Inability of left eyeball to turn left is commonly seen in clinical conditions such as ocular muscle paralysis, orbital swelling, ocular trauma, and thyroid-related ophthalmopathy. Ophthalmic muscle paralysis is commonly seen in motor nerve palsy, abducens nerve palsy, etc. Patients may have diabetes mellitus, cerebral vascular lesions, brain inflammation, traumatic brain injury, brain tumors, etc., which lead to limited outward rotation of the eyeball. Orbital mass squeezes the eyeball, resulting in limited external rotation of the eyeball. Trauma to the eye may result in a fracture of the orbital wall, causing the muscle to become entrapped, resulting in limited external rotation of the eye. Thyroid-related eye disease may cause muscle edema, inflammatory cell infiltration, and later fibrosis, resulting in limitation of eye rotation. The exact cause of the disease needs to be determined by the patient’s physician.