*Note: This is part of a series of thoughts on the topic of looking at movement and movement related symptoms as influenced by the nervous system. These will be dynamic posts with additional content and references being added as time allows, but the primary purpose of the posts are to share my current thoughts on the influence of manual therapy and exercise on what we see and feel in our patients. I hope others will engage me in these thoughts and provide their perspectives and also criticism into the process.
Post-antalgic Patterning – Part 1 – A Definition
Injury occurs either acutely or cumulatively. A threshold is reached and threat is detected, whether conscious or unconscious, the body wants to protect itself. As a part of the physiologic chemical cascade of events which occurs in an attempt to address the potential structural damage, the nervous system, both central and peripheral, protects the region through numerous responses including localized guarding or splinting. This guarding process involves contractile activation of muscle AND the CONTRACTILE activation of what has previously been defined as inert soft tissue, such as fascia, joint capsules, ligaments (1). As a result, kinematics, arthrokinematics, and tissue dynamics may be altered and movement may change. Some of it is subtle, some of it not (2). Regardless, it appears that occasionally, this alarmed state stays active long after the tissue has healed and the threat removed (3).
Steering away from the complicated matter of pain, better discussed in Explain Pain, I wish to focus on what I call “post-antalgic patterning”. This is the existence of an altered movement pattern that is most often an unconscious behavior that remains long after an injury has been healed, or possibly even perceived injury. It exists anywhere in the body with any movement, not just gait! This pattern is a chronic pattern, which begins as early as 2 weeks after an acute injury and remains a minimum of 6 months or for a multitude of years. It may be associated with patient symptoms through regional interdependence, or it may not. Post-antalgic patterning may resolve spontaneously or it may best respond to touch and/or movement coaching. In this definition, any clinician perceived “dysfunction” of the joint or soft tissue contributing to this movement pattern is propagated by the nervous system, not structural change and is minimally influenced by joint or tissue inflammation or swelling.
This pattern may or may not be mechanically inefficient, and it may, or may not, further propagate future episodes of threat elsewhere in the body. In truth, it may just be what it is. Perhaps changing it makes functional improvements and improved symptoms, perhaps not. This is key, because we really don’t understand it, and we have to know when to just ignore it and have the patient move on with life despite this perceived asymmetry, because in reality, we do not know if it might have always been present. This is important, because you have to put limits on how much you try and attempt to alter, as the concept of a “symmetrical” human is fairly illogical. Rather, the objective is to simply to provide an environment to allow movement in a way that the patient can regain trust in these areas, to become more active, which is where the healing occurs.
Your hands or tools aren’t magic. They may or may not be appropriate to providing that supportive environment for altering this pattern, but if you use them, realize their sole purpose is to get the patient moving, reducing threat and letting the tissue re-accommodate to activity.
To be continued in part 2..
1.) Schleip, R., W. Klingler, and F. Lehmann-Horn. “Active fascial contractility: fascia may be able to contract in a smooth muscle-like manner and thereby influence musculoskeletal dynamics.” Medical hypotheses 65.2 (2005): 273-277.
2.) Crosbie, Jack, Toni Green, and Kathryn Refshauge. “Effects of reduced ankle dorsiflexion following lateral ligament sprain on temporal and spatial gait parameters.” Gait & posture 9.3 (1999): 167-172.
3.) Gribble, Phillip A., et al. “The effects of fatigue and chronic ankle instability on dynamic postural control.” Journal of athletic training 39.4 (2004): 321.