- Email: [email protected]
Relationship of urethral length and anterior wall relaxation to urinary stress incontinence
Relationship of urethral length and anterior wall relaxation to urinary stress incontinence R.
P.
BECK,
M.D.,
NORA
HSU.
M.D.
Montreal,
Quebec,
C’anadrr
C.M.,
M.R.C.O.G.,
7’ II 1,; I’ u R P o s E of this paper is to report results in one area of a combined investigation of urinary stress incontinence in the I)epartment of Obstetrics and Gynaecology, Royal Victoria Hospital, Montreal. Our interest in the correlation between urethral length and anterior wall relaxation and urinary stress incontinence has been stimulated by divergent reports in the literature about these relationships. Low,” Francis and Jeffcoate,’ and Hodgkinson and associates’ have reported no correlation between urethral length and stress incontinence. Lapides and associates’ have reported that a shortened urethra (in the standing position) is the most frequent basic cause of stress incontinence. They reached this conclusion after comparing 35 continent with 22 stress incontinent patients. Gardiner and co-workers,” using radiographic measurement of urethral len,gth, have supported Lapides’ theory. The relationship of anterior vaginal wall rrlaxation to urinary stress incontinence has also been controversial. In 1960, Jeffcoate’ dogmatically stated that “stress incontinence From the Department Gynaecology, McGill Royal Victoria Hospital.
of
Thir work the Medical
by a grant from C’ouvcil of Canadn.
umr tupported Rr\enrch
Obstetrics llnimrsity
F.A.C.S.,
F.R.C.S.(C)
is not a symptom of genital prolapse, indeed it has no connection with it.” %Jeffcoate’ has also reported that only 40 per cent of his cystocele-urethrocele population had stress incontinence, that incidence being no greater than the incidence in an otherwise Jimilar population. Newman and Northup” found that 59 per cent of their patients with a cystocele had stress incontinence. Low’ teported that 16 per cent of 130 patients with stress incontinence had no demonstrable anterior vaginal wall relaxation, and that -l8 per cent of the same ,group had only slight anterior wall relaxation. ‘I’he latter author concluded that anterior wall relaxation is not the anatomical cause of stress incontinence. Materials
and
methods
Fifty patients who failed to demonstrate stress incontinence with a bladder load of 200 C.C. of normal saline while in the standing or lithotomy position formed a group of normal patients without incontinence. A bladder load of 200 C.C. saline was used because with that amount of fluid in the bladder the intravesical pressure is about equal to intra-abdominal pressure.’ Fifty-Sk patients who demonstrated stress incontinence in the lithotomy position with a bladder load of 200 cc. saline constituted
and and
738
Urethra
the stress incontinence group for comparison. In both groups the urethral length was measured in a resting lithotomy position. The loading volume of saline was introduced into the bladder of the patient at body temperature through a No. 16 Foley catheter with a 5 C.C. balloon. The balloon was pulled down snugly against the bladder neck, and the level of the external meatus was noted on the catheter. The urethral length was measured from the latter point to the commencement of the collapsed balloon to the nearest millimeter. Se\;enty-one consecutive patients seen in the gynecological outpatient clinic with varying degrees of anterior wall relaxation were tested for stress incontinence. None of these patients had previously been tested in our stress incontinence project. These patients were not asked whether or not they had stress incontinence until they had been tested For that sign. These patients were divided into three groups: those with urethrocele only, with cystocele only, and with cystourethvocele. Crethrocele was diagnosed when redundancy of the lower (distal) 2.5 cm. of the anterior vaginal wall was noted with the patient at rest in the lithotomy position. Cystocelc was diagnosed when bulging of the anterior vaginal wall proximal to the lower 2.5 cm. was noted with the patient in the lithotomy position. An attempt was made to grade the cystocele according to the degree of prolapse, with recognition of the difficulty and inaccuracy involved. Grade I. Bulging of the “bladder portion” of the anterior wall at rest but not down to the inferior edge of the symphysis pubis. Grade II. Bulging down to the inferior edge of the symphysis pubis with straining. Grade III. Bulging to the same level as Grade II at rest. Grade IV. Bulging beyond the introitus with straining. Grade V. Bulging to the rstent of Grade IV at rest. In grading the degree of rystocele there was overlap especially of Grade III and Grade IV types in some instances. In such
and
stress
Table I. Urethral length incontinent patients Urethral
length
in normal
(No.)
