Definitions within this article conform to the standards recommended by the International Continence Society and International Children’s Continence Society, except where specifically noted. The focus of this case presentation is on a child with daytime urinary incontinence because of dysfunctional voiding.
Dysfunctional voiding is an intermittent and/or fluctuating urine flow rate because of involuntary intermittent contraction of the pelvic floor musculature during voiding, in neurologically normal individuals.
Urinary incontinence is the uncontrollable leakage of urine and can be diurnal (daytime) or enuresis (incontinence while sleeping, also referred to as “bed wetting”). Dysfunctional voiding and incontinence in children can increase emotional, psychological, and social stress for the child as well as their family members.
The pelvic floor consists of different layers of muscle and other tissues. The most cranial layer is the peritoneum of the pelvic viscera and the most caudal is the skin of vulva or scrotum and perineum. The middle layers of the pelvic floor are made up of predominantly muscular tissue. Apart from the pure pelvic floor muscles, fibromuscular and fibrous elements, such as the endopelvic fascia, are found in this layer. The following muscles together form the muscular layer of the pelvic floor: levator ani, striated urogenital sphincter, external anal sphincter, ischiocavernosus, and bulbospongiosus. All these muscles work together to seal off the lower aspect of the pelvic cavity. The urethra, vagina, and rectum pass through the pelvic floor and are surrounded by the pelvic floor muscles. The pelvic bones are the structures to which the muscular layer is attached.
The function of the pelvic floor is to support the pelvic organs. This occurs through pelvic floor muscle contraction and relaxation. In its resting state the pelvic floor gives support to the pelvic organs. Whether the support function is normal depends on the anatomical position of the muscles, on the activity of the pelvic floor muscles at rest (active support), and on the integrity of the fascia (passive support). When intra-abdominal pressure rises, the pelvic floor muscles must contract to maintain the support function of the pelvic floor. A contraction of the pelvic floor muscles results in a ventral and cranial movement of the perineum and an upward movement of the pelvic organs together with an anterior movement caused primarily by the vaginal and rectal parts of the levator ani. During the pelvic floor muscle contraction, the urethra closes, as do the anus and the vagina. This contraction is important in preventing involuntary loss of urine or rectal contents. For maintaining continence it is also important to realize that bladder activity is inhibited by pelvic floor muscle contraction.
Pelvic floor muscle relaxation following contraction results in a reduction in the support given to the urethra, vagina, and anus. The perineum and the pelvic organs return to their anatomical resting position. The pelvic floor muscles must relax to allow for normal voiding of urine. The same is true for relaxation before and during defecation, when the angle of the anus and rectum become more vertical, allowing for rectal emptying. In the case of dysfunctional voiding, abnormal contraction of the pelvic floor muscles occurs during voiding and may cause closure of the urethra and an intermittent flow or premature cessation of bladder emptying.
ROLE OF LOWER URINARY TRACT (LUT) REHABILITATION
LUT rehabilitation is a nonsurgical, nonpharmacological treatment for LUT dysfunction. LUT rehabilitation, also referred to in the literature as “pelvic floor rehabilitation” or “urotherapy,”1 typically includes pelvic floor training, biofeedback, and behavioral modification.
Pelvic floor training is defined as repetitive, selective, voluntary contraction, and relaxation of specific pelvic floor muscles. This training necessitates muscle awareness to use the correct muscles and to avoid unwanted contractions of adjacent muscle groups.
Biofeedback is a technique used to present visual, auditory, or tactile signals to the patient and therapist about a normally unconscious physiological process. The signal is derived from a measurable physiological parameter, which is subsequently used in an educational process to accomplish a specific therapeutic result. The signal is displayed in a quantitative way and the patient is taught how to alter it and thus control the basic physiological process.
In the case of LUT rehabilitation, biofeedback includes the transmission of pelvic floor muscle activity through surface electromyography (sEMG), which is displayed as a visual image on a computer screen. Behavioral modification comprises analysis and alteration of the relationship between the patient’s symptoms and his/her environment for the treatment of maladaptive voiding patterns. This may be achieved by modification of the behavior and/or environment of the patient.
