British Journal of Neurosurgery (1995) 9, 659± 666

ORIGINAL ARTICLE

Adult postrepair myelomeningocoele and tethered cord

syndrome: good surgical outcome after abrupt neurological

decline

A. G. FILLER 1,3, J. A. BRITTON 2, D. UTTLEY1 & H. T. MARSH 1

Departments of 1Neurosurgery and 2Neuroradiology, Atkinson Morley’ s Hospital, London, UK and3Department of Neurological Surgery, University of Washington, Seattle, USA

Abstract

Adults who have had repair of an open myelomeningocoele at birth are susceptible to a variant of adult onset

tethered cord syndrome (ATCS). Precipitous and profound loss of lower extremity motor function occurred in

two postrepair adult patients, but was not seen in any of our 12 cases of adult tethered cord with any other

aetiologies. Both postrepair ATCS patients made a good recovery after surgical release of the tether. For the

patients with other aetiologies, surgery yielded improvement or recovery of urinary continence in 57%, relief from

pain in 78% and improved strength in 80%. Evidence of retethering was observed in 25% of the operated patients

at intervals ranging from 1 to 9 years postoperatively. We conclude that surgical release of tether can reverse

incontinence in ATCS of any aetiology and that in the post-myelomeningocoele repair patient, both dexam-

ethasone and surgical intervention are helpful in reversing acute neurological deterioration.

Key words: Acute paraplegia, incontinence, lipomyelomeningocoele, myelomeningocoele, spina bi® da, steroids, tethered

cord syndrome.

Introduction

The mortality of open myelomeningocoele

was nearly 90% in 1950,1 but a series of tech-

nical advances has gradually reversed the odds

so that more than 85% of such children are

now expected to survive into adulthood.2

Since the incidence of open dysraphism con-

tinues at 1± 4/1000 live births,3 the late compli-

cations of myelomeningocoele repair can

therefore be expected to become an increasing

problem in the adult patient population.

Consideration of two such patients who pre-

sented with severe and precipitous lower ex-

tremity neurological deterioration has

prompted this report. The general setting for

both cases is similar to adult onset tethered

cord syndrome in patients with spina bi® da

occulta, but may need to be considered and

managed somewhat differently because of the

rather different clinical course we have ob-

served.

In addition, we report 13 cases of adult

presentation tethered cord syndrome with

varying aetiologies other than post-repair

myelomeningocoele in patients ranging from

19 to 83 years of age. The results of their

management are then compared with the

postrepair myelomeningocoele patients and to

the results of treatment of adult tethered cord

syndrome reported from other institutions.

0268-869 7/95/050659 ± 05 Ó 1995, The Neurosurgical Foundation

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

660 A. G. Filler et al.

Clinical materials and methods

The case notes of all adult patients admitted

to Atkinson Morley’ s Hospital (AMH) be-

tween 1967 and 1991, and diagnosed as hav-

ing spinal dysraphism or tethered cord

syndrome were reviewed. These admissions

re¯ ect referrals from the South West Thames

region for which AMH provides neurosurgical

cover, a catchment area of approximately

three million people.

All such patients who had radiological stud-

ies (myelography or MRI) con® rming a low

lying conus medularis and who had symptoms

referable to a tethered cord were included.

Those patients who had onset of their present-

ing symptom prior to age 18 years were ex-

cluded. To con ® rm the status of postrepair

myelomeningocoele in the two patients with

that diagnosis, case notes clearly describing

surgical closure of an open defect within sev-

eral days of birth were located.

The age of the patients ranged from 19 to

83 years with a mean of 34, including six

males and eight females. Twelve of the 14

patients had surgery to relieve tethering. One

patient had three operations, each one of

which treated an apparent retethering. Follow

up varied from 1 to 20 years with a mean of

4.5 years.

Description of cases and results

Post-repair myelomeningocoele

Case 1. This was a 19-year-old male who had

closure of an open draining myelomeningo-

coele at birth (at Atkinson Morley’ s Hospital),

but who did not require a ventricular shunt.

He was able to walk during his ® rst year and

ultimately was able to play football and cricket

at school. With no prodromal symptoms, he

suffered a sudden and profound loss of

strength in his right leg while playing golf

which was associated with bilateral lower ex-

tremity paraesthesiae.

