Gait changes on a treadmill

Something to ponder on those days when getting outside it just impossible because of weather.
Athletes might respond to fatigue differently when running on a treadmill compared with overground conditions, where pace is typically more variable.
“Before halfway, step length increased and cadence decreased, whereas during the latter stages, there were significant decreases in impulse and maximum force. Contact time decreased and flight time increased continually, but otherwise most gait variables did not change. The changes in contact and flight times suggested that athletes altered their gait so that more time was spent airborne to allow the treadmill to pass under them. In general, however, the runners maintained their techniques throughout the run. ”

Human Gait Changes following mastectomy. Taking Angelina Jolie’s news and putting it into gait context.

The Gait Guys are on the case looking at the effects of gait changes following mastectomy just a day after the news of Angelina Jolie’s double mastectomy.

Research has confirmed that following a mastectomy there are limitations in the efficiency of the upper limb and even changes in the posture of the torso. (1,2,3)

Following mastectomy, whether unilateral or bilateral, restorative measures are necessary. From a biomechanical perspective, obviously depending on breast size, removing a considerable mass of tissue is going to change the symmetry of the torso particularly if we are dealing with a unilateral mastectomy.  Not only is it going to change symmetry from a static postural perspective but it will change dynamic postural control, mobility and stability as well as dynamic spinal kinematics.  The literature has even shown that post-mastectomy clients display changes in spatiotemporal gait parameter such as step length and gait velocity.

Breast tissue moves. It oscillates a various cycles depending on speed of walking or running.  There is a rhythmic cycle that eventually sets up during walking and running and the cycle is intimately and ultimately tied to arm swing.  Thus, it would make sense that removing a sizable mass of tissue, particularly when done unilaterally, will change the tissue and joint rhythmicity. And if you have been here with The Gait Guys for more than a year you will know that impairing an arm swing will show altered biomechanics in the opposite lower limb (and furthermore, if you alter one lower limb, you begin a process of altering the biomechanical function and rhythmicity of the opposite leg as well.)  Here are 2 links for more on these topics, Arm Swing: Part 1 and Arm Swing: Part 2, When Phase is Lost. Plus here from our blog search archives, everything we have talked about on Arm Swing.

Arm swing impairment is a real issue and it is one that is typically far overlooked and misrepresented. We are currently working on several other blog posts for near future release including walking with a handbag/briefcase, walking with a shoulder bag, walking and running with an ipod or water bottle in one hand and even spinal symmetry changes from scoliosis that can either consciously or unconsciously alter arm swing and thus global body kinematics.  (We have also noted changes in opposite leg function secondary to a frozen shoulder (adhesive capsulitis) and we have that blog article in the works as well.)  The bottom line is that because of the neurologically embedded crossed extensor reflex and cross crawl response that permeates all human locomotion, anything that changes one of the limbs, whether it be a direct limb issue or something to do with the stabilization of the limb (as in this case the breast/chest wall), can and very likely will impair and change locomotion and motor pattern choices and programming.

Obviously the degree to which intervention is taken depends on the amount and location of breast tissue removed and intervention will be determined by physical placement of the prosthesis (whether it be external or internal) as well as the prosthesis weight, shape and possibly several other independent factors such as comparative support to the chest wall in comparison to the opposite breast. (In another future blog post we will address other methods of intervention such as latissimus dorsi relocation to reform the breast mass. This deserves a blog article all on its own because taking away a major shoulder, scapular and spinal stabilizer and prime mover has never made sense to us clinically or biomechanically.)

In Hojan’s study (below) they found significant differences in the gait parameters in the younger age groups with and without breast prosthesis however there appeared to be no significant differences in the women of the older study group.  However, it appeared that their study did not take into account all of the intimate issues we talk about in gait here on The Gait Guys blog. None the less, in the younger and likely more active study group, the use of a breast prosthesis brought the gait parameters closer to the healthy control group, as we suspected. 

Bottom line, every external and internal parameter that changes affects the human organism and thus affects their gait.

Again, here are those links to our other blog writings on arm swing that are paramount to understanding what we are discussing here today.

Arm Swing Part 1: The Basics

Arm Swing Part 2: When Phase is Lost

From our blog search

Shawn and Ivo, The Gait Guys

1.Blomqvist L, Stark B, Engler N, et al. Evaluation of arm and shoulder mobility and strength after modified radical mastectomy and radiother- apy. Acta Oncol. 2004;43(3):280Y283.

2. Rostkowska E, Bak M, Samborski W. Body posture in women after mastectomy and its changes as a result of rehabilitation. Adv Med Sci. 2006;51:287Y297.

3. Crosbie J, Kilbreath SL, Dylke E, et al. Effects of mastectomy on shoulder and spinal kinematics during bilateral upper-limb movement. Phys Ther. 2010;90(5):679Y692.

4. Hojan K, Manikowska F, Molinska-Glura M, Chen PJ, Jozwiak M. Cancer Nurs. 2013 Apr 29. [Epub ahead of print] The Impact of an External Breast Prosthesis on the Gait Parameters of Women After Mastectomy.