So, from my little ditty, I know you are thinking, “Ah, I bet the splenius is located in the neck and possibly along the top line as it helps with the outline?”  Well, you’d be right!

It originates from the thoracic vertebrae, notably vertebrae 3-5, the dorsal scapula ligament and the nuchal ligament inserting into the cervical vertebrae, 3-5 again, the atlas and the nuchal crest.  Although it is a superficial layer muscle, it is worth noting its origins slot under the cervical trapezius.  The picture above shows it highlighted in yellow.

The splenius is responsible for elevating the head and extending, straightening and laterally flexing the neck.

When the splenius gets tight or injured you may find your horse is trying to avoid movements to the opposite side. 

 For example, when ridden they may want to pull their head towards the side that is sore to prevent the tight side of the muscle stretching and relieve tightness.  When they are resting, they may stretch their neck downwards for prolonged periods to relieve the discomfort.

During treatment you will see me using a lot of petrissage movements including kneading with thumbs and skin rolling, these loosen the fascia from the muscle and help return flexibility to the area.  A good indication of a tight splenius shows up during the palpation stage of the treatment when there can be a knot at the insertion side of the muscle causing the horse to react by swiftly moving his head away from the pressure.

A sore or tight splenius can be due to rider imbalance, hanging heavy on one rein or sitting unevenly in the saddle.  It is prevalent in dressage horses from holding their fantastic outlines for prolonged periods, especially when a lot of elevation and flexion is required – think half pass, extended trot etc.  If you want to work these moves, ensure your horse is fit and strong enough to balance himself equally through his body while he performs them. 

As with all muscles, make sure the splenius gets thoroughly warmed up and cooled down after work – stretches are really useful for this muscle, preventing it from knotting up and allowing more blood flow through the belly of the muscle.  Think about how your neck and upper back feels when you stretch your head down after sitting at the computer for too long, feels good right?

An under developed splenius can make the horse appear ewe-necked but with the correct work carried out regularly it can easily be improved.

Have a look at the 3 images of the horses attached, these really highlight how the splenius works and how it can be harmed from hyperflexion.  My favourite is the collected western, how happy does this horse look?

Remember, all the horse’s muscles work as one unit, and the root cause of splenius issues can stem from issues elsewhere in the body as the horse learns to compensate his way of going to reduce pain.

If you suspect your beloved friend has any issues with this, or any muscle, please don’t attempt to treat it yourself, give your local registered therapist a call and get it sorted professionally.