How do training experience and geographical origin of a runner affect running biomechanics?

BACKGROUND: Several studies compared African runners with runners from other places with difference ethnicities to identify biomechanical factors that may contribute to their extraordinary running performance. However, most studies only assessed runners at the elite level. Whether the performance difference was a result of nature or nurture remains unclear. RESEARCH QUESTIONS: This case study aimed to assess the effect of geographical origin and the effect of training on running biomechanics. METHODS: We recruited twenty male runners from two regions (Asian and Africa) at two performance levels (elite and recreational), and asked them to run on an instrumented treadmill at 12 km∙h-1. We measured running kinetics and kinematics parameters, and focused on the parameters that have been shown associated with running performance. We used Friedman test to compare the effect of geographical origin and training on running biomechanics. RESULTS: Compared to recreational runners, elite runners applied higher amount of ground reaction force in both vertical and anterior-posterior directions (P <  0.05, Cohen's d = 1.63-2.03), together with a longer aerial time (P =  0.039, Cohen's d = 1.11). On the other hand, African runners expressed higher vertical stiffness than Asian runners (P =  0.027, Cohen's d = 0.98). However, the increased vertical stiffness in African runners did not lead to a higher vertical loading rate (P >  0.555, Cohen's d < 0.3), which could be a result of a lower footstrike angle during landing (P =  0.012, Cohen's d = 1.36). SIGNIFICANCE: For elite runners, the higher amount of ground reaction force might facilitate a longer aerial time, but could also lead to higher amount of mechanical energy loss. African runners expressed higher vertical stiffness and higher step rate, which might lead to a lower CoM vertical displacement, and furthermore reduce mechanical energy loss.

Effect of suburethral prolene mesh for suburethral function and histology in a stress urinary incontinence mouse model.

OBJECTIVES: To create a mouse model pertaining to mesh-elicited suburethral functional and histological changes after vaginal distention, and to examine the possible mechanism behind these complications. METHODS: We divided 48 virgin female C57BL/6 mice into four groups: vaginal distention alone, vaginal distention followed by prolene mesh implantation, vaginal distention followed by sham mesh implantation and untreated control. Each group was divided into two subgroups for conscious cystometrogram, leak-point pressure testing and harvesting of suburethral tissue 4 or 10 days after vaginal distention. The suburethral tissues underwent immunohistochemistry and western blot analysis of nerve growth factor, matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2. Urodynamic results were compared among groups using one way ANOVA, with Tukey's multiple comparisons post-test for pair wise comparisons. RESULTS: Leak-point pressure in the vaginal distention and vaginal distention + sham mesh groups were significantly lower than in the control and vaginal distention + mesh groups at day 4. Leak-point pressure in the vaginal distention + mesh group were significantly higher than in the other three groups at both day 4 and 10. Immunohistochemistry and western blotting showed increased matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2 levels in the vaginal distention + mesh group at day 4 and 10. Furthermore, nerve growth factor expression was increased in the same area and same group at 10 days. CONCLUSIONS: Increased suburethral tissue matrix metalloproteinase and nerve growth factor expression might be related to tissue remodeling after prolene mesh implantation for stress urinary incontinence.

Urgency-free time interval as primary endpoint for evaluating the outcome of a randomized OAB treatment.

INTRODUCTION AND HYPOTHESIS: This study was conducted to determine whether urgency-free interval (UFI) was effective to evaluate the outcome of overactive bladder (OAB) and the correlation of changes between this parameter and urgency episodes. METHODS: A randomized placebo-controlled trial was conducted involving 73 women with OAB. The interventions for a 12-week period included a vaginal electric stimulation and oxybutynin (2.5 mg) or placebo three times per day. Identical preintervention and postintervention assessments included the measurement of UFI and warning time (WT). The King's Health Questionnaire, Spearman's correlation coefficient (SCC), Kruskal-Wallis, Mann-Whitney U, and Wilcoxon-signed rank tests were used for analysis. RESULTS: A positive and significant correlation between the improvements of WT and UFI was noted in the oxybutynin group (p = 0.009). In all groups, none of the SCC revealed significant correlation between the improvement of UFI and urgency episodes (all p >or= 0.145). CONCLUSIONS: The efficacy of UFI in evaluating treatment outcome of OAB was comparable with that of WT in selected modality.

