Load Transfer Failure – Treatment Of Factors Influencing The Pelvic Floor

Countless times while talking to patients, women have disclosed to me that they have tried “Kegels” in the past with absolutely no change in symptoms, or an improvement that has not eliminated their pelvic concerns. As such, these women tend to be skeptical of pelvic floor physiotherapy and the ability of a therapist to eliminate or improve their symptoms. These women often times suffer from various pelvic floor prolapses or issues of incontinence despite having done “Kegels” for years.

 

Although each person is unique, upon further testing, many of these individuals share similar postural and load transfer patterns all resulting in one unified result – load transfer failure.

 

As the pelvic floor is an integral part of our orthopaedic system, we must ensure we are carefully assessing the pelvic floor in addition to the other orthopaedic elements that can contribute to pelvic floor dysfunction.

 

When looking at muscles that can affect pelvic floor function we must explore global (rectus abdominus, external oblique) versus segmental (transversus abdominus, pelvic floor) muscles. Various EMG studies have determined that global versus segmental muscles behave differently during functional activities. Global muscles produce phasic activation, while segmental muscles are tonic, producing a low level contraction constantly through movement. When individuals have an imbalance in recruitment of these muscles it can lead to resultant failure of load transfer during functional activities.

 

Hodges et al in 2007 identified that with arm elevation, the pelvic floor remained constantly active throughout motion. Therefore a decrease in the ability to contract properly through the pelvic floor can have a profound impact on the ability to perform simple functional tasks as lifting the arm affecting lifting and carrying tasks. Thus, compensations begin to develop with a dominance of global muscle systems.

 

As we explore the interplay between “the Core” (pelvic floor, transversus abdominus, diaphragm, and multifidus), it is imperative that we identify postural dysfunctions that can lead to load transfer failure. Chronic postural compensations can result in under-activity of core muscles groups, often paired with over activity of superficial global muscles.

 

In individuals with load transfer failure, particularly those with reports of stress urinary incontinence and pelvic organ prolapse, we can begin to see postural patterns develop. We often see a loss of lordosis in the lumbar spine or posterior pelvic tilt paired with an increase in a thoracic kyphosis, both in resting and functional positions. These postural compensatory positions can have a gross impact on the ability of the transversus abdominus (TvA) to contract effectively.

 

As a result of the connection of the TvA to the pelvic floor via the intervening fascia, it is therefore of utmost importance that pelvic positioning is explored in each patient.

 

A study by Sapsford et al (2001) summarized that the ability to contract through the deep transversus abdominus was directly proportional to the position of the pelvis. The most optimal recruitment of TvA occurring with a neutral pelvis (slight lumbar lordosis). The same EMG study concluded that when attempting to contract TvA with a posterior pelvic tilt, there was far less contribution from TvA and over-activity of the external oblique musculature. This is an adaptive position of many individuals with SUI/prolapse. This posture creates a flexion position through the anterior thorax, creating increased activity through the external obliques.

 

So what you might ask?

 

When this patterning of external oblique dominance occurs, intra-abdominal pressures increase creating increased pressure on the pelvic floor musculature. This muscle functioning can be viewed to act as a trash compactor, forcing load and pressure downward on the pelvic floor. This ultimately causes a greater demand on the pelvic floor, with an inability to counter these pressures resulting in muscular fatigue followed by load transfer failure.

 

Therefore to optimize one’s ability to perform a proper pelvic floor/transversus abdominus contraction, we need to ensure we are promoting optimal pelvic positioning for core recruitment and down regulating over activity from superficial muscles, most notably the external obliques.

 

However, we cannot only look at pelvic mobility in isolation. We also must explore the intervening factors of why perhaps a posterior pelvic tilt is a dominant positioning pattern. We typically see a posterior pelvic tilt paired with an increased thoracic kyphosis further contributing to over-activity of the external oblique and rectus abdominus groups, and limiting mobility of the diaphragm. Therefore our treatment must be focused on all of these postural elements to first correct form to enhance recruitment through the core muscular groups.

 

To create a lasting effect it is imperative that we integrate these changes into static positions followed by functional movement patterns to effect motor control, learning, and retention.

 

Training the pelvic floor is simply not enough. We must re-educate people on how to move with efficiency and promote strength and alignment through all facets affecting the pelvic floor.

 

Written by:

Michelle Vanderpol
Lab Assistant

 

References:

 

Claus, A., Hides, J., Moseley, G., & Hodges, P. “Different ways to balance the spine: subtle changes in sagittal spinal curves affect regional muscle activity”. Spine.34.6 (2009): E208-14.

 

Hodges, P., Sapsford, R., & Pengel, L. “Postural and respiratory functions of the pelvic floor muscles”. Neurourol Urodyn. 26.3 (2007): 362-71.

 

Sapsford, R., Hodges, P., Richardson, C., Cooper, D., Markwell, S., & Jull, G. “Co-Activation of the abdominal and pelvic floor muscles during voluntary exercises”. Neurourol Urodyn 20.1 (2001):31-42

 

Sapsford, R., Richardson, C., Maher, C., & Hodges, P. “Pelvic floor muscle activity in different sitting postures in continent and incontinent women”. Arch Phys Med Rahbil. 89.9 (2008): 1741-7.

 

Smith, M., Coppieters, M., & Hodges, P. “Postural activity of the pelvic floor muscles is delayed during rapid arm movements in women with stress urinary incontinence”. Int Urogynecol J Pelvic Floor Dysfunct. 18.8 (2007): 901-11.

 

Urguhart, D., Hodges, P., Allen, T., & Story, I. “Abdominal muscle recruitment during a range of voluntary exercises”. Manual therapy. 10.2 (2005): 144-53

 

Urguhart, D., Hodges, P., & Story, I. “Postural activity of the abdominal muscles varies between regions of these muscles and between body positions”. Gait Posture. 22.4 (2005): 295-301.