Task Force Consensus on Nosology and Cut-Off Values for Axial Postural Abnormalities in Parkinsonism

Background There is no consensus with regard to the nosology and cut-off values for postural abnormalities in parkinsonism. Objective To reach a consensus regarding the nosology and cut-off values. Methods Using a modified Delphi panel method, multiple rounds of questionnaires were conducted by movement disorder experts to define nosology and cut-offs of postural abnormalities. Results After separating axial from appendicular postural deformities, a full agreement was found for the following terms and cut-offs: camptocormia, with thoracic fulcrum (>45 degrees) or lumbar fulcrum (>30 degrees), Pisa syndrome (>10 degrees), and antecollis (>45 degrees). "Anterior trunk flexion," with thoracic (>= 25 degrees to <= 45 degrees) or lumbar fulcrum (>15 degrees to <= 30 degrees), "lateral trunk flexion" (>= 5 degrees to <= 10 degrees), and "anterior neck flexion" (>35 degrees to <= 45 degrees) were chosen for milder postural abnormalities. Conclusions For axial postural abnormalities, we recommend the use of proposed cut-offs and six unique terms, namely camptocormia, Pisa syndrome, antecollis, anterior trunk flexion, lateral trunk flexion, anterior neck flexion, to harmonize clinical practice and future research.