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TALECTOMY FOR EQUINOVARUS DEFORMITY IN ARTHROGRYPOSIS
AND SPINA BIFIDA
M. B. MENELAUS, MELBOURNE, AUSTRALIA
Fron the Orthopaedid Departnzeizt, Roi’aI C/iik/ren’s Hospital, A4elbour,ze
Excision of the talus was first performed for tuberculosis and for the effects of trauma
in adults. Whitman advocated its excision for paralytic calcaneus deformity and the operation
was later employed for a variety of paralytic deformities (Whitman, R., 1901 , 1908, 19 10, 1914;
Whitman, A., 1921, 1922, 1931 ; Thompson 1939). The results were variable and the operation
is now seldom indicated for the conditions for which it was first performed. Nevertheless,
talectomy has a useful place in the management of the rigid talipes equinovarus that is seen
in some cases of arthrogryposis multiplex congenita and spina bifida (Menelaus 1967, 1971).
Limitations of soft-tissue release operations-It is appropriate here to consider the causes of
failure ofsoft-tissue release operations when used in the management ofthe gross equinovarus
deformity sometimes encountered in the two conditions mentioned. There are two main
causes : 1 ) inadequate initial correction, and 2) relapse after removal of plaster.
Inadequate initial correction-Tightness of the skin and soft tissues on the medial side may
prevent the foot from being placed in full correction at the time of operation. If the deformity
is not of the most severe degree, this difficulty may be overcome by further manipulation and
reapplication of plaster two weeks after the operation, or by performing a V-Y-plasty as
described by Sharrard and Grosfield (1968). Nevertheless, feet that are severely deformed have
insufficient skin and soft tissue on the medial side for either ofthese methods to be applicable.
Relapse after removal ofplaster-Relapse occurs because at operation the ankle joint and the
joints on the medial aspect of the foot have opened widely like the lid of a suitcase. This
usually happens to some extent when a medial release is done, but in severely deformed feet
the medial gap between the tarsal bones is so wide that adaptive changes will not occur despite
prolonged immobilisation : there is nothing to prop the medial joints open. Calcaneo-cuboid
excision shortens the lateral border of the foot so that the medial joints are less widely opened
when the foot is held in the corrected position, but this procedure is also inadequate if there
is marked deformity.
The principles of tabectomy-The reason for the success of talectomy is that it provides
sufficient laxity for both the equinus and varus deformities to be corrected without tension.
Moreover, the false joint thus created between the mortise and the calcaneus is stable and
relatively congruous when the foot is plantigrade: the foot has no tendency to relapse
because there is no medial tension and the new joint is in a stable position. The operation
must, however, be carefully performed to produce this stable situation.
A valid criticism of the procedure is that it is unphysiobogical and disturbs the normal
anatomy; for this reason it should be undertaken only for well defined indications which will
be discussed below. The operation has not been done, nor is it recommended, for congenital
talipes equinovarus occurring as an isolated condition.
The follow-up in this series is short, but the early results are considerably better than
those previously obtained by supramalleolar osteotomy. The author has been unable to find
any report of a series with either a short or long follow-up of talectomy for rigid congenital
equinovarus deformity. The few long-term results that have been mentioned in the literature
have been uniformly good (see below).
468 THE JOURNAL OF BONE AND JOINT SURGERY
TALECTOMY FOR EQUINOVARUS DEFORMITY IN ARTHROGRYPOSIS AND SPINA BIFII)A 469
FIG. 4
Case 1-A child with arthrogryposis multiplex congenita at the age of 4 years and 8 months with
untreated equinovarus. The child also showed knee rigidity, dislocation of the left hip, elbow rigidity and finger
deformities characteristic of this condition. Figures 1 and 2 show the appearance of the feet before operation
and Figures 3 and 4 the appearance four years after bilateral talectomy. His activity was then nearly normal
and there were no shoe problems. He had also had an open reduction of the left hip, a left innominate
osteotomy and tendon transfers to restore active flexion of both elbows.
