#peronei

We have been saying this over and over, sorry for the repeated nature of this concept. But ankle sprains should not be taken lightly. This study showed: "Conclusions: Individuals with unilateral FAI had increased error ipsilaterally (injured limb) for inversion movement detection (kinesthesia) and evertor force sense and increased error contralaterally (uninjured limb) for evertor force sense."

No only do they have loss of kinesthesia on the injured side, but this presents along with a reduced evertor force sense as well as contralateral processing deficits. The Brain is paying close attention to the first things that hits the ground, and noting how stable/unstable it is. Ankle sprains cannot be taken lightly, even the mild ones. Plus, do not forget about the corruption of the frontal plane at the hip that often occurs after these events.

 Bilateral Proprioceptive Evaluation in Individuals With Unilateral Chronic Ankle Instability

Andreia S. P. Sousa, PhD; João Leite, BSc; Bianca Costa, BSc; Rubim Santos, PhD

Escola Superior de Saúde do Porto, Centro de Estudos de Movimento e Actividade Humana, Instituto Politécnico do Porto, Portugal

More peroneii action! In folks with chronic ankle instability, it contracts earlier, longer (throughout stance phase) but not stronger...This article looks at activation times and patterns of folks with chronic ankle instability. 

One should never wonder why repeated ankle sprains occur. We have hit this topic hard in the past.  Chronic Ankle Instability (CAI) clients exhibit prioprioceptive and postural control challenges. According to this article, additionally, CAI clients have gait. 

"Time of activation for all muscles tested occurred earlier in the CAI group than in the control group. The peroneus longus was activated for a longer duration across the entire stride cycle in the CAI group."

"Individuals with CAI demonstrated neuromuscular-activation strategies throughout the lower extremity that were different from those of healthy control participants. "

Did you see our trademark "goto" exercise in yesterday's social media Facebook blog post ?  It is a keeper if you ask us.  Don't ignore chronic peroneal challenges, they will come back to haunt you.

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Lower Extremity Muscle Activation in Patients With or Without Chronic Ankle Instability.  Mark A. Feger, MEd, ATC; Luke Donovan, MEd, ATC; Joseph M. Hart, PhD, ATC; Jay Hertel, PhD, ATC, FNATA, FACSM Department of Kinesiology, The University of Virginia, Charlottesville

http://www.natajournals.com/doi/abs/10.4085/1062-6050-50.2.06 

Results:  Time of activation for all muscles tested occurred earlier in the CAI group than in the control group. The peroneus longus was activated for a longer duration across the entire stride cycle in the CAI group (36.0% ± 10.3%) than the control group (23.3% ± 22.2%; P = .05). No differences were noted between groups for measures of electromyographic amplitude at either preinitial or postinitial contact (P > .05).

Trade Secret: Proper Calf Raise

We are selling off part of the farm here today in giving this one away.  This is an exercise we prescribe frequently.

When we rise up onto the ball of the foot, most clients and patients tend to come up and either be flush on the forefoot bipod or even a little more onto the lateral aspect of the forefoot. When asked, rarely do we hear that they have a majority of pressure over the medial half of the forefoot. This posturing tendency can lead to inversion sprains. Imagine for a minute a basketball or volleyball player, or any sport for that matter, because most involve the foot leaving the ground and returning to it.  When the foot returns to the ground, if the foot is even a slightly bit inverted (meaning they are even slightly tending towards landing on the outer half of the forefoot) an inversion sprain is at risk. This is particularly so when the lateral gastroc-soleus is weak and the peronei are weak. Forefoot valgus foot types are certainly in the risk category here and so once again we find that knowing your foot types so you can help your clients is need-to-know information.  Back to our jump and to the return to the ground from the jump, you must remember that the metatarsals are shorter and shorter as you move to the lateral foot. This means that if the load is moving laterally because of posterio-lateral compartment weakness as described above, that the sheer design of the shorter lateral metatarsals will continue to press the motion laterally. This is one of the reasons why lateral ankle strains, inversion sprains, are so frequent and repetitive (we have described the other factor in the latency of the peronei after a single inversion sprain in other blog posts here). 

So here we have our calf raise exercise. Squeezing the ball between the ankles on the up (concentric phase) and on the down phase (eccentric) with a nice isometric at the top will force the weight bearing onto the first and second metatarsals (medial forefoot) and drive the lateral compartment to press the motion medially through an isometric instead of depending so much on this compartment to protect the inversion motion through and eccentric.  We find this motor pattern terribly weak in our athletes, especially our jumping sports and certainly after inversion sprains. IF we can provide more strength to hold this medial posture during the return to the ground from a jump we can slow or delay the lateral inversion event risk.  The key to the exercise is to keep the pressure into the ball medially at all times. A wonderful additional benefit to this exercise is that the user will feel the cocontraction of the thigh adductors which further provides a medial stability effort and blends nicely with the lower abdominals.