Randomized comparison of tolterodine with vaginal estrogen cream versus tolterodine alone for the treatment of postmenopausal women with overactive bladder syndrome.

AIMS: To investigate whether vaginal estrogen cream combined with tolterodine is more effective than tolterodine alone in the treatment of postmenopausal women with overactive bladder (OAB). MATERIALS AND METHODS: This is an unblinded study without placebo. A preliminary study consisted of tolterodine 2 mg twice per day for 3 months had been conducted for 25 postmenopausal women with OAB. Over a period of 11 months, 80 postmenopausal women with OAB underwent a prospective randomized trial. These patients were equally randomized into two groups. The interventions for the 12-week treatment period included 2 mg tolterodine twice per day for the group A and 2 mg tolterodine twice per day/vaginal conjugated equine estrogen 0.625 mg twice a week for the group B. Identical pre- and post-treatment assessments included bladder diary, Urogenital Distress Inventory-6 (UDI-6), and Incontinence Impact Questionnaire-7 (IIQ-7). RESULTS: All 80 women (65.2 years, range 58-73) completed this study. The between groups comparison showed that the group B had significant improvements in mean daytime frequency and voided volume after treatment (14.8-5.8 vs. 14.1-6.4, P = 0.001 and 115.8-141.9 vs. 108.5-134.5, P = 0.007, respectively). Additionally, a comparison of the final total scores of UDI-6 and IIQ-7 between the two groups revealed that the group B had a statistically significant improvement in quality of life than that in the group A (8.6-6.9 vs. 9.5-7.2, P < 0.001 and 9.4-6.1 vs. 10.2-6.5, P < 0.001, respectively). Changes in the other symptoms, including nocturia, urgency and urge incontinence, were not statistically significant but actually achieved improved in both groups. CONCLUSIONS: A combination of vaginal estrogen cream and tolterodine is a potential therapy for postmenopausal women with OAB.

A microbiological and immunohistochemical analysis of periurethral and vaginal tissue in women with de novo urge symptoms after mid-urethral sling procedures--a prospective case-controlled study.

The aims were to determine whether bacteria-infection-elicited immune response after mid-urethral sling (MUS) may cause de novo urge symptoms (DNUS) and to evaluate the efficacy of suburethral sling excision for relieving the urgency. In a period of 40 months, 360 consecutive subjects with urodynamic stress incontinence had undergone one of three different MUS. Sixty-eight women with DNUS were included after exclusion. The suburethral sling of 24 of the 68 women needed to be excised because of refractory urgency. The excised vagina, or periurethral tissue, included sling of the study and control groups were sent for microbiological and immunohistochemical analyses. Statistically significant differences in the cell density percentage of CD68, CD25, CD4+CD25 and positive rate of Gram (+) bacteria were noted between two groups (p=0.024, p=0.053 and 0.016, respectively, p<0.001). The success rate of sling excision was 80.2%. In conclusion, bacteria-infection-related immune hyperreactivity might explain the pathologic basis of DNUS after MUS.

Factors affecting voiding function in urogynecology patients.

OBJECTIVE: Our objective was to assess the impacts of menopause, age and parity on voiding function in urogynecology patients. MATERIALS AND METHODS: The medical records of 4,470 patients with urodynamic studies were reviewed at our center between January 1999 and May 2003. Patients with conditions including a prior continence procedure, advanced pelvic prolapse, hysterectomy or neurologic deficits were excluded from our study. Comprehensive medical histories, physical examinations, bladder diaries and results of multi-channel urodynamic testing were analyzed. RESULTS: The mean age of the 3,161 women enrolled was 50 years, and the mean parity was three. Four urodynamic variables served as voiding parameters: maximum flow rate (Qmax) and post-void residual (PVR) from uroflowmetry, and maximum flow rate (Qmax.p) and detrusor pressure at maximum flow (PdetQmax) from pressure-flow studies. Of the three factors studied (menopause, age, and parity), only parity had a significant impact on uroflowmetry and pressure-flow study results (Qmax, p=0.007; PVR, p<0.001; Qmax.p, p=0.002; PdetQmax, p<0.001). Twenty-five percent of the patients in our study were diagnosed with voiding dysfunction. CONCLUSION: Our results indicated that parity had a significant impact on voiding function in urogynecology patients. Twenty-five percent of patients in our study were diagnosed with voiding dysfunction. The bladder behavior in women after childbirth may be more complex than previously thought, and special attention should be paid to women who suffer from bladder symptoms after childbirth.

