BIOMECHANICAL IMPACT OF MILD LOWER LIMB LENGTH DISCREPANCY

Abstract

Discrete lower limb length discrepancy, characterized by small differences in length between the extremities, may have relevant effects on gait biomechanics, posture, and musculoskeletal load distribution, although it is often underestimated in clinical practice. The present study aimed to analyze, in light of the scientific literature, the main biomechanical effects of discrete lower limb length discrepancy in healthy individuals, with emphasis on its functional repercussions and clinical relevance. This study consists of a narrative literature review of an exploratory and descriptive nature, with a qualitative approach, conducted through searches in the PubMed/MEDLINE, Scopus, Web of Science, SciELO, LILACS, and Virtual Health Library databases, covering publications from 2010 to 2025. The findings demonstrate that even discrepancies of small magnitude may produce measurable biomechanical alterations, including gait asymmetry, pelvic tilt, compensatory joint adaptations, and changes in plantar support behavior. It was also observed that compensatory mechanisms adopted to preserve locomotor stability and functionality may favor asymmetric load redistribution and progressive musculoskeletal overload over time. Furthermore, the literature reveals heterogeneity regarding the clinical threshold of relevance for limb length discrepancy, indicating that its interpretation should consider, in an integrated manner, the magnitude of the discrepancy, individual adaptive capacity, and the functional and clinical context of each individual. It is concluded that discrete lower limb length discrepancy should not be automatically considered a condition of low clinical relevance, since small discrepancies may generate cumulative biomechanical repercussions, with implications for functional assessment, prevention, and the planning of therapeutic interventions.