grade Ill-bedridden; and
Grade IV-total paraplegia.
It will be seen from Figure 1 that twenty
FIG. 1 patients achieved a satisfactory return of muscleFinal grade of paraplegia related to grade at onset. power and control, although some failed to obtain
FIG. 2
Age of onset of paraplegia in patients treated by operation.
660 A. R. GUIRGUIS
THE JOURNAL OF BONE AND JOINT SURGERY
complete control of the sphincters and should not, therefore, be classified as cured. The poor
results were in patients who were bedridden at the time ofonset, and no patient with a complete
flaccid paralysis improved. In considering these results it must be remembered that the
follow-up was short, and that some improvement might still be expected in patients whose
recovery was still incomplete. Those who showed no gain in the level of paraplegia often
achieved something in the healing of bed-sores, improvement of micturition or the relief of
painful spasms, a gain which, even in those who remained confined to their beds, was often
of great value.
Relevant details of the thirty patients subjected to operation are summarised in Table II.
ILLUSTRATIVE CASE REPORTS
Case 7-A woman of twenty-five had disease of the eighth thoracic vertebra (Figs. 3 and 4)
present for nine months, and paraplegia for six weeks. A previous costo-transversectomy to
drain an abscess had improved her for a short time but the paraplegia had then progressed to
Grade III. A right antero-lateral decompression of the eighth and ninth thoracic vertebrae
was done with removal of granulomatous tissue and sequestra from in front of the cord.
Cancellous bone chips were packed into the cavity and the patient obtained a complete cure
of the paraplegia.
Case 16-A woman of fifty with disease of the seventh, eighth and ninth thoracic vertebrae,
present for two years, had had a cold abscess incised followed by a persistent sinus and
thereafter a paraplegia (Grade III). The radiographs (Figs. 5 and 6) showed the sinus injected
with lipiodol, and a left antero-lateral decompression of the seventh, eighth and ninth thoracic
vertebrae revealed tough, greyish membrane around the cord. The dura was healthy; a rib
graft was put in. The paraplegia was almost cured and the disease controlled. The grafts
fused solidly and the patient was discharged after seven months.
Case 29-A man of seventeen had disease of the eleventh and twelfth thoracic vertebrae and
first lumbar vertebra, present for one and a half years, and a paraplegia (Grade III) for three
months, which had been precipitated by a fall from a height. The radiograph (Fig. 7)
showed severe collapse of the twelfth thoracic vertebra which was almost completely destroyed,
but the posterior neural arch was intact. A left antero-lateral decompression of the eleventh
and twelfth thoracic vertebrae allowed removal of diseased bone from in front of the canal
which was widened, and a posterior fusion with a tibial graft from the tenth thoracic vertebra to
the first lumbar vertebra was done. The paraplegia improved but the patient remained spastic.
CLASSWICATION OF POTF’S PARAPLEGIA
It is convenient to consider two groups of paraplegics, a group in which the disease is
reversible, and a group in which the changes are permanent. It must be accepted, however,
that untreated paraplegia may progress from the reversible to the irreversible stage.
VOL. 49 B, NO. 4, NOVEMBER 1967
POTr’S PARAPLEGIA 661
TABLE II
CLINICAL DETAILS OF THIRTY PATIENTS WITH PARAPLEGIA SUBJECTED TO ANTERO-LATERAL DECOMPRESSION
number � (y��s)Sex �i�:1�5:�
Additional details
1 30 Female T. 2-4 1 month Cured
2 6 Male T. 5-7 Cured
3 25 Female T. 5-6 Cured I Rib-graft fusion
4 35 Female T. 9-10 3 months Much improved
5 30 Male T. 9-11 3 months Improved
6 25 Female T. 2-3 Improved
7 25 Female T. 8 6 weeks Cured Previous costo-transversectomy:
8 60 Male T. 5-6 2 weeks Cured
9 30 Female T. 9-12 3 months CuredPrevious costo-transversectomy:
Reversible paraplegia-The causes are as follows. 1) Oedema of the cord from circulatory
changes as a result of the spinal lesion. These patients have a mild paraparesis with absence
of sphincteric disturbance. They improve rapidly within four weeks of admission to hospital
and adequate treatment, and operation is seldom necessary. They represent about 10 per cent
ofthe paraplegics received (five out of sixty patients, one of whom was treated surgically because
of radiographic evidence of a sequestrum which it was thought might be pressing upon the
cord). 2) Compression by a collection of fluid or semi-fluid material under tension.
Radiologically it appears as a tense paravertebral or prevertebral abscess. 3) Compression
from sequestra or remnants of a disc. 4) Compression from collapsed vertebrae. Paraplegia
can develop in a short time if diseased vertebrae are not supported, or gradually if the support
is not adequate during the treatment. This can account for some of the cases previously
classified as paraplegia of late onset but really of the early onset type.
