title: Eccentric training decreases paratendon capillary blood flow and preserves paratendon oxygen saturation in chronic achilles tendinopathy.
abstract: METHODS
  A controlled, randomized, prospective study,
  
  
  OBJECTIVE
  To assess the changes in paratendon microcirculation after 12 weeks of daily painful eccentric training in individuals with chronic Achilles tendinopathy.
  
  
  BACKGROUND
  Changes in tendon and paratendon microcirculation are evident in insertional and midportion Achilles tendinopathy. Whether the paratendon is involved in eccentric training response is not known.
  
  
  METHODS
  Twenty patients with chronic Achilles tendinopathy were recruited for a prospective, controlled trial using eccentric exercise. A laser Doppler system assessed capillary blood flow (flow), tissue oxygen saturation (SO2), and postcapillary venous filling pressure (rHb) at 8 paratendon locations at depths of 2 and 8 mm.
  
  
  RESULTS
  Pain in the eccentric-training group was reduced by 48% (from a mean of 4.1 +/- 2.9 to 2.1 +/- 2.2, P<.05). Deep paratendon blood flow decreased at the midportion paratendon location (P<.05). Superficial blood flow at the medial distal midportion position (by 31%, P = .008) and the lateral proximal midportion location (by 45%, P = .016) were significantly decreased postintervention, No significant change of superficial or deep paratendon oxygenation was found after intervention as compared to baseline. Deep paratendon postcapillary venous filling pressures were significantly reduced following eccentric training (P<.05).
  
  
  CONCLUSIONS
  An eccentric-training program performed daily over 12 weeks reduced the increased paratendinous capillary blood flow in Achilles tendinopathy by as much as 45% and decreased pain level based on a visual analog scale. Local paratendon oxygenation was preserved while paratendinous postcapillary venous filling pressures were reduced after 12 weeks of eccentric training, which appears to be beneficial from the perspective of microcirculation.
authors.affiliation: Plastic, Hand and Reconstructive Surgery, Hannover Medical School, Hannover, Germany. kknobi@yahoo.com
authors.forename: Karsten
authors.initials: K
authors.lastname: Knobloch
authors.forename: Robert
authors.initials: R
authors.lastname: Kraemer
authors.forename: Michael
authors.initials: M
authors.lastname: Jagodzinski
authors.forename: Johannes
authors.initials: J
authors.lastname: Zeichen
authors.forename: Rupert
authors.initials: R
authors.lastname: Meller
authors.forename: Peter M
authors.initials: PM
authors.lastname: Vogt
mesh_terms: D000125:Achilles Tendon / Q000098:blood supply* / Q000293:injuries / Q000503:physiopathology; D000328:Adult; D000704:Analysis of Variance; D002908:Chronic Disease; D005260:Female; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation; D010100:Oxygen / Q000097:blood*; D010147:Pain Measurement; D010806:Physical Education and Training; D011446:Prospective Studies; D013177:Sports / Q000502:physiology; D052256:Tendinopathy / Q000503:physiopathology* / Q000534:rehabilitation*; D016896:Treatment Outcome
chemical_list: D010100:Oxygen