The operation of excision of the head and neck of the talus was described for the treatment
of calcaneus deformity (Janek 1949). This operation has also been used in the treatment of
severe rigid equinovarus deformity but the author has no experience of it.
Indications (Table 1)-The operation has been done in children suffering from arthrogryposis
multiplex congenita (twenty-five operations) and spina bifida (sixteen operations). Two feet
with late untreated congenital vertical talus in spina bifida were subjected to the procedure:
the remainder were equinovarus feet.
The indications for talectomy in arthrogryposis or in arthrogrypotic-like deformity in
spina bifida are: 1) badly deformed equinovarus feet; 2) very rigid feet; and 3) multiple
disabilities making prolonged standing unlikely. (Frequently caliper support is necessary for
reasons other than the foot deformity.) Generally less radical surgery will have been performed
before a foot requires excision of the talus. However, previous less radical surgery need not
necessarily precede talectomy : if a child presents late with severe deformity the operation may
be performed as a primary procedure (Figs. 1 to 4).
Age at operation-Operation has been done from the ages of five months to nine years and
eight months, the mean age at operation being three years. Triple fusion is to be preferred
if the child is old enough for that operation, and talectomy should be performed only if the
child cannot be tided over until the age for triple fusion. It seems that the procedure is most
likely to give good results when done between the ages of one year and five years.
VOL. 53 B, NO. 3, AUGUST 1971
470 M. B. MENELAUS
OPERATION
The operation is done in a bloodless field through a curved lateral incision which follows
the line of the subtalar and tabo-navicular joints. The ankle, subtalar and midtarsal joints are
opened at an early stage and the ligaments of these joints divided using eye scissors. These
scissors tend to keep to the plane of a joint without damaging articular cartilage. As the
dissection proceeds, the foot is manipulated into increasing equinus and varus so that the
posterior and medial ligaments can be divided under vision. The talus is held in a towel clip
TABLE I
INDICATIONS FOR TALECTOMY
Diagnosis Number of feet
Arthrogryposis multiplex congenita 25
Spina bifida
Equinovarus deformity . . 14
Vertical talus . . . . 2
Total . . . . 41
TABLE II
RESULTS OF TALECTOMY
Results Number of feet Percentage
Good . . . . 32 79
Residual equinus . . 6 14
Residual equinus and varus 3 7
Total . . . 41 100
and is displaced in each direction as the dissection proceeds. Generally the bone can be removed
in one piece : sometimes a fragment breaks off and requires removal with bone nibblers. The
tendo calcaneus is divided under vision and a portion of it is excised. Frequently the upper
surface of the calcaneus does not fit nicely into the mortise because the lateral malleolus
tends to abut against the lateral surface of the calcaneus. In these circumstances the tip of
the lateral malleolus may be excised and the inferior tibio-fibular ligaments divided. The
calcaneus should be thrust posteriorly in the mortise to give a normal contour to the back of
the heel. It might be argued that by thrusting the calcaneus posteriorly we are increasing the
mechanical advantage ofthe calfmuscle, which might lead to a recurrence ofequinus deformity.
In fact recurrence of significant equinus is not common, whether or not the tendo calcaneus is
divided at the time of talectomy.
The lower half of the outer surface of the lateral malleolus should be trimmed because
it may otherwise be difficult to accommodate the breadth of the usually low lateral malleolus
in a normal shoe.
Two variations of technique have been made when demanded by special circumstances.
1) If the calcaneus is not stable in the mortise a Kirschner wire is passed upwards through
the heel. The wire is removed after four weeks. 2) It is sometimes uncertain whether a deformity
could be corrected by a soft-tissue release or whether talectomy will be necessary. In these
circumstances a medial release operation is performed, and if when the foot is placed in a
THE JOURNAL OF BONE AND JOINT SURGERY
TALECTOMY FOR EQUINOVARUS DEFORMITY IN ARTHROGRYPOSIS AND SPINA BIFIDA 471
position of calcaneo-valgus the joints on the inner side of the foot open up to such an extent
that the talus almost falls out, then it is best to proceed with excision of the talus, which can
be completed through the medial approach.
