Manual Therapy: What is REALLY going on?

Earlier in my PT career I often called B.S. on forms of treatment that didn't seem to pass the smell test. Manual therapists in particular seemed susceptible to jumping on the bandwagons driven by chiropractors (i.e. adjustments, active release therapy, and craniosacral therapy). Not only did I try to avoid any professional association with whom I perceived as quacks, I went out of my way to disprove their methods. As you can imagine, telling someone who believes in Santa Clause "there really isn't a Santa Clause" doesn't always sit well. In fact, it made me downright unpopular with a few folks within our profession.

Being married for ten years has given me some amazing clarity with respect to how I see things. I have come to realize my relationship with my wife would never evolve without intense introspection prior to any external scrutiny I was ready to dish out in her direction. This process has allowed our relationship to blossom into something I could never have dared imagined cultivating on my own. Sitting on my front porch this morning reflecting on our journey, I had another moment of clarity: The evolution of my clinical reasoning and decision-making must precede any relevant criticism of another's.

While I think this process has subconsciously been taking place for a little over a year now, becoming aware of it really had an effect on me. I have been devouring books and peer-reviewed literature in mass quantities. Like my marriage, it has been a transforming journey. More so, the journey makes me realize just how much good work has been done within the fields of movement science. It also motivates me to think we have the opportunity to be a part of the next evolution.

Mechanisms of Manual Therapy

My motivation in writing this post, came from an article in Manual Therapy by Joel Bialosky and associates from the University of Florida. The article provides a framework of manual therapy that has yet to be previously defined to this degree.

Proposed mechanisms for manual therapy vary considerably among our colleagues. A consistent theme however is the identification and correction of biomechanical faults within the musculoskeletal system. This paradigm has been with us for some time and continues to be refined in the peer reviewed literature. However as more evidence emerges, we are discovering there is much more to our manual techniques than correcting upslips and stretching joint capsules.

In an effort to address what "more" there is to our techniques, Bialosky et al provide an elegant proposal of five potential mechanisms at play when our hands are on the patient.

Mechanical Stimuli: Our hands are capable of inducing temporary mechanical changes within connective tissue, but the lasting effects are still uncertain. We have seen positive effects from our manual techniques and assumed a mechanical response to our mechanical technique, but it may not be that simple.

Neurophysiological Mechanism: There is clearly an interaction between the peripheral and central nervous systems during manual therapy. Hypoalgesia and changes in sympathetic activity following joint mobilization technique have been consistently documented in recent literature. Notably the changes in pain threshold and sympathetic activity often occur distant to the site of the manual technique. Something within the patient is clearly interested in what we do!

Peripheral Mechanism: Local tissue injury sets off a cascade of events both near and far within the body. Manual therapy has been recently shown to reduce inflammatory chemicals such as cytokines and substance P along with increasing systemic opioid release. The "good feelings" associated with manual therapy have often been attributed to correction of mechanical faults, but peripheral mechanisms may provide a more reasonable description the therapeutic effect.

Spinal Mechanisms: Renown pain physiotherapist David Butler refers to the spinal cord as an amplifier for sensory modalities. Manual interventions have been recently implicated in modifying both afferent and efferent activity within the spinal column. The bottom line is that the spinal column isn't simply a conduit, but an active participant in determining the effects of manual care.

Supraspinal Mechanisms: Admit it. There have been times where we've thought privately that a condition or response to treatment was "all in the patient's head". Turns out there may be more truth to this statement than we'd previously imagined. Recent animal and human studies implicate specific regions of the brain in mediating the pain experience. Moreover psychosocial factors such as patient expectation and placebo are very likely to affect the outcome of our manual intervention.

Time for Change?
I can't even begin to tell you how sick I am of this word in 2008, but in this case it is appropriate. The moment our hands come in contact with a patient, their nervous system is instantly interested in what's going on. Not only that, but it will play a major role in determining the outcome of the intervention. Once we've gotten used to this idea (and it does take some time), how do we take advantage of it in our treatments? I'd really like to hear your thoughts and am getting excited for 2009!


J BIALOSKY, M BISHOP, D PRICE, M ROBINSON, S GEORGE (2008). The mechanisms of manual therapy in the treatment of musculoskeletal pain: A comprehensive model Manual Therapy DOI: 10.1016/j.math.2008.09.001