Irreversible paraplegia-It is understood that paraplegia that could recover might, if neglected,
change to irreversible paraplegia. Irreversible paraplegia usually starts late during the active
stage of the disease, but sometimes it occurs many years after healing of the disease when
the patient is considered cured. It is associated with degeneration of the spinal cord and
may be secondary to vascular changes. It is found not only in patients with a severe gibbus
who are left untreated for a long period, but also in those in whom the disease has been
arrested for a long time and who have been rehabilitated. It often occurs in patients doing
sedentary work, who bend their heads, as in watch repairing, because this rubs the cord
against the apex of the gibbus, which is increased by the flexion of the head and of the hips.
This must be remembered when patients with a severe gibbus are to be rehabilitated.
On four occasions operation revealed nothing to account for compression. On exploration
a tough membrane, greyish white to pink in colour, was found closely surrounding the cord
and extending beyond the diseased area. It was not adherent to the dura or to the bony
canal, and could be stripped off leaving a healthy dura. These patients showed a varying
degree of recovery, and two of them may be considered to have made a complete recovery.
In these patients there was neither radiological evidence nor changes found at operation to
account for the paraplegia. Another two patients with membrane formation were found in
whom there were other causes which could account for compression. None of these six
patients had a clear abscess shadow but all had chronic paraplegia.* The nature and the role
of this membrane in compressing the cord is still under investigation.
TIMING OF OPERATIVE DECOMPRESSION
Opinions differ about how long the patient should be kept under conservative treatment
before operation is indicated. We consider that the best time for intervention is two weeks
after admission, except in the rare cases when decompression is considered urgent. During
this time the patient can be investigated fully, his general condition can be improved to
withstand a major operation, and chemotherapy can be adequately supervised. During this
time those patients with paraparesis caused by oedema may start to improve, and an unnecessary
operation may be avoided. It is inadvisable to wait for more than two weeks for the
following reasons. I) Tuberculosis is a chronic process and, with conservative treatment,
the relief of compression occurs by absorption of the compressing material which at best will
take months. There is always a long lag between the cessation of activity and the relief or
diminution of compression. During this time there are changes going on in the affected limbs
such as wasting of muscles, contractures and painful spontaneous spasms which are difficult
to relieve. To prevent these changes takes time and experienced nursing together with
* A patient is considered to have chronic paraplegia when it has been present for three months with no sign of
improvement or when at the first attendance paraplegia has been present for three months with no propertreatment.
THE JOURNAL OF BONE AND JOINT SURGERY
FIG. 3 FIG. 4
Case 7-Paraplegia associated with a tense paravertebral abscess. Treated initially by costo-transversectomywhich failed to give permanent improvement. Complete cure followed antero-lateral decompression.
POTT’S PARAPLEGIA 663
VOL. 49 B, NO. 4, NOVEMBER 1967
continuous medical supervision. 2) The structure of the cord is so delicate and any degenerative
change so constantly irreversible that long continued compression is most undesirable. It is
better to operate on some patients who might recover without operation than to run the risk
of permanent irrecoverable damage to the cord because of hesitation or delay. 3) Pathological
examination of the spinal vessels from two patients with neglected paraplegia showed chronic
degenerative lesions with narrowing of the lumen. Both patients, who were women aged
twenty-three and thirty-six years, entered hospital in the terminal stage with ulcers and bed-
sores, and died shortly afterwards. There was no evidence of generalised vascular degenerative
disease. Although these changes may be secondary to the tuberculous lesion itself, there is
nevertheless a possibility that they are caused by prolonged compression. These vascular
changes can account, firstly, for some failures to make a complete recovery after apparently
successful decompression operations; and secondly, for some patients with paraplegia of
late onset in whom degeneration of the tracts occurred. They may in fact be caused by
vascular degeneration of the spinal vessels because of untimely relief of compression. 4) It is
sometimes stated that patients with tense abscess shadows benefit from conservative treatment
but on two occasions patients who had undergone costo-transversectomy for relief of tense
abscesses had to have further operations and antero-lateral decompression, at which other
causes of compression were found (Figs. 3 and 4). These two patients did not show any
radiological cause for compression other than a tense abscess shadow.
The advantages of early operation for these patients are many. Whereas with conservative
treatment at least twelve months in hospital is needed, surgery can shorten this time to less
than half. Comparing the results of treatment in sixty patients, half treated surgically and half
conservatively, we found at the time of discharge that sphincter control, the grade of recovery
of motor power, the gait and the tendon jerks in those treated by operation indicated a far
better clinical result, obtained in a far shorter time.
