Left shoulder blade seam pain with a lump may be caused by local muscle spasm, cyst, infection, soft tissue tumor and other diseases. 1. Local muscle spasm: due to incorrect posture and other reasons can cause local muscle tension, spasm, the patient may appear left scapular crevice pain, feel a lump. 2. Cyst: due to long-term friction and other factors cause local edema, periosteum formation and extrusion of surrounding tissues or accompanied by infection, the patient may appear left scapular crevice pain with a lump. 3. Infection: due to bacteria and other pathogens infecting the soft tissues of the left scapula, patients may have local pain, swelling, fever and other symptoms, when the infection is limited, it may lead to the formation of local abscess, and the patients may have bumps. 4. Soft tissue tumors: such as lipoma, myofibroma and other diseases, the patient’s left scapular stitches pain in the local protruding lumps. Left shoulder blade seam pain has a lump may also have other reasons, it is recommended to consult a doctor in time, with the help of a doctor to clarify the cause of the disease, and targeted treatment or therapy.