These symptoms resolved substantially over

several days, but subsequently recurred in a

series of episodes each of which left him with

a progressively severe ® xed de® cit and increas-

ing spasticity. Nine months after the ® rst epi-

sode, he developed a ® xed bilateral foot drop

and was then referred by his neurologist for a

neurosurgical evaluation. At that time, he had

0± 1/5 strength in both ankles and 3/5 strength

at his hips. He had marked bilateral hy-

perre¯ exia and was unable to walk indepen-

dently.

Myelography demonstrated a bow-stringed

tethered spinal cord with marked L2/L3

spondylolisthesis and stenosis. He had

laminectomy with release of the tether. There

was an immediate improvement of strength

although the spasticity resolved only gradually

over an 18-month period. By 2 years after the

operation, he as able to walk and drive, al-

though he still had some mild residual spastic-

ity and ankle weakness.

Case 2. This 22-year-old woman, had closure

of an open myelomeningocoele and placement

of a ventricular shunt as a neonate. She was

able to walk at 1 year of age, but remained

incontinent and so had an ileal conduit placed

at age 5 years. She tolerated a pregnancy well

(Caesarean delivery), but began experiencing

back pain about 1 year postpartum. The pain

recurred episodically for several months and

she commenced intermittently wearing a

polystyrene jacket which an orthopaedic sur-

geon had prescribed 4 weeks prior to this

admission.

On the day prior to her admission, she had

progressively severe burning pains in her legs.

On the day of admission, while sitting, she

suffered the abrupt loss of all voluntary move-

ment in both legs. Upon urgent transfer to our

neurosurgical centre, she had 1± 2/5 strength

in all muscle groups of both legs with dimin-

ished knee jerks but absent ankle jerks. She

also had some progression of her usual patchy

lower extremity sensory de® cit.

Dexamethasone, 10 mg IV initially and then

4 mg IV 6-hourly, was commenced immedi-

ately and, because she regained some move-

ment (2± 3/5) in some muscle groups, steroids

were continued for several days. Plain radio-

graphs demonstrated spondylolisthesis (Fig. 1)

and CT-m yelography demonstrated a tautly

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

Adult postrepair myelomeningocoele 661

FIG. 1. Lateral radiograph demonstrating spondylolis-

thesis at L5/S1 in a postrepair myelomeningocoele

patient with acute neurological deterioration from adult

onset tethered cord syndrome.

years postoperatively. MRI performed at the

time of the transient recurrence demonstrated

the neural placode to be untethered although

possibly adherent to the posterior wall of the

thecal sac (Fig. 4).

FIG. 2. (A) Axial myelogram CT scan at the time of

acute onset of paraplegia in post-repair myelomeningo-

coele patient. The cord is attached posteriorly in the

thecal sac and the tautly stretched nerve roots can be seen

as thin black lines extending towards the foramina. (B)

1Ð articulation; 2Ð thecal sac; 3Ð portion of bi® d spinal

lamina; 4Ð nerve root under tension; 5Ð portion of

neural placode under tension; 6Ð area of adhesion

between neural placode and dura.

tethered spinal cord with stretched nerve roots

under apparent tension (Fig. 2) and with the

cord apparently drawn under bow string

tension against the laminae (Fig. 3). She did

not complain of headache, and did not have

hydrocephalus, nor hydromyelia (by delayed

postmyelogram CT).

Her improvement on steroids plateaued, so

a laminectomy and untethering of the spinal

cord were carried out. During the following

3± 5 days she had complete recovery of lower

extremity strength and was able to walk out of

the hospital unassisted upon discharge to

home. She had an episode of bilateral lower

extremity weakness nine months later, but this

resolved with steroids alone and she has since

continued with no additional symptoms to two

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

662 A. G. Filler et al.

FIG. 3. (A) Sagittal reconstruction of myelogram CT of

postrepair myelomeningocoele patient, demonstrating

`bow stringing’ of the spinal cord which pulls it into

contact with the laminae. (B) 1Ð thecal sac; 2Ð spinal

cord; 3Ð spinal lamina in contact with spinal cord.

