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James R. Debenham, William I. Gibson, Mervyn J. Travers, Amity C. Campbell and Garry T. Allison

Context:

Eccentric exercises are increasingly being used to treat lower-limb musculoskeletal conditions such as Achilles tendinopathy. Despite widespread clinical application and documented efficacy, mechanisms underpinning clinical benefit remain unclear. Positive adaptations in motor performance are a potential mechanism.

Objective:

To investigate how an eccentric loading intervention influences measures of stretch-shortening-cycle (SSC) behavior during a hopping task.

Design:

Within-subjects repeated-measures observational study.

Setting:

University motion-analysis laboratory.

Participants:

Healthy adults.

Interventions:

A single intervention of 5 sets of 10 eccentric plantar-flexion contractions at 6 repetitions maximum using a commercial seated calf-raise machine.

Main Outcome Measures:

Lower-limb stiffness, sagittal-plane ankle kinematics, and temporal muscle activity of the agonist (soleus) and antagonist (tibialis anterior) muscles, measured during submaximal hopping on a custom-built sledge-jump system.

Results:

Eccentric loading altered ankle kinematics during submaximal hopping; peak angle shifted to a less dorsiflexed position by 2.9° and ankle angle precontact shifted by 4.4° (P < .001). Lower-limb stiffness increased from 5.9 to 6.8 N/m (P < .001), while surface EMG measures of soleus occurred 14–44% earlier (P < .001) after the loading intervention.

Conclusions:

These findings suggest that eccentric loading alters SSC behavior in a manner reflective of improved motor performance. Decreased ankle excursion, increased lower-limb stiffness, and alterations in motor control may represent a positive adaptive response to eccentric loading. These findings support the theory that mechanisms underpinning eccentric loading for tendinopathy may in part be due to improved “buffering” of the tendon by the neuromuscular system.

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Zong-Ming Li, Shouchen Dun, Daniel A. Harkness and Teresa L. Brininger

The purpose of the current study was to examine motion enslaving characteristics of multiple fingers during isolated flexion of the distal interphalangeal joints. Because the distal interphalangeal joints are flexed by multiple tendons of the single flexor digitorum profundus, the current experimental design provided a unique advantage to understand inter-finger enslaving effects due to the flexor digitorum profundus. Eight subjects were instructed to flex the distal inter-phalangeal joint of each individual finger from the fully extended position to the fully flexed position as quickly as possible. Maximal angular displacements, velocities, or accelerations of individual fingers were used to calculate the enslaving effects. An independence index, defined as the ratio of the maximal displacement of a master finger to the sum of the maximal displacements of the master and slave fingers, was used to quantify relative independence of each finger. The angular displacements of the index, middle, ring, and little fingers were 68.6° (±7.7), 68.1° (±10.1), 68.1° (±9.7), and 74.7° (±13.3), respectively. The motion of a master finger was invariably accompanied by motion of 1 or 2 slave fingers. Angular displacements of master and slave fingers increased to maximum values with time monotonically. Velocity curves demonstrated bell-shaped profile, and the acceleration curves were sinusoidal. Enslaving effects were generated mainly on the neighboring fingers. The amount of enslaving on the middle and ring fingers exceeded more than 60% of their own maximum angular displacements when a single adjacent finger moved. The index finger had the highest level of independence as indicated by the lowest enslaving effects on other fingers or by other fingers. The independence indices of the index, middle, ring, and little fingers were 0.812 (±0.070), 0.530 (±0.051), 0.479 (±0.099), and 0.606 (±0.148), respectively. In all tasks, motion of slave fingers always lagged with respect to the master finger. Time delays, on average, ranged from 7.8 (±5.0) to 35.9 (±22.1) ms. Our results suggest that there exist relatively large enslaving effects among the compartments of the flexor digitorum profundus, and functional independence of fingers in daily activities is likely enhanced through synergistic activities of multiple muscles, including flexors and extensors.

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. previous knee surgery 10. In this case, the three patients were treated with PRT at these two sites: a. patella tendon and psoas muscle b. patella tendon and quadriceps muscle c. patella tendon and quadriceps tendon d. psoas muscle and quadriceps tendon 11. Discharge criteria for these patients included

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Lucas C. Bianco, James M. May, Smokey L. Fermin, Robert Oates and Scott W. Cheatham

patient outcomes related to function and pain. Persistent pain in the anterior aspect of the knee is commonly associated with patella tendinopathy. 1 – 3 Patella tendinopathy includes conditions involving the patella tendon on the inferior pole of the patella and is commonly associated with inflammation

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Jan Wilke, Kristin Kalo, Daniel Niederer, Lutz Vogt and Winfried Banzer

Kim et al 8 , 9 observed that the plantar aponeurosis and the Achilles tendon merge strongly in younger persons, while the degree of morphological continuity ceases or even completely disappears in older persons. If, thus, a mechanical force transmission represents the decisive factor of nonlocal

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Paula Chaves, Daniela Simões, Maria Paço, Sandra Silva, Francisco Pinho, José Alberto Duarte and Fernando Ribeiro

Patellar tendinopathy, also known as jumper’s knee, is a condition associated with load demands and excessive use of the patellar tendon, which results in a pathologic cascade of events including neovascularization, nerve ingrowth, tendon degeneration, and, ultimately, a painful tendon. 1 – 3

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Yuya Ueda, Takehiko Matsushita, Yohei Shibata, Kohei Takiguchi, Akihiro Kida, Daisuke Araki, Noriyuki Kanzaki, Yuichi Hoshino, Rei Ono, Yoshitada Sakai and Ryosuke Kuroda

remain unclear. Eitzen et al 15 found that at least 80% preoperative quadriceps strength was necessary to achieve a good postoperative quadriceps strength recovery and self-reported function at 2 years after ACL reconstruction with bone–patellar tendon–bone (BPTB) autograft. Ueda et al 16 have reported

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Gulcan Harput, Volga B. Tunay and Matthew P. Ithurburn

and physical therapy at our clinic. Inclusion criteria for the study included (1) unilateral arthroscopic ACLR with hamstring tendon or bone–patellar–tendon–bone grafts, (2) age between 16 and 35 years, (3) noncontact injury mechanism, (4) preinjury Tegner score ≥5, and (5) regularly continued the

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Hio Teng Leong and Siu Ngor Fu

partial or complete tears that is related to RC tendons and associated tissues such as long head of the biceps tendinopathy, subacromial bursitis, and shoulder impingement syndrome. 2 Clinical symptoms include pain, weakness, and disability during arm elevation, and affects health and quality of life by

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Niranjan Chakrabhavi and Varadhan SKM

effect of finger interdependence is primarily associated with mechanical and neural mechanisms related to the extrinsic muscles that are responsible for movement of finger phalanges: (1) mechanical coupling—the tendons connecting extrinsic muscle to neighboring fingers of the hand, mechanically shear