Biomechanical Alignment as a Force-Regulation Outcome: A Mechanistic Framework for Load-Dependent Transition from Compensatory Loading to Threshold Violation

Abstract Background Biomechanical alignment is routinely assessed through visual observation, yet this positional paradigm fails to account for dynamic force-regulation mechanisms governing musculoskeletal behaviour under progressive load. Objective To present the MMSX Alignment Spectrum — a five-grade mechanistic framework classifying alignment based on force-vector trajectories, torque distribution, and tissue tolerance proximity. Methods Narrative synthesis of peer-reviewed biomechanical, orthopaedic, sports science, and motor control literature including EMG, inverse dynamics, and tissue tolerance modelling evidence. Results Alignment is load-dependent. The Grade C-to-D transition represents a critical inflection from performance inefficiency to active injury mechanism activation, undetectable via positional observation alone. Conclusions Alignment is a continuous, load-dependent force-regulation outcome. The MMSX Spectrum provides a scalable, evidence-congruent instrument for injury prevention and performance optimisation.