A 35-year-old male presents with diplopia following a motor vehicle accident two years ago. Examination shows a 25 prism diopter (PD) right hypertropia (left hypotropia) with inability to elevate the left eye in either the adducted or abducted position. CT scan shows that the orbital structures are normal and there is specifically no evidence of an orbital fracture. The patient complains of diplopia and a chin-up head posture and desires surgical correction. What do you think could be going on?