Comparison of electric stimulation and oxybutynin chloride in management of overactive bladder with special reference to urinary urgency: a randomized placebo-controlled trial.

OBJECTIVES: To compare the efficacy of electric stimulation (ES), oxybutynin, and placebo in managing the symptom complex of overactive bladder (OAB), particularly urgency. METHODS: A randomized placebo-controlled trial was conducted for 68 patients with OAB, placing emphasis on urinary urgency. The interventions for the 12-week treatment period, conducted by the physiotherapist, who was unaware of the progress and outcome, included a vaginal ES program using biphasic symmetric, pulsed current with a 10-Hz frequency, 400-micros pulse width, 10/5 duty cycle, and varying intensity; and oxybutynin (2.5 mg) or placebo three times per day. Identical preintervention and postintervention assessments included the measurement of warning time, urodynamics, voiding diaries, and King's Health Questionnaire. RESULTS: Of the 68 women who completed this study, 24 were in the ES, 23 in the oxybutynin, and 21 in the placebo group. The between-group comparison showed that significant improvements in daily voided volume, pad count, number of urgency and nocturia episodes, and the domain 2 score and total score of the King's Health Questionnaire existed between the ES and the other groups (all P < or = 0.050). The changes in warning time, maximal voided volume, number of urgency episodes, and frequency were significantly improved between oxybutynin and placebo (all P < 0.013). Additionally, a comparison of the voided volume in uroflowmetry between the ES and placebo groups revealed a greater difference after treatment (P = 0.013). The reduction rate of OAB was 58.4% for the ES, 39.1% for the oxybutynin, and 9.5% for the placebo group (P = 0.036). CONCLUSIONS: ES had the greatest subjective outcome for OAB and was the most effective of the three treatments. Oxybutynin was more effective than placebo.

Treatment for unsuccessful tension-free vaginal tape operation by shortening pre-implanted tape.

PURPOSE: We studied the efficacy of shortening the pre-implanted suburethral tape in patients with recurrent urodynamic stress incontinence after a TVT operation. MATERIALS AND METHODS: A total of 14 women, including 6 with ISD, were treated for recurrent urodynamic stress incontinence after the initial TVT operation by performing the shortening procedure under local anesthesia. Urodynamics, a 1-hour pad test, introital ultrasonography of the urethra and a cotton swab test were done before the procedure and 1 year postoperatively. RESULTS: All 14 patients completed the shortening procedure. Mean patient age was 47.2 years (range 43 to 66). Mean time between initial TVT and the shortening procedure was 4 months (range 3 to 14). Ten patients (71.4%) were objectively cured and treatment failed in 4 (2 with ISD and 2 with a fixed urethra). Mean operative time was 17 minutes (range 10 to 25). No intraoperative surgical complications were observed. The 1-hour pad test showed a decrease from a median of 9.0 gm to 1.0. Median postoperative hospital stay was 1 day (range 1 to 4). Spontaneous voiding with adequate post-void residual urine was noted in all patients before discharge home. CONCLUSIONS: Shortening a pre-implanted TVT tape for the treatment of recurrent urodynamic stress incontinence is a safe, effective and minimally invasive option requiring only a short hospital stay. However, ISD and an immobile urethra seem to be risk factors for failure. Long-term followup is needed to determine if this surgery achieves long-lasting results.

Prospective randomized comparison of transobturator suburethral sling (Monarc) vs suprapubic arc (Sparc) sling procedures for female urodynamic stress incontinence.

