I was recently listening to the recap of a case study presentation about a younger woman we’ll call Kim who was presenting to a physical therapy clinic. Amongst the clinical assessment, the presenter noted both that Kim had an increased kyphosis and that she was recently divorced. The presenter then noted that it’s no wonder Kim’s husband left as that kyphotic curve was just really ugly.
This was, of course, just for comedy and effect, but it made me think about the chicken or the egg of this particular scenario. Was the kyphosis really the problem or was it the underlying stress and loss of confidence that ultimately led to the kyphosis and pain state? What is the influence of posture and emotion or movement and pain?
I, of course, can only speculate as to Kim’s issues, however, the stress and emotional state cannot be discounted. Yes, mechanics are valuable. Yes, mechanics are local, testable, specific, and don’t lie, but the subjective component still matters. Posture and emotion are intricately linked, perhaps by two-way street.
Roether and staff demonstrated that both posture and movement velocities are vital in emotion perception. Sadness was associated with head inclination and anger resulted in more systemic flexion in the study (2009). Inquiry into Kim’s condition may have revealed that she was experiencing one or both of those emotions and increased kyphosis could be a result. Gellhorn argues that these changes may have a detailed association with SNS activity or PSNS withdrawal (1964), which are associated and measured by heart rate variability in times of stress and worry like during Kim’s divorce (Pieper, 2010).
Research by Michalak and colleagues further demonstrated that gait in majorly depressed inpatients was slower, more lateral sway demonstrated, and reduced arm swing. The same study also demonstrated that musical mood induction using sad music in healthy (non-pathological) undergraduate students resulted in the same alterations in gait patterning (2009). Clearly, the objective assessment can be influenced simply by the state of the individual.
Alternatively, one could argue that simply being placed in a position of increased kyphosis–the embodiment of the emotions of sadness and anger–Kim’s muscle tension would increase and subsequently Kim’s mood state may change and pain would follow. Individuals who adopt certain postures begin to, over time, adopt the associated mood state (Niedenhal, 2007). These changes can be detected both by behavior associated with the emotion or by specific changes in the autonomic nervous system. For example, subjects reading cartoons with a pen between their teeth, which activates a number of “smile muscles,” rate cartoons to be much more funny compared to subjects prevented from smiling (Stack, 1988). Perhaps it was Kim’s kyphosis that made her so difficult to be around after all?
Understanding the complete picture is hugely important in helping people and making the right referral if necessary. Those who score toward the depressed end of the BDI scale demonstrate weaker outcomes following knee replacement at 1 and 5 years (Brander, 2007). Dr. Liebenson makes an argument in Rehabilitation of the Spine, too, that the emotional state of the individual plays a profound role in the development of chronic pain, which means it is extremely valuable to screen whenever possible. A variety of tools and pre-screen questionnaires exist to help pick this information out so you can make the right choices.
It is also valuable to understand that both posture and emotion are linked and both impact each other. If one leads to the other and the transitive property is true, both mechanistic and psychological views still win, I just have a difficult time seeing them being as effective as both views combined. It is further evidence, too, that regardless of whose glasses you look through–operator or interator–it’s all the same system.
In months to come, there should be some good data emerging that looks at movement variability and its relationship to heart rate variability in healthy populations that may help guide monitoring and programming that allows a more complete picture and better treatment, too.