Braekken IH, Majida M, Engh ME, Bo, K: Morphological Changes after Pelvic Floor Muscle Training Measured by 3-Dimensional Ultrasonography. Obstet and Gynec. 2010; 115(2):317-24.

Pelvic Physiotherapy Think Tank

July 6, 2011

Ann Dunbar PT, DPT, MS

Objective: To investigate morphological and functional changes after pelvic floor muscle (PFM) training in women with pelvic organ prolapse (POP). 

Introduction:

1.       Authors report RCT and systematic reviews exist to demonstrate that PFM training effective in rx SUI for 44-80% adult females but few data exist to suggest PFM training also effective to reduce sx of POP.

2.       Suggest 2 hypotheses explaining mechanism of action of PFM training for rx of SUI/POP. (1) Teaching women to contract PFM before and during increased intra-abdom pressure; (2) Strength training of PFM builds m volume, elevates organs and closes levator hiatus

Study Aim

To use 3 and 4 dimensional ultrasonography to assess possible change in: (1) morphology, such as size of levator hiatus, pubovisceral m thickness and length  ; (2) function measured as the size of hiatus,  position of the rectum and  bladder and  pubovisceral m. length during maximum Valsalva after 6 months of PFM training (PFMT)

Materials and Methods

1.  Study Design:  assessor blinded RCT.  Effect size of 0.6 determined w/ previous

     research (1999); Power=80%. Sample size 45 but chose to include 50 because of

      potential drop outs.

3.    Subjects: Women at least 1 yr pp in Norway with POP stages I, II, III determined by

        POP-Q

4.  PTs did assessment of PFM function (ability to contract, strength, endurance, and

      vaginal resting pressure) using : responsive, reliable, and valid vaginal squeeze

      pressure transducer (manufacturer listed).

5.   GYN did POP-Q at hospital w/ table at 30 degree angle

6.  Women divided into 2 groups by severity of prolapse and were randomly assigned

       to either PFMT group or control group  

7.   Instructions to subjects:

a.      Women in both groups advised to avoid straining and were observed and taught by PT how to contract PFM before and during increases in abdominal pressure.

b.      Women in control group asked not to change frequency or start PFM training during intervention period

c.       PFMT protocol: PT supervised individual strength training 1x/wk for first 3 months and then once every 2 wks for next 3 months. Session included 3 sets of 8—12 maximal contractions in lying, sitting, standing; First set was supine w/ use of vaginal squeeze pressure transducer to monitor vaginal squeeze pressure. Did home exercises the entire 6 mo study period: Protocol included 8—12 close to maximal contractions per day. Women recorded home training adherence in diary; PT recorded office visits. Adequate exercise adherence defined as 80% (144+ days of ex and 14+ office visits). All women in PFMT group also received booklet and DVD showing ex program

2.       Participant GYN examination:

a.      3D volumes recorded in resting in lithotomy. 4D recordings taken in standing doing PFM contraction w/ legs in slight abduction (X3) and in lithotomy doing Valsalva maneuvers (X3)

3.      Measurement technique:

a.  Described plane of minimal hiatal dimension in lithotomy

b. Describes measurement of thickness of  pubovisceral m (PVM), levator

      hiatus, PVM length, position of bladder and rectum at rest in standing (all

      methods list statistics from previous research)

9.  Statistical analyses

                a. Results given as means with SD or 95% confidence intervals. Data checked

                   for normality; Within and between-group comparisons were tested;

                   Differences between groups in baseline categorical data analyzed. Effect

                   size calculated. Relationship between increase in PFM strength and

                   morphological changes analyzed. No interim analyses. P<0.05 considered

                   significant

Results

1. N=145 women with POP recruited; flow chart provided with reasons for exclusion

     and drop out

2. Random allocation for 109 women to PFMT (n=59) or Control (n=50); 47 (79%

     reached 80% adherence level

                a. “Postal questionnaire” sent out 6 mo after initial testing

                b. Five in control group acknowledged increasing PFMT frequency

4. At baseline, no statistical difference between groups for m. thickness, hiatal area

     at rest, hiatal area with Valsalva, position of bladder and position of rectum

 5. Women in PFMT group had increased PFM strength 13.1 cm H2o (95% CI 10.6---15.5)

      compared to 1.1 cm H20 (95% CI 0.4—2.7) p<.01

6. Positive correlation between increased PFM strength and the following variables:

     increased m. thickness, decreased hiatal area and maximum Valsalva, shortened m.

     length at Valsalva, elevated bladder and elevated rectum. No correlation between

      increased PFM strength and change in size of levator hiatus and m. length at rest

See Table 3 for summary of morphological and functional changes of PVM after PFMT

Discussion

1. RCT supports findings of other uncontrolled studies that showed increased m. thickness, decreased levator ani m. surface and elevated resting position of bladder

2.  Results demonstrate that though PFM contraction in advance of increased intra-abdominal pressure does reduce stress urinary incontinence (SUI), it does not increase PFM strength

3.  44% increase in m. strength; 15% increase in m. thickness

4. This study also demonstrated functional changes: Resting position of bladder and rectum elevated; PVM length and hiatus size at maximum Valsalva decreased

5.  This study demonstrated a decrease in levator hiatus area by 1.5 cm² after PFMT

6. Strengths of study:  because of the population selected for study, results are

    generalizable across populations of asymptomatic women and those with

    SUI but not to women with more severe POP

7. Authors note study’s intervention is rigorous and suggest future study to see if

     same results attainable with less rigor (eg PFMT in groups instead of individually or

     decrease number of visits)

PEDro score for this study 8/10

Thought Questions

1. How do these findings fit into your understanding of the optimal PFM exercise prescription?

2. Do you agree with the PFMT intervention?

3. Is reducing the size of the levator hiatus important?

4. Do you think there is anything else involved that might have affected the outcomes?

Much discussion followed.  Listed to recording for details.

Other articles referenced during the discussion.

Braekken IH, Majida M, Engh ME, Bø K Can pelvic floor muscle training reverse pelvic organ prolapse and reduce prolapse symptoms? An assessor-blinded, randomized, controlled trial.  Am J Obstet Gynecol. 2010 Aug;203(2):170.e1-7. Epub 2010 May 1.

Choi H, Palmer MH, Park J.  Meta-analysis of pelvic floor training: randomized controlled trials in incontinent women.  Nursing Research. 2007; 56: 226-234.