here the pain for left shoulder blade and under the chest can be related to 2 things first it can be due too heart problem or it can be due to cervical spine problem check if patient have pain under the chest while walking up stairs or going up hill along with breathing difficulty then it might be related to heart and you need to see cardiologist and should go ahead with electrocardiogram as well treadmill test if both this test comes normal then he can check weather he have pain radiating from ceck to hand along with numbness in hand in that case it can be related to lower cervical spine and i suggest to visit orthopaedic and go ahead with x ray or mri of cervical spine. as per the report here orthopadic will suggest for conservative management with medication and physiotherapy or else surgical managemenI for sever spinal or disc related problem. suppose if there is no much issue then he can also check with physio after doing all testing. Here physio will guide him with few stretching and strengthening exercise to improve further. Along with this also take physiotherapy treatment to relax soft tissues and increase healing effect in soft tissue. you can also use hotpack frequently at home to have some more relaxing effect on your soft tissues this should be used mainly on painful area near to spine. Take care.