For more than 2 decades LUT rehabilitation has been practiced by nurses, physiotherapists, midwives, and physicians for the treatment of children in many European and Asian countries.2–5 Similar treatment of children for LUT dysfunction has been utilized only recently in the United States by nurses and physicians but with similar positive results.5–14 Strikingly, there are no studies published in the United States where physical therapists are the primary providers of these interventions with children.
Physical therapists are trained to manage clients with neuromuscular movement dysfunction in a way distinctly different from other health care professionals. Physical therapists have been involved in treating adults for pelvic floor rehabilitation as part of the women’s health initiative for many years. They function in an appropriate environment, with adequate resources, designed to perform hands-on intervention that other health care providers may not have. Physical therapists possess the knowledge and training related to movement dysfunction and rehabilitation techniques, which other health professionals may not possess. Pediatric physical therapists have not typically treated children with incontinence despite their knowledge of children’s musculoskeletal systems, normal development, and age appropriate interventions with regard to neuromuscular re-education and strengthening. It seems logical that after further training in LUT rehabilitation, pediatric physical therapists would be well suited to treat pediatric patients for dysfunctional voiding and urinary incontinence.
Close collaboration must be established between the physical therapist and the referring urologist. This ensures that an appropriate program can be tailored to the patient’s specific voiding dysfunction, diagnosis, and his/her personal needs and circumstances. The urologist’s assessment typically includes physical examination, urinalysis (culture and sensitivity is done if urinalysis is suggestive of infection), bladder ultrasound to assess bladder wall thickness, postvoid residual volume, and constipation. In the presence of infection, a more extensive investigation is required. Uroflowmetry study, combined with electromyography, will be done to determine if there is bladder/sphincter incoordination or if the problem is confined to the bladder (overactive or underactive). Traditionally, the urologist’s first line of treatment addresses bowel management followed by the use of medications such as anticholinergics. When these fail and in the presence of inappropriate pelvic floor activity, α-blocker therapy has been helpful. An example would be extended-release oxybutynin, which has been found effective for the treatment of persistent daytime urinary incontinence.15 These medications are not necessarily curative and have side effects. Their function is to maintain the child until maturation of voiding reflexes occurs, which may take months to years. Medications do have a role and can be used in conjunction with LUT rehabilitation in the more resistant cases.
The primary purpose of this report is to describe the physical therapist’s role in the LUT rehabilitation for a child with daytime urinary incontinence. A secondary purpose is to emphasize that when treating children for voiding dysfunctions, although the approach may be similar to adults, the therapist must be acutely aware of what is appropriate for the evaluation and treatment of children at different ages and varying emotional and cognitive development.
Description of the Case
The patient was an 8-year-old girl who was referred for physical therapy by her urologist with a diagnosis of pelvic floor muscle hypertonus and bladder/sphincter dyscoordination resulting in daytime urinary incontinence (4–8 leaks/d, 7 d/wk).
A thorough history of the current problems was gathered from the caregivers and the physician. The history should include report of surgeries, previous urological test results, continence/voiding history, activity limitations because of incontinence, medications, allergies, other medical problems, pain, social history (including living situation, cognitive, cultural issues), psychosocial environment and achievement of developmental milestones, and treatments for incontinence (pharmacological and nonpharmacological). The patient was asked questions regarding her understanding of the problem as well as her perceived severity of the problem. The therapist asked the patient and her mother what their goals for the outcome of treatment were.
