title: The Tendon Structure Returns to Asymptomatic Values in Nonoperatively Treated Achilles Tendinopathy but Is Not Associated With Symptoms: A Prospective Study.
abstract: BACKGROUND
  Tendinopathy is characterized by alterations in the tendon structure, but there are conflicting results on the potential of tendon structure normalization and no large studies on the quantified, ultrasonographic tendon structure and its association with symptoms.
  
  
  OBJECTIVE
  To determine whether the tendon structure returns to values of asymptomatic individuals after treatment with 2 substances injected within the tendon, to assess the association between the tendon structure and symptoms, and to assess the prognostic value of the baseline tendon structure on treatment response.
  
  
  METHODS
  Cohort study; Level of evidence, 2.
  
  
  METHODS
  This study was part of a randomized trial on chronic midportion Achilles tendinopathy using eccentric exercises with either a platelet-rich plasma or saline injection. Symptoms were recorded using the Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire. The tendon structure was quantified with ultrasound tissue characterization (UTC); echo types I + II (as a percentage of total tendon types I-IV) are structure related. Follow-up was at 6, 12, 24, and 52 weeks. A control group of asymptomatic subjects (similar age) was selected to compare the tendon structure. Patient symptoms were correlated with the tendon structure using a linear model.
  
  
  RESULTS
  Fifty-four patients were included in the symptomatic group. The mean (± SD) echo types I + II in the symptomatic group increased significantly from 74.6% ± 10.8% at baseline to 85.6% ± 6.0% at 24-week follow-up. The result for echo types I + II at 24 weeks was not significantly different (P = .198) from that of the asymptomatic control group (87.5% ± 6.0%). In 54 repeated measurements at 5 time points, the adjusted percentage of echo types I + II was not associated with the VISA-A score (main effect: β = .12; 95% CI, -0.12 to 0.35; P = .338). The adjusted baseline echo types I + II were not associated with a change in the VISA-A score from baseline to 52 weeks (β = -.15; 95% CI, -0.67 to 0.36; P = .555).
  
  
  CONCLUSIONS
  In symptomatic, tendinopathic Achilles tendons, the ultrasonographic tendon structure improved during nonoperative treatment and normalized after 24 weeks to values of matched asymptomatic controls. There was no association between the tendon structure and symptoms. The percentage of echo types I + II before treatment was not associated with change in symptoms over time. This study demonstrates that restoration of the tendon structure is not required for an improvement of symptoms.
authors.affiliation: Department of Orthopaedics, Erasmus Medical Centre, Rotterdam, the Netherlands Department of Sports Medicine, The Hague Medical Center Antoniushove, Leidschendam, the Netherlands s.dejonge@erasmusmc.nl.
authors.forename: Suzan
authors.initials: S
authors.lastname: de Jonge
authors.affiliation: The Sports Physician Group, Department of Sports Medicine, St Lucan Andreas Hospital, Amsterdam, the Netherlands Department of Sports Medicine, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar Academic Center for Evidence Based Sports Medicine, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Johannes L
authors.initials: JL
authors.lastname: Tol
authors.affiliation: Department of Sports Medicine, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Adam
authors.initials: A
authors.lastname: Weir
authors.affiliation: Department of Orthopaedics, Erasmus Medical Centre, Rotterdam, the Netherlands.
authors.forename: Jan H
authors.initials: JH
authors.lastname: Waarsing
authors.affiliation: Department of Orthopaedics, Erasmus Medical Centre, Rotterdam, the Netherlands.
authors.forename: Jan A N
authors.initials: JA
authors.lastname: Verhaar
authors.affiliation: Department of Orthopaedics, Erasmus Medical Centre, Rotterdam, the Netherlands.
authors.forename: Robert-Jan
authors.initials: RJ
authors.lastname: de Vos
mesh_terms: D000125:Achilles Tendon / Q000473:pathology* / Q000648:ultrastructure; D000328:Adult; D015331:Cohort Studies; D015444:Exercise; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053657:Platelet-Rich Plasma; D011446:Prospective Studies; D052256:Tendinopathy / Q000628:therapy*; D016896:Treatment Outcome
keywords: Achilles tendon; VISA-A; eccentric exercise; injection therapy; tendinopathy; ultrasound tissue characterization