NEUROGENIC PROTRUDED
BLADDER
DYSFUNCTION
IN
LUMBAR DISK AND
AFTER LAMINECTOMY JENS T. ANDERSEN, WILLIAM
M.D.
E. BRADLEY,
M.D.
From the Department of Urology H, Gentofte Hospital, University of Copenhagen, Denmark, and Department of Neurology University of Minnesota, Minneapolis, Minnesota
ABSTRACT-Bladder and urethral innervation was studied in 18 patients with protruded lumbar disk or persistent back pain after laminectomy. A high incidence of neurogenic dysfunction of the detrusor muscle was found, whereas impaired function of the striated external urethral sphincter was rare. The lesions were encountered among the patients with protruded lumbar disk as well as among the patients with sequelae after laminectomy, suggesting that neurogenic bladder dysfunction in cauda equina injury due to protruded disk is often irreversible.
Neurogenic dysfunction of the urinary bladder due to nerve root compression from disk prolapse has been documented in the literature.lm5 However, these reports deal only with the cystometric findings in this disease. In the present study bladder and urethral innervation was studied in 18 patients with protruded lumbar disk or persistent back pain after laminectomy using cyssphincter electromyography,7 electometry, tromyelography,* and flowmetry.g We found a high incidence of disturbances in detrusor innervation, whereas neurogenic dysfunction of the striated external urethral sphincter was rare. The lesions were encountered in the patients with protruded lumbar disk as well as among those with sequelae after laminectomy for herniated disk. Methods Detrusor function was studied by means of gas cystometry.’ The patients were catheterized with an indwelling urethral catheter. The bladder was emptied and inflated with carbon dioxide at a constant rate of 200 cc. per minute. Intravesical pressure was recorded with a transducer and
94
amplifier calibrated in centimeters of water, and the pressure curves were displayed on one channel of a two-channel strip chart recorder. Sphincter function was studied recording anal sphincter activity utilizing electronic integration.’ By simultaneous recording of the electromyographic activity in the periurethral striated sphincter and the anal sphincter, we found that anal sphincter activity was similar to the concurrent activity in the striated urethral sphincter during bladder filling and detrusor reflex contraction. A bipolar concentric electromyographic recording electrode mounted on a Teflon, hourglass-shaped anal plug was inserted in the anal canal. Electromyographic activity was recorded simultaneously with the cystometrogram on the second channel of the strin chart recorder. The electromyographic potentials were integrated and recorded in arbitrary units. Voluntary control of the sphincter mechanism was tested asking the patients to contract and relax the anal sphincter. The spinal micturition reflex arc was studied by recording of spinal evoked potentials.* For assessment we used specially designed urethral
UROLOGY
/ JULY 1976
/ VOLUME
VIII,
NUMBER
1
TABLE
I.
Myelographic findings in 18 patients with lower back pain
No. of Patients
Level of Defect* Group I L3-4 L4-5 L&
-
3 2 3
Sphincter
8
TOTAL Group II
1
L-3 b,.,block
(arachnoiditis) h-s block L+~ block (arachnoiditis) Normal
1 1 1
-
6
10
TOTAL *Intervertebral
space.
catheters with two circular stimulation electrodes mounted in a position adjacent to the proximal urethra with the catheter inserted. Electrical stimulation of the posterior urethra or the intrinsic bladder wall evokes a contractile response in the anal sphincter. The evoked electromyographic responses were recorded from the anal sphincter and cyclically averaged. The latency or signal transit time of the reflex was measured on the graphs. Flowmetry was performed according to the method described by Von Garrelts.g Furthermore, myelography was performed in all 18 patients. Results Eighteen patients, 15 females and 3 males, were studied. The mean age was 39.7 years with a range of twenty-one to seventy-two years. Eight of the patients (Group I) had lower back pain due to protruded lumbar intervertebral disks and had not undergone previous back surgery, whereas the remaining 10 patients (Group II) had previous laminectomies because of herniated disks, and now presented persistent lower back pain. The myelographic findings in the 2 groups are listed in Table I. C ystometric
findings
All the patients with myelographic documented protruded lumbar disks without previous surgery had detrusor areflexia. We defined detrusor areflexia by a cystometrogram showing absence of detrusor reflex even when the bladder was distended to the point of sensory discomfort. In the group of patients with previous
UROLOGY
/ lULY1976 / VOLUMEVIII,
NUMBER
laminectomies, 7 patients had detrusor areflexia, whereas 3 patients had normal detrusor function. These 3 patients with normal cystometrograms had normal myelograms, but 3 of the patients with detrusor areflexia also presented normal myelograms.
