Search results for "tendon"
showing 10 items of 240 documents
Afferent contribution to locomotor muscle activity during unconstrained overground human walking:an analysis of triceps surae muscle fascicles
2010
Plantar flexor series elasticity can be used to dissociate muscle–fascicle and muscle–tendon behavior and thus afferent feedback during human walking. We used electromyography (EMG) and high-speed ultrasonography concomitantly to monitor muscle activity and muscle fascicle behavior in 19 healthy volunteers as they walked across a platform. On random trials, the platform was dropped (8 cm, 0.9 g acceleration) or held at a small inclination (up to ±3° in the parasagittal plane) with respect to level ground. Dropping the platform in the mid and late phases of stance produced a depression in the soleus muscle activity with an onset latency of about 50 ms. The reduction in ground reaction force…
Reverse Homodigital Dorsal Radial Flap of the Thumb.
2006
BACKGROUND: Reconstruction of extensive distal defects of the thumb with exposure of bone, tendon, or joint can be a difficult problem because immediate closure is of paramount importance for preserving function and avoiding complications. Surgical treatment includes the use of local, reverse flow, and free flaps. The authors describe a new reverse homodigital flap to repair distal defects of the thumb. This flap is raised from the dorsal radial side of the first metacarpal area. It is pedicled on the dorsal radial collateral artery, which is constant for course, caliber, and communication with the palmar circuit. METHODS: The flap is raised by means of distal to proximal dissection, the sk…
Fibroadipose Vascular Anomaly of the Upper Extremity
2021
ABSTRACT Alomari and colleagues described in 2014 for the first time a distinct combination of vascular malformation, fibrofatty muscular infiltration and contracture which was termed fibroadipose vascular anomaly (FAVA) (J Pediatr Orthoped 34, 109-117 (2014). So far only few publications (J Pediatr Orthoped (2014) 34, 109-117; J Hand Surg (2020). 45, 68.e1, 68.e13; Ann Vasc Dis (2014) 7, 316-319; Pediatr Radiol 46, 1179-1186 (2016)) concerning this newly described disease have been published, covering only a limited number of cases. We present a case of a 19-year-old male patient suffering from a FAVA of the proximal forearm with a severe contracture of the infiltrated flexor musculature. …
Elderly adults delay proprioceptive reweighting during the anticipation of collision avoidance when standing.
2012
The ability to reweight visual and proprioceptive information is critical for maintaining postural stability in a dynamic environment. In this study, we examined whether visual anticipation of collision avoidance (AV) while standing could facilitate the down-weighting of altered proprioception in young and elderly adults. Twelve young (24.91 ± 6.44 years) and 12 elderly (74.8 ± 6.42 years) participants stood upright for 180 s under two task conditions: (a) quiet stance (QS) and (b) standing while anticipating virtual objects to be avoided. In order to disrupt the accuracy of proprioceptive input participants were exposed to bilateral Achilles tendon vibration during the middle 60 s of stand…
Individual Region- and Muscle-specific Hamstring Activity at Different Running Speeds
2019
Introduction \ud Hamstring strain injuries typically occur in the proximal biceps femoris long head (BFlh) at high running speeds. Strain magnitude seems to be the primary determinant of strain injury, and may be regulated by muscle activation. In running, BFlh strain is largest in the proximal region, especially at high speeds. However, region-specific activity has not been examined. This study examined the proximal–distal and intermuscular activity of BFlh and semitendinosus (ST) as a function of increasing running speed.\ud \ud Methods \ud Thirteen participants ran at steady speeds of 4.1 (slow), 5.4 (moderate), and 6.8 m·s−1 (fast) on a treadmill. Region- and muscle-specific EMG activit…
Treatment of acute Achilles tendon ruptures with Achillon device: Clinical outcomes and kinetic gait analysis
2009
Abstract Background We reviewed the outcomes of the Achillon minimally invasive suture system and an early semi-functional rehabilitation program for the treatment of acute Achilles tendon ruptures. Methods From December 2006 to April 2008, 18 consecutive patients with acute Achilles tendon ruptures were retrospectively reviewed with an average follow-up of 22 months. Clinical data were assessed with the patient satisfaction and the AOFAS hindfoot score. Biomechanical gait parameters were obtained using the NedAMH/IBV dynamometric platform. Results At last follow-up the AOFAS score was 98 (range, 89–100) and correlated well with kinetic gait analysis. All patients regained normal range of m…
Shock wave therapy versus conventional surgery in the treatment of calcifying tendinitis of the shoulder.
2001
A prospective quasirandomized study was performed to compare the effects of surgical extirpation (Group I, 29 patients) with the outcome after high-energy extracorporeal shock wave therapy (Group II, 50 patients; 3,000 impulses of an energy flux density of 0.6 mJ/mm2) in patients with a chronic calcifying tendinitis in the supraspinatus tendon. Symptoms and demographic data of the two groups were comparable. According to the University of California Los Angeles Rating System, the mean score in Group I was 30 points with 75% good or excellent results after 12 months, and 32 points with 90% good or excellent results after 24 months. Radiologically, there was no calcific deposit in 85% of the …
Biomechanical Loading of Achilles Tendon During Normal Locomotion
1992
Direct in vivo Achilles tendon force measurements open up new possibilities for understanding the loading of the Achilles tendon during natural locomotion. This article describes how these human experiments can be performed. The results of these experiments imply that Achilles tendon forces are unexpectedly high in certain activities (e.g., hopping) and that the rates of loading rather than the absolute magnitudes of the recorded forces may be more relevant for clinical purposes as well as for the construction of artificial tendon materials.
Age-related differences in Achilles tendon properties and triceps surae muscle architecture in vivo
2012
This study examined the concurrent age-related differences in muscle and tendon structure and properties. Achilles tendon morphology and mechanical properties and triceps surae muscle architecture were measured from 100 subjects [33 young (24 ± 2 yr) and 67 old (75 ± 3 yr)]. Motion analysis-assisted ultrasonography was used to determine tendon stiffness, Young's modulus, and hysteresis during isometric ramp contractions. Ultrasonography was used to measure muscle architectural features and size and tendon cross-sectional area. Older participants had 17% lower ( P < 0.01) Achilles tendon stiffness and 32% lower ( P < 0.001) Young's modulus than young participants. Tendon cross-section…
In vivo muscle mechanics during locomotion depend on movement amplitude and contraction intensity
2001
The effects of movement amplitude and contraction intensity on triceps surae and quadriceps femoris muscle function were studied during repetitive hopping. In vivo forces from Achilles and patellar tendons were recorded with the optic fibre technique from eight volunteers. The performances were filmed (200 Hz) to determine changes in muscle-tendon unit length and velocity. When hopping with a small amplitude (23 degrees knee flexion during the ground contact phase), the Achilles tendon was primarily loaded whereas patellar tendon forces were greater in large-amplitude hopping (56 degrees knee flexion). In spite of the different magnitudes of stretch in the quadriceps femoris muscle, the str…