Impact of seated and standing positions on triceps surae muscle activation in unilateral Achilles tendon rupture

Ankle joint quasi-stiffness is an aggregate measure of the interaction between triceps surae muscle stiffness and Achilles tendon stiffness. This interaction may be altered due to age-related changes in the structural properties and functional behavior of the Achilles tendon and triceps surae muscles. The authors hypothesized that, due to a more compliant of Achilles’ tendon, older adults would exhibit lower ankle joint quasi-stiffness than young adults during walking and during isolated contractions at matched triceps surae muscle activations. The authors also hypothesized that, independent of age, triceps surae muscle stiffness and ankle joint quasi-stiffness would increase with triceps surae muscle activation. The authors used conventional gait analysis in one experiment and, in another, electromyographic biofeedback and in vivo ultrasound imaging applied during isolated contractions. The authors found no difference in ankle joint quasi-stiffness between young and older adults during walking. Conversely, this study found that (1) young and older adults modulated ankle joint quasi-stiffness via activation-dependent changes in triceps surae muscle length–tension behavior and (2) at matched activation, older adults exhibited lower ankle joint quasi-stiffness than young adults. Despite age-related reductions during isolated contractions, ankle joint quasi-stiffness was maintained in older adults during walking, which may be governed via activation-mediated increases in muscle stiffness.

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Compensatory muscle activation caused by tendon lengthening post-Achilles tendon rupture

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-013-2512-1 ◽

2013 ◽

Vol 23 (3) ◽

pp. 868-874 ◽

Cited By ~ 45

Author(s):

Stephen M. Suydam ◽

Thomas S. Buchanan ◽

Kurt Manal ◽

Karin Gravare Silbernagel

Keyword(s):

Achilles Tendon ◽

Muscle Activation ◽

Tendon Rupture ◽

Achilles Tendon Rupture ◽

Tendon Lengthening

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Neuromechanical activation of triceps surae muscle remains altered at 3.5 years following open surgical repair of acute Achilles tendon rupture

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-021-06512-z ◽

2021 ◽

Author(s):

Markus Wenning ◽

Marlene Mauch ◽

Albrecht Heitner ◽

Johannes Lienhard ◽

Ramona Ritzmann ◽

...

Keyword(s):

Achilles Tendon ◽

Gait Analysis ◽

Tendon Rupture ◽

Surgical Repair ◽

Achilles Tendon Rupture ◽

Triceps Surae ◽

Median Frequency ◽

Open Surgical Repair ◽

Neuromuscular Activation ◽

Injured Side

Abstract Purpose To assess whether the neuromuscular activation pattern following Achilles tendon rupture and repair may contributes to the observable functional deficits in this severe and increasingly frequent injury. Methods In this study, the neuromuscular activation using surface EMG of n = 52 patients was assessed during a battery of functional performance tasks to assess potential alterations of muscular activation and recruitment. We analyzed the injured leg vs. the contralateral healthy leg at a mean of 3.5 years following open surgical repair. The testing battery included isokinetic strength testing, bipedal and single-legged heel-rise testing as well as gait analysis. Results During isokinetic testing, we observed a higher activation integral for all triceps surae muscles of the injured side during active dorsiflexion, e.g., eccentric loading on the injured leg, while concentric plantarflexion showed no significant difference. Dynamic heel-rise testing showed a higher activation in concentric and eccentric loading for all posterior muscles on the injured side (not significant); while static heel-rise for 10 sec. revealed a significantly higher activation. Further analysis of frequency of fast Fourier-transformed EMG revealed a significantly higher median frequency in the injured leg. Gait analysis revealed a higher pre-activation of the tibialis anterior before ground contact, while medial and lateral gastrocnemius muscles of the injured leg showed a significantly higher activation during push-off phase. Conclusions The results of this study provide evidence on the neuromuscular changes 3.5 years following open surgical Achilles tendon repair. These complex neuromuscular changes are manifested to produce the maximum force output whilst protecting the previously injured tendon. The observed alterations may be related to an increased recruitment of type II muscle fibers which could make the muscles prone to fatigue. Level of evidence III.

