Association Between Clinical and Imaging Outcomes After Therapeutic Loading Exercise in Patients Diagnosed With Achilles or Patellar Tendinopathy at Short- and Long-Term Follow-up: A Systematic Review.

OBJECTIVE: To determine the association between clinical and imaging outcomes after therapeutic loading exercise in Achilles tendinopathy (AT) and patellar tendinopathy (PT) populations at both short- and long-term follow-up. DATA SOURCES: The PUBMED and EMBASE databases were searched (up to June 2017) to identify articles that meet the inclusion criteria: (1) patients diagnosed with AT (insertional or midportion) or PT; (2) rehabilitation based on therapeutic loading exercise; and (3) assessment of clinical outcomes and tendon structure using an imaging modality. MAIN RESULTS: Two independent reviewers screened 2894 search results, identifying 21 suitable studies. According to the studies included in this review, clinical results showed significant improvements for patients with AT and PT after eccentric exercise (ECC) and heavy slow resistance (HSR) at short- and long-term follow-up. Imaging outcomes were not consistent. Moderate-to-strong evidence for patients with AT suggested an association between clinical outcomes and imaging outcomes (tendon thickness and tendon neovascularization) after ECC at long-term follow-up. For patients with PT, there was moderate evidence supporting an association between clinical outcomes (questionnaire score and pain) and imaging (tendon thickness and tendon neovascularization) after ECC at short-term follow-up. For both the AT and PT groups, there was moderate evidence for an association between clinical outcomes and tendon thickness and neovascularization after HSR exercise. Results related to the HSR exercise should be interpreted with caution because of the small number of studies. CONCLUSIONS: Based on the findings of the present review, the use of imaging outcomes as a complementary examination to the clinical assessment was confirmed. Overall, an improvement in clinical outcomes seems to be associated with a reduction in tendon thickness and tendon neovascularization. Clinicians should be aware that during the interpretation of the imaging outcomes, factors such as tendinopathy location, exercise modality performed, and a follow-up period should be considered.

The effect of load on Achilles tendon structure in novice runners.

OBJECTIVES: To observe the changes in Achilles tendon structure in novice runners, with loading prescriptions of 100% body weight compared to 20% body weight. DESIGN: Randomised crossover. METHODS: Twenty novice runners participated in two separate running bouts spaced 14days apart, one of high load at 100% body weight, and one of low load at 20% body weight. Tendon structure was measured by ultrasonographic tissue characterisation on 6 occasions; immediately prior to each run, 2 and 7days after each run. RESULTS: The interaction effect of time and condition was not found to be significant for echotypes I-IV [Wald chi-square=2.8, d.f.=2, P=0.247; Wald chi-square=2.888, d.f.=2, P=0.236; Wald chi-square=1.385, d.f.=2, P=0.5; Wald chi-square=4.19, d.f.=2, P=0.123], respectively. A significant effect of time was found for echotypes III [Wald chi-square=6.785, d.f.=2, P=0.0.034] and IV [Wald chi-square=7.491, d.f.=2, P=0.0.024]. CONCLUSIONS: The decrease in echotypes III and IV suggest that moderate loads can be applied to the Achilles tendon without compromising tendon structure. Low to moderate loads may be beneficial in the management of Achilles tendinopathy. Further studies should focus on protocols with higher loading and/or repetitive loading in athletic populations with and without Achilles tendinopathy to assess any differences in tendon structure.

External abdominal oblique muscle ultrasonographic thickness changes is not an appropriate surrogate measure of electromyographic activity during isometric trunk contractions.

BACKGROUND: The function of specific abdominal muscles can be assessed using both electromyography (EMG) and ultrasound imaging (USI) thickness measures. However, the relationship between these two measurements is not conclusive during sitting isometric trunk efforts. OBJECTIVE: This study was conducted to assess the relationship between USI thickness and EMG amplitude measures of the right external oblique (EO) muscle during isometric efforts in the sitting position. METHOD: Eighteen subjects performed ramp isometric efforts progressing from 0 to 50% of their maximal voluntary contraction (MVC) in three trunk directions on a dynamometer: (1) forward flexion; (2) right lateral flexion; and (3) left axial rotation. USI and surface EMG amplitude measures of the EO muscle were recorded concomitantly and both normalized against rest values and maximal EMG, respectively. RESULTS: EO muscle was significantly more activated (p < 0.001) during forward flexion (42% on average) and axial rotation (35%) than during lateral flexion (24%). Non-significant (r=0.01; P=0.979) to highly significant (r=0.98; P < 0.0001) and negative and positive Pearson correlations were observed between EMG and EO thickness measures for both flexion and rotation directions. CONCLUSION: The negative correlations between EMG and USI measures as well as the great variability of these correlations across individuals suggest that USI is not a valid measures of EO muscle activity. USI thickness measures should be interpreted with great caution in research and clinical settings.