Management after operation-The foot is immobilised in plaster for six weeks with the heel
in slight valgus and the ankle in neutral position.
A
FIG. 6 FIG. 7
Case 2-The feet of a child with a myelomeningocele and severe bilateral rigid equinovarus deformity which
had relapsed after bilateral tenotomy of the tendo calcaneus, serial plasters and bilateral radical postero-medial
release procedures. Figure 5 shows the feet before operation and Figures 6 and 7 three years and eight months
after bilateral talectomies which were done at the age of two and a half.
RESULTS
Forty-one operations were performed on twenty-three children, there being five unilateral
and eighteen bilateral procedures (Table II). The longest follow-up is four years, with an
average of two and a half years. Operations done in the past eighteen months have been
excluded.
Thirty-two feet (79 per cent) had a good result in that the foot was plantigrade and of
near normal appearance (Figs. 5 to 1 1). The rigidity of the new joint was no greater than that
of the ankle before operation.
Six feet (14 per cent) had some residual equinus but no varus. The feet fitted well into
shoes and it seems unlikely that further surgery will be necessary. Indeed Tompkins, Miller
and O’Donoghue (1956) emphasised the desirability ofmoderate fixed equinus after talectomy,
in order to improve “push off” in walking.
Three feet (7 per cent) have residual equinus and varus. These three feet will need a
further operation. This brings up the question as to what form any further surgery should
VOL. 53B, NO. 3, AUGUST 1971
472 \I. B. MENILAUS
FIG. 8 FIG. 9
Case 3-A girl aged 3 years with a myelomeningocele and bilateral talipes equinovarus for which she had had
bilateral tenotomy of the tendo calcaneus, serial plasters and bilateral posterior and medial soft-tissue release
operations. Figures 8 and 9 show that the right foot had relapsed into an equinovarus deformity, which was
fixed. Figures 10 and I I show the feet two and a half years after right talectomy. The sole is satisfactorily
aligned for weight-bearing and there are no callosities despite prolonged weight-bearing every day.
take. When, in the past, talectomy was done for calcaneus deformity it was sometimes revised:
scar tissue was excised, the mortise widened, the navicular excised if necessary and the calcaneus
replaced. Another procedure which has been performed in older children is fusion of the tibia
to the calcaneus (Carmack and Hallock 1947). One or other of these procedures, combined
with division of any strands of tendo calcaneus that may have re-formed, will have to be done
on our three cases that failed.
Holmdahl (1956) reports a 34 per cent incidence of bony ankylosis following talectomy
(chiefly for paralytic deformity). Although bony fusion has not yet occurred in any of the
children recorded here it may do so later: this would not significantly detract from the
value of the procedure.
DISCUSSION
Talectomy has a useful place in the management ofgross and rigid equinovarus deformity
in arthrogryposis multiplex congenita and spina bifida. Those few feet in which deformity
persisted after talectomy had the deformity from soon after the time they came out of the first
plaster: there was little tendency to relapse later. It is, therefore, likely that the feet which
have been classified as “good” will remain so. Although the follow-up is short the short-term
results are much better than the short-term results of supramalleolar osteotomy which is
followed by early relapse into deformity. Few long-term results of talectomy. done for
equinovarus, are mentioned in the literature. One good result, twenty years after operation,
was described by Tompkins, Miller and O’Donoghue (1956). This was the only patient in
their series in which equinovarus deformity provided the indication for excision of the talus.
THE JOURNAL OF BONE AND JOINT SURGERY
TALECTOMY FOR EQUINOVARUS DEFORMITY IN ARTHROGRYPOSIS AND SPINA BIFIDA 473
Young (1962) reported a woman who had bilateral talectomy by Sir William Macewen
for talipes equinovarus and who attended the Glasgow Infirmary fifty years later with feet
that were most satisfactory.
