There are no consistent diagnostic criteria for Pisa syndrome , but an arbitrary cutoff of at least 10° of lateral flexion has been adopted in most investigations.(4) Drugs, including antiparkinsonian drugs, may induce Pisa syndrome. The pathophysiology remains poorly understood but the tendency to lean is associated with more severe motor involvement, combined treatment with levodopa and dopamine agonists, gait disorders, and such comorbidities as osteoporosis and arthrosis.(2) Pisa syndrome may come on either acutely or subacutely associated with medication adjustments, or gradually in a way that seems related to the evolution of the disease.(3) Either acute or subacute presentations seem to be pure abnormalities in the coronal plane and are usually reversible. A more chronic form may occur in association with camptocormia. The acute/subacute phenotype is the condition originally named Pisa syndrome.
Oliver Sacks discussed Pisa syndrome in the story On the Level in The Man Who Mistook His Wife for a Hat and Other Clinical Tales.(5)
This patient with PD tended to lean to the left (Figure).
1. Campbell WW. Clinical signs in neurology : a compendium. Philadelphia: Wolters Kluwer Health, 2016.
2. Tinazzi M, Geroin C, Gandolfi M, et al. Pisa syndrome in Parkinson's disease: An integrated approach from pathophysiology to management. Mov Disord. 2016;31:1785-1795.
3. Michel SF, Arias Carrión O, Correa TE, et al. Pisa Syndrome. Clin Neuropharmacol. 2015;38:135-40.
4. Barone P, Santangelo G, Amboni M, et al. Pisa syndrome in Parkinson's disease and parkinsonism: clinical features, pathophysiology, and treatment. Lancet Neurol. 2016;15:1063-74.
5. Sacks, O. The man who mistook his wife for a hat. London. Duckworth, 1985.