1
electromyographic
results
Sixteen of the patients had a normal sphincter electromyogram indicating full voluntary control of the periurethral striated sphincter. One patient demonstrated a flaccid external sphincter with no recordable electromyographic activity during bladder filling and loss of the ability to contract or relax the sphincter on command. This patient had a myelogram demonstrating a protruded disk in the third to fourth lumbar interspace. Finally, 1 patient had detrusor sphincter dyssynergia. This syndrome was defined by a sphincter electromyogram showing increasing clonic sphincter contraction evoked by bladder distention, where the increased sphincter activity could not: be depressed voluntarily by the patient.’ Further, the patient was unable to contract the sphincter on command. This patient had a protruded disk at the fourth to fifth lumbar interspace. Spinal evoked responses were studied in 15 of the patients. The signal transit time in healthy volunteers has been reported in the range of 50 to 70 msec.8 In 1 patient no response could be elicited in the anal sphincter by electrical stimulation of the proximal urethra indicating a block of the reflex arc. This patient, furthermore, showed a flaccid sphincter on the sphincter electromyogram. The signal transit times in the remaining 14 patients had a mean value of 75.7 msec. with a range of 40 to 100 msec. However, 9 of these patients had latencies longer than 70 msec. indicating impairment of the segmental innervation of the bladder and urethra.
Flowmetry
results
Uroflowmetry was performed in 17 of the patients. Two patients were not able to void during the investigation. The maximum flow values in the remaining 15 patients had a mean of 23 cc. per second with a range of 3 to 50 cc. per second. Seven of the patients had maximum flow values lower than 15 cc. per second. The average flow values had a mean of 7.3 cc. per second (range: 1 to 22.4 cc. per second). Postvoiding residual volumes were obtained from 15 patients, and the residual volumes had a mean of 94.2 cc. ranging from 0 to 475 cc.
95
S ymptomatology The principal urinary bladder symptoms are shown in Figure 1. Straining and the subjective feeling of urinary retention were the symptoms most frequently encountered, and these symptoms were correlated to detrusor areflexia in the cystometric recordings. The 2 patients complaining of urinary frequency had normal cystometrograms and a normal sphincter electromyogram. Only 1 patient had urinary infection. URINARY BLADDER
NUMBER
OF PATIENTS
SYMPTOMS
STRAINING I RETENTION
.,.
OVERFLOW. INCONTINENCE
FREQUENCY
,.,I;,
1
0 8
, I
:.: ;
p I
I ; I
I
I
!zz[ I
I I
t I L 8 I
I 8 1
I
,
8 ,
I I
,
URGENCY
Urinary bladder symptoms in 18 patients with protruded lumbar disk or sequelae after laminectomy. FIGURE
1.