(No.)
1 2 6 14 13 12 2
0 0 8 19 21 7 1
50 3.2
56 3.2
length
Table II. Cystocele stress incontinence prolapse
only cases correlated according to degree
Cystoc Grade
and stress
Strm incontinent
(cm.)
urethral
739
NOVd coutinent
Less than 1.5 1.6 to 2.0 2.1 to 2.5 2.6 to 3.0 3.1 to 3.5 3.6 to 1.0 1.1 to 4.5 Total Average
incontinence
ele
Stress
(No.)
with of
incontinent (No.1
I II III IV V
17 10
0 3
5
2
4
1
Total
37
1
1 7
Table III. Cystocele and urethrocele cases showing correlation with stress incontinence according to degree of prolapse Grade
Cystourethrocele (No.)
Stress
imontinent (No.1
I II III IV V
5
‘l
9
9
6 8 5
5 6 5
Total
33
29
cases the cystocele grading was advanced to the higher grade. The same patients then had the bladders emptied by catheterization and loaded with 200 C.C. of saline. They were then asked to cough repeatedly in the lithotomy and erect positions and were classed as stress incontinent if a spurt of urine was lost in either position.
740
Beck
and
Hsu
Results
Table I shows the comparison of urethral length in 0.5 cm. groupings in patients without incontinence and with stress incontinence. The average urethral length in the two groups was exactly the same: 3.2 cm. The urethral length \-aried from 1.4 to 4.5 cm. in the continent group and from 2.1 to 4.2 cm. in the stress incontinent group. Only 1 patient had urethrocele without cystocele; she demonstrated stress incontinence. A previous anterior colporrhaphy had been performed in this case. Thirty-seven patients had some degree of cystocelc without urcthrocele. Table II shows cystocele grading in this group correlated with demonstrable stress incontinence. Seven of the 37 patients showed stress incontinence. Thirty-three patients showed cystocelc plus urethrocelc. Table III shows cystocele grading in this group correlated with stress incontinence. Twenty-nine of the 33 patients showed stress incontinence. Commeni
From our results compiled in Table I there appears to be no correlation between shortened urethral length and stress incontinence. It should be emphasized that our urethral measurements were taken with the patient in the lithotomy position. However all the patients in the stress incontinent group lost urine in the lithotomy position, so urethral length, per se, is not related to stress incontinence. We have observed te!escoping of the urethra as described by Lapides and associates.’ and we believe that this shortening of the urethra is caused by poor periurethral and bladder neck support. This poor support. rather than shortening of thf urethra. is in our opinion the cause of the stress incontinence. There was a very high incidence of stress incontinence (90 per cent) in patients with either urethrocele alone (I case) or with urethrocele plus cystoccle (33 cases). The incidence of stress incontinence was low (19 per cent) when cystocele existed without urethrocele. The over-all incidence of stress incontinence in our clinic is about 30 per
cent. Urethrocele, reflecting poor periurethral and bladder neck support, appears to be the key anatomic defect associated with stress incontinence. Poor peGurethra and bladder neck support cause stress incontinence in over 98 per cent of cases. bccauscx they crcatr an unfavorable balance b:‘twc(‘n intraurethral and intravesical pressurr.’ Youssef”’ has obser\.ed that the dcgrcr oi anterior wall relaxation is no index to the, se\,crity of stress incontinencr.. Kevicw ol Tables II and III shows that there is 11~1 correlation between degree of anterior wall relaxation and the frequency with which stress incontinence occurred. It is not surprising to read in Low’s’ report that 48 1”~ cent of 137 patients with stress incontinent had only sli,qht anterior wall rclasatioll. From our pressure studies’ M‘Y know that low intraurethral pressure resulting from poor periurcthral support can br associatfxd with very little anterior wall relaxation. We think that the low inciclence of stress incontinence in the “cystocele only” group is caused by kinkin,q of the lIpper ILvethra and bladder neck as the hladdrr bulges down with cough. This kinking products an eff’cbctive intraurethral pressure which resists the, increased intravesical prcxu~~r.~ We agrc’c with Jeffcoate” that patients with prociclc~ntia uncornrnonly have stress incontinence. The explanation for this observation is that usually there is s\&Ficirnt support along the urethra at some point to causc~ a kinking of the urethra as the bladder and upper urethra descend with cough. This ltinkinq of thts urethra can produce enough intraur&ral pressure to maintain c0ritinence.l Summary
1. Stress incontinence is not caused by a shortened urethra. 2. Urethroccle 01 cystourethrocelc arr associattad with a 90 per cent incidence oi stress incontinence whereas cystocele devclopment alon? is associated with a lo\\ incidence of stress incontinence. 3. There is no positive correlation between the degree of anterior wall relaxation and the freyuency of stress incontinence.