Surgical outcome for the entire group was

generally quite good. Strength improved by at

least one grade in 80% of those presenting

with weakness although one patient was

weaker postoperatively. The two postrepair

myelomeningocoele patients improved in

strength by more than two grades. There was

substantial improvement or relief of pain in

78% of the patients with this symptom. In

57% (4/7) of the patients presenting with new

onset incontinence, surgery succeeded in sub-

stantially improving or completely restoring

sphincter control.

Maintenance of gains over the period of

follow-up was generally good, but two patients

reported recurrence of progressive weakness

beginning 4 years (in a patient with diastem-

atomyelia) and 6 years (in a case of thoracic

FIG. 4. Sagittal plane MRI of postrepair myelomeningo-

coele patient 1 year after operation for release of tether.

The neural placode can be seen untethered, near the

posterior wall of the thecal sac.

Summary of all cases

Of the 14 con® rmed cases of adult onset teth-

ered cord syndrome, the aetiology was

lipomyelomeningocoele in four (29%),

diastematomyelia in three (21%), thickened

® lum terminale in three (21%), postrepair

myelomeningocoele in two (14%), thoracic

meningocoele in one (7%) and multiple spinal

abnormalities in one (7%) (see Table I). The

presenting symptoms were weakness (71%),

incontinence (57%) and pain (50%). Duration

of symptoms ranged from 5 h to 10 years,

although nearly all had some accelerated pro-

gression of their symptoms over several weeks

prompting their referral to the neurosurgical

centre.

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

Adult postrepair myelomeningocoele 663

TABLE I. Summary of ATCS cases

Age (years)/Sex Diagnosis Operation Outcome Presentation

19/M Myelomeningocoele Lami strengthÝ R leg weakness: 9 months

Bilat foot drop: 1 week

22/F Myelomeningocoele Lami/Unteth strengthÝ, sensÝ pain: 10 months

painß paraplegia: acute

40/F Lipomyelomeningocoele Lami/Unteth strengthÝ, painß leg weakness: 6 months, pain

GUÝÝ urgency: 3 months

29/M Lipomyelomeningocoele Lami/Unteth sensationÝ, GUÝÝ incont: 1 month

27/F Lipomyelomeningocoele Lami/Unteth pain: no D arm and leg pain: 10 years

R leg paraesthesias: 4 months

22/M Lipomyelomeningocoele no surgery L leg weakness: 1 year

83/F Lipomyelomeningocoele no surgery urinary incont: 5 weeks

leg weakness: 2 weeks

29/F Thick Filum Terminale Lami/Unteth GU: no D incont: 8 weeks

30/M Lipomyelomening/Conus Lami/Drain strengthß , painß prog. weakness: 2 year

and Cauda Equina Abscess GUß43/F Diastematomyelia Lami/Unteth painß , GUÝ double incont: weeks

pain: 10 years

19/F Diastematomyelia Lami/Unteth strengthÝ, painß pain and leg weakness

21 Recurrent tether Lami/Unteth strengthÝ, rapid prog. leg weakness

29 Recurrent tether Lami/Unteth strengthÝ, pain;ß pain and leg weakness

32/M Diastematomyelia Lami/Unteth strength: no D , prog. incont: 1 year

GU: no D weakness: 10 year

40/M T4 Meningocoele Lami/Unteth strengthÝ prog. weakness: 3 years

GUÝ prog. incont: 1 year

47F Mult. Abn./stenosis C & L Lami strengthÝ, painß , pain, urinary urgency,

GU: no D leg weakness: 5 weeks

Ýincreased; ßdecreased; ÝÝmarkedly increased; no D no change.

meningocoele) postoperatively. Another of the

diastematomyelia patients suffered an acute

deterioration 16 months postoperatively, im-

proved with a second surgery, had recurrent

weakness from retethering 9 years later, im-

proved again with surgery, but then once more

developed weakness another 9 years later. The

female postrepair myelomeningocoele patient

had a transient recurrence of weakness 1 year

postoperatively, but regained full strength

without surgical intervention.

There were no deaths; one patient had a

super® cial wound infection and one developed

a draining cyst requiring surgical exploration.

There were two with CSF leaks, one of whom

required reoperation for repair. Drainage of an

intradural abscess of the conus and cauda

equina in one patient relieved pain, but re-

sulted in severe weakness and new onset in-

continence postoperatively.

