How could you treat chronic muscle tension/strain of the rhomboid?

Relax. A program of flexibility and stretching e.g. Yoga can help. Chronic tension in this area can also be referred from the neck, in which case an x-ray can be revealing. Finally, this can be a sign of general stress in your life. Make sure there isn't something going on in your life that may be driving this specific muscle issue for you.
Stretch. Because the rhomboid muscles are between the shoulder blades, usually doing stretching by hugging yourself by crossing your arms. Massage therapy, along with nsaid's and moist heat will also be benificial. Good luck.

Related Questions

How can you treat chronic muscle tension and/or strain of the rhomboid?

Therapies. Chronic musclular pain may respond well to moist heat. Apply for 20 minutes and then stretch the muslce after the heat application. Other options may include: muscle relaxants, physcial therapy, trigger point injections or therapeutic massage. Your physician can evaluate you to determine the best treatment. Read more...
PT or chiro. Nsaids for pain and some musculoskeletal work inclusive of soft-tissue massage, estim or ultrasound prn, and correction of any muscle imbalances. Who does the soft tissue work is up to you. I usually prescribe pt, but a chiro can likely do much of this as well. Read more...