The aims of this trial were to compare the attendant complications and postoperative voiding function of the Monarc and suprapubic arc (Sparc) suburethral sling procedures. This is the first article in English literature to compare different suburethral sling procedures using prosthesis of the same material and the same weave. Sixty women with urodynamic stress incontinence alone or combined with pelvic prolapse less than International Continence Society stage II were randomly allocated to either the Monarc or Sparc group. A comparison of the peri- and postoperative results comprising complications and symptoms of voiding function revealed no significant differences between the two groups in a follow-up ranged from 6 to 14 months (median, 9 months). However, the nonsignificant increase in tendency of inadvertent vaginal perforation and disability/pain of thigh (Monarc 12.9 vs Sparc 0.0%, p=0.112 and Monarc 12.9 vs Sparc 0.0%, p=0.112, respectively) has clinical significance. Based on the analyses of the comparison of Blaivas obstruction nomograms, postoperative voiding function was not significantly different between the two surgical groups. We concluded that Monarc and Sparc suburethral taping proved to be equally safe and posed no remarkable impact on voiding function in a short term postoperative follow up. However, intraoperative urethrocystoscopy is recommended for safety in both the Monarc and Sparc procedures.

The prevalence of urinary incontinence and associated risk factors in Taiwanese women with lower urinary tract symptoms.

BACKGROUND: To analyze the urodynamic-defined prevalence of urinary incontinence and the associated risk factors in Taiwanese women with lower urinary tract symptoms (LUTS). METHODS: We reviewed the medical records of 4,470 women who were referred to our urodynamic center between January 1999 and May 2003. Their records including a comprehensive medical history, physical examination, bladder diary and results of multi-channel urodynamic testing were analyzed. RESULTS: 3,161 of 4,470 women recruited were eligible for the analyses. The distribution of urodynamic prevalence in 3,161 women revealed that urodynamic stress incontinence (USI) was 1,755/3,161 (55.5%), detrusor overactivity (DO) 231/3,161 (7.3%), mixed incontinence (MI) 142/3,161 (4.5%), voiding dysfunction (VD) 793/3,161 (25.1%) and normal result (N) 240/3,161 (7.6%). The highest prevalence of USI was observed in women aged 40-49 (40.3%) and the prevalence of DO and MI seemed to be lower as compared with the literature reports. Linear regression analysis showed parity (p < 0.001) and three urodynamic study (UDS) variables [maximum free flow rate (p = 0.003), maximum urethral closure pressure (p = 0.003) and functional profile length (p = 0.014)] were significantly related to the urinary incontinence in women with LUTS. Menopause (p = 0.865) had no impact on the urinary incontinence. CONCLUSION: Risk factors contributing to Taiwanese women with LUTS to develop urinary incontinence included multiparity and three specific parameters observed during UDS. Of interest, our data also indicated 25% of patients were diagnosed as voiding dysfunction deserved future study.

Randomized comparison of the suprapubic arc sling procedure vs tension-free vaginal taping for stress incontinent women.

The purpose of this study was to compare the surgical outcome and attendant complications of the suprapubic arc (SPARC) sling and tension-free vaginal tape (TVT) procedures. Sixty-two women with genuine stress incontinence (GSI) alone or combined with pelvic prolapse less than International Continence Society (ICS) stage II were randomly allocated to either SPARC or TVT groups. A routine suprapubic ultrasonography was performed for all patients 1 day after the anti-incontinence operation. A comparison of the peri- and postoperative results comprising surgical outcomes and complications revealed no significant differences between the two groups. Although the difference in the rates of bladder injury was not statistically significant (SPARC 12.9 vs TVT 0.0%, p = 0.112), it was clinically significant. Routine suprapubic ultrasonography revealed eight subjects had retropubic hematomas greater than 5 cm. The cure rate for SPARC was not significantly different from TVT (80.7 vs 87.1%, p = 0.706). We concluded that the SPARC sling and TVT procedures proved to be equally effective. Subsequent suprapubic ultrasonography, in particular for the symptomatic patients, was found to be of clinical merit.

A histologic and immunohistochemical analysis of defective vaginal healing after continence taping procedures: a prospective case-controlled pilot study.

