Brief Answer:
could be because of muscular or musculoskeletal.

Detailed Answer:
Hi,
Welcome to health care magic,

I have read your query and understand your concern.

Here, I would like to know that,

Since how many days you are having this pain?
Is there any other symptom associated with this pain?
Also ,let me know whether you have any history of diabetes or thyroid illnesses or any injury to that joint.

The left shoulder blade pain could be because of muscular or musculoskeletal origin,the first possibility comes in my mind.

But I will also want to rule out the chances of rotator cuff injury or tear or rotator cuff tendinitis (inflammation of its tendons) by taking complete medical history and clinical examination.

However,you may try below measures and symptomatic treatment for some relief.

1. Avoid repetitive overhead activities by the left hand especially.

2. Do not carry any heavy object or bag on your left shoulder or arm.

3. Apply ice packs for about 15 minutes twice or thrice daily.

4. Apply diclofenac based topical ointment and see if gives relief or not(available over the counter)

5. You can take also oral pain killers (ibuprofen or aleve) if pain is severe or topical application does not give relief.

If still pain is persisting even after 2 to 3 days of this symptomatic treatment,then proper examination of shoulder blade along with shoulder joint is required to find the exact cause and if needed x ray and MRI should be done.

You can consult nearby doctor or orthopedician who can write x-ray and MRI scan of the shoulder after taking complete history and thoroughly clinical examination.

Hope this information will help you.

Thanks and Regards,

Dr.Sandip Kabra.

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