664 A. R. GUIRGUIS
Attacking the lesion directly gives a better chance for the antibiotics to reach the diseased
area, lessens the risk of drug resistance, and also shortens the time in which chemotherapy
is needed. It has also the advantage that anterior fusion of the spine can be done at the same
time.ANTERO-LATERAL DECOMPRESSION
This has become the standard procedure for the relief of spinal cord compression in
Pott’s disease. The operation has a number of risks which we have attempted to eliminate
in the following ways.
Weakening of the vertebral column-Little loss of strength in fact occurs, provided the facets
are not disturbed. The parts removed are diseased and afford no mechanical support. Little
ofthe vertebral pedicle need be removed ifthe approach is extended well into the vertebral body.
Vertebral collapse after operation-This can be prevented either by anterior fusion or by rigid
external support. None of our patients has, in fact, developed this complication, and we no
longer rely on a support in the immediate period after operation. Each patient spends
at least a month in bed and is allowed up wearing a support or a plaster jacket as soon after
this as the paraplegia allows, remaining ambulant in the hospital for another month before
discharge. Most patients come from distant towns in Upper Egypt, and although they are
advised to wear the support for six months after discharge, many of them discard it owing
to the heat and refuse even a light support. In spite of this, those who returned after six
months for reassessment did not show any increase of deformity or reactivation of disease.
Tuberculous meningitis-This is a theoretical risk only. Not a single case can be found in the
literature, neither has it occurred in any of our patients. In two patients the dura was opened
accidentally without harm, and in two others lumbar puncture was done in the active stage of
the disease without incident. Under adequate chemotherapy this complication need not be
feared.
Tuberculous empyema-The extra-pleural approach prevents this complication. On three
occasions the pleura was accidentally opened, but no infection of the pleura occurred ; only on
one occasion was there a haemothorax which required aspiration before resolving. Sometimes
it is very difficult to expose the diseased area because of adhesions between the pleura and
the extra-pleural tissues. This can be overcome by stripping the periosteum from the side of
the vertebral bodies by sharp dissection.
The trans-pleural approach gives a better exposure but has a number of disadvantages.
1) It cannot be used in the presence of an abscess cavity with frank pus and infected material.
2) When the disease is active, especially when it is extensive, the pleura is friable and may
be almost impossible to close satisfactorily. 3) In advanced paraplegia with bed-sores it is
inadvisable owing to the general condition. 4) It cannot be used in patients with combined
skeletal and pulmonary tuberculosis.
Injuries to intercostal nerves-In the earlier cases we cut these nerves; some of the patients
suffered severe neuralgic pains, others had weakness of the flank muscles when we cut the
lower intercostals. Now these nerves are used as a guide, and every effort is made to preserve
them. However, sometimes because of dense adhesions this is not possible, especially in
patients on whom operations have been done before.
Injury to the cord-Increase in paraparesis, or complete paraplegia after operation, may be
caused by the following: Concussion-There were two patients with cord concussion after
operation; both made a complete and rapid recovery. Oedema of the cord-This may occur
either as a complication of the operation itself, and will then subside within a week, or as a
result of secondary infection of the wound. The latter occurred in one patient, and was
associated with an increase in the paraplegia one week after operation which subsided as soon
as the infection was controlled. Pressure by haematorna-Increasing pressure on the cord
from a haematoma was seen in one patient who improved after evacuation of the haematoma.
It is usually advisable to drain the wound after operation, preferably by a vacuum drain.
THE JOURNAL OF BONE AND JOINT SURGERY
1r�
FIG. 5 FIG. 6
Case 16-Paraplegia associated with a cold abscess and a discharging sinus but no significant bone destruction.The sinus was injected with opaque fluid which indicated the region of the bone infection and, at antero-lateral
decompression, the cause of the compression was found to be membrane formation.
POTT’S PARAPLEGIA 665
VOL. 49 B, NO. 4, NOVEMBER 1967
The risk of haematoma formation is increased with hypotensive anaesthesia, and every
precaution must be taken against reactionary bleeding. Organic injury to the cord-This can
occur, but was not seen in this series. The spinal cord is, however, very sensitive to pressure,
and great care is necessary to avoid injuring it.
INDICATIONS FOR ANTERO-LATERAL DECOMPRESSION
Although it has been our practice to explore the spinal cord soon after admission in
patients with Pott’s paraplegia, some can undoubtedly be managed conservatively, although
their progress is often slow. In those in whom the prognosis with conservative treatment is
bad, operation is essential. The main indications for this are as follows. 1) Compression of
the cord but with no tense abscess shadow to be seen radiologically. 2) When the cause can
be suspected radiologically to be sequestra or the posterior border of a collapsed vertebra,
especially when the canal appears narrow or acutely angulated. 3) In patients with no
improvement after decompression of a tense abscess by other means such as aspiration or
costo-transversectomy. After such simple decompression improvement in the paraparesis
must be expected within four weeks, otherwise another cause of compression must be sought.
