The Trapezius is a big muscle in so many ways – big in area, in strength, in the number of things it does and in the amount of trouble it can cause
So, lets have a brief look at each of those elements of this important upper body muscle
Basic Anatomy
The muscle is a very satisfying diamond shape and it’s name refers (derived from Greek) to its four sided nature. It sits at the top of the back and attaches to the skull, the spine, the collar bones and the shoulder blades. I’ve chosen this particular picture of it because it gives a flavour of the complexity of the back and the sheer number of other muscles that are there too!
Detailed Anatomy
The upper portion attaches to the skull and all of the cervical (neck) vertebrae the (spine of the) shoulder blade at the other side
The middle portion attaches to the last cervical vertebra and the first few thoracic (mid back) vertebrae and at the other end, the shoulder blade and outer collar bones. This is important not really well represented in most of the pictures – the Trapezius extends to the front of the body via its attachment to the collar bones and can thus influence its position, even though we think of it , rightly as a back muscle.
The bottom portion attaches to the bottom half of the thoracic vertebrae and the spine of the shoulder blade
Muscle Action
There are quite a few. Here goes…
Shoulder Blade Movements
Elevation (raising up) of the shoulder blades
Depression (drawing down) of the shoulder blades
Retraction (squeezing together) of the shoulder blades
Upward rotation of the shoulder blades which gives you a side arm raise & over head reach
Overall stability of the shoulder blades – that is, generally keeping them in the right place, on top of the ribcage.
Movements of the Skull
Bending back (extension ) of the neck and head
Side bending of the skull and neck. In this action the halves of the muscle work separately to each other
Rotation of the skull and neck. In this action the halves of the muscle work separately
Overall stability of the skull – that is keeping it in place. This is crucial because the head is heavy!
Movements of the Spine
Bending the neck (and skull) backwards
That’s All Very Well, but that does that mean for day to day movement?
If you look up muscle anatomy online then always you get a picture, info about where the muscles attach to bones and joints, and what actions the muscle brings about.
But, well, so what? I have had to really think about this
Why should we care about the Trapezius?
It works very hard indeed to stabilise the head and allows us to move it in lots of different directions. That alone should encourage us all to respect and take care of the Trapezius!
It has to over work to account for poor posture and movement patterns. This can then lead to pain and discomfort
Weakness in other muscles can necessitate that the Trapezius helps out with other stuff (notably compensating for weakness in the Rotator Cuff muscles, the little muscles that stabilise the shoulder joint) and this will overwork the muscle and lead to pain and discomfort.
It does contribute to arm movements and in particular when you shrug your shoulders and lift your arms and when you elevate your arms over your head or out to the sides. These aren’t the obviously crucial arm movements when you think about strength training, but, in daily life we don’t do precise, well defined arm movements we do blended complex mixtures of movements which are then disturbed by injury. Think of how often you take your arm over your head – brushing your hair, buttoning a top at the back, reaching from a high shelf.
OK then so now let’s think about Posture
Anyone heard of text neck? There have been lots of images doing the rounds on Social Media showing the number of kilos of pressure exerted on the neck if the head is relatively forward. I’m not sure how much of the scare mongering is actually true, and what the real risks to posture are of leaning the head forwards to “meet” the phone, however, the human body does definitely obey the laws of physics and if the neck is curved forwards as opposed to being straight up, then gravity will pull the head even further downwards.
The muscles at the back of the neck/upper back have to overwork to prevent that and not least because we are eye dominant in our behaviour and subconsciously we want to be able to see forwards and so we will correct for the tendency to loll the head forwards. One of the principle muscles that have to over work, over contract to stop this lolling is the Trapezius. There is a cost to the efficiency of the muscle and an overall energy cost to the body. We have to “waste” muscle energy and time on maintaining this poor position – energy that could be better spent in walking or running. The overworked muscle can get achy, tight, tender, and “locked” into it’s overworked position required to try and support the head.
Don’t send many texts? You are not exempted… yet! Do you slouch in a chair? When we round the back into a curve – maybe you’re doing it right now… then the head tends to get “left behind”. Marooned in a forwards position, again, possibly due to the subconscious need to have the eyes forwards at all time.
Weak Rotator Cuff Muscles
There are four Rotator Cuff muscles that are responsible for the stability of the shoulder joint. The joint is very shallow (compared to the hip or the spinal vertebrae) which allows for a big range of arm movements. Stability is via muscles and tendons and in particular the Rotator Cuff. They are prone to over use, under use and injury and for certain movements the Trapezius will compensate for poor Rotator Cuff Action. For this, and for any action really, the Trapezius need strength in range and it can be strengthened doing side arm raises, Shoulder shrugs with straight or bent elbows or by walking the arms up a wall. We generally think that shrugging the shoulders is a bad thing, but it depends upon what the context. Chronically elevating your shoulders for no reason other than habit or as a unconscious reaction of stress is a bad thing. Loading the Trapezius muscle , elevating the shoulder blade and then releasing it down so that the muscle works to resist gravity is a bona fide exercise and a good thing!
A Right Pain in the Neck
Some neck pain is caused by tight neck muscles and/or chronically elevated shoulder blades. (Mind you, chronically elevated shoulder blades can be caused by a tight chest. Nothing is ever simple with the human body….)
The pain can manifest in various different ways – in the neck itself, radiating down into the mid back or out into the shoulders, and or in the skull and can present as chronic headaches.
In addition, muscle over-tightness and overwork, or even just normal muscle work and lead to the development of Trigger Points . These hot spots of irritation within the muscle (any muscle) and arise in the same place in the muscle every time and cause a predictable pattern of referred pain. This is definitely the case with the Trapezius
There are gentle, safe ways of addressing pain and tightness but if the discomfort doesn’t resolve then it is well worth considering seeing a Physiotherapist or Osteopath to get checked out
Here are three ways to help the Trapezius back to good health
One is a neck stretch, one shows a couple of ways to strengthen the muscle, and one shows how to self massage the muscle.