“Primary incontinence” is seen in a child who has never been continent whereas “secondary incontinence” occurs when a child who was previously continent becomes incontinent with a stressor in their life such as a divorce, starting school, moving, etc. In the case presented here, the patient’s mother reported that the patient had developed typical potty training and continence early on and had remained dry until 4 years of age when she began attending preschool. It was at this time that the patient began having episodes of daytime incontinence, which remained constant since that time. This presentation would be considered secondary incontinence. Secondary incontinence often improves on its own as stressors fade; however, in this case, the patient’s mother expressed concerns about her daughter’s continued incontinence at school. She reported that the previous year she was called frequently by school personnel to bring clean/dry clothes as her daughter had wet through the extra set of clothes that were kept for her. In addition, she was concerned because her daughter did not always tell adults when she was wet and spent extended periods of time with wet underwear leading to skin irritation.
The patient was followed by a pediatric urologist who completed uroflowmetry combined with electromyography (Fig. 1A) and referred the patient for physical therapy because of significant dyscoordination between the bladder and pelvic floor. Dyscoordination is defined as increased or steady electromyographic activity of the pelvic floor muscles during voiding in an otherwise neurologically normal individual.
No other surgeries or urological procedures were performed before initiation of physical therapy. The only medication the patient previously was on was for constipation, however, the prescription was finished and had not been refilled by the parent. Other significant items from the history and symptom questionnaire included that the patient sometimes had difficulty initiating the urine stream, that she frequently felt that her bladder was not empty following voiding and needed to return to the toilet to void more (small amounts), that she had to repeat second grade because of time missed which correlated with problems with incontinence, and that the patient felt that the severity of her problem rated a 7/10 with 0 being not severe at all and 10 being the most severe problem imaginable.
Dysfunctional Voiding and Incontinence Symptoms Score Questionnaire (DVISS)
The patient’s mother completed the DVISS questionnaire with the patient’s input (Table 1). The DVISS is a scoring system composed of 13 items regarding daytime symptoms, nighttime symptoms, voiding habits, bowel habits, and a quality of life question.16 Statistical analysis of this tool revealed that within a confidence interval of 96.2% patients with a score of 8.5 or greater had voiding abnormalities, with 90% sensitivity and 90% specificity. The DVISS has been validated to provide an accurate, objective, and scientific basis to grade the symptoms and outcomes of patients with wetting and functional voiding disorders. The patient scored 9 on the initial scoring indicating that she had voiding dysfunction. An additional quality of life question was asked, “If your child experiences the symptoms above, does it affect his/her family, social or school life?” with the available answers being: No, Sometimes, Yes affects, or Seriously affects. The patient and mother replied “sometimes” to the quality of life question.
Bladder Log (also Referred to as a Voiding Diary)
The patient and her mother were asked to complete the bladder log for 1 week. This included voiding frequency and approximate volume, bowel frequency, fluid and fiber intake, wet clothing, nocturnal enuresis, sensation of bladder awareness, daytime incontinence, urge at time of leakage and activity at time of leakage.
Significant findings from the bladder log included that the patient voided between 8 and 10 times/d, indicating that she had increased frequency, which is defined as voiding 8 or more times/d. The patient had urinary incontinence from 4 to 8 times/d and no nocturnal enuresis. The amount of leakage ranged from wetting the underwear to wetting the outer clothing. She drank 5 to 8 (4 oz) glasses of fluids/d, had decreased intake of fiber and 2 to 3 bowel movements/wk of a hard consistency and with straining. The Bristol Stool Form Scale17 is used to describe the stool with type 1 being small hard pebble-like stool and type 7 being watery stool. The patient rated her typical bowel movements as type 2, indicating that she had constipation. Constipation is typically addressed by the physician before LUT rehabilitation due to the fact that increased stool in the rectum can press against the bladder, causing the bladder to be overactive and leading to incontinence.
Screening of the whole body including strength, muscle tone, range of motion, posture including lumbosacral area, gross motor skills, fine motor skills, sensorimotor skills, sensation and pain, revealed these areas were within normal limits.
A perineal examination is typically performed on patients with questionable neurological concerns, to assess skin condition, resting position of the pelvic floor, visual ability to contract/relax pelvic floor muscles, visual response of muscles to a cough, and anal wink. These items were deferred and therefore not visually assessed, nor were they subsequently examined, as the patient was otherwise neurologically within normal limits.