Compression by a tense abscess produces no more than heaviness in the lower limbs; altered
gait; exaggerated reflexes; mild sphincteric changes mainly in the form of precipitancy;
bouts of diarrhoea without any apparent cause; and mild wasting of muscles. Both limbs
are usually equally affected, and spontaneous painful spasms are not a marked feature.
In patients with advanced paraplegia, with complete incontinence, especially when one side
FIG. 7
Case 29-Gross destruction of the eleventh and twelfththoracic, and first lumbar vertebrae associated withsevere paraplegia, which was improved a little byantero-lateral decompression at the first two levels.
666 A. R. GUIRGUIS
THE JOURNAL OF BONE AND JOINT SURGERY
is more affected than the other side-even if a tense abscess shadow is evident radiologically-
compression by other more resistant causes must be suspected. The advanced paraplegia
improved by simple evacuation of the abscess either recurs or is incompletely relieved.
For this antero-lateral decompression is indicated and gives good results. 4) For neglected
paraplegia this form of decompression is the
only hope. No matter how long-standing
the paraplegia is, and before any attempt is
made to correct limb deformities, it is ad-
visable to decompress the cord, and often
also to stabilise the spine by fusion. 5) When
there is no radiological cause of compres-
sion, exploration of the cord at the suggested
site of compression may show a tense mem-
brane around the dura or a sequestrum
which cannot be seen radiologically (Figs.
5 and 6). 6) When there is a severe gibbus
with narrowing of the canal at its apex.
Widening the canal and giving the cord more
space gives considerable improvement in the
paraplegia and saves the tracts of the cord
from further degenerative changes (Fig. 7).
7) The hopeless group in Seddon’s classifi-
cation of prognosis of paraplegia. In our
series four patients had a spastic paraplegia
in flexion with bed-sores. After operation
the bed-sores healed rapidly. Two patients
obtained complete control of their sphincters
and improved to the extent to be considered
fit for discharge and independent life with-
out any external help. The other two patients
were helped considerably : their sphincter control was improved though precipitancy remained,
the painful spasms were abolished and physiotherapy and rehabilitation could be started. Of
another two patients with flaccid paraplegia, one had improvement in his bed-sores and general
condition while the other was unchanged after two months.
EXTRA-PLEURAL APPROACH
Although the transpleural approach is claimed to give a better exposure and fewer
complications, we prefer the extra-pleural route mainly because the risk of a tuberculous
empyema is absent. We are now meeting an increasing number of patients with infection by
organisms resistant to the standard antibiotics, which cannot be detected until weeks after
the operation has been done. Although contamination of the pleura cannot always be avoided
by an extra-pleural approach, care can make it negligible. This approach exposes the back of
the affected vertebrae better so that the greater the kyphotic deformity the easier the operation
becomes.
DECOMPRESSION BY LAMINECTOMY
This operation is rarely indicated in Pott’s paraplegia. It destroys the healthy part of
the neural arch and further weakens the vertebral column. This weakness cannot be overcome
by performing a posterior spinal fusion. In 80 per cent of the patients reaching this hospital
clinical and radiological examination showed that the compression lay on the anterior surface
of the cord. By decompressing these patients posteriorly, the kinking of the spinal cord is
POTT’S PARAPLEGIA 667
made more acute. The posterior approach does not permit the lesion to be attacked directly,
nor does it allow anterior fusion to be done at the same time; the end-results of this operation
are therefore poor.
The two main indications for laminectomy are, firstly, the rare cases of spinal tumour
syndrome, in which the compression starts beneath the posterior ligament, with the neurological
signs preceding the radiological changes; and, secondly, in pathological dislocation, from
destruction of the vertebral arch, causing cord compression. Here treatment is by laminectomy
and spinal fusion.
SUMMARY
1. A comparison of the results of sixty patients with Pott’s paraplegia, half operated upon
and half treated conservatively, showed that better results were achieved in a much shorter
time in those treated surgically.
2. Extra-pleural antero-lateral decompression is the operation of choice in cases of Pott’s
paraplegia.
3. The operation should be done as soon as the general condition of the patient allows,
and should not be left until the disease is quiescent.
4. The greatest improvement is found in those patients who are still ambulant.
5. Although the gain in patients with complete paraplegia may be small, relief from painful
flexor spasms and the healing of bed-sores often justify surgical treatment.
6. Fusion of the vertebral bodies can be carried out at the same sitting using healthy ribs
and sometimes cancellous bone, with satisfactory results.
I wish to give my thanks to Mr P. A. Ring for his encouragement and advice, and to Mrs Angela Howardfor her assistance.
