In vitro fatigue of human tendons

Schechtman, Helio; Bader, Dan L.

doi:10.1016/s0021-9290(97)00033-x

Cited by 188 publications

(141 citation statements)

References 22 publications

Supporting

Mentioning

133

Contrasting

Unclassified

Order By: Relevance

“…As a highstressed tendon, AT might be more fatigue resistant than a number of other tendons in the human body. Although results agree with many previous in vitro studies Schechtman and Bader, 1997;Wang et al, 1995b,) they disagree with the one and only study conducted with human ATs (Wren et al, 2003). It is possible that clamping problems, often associated to in vitro experiments, could cause premature failure and thus different conclusions about tendon fatigue resistance between in vitro and in vivo.…”

Section: Discussionsupporting

confidence: 51%

“…Also, they are the only ones to report induced rupture for human AT. Cycle times to rupture at comparable stress levels were much higher in tendons of sheep and wallaby (Wang et al, 1995b), and also in human EDL tendons (Schechtman and Bader, 1997). The reason for different results could be methodological and due to difficulties in clamping techniques .…”

Section: Discussionmentioning

confidence: 99%

“…When rupture occurs after static loading, it is referred to as a creep rupture, and when it occurs after cyclic loading, it is known as a fatigue rupture. Creep or fatigue ruptures have been demonstrated in wallaby tendons (Wang and Ker, 1995a;Wang et al, 1995b;Ker et al, 2000) and in sheep tendons , fatigue ruptures in human extensor digitorum longus (EDL) tendons (Schechtman and Bader, 1994;Schechtman and Bader, 1997;Schechtman and Bader, 2002), and creep and fatigue ruptures in human Achilles tendons (AT) (Wren et al, 2003). However, ultimate stress is not a valid parameter to describe tendon fatigue in living tissue.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

In vivo mechanical response of human Achilles tendon to a single bout of hopping exercise

Peltonen

Cronin

Avela

et al. 2010

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARYStiffness of the human Achilles tendon (AT) was determined in vivo before and after a single bout of hopping exercise. It was hypothesized, based on published data using in vitro specimens, that a reduction in AT stiffness may occur after just 1000 loading cycles at physiological stress levels. Ten healthy subjects performed two-legged hopping exercise consisting of 1150-2600 high impacts. Tendon stiffness was determined in several isometric ramp contractions [20%, 40%, 60%, 80% and 100% maximum voluntary contraction (MVC)] during which tendon elongation was measured using ultrasonography and two cameras. Tendon force was calculated by dividing measured ankle torque by magnetic resonance imaging-derived AT lever arm length. Tendon stiffness remained unchanged, being 430±200Nmm -1 before and 390±190Nmm -1 after the exercise [not significant (n.s.)]. Despite the lack of changes in stiffness, maximum tendon force during MVC was reduced from 3.5±0.6kN to 2.8±0.7kN (P<0.01). As the proposed decline in stiffness was not observed, it is concluded that mechanical fatigue did not take place in the AT of healthy individuals after a single bout of high-impact exercise performed until exhaustion.

show abstract

Section: Discussionsupporting

confidence: 51%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

In vivo mechanical response of human Achilles tendon to a single bout of hopping exercise

Peltonen

Cronin

Avela

et al. 2010

Journal of Experimental Biology

View full text Add to dashboard Cite

show abstract

“…Exercise may have induced an increased capacity of tenocytes to repair microdamage, but no analysis was performed on the metabolic activity of the cells within the tendon in this study. In addition, fatigue resistance is a difficult characteristic to measure objectively with biological relevance, although some attempts have been made in other species (31,47,63).…”

Section: Discussionmentioning

confidence: 99%

Can exercise modulate the maturation of functionally different immature tendons in the horse?

