Evaluation of Stiffness of the Spastic Lower Extremity Muscles in Early Spinal Cord Injury by Acoustic Radiation Force Impulse Imaging

Abstract

ObjectiveTo investigate intrinsic viscoelastic changes using shear wave velocities (SWVs) of spastic lower extremity muscles in patients with early spinal cord injury (SCI) via acoustic radiation force impulse (ARFI) imaging and to evaluate correlation between the SWV values and spasticity.MethodsEighteen patients with SCI within 3 months and 10 healthy adults participated. We applied the ARFI technique to measure SWV of gastrocnemius muscle (GCM) and long head of biceps femoris muscle. Spasticity of ankle and knee joint was assessed by original Ashworth Scale.ResultsTen patients with SCI had spasticity. Patients with spasticity had significantly faster SWV for GCM and biceps femoris muscle than those without spasticity (Mann-Whitney U test, p=0.007 and p=0.008) and normal control (p=0.011 and p=0.037, respectively). The SWV values of GCM correlated with the ankle spasticity (Spearman rank teat, p=0.026). There was significant correlation between the SWV values for long head of biceps femoris muscle and knee spasticity (Spearman rank teat, p=0.022).ConclusionARFI demonstrated a difference in muscle stiffness in the GCM between patients with spastic SCI and those without spasticity. This finding suggested that stiffness of muscles increased in spastic lower extremity of early SCI patients. ARFI imaging is a valuable tool for noninvasive assessment of the stiffness of the spastic muscle and has the potential to identify pathomechanical changes of the tissue associated with SCI.

Comparison of Rehabilitation Outcomes with Acoustic Radiation Force (ARFI) Elastosonography in Hemiplegic Patients Treated with Neuromuscular Electrical Stimulation

“…Also, Yaşar et al [24]. found high stiffness grades in spastic muscles in sonoelastographic parameters in their studies using MAS and [30]. When we compared the results of the study, our results were similar.…”

Reliability and quantification of gastrocnemius elasticity at relaxing and at submaximal contracted condition

“…In recent years, use of dynamic sonoelastography in the musculoskeletal area has been increased in research of muscle physiology [10][11][12][13] and in clinical conditions causing stiffness of muscles [14,15]. Elastography applications were developed to improve the diagnostic capability of traditional imaging techniques such as magnetic resonance imaging (MRI) and ultrasound by delineating the differential stiffness of healthy and unhealthy tissue [16].…”

Einfluss einer Kaltwasserimmersionstherapie auf die passive Muskelsteifigkeit

“…Eine standardisierte ARFI-Sequenz besteht aus einer schnellen Sequenz folgender Impulse: Zunächst werden Referenz-Pulse ausgesandt, um die ursprüngliche Beschaffenheit des Gewebes zu bestimmen. Anschließend wird der akustische Hochenergiepuls erzeugt, um eine lokal begrenzte Gewebedeformierung hervorzurufen, welche im letzten Schritt anhand bestimmter Tracking-Pulse dargestellt wird [54,57].…”

“…Yavuz et al [67] konnten unter diesem Aspekt Korrelationen zwischen der intramuskulären SWV und der aufgebrachten Kraft demonstrieren. Eine weitere Untersuchung in diesem Zusammenhang ergab eine signifikante Steigerung der Steifigkeit bei Kindern mit spastischer Zerebralparese oder spinalen Verletzungen im Vergleich zu gesunden Kindern [57,68]. Im Gegensatz dazu stehen die Ergebnisse einer weiteren Untersuchung, wobei die Muskelsteifigkeit der Wadenmuskulatur 60 Stunden nach einer induzierten ultrastrukturellen Muskelverletzung in Form einer DOMS signifikant abnahm [54].…”