Search results for "tendon"

Study of the Biceps Fatigue after Surgery on the Long Head of Biceps Tendon in Male Heavy Workers. A Prospective Randomized Clinical Trial Comparing …

2020

Triceps surae fascicle stretch is poorly correlated with short latency stretch reflex size

2015

Introduction: The short latency stretch reflex (SLR) is well described, but the stimulus that evokes the SLR remains elusive. One hypothesis states that reflex size is proportional to muscle fiber stretch, so this study examined the relationship between these 2 parameters in human triceps surae muscles. Methods: Achilles tendon taps and dorsiflexion stretches with different amplitudes and preactivation torques were applied to 6 participants while electromyography and muscle fascicle length changes were recorded in soleus and medial gastrocnemius (MG). Results: In response to tendon taps, neither fascicle length nor velocity changes were correlated with SLR size in either muscle, but acceler…

Individual muscle contributions to the in vivo achilles tendon force

1998

OBJECTIVE: To ascertain the possibility of non-uniform stress within the achilles tendon due to individual force contributions of the triceps surae. DESIGN: Calculation of non-uniform stress through discrepancies in moments about the ankle joint. BACKGROUND: Non-uniform stress over the cross-sectional area have been implied in the etiology of achilles tendon injury and may influence functional aspects. However, this has not been empirically demonstrated. METHODS: In vivo achilles tendon forces were measured with an optic fibre technique during isometric plantarflexions at systematically varied knee angles and contraction intensities. A comparison to the plantar force measured underneath the…

EFFECTS OF STRIKING STRATEGY ON LOWER EXTREMITY LOADING DURING RUNNING

2013

Backround It is expected that every second runner has a running-related overuse injury each year. The knee joint and Achilles tendon are the most commonly injured sites covering both about one fifth of all running related injuries. 1 Runners can be categorized into rearfoot strikers, mid-foot strikers or forefoot strikers based on the landing strategy at the instant of initial ground contact. Forefoot or mid-foot striking has been shown to reduce impact peak and loading rate of the ground reaction force during early stance phase. 2 Furthermore, the finding of the recent study suggest that forefoot striking may potentially decrease the risk of running-related injuries. 3 However, the effect …

Lower Limb Dominance, Morphology, and Sonographic Abnormalities of the Patellar Tendon in Elite Basketball Players: A Cross-Sectional Study.

2019

Context Patellar tendinopathy is common in basketball players, and structural ultrasound abnormalities can be found in symptomatic and asymptomatic tendons. Lower limb dominance may also be a critical load factor, potentially leading to overloading of the patellar tendon. Objective To describe and compare the prevalence by lower limb dominance of patellar tendons with structural and vascular abnormalities and to describe the morphologic measures of tendons without abnormalities among adult male elite basketball players. Design Cross-sectional study. Setting Medical center of a professional basketball team in the Spanish league. Patients or Other Participants A total of 73 adult male elite …

Surgical repair of acute Achilles tendon rupture with an end-to-end tendon suture and tendon flap.

2015

Abstract Background Achilles tendon ruptures are becoming more common. Complications after open or minimally invasive surgery are: recurrent rupture (2–8%), wound breakdown, deep infections, granuloma, and fistulas. The authors expose their experience with a personal technique. Materials In 8 patients with acute rupture of Achilles tendon the surgery was performed at least 25 days after trauma. Clinical exam and MR demonstrated in all case a total lesion of tendon. After a posterolateral skin incision the tendon stumps were debrided and suture in end-to-end fashion. A tendon flap was harvested from the proximal part of the tendon, in order to protect and reinforce the suture itself. A plast…

Micromechanical Properties and Collagen Composition of Ruptured Human Achilles Tendon

2012

Background:The Achilles tendon is one of the strongest tendons in the human body, and yet it frequently ruptures, which is a substantial clinical problem. However, the cause of ruptures remains elusive.Hypothesis:Ruptured human Achilles tendon displays inferior biomechanical properties and altered collagen composition compared with noninjured tendon.Study Design:Controlled laboratory study.Methods:Biopsy specimens were obtained at the rupture site and the noninjured part of the tendon (internal controls) in 17 patients with acute Achilles tendon rupture. Age- and weight-matched human cadaveric Achilles tendons (external controls) were also obtained. Tendon samples were tested micromechanica…

Reliability and methodology of quantitative assessment of harvested and unharvested patellar tendons of ACL injured athletes using ultrasound tissue …

2019

Ultrasound tissue characterization (UTC) imaging has been previously used to describe the characteristics of patellar and Achilles tendons. UTC imaging compares and correlates successive ultrasonographic transverse tendon images to calculate the distribution of four color-coded echo-types that represent different tendon tissue types. However, UTC has not been used to describe the characteristics of patellar tendons after anterior cruciate ligament reconstruction (ACLR). The aim of this cross-sectional study was to assess the intra and inter-rater reliability of the UTC in unharvested and harvested patellar tendons of patients undergoing ACLR. Intra and inter-rater reliability of both UTC da…

A Locked Intraosseous Nail for Transverse Patellar Fractures: A Biomechanical Comparison with Tension Band Wiring Through Cannulated Screws.

2018

Background Displaced transverse patellar fractures require open reduction and internal fixation. State-of-the-art stabilization techniques are tension band wiring (TBW) using Kirschner wires or cannulated screws. These techniques are associated with high rates of secondary fracture displacement, implant migration, implant prominence, wound-healing disturbances, and the need for implant removal. Recently, a locked intraosseous patellar nail prototype was developed. The aim of the present study was to investigate the biomechanical performance of this nail compared with TBW using cannulated screws. Methods Seven paired fresh-frozen human cadaveric knees were stripped of all soft tissues except…

Effects of muscle activation on shear between human soleus and gastrocnemius muscles

2015

Lateral connections between muscles provide pathways for myofascial force transmission. To elucidate whether these pathways have functional roles in vivo, we examined whether activation could alter the shear between the soleus (SOL) and lateral gastrocnemius (LG) muscles. We hypothesized that selective activation of LG would decrease the stretch-induced shear between LG and SOL. Eleven volunteers underwent a series of knee joint manipulations where plantar flexion force, LG, and SOL muscle fascicle lengths and relative displacement of aponeuroses between the muscles were obtained. Data during a passive full range of motion were recorded, followed by 20° knee extension stretches in both pass…