Urinary incontinence due to lumbar spinal stenosis causing disability and lowering quality of life

1. Background

Lumbar spinal stenosis (LSS) is a condition where the spinal canal, intervertebral foramena and lateral processes are narrowed. The reduction of the volume of the canal causes pressure on dural sac and nerve roots [1, 2, 3, 4, 5]. Patients suffer from low back and leg pain, nerogenic claudication, motor and sensory loss and from urinary bladder disfunctions. The neural mechanisms regulating the control of the bladder are complex, and they are also prone to various damage and disorders [6].

Urinary incontinence is a condition that has significant psychological and social implications. It is a very common disorder, as it affects more than 5% of the world population. It is most common in women over 65 years of age. As the whole spectre of the condition is difficult to study, there are no exhaustive epidemiological data that would depict the global incidence of the disorder [7, 8, 9]. In current literature there is insufficienmt information regarding urinary incontinence in women suffering from LSS.

2. Objectives

The aim of the study was to assess the frequency and scale of urinary incontinence in female patients with pain in course of lumbar spinal canal stenosis, as well as to evaluate the risk factors and the quality of life of patients.

The study was conducted among patients hospitalized at the Spine Surgery Department. The study population consisted of 50 women aged 33 to 83 years old, mean age 55.32 ± 12.97 years, diagnosed with low back and leg pain due lumbar spinal stenosis. The clinical control group consisted of 30 women without spinal disorders, aged 36 to 78 years, mean age 54.87 ± 12.01 years. There was no statistically significant age difference between the two groups.

The criterion for subject inclusion in the study was the diagnosis of lumbar spinal canal stenosis based on seven history items: leg or buttock pain while walking, flexion forward relieved the symptoms, relief when using a shopping cart or bicycle, motor or sensory disturbance while walking, normal and symmetric foot pulses, lower extremity weakness, and low back pain as well as imaging methods: X-ray and MRI [10]. The AP diameter of spinal canal was below 15 mm, and frontal below 25 mm. The patients expressed informed consent to participate in the study.

The criteria for excluding patients were: diagnosis of spine disorders other than stenosis, other disorders of the neural system, urinary system and serious internal diseases.

The consent to conduct the study was obtained from the director of the hospital, the head of the Ward of Spine Surgery and the University Ethic Commission.

Biometric data for the patients with stenosis and for the clinical control group were presented in Table 1, and employment activity in Table 2.

Patients concerns and doubts while filling all questionnaires were explained by physiotherapist. We used an anonymous questionnaire devised by authors, as well as Oswetry Disability Index (ODI), International Consultation on Incontinence Questionnaire Urinary Incontinence Short Form (ICIQ-UI-SF), and International Consultation on Incontinence Questionnaire Urinary Incontinence Quality of Life Module (ICIQ-LUTSqol). The questionnaire concerning patients functioning and symptoms severity was based on McKenzie examination [11, 12, 13, 14].

For the study, we used two modules of questionnaires of International Consultation on Incontinence Forum of the World Health Organisation (WHO). The questionnaires were fully accepted and recommended by WHO. The consent for their use was obtained on behalf of the ICIQ analytical group. The questionnaires are useful for comprehensive assessment of symptoms and the degree to which urinary incontinence affects everyday life of the patient. They may be universally used for both clinical practice and scientific studies [15].

International Consultation on Incontinence Questionnaire Urinary Incontinence Short Form (ICIQ-UI-SF) is a short questionnaire for obtaining comprehensive information on the intensity, influence on everyday functioning, and the perceived cause for urinary incontinence [14].

The patients who reported urinary incontinence in the questionnaire, filled out an additional form – International Consultation on Incontinence Questionnaire Urinary Incontinence Quality of Life Module (ICIQ-LUTSqol). The questionnaire was designed on the basis of King’s Health Questionnaire and consists of 20 questions that allow to assess the impact of urinary incontinence on everyday life, with particular regard to social effects [15].

4. Results

Patients suffered from chronic lumbar spinal canal stenosis for mean 18.3 ± 14.3 months. The average pain in VAS scale (0–10) was 7.16 ± 1.8, and their disability in ODI scale was 52.64 ± 13.80 (severe disability).

Neurological examination found superficial sensory deficits in 46 women (92%), and muscles atrophy in 44 women (88%), 38 women (76%) had positive SLR sign. Thirty-four patients (64%) had multi-segmental stenosis; of which in 9 patients (18%) stenosis occurred at L5–S1, in 7 patients (14%) at L4–L5, in 1 (2%) at L3–L4 and in 1 (2%) patient at L2–L3.