Excision of the talus without the restoration of muscle balance gave bad results when it
was used in the treatment of paralytic equinovarus deformity; it also gave generally poor
results when done in adults for the late results of injuries. But talectomy has given good
results when used in the first ten years of life in the treatment of severe talipes equinovarus
in arthrogryposis multiplex congenita and spina bifida. It may well be that by excising the
talus, the tendency to rigidity, which usually works against success in arthrogryposis, is turned
from an enemy to a friend.
SUMMARY
1. The indications for talectomy in the treatment of equinovarus deformity in arthrogryposis
multiplex congenita and spina bifida are discussed.
2. The technique of the operation is described, with variations which may be necessary in
special circumstances.
3. The results of forty-one operations are analysed.
4. It is concluded that the operation has a useful place in the management of equinovarus
deformity in arthrogryposis multiplex congenita and spina bifida, especially between the ages
of one and five years.
REFERENCES
CARMACK, J. C., and HALLOCK, H. (1947): Tibiotarsal Arthrodesis after Astragalectomy: A Report of Eight
Cases. Journal of Bone and Joint Surgery, 29, 476.
HOLMDAHL, H. C. (1956): Astragalectomy as a Stabilising Operation for Foot Paralysis following Poliomyelitis:
Results of a Follow-up Investigation of 1 53 Cases. Acta Orthopaedica Scandinavica, 25, 207.
JANEK, J. (1949): Partial Astragalectomy in Pes Calcaneus. Sborizik pro Chfrurgii Pohybov#{233}ho (Jstroji, 16, 138.
MENELAUS, M. B. (1967): Orthopaedic Management in Meningomyelocele. In Proceedings of the Fifth
International Congress of the World Federatio,z of Physical Therapy, Melbourize, Australian Physiotherapy
Association, p. 41.
MENELAUS, M. B. (1971): The Orthopaedic Management of Spina B(fida (‘ystica. Edinburgh and London:
E. & S. Livingstone.
SFIARRARD, W. J. W., and GROSFIELD, I. (1968): The Management of Deformity and Paralysis of the Foot in
Myelomeningocele. Journal of Bone and Joint Surgery, 50-B, 456.
THOMPSON, T. C. (1939): Astragalectomy and the Treatment of Calcaneovalgus. Journal of Bone and Joint
Surgery, 21, 627.
TOMPKINS, S. F., MILLER, R. J., and O’DONOGHUF, D. H. (1956): An Evaluation ofAstragalectomy. Southern
Medical Journal, 49, 1128.
WHITMAN, A. (1921): The Whitman Operation as Applied to Various Types of Paralytic Deformities of the
Foot. Results in the Average Case. Medical Record, 99, 302.
WHITMAN, A. (1922): Astragalectomy and Backward Displacement ofthe Foot. An Investigation ofits Practical
Results. Journal of Bone and Joint Surgery, 4, 266.
WHITMAN, A. (1931): Astragalectomy. Ultimate Result. American Journal ofSurgery, II, 357.
WHITMAN, R. (1901): The Operative Treatment of Paralytic Talipes of the Calcaneus Type. Transactions of the
Americaiz Orthopedic Associatioiz, 14, 178.
WHITMAN, R. (1901): The Operative Treatment of Paralytic Talipes of the Calcaneus Type. America,,
Journal of the Medical Sciences, 122, 593.
WHITMAN, R. (1908): Further Observations on the Treatment of Paralytic Talipes Calcaneus, by Astragalectomy
and Backward Displacement of the Foot. A,i,zals ofSurgery, 47, 264.
WHITMAN, R. (1910): Further Observations on the Operative Treatment of Paralytic Talipes of the Calcaneus
Type. American Journal of Orthopedic Surgery, 8, 1 37.
WHITMAN, R. (1914): Further Observations on the Operative Treatment of Paralytic Talipes, Calcaneus and
Allied Distortions. Medical Record, 85, 47.
YOUNG, A. B. (1962): Club Foot Treated by Astragalectomy; SO-year Follow-up of a Case. Lancet, i, 670.
VOL. 53B, NO. 3, AUGUST 1971