Comment The high incidence of detrusor areflexia in the present study is consistent with the findings of Rosomoff et al.’ This phenomenon is probably due to compressive damage of the efferent parasympathetic nerves supplying the detrusor muscle. Whether this impairment of the bladder innervation is reversible or irreversible has been debated in the literature. Several authors1*4,5 found total regression of the bladder disturbances after laminectomy and removal of the protruded disks, whereas Scott2 could not demonstrate any improvement in bladder function in his patients, although the follow-up period was six years in 1 of his cases. Our findings of detrusor areflexia in the majority of the patients
96
with previous laminectomies support the hypothesis that some of the neurogenic bladder disturbances in cauda equina injury due to protruded disk are irreversible. Impaired function of the striated external sphincter was found in only 2 of our patients, suggesting that involvement of the pudendal nerve roots is a relatively rare phenomenon in protrusion in intervertebral disks. However, the findings of prolonged signal transit times in the spinal evoked responses are strongly suggestive of impaired segmental innervation of the bladder and urethra. Urinary retention has been reported as the only symptom in patients with protruded lumbar disk, in which myelography apparently was normal.4 This is consistent with our findings of detrusor areflexia in 3 patients with normal myelograms. Therefore, the presence of detrusor areflexia as a sign of detrusor denervation may be utilized in the indication for surgery, when a protruded lumbar disk is the suspected cause of neurogenic bladder dysfunction. Box 295 Mayo Memorial Building Minneapolis, Minnesota 55455 (DR. BRADLEY) References 1. ROSOMOFF,H. L., et al. : Cystometry in the evaluation of nerve root compression in the lumbar spine, Surg. Gynecol. Obstet. 117: 263 (1963). 2. SCOTT, P. J.: Bladder paralysis in cauda equina lesions from disc prolapse, J. Bone Joint Surg. 47: 224 (1965). 3. HASAERTS,Ft., and BRIHAYE, J.: Syndrome de la queue de cheval par hemie discale, Acta Neurol. Psychiat. Belg. 58: 247 (1958). 4. LOVE, J. G., and EMMETT, J. L.: “Asymptomatic” protruded lumbar disk as a cause of urinary retention: preliminary report, Mayo Clin. Proc. 42: 249 (1967). 5. EMMETT, J. L., and LOVE, J. G.: Urinary retention in women caused by asymptomatic protruded lumbar disk: report of 5 cases, J. Urol. 99: 597 (1968). 6. BRADLEY, W. E., TIMM, G. W., and SCOTT, F. B.: Cystometry I, Urology 5: 424 (1975). 7. BRADLEY, W. E., SCOTT, F. B., and TIMM, G. W. : Sphincter electromyography, Urol. Clin. North Am. 1: 1 (1974). 8. BRADLEY, W. E.: Urethral electromyelography, J. Urol. 108: 563 (1972). 9. VON GARRELTS, B.: Analysis of micturition. A new method of recording the voiding of the bladder, Acta Chir. Stand. 112: 326 (1956).
UROLOGY ,/ JULY 1976 /
VOLUME VIII, NUMBER 1
BLADDER
DYSFUNCTION
IN
LUMBAR DISK AND
AFTER LAMINECTOMY JENS T. ANDERSEN, WILLIAM
M.D.
E. BRADLEY,
M.D.
From the Department of Urology H, Gentofte Hospital, University of Copenhagen, Denmark, and Department of Neurology University of Minnesota, Minneapolis, Minnesota
ABSTRACT-Bladder and urethral innervation was studied in 18 patients with protruded lumbar disk or persistent back pain after laminectomy. A high incidence of neurogenic dysfunction of the detrusor muscle was found, whereas impaired function of the striated external urethral sphincter was rare. The lesions were encountered among the patients with protruded lumbar disk as well as among the patients with sequelae after laminectomy, suggesting that neurogenic bladder dysfunction in cauda equina injury due to protruded disk is often irreversible.
Neurogenic dysfunction of the urinary bladder due to nerve root compression from disk prolapse has been documented in the literature.lm5 However, these reports deal only with the cystometric findings in this disease. In the present study bladder and urethral innervation was studied in 18 patients with protruded lumbar disk or persistent back pain after laminectomy using cyssphincter electromyography,7 electometry, tromyelography,* and flowmetry.g We found a high incidence of disturbances in detrusor innervation, whereas neurogenic dysfunction of the striated external urethral sphincter was rare. The lesions were encountered in the patients with protruded lumbar disk as well as among those with sequelae after laminectomy for herniated disk. Methods Detrusor function was studied by means of gas cystometry.’ The patients were catheterized with an indwelling urethral catheter. The bladder was emptied and inflated with carbon dioxide at a constant rate of 200 cc. per minute. Intravesical pressure was recorded with a transducer and
94
amplifier calibrated in centimeters of water, and the pressure curves were displayed on one channel of a two-channel strip chart recorder. Sphincter function was studied recording anal sphincter activity utilizing electronic integration.’ By simultaneous recording of the electromyographic activity in the periurethral striated sphincter and the anal sphincter, we found that anal sphincter activity was similar to the concurrent activity in the striated urethral sphincter during bladder filling and detrusor reflex contraction. A bipolar concentric electromyographic recording electrode mounted on a Teflon, hourglass-shaped anal plug was inserted in the anal canal. Electromyographic activity was recorded simultaneously with the cystometrogram on the second channel of the strin chart recorder. The electromyographic potentials were integrated and recorded in arbitrary units. Voluntary control of the sphincter mechanism was tested asking the patients to contract and relax the anal sphincter. The spinal micturition reflex arc was studied by recording of spinal evoked potentials.* For assessment we used specially designed urethral
UROLOGY
/ JULY 1976
/ VOLUME
VIII,
NUMBER
1
TABLE
I.
