Movement isn’t important...until you can’t...

Grey Cook

 Manipulation of a joint appears to change the instantaneous axis of rotation of that joint (1). It would stand to reason that this change would effect muscle activation patterns (2). Can this be applied to the lower extremity? Apparently so, at least according to this paper (3). 

“...The distal tibiofibular joint manipulation group demonstrated a significant increase (P<.05) in soleus H/M ratio at all post-intervention time periods except 20 min post-intervention (P=.48). The proximal tibiofibular joint manipulation and control groups did not demonstrate a change in soleus H/M ratios. All groups demonstrated a decrease (P<.05) from baseline values in fibularis longus (10-30 min post-intervention) and soleus (30 min post-intervention) H/M ratios. Interventions directed at the distal tibiofibular joint acutely increase soleus muscle activation.”

So, what does this mean?

The peroneus longus contracts from just after midstance to pre swing to assist in descending the 1st ray and assist in supination. The soleus contracts from loading response (medial portion, eccentrically, to slow calcaneal eversion) until just after midstance (to assist in calcanel inversion and supination). 

The tibiofibular articulation is a dynamic structure during gait, and the fibula appears to move downward during the stance phase of gait (rather than upward, as previously thought from cadaver studies)(4), with the distal articulation having a rotational moment (5). 

Consider checking the integrity of these joints, and asuring their proper ranges of motion, particularly in patients with chronic ankle instability (6). A little joint motion can go a long way : ) 

1. The Effect of Lateral Ankle Sprain on Dorsiflexion Range of Motion, Posterior Talar Glide, and Joint LaxityCraig R. Denegar, Jay Hertel, Jose FonsecaJournal of Orthopaedic & Sports Physical Therapy 2002 32:4, 166-173 

2. Decrease in quadriceps inhibition after sacroiliac joint manipulation in patients with anterior knee painSuter, Esther et al.Journal of Manipulative & Physiological Therapeutics , Volume 22 , Issue 3 , 149 - 153

3. Immediate effects of a tibiofibular joint manipulation on lower extremity H-reflex measurements in individuals with chronic ankle instability.Grindstaff TL, Beazell JR, Sauer LD, Magrum EM, Ingersoll CD, Hertel J. J Electromyogr Kinesiol. 2011 Aug;21(4):652-8. doi: 10.1016/j.jelekin.2011.03.011. Epub 2011 May 4.

4.  Dynamic function of the human fibula. Weinert, C. R., McMaster, J. H. and Ferguson, R. J. (1973), Am. J. Anat., 138: 145–149. doi: 10.1002/aja.1001380202

5. Kinematics of the distal tibiofibular syndesmosisAnnechien Beumer , Edward R Valstar , Eric H Garling , Ruud Niesing , Jonas Ranstam , Richard Löfvenberg , Bart A Swierstra  Acta Orthopaedica Scandinavica  Vol. 74, Iss. 3, 2003

6. Effects of a Proximal or Distal Tibiofibular Joint Manipulation on Ankle Range of Motion and Functional Outcomes in Individuals With Chronic Ankle InstabilityJames R. Beazell, Terry L. Grindstaff, Lindsay D. Sauer, Eric M. Magrum, Christopher D. Ingersoll, Jay HertelJournal of Orthopaedic & Sports Physical Therapy 2012 42:2, 125-134