Equilibrium Analysis for the Forces in the Human Spinal Column and Its Musculature

TLDR

Equilibrium equations for the thoracic and lumbar spine incorporate body weight, external load, muscle forces, and intervertebral reactions. The study examines the effects of three orthotic devices on muscle forces in a scoliotic patient. The authors solve the equilibrium equations using linear programming to minimize total force and assess how the orthotic devices alter muscle forces. Numeric muscle force and intervertebral reaction values for progressive forward flexion and lateral bending are presented, illustrating the influence of the orthotic devices.

Abstract

The equations of equilibrium are set up for the thoracic and lumbar spine and involve body weight, external load, muscle forces, and intervertebral reactions. These equations are solved using a linear programming technique that minimizes the total force in the system. The solution gives numeric values for the muscle forces and intervertebral reactions. The results for a subject in progressive forward flexion and in lateral bend are presented. Also examined are the effects of three different orthotic devices on the muscle forces of a patient with a scoliotic spine.