Urethra
and
stress
incontinence
741
REFERENCES
1. 3*.
3.
1.
5.
Beck,
R.
OBST.
& GYNEC.
P.,
and
Maughan, G. B.: AM. J. (In press.) Francis, W. J. A.. and Jeffcoate, T. N. A.: In Kellar, R. J., editor: Modern Trends in Gynaecology, London, 1963, Butterworth & Co., Ltd., vol. 3, p. 72. Gardiner, S. H.. Campbell, J. A., Garrett, R. A., and Schell, H. R.: AM. J. OBST. & GYNE~. 68: 1112, 1961. Hodgkinson, C. P., Drukkcr, B. H., and Hershey, G. J. C.: AM. J. OBST. & GYXEC. 86: 16. 1963. Jeffcoatc, T. N. A.: J. Roy. Coil. Surgeons Edinburgh 7: 28, 1961.
6.
7.
8.
9. 10.
Jeffcoate, T. N. A., and Roberts, H.: J. Obst. & Gynaec. Brit. Emp. 59: 685, 1952. Lapides, J., Ajemian, E. P.. Lichtwardt, J. B. A.: Surg. Gynrc. & R., and Brrakcy, Obst. 111: 224, 1960. Low. J. A.: AM. J. OBST. & Gn-EC. 88: 322, 1964. Newman, H. F., and Northup, J. D.: Am. J. Surg. 102: 633, 1961. Youssef. A. F.: Gynecological Urology. Springfield, Illinois, 1961, Charles C Thomas. Publisher, pp. 300 and 358.
P.
BECK,
M.D.,
NORA
HSU.
M.D.
Montreal,
Quebec,
C’anadrr
C.M.,
M.R.C.O.G.,
7’ II 1,; I’ u R P o s E of this paper is to report results in one area of a combined investigation of urinary stress incontinence in the I)epartment of Obstetrics and Gynaecology, Royal Victoria Hospital, Montreal. Our interest in the correlation between urethral length and anterior wall relaxation and urinary stress incontinence has been stimulated by divergent reports in the literature about these relationships. Low,” Francis and Jeffcoate,’ and Hodgkinson and associates’ have reported no correlation between urethral length and stress incontinence. Lapides and associates’ have reported that a shortened urethra (in the standing position) is the most frequent basic cause of stress incontinence. They reached this conclusion after comparing 35 continent with 22 stress incontinent patients. Gardiner and co-workers,” using radiographic measurement of urethral len,gth, have supported Lapides’ theory. The relationship of anterior vaginal wall rrlaxation to urinary stress incontinence has also been controversial. In 1960, Jeffcoate’ dogmatically stated that “stress incontinence From the Department Gynaecology, McGill Royal Victoria Hospital.
of
Thir work the Medical
by a grant from C’ouvcil of Canadn.
