OBJECTIVE: To investigate the mechanisms of contracture after stroke by comparing passive mechanical properties of gastrocnemius muscle-tendon units, muscle fascicles, and tendons in people with ankle contracture after stroke with control participants. DESIGN: Cross-sectional study. SETTING: Laboratory in a research institution. PARTICIPANTS: A convenience sample of people with ankle contracture after stroke (n=20) and able-bodied control subjects (n=30). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Stiffness and lengths of gastrocnemius muscle-tendon units, lengths of muscle fascicles, and tendons at specific tensions. RESULTS: At a tension of 100N, the gastrocnemius muscle-tendon unit was significantly shorter in participants with stroke (mean, 436mm) than in able-bodied control participants (mean, 444mm; difference, 8mm; 95% confidence interval [CI], 0.2-15mm; P=.04). Muscle fascicles were also shorter in the stroke group (mean, 44mm) than in the control group (mean, 50mm; difference, 6mm; 95% CI, 1-12mm; P=.03). There were no significant differences between groups in the mean stiffness or length of the muscle-tendon units and fascicles at low tension, or in the mean length of the tendons at any tension. CONCLUSIONS: People with ankle contracture after stroke have shorter gastrocnemius muscle-tendon units and muscle fascicles than control participants at high tension. This difference is not apparent at low tension.
OBJECTIVE: To investigate the mechanisms of contracture after stroke by comparing passive mechanical properties of gastrocnemius muscle-tendon units, muscle fascicles, and tendons in people with ankle contracture after stroke with control participants. DESIGN: Cross-sectional study. SETTING: Laboratory in a research institution. PARTICIPANTS: A convenience sample of people with ankle contracture after stroke (n=20) and able-bodied control subjects (n=30). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Stiffness and lengths of gastrocnemius muscle-tendon units, lengths of muscle fascicles, and tendons at specific tensions. RESULTS: At a tension of 100N, the gastrocnemius muscle-tendon unit was significantly shorter in participants with stroke (mean, 436mm) than in able-bodied control participants (mean, 444mm; difference, 8mm; 95% confidence interval [CI], 0.2-15mm; P=.04). Muscle fascicles were also shorter in the stroke group (mean, 44mm) than in the control group (mean, 50mm; difference, 6mm; 95% CI, 1-12mm; P=.03). There were no significant differences between groups in the mean stiffness or length of the muscle-tendon units and fascicles at low tension, or in the mean length of the tendons at any tension. CONCLUSIONS:People with ankle contracture after stroke have shorter gastrocnemius muscle-tendon units and muscle fascicles than control participants at high tension. This difference is not apparent at low tension.
Authors: Mao Li; Karol Miller; Grand Roman Joldes; Barry Doyle; Revanth Reddy Garlapati; Ron Kikinis; Adam Wittek Journal: Med Image Anal Date: 2015-01-30 Impact factor: 8.545
Authors: Peter W Stubbs; Lee D Walsh; Arkiev D'Souza; Martin E Héroux; Bart Bolsterlee; Simon C Gandevia; Robert D Herbert Journal: J Physiol Date: 2018-04-25 Impact factor: 5.182
Authors: Richard L Lieber; Thomas J Roberts; Silvia S Blemker; Sabrina S M Lee; Walter Herzog Journal: J Neuroeng Rehabil Date: 2017-10-23 Impact factor: 4.262
Authors: Vanessa Ade; Dale Schalkwijk; Michael Psarakis; Michael D Laporte; Timothy J Faras; Remi Sandoval; Fadi Najjar; Peter W Stubbs Journal: PLoS One Date: 2018-07-12 Impact factor: 3.240