OBJECTIVE: The purpose of this study was to investigate vaginal rejection of polypropylene mesh after continence taping procedures. STUDY DESIGN: Of 700 women who had undergone the procedures, 17 women with sling erosion and 7 women with voiding difficulty or symptomatic vagina prolapse (control subjects) underwent histopathologic evaluation and immunohistochemistry. RESULTS: Seven women whose condition was not responding to conservative treatment and debridements had the exposed suburethral tape excised, which revealed predominant foreign body reaction and fragmented mesh that was surrounded by histiocytes and dense fibrosis. Immunohistochemical analysis revealed that the cell density percentage of CD 20+ cells was statistically significantly greater in the persistent defective healing group than in either the single-debridement or control group ( P = .014 and P = .014, respectively). We found statistically significant differences between the persistent defective healing and single-debridement groups and between the former and control groups in the ratios of T and B cells ( P = .035 and P = .022, respectively). CONCLUSION: The rate of defective vaginal healing after the procedures was 2.4%. Removal of the prosthesis and surrounding tissue at various times for the 7 women resulted in histopathologic findings that suggested a immunologic reaction. The rate of persistent defective healing of the vagina was 1%.

The techniques of trocar insertion and intraoperative urethrocystoscopy in tension-free vaginal taping: an experience of 600 cases.

BACKGROUND: To determine the frequency of lower urinary tract (LUT) injury for stress incontinent women undergoing the tension-free vaginal tape (TVT) procedure with or without concomitant procedures. METHODS: Over a period of 5 years, 600 women who had stress urinary incontinence (SUI), with or without pelvic prolapse, consecutively underwent the TVT procedure either with or without concomitant surgery. All study subjects underwent intraoperative transurethral urethrocystoscopy. During the examination 34 (6%) women at high risk of ureteral injury also received intravenous injection of 6 mL of diluted methylene blue to observe the patency and function of the ureter as well as the integrity of the bladder. RESULTS: The mean patient age was 52.75 years (range 32-76) and mean parity was 2.54 (range 0-6). Of the 600 women, 188 (31.4%) had had previous surgery, 169 (28.2%) had concomitant surgery, and 9 (1.5%) had abnormal urethrocystoscopic findings. These findings included one case each of previously placed suspension sutures, granuloma-like tissue in the bladder, a delayed dye emission from the ureteric orifice, an adhesive band in the urethra, three cases of perforation of the bladder by the trocar and two cases of an area of thin bladder mucosa. The bladder perforation rate related to the TVT device was 0.8% (5/600). CONCLUSIONS: Based on the data of this 5-year review, and a high rate of bladder injury (0-25%) reported in the literature, intraoperative urethrocystoscopy is imperative in the TVT procedure, although the rate of bladder injury was only 0.8% in the present study.

Single-blind, randomized trial of pelvic floor muscle training, biofeedback-assisted pelvic floor muscle training, and electrical stimulation in the management of overactive bladder.

OBJECTIVES: To compare the efficacy of pelvic floor muscle training (PFMT), biofeedback-assisted PFMT (BAPFMT), and electrical stimulation (ES) in the management of overactive bladder (OAB). METHODS: The interventions for the 12-week treatment period, conducted by the physiotherapist who was unaware of the progress and outcome, included (a) a PFMT program tailored to the subject's PERFECT (power, endurance, repetitions, and fast [1-second] contractions, with every contraction timed) scheme, used for training at home; (b) an electromyography BAPFMT program and home program tailored to the subject's PERFECT scheme; and (c) an ES program using biphasic symmetric probe current with 10-Hz frequency, 400-micros pulse width, 10/5 duty cycle, and varying intensity. Identical preintervention and postintervention assessment included King's Health Questionnaire, as well as outcomes of urge incontinence and other urinary symptoms. RESULTS: Of the 103 women who completed this study, 34 were in the PFMT group, 34 in the BAPFMT group, and 35 in the ES group. The changes in the three parameters of King's Health Questionnaire revealed statistically significant differences, except for the total score, between ES and BAPFMT (domain 7, P = 0.003; domain 9, P = 0.029; and total score, P = 0.952). These same parameters were significantly different between ES and PFMT (domain 7, P = 0.007; domain 9, P = 0.001; and total score P = 0.004). The change in total score was significantly different between BAPFMT and PFMT (P = 0.003). The subjective improvement/cure rate of OAB was 51.4% for ES, 50.0% for BAPFMT, and 38.2% for PFMT (P = 0.567). CONCLUSIONS: ES had the greatest subjective reduction rate of OAB and was the most effective of the three treatments. BAPFMT was more effective than PFMT.

