Tendon structural and mechanical properties do not differ between genders in a healthy community‐dwelling elderly population

Abstract

Elderly women are reportedly at higher risk of falling than their male counterparts. Postural balance is highly associated with fall risk and is also correlated with tendon structural and mechanical properties. Gender differences in tendon properties could partly explain the discrepancy in fall risk. Thus the purpose of this study was to investigate the possible gender difference in tendon properties in the elderly. The properties of the patellar tendon of 55 elderly (men n ¼ 27, aged 72 AE 1 years, women n ¼ 28, aged 70 AE 1 years) participants were tested. Tendon stiffness (K), length (L), and cross-sectional area (CSA) were measured using B-mode ultrasonography, dynamometry, and electromyography during ramped isometric knee extensions. There were no significant differences ( p > 0.05) between men and women in tendon stiffness (elderly men 550.9 AE 29.2 vs. women 502.9 AE 44.9 Nmm À1 ) or in Young's modulus (elderly men 0.32 AE 0.02 vs. women 0.36 AE 0.04 GPa). This elderly group had similar tendon structural and mechanical properties. The comparable characteristics in genderspecific tendon properties in an elderly population exhibiting similar lifestyle characteristics to the current sample may not explain the reports in the literature regarding increased fall risk in elderly women relative to that seen in men of a similar age. Keywords: aging; gender differences; patellar tendon; stiffness; Young's modulusIn the last 30 years the proportion of the population aged 65 years or more has increased to 16% in the UK and this increase is set to continue (The Office for National Statistics, 2006). Approximately one-third of people aged over 65 fall at least once a year, and about half of these do so recurrently, leading to injury and subsequent decrease in quality of life, and in many cases death. 1 Elderly women exhibit a higher risk of falling than their male counterparts, 2,3 and most falls occur after a loss of stability in a forward direction such as tripping while walking. 2 In order to maintain balance individuals require information concerning the orientation of the body in space and the geometry of the body. In humans this information is obtained via the complex interactions of sensory systems (primarily the somatosensory, visual, and vestibular systems) and motor systems. 4 Aging results in a decline in the function of these systems and their interaction, which has been related to reduced balance ability and thus increased fall risk. [5][6][7]

Structural and mechanical properties of the human Achilles tendon: Sex and strength effects

“…Although our subject population consisted of trained cyclists, we found variation in stiffness between subjects (Fig. 3), which is again consistent with previous literature (Burgess et al, 2009; Kubo et al, 2003; Duclay et al, 2009). Despite the relative homogeneity of our subject population the predictive relation between mass and tendon stiffness had poor predictive power, r 2 = 0.01, and this increased to only r 2 =0.19 when F max was used instead of mass for the regression: it is likely that there would be an even greater uncertainty in predicting tendon stiffness across different populations.…”

“…However, the accuracy of these simulations is sensitive to the values used for tendon stiffness and resting length (Gerus and Berton, 2012). Despite considerable variability in these tendon properties between individuals (Burgess et al, 2009; Kubo et al, 2003; Duclay et al, 2009), many studies use generic values for the tendon properties.…”

Subject-Specific Tendon-Aponeurosis Definition in Hill-Type Model Predicts Higher Muscle Forces in Dynamic Tasks

“…The ratio was close to 0.5 for the GM and GL whereas the mean value was 0.23 for the SOL. This lower ratio for the soleus leads to tendon-aponeurosis characterization stiffer than the three others muscles but still less stiff than the generic condition currently used into EMG-driven model [7]. Taken together, these results suggest a clear difference in terms of mechanical properties of the SEE for the two conditions tested in the present study (i.e., generic vs. SS T-A).…”

“…Second, the generic definition is applied to models regardless of the nature of the task and the subject. Recent studies have shown a large variability in tendon mechanical properties depending on the sex [7], the type exercise [8], the age [9], and the loading rate (rate of force application to the tissue) [10], [11]. Finally, the generic definition is used to represent both the tendon and aponeurosis mechanical properties assuming their respective mechanical properties are equivalent.…”

The Association Between Fall History and Physical Performance Tests in the Community-Dwelling Elderly: A Cross-Sectional Analysis

“…Women, in particular, are more prone to falls and have a higher predisposition than men to fall-related injuries, namely, to osteoporotic fractures [3536]. Although several authors have cited sex differences in the mechanical properties of tendons to explain the discrepancies in the risks for falling [37], the reasons for a higher incidence of falls in women are not well known. One study reported that prevalence for fallers and the annual rates of falls were higher among women than men; however when controlled for each health or physical fitness variable, the Mantel-Haenszel test revealed no differences between the percentages of the men and the women who fall [38].…”