Muscle atrophy in polytraumatized patients - a longitudinal observational pilot study

Area of Science:

• Orthopedics
• Sports Medicine
• Regenerative Medicine

Background:

• Polytraumatized patients exhibit pronounced muscle atrophy compared to healthy immobilized individuals.
• The precise rates and recovery trajectories of acute muscle atrophy in these patients remain under-reported.
• Understanding these changes is crucial for developing targeted rehabilitation strategies.

Purpose of the Study:

• To prospectively investigate the rates and trajectories of acute muscle atrophy in polytraumatized patients.
• To assess changes in muscle thickness, hand grip strength, and inflammatory markers.
• To evaluate muscle perfusion parameters using advanced spectroscopic and Doppler techniques.

Main Methods:

• A prospective longitudinal pilot study involving 10 polytraumatized patients (Injury Severity Score ≥16).
• Measurements included hand grip strength, inflammatory blood markers (CRP, leukocyte count), and skeletal muscle thickness (rectus femoris, vastus lateralis, tibialis anterior) via ultrasound.
• Muscle oxygen saturation, relative hemoglobin content, blood flow, and velocity were assessed using laser-Doppler and white-light spectroscopy.

Main Results:

• Muscle thickness significantly decreased daily across rectus femoris (-0.47%/d), vastus lateralis (-0.39%/d), and tibialis anterior (-0.38%/d).
• Hand grip strength unexpectedly increased at a rate of 0.85%/d, despite muscle thinning.
• Inflammatory markers (CRP, leukocyte count) decreased significantly, while muscle perfusion parameters showed high variability with limited significant changes.

Conclusions:

• Polytraumatized patients experience rapid muscle atrophy, yet grip strength may increase during the acute phase.
• The observed increase in grip strength despite muscle loss warrants further investigation into underlying physiological mechanisms.
• These findings highlight the complex interplay between muscle degradation, systemic inflammation, and functional recovery in severe trauma.