Bladder perforation presenting as vulvar edema after the tension-free vaginal tape procedure. A case report.

BACKGROUND: Bladder perforation during the tension-free vaginal tape (TVT) procedure is a common complication. CASE: Vulvar edema was noted 4 hours after application of TVT, and cystoscopy revealed bladder perforation. The patient had a history of a previous vaginal hysterectomy with anterior colporrhaphy. CONCLUSION: To our knowledge, this is the first case report of vulvar edema following TVT. Bladder filling to 250 mL, 70 degrees cystoscopy, good skills in cystoscopy and familiarity with retropubic anatomy are key issues for the TVT procedure. A cystoscopic examination before the TVT procedure should be considered for patients with previous pelvic surgery.

Comparison of tension-free vaginal taping versus modified Burch colposuspension on urethral obstruction: a randomized controlled trial.

AIMS: To determine whether the tension-free vaginal tape (TVT) procedure affects the mechanics of voiding in women with genuine stress incontinence (GSI). METHODS: Between July of 1997 and July of 1999, 116 women with GSI in the absence of pelvic prolapse underwent a randomized controlled study of TVT vs. modified Burch colposuspension. The trial was conducted by using a standardized protocol, including strict criteria for excluding preexisting bladder outlet obstruction (BOO). Urodynamic studies including free flowmetry, filling (provocative) and voiding cystometry, and 1-hour pad test were performed before and at least 1 year after the operation. The Blaivas and Groutz nomogram was used as another criteria to assess the pre- and postoperative BOO. RESULTS: Eighteen women were excluded from the study as a result of having preexisting BOO and an additional 8 were lost to follow-up. The comparison between pre- and postoperative variables for each procedure revealed that maximal flow rate of noninvasive uroflowmetry was significantly lower after operation in both groups (P = 0.009, P = 0.010, respectively). Detrusor pressure at maximal flow and urethral resistance were significantly higher and micturition volumes significantly lower after operation in the Burch group (P < 0.001, P < 0.001, P = 0.029, respectively). The difference between pre- and postoperative distribution of the obstruction nomogram of the Burch group was significantly different (P = 0.023). CONCLUSIONS: Based on strict exclusion criteria for preoperative BOO, our findings strongly suggest that with a median 22 months (range, 12 to 36 months) of follow-up, a properly performed tension-free vaginal tape procedure does not cause urethral obstruction.

A comparison of urethral pressure profilometry using microtip and double-lumen perfusion catheters in women with genuine stress incontinence.

OBJECTIVE: To compare urethral pressure profilometry measurements using microtip transducer and double-lumen perfusion catheters. DESIGN: Prospective study. SETTING: Tertiary referral urogynaecology unit. SAMPLE: Three hundred and ninety two non-pregnant women with various lower urinary tract symptoms. METHODS: Multichannel urodynamic investigations were performed using double-lumen perfusion catheters with external pressure transducers in 392 women. For those 301 (76.8%) diagnosed as having genuine stress incontinence, an investigation with microtip transducers followed. For data analysis, a mixed-effects model was used to evaluate changes in the urethral profilometry and an approach proposed by Bland and Altman was applied to access agreement between the two techniques. RESULTS: Of the 301 women with genuine stress incontinence, 272 were eligible for this study. In resting status, the differences between the two techniques were statistically significant (48.9cm H2O vs 73.4cm H2O, P = 0.0001) after adjusting for age. Moreover, the agreement study also confirmed that these two techniques do not agree sufficiently. CONCLUSION: Maximum urethral closure pressure obtained from the double-lumen catheter was significantly higher than that obtained from the microtip catheter. Use of the double-lumen catheter for the measurement of maximum urethral closure pressure can be considered a reliable technique since its reproducibility is as good as that of the microtip catheter. Therefore, the diagnosis of 'low pressure urethra' will be different between the two techniques.