Discussion

Aetiology of adult tethered cord syndrome

Cases of adult onset of tethered cord syn-

drome have been reported sporadically from

the mid-nineteenth century,4,5 but were gener-

ally considered to be consequent upon growth

of intradural fatty tumours.6,7 The syndrome

seems to have been de® ned initially by reports

from Lassman and James,8 and by Loeser and

Lewin,9 although the series of 12 patients re-

ported by Kaplan and Quencer,10 two patients

from Gokay et al.,11 23 patients from Pang and

Wilberger12 and eight patients from Lesoin et

al.13 have extensively de® ned the range and

character of the syndrome. In a recent review,

Yamamura et al.14 summarize reports in the

literature in a total of 57 patients.

Very few of these patients, however, are

clearly postrepair myelomeningocoele patients

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

664 A. G. Filler et al.

In some cases, there is uncertainty because

of imprecise use of the term `myelomenin-

gocoele’ as in a report from Logan et al.15 of

an active duty Marine described as a post-

operative myelomeningocoele patient, but also

described as having `occult spina bi® da’ .

There is also a report of a 72-year-old

woman16 who was a postrepair myelomeningo-

coele patient by her own report, and who

suffered a fairly rapid onset of leg weakness

and double incontinence (the complete time

course is not fully described). Moufarrij et al.17

report two such cases, but with limited infor-

mation given on the time course or severity of

symptoms. One of the 23 cases reported by

Pang & Wilberger12 is a postrepair patient.

Thus, including the 57 patients listed by Ya-

mamura et al.,14 and additional cases from

Moufarrij et al.,17 Logan et al.,15 and Wilden

and Hadley,16 and this report, only seven of

the eighty reported cases of adult onset teth-

ered cord syndrome or 8.8% are postrepair

myelomeningocoele patients.

This situation contrasts sharply with the mix

of aetiologies among paediatric patients where

Heinz et al.18 report that as many as two-thirds

of all tethered cord explorations were for

postrepair myelomeningocoele. A comparable

® gure from Moufarrij et al.17 is that postrepair

myelomeningocoeles make up 40% of the total

number of paediatric tethered cord patients

who come to surgery, the remainder being

attributed to various forms of spina bi® da

occulta. The difference in percentage between

these two reports may re¯ ect local differences

in practice or it may re¯ ect the increasing role

of prophylactic release of tether in spina bi® da

occulta which would dilute the impact of the

spina bi® da aperta cases upon the operative

patient population.

Incidence of postrepair tethering

In Pang & Wilberger’ s series of adult cases

from 1982,12 postrepair myelomeningocoele

cases make up 4.3% of the total, while in our

series they make up 14%. It should be noted

that if the Atkinson Morley’ s Hospital results

had been reviewed in 1982, at the same time

as the data from the University of Pittsburgh,12

we would have had eight cases of adult teth-

ered cord syndrome none of which were

postrepair myelomeningocoeles.

All postrepair myelomeningocoele patients

have low lying spinal cords upon MRI.19

Thus, it can be expected that radiological evi-

dence of tether will always be found when an

adult postrepair patient presents with new

neurological symptoms whether or not the

tether is the cause of the symptoms. In the

paediatric population, the frequency of symp-

tomatic tethering among post-repair patients is

variously reported from 3% 1 to 15%.19 Hy-

dromyelia is an alternative cause of late de-

terioration in adult patients20 and must be

carefully excluded before attributing the de-

terioration to cord tethering. There are in-

suf® cient data at this point to predict whether

symptomatic tethering will occur in adult

post-repair patients at the same frequency as it

occurs in the paediatric population.

Pathophysiology

The mechanism by which the decline develops

in adult onset tethered cord appears to be

degenerative. This is in distinction to the pae-

diatric situation where a tethered cord is

gradually stretched by normal growth. In

adults, it appears that a tethered cord decom-

pensates neurologically when a routine adult

degenerative process causes impingement

upon the abnormally positioned cord. Both of

our postrepair patients had spondylolisthesis

which appeared to have caused the decompen-

sation of the already stretched spinal cord.

It has been suggested that relative to the

paediatric situation, the adult tethered cord

syndrome is typi® ed by a more gradual and

insidious onset of symptoms, and that pain is

a characteristic feature.12 In our two postrepair

myelomeningocoele patients, however, the

presentation was sudden, severe, and painless.