Pelvic Floor Muscle sEMG Responses
Romananzi et al18 has documented procedures for assessing pelvic floor muscle strength using digital evaluation and reported its correlation with sEMG. It is the procedure at our clinic to utilize sEMG to gather general information regarding the patient’s ability to identify, isolate, activate, and coordinate the pelvic floor muscles and not to specify pelvic floor muscle strength measurements. To gather the sEMG information, the patient was sitting in a semireclined position and was disrobed under her gown. She was given instructions on what the procedure would entail. Emphasis was placed on the fact that the procedure would not hurt because the electrodes would be placed on the skin perianally. She was reassured that this procedure would only take place if her mother were present and with her consent. Biofeedback equipment utilized was the Prometheus Synergy 3-D software (Prometheus Group, Dover, New Hampshire) installed on a Dell laptop with the Prometheus MR-20 amplifier attached. Lead wires led from the MR-20 and attached to 3 Easytrode White Cloth Pregelled 1.25 inches × 0.75 inches rectangular snap connector surface electrodes (Prometheus Group). A single channel sEMG was used with 2 electrodes placed perianally over the levator ani muscles. They were placed at 4 and 10 o’clock, on either side of the anus, to prevent the electrodes from touching and causing artifacts. A ground electrode was placed on the greater trochanter. The patient was taught to identify the location of the pelvic floor muscles by acting as if she were trying to keep from passing gas. During this contraction she was coached to try not to move, keeping the rest of her muscles “quiet” and relaxed during this time (similar to Kegel exercises19). The computer monitor reflected the gross activity of the pelvic floor muscles, not specific muscles, as surface electrodes are unable to isolate individual muscle activity. During a voluntary contraction of the pelvic floor muscles, the intensity of the electromyogram (EMG) signal would be expected to increase on the computer screen. When the patient is asked to hold the contraction, a sustained high intensity on the EMG signal was expected to be observed. At the subsequent relaxation the intensity would be expected to fall to, or even below, baseline.
Pelvic floor baseline resting muscle activity was recorded for 60 seconds at which time the patient was instructed to sit quietly and relax. The resulting sEMG signal was noted to be elevated. This indicated that the patient had increased activity of pelvic floor muscles during what should have been a relaxed period of time (Fig. 2A). Pelvic floor muscle activity and coordination were examined in two ways. The first way was to record 10 repetitions of a 10-second contraction followed by 10 seconds of relaxation to examine the slow twitch muscle fiber activity. The second way was to record 10 repetitions of a 2-second contraction followed by 4 seconds of relaxation to examine fast twitch muscle fiber activity. The resulting sEMG demonstrated discrete cycles of pelvic floor muscle contraction and relaxation, which were not smooth or timely (Fig. 3A). This indicated that the patient had decreased coordination. The patient was also observed not to achieve or maintain a relaxed state between contractions.
Activities of Daily Living
No protection (pad, pull-up, etc.) for incontinence was worn. No alarm watches or pagers with alarms were used as reminders to go to the toilet. Although the patient could physically change her own clothes, she would often stay in wet undergarments and not tell adults that they were wet.
During examination with sEMG, the patient demonstrated incoordination of the pelvic floor muscles with an inability to relax. This finding concurred with the physician’s findings during the uroflowmetry where he noted increased electromyographic activity of the patient’s pelvic floor muscles during voiding. This in turn led to incomplete emptying of the patient’s bladder, increased frequency of voiding, and subsequent urinary incontinence. In addition, the patient reported constipation, which is often a result of decreased intake of fluid and fiber and difficulty relaxing the pelvic floor muscles during defecation. Therefore, physical therapy was indicated to improve muscular coordination and relaxation as well as activities of daily living.
Plan of Care
Physical therapy was recommended 1 d/wk for a 1-hour session for 12 weeks to address neuromuscular re-education, therapeutic exercise, therapeutic activity and a home program.