Myelographic findings in 18 patients with lower back pain
No. of Patients
Level of Defect* Group I L3-4 L4-5 L&
-
3 2 3
Sphincter
8
TOTAL Group II
1
L-3 b,.,block
(arachnoiditis) h-s block L+~ block (arachnoiditis) Normal
1 1 1
-
6
10
TOTAL *Intervertebral
space.
catheters with two circular stimulation electrodes mounted in a position adjacent to the proximal urethra with the catheter inserted. Electrical stimulation of the posterior urethra or the intrinsic bladder wall evokes a contractile response in the anal sphincter. The evoked electromyographic responses were recorded from the anal sphincter and cyclically averaged. The latency or signal transit time of the reflex was measured on the graphs. Flowmetry was performed according to the method described by Von Garrelts.g Furthermore, myelography was performed in all 18 patients. Results Eighteen patients, 15 females and 3 males, were studied. The mean age was 39.7 years with a range of twenty-one to seventy-two years. Eight of the patients (Group I) had lower back pain due to protruded lumbar intervertebral disks and had not undergone previous back surgery, whereas the remaining 10 patients (Group II) had previous laminectomies because of herniated disks, and now presented persistent lower back pain. The myelographic findings in the 2 groups are listed in Table I. C ystometric
findings
All the patients with myelographic documented protruded lumbar disks without previous surgery had detrusor areflexia. We defined detrusor areflexia by a cystometrogram showing absence of detrusor reflex even when the bladder was distended to the point of sensory discomfort. In the group of patients with previous
UROLOGY
/ lULY1976 / VOLUMEVIII,
NUMBER
laminectomies, 7 patients had detrusor areflexia, whereas 3 patients had normal detrusor function. These 3 patients with normal cystometrograms had normal myelograms, but 3 of the patients with detrusor areflexia also presented normal myelograms.
1
electromyographic
results
Sixteen of the patients had a normal sphincter electromyogram indicating full voluntary control of the periurethral striated sphincter. One patient demonstrated a flaccid external sphincter with no recordable electromyographic activity during bladder filling and loss of the ability to contract or relax the sphincter on command. This patient had a myelogram demonstrating a protruded disk in the third to fourth lumbar interspace. Finally, 1 patient had detrusor sphincter dyssynergia. This syndrome was defined by a sphincter electromyogram showing increasing clonic sphincter contraction evoked by bladder distention, where the increased sphincter activity could not: be depressed voluntarily by the patient.’ Further, the patient was unable to contract the sphincter on command. This patient had a protruded disk at the fourth to fifth lumbar interspace. Spinal evoked responses were studied in 15 of the patients. The signal transit time in healthy volunteers has been reported in the range of 50 to 70 msec.8 In 1 patient no response could be elicited in the anal sphincter by electrical stimulation of the proximal urethra indicating a block of the reflex arc. This patient, furthermore, showed a flaccid sphincter on the sphincter electromyogram. The signal transit times in the remaining 14 patients had a mean value of 75.7 msec. with a range of 40 to 100 msec. However, 9 of these patients had latencies longer than 70 msec. indicating impairment of the segmental innervation of the bladder and urethra.
Flowmetry
results
Uroflowmetry was performed in 17 of the patients. Two patients were not able to void during the investigation. The maximum flow values in the remaining 15 patients had a mean of 23 cc. per second with a range of 3 to 50 cc. per second. Seven of the patients had maximum flow values lower than 15 cc. per second. The average flow values had a mean of 7.3 cc. per second (range: 1 to 22.4 cc. per second). Postvoiding residual volumes were obtained from 15 patients, and the residual volumes had a mean of 94.2 cc. ranging from 0 to 475 cc.