Kasashima

Takahashi²,

Birch³

et al. 2008

Journal of Applied Physiology

View full text Add to dashboard Cite

Tendons can be considered in two functional groups, those contributing to energetics of locomotion and those acting solely to position the limb. The energy-storing tendons in both human and equine athletes have a high frequency of injury with similar pathophysiology. In previous studies, high-intensity exercise appears to induce a disruption of the matrix rather than functional adaptation in adults. Here we explore the hypothesis that the introduction of controlled exercise during growth would result in an adaptive response without deleterious effects. Young horses were given a controlled exercise program similar to that previously shown to induce matrix changes in energy-storing tendons of skeletally mature animals. The tendons were assessed in relation to mechanical properties, molecular composition, and morphology. Results showed a significant increase in cartilage oligomeric matrix protein (COMP) in the positional tendon but not in the energy-storing tendon. Other matrix properties and mechanical properties were not significantly changed. While the imposition of high-strain-rate exercise in immature horses failed to augment the development of the energy-storing tendon over and above that induced by normal pasture exercise, it did not induce deleterious changes, supporting an earlier introduction of athletic training in horses.adaptation; hypertrophy; cartilage oligomeric matrix protein; biomechanics TENDON OVERUSE INJURIES are not only responsible for considerable loss of athletic potential in both horses (30,35,58) and humans (64), but their prevalence appears to be increasing, with a doubling in Achilles tendinopathy in recent years (26,27,34,37,38). While tendons that link muscle to bone can act merely as force transmitters to position limbs, a specific subgroup of tendons whose function is to store elastic energy contributes to efficient locomotion by acting as springs, while the associated muscle fibers serve primarily to dampen vibrations (1, 59). The Thoroughbred racehorse is a prime example of an elite animal athlete both in terms of evolution and subsequent genetic selection and conditioning. The superficial digital flexor tendon (SDFT) in the horse is an energy-storing tendon with functional and compositional similarities to the Achilles tendon in humans (7). This tendon is highly susceptible to injury, accounting for 93% of all tendon and ligament injuries in a study by Ely et al. (15) and thus can be used as a "natural" model to study tendon development and degeneration (51). The common digital extensor tendon (CDET) in contrast is a good example of a positional tendon analogous to the anterior tibialis in the human (3, 62).Over the last two decades there has been a great increase in the scientific understanding of the response of bone and muscle to mechanical loading. The mechanobiology of tendon, however, is less well understood. Effects of exercise on tendon properties have been studied in various species, including mouse (36), rat (49, 55), rabbit (61), chicken (2), guinea fowl (8), miniatur...

show abstract

“…For example, the sub-process MD has been investigated through mechanical fatigue testing. [2][3][4][5][6][7][8] We have learned from these studies mainly that under stress-controlled fatigue-loading: tendon strain increases continuously in a triphasic pattern 2,7,8 ; tissue stiffness changes in an ''inverse U'' pattern 2 ; time to rupture decreases as the load increases 3,5,7,8 ; and tendon diameter increases with damage. 4 However, the active component of tendon response (the tissue cells) was not examined in these studies.…”

mentioning

confidence: 99%

Relative contributions of mechanical degradation, enzymatic degradation, and repair of the extracellular matrix on the response of tendons when subjected to under‐ and over‐ mechanical stimulations in vitro

Cousineau-Pelletier

Langelier

2009

Journal Orthopaedic Research

View full text Add to dashboard Cite

Tendon response to mechanical loading results in either homeostasis, improvement, or degeneration of tissue condition. In an effort to better understand the development of tendinopathies, this study investigated the mechanical and structural responses of tendons subjected to under-and over-stimulations (1.2% and 1.8% strain respectively, 1 Hz). The objective was to examine three sub-processes of tendon response: mechanical degradation, enzymatic degradation, and repair of the extracellular matrix. We subjected rat tail tendons to a 10-day stimulation protocol with four periods of 6 h each day: 30 min of stimulation and 5 h 30 min of rest. To investigate the contribution of the three sub-processes, we controlled the contribution of the cells through variations in the nutrient and protease inhibitor content in the in vitro solutions. Using nondestructive cyclic tests, we evaluated the daily changes in the peak stress. To assess structural changes, we carried out microscopic analyses at the end of the study period. We observed that the relative contributions of the sub-processes differed according to the stimulation amplitude. With over-stimulation of tendons immersed in DMEM, we succeeded in reducing enzymatic degradation and increasing peak stress. In under-stimulation, the addition of protease inhibitors was required to obtain the same result. ß

show abstract

In vitro fatigue of human tendons

Cited by 188 publications

References 22 publications

In vivo mechanical response of human Achilles tendon to a single bout of hopping exercise

In vivo mechanical response of human Achilles tendon to a single bout of hopping exercise

Can exercise modulate the maturation of functionally different immature tendons in the horse?

Relative contributions of mechanical degradation, enzymatic degradation, and repair of the extracellular matrix on the response of tendons when subjected to under‐ and over‐ mechanical stimulations in vitro

Contact Info

Product

Resources

About