In both cases it was the motor rather than the

sensory change that was more striking.

As can be seen in Fig. 3, the mechanical

impact upon the spinal cord is by laminae

impinging upon its posterior aspect and this

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

Adult postrepair myelomeningocoele 665

might be expected to cause sensory symptoms

to predominate. However, if the symptoms

were based on compromise of tissue in the

repaired neural placode itself, then the ventral

gray matter would be closer to the posterior

aspect of the cord. Alternatively, it may be the

extreme lordosis which causes stretching of

the anterior aspect of the cord, involving either

the ventral gray matter or the corticospinal

tracts.

Steroids and tethered cord syndrome

There has been little use of steroid medication

in the treatment of tethered cord syndrome as

it occurs in adults or in children. The presen-

tation of most tethered cord syndrome pa-

tients is with gradual progression over months

and years. Once the diagnosis is made, surgi-

cal treatment can usually be carried out before

signi® cant further deterioration can occur.

However, the sudden onset of symptoms in

our second post-myelomeningocoele repair

patient led us to a trial of steroids and, at least

in that case, they yielded a clear response.

Response to surgery

The surgical outcomes for our entire group of

14 patients is generally similar to the results

reported by Pang and Wilberger12 (see Table

I). Long-term follow-up reveals that while

most patients maintain their gains well, there

is nonetheless a de® nite risk of retethering

after successful operation in adults. Although

these patients have no further growth in height

after the release, they do continue to be sub-

ject to progressive degenerative spinal disease

which may cause the neurological symptoms

to recur. Retethering was con ® rmed in two

patients both of whom had diastematomyelia

and probably occurred in a third whose tether

was due to a thoracic meningocoele.

It is possible that such a development did

occur in the postrepair myelomeningocoele

patient who had transient recurrence after 1

year, but her improvement on steroids alone

suggests the episode was due to direct trauma

on the exposed neural placode associated with

her untreated spondylolisthesis. Two years af-

ter her surgery she retained excellent lower

extremity strength.

Surgery failed to relieve pain in one patient

who had been experiencing pain for 10 years

prior to the development of the numbness

which brought her to surgery. There was a

poor outcome in a patient whose presentation

was precipitated by the development of an

abscess in the area of the lipoma. In all the

more routine cases where mechanical factors

alone had caused symptoms of one year or less

in duration we achieved satisfactory results.

There was no regular pattern for predicting

which patients would regain urinary conti-

nence, but our 57% success rate with this

symptom does suggest that it is at least a

reasonable expectation that release of tether

can improve incontinence. Thus, new onset

incontinence in an adult with tether is not a

hopeless fait accompli but rather should be

considered an indication for prompt surgical

release of the tether.

Acknowledgements

The Neurosciences Research Foundation of

Atkinson Morley’ s Hospital and the Wellcome

Trust are thanked for their support to AGF.

Address for correspondence: A. G. Filler, Depart-

ment of Neurosurgery, Atkinson Morley’ s

Hospital, 31 Copse Hill, Wimbledon SW20

0NE, UK.

References

1 McClone DG, Naidich TP. Myelomeningocele:outcome and late complications. In: McLaurin RL,Schut L, Venes JL et al. eds. Pediatric Neuro-surgery, 2nd edn. Philadelphia: WB Saunders,1989; 53± 70.

2 Guthkelch AN. Aspects of the surgical manage-ment of myelomeningocele: a review. Dev MedChild Neurol 1986; 28:525 ± 32.

3 Reigel DH. Spina bi® da. In: McLaurin RL, SchutL, Venes JL et al. eds. Pediatric Neurosurgery, 2ndedn. Philadelphia: WB Saunders, 1989 ; 35± 52.

4 Beykirch A. Klinischer Beitrag zur Beurteilung dermyelographischen RoÈ ntgenbilder. Zugleich Mit-teilung uÈ ber einen Fall eines reinen seltenen in-

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

666 A. G. Filler et al.

traduralen, extrameullaÈ ren Lipoms. Beitr klin Chir

1928; 142:301 ± 21.

5 Turner, FC. Lipomatous tumour (?sarcoma) of the

spinal cord. Trans Path Soc London 1888; 39:25 ±7.