Description of the Intervention
It is important that patients have an age appropriate understanding of what is happening inside their body, including LUT and pelvic floor muscle anatomy and function. In addition, they should agree that they are motivated and committed to make the changes needed to improve their problem. Positive support and encouragement of the mother and the treating physical therapist are also helpful with assisting the patient to reach the desired outcome.
Initial treatment included neuromuscular re-education of pelvic floor muscles including relaxation and coordination through several sets of “roll for control”20 exercises developed by Hulme and performed in conjunction with biofeedback. The biofeedback was set up using perianal surface electrodes with the same set-up as during evaluation. The exercises are completed by contracting the obturator internus, with abduction and external rotation of the lower extremities with heels together. This is followed by contracting the adductor muscles with internal rotation and toes together. The obturator internus and adductor muscle contractions cause lifting of the pelvic floor muscles.21 “Roll for control” exercises seem to be easier for children to do when compared to Kegel’s exercises. This is most likely because the parents can observe the child completing the “roll for control” exercises and the children can experience and feel the lower extremity movement while Kegel exercises produce nonvisible contractions of the pelvic floor. During the treatment session, the patient would be in a semireclined position utilizing biofeedback, which included having the patient watch the computer monitor while completing her “roll for control exercises”. This enabled her to see the contraction and relaxation of the pelvic floor muscles and focus on relaxing her pelvic floor between contractions. Although this provided the patient the ability to produce differences based upon what she saw on the computer that day, specific comparisons of amplitudes from session to session could not be made due to the fact that normalization of amplitude was not performed. The patient completed 6 repetitions of her exercise regime. It included: rolling her knees out against a theraband strap and holding the contraction for 10 seconds (Fig. 4), followed by a 10 second rest and then rolling her knees in against a soft 8-inch ball and holding the contraction for 10 seconds (Fig. 5), followed by a 10 second rest. The patient was given rest periods between sets of exercises. The total number of repetitions was dependent upon her tolerance and muscle fatigue, which were monitored by the physical therapist. During the rest periods the therapist would provide educational information to the patient.
The information included: education on LUT anatomy and function utilizing age appropriate materials such as models, pictures, handouts, and puzzles. In addition, she was taught the importance of consuming the recommended amount of fluid, which was one 8 oz glass of fluid, per year of age, per day. In the case of this 8-year-old patient this would be eight 8 oz glasses of fluid/d. She was also educated about increasing fiber intake by eating at least 13 g of fiber/d. The formula for determining the recommended number of grams of fiber = age + 5 g/d, for the purpose of decreasing constipation and improving continence. The physician recommended that this amount might be doubled if necessary. Homework included increased intake of fluid and fiber to recommended levels, demonstrating increased relaxation of pelvic floor muscles during voiding and completing 3 sets of “roll for control” exercises per day as demonstrated during her therapy session. Completion of the home program was documented by the patient on a home program chart and brought back the next session. The emphasis of the home program chart was on having the patient be in control of her own bladder.
Progression of remaining treatments and home program included progressing the “roll for control” program from a semireclined position, to a sitting position and then to a standing position. The patient was taught fast twitch contractions of the pelvic floor muscles which were a contraction lasting 2 to 3 seconds followed by 4 seconds of muscular relaxation. Fast twitch contractions were taught to the patient to use as a strategy to inhibit bladder contractions to avoid having episodes of incontinence on her way to the toilet to void. Additional repetitions of the fast twitch exercises were also completed with the addition of computerized animation using the same procedure for biofeedback previously described. The animated programs included a dolphin jumping, a shuttle docking, a rose opening and closing or a high jumper jumping (Prometheus Synergy 3-Dimensional Software). This animation was helpful in motivating the patient to complete the required exercises. Behavioral modifications included timed voiding, which was having the patient take the time to void 4 to 5 times/d or approximately every 3 hours. In addition, she was instructed on improving her sitting posture on the toilet during voiding. The posture taught included having the patient keep her thighs spread, feet supported and trunk leaning slightly forward. She was also instructed to perform breathing and blowing exercises for overall relaxation during voiding. She was taught to complete a “double void” which meant that she completed a second void after the first, to try to empty the bladder completely. The patient’s mother signed a release to have the treating physical therapist contact the patient’s classroom teacher to discuss ways that the patient could be better supported in school regarding her incontinence problem. The teacher understood the need for the patient to have bathroom breaks every 3 hours and reported that she could give the whole class bathroom breaks at these intervals to accommodate the patient’s needs without singling her out.
