Rationale: The Pisa syndrome (PS) is defined as a kind of reversible postural deformity which causes a lateral trunk flexion of 10 degrees or more. A prevalence of approximately 7.4% to 10.3% of patients with Parkinson disease (PD) also have PS. Though unbalanced function of the basal ganglia network and impaired visual-spatial functions including parietal cortices in PS is known, the pathophysiology of PS remains to be unclear. Patient concerns: A 67-year-old male patient with PD visited our Rehabilitation outpatient department because of his trunk which involuntarily deviated to the left side when he stood up. Diagnoses: Based on the history, physical examination, X-ray images, Tc-99m brain TRODAT-1 single-photon emission computed tomography (SPECT), and regional cerebral perfusion Tc-99m ethyl cysteinate dimer SPECT, the patient was diagnosed with PD with PS. Interventions: The patient refused our recommendation of admission for pharmaceutical treatment due to personal reasons and was only willing to accept physical training programs at our outpatient department. Outcomes: We arranged functional neuroimaging of the brain to survey possible neurologic deficits. The patient's images of ethyl cysteinate dimer SPECT and TRODAT SPECT showed abnormalities, including hypoperfusion and diminished dopamine transporter uptake, in the areas of the basal ganglia network and other brain regions. Lessons: Based on previous literature and the imaging of our patient, we hypothesize that PS results from unbalanced function of the basal ganglia network and impaired visual-spatial functions of bilateral parietal cortices.
