Sternocleidomastoid & Trapezius Pain

I noticed around lunchtime today that after doing the compound lifts workout the sternocleidomastoid muscle on the left side of my neck and trapezius was sore and very tight probably aggravated while doing 4 sets of deep deadlifts with 60kg.  If these muscles were pulled while doing this exercise were they over tight before exercise and stretched to the point of damage?

Would this damage caused by over tight muscles be typical symptoms of ‘X Syndrome‘?  Further investigation required.

 

Later in the afternoon while lying down I still had pain in the left hand sternocleidomastoid neck muscle and trapezius.  When I pinched the sternocleidomastoid muscle it felt solid, very tight and sore.  On pinching the trapezius muscle I felt pain shooting down the left hand side of my back into my scapula.

I also noticed in mirror that the left hand trapezius was taught!  Pinching the trapezius with the left hand caused the left hand shoulder crunch.

The right hand shoulder was also tight when stretching in the doorway.

Further evidence of ‘X Syndrome‘?

Remedy:-  Continual stretching and massage of all related muscles to free up chest muscles, shoulders, scapula and neck.