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The effects of triceps surae muscle stimulation on localized achilles subtendon tissue displacements

Journal of Experimental Biology ◽

10.1242/jeb.242135 ◽

2021 ◽

Author(s):

Nathan L. Lehr ◽

William H. Clark ◽

Michael D. Lewek ◽

Jason R. Franz

Keyword(s):

Achilles Tendon ◽

Muscle Activation ◽

Triceps Surae ◽

Medial Gastrocnemius ◽

Muscle Stimulation ◽

Triceps Surae Muscle ◽

Ankle Angle ◽

In Series ◽

Fixed End

The triceps surae muscle tendon unit is comprised of the lateral and medial gastrocnemius (MG) and soleus (SOL) muscles and three in series elastic “subtendons” that form the Achilles tendon. Comparative literature and our own in vivo evidence suggests that sliding between adjacent subtendons may facilitate independent muscle actuation. We aim to more clearly define the relation between individual muscle activation and subtendon tissue displacements. Here, during fixed-end contractions, electrical muscle stimulation controlled the magnitude of force transmitted via individual triceps surae muscles while ultrasound imaging recorded resultant subtendon tissue displacements. We hypothesized that MG and SOL stimulation would elicit larger displacements in their associated subtendon. 10 young adults completed 4 experimental activations at 3 ankle angles (-20°, 0°, 20°) with knee flexed to approximately 20°: MG stimulation (STIMMG), SOL stimulation (STIMSOL), combined stimulation, and volitional contraction. At 20° plantarflexion, STIMSOL elicited 49% larger tendon non-uniformity (SOL – MG subtendon tissue displacement) than that of STIMMG (p=0.004). For STIMSOL, a one-way post-hoc ANOVA revealed a significant main effect of ankle angle (p=0.009) on Achilles tendon non-uniformity. However, peak tendon non-uniformity decreased by an average of 61% from plantarflexion to dorsiflexion, likely due to an increase in passive tension. Our results suggest that localized tissue displacements within the Achilles tendon respond in anatomically consistent ways to differential patterns of triceps surae muscle activation, but these relations are highly susceptible to ankle angle. This in vivo evidence points to at least some mechanical independence in actuation between the human triceps surae muscle-subtendon units.

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TL 18161 - Evaluation of Achilles tendon oxygen saturation in patients with tendon rupture

Scientific Journal of the Foot & Ankle ◽

10.30795/scijfootankle.2019.v13.1074 ◽

2019 ◽

Vol 13 (Supl 1) ◽

pp. 95S

Author(s):

Márcio De Faria Freitas ◽

Mauro César Matos e Dinato ◽

Miguel Viana Pereira Filho ◽

Tatiana Ferreira dos Santos ◽

Raul Dias dos Santos Filho ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Oxygen Saturation ◽

Achilles Tendon ◽

Near Infrared ◽

Tendon Rupture ◽

Achilles Tendon Rupture ◽

Triceps Surae ◽

Control Group ◽

History Of ◽

And Control

Introduction: Histopathological analyses of ruptured tendons show hypoxia-related tissue degeneration. Intrinsic factors that may cause tissue hypoxia, especially during physical exercise, may be related to Achilles tendon ruptures. Thus, the objective of the present study is to compare the resting oximetry of patients who had a ruptured Achilles tendon with that of a control group after exercise and after muscle ischemia. Methods: This was a single-center, comparative, cross-sectional observational study approved by the research ethics committee. The study assessed the Achilles tendon oxygen saturation of 2 groups: patients with a history of total Achilles tendon rupture (R: n=12) and control individuals without a history of tendon rupture (C: n=11). Oxygen saturation was measured by infrared spectroscopy on a near-infrared spectroscopy (NIRS) device (PortaMon, Artinis Medical Systems). Data were collected after the patient had rested at least 10 minutes in the supine position at the following times: test, after controlled contractions of the triceps surae muscle, and after 5 minutes of leg ischemia. The NIRS sensor was placed on the contralateral Achilles tendon in group R or on a randomized limb in group C. Data normality was confirmed using the Shapiro-Wilk test, and the groups were compared using the independent samples t test, with a significance level of p<0.05. Results: The oximetry levels of group R were similar to those of group C at rest (R: 72 ± 9% vs. C: 74 ± 6%, P=0.598), after exercise (R: 74 ± 5% vs. C: 77 ± 4%, p=0.199), and after 5 minutes of ischemia (R: 79 ± 3% vs. C: 80 ± 5, p=0.856). Conclusion: No differences in Achilles tendon oxygen saturation were identified between individuals with a history of rupture and control individuals