Description of the Outcomes
The patient completed 11, 1-hour, treatment sessions over a 16-week period. Normal levels of voiding frequency (4 to 5 times/d) occurred by the third week of therapy and complete recovery of normal function, including daytime continence, occurred by the eleventh therapy session. By discharge at the eleventh therapy session, sEMG data indicated increased relaxation (Fig. 2B), endurance, and control of pelvic floor muscles (Fig. 3B) resulting in cessation of urinary incontinence. The patient was independent with performing her exercises, completing an appropriate voiding regime (including bladder and bowel) and consuming appropriate fluids and fiber. Scoring on the DVISS was a “1” due to the fact that the patient did not have a bowel movement every day, as she missed a day or two during the week; however, the bowel movements remained a soft consistency. These results represented a “full response.” In response to the quality of life question, the patient replied “no” indicating that the symptoms did not affect her family, social, or school life.
A follow-up uroflowmetry combined with electromyography (Fig. 1B) was completed by the pediatric urologist approximately 1 year after the patient was discharged from physical therapy. The results indicated significantly decreased pelvic floor activity during voiding with increased peak flow and voided volumes of urine noted. In addition, the DVISS was completed by the patient and caregiver, approximately 10 months after discharge from physical therapy, and it was scored a “0.” This indicated that the patient had no symptoms. This result reflected that the patient demonstrated “continued success,” which is defined as no relapse in 6 months after interruption of treatment. The patient is judged to have “complete success” if there is no relapse in 2 years after interruption of treatment.
Incontinence problems in children must be carefully diagnosed and the most prominent etiological causes identified. This can be readily achieved by taking a careful history with an emphasis on time of onset, frequency of incontinence, whether it occurs during the day only or also at night, history of difficulty with bowel movements (preferably assessed by using the Bristol Stool Form Scale), behavioral problems, and family environment.
LUT rehabilitation has been used with adults since Kegel recommended his exercises. Further research, including controlled studies regarding the efficacy of specific interventions (ie, Kegel exercises or “roll for control” exercises) as well as outcomes of these interventions on specific age levels and medical diagnoses, is recommended. Thus far “roll for control” exercises have been a valuable alternative, or addition, to Kegel’s exercises for young children in our care.
Although LUT rehabilitation is labor intensive, it teaches the children a sense of awareness of how to manage their eliminating functions. The “relearning” process has a better chance to be permanent when coordination between the bladder and the pelvic floor has been reestablished. Published results have shown a success rate of 80% to 90% with this approach.2
It is not surprising that when given the choice, parents will often opt for LUT rehabilitation, provided it is available close to home. It is preferable to maintain appropriate medications for the management of constipation throughout the rehabilitation period. Other medications should be stopped for the duration of LUT rehabilitation to better evaluate the effects of rehabilitation treatment. They can be restarted as adjuncts to LUT rehabilitation when deemed to be necessary. The most resistant cases may require other forms of therapy such as sacral neuromodulation, Botox injections, or the implantation of an Interstim device.
Although functional improvements were noted for this patient, a limitation of this case study relates to the EMG graphs and amplitude interpretation. These may represent changes due to intersession differences in technique/placement and not specific meaningful changes across time, as no EMG amplitude normalization process was used in this study.
This case illustrates that daytime incontinence in children is often of a functional nature and when properly documented will respond to physical therapy.
The authors thank Jay Gould, PhD, for his assistance with editing this manuscript as well as the two anonymous reviewers for their review and feedback.
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