title: Long-Term Outcome and Factors Affecting Prognosis of Extracorporeal Shockwave Therapy for Chronic Refractory Achilles Tendinopathy.
abstract: OBJECTIVE
  To investigate the factors affecting prognosis of extracorporeal shockwave therapy (ESWT) for chronic refractory Achilles tendinopathy (AT).
  
  
  METHODS
  Thirty-six patients (48 consecutive feet) with chronic AT (>6 months) and who underwent ESWT for 'poor' or 'fair' grade in Roles-Maudsley Score (RMS) after unsuccessful conservative treatment were included in the present study. A maximum of 12 sessions of ESWT were conducted until treatment success: RMS reached 'good' or 'excellent'. Termination of ESWT for no response, or 'poor' or 'fair' grade was regarded as treatment failure. Immediate outcome, long-term outcome (telephone interview after mean 26 months), and factors affecting treatment success were analyzed.
  
  
  RESULTS
  Numeric Rating Scale was significantly decreased at immediate and long-term follow-up. Success rate was 71.1% and 90.3%, respectively. Univariate logistic regression identified that immediate treatment success was associated with retrocalcaneal enthesophyte on X-ray (odds ratio [OR], 0.06; 95% confidence interval [CI], 0.01-0.28), pretreatment abnormal ultrasonography echogenicity within Achilles tendon (OR, 18.89; 95% CI, 2.08-171.96), mean duration of 'post-treatment soreness' (OR, 0.55; 95% CI, 0.33-0.94), and duration of 'post-treatment soreness after first ESWT' (OR, 0.06; 95% CI, 0.01-0.34). The duration of 'post-treatment soreness after first ESWT' was found to be the only factor associated with long-term success (OR, 0.32; 95% CI, 0.10-0.99).
  
  
  CONCLUSIONS
  ESWT appears to be effective in achieving long-term success in chronic refractory AT. Immediate success was associated with absence of retrocalcaneal enthesophyte on X-ray, presence of pretreatment abnormal ultrasonography echogenicity, shorter mean duration of 'post-treatment soreness', and shorter duration of 'post-treatment soreness after first ESWT'. The shorter duration of 'post-treatment soreness after first ESWT' was identified as the only positive prognostic parameter in achieving long-term success.
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Joon-Youn
authors.identifier: 0000-0002-2962-527X
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyungjae
authors.identifier: 0000-0002-2765-4309
authors.initials: K
authors.lastname: Yoon
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Youbin
authors.identifier: 0000-0001-5707-3815
authors.initials: Y
authors.lastname: Yi
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Chul-Hyun
authors.identifier: 0000-0002-9897-6612
authors.initials: CH
authors.lastname: Park
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jung-Sang
authors.identifier: 0000-0001-5423-3772
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Physical Medicine and Rehabilitation, Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong, Korea.
authors.forename: Kyoung-Ho
authors.identifier: 0000-0002-9139-1638
authors.initials: KH
authors.lastname: Seo
authors.affiliation: Department of Physical and Rehabilitation Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Korea.
authors.forename: Young Sook
authors.identifier: 0000-0003-2752-7120
authors.initials: YS
authors.lastname: Park
authors.affiliation: Department of Physical and Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yong-Taek
authors.identifier: 0000-0001-6611-0999
authors.initials: YT
authors.lastname: Lee
keywords: Prognosis; Tendinopathy; Treatment outcome; Ultrasonic shockwave