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Muscle Activation of the Uninjured Leg During an Acute Achilles Tendon Rupture

The Journal of Strength and Conditioning Research ◽

10.1519/jsc.0b013e3181e3120f ◽

2010 ◽

Vol 24 (8) ◽

pp. 2085-2087

Author(s):

Gretchen D Oliver ◽

Christopher P Dougherty

Keyword(s):

Achilles Tendon ◽

Muscle Activation ◽

Tendon Rupture ◽

Achilles Tendon Rupture

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Muscle Activation Of The Contralateral Leg During An Acute Achilles Tendon Rupture

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000355296.49902.84 ◽

2009 ◽

Vol 41 ◽

pp. 243

Author(s):

Gretchen D. Oliver ◽

Christopher P. Dougherty

Keyword(s):

Achilles Tendon ◽

Muscle Activation ◽

Tendon Rupture ◽

Achilles Tendon Rupture

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Functional Ankle Range of Motion but Not Peak Achilles Tendon Force Diminished With Heel-Rise and Jumping Tasks After Achilles Tendon Repair

The American Journal of Sports Medicine ◽

10.1177/03635465211019436 ◽

2021 ◽

pp. 036354652110194

Author(s):

Jennifer A. Zellers ◽

Josh R. Baxter ◽

Karin Grävare Silbernagel

Keyword(s):

Achilles Tendon ◽

Range Of Motion ◽

Tendon Rupture ◽

Achilles Tendon Rupture ◽

Tendon Repair ◽

Mean Difference ◽

Triceps Surae ◽

Plantar Flexor ◽

Achilles Tendon Repair ◽

Ankle Function

Background: Deficits in sporting performance after Achilles tendon repair may be due to changes in musculotendinous unit structure, including tendon elongation and muscle fascicle shortening. Purpose/Hypothesis: The purpose was to discern whether Achilles tendon rupture reduces triceps surae muscle force generation, alters functional ankle range of motion, or both during sports-related tasks. We hypothesized that individuals who have undergone Achilles tendon repair lack the functional ankle range of motion needed to complete sports-related tasks. Study Design: Descriptive laboratory study. Methods: The study included individuals 1 to 3 years after treatment of Achilles tendon rupture with open repair. Participants (n = 11) completed a heel-rise task and 3 jumping tasks. Lower extremity biomechanics were analyzed using motion capture. Between-limb differences were tested using paired t test. Results: Pelvic vertical displacement was reduced during the heel-rise (mean difference, −12.8%; P = .026) but not during the jumping task ( P > .1). In the concentric phase of all tasks, peak ankle plantarflexion angle (range of mean difference, −19.2% to −48.8%; P < .05) and total plantar flexor work (defined as the area under the plantar flexor torque – ankle angle curve) (range of mean difference, −9.5% to −25.7%; P < .05) were lower on the repaired side relative to the uninjured side. No significant differences were seen in peak Achilles tendon load or impulse with any of the tasks. There were no differences in plantar flexor work or Achilles tendon load parameters during eccentric phases. Conclusion: Impaired task performance or increased demands on proximal joints were observed on the repaired side in tasks isolating ankle function. Tasks that did not isolate ankle function appeared to be well recovered, although functional ankle range of motion was reduced with rupture. Reduced plantar flexor muscle-tendon unit work supports previous reports that an elongated tendon and shorter muscle fascicles caused by Achilles tendon rupture constrain functional capacity. Achilles tendon peak load and impulse were not decreased, suggesting that reduced and shifted functional ankle range of motion (favoring dorsiflexion) underlies performance deficits. Clinical Relevance: These findings point to the need to reduce tendon elongation and restore muscle length of the triceps surae after Achilles tendon rupture in order to address musculature that is short but not necessarily weak for improved performance with sports-related activities.

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