6 DiBiagio F. Malformazioni rachidee multiple con

lipoma della cauda. Riv Neurol 1959 ; 29:401 ± 9.7 Dubowitz V, Lorber J, Zachary RB. Lipoma of the

cauda equina. Arch Dis Childh 1965; 40:207 ± 13.

8 Lassman LP, James CCM. Lumbosacral lipomas:

critical survey of 26 cases submitted to laminec-tomy. J Neurol Neurosurg Psychiatry 1967;

30:174± 81.

9 Loeser JD, Lewin RJ. Lumbosacral lipoma in the

adult. J Neurosurg 1968; 29:405 ± 9.10 Kaplan JO, Quencer RM . The occult tethered

conus syndrome in the adult. Radiology 1980;

137:387 ± 91.

11 Gokay H, Barlas O, Hepgul KT, Hicdonmez T.Tethered cord in the adult mimicking the lumbar

disc syndrome: report of two cases. Surg Neurol

1993; 39:440 ± 2.12 Pang D, Wilberger JE. Tethered cord syndrome in

adults. J Neurosurg 1982; 57:32 ± 47.

13 Lesoin F, Petit H, Destee A et al. Spinal dysraphia

and elongated spinal cord in adults. Surg Neurol1984; 21:119 ± 24.

14 Yamamura A, Niwa J, Hashi K et al. Tethered cordsyndrome of adult onset: report of a case and areview of the literature. No Shinkei Geka 1989;17:69± 73.

15 Logan SR, Fisher WS, Curcio CM. Tethered cordsyndrome in the adult postoperative myelo-meningocele patient. Spine 1989; 14:895 ± 7.

16 Wilden JN, Hadley D. Delayed tethered cord syn-drome after myelomeningocele repair. J Neurosurg1989; 70:815 ± 16.

17 Moufarrij NA, Palmer JM, Hahn JF et al. Corre-lation between magnetic resonance imaging andsurgical ® ndings in the tethered spinal cord. Neuro-surgery 1989; 25:341 ± 6.

18 Heinz ER, Rosenbaum AE, Scarff TB et al. Teth-ered spinal cord following myelomeningocele re-pair. Radiology 1979 ; 131:153 ± 60.

19 Tamaki, N, Shirataki K, Kojima N et al. Tetheredcord syndrome of delayed onset following repair ofmyelomeningocele. J Neurosurg 1988; 69:393 ± 8.

20 Park TS, Cail WS, Maggio WM et al. Progressivespasticity and scoliosis in children with myelo-meningocele: Radiological investigation and surgi-cal treatment. J Neurosurg 1985; 62:367 ± 75.

21 Adamson AS, Gelister J, Hayward R, Snell ME.Tethered cord syndrome: an unusual cause of adultbladder dysfunction. Br J Urol 1993; 71:417 ± 21.

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

British Journal of Neurosurgery (1995) 9, 667± 670

TECHNICAL NOTE

Long vascular pedicle cranial ¯ ap

ATUL GOEL

Department of Neurosurgery, K.E.M. Hospital, Parel, Bombay, India

Abstract

Two case reports illustrate a long vascular pedicle cranial bone ¯ ap. A split or full thickness skull bone ¯ ap is

based on the pericranium layer. The temporalis muscle with its overlying fascial layers and vascular pedicles form

the base of this ¯ ap and assure its adequate vascularization. The technique and its uses in the reconstruction of

calvarial defects is discussed.

Key words: Calvarium, reconstruction, temporalis muscle, vascularized ¯ ap.

Introduction

Temporalis muscle and pericranium have

been used to nourish cranial bone ¯ aps.1 ± 5 The

¯ ap described in this report is a split or full

thickness cranial bone ¯ ap based on the peri-

cranial layer which receives its vascular

nourishment from the temporalis muscle and

its overlying fascial layers. Such ¯ aps have

been described in plastic surgery literature and

have been used in malar reconstruction in

Treacher Collins syndrome.6 The dependable

vascularity, long length, local availability and

manoeuvrability of the ¯ ap render it versatile

with great potential for reconstruction of skull

convexity and basal defects. The described

¯ ap can be used particularly to reconstruct

cranial defects where there is poor local

nourishment and potentially infective areas

which are cosmetically crucial as in the de-

scribed reports.

Technique

Subgaleal elevation of the scalp is carried out.