Analysis according to ICIQ-UI-SF urinary incontinence occurred in 28 women (56%) in the group with stenosis, as compared to 13 women (43%) from the clinical control group. Fifteen patients (30%) from the stenosis group suffered from urine leakage once a week or less frequent, compared to 8 subjects (27%) from the clinical control group. Eight patients (16%) had leakage twice or three times a week, compared to 3 women (10%) in the clinical control group. Six percent of women from both groups had leakage several times a day. None of the control group subjects had leakage more than ten times a day, compared with 2 patients (4%). None of the women, from neither of the group, reported constant leakage of urine.

Respondents were asked to assess the leakage volume: 23 (46%) patients defined it as small, and 5 (10%) patients defined it as moderate in contrast to the control group who defined the leakage volume as small.

Patients were asked to define on the VAS to what extent urinary incontinence disturbed their everyday life. The results obtained did not reveal any statistically significant differences between the groups as regards ICIQ-UI-SF point scoring questions. The total points scored on the test defines how serious urinary incontinence is. For the stenosis group the score was mean 4.8 ± 1.4 and in the control group the score was mean 2.9 ± 0.8. The difference between both groups showed a tendency towards statistical significance ( p = 0.089). Patients with stenosis reported significantly more frequent leakage without an obvious reason (Table 3).

Quality of life of patients with urinary incontinence was measured with ICIQ-LUTSqol. The results show statistically significant differences as regards the effect of urinary incontinence on contacts with other people ( p = 0.03), the nuisance of feeling constantly tired and emotional exhaustion related to the disorder ( p = 0.03), as well as the general effect of urinary incontinence on everyday life ( p = 0.03) between the two groups.

The mean total number of points was 57.28 in the study group and 40.2 in the control group. The Kendall rank correlation coefficient revealed strong significant correlation between the total score of ICIQ-UI-SF and final score of ICIQ-LUTSqol (tau = 0.719; 0.001). No statistically significant correlations were found between the results of both questionnaires and age, body mass, body height or BMI.

Patients had between 0 and 6 children. The highest scores in the questionnaires among the women in the study group were achieved by women who had three children (n = 11). The ICIQ-UI-SF average score was 8.73 points, while the ICIQ-LUTSqol score was 88.91. The Kendall rank correlation coefficient revealed a statistically significant correlation between the number of deliveries and the total score of ICIQ-UI-SF (tau = 0.271; p = 0.010) and ICIQ-LUTSqol (tau = 0.260; p = 0.009). Statistically significant correlation was found also between duration of the current pain syndrome and the total score of ICIQ-UI-SF (tau = ⁣ - 0.247; p = 0.012), ICIQ-LUTSqol (tau = ⁣ - 0.226; p = 0.014).

It was interesting to note that the correlation was negative, which means that the longer the pain was, the lesser was the problem of urinary incontinence. It is most likely related to the fact that in the acute phase of the disorder the nerve roots are more irritated, and urinary incontinence is a new and severe condition. Along with the course of the disorder the pain easies, and the patients get used to the situation and learn how to manage it.

The non-parametric Mann-Whitney U test for independent samples revealed a statistically significant correlation between the SLR sign and the total score in both questionnaires (for the sum 3 + 4 + 5 U = 105; p = 0.030 and for QOL U = 100.5; p = 0.021). Patients who had positive SLR sign had higher scores for both 3 + 4 + 5 sum and QOL sum than study population patients in who SLR sign was negative. Sciatic root irritation was more common in women with stress urinary incontinence. In the case of chronic stenosis, the SLR sign is usually negative, which seems to confirm the author’s thesis that stress urinary incontinence may be related to acute lumbar pain.

We did not find any statistically significant correlation between diagnosed muscle atrophy, superficial sensory deficits or the level of the spinal canal stenosis and the incontinence.

5. Discussion

Authors results showed that pain and neural involvement due to spinal canal stenosis caused decrease of quality of social life, sexual ability, travelling, sleeping, activities related to daily hygiene. Severe decrease of life quality was reported also by Truszczynska et al. in their study on patients with patients with spinal canal stenosis evaluated with SF-36 [16].

Numerous authors tried to define the frequency of urinary incontinence in population. Minisian et al. analyzed epidemiological data of 35 studies. They found that urinary incontinence affected a mean of 27.6% women and 10.5% men. A large study population may realistically represent the scale of the disorder [17]. Comparing their data with our own data we observed that in women with lumbar spinal canal stenosis urinary incontinence was more common than in the female population at large.

Urinary incontinence may be a symptom of a number of disorders related to the dysfunctions of the nervous system like cauda equine syndrome due to and lumbar disc herniation [18].