95
S ymptomatology The principal urinary bladder symptoms are shown in Figure 1. Straining and the subjective feeling of urinary retention were the symptoms most frequently encountered, and these symptoms were correlated to detrusor areflexia in the cystometric recordings. The 2 patients complaining of urinary frequency had normal cystometrograms and a normal sphincter electromyogram. Only 1 patient had urinary infection. URINARY BLADDER
NUMBER
OF PATIENTS
SYMPTOMS
STRAINING I RETENTION
.,.
OVERFLOW. INCONTINENCE
FREQUENCY
,.,I;,
1
0 8
, I
:.: ;
p I
I ; I
I
I
!zz[ I
I I
t I L 8 I
I 8 1
I
,
8 ,
I I
,
URGENCY
Urinary bladder symptoms in 18 patients with protruded lumbar disk or sequelae after laminectomy. FIGURE
1.
Comment The high incidence of detrusor areflexia in the present study is consistent with the findings of Rosomoff et al.’ This phenomenon is probably due to compressive damage of the efferent parasympathetic nerves supplying the detrusor muscle. Whether this impairment of the bladder innervation is reversible or irreversible has been debated in the literature. Several authors1*4,5 found total regression of the bladder disturbances after laminectomy and removal of the protruded disks, whereas Scott2 could not demonstrate any improvement in bladder function in his patients, although the follow-up period was six years in 1 of his cases. Our findings of detrusor areflexia in the majority of the patients
96
with previous laminectomies support the hypothesis that some of the neurogenic bladder disturbances in cauda equina injury due to protruded disk are irreversible. Impaired function of the striated external sphincter was found in only 2 of our patients, suggesting that involvement of the pudendal nerve roots is a relatively rare phenomenon in protrusion in intervertebral disks. However, the findings of prolonged signal transit times in the spinal evoked responses are strongly suggestive of impaired segmental innervation of the bladder and urethra. Urinary retention has been reported as the only symptom in patients with protruded lumbar disk, in which myelography apparently was normal.4 This is consistent with our findings of detrusor areflexia in 3 patients with normal myelograms. Therefore, the presence of detrusor areflexia as a sign of detrusor denervation may be utilized in the indication for surgery, when a protruded lumbar disk is the suspected cause of neurogenic bladder dysfunction. Box 295 Mayo Memorial Building Minneapolis, Minnesota 55455 (DR. BRADLEY) References 1. ROSOMOFF,H. L., et al. : Cystometry in the evaluation of nerve root compression in the lumbar spine, Surg. Gynecol. Obstet. 117: 263 (1963). 2. SCOTT, P. J.: Bladder paralysis in cauda equina lesions from disc prolapse, J. Bone Joint Surg. 47: 224 (1965). 3. HASAERTS,Ft., and BRIHAYE, J.: Syndrome de la queue de cheval par hemie discale, Acta Neurol. Psychiat. Belg. 58: 247 (1958). 4. LOVE, J. G., and EMMETT, J. L.: “Asymptomatic” protruded lumbar disk as a cause of urinary retention: preliminary report, Mayo Clin. Proc. 42: 249 (1967). 5. EMMETT, J. L., and LOVE, J. G.: Urinary retention in women caused by asymptomatic protruded lumbar disk: report of 5 cases, J. Urol. 99: 597 (1968). 6. BRADLEY, W. E., TIMM, G. W., and SCOTT, F. B.: Cystometry I, Urology 5: 424 (1975). 7. BRADLEY, W. E., SCOTT, F. B., and TIMM, G. W. : Sphincter electromyography, Urol. Clin. North Am. 1: 1 (1974). 8. BRADLEY, W. E.: Urethral electromyelography, J. Urol. 108: 563 (1972). 9. VON GARRELTS, B.: Analysis of micturition. A new method of recording the voiding of the bladder, Acta Chir. Stand. 112: 326 (1956).
UROLOGY ,/ JULY 1976 /
VOLUME VIII, NUMBER 1