The temporalis muscle with its overlying fas-

cial layers and the pericranial layer is retained

with the skull. The outer table of the skull

bone is split as shown in the Fig. 1 preserving

FIG. 1. Drawing showing the splitting of the calvarial

bone. The bone ¯ ap as shown by arrows is being elevated

along the pericranium. The temporalis muscle and its

fascial envelope form the pedicle of the ¯ ap.

0268-869 7/95/050667 ± 04 Ó 1995, The Neurosurgical Foundation

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

668 A. Goel

FIG. 2. Drawing shows an asterisk placed in the centre

of the frontal skull defect. The described ¯ ap will be cut

along the bold lines and rotated in the direction of the

arrows.

FIG. 3. The ¯ ap has been rotated over the frontal bone

defect. The temporalis muscle has been split vertically.

the overlying pericranial layer. A part of the

temporalis muscle (and fascial layers) along

with the pericranium is elevated and rotated as

required (Figs 2 and 3).

Case report 1

A 32-year-old man was admitted with a com-

plaint of frontal headache and a swelling on

the right side of the forehead for 5 years. He

also complained of diplopia and decreased vi-

sion in the right eye for 3 years. He had a well

circumscribed 6 3 6 cm. bony swelling over

the right supra-orbital region. Computer to-

mography (CT) and magnetic resonance

imaging (MRI) showed a right frontal extra-

cerebral enhancing lesion extending into the

ethmoid sinus. The thickening of the bone was

noted. A transnasal biopsy by the otolaryngol-

ogy unit con ® rmed that the lesion was a

meningioma. Four weeks after the ® rst pro-

cedure, the lesion was excised by the transcra-

nial route. The pericranium was thickened

and the region of the swelling was soft and

friable bone. There were large vascular chan-

nels from the scalp converging over the pro-

tuberance. The bony swelling and the

thickened pericranium were excised till normal

areas were seen. The dura underneath the

swelling was tumour ridden and was excised

with the intradural tumour. Tumour extension

into the ethmoid sinus was removed en-masse.

The dural defect was covered by a pericranial

graft. The bone defect was covered by a split

thickness posterior frontal ¯ ap with a vascular-

ized pedicle based on the pericranium and

temporalis muscle. The ethmoid sinus was

packed with fat taken from the abdominal

wall. The wounds healed well. When the pa-

tient was seen 4 months after the surgery the

¯ ap was well accepted (Fig. 4).

Case report 2

A 12-year-old boy underwent nephrectomy for

a Wilm’ s tumour. He developed a swelling on

the forehead considered to be a solitary met-

astasis from the kidney tumour. The swelling

was treated by local irradiation, but local pain

forced neurosurgical treatment. CT showed

the bony lesion in the frontal midline over the

forehead. Radiographs showed a sun-ray ap-

pearance of the lesion. The tumour was re-

sected piece meal with the help of chisel and

hammer and microdrill. After the entire tu-

mour had been resected a large bone defect

had been created. There was poor vascularity

of the area secondary to local irradiation and it

was considered that a free ¯ ap would not be

suitable for the large defect. A vascularized

pedicle temporalis musculofacial full thickness

bone ¯ ap was turned from the posterior fron-

toparietal region and placed over the bone

defect and sutured in place. Splitting of the

¯ ap was not possible due to the thin skull bone

in this child. Histological examination showed

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

Calvarial ¯ ap 669

FIG. 4. Radiograph with white arrow showing the donor

site where the cranial bone was split and black arrows

showing the receptor (case 1).

as described, and results in a viable ¯ ap with

an abundance of vascular supply.

Various studies have shown that vascular-

ized membranous bone transfers retain their

osseous mass to a greater degree than non-vas-

cularized bone grafts.1,3,12 The skull bone is

thickened superior to the temporal line which

marks the attachment of the temporalis mus-

cle. Splitting of the skull bone is easier in the

paramedian frontoparietal area bone owing to

the well formed diploic channels. The split

thickness graft can be broken into pieces and

can be suitably contoured preserving the at-

tachment of the pericranium. The dependable

blood supply, long length, ease of harvesting

and the ability to alter the arc of rotation of

this ¯ ap are advantageous. The other advan-

tages of such a ¯ ap include harvesting of grafts

of adequate size, ease of access within the

same operative ® eld, and no or minimal post-

operative morbidity and discomfort for the

patient. Such vascularized ¯ aps are more re-

sistant to infection, are mechanically stronger

and survive better in poorly vascularized bed

when compared with free bone grafts.

