New Proposal in the Approach to Brachial Remodeling: The Melfa-Anastasia Arm Laxity System (MAALS).

BACKGROUND: Current diagnostic tools for upper arm laxity assessment-including the pinch test and two-dimensional photographic scales-fail to characterize the underlying tissue composition, leading to inappropriate treatment selection and preventable complications. OBJECTIVES: To introduce the Melfa-Anastasia Arm Laxity System (MAALS), a precision medicine framework integrating high-frequency ultrasound (HFUS) biometry with a cylindrical geometric model for objective, compositional assessment of brachial architecture. METHODS: MAALS employs a noncontact stand-off technique (HFUS, 18-22 MHz) to measure superficial adipose tissue thickness (SAT) and triceps muscle thickness (M) at the mid-brachial sentinel point. Two dimensionless indices are derived: the adipose saturation percentage (%SAT = SAT/Rtot × 100) and the muscle filling ratio (MFR = M/Rtot), where Rtot is the total brachial radius calculated from arm circumference. RESULTS: Based on preliminary anatomically rational thresholds, MAALS defines five phenotypes (0-4): normotrophic (0), adipose hypertrophy (1), mixed morphology (2), pure cutaneous ptosis with critical vascular risk zone (%SAT < 20%, SAT < 4-5 mm; liposuction contraindicated) (3), and sarcopenic/atrophic (4). Each phenotype carries specific therapeutic indications ranging from prevention to regenerative strategies. CONCLUSIONS: MAALS is presented as a conceptual precision medicine framework requiring prospective validation, not as an established clinical standard. By providing objective compositional characterization of brachial architecture, it offers a structured basis for safer, more individualized treatment planning, future multicenter validation studies, and integration with AI-based segmentation technologies.