umr tupported Rr\enrch
Obstetrics llnimrsity
F.A.C.S.,
F.R.C.S.(C)
is not a symptom of genital prolapse, indeed it has no connection with it.” %Jeffcoate’ has also reported that only 40 per cent of his cystocele-urethrocele population had stress incontinence, that incidence being no greater than the incidence in an otherwise Jimilar population. Newman and Northup” found that 59 per cent of their patients with a cystocele had stress incontinence. Low’ teported that 16 per cent of 130 patients with stress incontinence had no demonstrable anterior vaginal wall relaxation, and that -l8 per cent of the same ,group had only slight anterior wall relaxation. ‘I’he latter author concluded that anterior wall relaxation is not the anatomical cause of stress incontinence. Materials
and
methods
Fifty patients who failed to demonstrate stress incontinence with a bladder load of 200 C.C. of normal saline while in the standing or lithotomy position formed a group of normal patients without incontinence. A bladder load of 200 C.C. saline was used because with that amount of fluid in the bladder the intravesical pressure is about equal to intra-abdominal pressure.’ Fifty-Sk patients who demonstrated stress incontinence in the lithotomy position with a bladder load of 200 cc. saline constituted
and and
738
Urethra
the stress incontinence group for comparison. In both groups the urethral length was measured in a resting lithotomy position. The loading volume of saline was introduced into the bladder of the patient at body temperature through a No. 16 Foley catheter with a 5 C.C. balloon. The balloon was pulled down snugly against the bladder neck, and the level of the external meatus was noted on the catheter. The urethral length was measured from the latter point to the commencement of the collapsed balloon to the nearest millimeter. Se\;enty-one consecutive patients seen in the gynecological outpatient clinic with varying degrees of anterior wall relaxation were tested for stress incontinence. None of these patients had previously been tested in our stress incontinence project. These patients were not asked whether or not they had stress incontinence until they had been tested For that sign. These patients were divided into three groups: those with urethrocele only, with cystocele only, and with cystourethvocele. Crethrocele was diagnosed when redundancy of the lower (distal) 2.5 cm. of the anterior vaginal wall was noted with the patient at rest in the lithotomy position. Cystocelc was diagnosed when bulging of the anterior vaginal wall proximal to the lower 2.5 cm. was noted with the patient in the lithotomy position. An attempt was made to grade the cystocele according to the degree of prolapse, with recognition of the difficulty and inaccuracy involved. Grade I. Bulging of the “bladder portion” of the anterior wall at rest but not down to the inferior edge of the symphysis pubis. Grade II. Bulging down to the inferior edge of the symphysis pubis with straining. Grade III. Bulging to the same level as Grade II at rest. Grade IV. Bulging beyond the introitus with straining. Grade V. Bulging to the rstent of Grade IV at rest. In grading the degree of rystocele there was overlap especially of Grade III and Grade IV types in some instances. In such
and
stress
Table I. Urethral length incontinent patients Urethral
length
in normal
(No.)
(No.)
1 2 6 14 13 12 2
0 0 8 19 21 7 1
50 3.2
56 3.2
length
Table II. Cystocele stress incontinence prolapse
only cases correlated according to degree
Cystoc Grade
and stress
Strm incontinent
(cm.)
urethral
739
NOVd coutinent
Less than 1.5 1.6 to 2.0 2.1 to 2.5 2.6 to 3.0 3.1 to 3.5 3.6 to 1.0 1.1 to 4.5 Total Average
incontinence
ele
Stress
(No.)
with of
incontinent (No.1
I II III IV V
17 10
0 3
5
2
4
1
Total
37
1
1 7
Table III. Cystocele and urethrocele cases showing correlation with stress incontinence according to degree of prolapse Grade
Cystourethrocele (No.)
Stress
imontinent (No.1
I II III IV V
5
‘l
9
9
6 8 5
5 6 5
Total
33
29
cases the cystocele grading was advanced to the higher grade. The same patients then had the bladders emptied by catheterization and loaded with 200 C.C. of saline. They were then asked to cough repeatedly in the lithotomy and erect positions and were classed as stress incontinent if a spurt of urine was lost in either position.
