Relation between posture and spine and pelvis flexibility: a systematic review

Abstract Introduction: Changes in body structure positioning are associated with muscle flexibility and joint mobility, but evidence of this relationship is still incipient. Objective: To identify evidences of correlation between parameters regarding static body posture in orthostasis and spine and pelvis flexibility and/or mobility. Methods: Systematic review guided by the PRISMA Statement and the recommendations of the Cochrane Collaboration (PROSPERO: CRD42015026298). A search of the BIREME, EMBASE, PubMed and Science Direct databases was carried out, considering the beginning of the databases until January 16, 2017, with the terms and Boolean operators “posture” AND “spine” OR “pelvis” AND “range of motion, articular” OR “movement”. To be included in the review, studies should present observational or clinical trial methodological designs, have sampled healthy individuals, present correlation or association test results between static posture and mobility/flexibility in the sagittal plane, and be published in Spanish, English or Portuguese. The methodological quality was evaluated by the Downs & Black scale and evidence by the GRADE system. Results: A total of 5,326 studies were obtained, seven of which were included after the establishment of the eligibility criteria. All studies presented high methodological quality, although a considerable heterogeneity regarding the choice of instruments and evaluation protocols was noted, reflecting contradictory results. Therefore, the present systematic review presents a moderate strength of evidence. Conclusion: No definitive evidence is yet available concerning the possible relationship between body posture and spine and pelvis flexibility and mobility.