Acknowledgements

The author acknowledges with gratitude the

support and constant guidance of Dr Sunil K.

Pandya. Dr J. Nitta drew the illustrations. Dr

Naina Goel did the proof-reading.

Address for correspondence: A. Goel, Depart-

ment of Neurosurgery, K.E.M. Hospital,

Parel, Bombay 400 012, India.

References

1 Bite U, Jackson IT, Wahner HW, Marsh RW.Vascularized skull bone grafts in craniofacialsurgery. Ann Plast Surg 1987 ; 18:3 ± 15.

2 Casanova R, Cavalcante D, Grotting JC, VasconezLO, Psillakis JM. Anatomic basis for vascularizedouter-table calvarial bone ¯ aps. Plast Reconstr Surg1986; 78:300 ± 8.

3 Cutting CB, McCarthy JG, Berenstien A. Bloodsupply of the upper craniofacial skeleton: the searchfor composite calvarial bone ¯ aps. Plast ReconstrSurg 1984 ; 74:603 ± 10.

4 Price JC, Loury M, Carson, Johns ME. The peri

that the lesion was a benign ® brous dysplasia.

The forehead contour was acceptable when

the child was seen 6 months after the oper-

ation.

Discussion

An improved understanding of the vascular

supply of the temporalis muscle and its invest-

ing fascial layers has been exploited in various

reconstructive procedures.7 ± 10 The peri-

cranium comprises of an outer layer of loose

aereolar tissue and an inner layer of os-

teoblasts and contains extensive vascular net-

work.11 The pericranium can sustain the

calvarial ¯ ap by means of multiple small, verti-

cal perforators.2 The super® cial fascial layer

over the temporalis muscle is a part of the

pericranial aponeurosis whilst the deep tempo-

ral fascial layer completely invests the su-

per® cial aspect of the temporalis muscle. The

temporalis muscle and its fascial envelope re-

ceive their blood supply from the anterior,

middle and posterior deep temporal and su-

per® cial temporal arteries. Subperiosteal elev-

ation of the temporalis muscle along with the

fascial layers preserves the integrity of all the

major vascular supply. The split or full thick-

ness cranial bone is based on the pericranial

layer and the temporalis musculofascial layer

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.

670 A. Goel

cranial ¯ ap for reconstruction of anterior skull basedefects. Laryngoscope 1988; 98:1159 ± 64.

5 Watson Jones R. The repair of the skull defects bya new pedicle bone-graft operation. BMJ 1933;1:780.

6 G. McCarthy JG, Zide BM. The spectrum of cal-varial bone grafting: Introduction of the vascu-larised calvarial bone ¯ ap. Plast Reconstr Surg1884; 74:10 ± 17.

7 Goel A. Vascularised osteomyoplastic ¯ ap for cra-nial base reconstruction. Br J Neurosurg 1994;8:79± 82.

8 Habel G, Hensher R. The versatility of the tempo-ralis muscle ¯ ap in reconstructive surgery. Br J OralMaxillofac Surg 1986; 24:96 ± 101.

9 Abul Hassan HS, von Drasek Ascher G, AclandRD. Surgical anatomy and blood supply of thefascial layers of the temporal region. Plast ReconstrSurg 1986 ; 77:17 ± 28.

10 Matsuba HM, Hakki AR, Romm S, Little JW,Spear SL. Variations on the temporoparietal fascial¯ ap. Laryngoscope 1990; 100:1236 ± 40.

11 Habal MB, Maniscalco JE. Observations on theultrastructure of the pericranium. Ann Plast Surg1981; 6:103 ± 11.

12 Puckett CL, Hurvitz JS, Metzler MH, Silver D.Bone formation by revascularized periosteal andbone grafts, compared with traditional bone grafts.Plast Reconstr Surg 1979; 64:361.

Br

J N

euro

surg

199

5.9:

659-

670.

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Uni

vers

ity o

f B

ritis

h C

olum

bia

on 1

2/09

/14.

For

per

sona

l use

onl

y.