740
Beck
and
Hsu
Results
Table I shows the comparison of urethral length in 0.5 cm. groupings in patients without incontinence and with stress incontinence. The average urethral length in the two groups was exactly the same: 3.2 cm. The urethral length \-aried from 1.4 to 4.5 cm. in the continent group and from 2.1 to 4.2 cm. in the stress incontinent group. Only 1 patient had urethrocele without cystocele; she demonstrated stress incontinence. A previous anterior colporrhaphy had been performed in this case. Thirty-seven patients had some degree of cystocelc without urcthrocele. Table II shows cystocele grading in this group correlated with demonstrable stress incontinence. Seven of the 37 patients showed stress incontinence. Thirty-three patients showed cystocelc plus urethrocelc. Table III shows cystocele grading in this group correlated with stress incontinence. Twenty-nine of the 33 patients showed stress incontinence. Commeni
From our results compiled in Table I there appears to be no correlation between shortened urethral length and stress incontinence. It should be emphasized that our urethral measurements were taken with the patient in the lithotomy position. However all the patients in the stress incontinent group lost urine in the lithotomy position, so urethral length, per se, is not related to stress incontinence. We have observed te!escoping of the urethra as described by Lapides and associates.’ and we believe that this shortening of the urethra is caused by poor periurethral and bladder neck support. This poor support. rather than shortening of thf urethra. is in our opinion the cause of the stress incontinence. There was a very high incidence of stress incontinence (90 per cent) in patients with either urethrocele alone (I case) or with urethrocele plus cystoccle (33 cases). The incidence of stress incontinence was low (19 per cent) when cystocele existed without urethrocele. The over-all incidence of stress incontinence in our clinic is about 30 per
cent. Urethrocele, reflecting poor periurethral and bladder neck support, appears to be the key anatomic defect associated with stress incontinence. Poor peGurethra and bladder neck support cause stress incontinence in over 98 per cent of cases. bccauscx they crcatr an unfavorable balance b:‘twc(‘n intraurethral and intravesical pressurr.’ Youssef”’ has obser\.ed that the dcgrcr oi anterior wall relaxation is no index to the, se\,crity of stress incontinencr.. Kevicw ol Tables II and III shows that there is 11~1 correlation between degree of anterior wall relaxation and the frequency with which stress incontinence occurred. It is not surprising to read in Low’s’ report that 48 1”~ cent of 137 patients with stress incontinent had only sli,qht anterior wall rclasatioll. From our pressure studies’ M‘Y know that low intraurethral pressure resulting from poor periurcthral support can br associatfxd with very little anterior wall relaxation. We think that the low inciclence of stress incontinence in the “cystocele only” group is caused by kinkin,q of the lIpper ILvethra and bladder neck as the hladdrr bulges down with cough. This kinking products an eff’cbctive intraurethral pressure which resists the, increased intravesical prcxu~~r.~ We agrc’c with Jeffcoate” that patients with prociclc~ntia uncornrnonly have stress incontinence. The explanation for this observation is that usually there is s\&Ficirnt support along the urethra at some point to causc~ a kinking of the urethra as the bladder and upper urethra descend with cough. This ltinkinq of thts urethra can produce enough intraur&ral pressure to maintain c0ritinence.l Summary
1. Stress incontinence is not caused by a shortened urethra. 2. Urethroccle 01 cystourethrocelc arr associattad with a 90 per cent incidence oi stress incontinence whereas cystocele devclopment alon? is associated with a lo\\ incidence of stress incontinence. 3. There is no positive correlation between the degree of anterior wall relaxation and the freyuency of stress incontinence.
Urethra
and
stress
incontinence
741
REFERENCES
1. 3*.
3.
1.
5.
Beck,
R.
OBST.
& GYNEC.
P.,
and
Maughan, G. B.: AM. J. (In press.) Francis, W. J. A.. and Jeffcoate, T. N. A.: In Kellar, R. J., editor: Modern Trends in Gynaecology, London, 1963, Butterworth & Co., Ltd., vol. 3, p. 72. Gardiner, S. H.. Campbell, J. A., Garrett, R. A., and Schell, H. R.: AM. J. OBST. & GYNE~. 68: 1112, 1961. Hodgkinson, C. P., Drukkcr, B. H., and Hershey, G. J. C.: AM. J. OBST. & GYXEC. 86: 16. 1963. Jeffcoatc, T. N. A.: J. Roy. Coil. Surgeons Edinburgh 7: 28, 1961.
6.
7.
8.
9. 10.
Jeffcoate, T. N. A., and Roberts, H.: J. Obst. & Gynaec. Brit. Emp. 59: 685, 1952. Lapides, J., Ajemian, E. P.. Lichtwardt, J. B. A.: Surg. Gynrc. & R., and Brrakcy, Obst. 111: 224, 1960. Low. J. A.: AM. J. OBST. & Gn-EC. 88: 322, 1964. Newman, H. F., and Northup, J. D.: Am. J. Surg. 102: 633, 1961. Youssef. A. F.: Gynecological Urology. Springfield, Illinois, 1961, Charles C Thomas. Publisher, pp. 300 and 358.