Tsai et al. studied symptoms of lower urinary tract in patients with spinal pain and sciatica. The study used the ODI scale, as well as American Urological Association Symptom Score (AUASS), which allows for collecting information on any continence disorders such as urinary incontinence, nocturnal enuresis, or intermittent stream of urine. In 67 patients (27.3%) AUASS score was high. In this group there were 5 patients diagnosed with spinal canal stenosis, 5 with nucleus pulposus hernia, while the rest suffered from other disorders. Correlations were found between the size of the spinal canal, as determined by MRI, and lower urinary tract symptoms. Surgical decompression resulted in improvement in both groups, the one with the higher and the one with the lower score on AUASS [6].

De Riggo et al. studied urinary incontinence in patients with degenerative spine disorders. Out of 214 patients 12.6% had urinary incontinence. Women and patients with radicular weakness were at a higher risk of developing urinary incontinence. Patients with urinary incontinence had significantly lower BMI than patients without this disorder. Similarly to us, De Riggo et al. did not find a correlation between age and incidence of urinary incontinence. The surgical treatment resulted in incontinence control in more than half of affected patients [19].

Perner et a.l conducted a study to check urinary incontinence in men who had low back pain with sciatica. 80% of patients with spinal canal stenosis had disorders of lower urinary tract. There was no correlation between age, level of the nerve root pressure or pain intensity on the VAS, and the disorders of lower urinary tract [20].

The results we obtained point at a significantly negative effect of urinary incontinence on contacts with people, troublesomeness it causes, the feeling of tiredness and emotional exhaustion, and its general impact on everyday life. Abrams et al. 2014 had similar results in their multi centre studies conducted on 1203 women aged 45 to 60 years. They found that urinary incontinence had direct impact on women’s quality of life and negatively affected their psychological state. The authors proposed three categories of urinary incontinence: slight (87%), medium (11%) and serious (2%). The mean results scored in ICIQ-UI-SF for the three groups were the following: minimal UI 7.9 ± 3.4, medium UI 13.8 ± 2.9 and serious UI 18.3 ± 3.9. Similar categories were proposed on the basis of ICIQ-LUTSqol scores: minimal UI 30.6 ± 7.3, medium UI 41.0 ± 11.2 and serious UI 56.9 ± 17.6. The results regarding psychological wellbeing of the subjects were lower, too. Sixteen (32%) out of 50 subjects had BMI ⩾ 30.0 [21]. In contrast to Burgio, whose study found a correlation between urinary incontinence and BMI regardless of age, no correlation between urinary incontinence and BMI was found [22].

In authors study pain intensity, level of spinal stenosis and disability caused by the disease did not correlate with incidence of urinary incontinence. The statistically significant correlation between SLR sign and high incidence of urinary incontinence might be related to the fact of additional narrowing of the spinal canal by disc herniation.

According to Richter et al. pregnancy and childbirth are among the most important risk factors for developing UI [23]. A single pregnancy and subsequent delivery significantly increase a woman’s risk for UI in later life [24, 25, 26, 27]. Our results confirm an increasing risk of developing urinary incontinence with the number of births.

Symptoms of lower urinary tract disorders including incontinence are reported by about 50% of patients with leg pain due to spinal stenosis. In some patients these symptoms may be neglected and assigned to primary urological disorder [28].

Common findings in LSS patients are underactive or a contractile detrusor, but detrusor overactivity is also found in 29% of patients. Therefore overflow or urge urinary incontinence (UUI) may follow [29, 30]. LSS can also lead to stress urinary incontinence (SUI) that will result from lack of resistance at the level of the external sphincter due to pelvic floor denervation [31]. Therefore symptoms of UI in women after pregnancies and deliveries could by magnified by disorders resulted from LSS.

Physiotherapy should play an important role in improving quality of life of the studied group of women. The physiotherapy should to a larger extent be focused on prevention of the disorder. There is a number of ways urinary incontinence may be treated through physiotherapy. The literature most often quotes electrical stimulation, pelvic floor muscle training, Electromyographic Triggered Stimulation (ETS) or bladder training. One needs to remember that the choice of therapy should depend on full diagnosis, including gynaecological examination [32]. Physiotherapist should remember to include in LSS treatment beside: abdominal muscles strengthening, iliopsoas and rectus femoris muscles stretching, spinal extensors relaxation, walking distance lengthening, usage of orthosis [16] also lifestyle interventions, bladder training, pelvic floor muscle training and electrical stimulation (34).

6. Conclusions

1.

Urinary incontinence in women with lumbar spinal canal stenosis is significantly different from the control group. They had more frequent and of higher volume urine leakages.