Earticle

초록

영어

Individuals with neurological impairments often develop various compensatory gait strategies that may exacerbate asymmetries and increase fall risk, yet the precise causal relationships between specific muscle deficits and compensatory patterns are not fully understood. This study employed predictive neuromuscular simulation to isolate the pure effects of unilateral plantar flexor weakness on gait compensation mechanisms. Using a three-dimensional musculoskeletal model (9-link, 14-muscle) with reflex-based control, we systematically reduced paretic plantar flexor strength (gastrocnemius and soleus) to 80%, 60%, 40%, and 20% of normal while maintaining all other muscles at full strength. Dynamic optimization algorithms (CMA-ES) generated optimal gait patterns under energy efficiency and stability constraints. Results demonstrated that paretic gastrocnemius activation decreased to 23.5% under severe weakness (20% condition), while paretic soleus exhibited counterintuitive hyperactivation (3-fold increase) under moderate weakness conditions. Kinematic adaptations included increased paretic ankle dorsiflexion (3.7-fold increase) and hip flexion angles reaching 23.5°, consistent with clinical hip strategy patterns. Joint loading analysis revealed systematic distal-to-proximal redistribution, with 36.4% reduction in paretic ankle loading while hip loading remained stable. Bilateral compensations emerged, with non-paretic limb showing 41.3% ankle loading reduction. These simulation results demonstrate that complex gait compensations can emerge solely from plantar flexor weakness, without requiring additional neurological impairments. The threshold-dependent, nonlinear nature of adaptations supports precision rehabilitation approaches targeting individual impairment profiles rather than generic symptomatic treatments.

목차

Abstract
Ⅰ. Introduction
Ⅱ. Methods
1. Model and controller
2. Objective function
3. Optimization algorithm
4. Experimental conditions
5. Outcome measures
Ⅲ. Results
1. Neuromuscular activation adaptations
2. Phase-specific muscle activation changes
3. Kinematic compensations
4. Joint loading redistribution patterns
Ⅳ. Discussion
Ⅴ. Conclusion
References

키워드

저자

• Dong-Kyun Koo [ Regional Innovation System & Education Project Team, Industry-University Cooperation Foundation, Wonkwang Health Science University ] Corresponding Author
• Seo-Yoon Park [ Department of Physical Therapy, College of Health and Welfare, Woosuk University ]

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  한국신경근육재활학회지 [Korean Journal of Neuromuscular Rehabilitation]

• 간기

  계간

• pISSN

  2508-6456

• 수록기간

  2011~2026

• 등재여부

  KCI 등재

• 십진분류

  KDC 514 DDC 617